Biomedical subjects
Publications and source records attributed to M Talja.
In the treatment of 38 patients with urethral stricture, 21 received intralesional corticosteroid injections, combined in 17 cases with internal urethrotomy. The aetiology of the lesion is discussed, together with a review of the pertaining literature, and the results of the treatment are evaluated.
Indwelling urinary catheter may induce an inflammatory reaction or even stricture of the urethra. Catheter encrustation and urinary infection are other disadvantages associated with long-term catheterisation. In the present study, 77 male patients were catheterised randomly as part of their normal treatment with 1 of 3 different types of catheter: 22 siliconised latex, 28 hydrogel-coated latex and 27 full silicone catheters. The mean duration of catheterisation was 2.2 days. The urethral inflammatory reaction was assessed from cytological urethral swab specimens. Catheter encrustation was studied using scanning electron microscopic (SEM) analysis. The full silicone catheters induced the mildest degree of inflammation in the urethra, the percentage mean of inflammatory cells in smears being 20%. In both latex catheter groups the value was 36%. Neither the age of the patients nor the duration of catheterisation had any effect on the inflammatory reaction, which was more marked in patients with haemodynamic abnormalities. The hydrogel coating effectively prevented encrustation, while siliconised latex catheters were the least resistant to encrustation. The inflammatory reaction was variable in all patients. The use of urethral catheters should be restricted and suprapubic tubes should be used instead, particularly in patients with shock-like circulatory changes. By developing the biocompatibility and physical properties of urinary catheters, more compatible devices may be manufactured.
Modified Euro-Collins solution (ECS), which has been successfully used in kidney, liver and lung transplantation, was tested concerning myocardial and endothelial preservation in nine piglets. In six (group I), 1-hour cardiac arrest was induced with cold modified ECS, and in three (group II) heart-lung transplantation was performed, using modified ECS for graft preservation. In group I myocardial energy preservation was determined with biochemical assays for adenosine triphosphate, creatine phosphate, lactate and creatine 5, 15, 30 and 60 minutes after aortic clamping, and preservation of endothelium in the aorta and coronary arteries was studied with scanning electron microscopy. In group II electron microscopy was performed on endothelial samples from the ascending aorta and coronary and pulmonary arteries of the heart-lung block after excision, after 2 hours of ischemia, and after 1-2 hours of reperfusion. High-energy phosphates decreased progressively during the ECS cardioplegia in group I, and circulatory support was required during the post-transplantation reperfusion period in group II. The endothelial lining in all specimens was remarkably well preserved, however. Modified ECS flush thus was ideal for vascular endothelium but, because of its poor energy-preserving capacity, unsuitable for cardioplegia.
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We report a case where renal papillary necrosis caused ureteral obstruction. Sloughed papillary bodies could be successfully removed from the ureter using a rigid ureteroscope.
The management of urethral strictures is a challenge for surgery. In the present study the value of tunica vaginalis tissue for urethroplasty was investigated. 30 male rabbits were divided into two groups. In group I (11 animals) a urethral defect was covered with a tunica vaginalis patch (n = 6) or was left uncovered (n = 5). In group II (19 animals) a preoperative urethral stricture was induced by electrocoagulation through a urethroscope. The strictured urethra was plastied with tunica vaginalis (n = 9) or preputial (n = 10) patches. The results were analyzed after a period of 2 weeks to 5 months with radiographic, macroscopic and microscopic methods. The tunica vaginalis graft showed its superiority over the preputial graft: only 1 postoperative short stricture from 15 plasties (6 normal and 9 strictured urethrae) was found in the plastied group, whereas 2 strictures from 10 plasties were seen in the preputial patch group. In the urethral defect group, strictures were seen in 2 of 5 animals. The mesenchymal tunica vaginalis epithelium was covered with thin transitiocellular-like epithelium resembling transitiocellular layers. The present study supports the earlier findings on the use of tunica vaginalis tissue in urethroplasty.
Acute hemorrhagic pancreatitis was induced in 15 piglets, after which 8 of the piglets were treated with saline infusion only and 7 were treated with saline infusion and peritoneal lavage. Hemodynamic variables were measured hourly. Organ and peritoneal blood flow was determined at 0, 1, and 5 h with radioactive microspheres. Peritoneal morphology was studied at 0, 1, 3, and 5 h with light microscopy and scanning electron microscopy. According to the results, changes in cardiac output, mean blood pressure, and peritoneal blood flow and the peritoneal inflammatory reaction were similar in the two groups. However, a significant increase in heart rate and a significant decrease in the blood flow to the pancreas, liver, and spleen were observed in the saline group, in contrast to the lavage group. In addition, blood flow to the adrenal glands was significantly higher in the saline group after 1 h. In conclusion, peritoneal lavage prevented the increase in heart rate and the development of a significant decrease in pancreatic blood flow in experimental hemorrhagic pancreatitis. The significance of these findings remains to be further evaluated.
The changes in urethral blood circulation caused by hypovolemia were studied in male piglets to simulate the hemodynamic changes during extracorporeal perfusion used in open-heart surgery. Changes caused by mild pancreatitis were studied which produced a similar reduction in urethral blood flow measured by microspheres comparable to a 34% hemorrhage of the circulating blood volume. According to this study the urethral mucosa is very sensitive to hemodynamic changes. It may be the case that catheter toxicity is more significant when the urethral blood flow is diminished.
Eluates from 56 latex urinary catheters from seven manufacturers were divided into three categories according to covering material (siliconized, silicone elastomer coated and teflon coated) and tested for tissue toxicity by means of cell cultures based on the inhibition of DNA synthesis. The silicone elastomer coated catheters showed the lowest toxicity. Only 4 of 13 such catheters gave unacceptable toxic values, whereas half of the siliconized catheters were abandoned as toxic. Teflon and elastomer coatings had the best protective properties against toxic substances leaching from the catheter core. The surface contour of the catheters estimated by scanning electron microscopy (SEM) did not correlate with toxicity, whereas the cracks seen on the catheters did correlate with toxicity. The simple in vivo test methods used by the manufactures turned out to be insensitive to tissue toxicity testing of urinary catheters. The method used in this study was the most reliable for assessing the safety of latex urinary catheters. Thus manufacturers using multiple and in vitro cell culture tests had products of better quality than those using only a single test or simple in vivo tests.
Local effects of indwelling urinary catheters are poorly characterized. Latex catheter brands of various degrees of tissue toxicity were implanted into the urethra of 27 male piglets. The systemic hemodynamic states varied from normal to hypovolemia, where the circulation changes simulated the extracorporeal perfusion used in open-heart surgery. The urethral epithelial changes caused by the catheters were studied by light ad scanning electron microscopy (SEM). The blood circulation in paraurethral tissue reacted strongly to systemic hemodynamic changes. A reduced local blood flow induced an accumulation of polymorphonuclear leucocytes in the urethral epithelium and subepithelial space in connection with implanted latex urinary catheter strips. This was not seen in normovolemic piglets. Non-toxic wholly silicone control catheter implants did not induce changes. Epithelial cell damage correlated with the tissue toxicity values of implanted catheter strips. In SEM analysis destruction of microvilli and cell membranes was also discovered in connection with a latex catheter brand regarded as non-toxic. The wholly silicone catheters did not cause any detectable changes. The observed cell damage is induced by toxic chemicals dissolving from latex catheters. Local ischemia exacerbates these toxic effects and activates complement cascade. This induces polymorphonuclear granulocyte accumulation in the damaged urethral epithelium leading to demolition and urethral fibrotization. The present findings explain the etiology of the long urethral stricture epidemics seen in open-heart surgery in the early 1980s by showing the interference between indwelling latex catheters and reduced local blood flow.
Changes in peritoneal morphology were examined histologically and by scanning electron microscopy during porcine acute hemorrhagic (n = 8) and edematous (n = 9) pancreatitis and after intraperitoneal installation of hemorrhagic pancreatitis-associated peritoneal exudate in healthy piglets (n = 3). In all experimental groups peritoneal inflammatory changes with mesothelial damage were evident already 1 h after the induction of the disease, and increased with time. Hemorrhagic pancreatitis caused desquamation of mesothelial cells and denudation of the basal membrane. Intraperitoneal installation of hemorrhagic pancreatitis-associated peritoneal exudate in healthy piglets caused similar changes, whereas the changes in edematous pancreatitis were much less extensive. Peritoneal exudate accumulating in the peritoneal cavity during hemorrhagic pancreatitis caused early chemical peritonitis characterized by severe inflammation of the peritoneum with destruction of the mesothelial cell layer, leading to denudation of the underlying connective tissue. The significance of these changes in the pathophysiology of acute fulminant pancreatitis remains to be further studied.
The effect of profound hemorrhagic hypovolemia on cardiac output and pancreatic blood flow was studied in pigs with the thermodilution method and microsphere technique. Approximately 30-40% of the circulating blood volume was withdrawn slowly during 5 h. Cardiac output and pancreatic blood flow decreased by 35% and 32%, respectively. The animals underwent contrast-enhanced computed tomography (CT) before hypovolemia and at 5 h after its onset. The changes in systemic and local blood flow were related to the contrast enhancement of the pancreas. In spite of profound hypovolemia and a significant decrease in pancreatic blood flow (p less than 0.005), the contrast enhancement remained normal. The results of the present study indicate that pancreatic hypoperfusion caused by hypovolemia does not affect the contrast enhancement of the pancreas in CT.
In a randomized double-blind manner, 43 women with grade I and II stress urinary incontinence were treated with either phenylpropanolamine p.o. 50 mg twice daily (Rinexin, 1 tablet b.i.d.) or placebo during two weeks. Urethral CO2 profilometry, with recording of maximum urethral closure pressure (MUCP) and functional urethral length (FUL), and subjective response were considered for effect evaluation. The subjective response of Rinexin was highly significant (p = 0.01) above that of placebo. Clinical improvement was reported by 15 of 21 women on Rinexin and by 8 of 22 women on placebo. A significant increase in MUCP, 14%, was registered in women on Rinexin treatment. This increase was more pronounced in the grade I than in the grade II incontinent women. No statistically significant correlations were obtained between subjective response and increase in MUCP. An increase in FUL was recorded in both two treatment groups, but no statistically significant difference between them was obtained. Adverse drug reactions were rare. No changes in blood pressure occurred. Based on the present study, Rinexin (1 tablet b.i.d.) is an effective and safe medication for female grade I and II stress incontinence and is also recommended as adjunctive therapy to physiotherapy before Teflon injection or operation.
The tissue toxicity of 23 urinary catheter batches (6 latex and 2 non-latex brands) was tested in vitro and in vivo. In vitro, a human T-cell leukemia line (JM) was cultured in the presence of different concentrations of eluates made from the catheters. The cytotoxicity of the eluates was assessed from their ability to inhibit DNA synthesis measured by incorporation of 3H-thymidine. In vivo, two methods were used. Strips of catheters were implanted into the rabbit dorsal muscle and pieces of catheters were implanted into the rat peritoneal cavity. After four days, the foreign body reaction, type of inflammation and necrosis were quantified macroscopically and by light microscopy. The results of the in vitro cytotoxicity test were correlated with those of in vivo methods. The rat peritoneal implantation test correlated better with the cell culture test (P less than 0.01) than with the rabbit muscle implantation test (P less than 0.05). Based on the clinical experience of urethral stricture complications caused by urinary catheters, catheters yielding eluate which at 30% dilution inhibited 50% DNA synthesis were regarded as toxic. According to this, the rabbit muscle implantation test was not reliable in testing the tissue toxicity of urinary catheters, while the cell culture test was quantitative and seemed to correlate with both the rat peritoneal implantation test and with the clinical complications observed.
Severe urethral inflammatory reactions followed by strictures have been reported after short-term catheterisation with latex catheters since 1982. In this study a new method for assessing tissue toxicity is presented. It is based on the degree of inhibition of rat peritoneal foreign body reaction. Because the results are easier to interpret and more quantitative than those of the rabbit muscle implantation test, the rat peritoneal implantation test is recommended as a standard in vivo toxicity test.
After an epidemic of severe urethral strictures in cardiac surgery patients, all brand latex catheters marketed in Finland were investigated for cellular toxicity with eluates made from the catheters. Four of the seven brands, including the one involved in the stricture cases, showed marked cytotoxicity and inhibited almost all cell growth in various human cell cultures when a 30% catheter eluate was used. DNA histograms of cells cultured with toxic catheter eluate showed inhibition of DNA synthesis. Silicone catheters did not influence cell growth, which correlates with the finding that no new stricture cases were seen after the latex catheters were replaced with silicone ones. Attention is paid to the facts that international standards regarding urethral catheter toxicity are lacking and that catheter quality control is insufficient.
6 cases of renal oncocytomas are described. Preoperative diagnosis is difficult in spite of new clinical diagnostic methods. In our series oncocytoma was diagnosed angiographically in 1 case and in 3 cases carcinoma was suspected. 5 of 6 cases, reevaluated postoperatively, fulfilled three of the four criteria of Ambos et al. for oncocytoma. Ultrasonography is a good exclusion diagnostic method for renal neoplasms. Oncocytoma may be suspected if the tumor projects nearly totally outside the renal contour as we found in 3 of our 6 cases. Aspiration biopsy smears have a diagnostic value in the evaluation of renal neoplasms. Cytologically we preoperatively diagnosed oncocytoma in 1 of 3 cases in which biopsy was performed. We warn, however, about the mosaic pattern of renal neoplasms. Renal cell carcinomas may have large areas composed of oncocytes. Frozen section analysis is a potentially hazardous peroperative diagnostic method in large tumors if oncocytoma is suspected.