Biomedical subjects

E Alhava

Publications and source records attributed to E Alhava.

At least 19 recordsLinked to original sources

PubMed2001

Bone mineral metabolism after total gastrectomy.

Gastric surgery is mostly needed for treatment of gastric malignancy. To investigate the effect of total gastrectomy on bone mineral density (BMD) and bone mineral metabolism we evaluated 18 patients after total gastrectomy. Mean interval since operation was 71 +/- 20 months. BMD results were compared with age- and gender-matched controls (n = 46) and also expressed as T and Z scores. Bone mineral density measured by dual-energy X-ray absorptiometry (DXA) was found to be significantly lower in patients after total gastrectomy compared with healthy controls in the lumbar spine (p = 0.017 for women, p = 0.002 for men), femoral neck (p = 0.004 for women, p = 0.001 for men), Ward's triangle (p = 0.031 for women, p = 0.003 for men), and greater trochanter (p = 0.001 for women, p = 0.001 for men). Z scores for lumbar spine, femoral neck, Ward's triangle, and greater trochanter were -0.83, -1.54, -1.02, and -1.19, respectively. Biochemical measurements correlated poorly with BMD and were found to be of lesser value in diagnosing reduced bone mass as well as in differential diagnosis of etiology of osteopenia. The results of our study show the deleterious effect of total gastrectomy on bone mineral status and suggest an increased fracture risk in these patients.

Absorptiometry, Photon↗

PubMed2001

Expression of CD44 and its variant isoform v3 has no prognostic value in gastric cancer.

AIMS: To study the controversial role of transmembrane glycoprotein CD44 as a moderator of tumour spread and as a prognostic factor in gastric cancer. METHODS AND RESULTS: The expression of all CD44 forms and that with exon v3 was assessed in 198 stage I-IV gastric adenocarcinomas using immunohistochemistry. CD44 expression was found in 72% and CD44v3 in 55% of the cases. The intensity of CD44 expression was associated with the level of invasion and with hyaluronan expression, while the frequency of CD44 positive cells was not significantly related to any of the clinical or histological features of the tumours. CD44v3 expression failed to show any association with the clinical or histological variables examined. Neither total CD44 nor CD44v3 expression affected survival. The most important prognostic factors in this cohort were the level of invasion, lymph node status, tumour size and vascular or perineural invasion. CONCLUSIONS: Changes in CD44 or CD44v3 expression level do not predict tumour spread or patient survival in gastric cancer.

Adenocarcinoma↗

PubMed2001

Effects of systemic arterial hypoperfusion on splanchnic hemodynamics and hepatic arterial buffer response in pigs.

The hepatic arterial buffer response (HABR) tends to maintain liver blood flow under conditions of low mesenteric perfusion. We hypothesized that systemic hypoperfusion impairs the HABR. In 12 pigs, aortic blood flow was reduced by cardiac tamponade to 50 ml. kg(-1). min(-1) for 1 h (short-term tamponade) and further to 30 ml. kg(-1). min(-1) for another hour (prolonged tamponade). Twelve pigs without tamponade served as controls. Portal venous blood flow decreased from 17 +/- 3 (baseline) to 6 +/- 4 ml. kg(-1). min(-1) (prolonged tamponade; P = 0.012) and did not change in controls, whereas hepatic arterial blood flow decreased from 2 +/- 1 (baseline) to 1 +/- 1 ml. kg(-1). min(-1) (prolonged tamponade; P = 0.050) and increased from 2 +/- 1 to 4 +/- 2 ml. kg(-1). min(-1) in controls (P = 0.002). The change in hepatic arterial conductance (DeltaC(ha)) during acute portal vein occlusion decreased from 0.1 +/- 0.05 (baseline) to 0 +/- 0.01 ml. kg(-1). min(-1). mmHg(-1) (prolonged tamponade; P = 0.043). In controls, DeltaC(ha) did not change. Hepatic lactate extraction decreased, but hepatic release of glutathione S-transferase A did not change during cardiac tamponade. In conclusion, during low systemic perfusion, the HABR is exhausted and hepatic function is impaired without signs of cellular damage.

Animals↗

PubMed2001

Pamidronate increases trabecular bone mineral density in immobilization osteopenia in male rats.

BACKGROUND AND AIMS: Osteopenia is a common consequence of immobilization. We investigated the effects of pamidronate on immobilized bone in male rats. MATERIAL AND METHODS: Eighty male Wistar rats (5 months old) were divided in five groups (control (C); pamidronate at 0.5 mg/kg per dose (Pam0.5); immobilization (N); pamidronate at 0.05 mg/kg per dose + immobilization (N + Pam0.05); and pamidronate at 0.5 mg/kg per dose + immobilization (N + Pam0.5). The rats were immobilized on their right side by sciatic neurectomy. Pamidronate was given subcutaneously three times a week for three weeks. Trabecular bone mineral density (TBMD) of the upper femur, ultimate failure load of the femoral diaphysis, ash weight of femur, calcium content of femoral ash, and ash weight corrected with bone volume (AWcc [g/cm3]) were determined. Histomorphometry of proximal tibiae was performed by a semiautomatic method. RESULTS: TBMD was higher on both sides in Pam0.5 and N + Pam0.5 groups than in C or N groups. Ultimate failure load was not altered significantly with treatment. AWcc of the immobilized femur was lower (p < 0.001) than in the contralateral limb in N, N + Pam0.05 and N + Pam0.5 groups. Both resorption and formation parameters were suppressed by pamidronate. CONCLUSION: Pamidronate treatment seemed to increase trabecular bone density, although it was not effective in maintaining the AWcc of the operated extremity. Pamidronate did not seem to affect the ultimate failure load of cortical bone.

Animals↗

PubMed2000

Risk factors for perimenopausal fractures: a prospective study.

This prospective study was aimed at determining the risk factors for the development of fractures in perimenopausal women. The study group (n = 3068) was comprised of a stratified population sample of women aged between 47 and 56 years. During the follow-up period of 3.6 years, 257 (8.4%) of the women sustained a total of 295 fractures. After adjustment for covariates, the relative risk (RR) of sustaining a fracture was found to be 1.4 [95% confidence interval (CI) 1.2-1.6] for a 1 standard deviation (SD) decrease in the spinal and femoral neck bone mineral density (BMD). Women with a previous fracture history were found to have an increased risk of fracture [RR 1.7 (95% CI 1.3-2.2)] and those reporting three or more chronic illnesses exhibited a RR of 1.4 (95% CI 1.0-1.9). Women not using hormone replacement therapy (HRT) had a RR of 1.5 (95% CI 1.1-2.2) for all fracture types. When osteoporotic fractures (vertebral, hip, proximal humerus and wrist fractures; n = 98) were used as an endpoint, the independent risk factors were found to be a low BMD (RR for a 1 SD decrease in both spinal and femoral neck BMD was 1.6, 95% CI 1.3-2.0), a previous fracture history (RR 1.9, 95% CI 1.3-2.9) and nonuse of HRT (RR 2.2, 95% CI 1.3-4.0). The independent risk factors for all other fractures (n = 158) were a low BMD (RR for a 1 SD decrease in the spinal BMD was 1.4, 95% CI 1.2-1.6 and in the femoral neck BMD was 1.3, 95% CI 1.1-1.5), a previous fracture history (RR 1.6, 95% CI 1.1-2.2), smoking (RR 1.8, 95% CI 1.1-2.7) and having had three or more chronic illnesses (RR 1.6, 95% CI 1.1-2.2). Weight, height, age, menopausal status, maternal hip fracture, use of alcohol, coffee consumption or dietary calcium intake were not independently associated with the development of any particular type of fracture. We conclude that the independent risk factors for perimenopausal fractures are a low bone density, previous fracture history, nonuse of HRT, having had three or more chronic illnesses and smoking, the gradient of risk being similar for spinal and femoral neck BMD measurements in the perimenopausal population. The risk factors are slightly different for perimenopausal osteoporotic than for other types of fractures.

Analysis of Variance↗

PubMed2000

Risk factors for perimenopausal distal forearm fracture.

This prospective population-based cohort study investigated factors predicting distal forearm fracture (DFF) in perimenopausal women. The study population consisted of 11,798 women from the Kuopio Osteoporosis Risk Factor and Prevention (OSTPRE) Study in Finland. Mean baseline age of these women was 52.3 (SD 2.9) years (range 47-56 years) and 68% were postmenopausal. Three hundred and sixty-eight women (3.1%) had a validated DFF during the 5-year follow-up. Previous wrist fracture, postmenopausal state, age and nulliparity were independent predictors of DFF, while hormone replacement therapy (HRT), dairy calcium and overweight protected against it in multivariate Cox regression analysis: previous wrist fracture increased the DFF risk by 158% (p < 0.0001), menopause by 69% (p = 0.002) and age by 6% per year (p = 0.010), whereas the continuous use of HRT decreased the risk by 63% (p = 0.0001), the use of dairy calcium at 1000-1499 mg/day (vs < 500 mg/day) by 39% (p = 0.004), overweight (BMI > 25 kg/m2) by 36% (p = 0.0002) and parity by 29% (p = 0.031). Combining dichotomous low weight, low use of calcium, non-use of HRT and previous wrist fracture into a risk score gave a dose-response effect by score level: the presence (vs absence) of all four risk factors resulted in a 12-fold DFF risk. Nevertheless, the sensitivity and specificity of the score for detecting DFF remained low. It was concluded that HRT, high nutritional calcium intake and overweight protect against but a history of wrist fracture predisposes to perimenopausal distal forearm fracture. A simple risk factor inquiry would help to identify perimenopausal women at high risk of distal forearm fracture.

Cohort Studies↗

PubMed2000

Determinants of bone mineral density in middle aged men: a population-based study.

Osteoporosis is a growing health problem not only in women but also in men. To assess determinants of bone mineral density (BMD) at the spine and proximal femur, a randomly selected sample of 140 Finnish men aged 54-63 years was measured using fan beam dual-energy X-ray absorptiometry. Isometric muscle strength was measured using a computerized measurement system and cardiorespiratory fitness was assessed with maximal oxygen uptake (VO2 max) using breath-by-breath respiratory gas analyses during an incremental bicycle ergometer exercise. Intakes of calcium and energy were estimated using 4-day food records. Smoking habits and alcohol consumption were assessed from an interview and a 4 week diary, respectively. Isometric muscle strength of triceps and biceps brachii, extensors and flexors of thigh and rectus abdominis correlated significantly with BMD (r = 0.18-0.35, p = 0.02-0.000). Calcium intake correlated positively with femoral (r = 0.19-0.28, p = 0.03-0.003), but not with lumbar BMD. In addition, calcium intake adjusted for dietary energy content (mg/MJ) correlated with femoral BMD (r = 0.25-0.36, p = 0.03-0.000). Smoking had no effect on BMD, whereas alcohol intake correlated positively with BMD at L2-L4 (r=0.19, p = 0.031). In the multiple linear regression analysis adjusted calcium intake predicted BMD in every site measured, while strength of abdominal muscles predicted BMD at Ward's triangle and femoral neck. Body weight was a predictor of trochanteric BMD. Body height was the best predictor of lumbar and femoral neck area. We conclude that low dietary calcium intake, weak muscle strength and low body weight are risk factors for low BMD in men.

Absorptiometry, Photon↗

PubMed2000

Measurement of bone density around total knee arthroplasty using fan-beam dual energy X-ray absorptiometry.

The clinical survival of joint arthroplasties is clearly associated with the quality of surrounding bone environment. Bone mineral density (BMD) is an important measure of bone strength and quality. Periprosthetic BMD can be measured by using dual-energy X-ray absorptiometry (DXA) with special software algorithms. We studied short-term reproducibility of the periprosthetic BMD measurements after total knee arthroplasty (TKA) in 30 patients with primary osteoarthrosis. The operated knees and the contralateral control knees were measured twice and the results were expressed as a coefficient of variation (CV%). The average precision error was 3.1% in femoral regions of interest (ROI) and 2.9% in tibial ROIs after TKA. In the prosthesis-free control knees, CV% were similar; 3.2% and 2.5%, respectively. The best precision was found in the femoral diaphyses above the implant (1.3%), whereas the least reproducible BMD was determined in the patellar region of the TKA knees (6.9%). Our results confirm that DXA measures precisely small bone mineral changes around TKA and makes it possible to follow bone remodeling DXA and may provide a feasible method for monitoring TKA in the future.

Absorptiometry, Photon↗

PubMed2000

Bone loss around failed femoral implant measured by dual-energy X-ray absorptiometry.

Periprosthetic bone mineral density (BMD) and its changes after primary total hip arthroplasty (THA) have been studied extensively, but quantitative data on BMD around loosened prostheses are still lacking. In this study, using dual-energy X-ray absorptiometry (DXA), we determined periprosthetic BMD in 19 patients with failed primary THA. There was a decrease in BMD (8. 8%-25.5%) in every Gruen zone as compared with the patient's non-operated (control) side. Although the bone loss was most significant in the proximal femur, as in primary THA, the pattern of bone loss around the failed THA differred from the typical remodeling seen after successful THA. We suggest that quantitation of bone mass around the failed femoral stem is possible. Remarkable generalized bone loss around the stem is associated with a loosened prosthesis.

Absorptiometry, Photon↗

PubMed2000

Concordance of in vivo microdialysis and in vitro techniques in the studies of adipose tissue metabolism.

BACKGROUND: Adipose tissue metabolism can be investigated directly in vivo by microdialysis and indirectly in vitro using isolated adipocytes. The in vitro studies are relatively easy to make and they give information about specific tissue metabolism. The in vivo studies, on the other hand, are supposed to give relevant data about tissue physiology interacting with other metabolic systems at the body level. OBJECTIVE: To investigate the concordance between the results on responsiveness to stimulation of lipolysis from in vivo microdialysis and in vitro isolated adipocytes. SUBJECTS: Altogether 22 massively obese otherwise healthy subjects (seven men and 15 women, age 41 (26-55) y, BMI 51.5 (37.5-73.9)kg/m2, mean (range)) going through the gastric banding operation participated in the study. METHODS: The microdialysis study was done after an overnight fast at rest. Lipolysis was stimulated with isoprenaline that was perfused into the subcutaneous abdominal adipose tissue. Local blood flow was estimated by ethanol dilution method. Adipose tissue biopsy for the in vitro study was taken from subcutaneous abdominal region during the operation. Lipolysis in freshly isolated adipocytes was stimulated with different concentrations of adrenaline or isoprenaline. RESULTS: Significant positive correlations were observed between the values of relative stimulation of lipolysis in isolated adipocytes and in the microdialysis study. These correlations improved after correcting for cell size or fat mass. CONCLUSION: The microdialysis study in vivo and lipolysis assay with isolated adipocytes in vitro provide concordant and complementary information of adipose tissue metabolism in the same individual.

Adipocytes↗

PubMed2000

The morphological changes in rat bladder after photodynamic therapy with 5-aminolaevulinic acid-induced protoporphyrin IX.

OBJECTIVE: To assess the optimum light energy needed to induce only superficial bladder wall damage during photodynamic therapy (PDT) as a treatment for bladder cancer. Materials and methods The urinary bladder (with normal epithelium) of 64 female rats was treated with PDT using a continuous-wave argon-ion laser as an energy source and aminolaevulinic acid (ALA)-induced protoporphyrin IX photosensitizer. Four hours after the intravenous administration of ALA (300 mg/kg) the bladders were intravesically exposed to light fluences of 20-80 J/cm2. The control rats received no ALA and were exposed to 20 J/cm2 light. After 1, 3, 7 and 21 days the animals were killed and the morphological changes in bladder wall analysed both macroscopically and using light and scanning electron microscopy. RESULTS: At the dose of ALA given, a fluence of 20-40 J/cm2 caused mainly superficial damage, whereas 80 J/cm2 produced full-thickness injuries to the bladder wall. The maximum effect of PDT occurred after 1 and 3 days of irradiation. After 3 weeks of PDT the histology showed few full-thickness injuries and only in those treated with 80 J/cm2 light. CONCLUSION: These results indicate that PDT can be used to safely induce a selective superficial removal of bladder mucosa with no fibrotic effects on detrusor musculature, when optimum photosensitizing drug and fluences are used. These findings support the use of PDT in the therapy of superficial bladder cancer.

Aminolevulinic Acid↗

PubMed2000

The growth pattern and microvasculature of pancreatic tumours induced with cultured carcinoma cells.

Pancreatic cancer is one of the most frustrating problems in gastroenterological surgery, since there is little we can do to improve the survival of patients with current treatment strategies. If one is to elucidate factors related to carcinogenesis, tumour biology, diagnostics and new treatment modalities of this malignant disease, then it is essential to develop a suitable animal model. In the present study we investigated rat pancreatic tumour growth after intrapancreatic injection of cultured pancreatic carcinoma cells (DSL-6A/C1), originally derived from an azaserine-induced tumour, as well as the features of tumour microcirculation using the microangiography technique. After intrapancreatic inoculation, tumours were detected in 64% of animals. A 1 cm3 tumour volume was reached within 20 weeks after inoculation. The tumours were ductal adenocarcinomas. Larger tumours showed invasive growth and spreading into the surrounding tissues, mainly into spleen and peritoneum. Microangiography revealed that the pancreatic tumours had an irregular and scanty vessel network and there were avascular areas in the center of the tumour. The area between normal pancreas and the induced tumour had dense vascularization. Intrapancreatic tumour induction with cultured pancreatic carcinoma cells produced a solid and uniformly growing tumour in Lewis rats and it thus provides a possible model for pancreatic cancer studies.

Animals↗

PubMed2000

Pronounced differences in inhibition potency of lactone and non-lactone compounds for mouse and human coumarin 7-hydroxylases (CYP2A5 and CYP2A6).

1. The structural requirements for a compound to be a potent inhibitor for mouse CYP2A5 and human CYP2A6 enzymes catalysing coumarin 7-hydroxylase activity have been studied. 2. The IC50 of 28 compounds for the pyrazole-treated male DBA/2 mouse and human liver microsomal coumarin 7-hydroxylation were determined at 10 microm coumarin concentration 15 times over Km of coumarin. 3. The three most potent inhibitors for CYP2A5 were gamma-nonanoic lactone, gamma-decanolactone and gamma-phenyl-gamma-butyrolactone with an IC50 = 1.9+/-0.4, 2.1+/-0.2 and 2.4+/-0.3 microM and for CYP2A67-methylcoumarin, butylcyclohexane and indan with an IC50. = 30+/-3.2, 43+/-9 and 50+/-11 microM. 4. Among the 28 compounds studied, only 2-benzoxazolinone, 2-indanone and gamma-valerolactone showed similar inhibitory activity in both species. Indan had a lower IC50 for human than for mouse coumarin 7-hydroxylation, whereas the IC50 of 24 other compounds was higher for human than for mouse coumarin 7-hydroxylation. 5. The largest difference in IC50 between mouse and human activity was observed with 5-substituted phenyl, pentyl, hexyl, heptyl or octyl gamma-lactones or 6-substituted delta-lactones. IC50 of gamma-undecanolactone and gamma-decanolactone was 500 times lower for mouse than human coumarin 7-hydroxylation. 6. The difference in the IC50 between human and mouse coumarin 7-hydroxylation decreased substantially with the corresponding compounds without the lactone ring. 7. It is concluded that certain 5- or 6-position substituted gamma- and delta-lactones are potent inhibitors for mouse CYP2A5 but not for the orthologous human CYP2A6 and that the active site of CYP2A6 could be smaller than the active site of CYP2A5.

Animals↗

PubMed2000

Effects of dobutamine on splanchnic tissue perfusion during partial superior mesenteric artery occlusion.

OBJECTIVE: To evaluate the effects of dobutamine and fluid treatment on splanchnic hemodynamics and tissue oxygenation during partial superior mesenteric artery occlusion. DESIGN: Prospective, open randomized, full-factorial design. SETTING: University research laboratory. SUBJECTS: Forty-eight female pigs. INTERVENTIONS: In 24 anesthetized pigs (ischemic group), superior mesenteric artery (SMA) blood flow was reduced to 30% from the baseline for 120 mins; 24 pigs (sham group) served as nonischemic controls. The animals were further assigned into four treatment arms. In the control arm, the animals were administered only basic fluid therapy. In the fluid therapy arm, pulmonary artery occlusion pressure was maintained at 10 mm Hg with fluids. In the dobutamine treatment arm, dobutamine hydrochloride was infused at a dose of 10 microg/min/kg. In the combined dobutamine-fluid therapy arm, dobutamine at 10 microg/min/kg was administered and pulmonary artery occlusion pressure was maintained at 10 mm Hg with fluids. MEASUREMENTS AND MAIN RESULTS: Systemic and regional hemodynamics and oxygen transport, as well as jejunal intramucosal pH, intramucosal-arterial PCO2 gradient, and portal venous-arterial lactate gradient were measured. Ischemia did not modify the effects of fluids or dobutamine on systemic hemodynamics and oxygen transport. Dobutamine-treated animals had a higher cardiac index compared with control animals (218 +/- 22 vs. 135 +/- 13 mL/min/kg; p = .012), and the effect was enhanced when dobutamine was combined with fluid treatment (365 +/- 23 mL/ min/kg; p = .019). Fluid treatment alone did not influence cardiac index, whereas it increased SMA blood flow compared with control groups (15 +/- 2 vs. 12 +/- 2 mL/min/kg; p = .023). Dobutamine also decreased the proportion of SMA blood flow of cardiac output compared with control groups (6 +/- 1 vs. 9% +/- 1%; p = .024). Other treatments had no effect on SMA blood flow. Ischemia increased intramucosal-arterial Pco2 gradient to 54.8 +/- 10.7 torr (7.31 +/- 1.43 kPa) (p = .002 vs. sham control) and decreased intramucosal pH to 7.13 +/- 0.06 (p = .028 vs. sham control). In the ischemic animals, dobutamine without fluid therapy reduced intramucosal pH further to 7.00 +/- 0.09 (p = .023 vs. ischemic control) and increased portal venous-arterial lactate gradient (p = .033). CONCLUSIONS: Dobutamine alone worsened splanchnic tissue perfusion during partial superior mesenteric artery occlusion. As compared with fluid treatment alone, the combination of fluid and dobutamine therapy did not improve tissue perfusion.

Animals↗

PubMed2000

Prevention of systemic hyperlactatemia during splanchnic ischemia.

Arterial blood lactate increases as a result of poor tissue perfusion. In splanchnic hypoperfusion, increased hepatic lactate uptake may delay increases in arterial blood lactate. We hypothesized that during isolated reduction of mesenteric blood flow, maintaining systemic blood volume and flow by fluid resuscitation may prevent systemic hyperlactatemia and therefore mask splanchnic ischemia. In a randomized study, 7 pigs were subjected to 4 h of splanchnic hypoperfusion by reducing the superior mesenteric artery blood flow to 4 +/- 0.8 mL/kg min [mean +/- standard deviation (SD)]. Seven pigs served as controls. Fluid was administered in order to keep the pulmonary artery occlusion pressure at 5 to 8 mm Hg. Cardiac output, portal vein, superior mesenteric, and hepatic arterial blood flow were measured every 30 min. Arterial, mixed venous, hepatic, portal, and mesenteric venous blood lactate, and jejunal mucosal pCO2 were measured at baseline and thereafter at 30-min intervals. The initial decrease in portal venous blood flow in the ischemic animals was subsequently counterbalanced by increasing hepatic arterial blood flow from 2 +/- 1 mL x kg(-1) x min(-1) at baseline to 11 +/- 4 mL x kg(-1) x min(-1) [after 4 h of ischemia; mean +/- standard deviation (SD), P = 0.02]. Jejunal mucosal- and mesenteric vein-arterial pCO2 gradients increased in the ischemic group from 11 +/- 8 mm Hg to 73 +/- 5 mm Hg (P = 0.02), and from 10 +/- 4 mm Hg to 44 +/- 8 mm Hg, respectively (P = 0.02). Mesenteric and portal venous lactate increased in the ischemic animals from 1.1 +/- 0.3 mmol/L to 4.2 +/- 1.0 mmol/L (P = 0.02), and from 1.0 +/- 0.2 mmol/L to 1.6 +/- 0.3 mmol/L, respectively (P = 0,03). While mesenteric lactate production and hepatic lactate uptake increased in parallel in the ischemic animals from 5 +/- 6 micromol x kg(-1) x min(-1) to 14 +/- 5 micromol x kg(-1) x min(-1) (P = 0.04), and from 14 +/- 7 micromol x kg(-1) x min(-1) to 24 +/- 6 micromol x kg(-1) x min(-1), respectively (P = 0.02), hepatic venous and arterial lactate, and apparent splanchnic lactate uptake and extraction did not change. We conclude that the hepatic lactate uptake increases in response to hepatic lactate influx. Systemic hyperlactatemia and increased hepatic venous lactate concentrations are late consequences of mesenteric hypoperfusion if hypovolemia is prevented. The net exchange of lactate across the splanchnic region does not reflect hepato-portal lactate kinetics in this animal model of intestinal hypoperfusion.

Animals↗

PubMed2000

Expression and prognostic value of alpha-, beta-, and gamma-catenins indifferentiated thyroid carcinoma.

Catenins (alpha, ss, and gamma) are a group of intracellular cell adhesion molecules that unite cytoskeleton with extracellular adhesion system. Abnormal expression of these molecules may have prognostic relevance in various carcinomas, including differentiated thyroid carcinoma (DTC). We have, therefore, evaluated the prognostic value of alpha-, ss-, and gamma-catenins along with traditional risk factors in 206 consecutive DTC patients by immunohistochemistry. Papillary carcinomas showed normal staining pattern for alpha-, ss-, and gamma-catenins in 124 (60%), 136 (67%), and 94 (46%) cases, respectively. Follicular carcinomas expressed alpha-, ss-, and gamma-catenins normally in 16 (48%), 18 (55%), and 8 (32%) cases, respectively. Follicular type of tumor showed more often reduced staining for all catenins than papillary carcinoma (P: = 0.009, P: = 0.004, and P: = 0.002, respectively). Age (>60 yr) and pTNM-stage were related to reduced alpha- and ss-catenin expression levels (P: = 0.027 and P: = 0.026, respectively) and larger size of the tumor to reduced ss- and gamma-catenin expressions (P: = 0.039 and P: = 0.007, respectively). Nodal metastases at the time of primary treatment related to reduced alpha-catenin expression and distal metastases to reduced ss- and gamma-catenin staining signals (P: = 0.022, P: = 0.014, and P: = 0.039, respectively). Reduced alpha-catenin associated with tumor recurrence (P: = 0.002) and reduced ss-catenin with cancer-related mortality (P: = 0.005). The multivariate analysis for recurrence-free survival showed that alpha-catenin and serum thyroglobulin level 1 yr after primary treatment were prognostic of recurrent disease (hazards ratio, 3.42, P: = 0.022; and hazards ratio, 10.03, P: = 0.0001). In addition, alpha-catenin retained its prognostic significance in low-stage patients (P: = 0.0151). We propose that the evaluation of alpha-catenin expression by immunohistochemistry in DTC patients has prognostic value in addition to that obtained by traditional prognostic factors.

Aged↗

PubMed2000

Adenovirus-mediated gene transfer into an experimental pancreatic tumour.

BACKGROUND AND AIMS: Gene therapy has been suggested as a novel approach against pancreatic cancer, a disease with a grim prognosis with current modes of therapy. Despite recent advances in in vitro and experimental in vivo studies, there is no data available concerning gene transfer efficiency in intrapancreatic tumours in immunocompetent animal models. MATERIAL AND METHODS: In in vitro studies rat pancreatic carcinoma cells (DSL-6A/C1) were transduced with replication-deficient adenovirus carrying Escherichia Coli beta-galactosidase (lacZ) gene. Gene transfer efficacy was assessed at different multiplicities of infection (MOIs). Pancreatic tumours were induced by inoculating cultured DSL-6A/C1 cancer cells into Lewis rat pancreases. Established tumours were transduced and three days post-transduction, pancreatic tumours as well as other intra-abdominal organs were harvested and processed for histological analyses, including staining for marker gene expression. RESULTS AND CONCLUSIONS: In vitro assays showed that DSL-6A/C1 cells were transduced efficiently, even at low MOIs. In vivo gene transfer was successful in all animals, and all pancreatic samples showed reporter gene expression. Positive cells were detected in the peritumoural areas as well as to a lesser extent within the tumours. The transgene activity was not evenly distributed and the gene transfer efficiency varied from a few detectable blue cells to 11% per field. Our studies demonstrated safe in vivo gene transfer into intrapancreatic tumours, suggesting that pancreatic tumours are potential targets for in vivo delivery of therapeutic genes.

Adenoviruses, Human↗

PubMed1999

Improved gene transfer efficiency in liver with vesicular stomatitis virus G-protein pseudotyped retrovirus after partial liver resection and thymidine kinase-ganciclovir pre-treatment.

Liver-directed gene therapy is a promising alternative for the treatment of various liver diseases. Pseudotyped (VSV-G) retroviruses can be produced in high titres which is essential to overcome the problem of low gene transfer efficiency detected previously with first generation Moloney murine (MMLV) retroviruses and plasmid vectors. We compared the lacZ gene transfer efficiency of MMLV retroviruses and VSV-G retroviruses in Watanabe heritable hyperlipidaemic rabbit liver using an intraportal administration route. Hepatocyte proliferation was stimulated by a partial (10%) liver resection and a thymidine kinase-ganciclovir treatment. We also studied the safety of the gene transfer by clinical chemistry, tissue pathology and PCR analysis of lung, kidney, spleen and gonads. Gene transfer efficiency with the VSV-G retrovirus was significantly higher than with the traditional MMLV-based retrovirus (9.5+/-5.26 vs 0.21+/-0.10 positive hepatocytes mm(-2), P<0.05). After a 12-month follow-up period no lacZ expression was detected in liver samples. No transgene was detected in plasma or in lung, kidney, spleen and gonads by PCR analysis 7 days after gene transfer. Transient increases were found in plasma c-reactive protein, aspartyl aminotransferase and alanine aminotransferase levels shortly after the operation with both types of retroviruses. VSV-G retrovirus was well tolerated and may become an efficient new tool in liver gene therapy. The absence of transgene in systemic circulation or in extrahepatic tissues including gonads is an important safety feature required for in vivo gene therapy.

Animals↗