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P Raivio

Publications and source records attributed to P Raivio.

9 recordsLinked to original sources
PubMed2006

Thrombin generation during reperfusion after coronary artery bypass surgery associates with postoperative myocardial damage.

BACKGROUND: Cardiopulmonary bypass and coronary artery bypass grafting (CABG) result in significant thrombin generation and activation of fibrinolysis. Thrombin contributes to myocardial ischemia-reperfusion injury in animal studies, but the role of thrombin in myocardial damage after CABG is unknown. OBJECTIVES: We measured thrombin generation and fibrin turnover during reperfusion after CABG to evaluate their associations with postoperative hemodynamic changes and myocardial damage. METHODS: One hundred patients undergoing primary, elective, on-pump CABG were prospectively enrolled. Plasma prothrombin fragment F(1+2) and D-dimer were measured preoperatively and at seven time points thereafter. Mass of the Mb fraction of creatine kinase (Ck-Mbm) and troponin T (TnT) were measured on the first postoperative day. RESULTS: Reperfusion induced an escalation of thrombin generation and fibrin turnover despite full heparinization. F(1+2) during early reperfusion associated with postoperative pulmonary vascular resistance index. F(1+2) at 6 h after protamine administration correlated with Ck-Mbm (r = 0.40, P < 0.001) and TnT (r = 0.44, P < 0.001) at 18 h postoperatively. Patients with evidence of myocardial damage (highest quintiles of plasma Ck-Mbm and TnT) had significantly higher F(1+2) during reperfusion than others (P < 0.002). Logistic regression models identified F(1+2) during reperfusion to independently associate with postoperative myocardial damage (odds ratios 2.5-4.4, 95% confidence intervals 1.04-15.7). CONCLUSIONS: Reperfusion caused a burst in thrombin generation and fibrin turnover despite generous heparinization. Thrombin generation during reperfusion after CABG associated with pulmonary vascular resistance and postoperative myocardial damage.

Adult↗
PubMed2004

The role of biofeedback therapy in functional proctologic disorders.

BACKGROUND AND AIMS: The question which patients with functional proctologic disorders truly benefit from the biofeedback has not been equivocally resolved. The aim of this study was to assess our results of biofeedback therapy in patients with anal incontinence or constipation. MATERIAL AND METHODS: Fifty-two consecutive patients who were treated with biofeedback therapy between January 1998 and March 2002 were studied. Data was collected from our proctologic database. RESULTS: Of the twenty-two patients with anal incontinence who underwent biofeedback therapy during the study period, twenty patients had incontinence affecting quality of life. Twelve patients (60 percent) benefited from biofeedback as judged by improvement of incontinence symptoms affecting quality of life; all four patients with partial sphincter defects, three out of four patients after secondary repair, three out of five patients with persistent incontinence after rectal prolapse surgery and two out of seven patients having idiopathic incontinence. Of the thirty patients who underwent biofeedback therapy for constipation, twenty-five had intractable symptoms of constipation. Constipation resolved in sixteen patients (64 percent); in thirteen out of nineteen (68 percent) of those with pelvic floor dysfunction (PFD) and in three out of six (50 percent) having combined PFD and slow transit constipation. In patients with PFD constipation was resolved in ten out of thirteen patients (77 percent) with anismus but in only three out of six (50 percent) having other causes. CONCLUSIONS: Biofeedback therapy improves incontinence after sphincter repairs and in patients with partial external sphincter defects, but does not improve idiopathic incontinence. Biofeedback is also effective in patients with constipation, especially when anismus is the only cause for symptoms of constipation and difficult evacuation.

Adult↗
PubMed2001

Effects of extrinsic denervation with or without ischemia-reperfusion injury on constitutional mucosal characteristics in porcine jejunoileum.

We investigated the effects of jejunoileal denervation with or without ischemia-reperfusion on mucosal characteristics and small intestinal structure. Growing pigs underwent sham laparotomy, jejunal transection, or extrinsic jejunoileal denervation with or without in situ ischemia-reperfusion. Small intestinal morphology, crypt cell proliferation, enterocyte ultrastructure, and disaccharidase activities were analyzed from jejunum and ileum after eight weeks. Immunohistological analysis of the ileum showed no staining of catecholaminergic neurons after extrinsic denervation. Neural isolation of the jejunoileum with or without ischemia-reperfusion injury reduced weight gain and villous enterocyte density in the ileum, abolished the proximodistal gradient of sucrase activity, and increased mucosal thickness, villus height, and villus surface area in the ileum. However, gross jejunoileal morphology, crypt cell proliferation, and enterocyte ultrastructure remained unchanged. In conclusion, jejunoileal denervation in growing pigs selectively modulates constitutional mucosal characteristics in the ileum, presumably due to altered enterocyte turnover, without a decrease in small intestinal absorptive surface area. These changes are independent of short ischemia and subsequent reperfusion.

Animals↗
PubMed1997

Adaptive lipid metabolism after ileal autotransplantation in pigs with proximal gut resection.

BACKGROUND: Transplantation of the small intestine impairs intestinal absorptive function, but the adaptive response of a segmental graft is unknown. The aim of this study was to investigate the effects of ileal autotransplantation on the adaptive absorption and metabolism of lipids in pigs that had undergone proximal gut resection. METHODS: Serum lipids, plasma vitamins A and E, absorption and excretion of cholesterol, bile acids and fat, plasma cholesterol precursor and plant sterol proportions to cholesterol (respective markers of cholesterol synthesis and absorption), enteric structure, and transit were determined 4, 8, and 14 weeks after 75% proximal resection with (n = 15) or without (n = 15) autotransplantation of the remaining ileum. RESULTS: As compared with pigs that underwent proximal gut resection, the additional autotransplantation reduced the adaptive increase in total serum and high-density lipoprotein cholesterol, plasma plant sterol proportions and vitamin E concentrations, cholesterol and fat absorption efficiency, and villus height (p < 0.05 for all) during the 14 postoperative weeks and resulted in increases of up to 4.6, 2.7, 1.3, and 2.1 times the plasma cholesterol precursors (p < 0.005), fecal excretion of bile acids (p < 0.0005), neutral steroids (p < 0.005), and net elimination of cholesterol (p < 0.0005), respectively. Cholesterol and fat absorption and plasma plant sterols were significantly enhanced between 8 and 14 weeks after autotransplantation (p < 0.05, p < 0.005, and p < 0.05, respectively), whereas fecal elimination of cholesterol remained increased until the end of the follow-up. CONCLUSIONS: Autotransplantation of the ileum in pigs that have undergone proximal small bowel resection disturbs the adaptive absorption of cholesterol, bile acids, fat, and fat-soluble vitamins, resulting, through increased fecal elimination of cholesterol, in decreased serum cholesterol despite a marked compensatory increase in cholesterol synthesis.

Animals↗
PubMed1996

Biofeedback therapy in rectal prolapse patients.

PURPOSE: The aim of the study was to evaluate the effect of perioperative biofeedback training on postoperative continence in patients with rectal prolapse. METHODS: Thirty-six consecutive patients were operated on between 1987 and 1993. Twenty-nine could be traced for reexamination. Four were excluded because of a recurring prolapse. Anal manometry, assessment of rectoanal sensation, and surface electromyography were performed during the reexamination. From 1987 to 1991, no perioperative biofeedback training was given (Group 1, n = 14). Since the beginning of 1992, incontinent patients were given biofeedback training (Group 2, n = 11). RESULTS: Continence scores improved in both study groups. Both study groups had equally low resting pressures compared with Group 3 (controls) (30.6 +/- 14.9 vs. 53.0 +/- 11.9 mmHg; P < 0.001). Anal resting pressure correlated with postoperative continence score, whereas contractile pressures did not (r = -0.5,P < 0.05, and r = -0.3, p = not significant, respectively). CONCLUSION: Biofeedback therapy can improve the function of external sphincter; however, the most important reason for postoperative incontinence in rectal prolapse patients is low resting pressure that cannot be corrected by biofeedback therapy.

Aged↗
PubMed1996

Adaptation of cholesterol absorption after proximal resection of porcine small intestine.

Cholesterol absorption occurs primarily in the upper small intestine. Our aim was to assess absorption of cholesterol during ileal adaptation after proximal small intestinal resection. In vivo absorption and elimination of cholesterol, plasma cholesterol, cholesterol precursors, and plant sterols were related to intestinal morphology and transit 4 (n = 5), 8 (n = 5), and 14 (n = 5) weeks after a 75% proximal resection of porcine small intestine, and compared to preoperative (n = 5) and transected (n = 5) control animals. Fractional cholesterol absorption, the daily amount of cholesterol absorbed, plasma cholesterol, and plant sterol to cholesterol proportions were significantly (P < 0.05 or less) decreased, whereas fecal loss of cholesterol as neutral steroids, less so as bile acids, plasma cholesterol precursor proportions, and ileal mass and villus height were significantly increased (P < 0.05 or less) after 8 weeks of the resection. Cholesterol absorption efficiency, decreased by the resection, was gradually increased from 5.4 +/- 2.2 to 26.9 +/- 3.9% during the 14 postoperative weeks (P < 0.0001) simultaneously with a 46% increase in villus height compared with transection (P < 0.0001), but absorption remained still below control levels (80.4 +/- 2.5%, P < 0.0001). In resected and control animals, villus height correlated positively with cholesterol absorption efficiency (r = 0.85, P < 0.0001; r = 0.76, P = 0.01) and plasma plant sterol proportions (r = 0.94-0.95, P < 0.0001; r = 0.78-0.85, P < 0.008), respectively. In conclusion, after massive proximal small bowel resection, adaptation of intestinal cholesterol absorption efficiency occurs in the distal ileum closely parlleling villus hypertrophy.

Adaptation, Physiological↗
PubMed1992

A new low-frequency platelet alloantigen, Vaa, on glycoprotein IIbIIIa associated with neonatal alloimmune thrombocytopenia.

We describe platelet alloimmunization which caused severe thrombocytopenia in a neonate and could only be detected by testing the father's platelets. The platelet-specific antibodies were identified by a monoclonal antibody-immobilized platelet protein assay (MAIPA) using monoclonal antibodies against glycoprotein (GP) IIbIIIa complex (AP2 and 2G12). The previously described alloantigen systems on the GPIIbIIIa complex (HPA 1, HPA 3 or HPA 4) were not responsible for the reaction. In addition the newly described private platelet antigen Sra was not identical to the antigen. The antigen is therefore different from all known platelet alloantigens and was designated Vaa. The antigen was present on the platelets of the affected child. Family studies showed that the platelet antigen was transmitted as an autosomal dominant trait in three generations. No Va (a+) individuals were found in a population study of 250 blood donors, which indicates that the antigen is of low frequency in the Finnish population. The Va antigen was not detectable by immunoblot analysis, which suggests that the epitope may not be a linear peptide structure. The antigen was also destroyed by solubilization of platelets. Thrombin activation of platelets, known to increase the expression of GPIIbIIIa on platelets, did not increase the number of binding sites for anti-Vaa antibodies to the extent observed with anti-HPA 1a binding.

Adult↗