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Dive into the research topics where Pauli Virtanen is active.

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Featured researches published by Pauli Virtanen.


Cells Tissues Organs | 1988

Regeneration of D-Galactosamine-Traumatized Rat Liver with Natural Protoberberine Alkaloids from Enantia chlorantha

Pauli Virtanen; Veijo Lassila; Thomas Njimi; Denis Ekotto Mengata

Experimental liver injury was provoked in test rats with intraperitoneal injections of D-galactosamine. Traumatized rats received further intraperitoneal injections of Hepasor, a protoberberine alkaloid mixture from Enantia chlorantha (Annonaceae). Biochemical assays from blood plasma, serum alanine transferase, serum alkaline phosphatase, serum creatinine, serum hydroxyproline and serum calcium were done and liver and kidney samples for histological processing were taken. The biochemical results obtained indicate a marked influence by Hepasor on the serum alanine transferase activities and serum hydroxyproline values in female rats, but more accidental ones in male rats. A reduction in serum alkaline phosphatase activity and the serum creatinine values was also found, being also dependent on sex. The histological findings in the liver sections of female rats show that 1 week Hepasor therapy greatly furthers the healing process in a D-galactosamine-pretraumatized liver, eliminating megalocytosis, contraction of chromatines and other disorders in the cell architecture. The inhibitory effect of Hepasor on proceeded traumatization caused by D-galactosamine was nearly complete.


Cells Tissues Organs | 1988

Natural Protoberberine Alkaloids from Enantía Chlorantha, Palmatine, Columbamine and Jatrorrhizine for Thioacetamidc-Traumatized Rat Liver

Pauli Virtanen; Veijo Lassila; Thomas Njimi; Denis Ekotto Mengata

Experimental liver injury was provoked experimentally in rats with intraperitoneal injections of thioacetamide. Traumatized rats received further intraperitoneal injections of Hepasor, a protoberberine alkaloid extract from Enantia chlorantha (Annonaceae) containing palmatine, columbamine and jatrorrhizine. The development of body weight was kept under continuous control. Biochemical assays of blood plasma, serum alanine transferase (S-ALT), serum alkaline phosphatase (S-AP), serum creatinine S-CREAT, serum hydroxyproline (S-OH-PROL) and serum calcium (S-Ca) were done and liver samples for histological processing were taken. The biochemical results obtained indicate Hepasor exerted a marked influence on the S-ALT activities and S-OH-PROL values in female rats, but more incidental one in male rats. Some reduction in S-AP activity and S-CREAT values, which was also dependent on sex, was also found. The histological findings in the liver sections of female rats show that Hepasor improves the blood flow and mitotic activity in thioacetamide-traumatized livers.


Pathobiology | 1993

Protoberberine Alkaloids from Enantia chlorantha Therapy of Allyl-Alcohol-and D-Galactosamine-Traumatized Rats

Pauli Virtanen; Veijo P. Lassila; Karl-Ove Söderström

The short-term effect of the hepatotoxins allyl alcohol (AA) and D-galactosamine (GalN) was investigated in adult female rats. In addition, the curative effect of Hepasor, protoberberine extract from Enantia chlorantha was examined 3 days following traumatization. There was a significant increase in serum alanine transferase (ALT) and serum alkaline phosphatase (APHOS) values induced by AA traumatization, which were lowered following Hepasor treatment. GalN traumatization also significantly increased ALT values, APHOS values to a lesser extent, and produced a decrease in serum hydroxyproline (OH-PRO) values. Hepasor treatment prevented these changes. Liver biopsies of AA-traumatized rats revealed marked necrotic areas and increased numbers of binuclear cells. When AA traumatization was combined with Hepasor treatment, fewer morphological changes in the liver were observed. GalN also provoked a 3-fold increase in binuclear cells, about a 10-fold increase in the number of lymphocytes and an increase in the neutrophils in the liver. Notable changes in Kupffer cells and degenerating hepatocytes were also observed. Both GalN traumatization and Hepasor treatment on pretraumatized rats nearly abolished these changes. Hepasor treatment appears to prevent chemically induced traumatization and also to promote the healing process in the hepatic injury models selected.


Cells Tissues Organs | 1980

Staining properties of alizarin red S for growing bone in vitro

Pauli Virtanen; Kauko Isotupa

The pH-metric titration curve of alizarin red S (ARS) showed that ARS ionizes in three stages: firstly the -SO3Na group, secondly the beta-hydroxyl group, and finally on the alkaline side the alpha-hydroxyl group. The titration of ARS solution with calcium ions indicates that complex and chelate formation between ARS and calcium are distinct. The in vitro staining experiments were carried out at different pH levels. Completely ionized ARS had the best affinity for growing bone surfaces. The next most effective staining occurred just prior to neutralization. The least effective staining by ARS was found after the neutralization point had been reached. The presence of calcium made the dye solution inactive for staining the growing bone in vitro.


Cells Tissues Organs | 1989

Effect of Splenectomy on Hepasor Treatment in Allyl-Alcohol-Traumatized Rat Liver

Pauli Virtanen; Veijo Lassila; Thomas Njimi; Denis Ekotto Mengata

Experimental liver injury was provoked in test rats with and without spleen intraperitoneally with allyl alcohol injections. The rats without spleen were used for tests 2 months after the splenectomy. Traumatized rats received further intraperitoneal injections of Hepasor, a protoberberine alkaloid mixture from Enantia chlorantha (Annonaceae). Biochemical assays from blood plasma, serum alanine transferase, serum alkaline phosphatase, serum creatinine, serum hydroxyproline and serum calcium were done and the total amount of blood obtained by decapitation was measured. Liver and kidney samples for histological processing were taken. The biochemical results obtained show significant changes in serum hydroxyproline which increases cumulatively due to traumatization, Hepasor treatment and splenectomy. In case of spenectomy, the absolute volume of circulating blood enhanced under Hepasor treatment. The histological findings in the liver sections show that a 2-week Hepasor therapy of the 2-week pretraumatized rats greatly furthers the healing process during prolonged traumatization. The preventive effect of Hepasor was seen as a diminished occurrence of Kupffer cells, improved cell architecture and promoted mitotic activity. The sedative effect of Hepasor was pivotally evaluated, when massive intra- and extracellular damages were provoked with allyl alcohol in splenectomized rats. This indicate the high regeneration potency of Hepasor on experimentally provoked liver dysplasia.


Cells Tissues Organs | 1984

Influence of Experimental Liver Injury on Rat Blood and Alveolar Bone under Stress

Veijo Lassila; Pauli Virtanen

Experimental liver injury was induced to test rats with a daily injection of thioacetamide (ThAA). The doses used for intraperitoneal administrations were 50 mg/kg body weight. The loss of body weight in the 3-week test period was 15%. In the liver there was seen progressive changes which displayed cell necrosis and regeneration. The influence of ThAA on rat blood and serum was checked using standard biochemical assays consisting of the percentage of blood obtainable and the serum/blood ratio and analysis of serum alanine transferase, serum alkaline phosphatase, serum creatinine, and hydroxyproline in the acute, subacute, chronic, and necrotic stage of liver injury. With ThAA injections, the stimulated rate of glycosaminoglycan synthesis had its association to the serum calcium content. It decreased continuously as function of traumatization time. In the 3-week test period, histological findings show in the alveolar bone, around the teeth, when under occlusal stress and ThAA traumatization, the distinct decrease in osteoblastic activity and less osteoids indicating thus the decreased formation of new bone. Conspicuous osteoclastic resorption was also seen in the same area.


Journal of Chromatography B: Biomedical Sciences and Applications | 1980

The effect of pH and ionic strength on the electrophoretic separation of acidic glycosaminoglycans

Pauli Virtanen; Keijo Paunio

Abstract Using the electrophoretical methods applied to this study it is possible to determinate the dissociation constants (p K ) of acid glycosaminoglycans containing a carboxylic group. The p K -values of the six acid glycosaminoglycans separated from animal connective tissues determined in this work were: hyaluronic acid (HA), p K = 3.0; chondroitin sulfate A (CS-A), p K = 2.8; chondroitin sulfate C (CS-C), p K = 3.3; dermatan sulfate (CS-B), p K = 3.3; heparatin sulfate (HeS), p K = 3.1 and heparin (HeP), p K = 2.4 and were measured at a constant ionic strength of I = 0.164 (NaCl) and at 10 ± 2°C. Variation of ionic strength showed that physiological conditions seem to be most suitable for the electrophoretic separation of the glycosaminoglycans studied. A decrease of ionic strength causes increasing mobility but less accurate spots. In the case of increasing ionic strength the results are vice versa. The second spot for HA very often appeared when pH values higher than 2 were used for electrophoresis. The spot had the same form as the original, high intensity, but an undecided migration in the pH range near the p K value of HA (3.0).


Cells Tissues Organs | 1980

Effect of oxidizing agents on alizarin red S and its staining properties in vitro

Pauli Virtanen; Kauko Isotupa

Different oxidants regulate the staining ability, the hue, and the staining target in bone, cartilage and connective tissue in vitro in connection with alizarin red S (ARS). The use of oxidants should


Cells Tissues Organs | 1986

Alizarin red S-stained bone and cartilage in calcium deficiency provoked by experimental liver injury in rats

Pauli Virtanen; Veijo Lassila

Experimental liver injury with different stages was provoked in rats with daily injected doses of thioacetamide (ThAA). The dose recommended for both male and female rats was 50 mg/kg body weight. The liver damages caused were acute, subacute, cirrhotic and necrotic, with a traumatization period of 2, 7, 14 and 21 days. The loss of body weight under traumatization, indicating osteopenia, was in the case of female rats during the first experimental week markedly accelerated, and in the two subsequent weeks apparently inhibited when compared to male rats. The loss of body weight of male rats revealed a progressive fall. Vital staining was made giving intraperitoneally 200 mg/kg body weight of alizarin red S (ARS). The staining intensity was improved in the acute stage for both calvaria and tibia and in the necrotic stage for tibia only. It was impaired in the subacute stage for calvaria and tibia and in the necrotic stage for calvaria only. Prolonged traumatization with ThAA causes pathological defects in the liver and kidneys. Furthermore, the epiphyseal cartilage of necrotic-stage rats was bright red without any ARS staining.


Cells Tissues Organs | 1986

Influence of Thioacetamide-Provoked Liver Injury on Female Rat Blood and Alveolar Bone under Stress

Pauli Virtanen; Veijo Lassila

Experimental liver injury with different stages was induced to adult female test rats with daily injection of thioacetamide (ThAA). The doses administered intraperitoneally were 50 mg/kg body weight. In the liver sections progressive changes of damage, regeneration and fat substitution were noticed. Kidney sections revealed enhanced glomerular atrophy, particularly in the cortical tubules, provoked in the 3-week traumatization period. The influence of ThAA on female rat blood was assayed using standard biochemical methods. The analyses done were: the percentage of blood obtainable and the serum/blood ratio; the serum alanine transferase; serum alkaline phosphatase; serum creatinine; serum hydroxyproline and serum beta-glucuronidase activity in the acute, subacute, chronic and highly chronic stage of liver injury. The biochemical findings show continuously progressing damages when traumatization proceeds. In the 3-week test period the histological findings processed showed an increase in osteoclastic resorption in the alveolar bone around the occlusally stressed tooth simultaneously with a horizontal bone loss. Some indications of recovering incidents were seen, too. Only in the histological findings was no difference seen in the deterioration between both sexes, contrarily to the biochemical results also discussed in this study.

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Mitsuo Nakamura

Japanese Foundation for Cancer Research

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Harold Moe

University of Copenhagen

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Hidenori Tanaka

California State University

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