Coumarin chemoprotection against aflatoxin B1-induced gene mutation in a mammalian cell system: a species difference in mutagen activation and protection with chick embryo and rat liver S9

The prevalence of circulating cytomegalic endothelial cells, detected currently by the pp65-antigenemia assay and described previously in blood of transplanted and AIDS patients with disseminated human cytomegalovirus (HCMV) infection, was found to be 2.9% in the AIDS population and 6.5% in the fraction of the AIDS population with HCMV in blood. Cytomegalic endothelial cells increased to 39.7% and 48.4%, respectively, in AIDS patients with very high levels of antigenemia and viremia, while an end organ disease reached an incidence of 76.4%. Positive and negative predictive values of cytomegalic endothelial cell detection for diagnosis of HCMV end organ disease were 73.1% and 21.4% with antigenemia levels > 1,000, respectively. On the other hand, in a selected group of 38 cytomegalic endothelial cell-positive AIDS patients with < 50 CD4+ T cells/microliter and late-stage HCMV disease, who were followed-up for variable periods of time, the prevalence of high level antigenemia was 95.3%, that of viremia 86.0% and that of L-DNAemia 92.7%, while the incidence of HCMV end organ disease was 84.2%. In this population, it was shown that cytomegalic endothelial cell presence was associated with lack of (56.0% of episodes) or insufficient (4.0%) anti-HCMV treatment or emergence of HCMV drug-resistant strains (17.3%) or short-term response to antiviral treatment (22.7%); was determined in the same patient by different conditions during follow-up. Longitudinal observations indicated that cytomegalic endothelial cells were detected often in blood at least 3 months later than end organ disease suggesting that the duration of end organ disease was a cofactor associated with the appearance of cytomegalic endothelial cells.     

Content-based image retrieval at the end of the early years

Presents a review of 200 references in content-based image retrieval. The paper starts with discussing the working conditions of content-based retrieval: patterns of use, types of pictures, the role of semantics, and the sensory gap. Subsequent sections discuss computational steps for image retrieval systems. Step one of the review is image processing for retrieval sorted by color, texture, and local geometry. Features for retrieval are discussed next, sorted by: accumulative and global features, salient points, object and shape features, signs, and structural combinations thereof. Similarity of pictures and objects in pictures is reviewed for each of the feature types, in close connection to the types and means of feedback the user of the systems is capable of giving by interaction. We briefly discuss aspects of system engineering: databases, system architecture, and evaluation. In the concluding section, we present our view on: the driving force of the field, the heritage from computer vision, the influence on computer vision, the role of similarity and of interaction, the need for databases, the problem of evaluation, and the role of the semantic gap     

Behavior problems of residents with dementia in special care units

188 patients with high-turnover type post-menopausal osteoporosis were treated for 18 months with 4 different treatment regimens of S-calcitonin nasal spray. For a total of 18 months group 1 was given 100 IU/day, continuously; group 2, 100 IU/day daily for 30 days every other month ("ciclically"); group 3, 200 IU/day continuously, and group 4, 200 IU/day, ciclically. To monitor the effects of treatment, MOC of L2-L4, as well as serum osteocalcin and urinary hydroxyproline: creatinine levels were measured, on initiation of therapy, then at 9, 12 and 18 months, and finally at 6 and 12 months after completion of therapy. Analysis of the results yields the following major points: (A) The peak increase in bone mass occurs at 9 months the continuous therapy groups, and at 18 months in the cyclic therapy groups. In absolute values, the peak are higher in the continuous groups than in the cyclic groups. (B) The long-term increase in bone mass (measured at one year after completion of therapy) does not differ significantly between cyclic and continuous treatment groups at the same dosage. (C) During treatment, a dose-effect relationship exist when comparing dosages of 100 IU/day and 200 IU/day. However, this disappears by one year after completion of therapy. (D) There seems to be a "rebound effect" on osseous turnover after cessation of S-calcitonin therapy. The magnitude and rapidity of onset of this effect appear to correlate directly with the dosage of S-calcitonin administered.     

Nonnuclear effects of the steroid hormone 1 alpha,25(OH)2-vitamin D3: analogs are able to functionally differentiate between nuclear and membrane receptors

The steroid hormone 1 alpha,25-dihydroxyvitamin D3 [1 alpha,25(OH)2D3] stimulates biological responses via both genomic mechanisms and nongenomic mechanisms (opening of voltage-gated Ca2+ channels). We report here that the two closed B-ring steroid analogs of 1 alpha,25(OH)2D3, 1 alpha,25(OH)2-7-dehydrocholesterol and 1 alpha,25(OH)2-lumisterol3, are able to generate the nongenomic response, transcaltachia, without the ability to compete with the natural metabolite for binding to its nuclear receptor. We propose that the nongenomic membrane associated receptor can accept the ligand in its closed "6-s-cis" conformation whereas the nuclear receptor prefers the extended "6-s-trans" conformer.     

Modulated structures in Ni–Al–Cr alloy

The crystal structures of the different modulated and layered martensites in Ni–Al–Cr alloy have been observed. The layered martensite can be well described by the L1₀ lattice with seven‐layered or five‐layered long‐period stacking of {110} close‐packed planes of the parent phase. Modulated martensite is considered as a lattice oscillation by shuffling of atoms.     

Characterization of the cytoprotective action of peroxynitrite decomposition catalysts

The formation of the powerful oxidant peroxynitrite (PN) from the reaction of superoxide anion with nitric oxide has been shown to be a kinetically favored reaction contributing to cellular injury and death at sites of tissue inflammation. The PN molecule is highly reactive causing lipid peroxidation as well as nitration of both free and protein-bound tyrosine. We present evidence for the pharmacological manipulation of PN with decomposition catalysts capable of converting it to nitrate. In target cells challenged with exogenously added synthetic PN, a series of metalloporphyrin catalysts (5,10,15,20-tetrakis(2,4,6-trimethyl-3, 3-disulfonatophenyl)porphyrinato iron (III) (FeTMPS); 5,10,15, 20-tetrakis(4-sulfonatophenyl)porphyrinato iron (III) (FeTPPS); 5,10, 15,20-tetrakis(N-methyl-4'-pyridyl)porphyrinato iron (III) (FeTMPyP)) provided protection against PN-mediated injury with EC50 values for each compound 30-50-fold below the final concentration of PN added. Cytoprotection was correlated with a reduction in the level of measurable nitrotyrosine. In addition, we found our catalysts to be cytoprotective against endogenously generated PN in endotoxin-stimulated RAW 264.7 cells as well as in dissociated cultures of hippocampal neurons and glia that had been exposed to cytokines. Our studies thus provide compelling evidence for the involvement of peroxynitrite in cytokine-mediated cellular injury and suggest the therapeutic potential of PN decomposition catalysts in reducing cellular damage at sites of inflammation.     

IGF-I and vanadate stimulate Na/Pi-cotransport in OK cells by increasing type II Na/Pi-cotransporter protein stability

The nitric oxide (NO) signaling system, consisting of NO synthases, soluble guanylyl cyclase, and cGMP, plays a prominent role in salt handling and regulation of blood pressure. Soluble guanylyl cyclases are heme-containing heterodimers (alpha/beta). The alpha1/beta1 isoform has greater NO sensitivity than the alpha1/beta2. It has recently been shown that expression of the beta subunits is altered in the kidney of the Dahl salt-sensitive rat, ie, the beta1 subunit is decreased and the beta2 subunit increased. However, whether soluble guanylyl cyclase is linked to salt sensitivity is not known. In the present study, we investigated linkage of guanylyl cyclase genes to blood pressure. Alpha1 and beta1 gene loci for soluble guanylyl cyclase were mapped to rat chromosome 2, and the beta2 gene locus was mapped to rat chromosome 5 using fluorescent in situ metaphase hybridization. By use of a rat radiation hybrid panel, the gene loci were then further mapped with respect to known quantitative trait locus markers of salt-sensitive hypertension in the Dahl rat on chromosomes 2 and 5. Genes for alpha1 and beta1 were closely linked by two-point analysis to Na+,K+-ATPase alpha1 isoform (LOD of 15.1 and 14.0, respectively) and calmodulin-dependent protein kinase II-delta loci (LOD of 14.3 and 12.9, respectively), which have been previously shown to flank a quantitative trait locus for blood pressure in the Dahl rat. The alpha1 and beta1 genes were closely linked (LOD of 11.3; theta, 0.4). The beta2 gene locus was closely linked to the endothelin-2 (ET-2) locus (LOD of 13.0), which has been shown to cosegregate with blood pressure. We conclude that soluble guanylyl cyclase subunit loci, ie, alpha1, beta1, and beta2, are good candidates for genes controlling salt-sensitive hypertension in the Dahl rat.     

Intralesional cytokine therapy in cancer: a pilot study of GM-CSF infusion in mesothelioma

Most cases of left ventricular aneurysms undergo operation through resection of the exteriorized dyskinetic area with longitudinal suturing of the opening and this technique has been considered by cardiologists (Froehlich et al) to bring no improvement to the morphology and performance of the left ventricle. Some technical modifications have been adopted, such as the septal plicature (Cooley) or circular suturing of the opening (Jatene). Since 1984 our team has used an endoventricular patch, sutured over the contractile area and excluding the akinetic non-resectable scars, bringing a significant and calculable improvement to the left ventricular function. This technique of left ventricular reconstruction (LVR), called endoventricular circular patch plasty (EVCPP) has been already used on more than 750 patients (May 97). Clinical and echographic data for each case are completed by right catheterisation with measurement of the cardiac output, pulmonary arterial pressures (PAP) and programmed ventricular stimulation (PVS), in order to detect eventual ventricular tachycardia (IVT). During left heart catheterisation, the morphology of the left ventricle (LV) is studied on right and left anterior oblique incidences and the LV ejection fraction (EF) is checked globally (GEF) and especially in its contractile portion (CEF). After surgery, a hemodynamic study associated with a PVS, is carried out during the first post-operative month, and again after one year. Results were clinically satisfactory in more than 90% of cases (8.9% of NYHA III-IV), and in more than 90% of cases with ventricular arrhythmia with the hemodynamic persistent EF at one year, superior to the pre-operative CEF. Thus we have to propose the following indications: Elective: This ventricular reconstruction can be recommended for ventricular aneurysms or akinesias with angina, arrhythmias or attacks of cardiac insufficiency, when GEF > 30% and CEF > 40%. The operative mortality rate varies from 1,5 to 3%, which is better than allowing natural evolution. Mandatory: In emergency, when safe immediate circulatory assistance or a cardiac transplant is unavailable, LVR can give hope for survival to more than 80% of patients, whereas natural evolution is without hope. Finally the operative indication is uncertain in two contrasting circumstances: In asymptomatic patients when hemodynamic and angiographic examinations after myocardial infarction show left ventricular dyskinesia. If GEF is below 40% and CEF below 50%, it seems wise to propose LVR in order to prevent unfavourable evolution. In end-stage ischemic cardiomyopathies, if the EF is below 20%, CEF is below 30%, cardiac output is below 1.5 l, and the mean pulmonary pressure is above 25, then a cardiac transplant should be considered. EVCPP with septal exclusion is a safe technique and easily reproduced when associated with coronary revascularization as far as practicable, then EVCPP improves the ventricular function. When associated with sub-total endocardectomy, then EVCPP allows excellent control of VA.