In vivo and in vitro responses to poly(ethylene terephthalate-co-diethylene glycol terephthalate) and polyethylene oxide blends

Although biocompatible polymeric compounds are generally nontoxic, nonimmunogenic, and chemically inert, implants made from these materials may trigger acute and chronic inflammatory responses. These inflammatory reactions may induce degeneration of implanted biopolymer. Interactions between implanted biomaterial and inflammatory cells are mediated by many cellular events involving cellular adhesion and activation. We studied the inflammatory responses in vivo and in vitro to samples of biopolymers composed of poly(ethylene terephthalate-co-diethylene glycol terephthalate) plus 0, 5, 25% of polyethylene oxide. We observed that these biopolymers did not induce inflammatory responses when implanted in the peritoneal cavity of mice for 28 days. However we observed deposition of hyaluronic acid at the surface of implanted biomaterial, suggesting that tolerance to biomaterial occurred after surgical implantation. No significant adhesion of inflammatory cells such as mononuclear phagocytes and peripheral leukocytes were observed in vitro, when poly(ethylene terephthalate-co-diethylene glycol terephthalate) blends were used as substratum to cellular adhesion. These results suggest that blends composed of poly(ethylene terephthalate-co-diethylene glycol terephthalate) induce low inflammatory cell adhesion, since no rejection of biopolymer was observed when implanted in experimental animal models.     

Wound botulism in heroin addiction]

Botulism is a rare disease which usually is caused by preformed botulinum toxin in food. However, this article describes a case of wound botulism in a 29-year-old male heroin addict who developed progressive diplopia, dysphagia and proximal weakness of skeletal limb muscles. He needed mechanical ventilation for two weeks. The clinical diagnosis of botulism was supported by neurophysiological tests. Assays for detection of botulinum toxin and Clostridium botulinum were negative. The patient had not eaten any contaminated food the last two weeks before symptoms appeared, but he had multiple contaminated skin wounds. After treatment with botulinum antitoxins and antibiotics he gradually recovered, and six weeks later he was discharged from hospital in good condition. To the best of our knowledge this is the first case of wound botulism reported in Norway.     

Loss of cell adhesion in Xenopus laevis embryos mediated by the cytoplasmic domain of XLerk, an erythropoietin-producing hepatocellular ligand

The erythropoietin-producing hepatocellular (Eph) family of ligands and receptors has been implicated in the control of axon guidance and the segmental restriction of cells during embryonic development. In this report, we show that ectopic expression of XLerk, a Xenopus homologue of the murine Lerk-2 (ephrin-B1) transmembrane ligand, causes dissociation of Xenopus embryonic blastomeres by the mid-blastula transition. Moreover, a mutant that lacks the extracellular receptor binding domain can induce this phenotype. The carboxyl-terminal 19 amino acids of the cytoplasmic domain of XLerk are necessary but not sufficient to induce cellular dissociation. Basic fibroblast growth factor, but not activin, can rescue both the loss of cell adhesion and mesoderm induction in ectodermal explants expressing XLerk. Collectively, these results show that the cytoplasmic domain of XLerk has a signaling function that is important for cell adhesion, and fibroblast growth factor signaling modulates this function.     

Correlation of chemiluminescent parameters of blood in non-irradiated animals with their survival after irradiation

Blood chemiluminescence is a reflection of the free radical oxidation process in every organism. The changes of its intensity, as a consequence of changes in the rate of this process, are connected, in its turn, with the changes, in the functional state of the organism. It is supposed that the differences in the radiosensitivity depend on the conditions in which free radical oxidation processes take place. Therefore, the indices of blood chemiluminescence of intact rats have been studied. The aim of the investigation is to find the correlations between these indices and the survival of animals irradiated with gamma-quantas in doses of 3.5, 7.0 and 9.0 Gr. It is established that the coefficients of the reaction rate (k1, k2 and k3) most reliably correlate with survival, whereas no correlation is observed between the other indices of chemiluminescence and survival.     

Dehydrocyanation of cultivars of lima bean (Phaseolus lunatus L) and its effect on tryptophan content

Three cultivars (red, black and white) of lima bean were studied to determine the best medium in which to cook them in order to reduce their hydrocyanic acid content to tolerable levels. The study also investigated the effects of processing media on the trytophan content of lima beans. Samples of each cultivar were parboiled in each of three media, 0.94 M HCl, 0.47 M H₂SO₄ and distilled water, for various times. Portions of each cultivar were also parboiled in the three media after enzyme incubation. Boiled samples were dried, pulverised and analysed for cyanide and tryptophan contents. There were 96.82, 99.78 and 99.62% reductions in cyanide content of the red cultivar after boiling in water, dilute HCl and dilute H₂SO₄ respectively for 30 min. The corresponding values for the white cultivar were 96.39, 99.59 and 94.77% respectively. Dehydrocyanation was more effective in enzyme‐incubated samples when they were parboiled in dilute mineral acids. The residual cyanide content in enzyme‐incubated samples was below tolerable limits after 30 min of treatment. However, the longer the parboiling time, the higher was the trytophan loss. Therefore parboiling for 30 min in dilute HCl will produce the desired result of insignificant residual cyanide content and minimal tryptophan loss in all samples. Copyright © 2004 Society of Chemical Industry     

Differences in the hormonal status of rats highly and poorly resistant to hypoxia

Rats were tested for hypobaric hypoxia and decapitated two weeks later at 9-12, 13-14 and 15-17 o'clock. The levels of corticosterone, insulin and testosterone were determined in serum by RIA. Great daily fluctuations and higher elevation of corticosterone level in response to additional 1.5-min hypoxia were observed in low hypoxia-resistant (HHR) rats. The correlation of corticosterone/insulin ratio was directly proportional in LHR rats and inversely proportional in HHR rats. No difference in testosterone and insulin levels in LHR and HHR rats was found.     

Long term prognosis after hepatectomy for hepatocellular carcinoma: a survival analysis of 204 consecutive patients

BACKGROUND: Intrahepatic recurrence continues to be the main cause of late death among hepatocellular carcinoma patients after hepatic resection. The aims of the current study were to identify the prognostic factors affecting long term survival and to evaluate the clinical value of pTNM classification as a prognostic factor for these patients. The identification of significant prognostic factors plays an important role in the selection of patients for postoperative adjuvant therapy and counseling. METHODS: From January 1989 to August 1995, 204 consecutive patients underwent hepatectomy for hepatocellular carcinoma. The overall cumulative and disease free survival rates for these patients were analyzed. Univariate and multivariate analyses of 16 clinicopathologic factors, including factors associated with pTNM classification, were performed to determine the significant prognostic factors. RESULTS: The median periods of overall cumulative survival and disease free survival were 35 months and 12.4 months, respectively. By univariate analysis, all factors associated with tumor (T) classification, namely, tumor size, vascular invasion, the number of tumor nodules, and tumor localization, were correlated with survival. By Cox regression analysis, preoperative indocyanine green retention value at 15 minutes, tumor size, and number of tumor nodules were independent prognostic factors of long term survival, whereas the number of tumor nodules, tumor size, and venous permeation were the most powerful predictors of tumor recurrence. The cumulative 5-year survival rates for patients with Stages I, II, III, and IVA tumors were 72%, 55%, 34%, and 8%, respectively. Significant differences in cumulative survival curves were observed among the categories of pTNM classification. CONCLUSIONS: The results of this study showed that pTNM classification correlated well with postoperative survival. Preoperative evaluation of hepatic functional reserve with an indocyanine green clearance test plays an important role in determining the long term prognoses of patients with hepatocellular carcinoma.     

Clinical applications of detecting dysfunctional p53 tumor suppressor protein

The p53 gene encodes for a protein, p53, which plays a critical role in controlling the cell cycle, in DNA repair and in programmed cell death (apoptosis). p53 is one of the most frequently mutated genes in human neoplasms and a variety of techniques have been developed to detect these mutations. These range from advanced molecular-genetic analyses to immunohistochemical staining for the p53 protein. This review will summarize our current understanding of the function of p53 as well as current methods to detect dysfunctional p53 and the clinical value of such analyses.