Biomedical subjects

Pekka Laippala

Publications and source records attributed to Pekka Laippala.

43 records · Page 3Linked to original sources

PubMed2002

Effect of blood loss on vascular responsiveness in pedicled groin flaps in a rat model.

Using the clamping method (closing and opening the flap feeding artery) and continuous laser Doppler flowmetry, the effects of blood withdrawals on flap blood flow and on active and passive mechanisms regulating it were investigated in 12 Sprague-Dawley rats. Measurements were made during stable normovolemic conditions, during hypovolemia (after 3 ml/kg and after 6 ml/kg blood withdrawal), and after retransfusion of the shed blood. The continuous blood flow responses during and after the clamping procedure were analyzed. After clamp release, the increase in blood flow, duration of overshoot, and peak flow of overshoot were significantly greater (the level of significance was set equal to 0.05) in the registrations performed after blood withdrawals than before them. The post-ischemic response curves indicating significantly increased flap hyperemia during reperfusion in the registrations after blood withdrawals may be associated with decreased vascular resistance in the flap. Thus, the authors conclude that a short-term decrease in blood pressure caused by blood loss may prepare the flap microcirculation for tolerating more ischemia.

Animals↗

PubMed2002

Comparison of nitric oxide donors in lowering intraocular pressure in rabbits: role of cyclic GMP.

L-arginine-nitric oxide (NO) pathway participates in the physiology and in many pathological processes in the eye, such as glaucoma. The aim of the present study was to compare the ocular hypotensive effect of different NO-donors, and to get more information on the role of cyclic guanosine 3',5'-monophosphate (cGMP) in this process. The test compounds were administered topically or intravitreally in the eye of a normotensive rabbit. Intraocular pressure (IOP) was measured with a pneumatonometer after topical anesthesia. The metabolites of NO (nitrite, nitrate, NOx) and cGMP were assayed from the aqueous humor and plasma. NO-synthase (NOS) protein expression was assayed in the ciliary body by Western blotting. The maximal lowering of IOP was achieved as follows: atriopeptin III (concentration 78 (microM, decrease in IOP 50%), atriopeptin II (84 (microM 37%). 8-Br-cGMP (90 mM, 37%), zaprinast + 8-Br-cGMP (1 mM + 90 mM, 34%), L-arginine (1 mM, 29%), SNP (40 mM, 28%), nitrosocaptopril (100 mM, 28%), S-nitrosothiol (SNOG) (10 mM, 27%), YC-1 (10 (microM, 25%), zaprinast + SNP (1 mM + 40 mM, 22%), spermine NONOate (100 mM, 20%) [corrected]. The decrease in IOP lasted for 2-5 hr, except with atriopeptin II and III, when IOP values were first normalized in 6 hr and 2 days, respectively. In conclusion, the results of the present study indicate that by increasing the activity of L-arginine/NO/cGMP-pathway it is possible to lower IOP in rabbits equally to the currently used antiglaucomatous drugs.

Animals↗

PubMed2002

Preservation of urine for flow cytometric and visual microscopic testing.

BACKGROUND: Preservatives that could prevent destruction of cells, casts, and bacteria in urine are of great practical importance because they allow centralization and improvement of accuracy of urine particle counting. We compared two in-house mixtures and one commercial solution, as well as refrigeration, for their ability to preserve urine for both automated analysis (flow cytometry) and visual microscopy. METHODS: Urine specimens were preserved by refrigeration at 4 degrees C without preservatives (procedure 1); in a lyophilized solution intended to preserve specimens for bacterial culture (Urine C&S tubes; BD Preanalytical Solutions; procedure 2); in 10 mL/L formalin-0.15 mol/L NaCl (procedure 3); in 80 mL/L ethanol-20 g/L polyethylene glycol (procedure 4); and by storage at 20 degrees C without preservatives (procedure 5). Test strip measurements were used to select specimens positive for leukocyte esterase, hemoglobin, albumin, or nitrite. For 106 consecutive strip-positive specimens, urinalysis was performed by UF-100 (Sysmex) and by phase-contrast microscopy after Sternheimer supravital staining. Automated analysis was performed at arrival in the morning, on the same day in the afternoon, and after 1 and 3 days. Visual microscopy was performed at arrival and 3 days later. RESULTS: Urine bacterial counts were well preserved with procedures 1-3, with a false-positive rate of 0.0-3.4% at day 3 vs 28% without preservation (procedure 5). Erythrocytes were poorly preserved for 3 days (kappa coefficients, 0.24-0.61); after 1 day, fair preservation was seen with procedure 2 (kappa = 0.78), compared with less favorable preservation with procedure 1 (kappa = 0.61) or procedure 5 (kappa = 0.66). Leukocytes were well preserved by all five procedures in the acidic adult urines investigated. Counts of casts and large epithelial cells were artifactually increased by procedure 3. Procedure 2 performed at least as well as refrigeration for specimens analyzed with visual microscopy. CONCLUSIONS: Urine specimens from adults can be stabilized at room temperature for both automated particle analysis and visual microscopy.

Adult↗

PubMed1999

Peripherally administered sufentanil inhibits pain perception after postpartum tubal ligation.

The clinical effectiveness of locally administered opioids is still under discussion; in particular, the potency of morphine in settings other than intra-articular arthroscopy has been questioned. We developed another pain model, postpartum resection of the fallopian tubes for sterilisation, in which each patient serves as her own control when one side is infiltrated with the active drug (in this study sufentanil 5 mg) and the contralateral side with normal saline. In the control group both sides are infiltrated with plain saline. After 30 min from the end of anaesthesia onwards, 26 out of 30 patients observed significant pain relief on the side of the sufentanil infiltration, which in 11 patients lasted until the end of the observation period 24 h postoperatively; no difference was observed in the control group. In our pain model with a high assay sensitivity, the infiltration of one side with the lipophilic test drug, sufentanil, caused local analgesia in primarily non-inflamed tissue. The use of each patient as her own control excluded inter-subject bias.

Adult↗

PubMedDate not supplied

Apolipoprotein E gene polymorphism, hypercholesterolemia and glomerular filtration rate in type 2 diabetic subjects: a 9-year follow-up study.

OBJECTIVE: To study the association between apolipoprotein E (apoE) genotype and the rate of decline in glomerular filtration rate (GFR) in type 2 diabetic patients in a 9-year prospective study. METHODS: GFR was determined in 84 type 2 diabetic patients by plasma clearance of (51)Cr-EDTA at baseline and after 9 years of follow-up. ApoE genotypes were determined by polymerase chain reaction and restriction enzyme HHAI digestion and designated as epsilon4 allele group (apoE4/2, 4/3 and 4/4 genotypes; n = 20) and non-epsilon4 allele group (apoE3/3 and E3/2 genotypes; n = 64). We focused our analysis on those patients who were more likely to progress to diabetic renal disease, i.e. whose GFR fell more than expected in the normal course of ageing [1 ml x min(-1) x (1.73 m(2))(-1) per year]. RESULTS: In the whole population, the decline in the GFR did not differ statistically significantly between the apoE genotype groups [p = 0.65 with analysis of variance for repeated variables (RANOVA) for interaction between apoE genotype group and time point]. However, among patients whose GFR changed more than 9 ml x min(-1) x (1.73 m(2))(-1), GFR showed a statistically significantly greater decline in the epsilon4 allele group (n = 11) than in the non-epsilon4 allele group (n = 43) [from 116 +/- 36 to 80 +/- 29 ml x min(-1) x (1.73 m(2))(-1) vs. from 119 +/- 20 to 96 +/- 18 ml x min(-1) x (1.73 m(2))(-1); p = 0.005 with RANOVA]. CONCLUSION: ApoE allele epsilon4 may speed up the rate of decline of the GFR in patients with progressive diabetic renal disease.

Adult↗

PubMedDate not supplied

Oxidized LDL autoantibodies are related to apolipoprotein E phenotype, independently of postprandial change in plasma triglycerides and LDL size, among patients with angiographically verified coronary artery disease and healthy controls.

OBJECTIVE: Oxidized low-density lipoprotein (LDL) autoantibodies (oxLDLab), apolipoprotein E (apoE) phenotype, postprandial triglyceride changes and LDL size are suggested to be risk factors for coronary artery disease (CAD). Our aim was to study the interaction between these new risk factors among patients with CAD and healthy controls. METHODS: oxLDLab from 31 men with angiographically verified CAD and 31 healthy men were analyzed by enzyme-linked immunosorbent assay. Isoelectric focusing and immunoblotting were used for apoE phenotyping. Triglyceride level was measured after 12 h of fasting and 3, 5 and 7 h after a high-fat meal. Nondenaturing gradient gel electrophoresis was used to separate LDL particles according to size. RESULTS: oxLD- Lab levels increased according to apoE phenotype in the following order: E2 < E3 < E4 (p = 0.004, ANOVA). The postprandial response of triglycerides, the size of LDL particles and the concentration of LDL and high-density lipoprotein (HDL) cholesterol did not differ between apoE phenotypes, and the use of these variables as covariates did not change the statistically significant difference in oxLDLab levels between apoE phenotypes (p = 0.01, ANCOVA). oxLDLab levels did not differ between the patient and control groups. CONCLUSION: We found an association between apoE allele epsilon2 and decreased levels of oxLDLab, which was independent of the postprandial response of triglycerides, the size of LDL particles and plasma LDL and HDL cholesterol levels. The mechanism by which apoE affects oxidation of LDL remains unknown.

Adult↗

PubMedDate not supplied

Gluten-free diet and quality of life in patients with screen-detected celiac disease.

CONTEXT: Since the advent of serologic testing for celiac disease, most persons who receive a diagnosis of celiac disease have few or no symptoms. Although pathologic changes of celiac disease resolve on a gluten-free diet, how a gluten-free diet affects the quality of life for patients with screen-detected celiac disease is unclear. OBJECTIVE: To evaluate the effect of a gluten-free diet on the quality of life of patients with screen-detected celiac disease. DESIGN: Prospective study of patients before and 1 year after initiating a gluten-free diet. PARTICIPANTS: 19 patients with screen-detected celiac disease (found by serologically testing first-degree relatives of celiac patients) and 21 consecutive patients with symptom-detected disease. In all cases, celiac diagnosis was confirmed by finding villous atrophy and crypt hyperplasia on small-bowel biopsy. INTERVENTION: Gluten-free diet (explained during a single physician visit). MAIN OUTCOME MEASURES: Gastrointestinal Symptoms Rating Scale (GSRS), in which scores range from 0 to 6 (higher scores represent worse symptoms); and quality of life measured with the Psychological General Well-Being Questionnaire (PGWB). Scores range from 22 to 132 (higher scores mean greater well-being). RESULTS: At baseline, patients with symptom-detected celiac disease had poorer quality of life and more gastrointestinal symptoms than those with screen-detected celiac disease. Reported compliance with the gluten-free diet was good. All mucosal lesions of the small bowel had resolved at the follow-up biopsy. After 1 year of following the diet, quality of life for patients with screen-detected disease significantly improved (mean PGWB score increased from 108 to 114; P <0.01). A similar increase was noted in patients with symptom-detected disease (mean PGWB score increased from 92 to 103; P <0.01). Gastrointestinal symptoms also improved in patients with screen-detected disease and in patients with symptom-detected disease (mean GSRS scores decreased from 1.8 to 1.4 and from 2.6 to 1.9, respectively; P <0.01 for both comparisons). CONCLUSIONS: Gluten-free diet was associated with improved quality of life for patients with symptom-detected celiac disease and patients with screen-detected celiac disease. Concerns about the burden of a gluten-free diet, at least over the short term, may be unfounded.

Adult↗