[D-Leu]MC-LR Has Lower PP1 Inhibitory Capability and Greater Toxic Potency than MC-LR in Animal and Plant Tissues.

Two microcystins, MC-LR and [D-Leu]MC-LR, present in La Plata Basin blooms, are differentiated by substitution of D-Alanine for D-Leucine at position 1. Our objective was to evaluate acute toxicity of [D-Leu]MC-LR and MC-LR in mice (N:NIH Swiss) and beans (). We observed variations in [D-Leu]MC-LR lethal doses with respect to those reported for MC-LR (100 μg/kg), with an increased liver/body weight ratio and intrahepatic hemorrhages in mice exposed to 50-200 μg [D-Leu]MC-LR/kg and slight steatosis after a single 25 μg [D-Leu]MC-LR/kg i.

Hepatic and intestine alterations in mice after prolonged exposure to low oral doses of Microcystin-LR.

Oral intake of Microcystin-LR (MC-LR) is the principal route of exposure to this toxin, with prolonged exposure leading to liver damage of unspecific symptomatology. The aim of the present paper was therefore to investigate the liver and intestine damage generated by prolonged oral exposure to low MC-LR doses (50 and 100 μg MC-LR/kg body weight, administrated every 48 h during a month) in a murine model. We found alterations in TBARS, SOD activity and glutathione content in liver and intestine of mice exposed to both doses of MC-LR.

Analysis association between mitochondrial genome instability and xenobiotic metabolizing genes in human breast cancer.

The aim of this study was to determine the existence of association between the genetic polymorphisms of metabolizing genes GSTM-1, GSTT-1, and NAT-2, and the presence of mitochondrial genome instability (mtGI) in breast cancer cases. Ninety-four pairs of tumoral/nontumoral breast cancer samples were analyzed. Our samples showed 40.

Breast implants as a preventive factor.

After a large number of patients with silicone breast implants worldwide had been evaluated [2, 9], it was concluded that such implants were not carcinogenic. This allowed for experimentation with rats to determine the benefits and potential risks associated with implants. By means of a high-precision monitor, temperature measurements were obtained from 100 silicone-implanted rats.

The potential role of dynamic thermal analysis in breast cancer detection.

Background: It is presently well accepted that the breast exhibits a circadian rhythm reflective of its physiology. There is increasing evidence that rhythms associated with malignant cells proliferation are largely non-circadian. Cancer development appears to generate its own thermal signatures and the complexity of these signatures may be a reflection of its degree of development.

[A simple method to detect disaccharides deficiency].

A simple method, easy to perform during an endoscopic procedure, fast and inexpensive, that allows detecting deficiencies in lactase, sucrase or maltase activities is presented. Briefly, method consists in placing a duodenal biopsy sample in an adequate vial containing lactose, sucrose or maltose solution during a few minutes, and then, adding a few drops of a glucose reactive from commercial origin. Presence of any enzymatic activity is demonstrated when released glucose from any of the disaccharides chosen reacts with the second reactive, turning solution to a red colour.

The p53 codon 72 genotypes in HPV infection and cervical disease.

Objective: [corrected] An experimental study has indicated that individuals homozygous for the Arg-encoding allele of p53 gene may have an increased susceptibility to HPV-related cervical cancer but many epidemiological studies have failed to repeat this result. Many epidemiological studies have failed in the attempt to repeat this results. The aim of the present work was to investigate whether the p53 arginine allele confers a risk factor for cervical carcinogenesis.

Are mammography and palpation sufficient for breast cancer screening? A dissenting opinion.

Breast cancer is an equal opportunity killer in that as many as 60%-70% of breast cancer patients have no obvious risk factor(s). Thus, the continued reliance on the importance of risk factors to initiate screening programs may inhibit further inquiry into better diagnostic and prognostic indicators. An extensive review of past and recent literature reveals that mammography is not an objective examination.

Circadian rhythm chaos: a new breast cancer marker.

The most disappointing aspect of breast cancer treatment as a public health issue has been the failure of screening to improve mortality figures. Since treatment of late-stage cancer has indeed advanced, mortality can only be decreased by improving the rate of early diagnosis. From the mid-1950s to the mid-1970s, it was expected that thermography would hold the key to breast cancer detection, as surface temperature increases overlying malignant tumors had been demonstrated by thermographic imaging.

Presence of heat shock protein in chronic periapical pathology of pulpal origin.

In order to establish whether tissues damaged by Chronic Periapical Pathology (CPP) of endodontic origin produced heat shock protein (HSP) capable of attracting reactive lymphocytes, paraffin sections of samples from the oral cavity of 10 patients with CPP were incubated with commercially available anti-HSP monoclonal antibodies. Antibodies were evidenced employing the alkaline phosphatase immunoenzymatic method (DAKO). HSP was found in the lamina propria infiltrated by lymphocytes, in six of the ten samples.

Demonstration and characterization of HLA-DR positive cells in the stroma of human endometrium.

The proportion of stromal cells expressing DR antigens of the HLA system or reacting with an anti-macrophage antibody was studied by immunohistochemical methods in human proliferative, secretory and post-menopausal endometria. DR+ cells showed a rounded morphology with short expansions and represented 13-25% of the stromal cells in the proliferative and 16-43% in the secretory endometrium. The cells reacting with the anti-macrophage antibody were similar to DR+ cells, but their number was between 1/2 and 1/10 of DR+ cells.

Infection of guinea pigs with two strains of lymphocytic choriomeningitis virus.

In order to study the lesions produced by lymphocytic choriomeningitis virus (LCMV) adult guinea-pigs were inoculated intraperitoneally with 1000 PFU of the WE or the Armstrong strain of LCMV. The animals were sacrificed at 3, 7, 10 and 14 days p.i.

[Augmentation of the phagocytic activity of monocytes in patients with Darier's disease by the oral administration of retinoic acid].

Other tissue involvement has been described in Darier's disease, eg: susceptibility to infection. In order to know if this susceptibility is due to abnormal phagocytosis and if this can revert by administration of retinoic acid (RA), blood monocyte-derived macrophages, from four individuals with Darier's disease were obtained prior and after administration of RA to determine in them morphological, cytochemical and phagocytic activity changes. It was observed that phagocytosis was diminished and RA administration increased it, without changes in enzyme distribution.

In vivo replication of pathogenic and attenuated strains of Junin virus in different cell populations of lymphatic tissue.

Lymphatic tissue is one of the main sites for replication of Junin virus. To characterize which cells are involved in that replication, the presence of Junin virus in purified populations of macrophages and dendritic cells from the spleens of guinea pigs infected with pathogenic and attenuated strains was investigated by immunofluorescence and intracerebral inoculation into newborn mice. The pathogenic strain was present both in macrophages and in dendritic cells, but the attenuated strain selectively infected dendritic cells.