Enhanced cytotoxicity with interleukin-1 alpha and 5-fluorouracil in HCT116 colon cancer cells

Recombinant human interleukin-1 alpha (rIL-1 alpha), at concentrations that were not growth-inhibitory when given alone (100-10,000 U/ml), enhanced the growth inhibition resulting from a 72-h fluorouracil (FUra) exposure in HCT116 colon cancer cells. Median-effect analysis of clonogenic assays indicated that rIL-1 alpha, given 24 h prior to and following a 24-h exposure to FUra, increased lethality in a more than additive fashion. rIL-1 alpha did not appear to significantly affect [3H]-FUra metabolism, total [3H]-FUra-RNA incorporation or RNA retention after drug removal, inhibition of thymidylate synthase, or thymidine triphosphate pool depletion. During continuous exposure to rIL-1 alpha, transient stimulation of RNA and DNA synthesis was observed at 72 h, with a return to normal by 96 h. A 24-h exposure to 10 microM FUra altered the elution profile of newly synthesized DNA as monitored by pH step alkaline elution. An accumulation of lower-MW single-stranded DNA species was noted with FUra compared to control, accompanied by a significantly decreased proportion of DNA retained on the polycarbonate filter: 10% retained vs. 32% for control (P = 0.01). A 48-h exposure to rIL-1 alpha alone did not affect the elution profile of nascent DNA species, nor did it enhance the effects of FUra. Although FUra did not appreciably affect pulse [3H]-uridine incorporation into RNA for the initial 8-24 h of FUra exposure, progressive inhibition of net RNA synthesis was observed thereafter. FUra prevented the stimulatory effect of rIL-1 alpha on RNA synthesis, and net RNA synthesis was significantly inhibited (by 64-79% after 72 and 96 h) with the combination compared to rIL-1 alpha alone. Continuous exposure to 10 microM thymidine did not rescue cells from the lethality of FUra alone or the combination of FUra plus rIL-1 alpha, suggesting that depletion of deoxythymidine triphosphate as a consequence of thymidylate synthase inhibition was not the most important component of FUra toxicity. In contrast, 1 mM uridine provided partial protection against the toxicity of FUra alone or with rIL-1 alpha. Although uridine did not affect FUra metabolism, it decreased FUra-RNA incorporation by 42-60%, presumably as a consequence of the 2-fold expansion of UTP pools. [125I]-rIL-1 alpha binding was nonspecific; with a 24-h exposure, however, internalized [125I]-rIL-1 alpha exceeded cell surface-bound material by 2-fold.(ABSTRACT TRUNCATED AT 250 WORDS)     

The extracellular matrix molecule, laminin, induces purkinje cell dendritic spine proliferation in granule cell depleted cerebellar cultures

Some thyroid neoplasms notoriously cause problems in the histologic diagnosis of their nature (follicular versus papillary for example) or their malignant potential (adenoma versus carcinoma) because of overlapping histologic features. Here, thyroid lesions are presented according to their histologic presentation (vesicular, papillary, trabecular, solid or cystic patterns, fibrosing thyroids and lymphoid infiltrate). For each entity, the most discriminant histologic features are described with emphasis on the diagnostic pitfalls and their histological clues.     

Purification, characterization, and spasmogenic activity of neurotensin from the toad Bufo marinus

Neurotensin (NT) was isolated from an extract of the intestine of the cane toad, Bufo marinus and its primary structure established as: pGlu-Ala-Ile-Val-Ser-Lys-Ala-Arg-Arg-Pro-Tyr-Ile-Leu. This amino acid sequence shows five substitutions (Leu2 --> Ala, Tyr3 --> Ile, Glu4 --> Val, Asn5 --> Ser, and Pro7 --> Ala) compared with bovine NT. Synthetic Bufo NT (pD2 = 8.05 +/- 0.28) was equipotent and equally effective as bovine NT (pD2 = 8.24 +/- 0.38) in producing spasmogenic contraction of isolated segments of toad small intestine. However, the maximum response produced by Bufo NT was only 35 +/- 2% of that produced by substance P. The potencies, but not the maximum responses, to Bufo and bovine NT were significantly (p < 0.05) attenuated by pre-treatment with atropine but neither parameter was significantly diminished by tetrodotoxin and indomethacin. The data suggest that the action of NT involves interaction with receptors on toad intestinal smooth muscle that recognize the C-terminal region of NT (residues 8-13) that has been fully conserved during evolution of tetrapods. Contractile activity is mediated, at least in part, by release of acetylcholine.     

Health status of the over 60 years of age population and its relationship with sociodemographic factors (ANCO Project)

OBJECTIVE: To describe the health status of a population over 60 years and to study their relationship with several socio-demographic variables. DESIGN: A cross-sectional study, population based. SETTINGS: A community. PARTICIPANTS: A randomized sample of 1,103 non institutionalized people over 60 years living in the city of Cordoba (Spain). MEASUREMENTS AND MAIN RESULTS: By mean of a personal interview at home we used the OARS-MFAQ-VE questionnaire. Low self-rated health was associated with the age, to be female sex, a low cultural background, and a low income. Only 5.2% of the study people do not suffered any illness and 56% state that their health problems are major problems for doing their current activities. 4.9% declared to have some degree of physical incapacity. 3.7% of elderly population has an important cognitive deficit. CONCLUSIONS: The majority of elderly people has good health. Age is related with a poor health. Women have more health problems than men.     

Effect of acute increases in filtered HCO3- on renal hydrogen transporters: II. H(+)-ATPase

Adaptive increases in renal bicarbonate reabsorption occur in response to acute increases in filtered bicarbonate (FLHCO3). In a previous study, we showed that an increase in FLHCO3 induced by plasma volume expansion increased the Vmax for Na+/H+ exchange activity in renal cortical brush border membrane vesicles (BBMV), providing a potential mechanism for the adaptive increase in HCO3- reabsorption. The present studies were undertaken to determine whether the increase in FLHCO3 induced by plasma expansion also stimulates the other major H+ transporter in cortical BBMV, the H(+)-ATPase. H(+)-ATPase activity was assessed in BBMV obtained from hydropenic and plasma expanded Munich-Wistar rats, using a NADH-linked ATPase assay. H(+)-ATPase activity was measured as the ouabain and oligomycin-insensitive, bafilomycin A1-sensitive component of total ATPase activity. Acute plasma expansion doubled single nephron FLHCO3, and this change was associated with a 64% increase in the Vmax for H(+)-ATPase activity, with no change in apparent Km. The Vmax for H(+)-ATPase activity correlated directly with whole kidney GFR and FLHCO3 (r = 0.68 and 0.72, respectively), and with single nephron GFR and FLHCO3 (r = 0.76 and 0.80, respectively). Thus, the mechanism for the adaptive increase in proximal tubular HCO3- reabsorption that occurs in response to acute increases in FLHCO3 appears to be related to increased activity of both H(+)-ATPase and Na+/H+ exchange in the apical membrane of the proximal tubule epithelium.     

Phase II trial of 9-aminocamptothecin administered as a 72-hour continuous infusion in metastatic colorectal carcinoma

PURPOSE: The camptothecin derivative irinotecan has demonstrated clinical activity in metastatic colorectal carcinoma in both chemotherapy-naive and fluorouracil-refractory patients. 9-Aminocamptothecin (9-AC; NSC 603071), another camptothecin derivative, was selected for clinical development based on preclinical activity, including cures in human tumor xenografts resistant to standard anticancer agents. We report a phase II trial of 9-AC in patients with previously untreated metastatic colorectal carcinoma. PATIENTS AND METHODS: Colorectal cancer patients with measurable disease, a performance status of 0 to 2 (Zubrod), and no prior chemotherapy for metastatic disease received 9-AC. A cycle of therapy was 35 microg/m2/h for 72 consecutive hours (840 microg/m2/d for 3 days) and rest on days 4 to 14; a course of therapy was defined as two cycles (28 days). Patients were assessed for response after two courses. RESULTS: Seventeen patients with metastatic colorectal cancer were entered onto this trial. No complete or partial responses were noted. Treatment was well tolerated; toxic effects consisted mainly of neutropenia, nausea, vomiting, stomatitis, fatigue, and anemia. Grade 3 to 4 toxicity was limited to neutropenia (grade 3 in four patients and grade 4 in six), anemia (grade 3 in two patients), and vomiting (grade 3 in two patients). No grade 3 or 4 diarrhea occurred. Only two patients had their 9-AC dose reduced to 30 microg/m2/h. The median nadir absolute granulocyte count (AGC) was 1,500/microL. The median number of courses given was two and the median time to disease progression was 8 weeks. CONCLUSION: At the dose and schedule used in this trial, 9-AC lacked antitumor activity in metastatic colorectal cancer. 9-AC infusion schedules of longer duration are currently being investigated in this disease.     

Microwave-assisted extraction of phenolic antioxidant compounds from peanut skins

A microwave-assisted extraction system was used to extract phenolic antioxidants from peanut skins. The effects of microwave power (10%, 50%, 90% nominal), irradiation time (30, 90, 150 s) and sample mass (1.5, 2.5, 3.5 g) on total phenolic content (TPC), ORAC (oxygen radical absorbance capacity) level and resveratrol content of peanut skin extracts (PSE) were investigated. Peanut skins were extracted with 37.5 ml of 30% ethanol (EtOH) in water. A response surface method was used to estimate optimum extraction conditions, based on TPC, ORAC level and resveratrol content. The maximum predicted TPC, under the optimised conditions (90% microwave power, 30 s irradiation time and 1.5 g skins), was 143.6 mg gallic acid equivalent (GAE)/g skins. The highest ORAC value was 2789 μmol trolox equivalents (TE)/g skins, which occurred at 90% power, 150 s and 1.5 g of skins. Resveratrol was identified in PSE by LC–MS–MS analysis.     

Molecular modeling of immunoglobulin light chains implicates hydrophobic residues in non-amyloid light chain deposition disease

Light chain deposition disease is a severe complication of certain immunoproliferative disorders, due to the secretion of a monoclonal light chain which precipitates close to basement membranes of several tissues. A kappa isotype restriction and an unusual frequency of a variable region subgroup (VkappaIV) suggest that precise structural features govern the propensity of pathogenic light chains to precipitate in extracellular spaces. We studied primary structures of light chains from six patients with light chain deposition disease in comparison with light chains from other pathological conditions. Sequence alignment revealed the presence of certain amino acids only in light chain deposition disease, in particular non-polar replacing hydrophilic residues. To determine the role of these residues, structures of the variable domain from four kappa chains belonging to VkappaI and VkappaIV subgroups responsible for deposition disease were modeled using known immunoglobulins as templates. The most evident structural features shared by all pathogenic light chains were hydrophobic residues exposed to the solvent in complementarity determining regions 1 or 3. In contrast to immunoglobulin light chain- related amyloidosis, where deposition of organized material might be due to electrostatic interactions between light chain dimers, hydrophobic interactions could enhance amorphous precipitation in non- amyloid light chain deposition disease.      

Study on Composition Distribution and Ferromagnetism of Monodisperse FePt Nanoparticles

Monodisperse FePt nanoparticles with size of 4.5 and 6.0 nm were prepared by simultaneous reduction of platinum acetylacetonate and thermal decomposition of iron pentacarbonyl in benzylether. The crystallography structure, size, and composition of the FePt nanoparticles were examined by X-ray diffraction and transmission electron microscopy. Energy dispersive X-ray spectrometry measurements of individual particles indicate a broad compositional distribution in both the 4.5 and 6 nm FePt nanoparticles. The effects of compositional distribution on the phase-transition and magnetic properties of the FePt nanoparticles were investigated.