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Tumor-suppressor Pdcd4 inhibits transformation and invasion and is downregulated in cancers. So far, it has not been studied as to whether miRNAs, suppressing target expression by binding to the 3'-UTR, regulate Pdcd4 or invasion. The present study was conducted to investigate the regulation of Pdcd4, and invasion/intra-vasation, by miRNAs. A bioinformatics search revealed a conserved target-site for miR-21 within the Pdcd4-3'-UTR at 228-249 nt. In 10 colorectal cell lines, an inverse correlation of miR-21 and Pdcd4-protein was observed. Transfection of Colo206f-cells with miR-21 significantly suppressed a luciferase-reporter containing the Pdcd4-3'-UTR, whereas transfection of RKO with anti-miR-21 increased activity of this construct. This was abolished when a construct mutated at the miR-21/nt228-249 target site was used instead. Anti-miR-21-transfected RKO cells showed an increase of Pdcd4-protein and reduced invasion. Moreover, these cells showed reduced intra-vasation and lung metastasis in a chicken-embryo-metastasis assay. In contrast, overexpression of miR-21 in Colo206f significantly reduced Pdcd4-protein amounts and increased invasion, while Pdcd4-mRNA was unaltered. Resected normal/tumor tissues of 22 colorectal cancer patients demonstrated an inverse correlation between miR-21 and Pdcd4-protein. This is the first study to show that Pdcd4 is negatively regulated by miR-21. Furthermore, it is the first report to demonstrate that miR-21 induces invasion/intravasation/metastasis.

Objective: To compare banding ligation versus beta-blockers as primary prophylaxis in patients with esophageal varices and no previous bleeding., Methods: Randomized trials were identified through electronic databases, reference lists in relevant articles, and correspondence with experts. Three authors extracted data. Random effects meta-analysis and metaregression were performed. The reported allocation sequence generation and concealment were extracted as measures of bias control., Results: The initial searches identified 1,174 references. Sixteen trials were included. In 15 trials, patients had high-risk varices. Three trials reported adequate bias control. All trials reported mortality for banding ligation (116/573 patients) and beta-blockers (115/594 patients). Mortality in the two treatment groups was not significantly different in the trials with adequate bias control (relative risk 1.22, 95% CI 0.84-1.78) or unclear bias control (RR 1.02, 95% CI 0.75-1.39). Trials with adequate bias control found no significant difference in bleeding rates (RR 0.86, 95% CI 0.55-1.35). Trials with unclear bias control found that banding ligation significantly reduced bleeding (RR 0.56, 95% CI 0.41-0.77). Both treatments were associated with adverse events. In metaregression analyses, the estimated effect of ligation was significantly more positive if trials were published as abstracts. Likewise, the shorter the follow-up, the more positive the estimated effect of ligation., Conclusions: Banding ligation and beta-blockers may be used as primary prophylaxis in high-risk esophageal varices. The estimated effect of banding ligation in some trials may be biased and was associated with the duration of follow-up. Further high-quality trials are still needed.

The essential oils of two species of Sideritis growing spontaneously in Bulgaria and Macedonia are reported, Sideritis scardica and Sideritis raeseri. The oils of S. scardica from different locations differed significantly: in the Macedonian sample alpha-cadinol (20%) predominated, while in the oil of Bulgarian samples the main components were diterpenic compounds and octadecenol (over 20%). This is the first report of ditrpenoids in essential oil of S. scardica. The oil of S. raeseri demonstrated a distinct chemical profile with its high concentration of sesquiterpenes, main components being germacrone (25%) and elemol acetate (15.9%). The observed qualitative variability of the oil composition of S. scardica of different geographic origin could be a result of different ecologic conditions but might also reflect the well-known tendency of some Sideritis species to hybridize.

Background: The number of publications on clinical trials is unknown as well as the countries publishing most trial reports. To try to examine these questions we performed an ecological study., Methods: We searched the 454,449 records on publications in The Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, Issue 3, 2005 (CD-ROM version) for possible country of origin. We inspected a random sample of 906 records for information on country and type of trial., Results: There was an exponential growth of publications on randomised controlled trials and controlled clinical trials since 1946, but the growth seems to have seized since 2000. We identified the possible country of origin of 210,974 publications (46.4%). The USA is leading with about 46,789 publications followed by UK, Germany, Italy, the Netherlands, Canada, and France. Sweden becomes the leader with 891 publications per million inhabitants during the last 60 years followed by Denmark (n = 864), New Zealand (n = 791), Finland (n = 781), the Netherlands (n = 570), Switzerland (n = 547), and Norway (n = 543). In depth assessment of the random sample backed these findings., Conclusion: Many records lacked country of origin, even after the additional scrutiny. The number of publications on clinical trials increased exponentially until the turn of the century. Rather small, democratic, and wealthy countries take the lead when the number of publications on clinical trials is calculated based on million inhabitants. If all countries produced the same number of trials as these countries, this could mean thousands of new effective treatments during the next 60 years.

Background: Colorectal cancer may be prevented by reducing the development of adenomatous polyps., Aim: To assess the benefits and harms of antioxidant supplements in preventing colorectal adenoma., Methods: Using the Cochrane Collaboration methodology we reviewed all randomized clinical trials comparing antioxidant supplements with placebo or no intervention. We searched electronic databases and the reference lists until October 2005. Outcome measures were development of colorectal adenoma adverse events. We analysed dichotomous outcomes with fixed- and random-effects model meta-analyses and calculated the relative risk with 95% confidence interval., Results: We identified eight randomized trials (17 620 participants). Neither fixed-effect (relative risk: 0.93, 95% CI: 0.81-1.1) nor random-effect model meta-analyses (0.82, 0.60-1.1) showed statistically significant effects of supplementation with beta-carotene, vitamins A, C, E and selenium alone or in combination. Antioxidant supplements seemed to increase the development of colorectal adenoma in three low-bias risk trials (1.2, 0.99-1.4) and significantly decrease its development in five high-bias risk trials (0.59, 0.47-0.74). The estimates difference is significant (P < 0.0001). There was no significant difference between the intervention groups regarding adverse events, including mortality (0.82, 0.47-1.4)., Conclusion: We found no convincing evidence that antioxidant supplements have significant beneficial effect on primary or secondary prevention of colorectal adenoma.

The Wnt signaling pathway is activated by mutations in the adenomatous polyposis coli (APC) or beta-catenin genes in most colon cancers, leading to the transactivation of promoters containing binding sites for the Tcf/LEF family of transcription factors. We have previously shown that it is possible to confer colon cancer specificity on autonomous parvoviruses by inserting Tcf sites into the viral P4 promoter. The mutant Tcf promoters were responsive to activation of the Wnt pathway but the viruses replicated poorly. We show here that reduction of the number of Tcf sites from four to two leads to an increase in the efficiency of replication and toxicity of the viruses in Co115 colon cancer cells, with only a small reduction in selectivity for cells with an active Wnt signaling pathway. Despite this improvement, virus production by most colon cancer cells remained low. Analysis of parental phH1 virus infection of SW480 colon cancer cells showed that the nonstructural and capsid proteins were expressed, but single stranded DNA and progeny virus were not produced. This defect reflects the dependence of autonomous parvoviruses on host functions for many steps in their replication cycle and represents a major limitation to the use of selectively replicating parvoviruses for colon cancer therapy.

Background: Oxidative stress may cause gastrointestinal cancers. The evidence on whether antioxidant supplements are effective in preventing gastrointestinal cancers is contradictory., Objectives: To assess the beneficial and harmful effects of antioxidant supplements in preventing gastrointestinal cancers., Search Strategy: We identified trials through the trials registers of the four Cochrane Review Groups on gastrointestinal diseases, The Cochrane Central Register of Controlled Trials on The Cochrane Library (Issue 1, 2003), MEDLINE, EMBASE, LILACS, and SCI-EXPANDED from inception to February 2003, and The Chinese Biomedical Database (March 2003). We scanned reference lists and contacted pharmaceutical companies., Selection Criteria: Randomised trials comparing antioxidant supplements to placebo/no intervention examining the incidence of gastrointestinal cancers., Data Collection and Analysis: Two reviewers independently selected trials for inclusion and extracted data. The outcome measures were incidence of gastrointestinal cancers, overall mortality, and adverse events. Outcomes were reported as relative risks (RR) with 95% confidence interval (CI) based on fixed and random effects meta-analyses., Main Results: We identified 14 randomised trials (170,525 participants), assessing beta-carotene (9 trials), vitamin A (4 trials), vitamin C (4 trials), vitamin E (5 trials), and selenium (6 trials). Trial quality was generally high. Heterogeneity was low to moderate. Neither the fixed effect (RR 0.96, 95% CI 0.88 to 1.04) nor random effects meta-analyses (RR 0.90, 95% CI 0.77 to 1.05) showed significant effects of supplementation with antioxidants on the incidences of gastrointestinal cancers. Among the seven high-quality trials reporting on mortality (131,727 participants), the fixed effect (RR 1.06, 95% CI 1.02 to 1.10) unlike the random effects meta-analysis (RR 1.06, 95% CI 0.98 to 1.15) showed that antioxidant supplements significantly increased mortality. Two low-quality trials (32,302 participants) found no significant effect of antioxidant supplementation on mortality. The difference between the mortality estimates in high- and low-quality trials was significant by test of interaction (z = 2.10, P = 0.04). Beta-carotene and vitamin A (RR 1.29, 95% CI 1.14 to 1.45) and beta-carotene and vitamin E (RR 1.10, 95% CI 1.01 to 1.20) significantly increased mortality, while beta-carotene alone only tended to do so (RR 1.05, 95% CI 0.99 to 1.11). Increased yellowing of the skin and belching were non-serious adverse effects of beta-carotene. In four trials (three with unclear/inadequate methodology), selenium showed significant beneficial effect on gastrointestinal cancer incidences., Reviewers' Conclusions: We could not find evidence that antioxidant supplements prevent gastrointestinal cancers. On the contrary, they seem to increase overall mortality. The potential cancer preventive effect of selenium should be studied in adequately conducted randomised trials.

There are scanty of available data about the management of myoma of the uterus during pregnancy and birth. The authors describe two cases of such a pathology--big myoma of the uterus > 10 sm diameter (d.), who were treated conservatively and ended successfully, without serious complications. The pregnant women were done cesarean section and during the operation the myomas were excisiert. There were no complications intra- and postoperationem. The authors suggest that myectomy during pregnancy and cesarean section must not be don routinely.

Berberine (BB) is a protoberberine alkaloid derived from various representatives of the Berberidaceae family. Although used as a therapeutic agent, it has not been applied in the treatment of immune-mediated disorders. In the present study, BB was administered at a daily dose of 10 mg/kg for 3 consecutive days before the induction of tubulointerstitial nephritis (TIN) by injection of bovine tubular basement membrane (TBM) antigen in BALB/c mice. The animals were investigated 2 months after TBM inoculation. The intensity of pathological injuries in animals with TIN+BB decreased significantly, an effect that correlated with the improvement of renal function. Flow cytometric analysis of peripheral blood cells showed that BB caused a decrease in the number of CD3(+), CD4(+), CD8(+), and sIg(+) lymphocytes in comparison with TIN mice. The same tendency was noticed in the lymphocytes from kidney infiltrates of treated animals. The control animals treated only with BB showed a decrease in the number of CD3(+), CD4(+), CD8(+) T-lymphocytes in comparison with control nontreated mice. Our results, thus, indicate that BB has an immunosuppressive effect in the TIN model, which is an analogue of various human kidney autoimmune diseases.

Evidence shows that the quality of randomized clinical trials (RCTs) affects estimates of intervention efficacy, which is significantly exaggerated in low-quality trials. The present study examines the quality of all 235 RCTs published in HEPATOLOGY from the initiation in 1981 through August 1998. Quality was assessed by means of a validated 5-point scale and separate quality components associated with empirical evidence of bias. Only 26% of all RCTs reported sample size calculations, 52% adequate generation of the allocation sequence, 34% adequate allocation concealment and 34% double-blinding. The median quality score of all trials was 3 points (range, 1-5 points). Multiple logistic regression analysis explored the association between quality and therapeutic areas, number of centers, external funding, year of publication, and country of origin. High-quality trials were most likely to investigate portal hypertension (odds ratio [OR]: 2.4; 95% CI: 1.1-5.5; P =.03), be multicentered (OR: 3.4; 95% CI: 1.3-8.9; P =.01), sponsored by public organizations (OR: 4.2; 95% CI: 2.1-8.6; P =.0001), or the drug and device industry (OR: 4.7; 95% CI: 2.2-10.2; P =.0001) compared with other therapeutic areas, single-center trials, and trials with no external funding. Quality did not improve with time and was not associated with country of origin. The main conclusions are that the quality of RCTs in HEPATOLOGY needs improvement and that the probability of high quality increased with the number of centers involved and external funding.

A novel thermostable protein inhibitor of trypsin and subtilisin, called BN, was isolated from the seeds of Brassica nigra. The purified protein gave a single band on SDS-PAGE, corresponding to a molecular mass of 15 500 +/- 1000 Da. The inhibitor is composed of two disulfide-linked polypeptide chains, consisting of 39 and 90 residues, respectively. The amino acid sequence of the two chains was determined by Edman degradation of peptides, isolated from enzyme hydrolysates with TPCK-trypsin, EndoLysC proteinase and a Glu-specific proteinase of reduced and vinylpyridinated protein samples. A segment of the 'heavy' chain, between residues 65 and 81, showed homology with the reactive site loop region of the 6-kDa trypsin inhibitors from Nicotiana alata. The basic residue in position 39 (N. alata) or 70 (napins) is conserved as arginine or lysine in all inhibitors from N. alata and in all napins hitherto sequenced. Probably, the two families of trypsin inhibitors have structurally similar reactive sites. BN exhibits an extremely high thermostability: CD measurements showed that during heating to 97 degrees C it preserves a considerable part of the polypeptide backbone folding. Studies on the fluorescence properties of the inhibitor BN in the absence and presence of neutral or ionic quenchers demonstrated that the intrinsic emission of this protein is dominated by a tryptophyl residue, buried in the interior of the protein matrix. 20% of the light absorbed by Tyr 63 of the 'heavy' chain is transferred to Trp 26 of the 'light' chain.

The effect of leukaemia inhibitory factor (LIF) on the proliferation of prospermatogonial stem cells was tested in vitro. Pieces of 3-day-old rat testis were cultured in the presence of a range of doses of LIF alone or in combination with 1 ng mL(-1) seminiferous growth factor (SGF). Stimulation of the proliferative activity of quiescent prospermatogonia was detected immunocytochemically with a cell proliferation kit. After 24 h culture, LIF significantly increased the percentage of labelled prospermatogonia, with the peak of activity at 20 pg mL(-1). The combination of LIF and SGF resulted in a decrease in DNA synthetic activity of the germ cells. Hence, LIF and SGF play a role in local regulation at the onset of spermatogenesis in the rat testis.

The effect of proteins secreted by cultured pre-pubertal rat Sertoli cells (pSCP) on natural killer (NK) cell activity of rat, mice and guinea pig splenocytes and human peripheral blood lymphocytes was estimated. The results indicate that pSCP inhibited, in a dose-dependent manner, NK cell activity of mice, guinea pig and human lymphocytes but did not suppress lysis of YAC-1 target cells by rat NK cells. Species-specific differences in the effect of pSCP on NK cell activity probably result from differences in the binding of proteins within the effector cells. These data indicate that in the pre-pubertal period of gonadal development immature Sertoli cells synthesize a factor/s which might contribute to the maintenance of specific testis immunological environment.

Single doses of anticancer drug biocarbazine (BC)--DTIC synonym--were injected intraperitoneally at 50 and 200 mg/kg body weight to sexually mature BALB/c mice. Among other features previously reported (Martinova et al. 1989) BC causes ultrastructural alterations in spermatogonia and spermatocytes significantly expressed after administration of higher dose. In addition BC induces some defects in acrosome formation of early spermatids in Golgi and cap phase, while spermatids in later stages of maturation showed marked resistance to BC treatment.

The quick increase of morbidity, caused by the endometrial carcinoma in our country during recent 15 years from 5,2 to 16,5 per 100,000 raises acutely the question about effective primary and secondary prophylaxis. Having in mind the role of hyperestrogenemia in the etiology of endometrial carcinoma and the fact that the results from its treatment are determined basically by the degree of distribution of the tumor, the authors think that it is necessary fight for rational feeding, timely treatment of the disease with hyperestrogenemia and prophylactic therapy with gestagens. Cytologic examination of aspirate, obtained from the uterine cavity, is proposed as screening method for women of the risk groups. A scheme of management of women with pathological R3-5 group is proposed.

Biocarbazin (DTIC synonym) is an anticancer drug acting as a purine analogue, as an alkylating agent, as a SH-group blocker. Biocarbazin administration in doses 50 and 200 mg/kg of body weight to adult male BALB/c mice suppresses the process of spermatogenesis. Seminiferous tubule of the testis displayed dose-dependent histological alterations manifested with decrease of mitotically dividing cells and increase in the number of multinucleated spermatocytes and spermatids. RNA synthetic activity studied by means of autoradiography showed a tendency for a reduction in the spermatogonia and pachytene spermatocytes.