Parasite × vector relationship in Chagas disease: does Trypanosoma cruzi (Chagas, 1909) infection affect the spermatogenesis of Triatoma infestans (Klug, 1834)?

The parasite-vector interaction of Chagas disease is still poorly understood and the understanding of this relationship can help in the development of new strategies to control Trypanosoma cruzi transmission, which is the etiological agent of this disease. Considering the need to know if T. cruzi can cause some pathology in the reproductive system of the Chagas disease vectors, we investigated the spermatogenesis of Triatoma infestans infected by T.

[Cancer screening programme in health care workers].

From the 2002 through 2009 years 419 health care workers of the Hospital of Lecco, occupationally exposed to X-ray, were invited to undergo a cancer screening programme for the early diagnosis of cervical, breast, colorectal and prostate cancers. A total of 341 subjects performed the screening tests with an overall compliance of 83,8%; the participation rate to each test was significantly higher than that of general population. Breast cancer was diagnosed and treated in 5 women, cervical premalignant lesions in 8 women and colorectal adenomas in 13 subjects; no prostate cancer was detected.

Role of the mismatch repair system and p53 in the clastogenicity and cytotoxicity induced by bleomycin.

The mismatch repair (MMR) system and p53 protein play a pivotal role in maintaining genomic stability and modulate cell chemosensitivity. Aim of this study was to examine the effects of either MMR-deficiency or p53 inactivation, or both, on cellular responses to bleomycin. The MMR-deficient colon carcinoma cell line HCT116 and its MMR-proficient subline HCT116/3-6, both expressing wild-type p53, were transfected with an expression vector encoding a dominant-negative p53 mutant, or with the empty vector.

Individual susceptibility to DNA telomerase inhibitors: a study on the chromosome instability induced by 3'-azido-3'-deoxythymidine in lymphocytes of elderly twins.

The activation of telomerase in phytohemagglutinin-stimulated peripheral lymphocytes is thought to play a role in telomere maintenance and DNA repair. Considering the importance of this enzyme in both cancer and senescence, we studied the effects of the telomerase inhibitor 3'-azido-3'-deoxythymidine on the frequency of chromosomal aberrations and micronuclei induced in peripheral blood lymphocytes (PBL) of elderly monozygotic and dizygotic twins, evaluated with respect to the genotoxic effects induced in unrelated young subjects. Our results show that the cytogenetic damage induced by 3'-azido-3'-deoxythymidine in human PBL was mainly regulated by genetic factors and allowed the identification of hypersensitive subjects.

Aphidicolin and bleomycin induced chromosome damage as biomarker of mutagen sensitivity: a twin study.

The induction of chromosome damage in cultured human lymphocytes by in vitro treatments with aphidicolin (APC) and bleomycin (BLM) has been proposed as test of sensitivity to mutagens. To assess their validity, we have investigated whether the individual expression of induced chromosome damage has a genetic rather than an environmental basis. Metaphase analysis for chromosomal aberrations (CA) and micronucleus (MN) assay in cytokinesis-blocked cells have been performed in peripheral blood lymphocytes from 19 healthy male twins (9 monozygotic and 10 dizygotic pairs), aged 70-78 years, after APC, BLM and APC+BLM treatments.

Three subpopulations of fast axonally transported retinal ganglion cell proteins are differentially trafficked in the rat optic pathway.

Post-Golgi trafficking of the major fast axonally transported (FT) proteins was investigated in the rat optic pathway. Following intra-ocular injection of 35S-methionine, radiolabeled FT proteins in the optic tract (OT) and superior colliculus (SC) were analyzed by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and fluorography. Twenty FT proteins, including a known plasma membrane protein (SNAP-25) and synaptic vesicle protein (synaptobrevin-2), displayed consistent 2D-PAGE migration behavior and were chosen for densitometric quantitative analysis.

Bleomycin-induced chromosome aberrations in lymphocytes derived from patients with lamellar ichthyosis.

Patients affected by some genetic skin defects, for example, dyskeratosis congenita or scleroderma, may present spontaneous or induced chromosomal fragility. Hence we performed a cytogenetic analysis in families of patients affected by lamellar ichthyosis, an autosomal recessive disease not yet fully characterized at the cellular and molecular levels. Chromosomal fragility was assayed in untreated lymphocyte cultures and in those supplemented with aphidicolin or bleomycin.

A new case of Ambras syndrome associated with a paracentric inversion (8) (q12; q22).

Ambras syndrome (AS) is a special form of congenital universal hypertrichosis described for the first time by Baumeister et al. (1). This form differs from other forms of congenital hypertrichosis in the pattern of hair distribution and its associated anomalies.

Induction of apoptosis by bleomycin in resting and cycling human lymphocytes.

Bleomycin induces DNA and chromosome breakage. The differential sensitivity to the drug has been used in vitro to identify individuals at high risk of developing tumours. However, there are limited reports on the ability of bleomycin to induce apoptosis.

Sister chromatid exchanges and DNA topoisomerase II inhibitors: effect of low concentrations of etoposide (VP-16) in ataxia telangiectasia lymphoblastoid cell lines.

The correlation between etoposide (VP-16) cytotoxicity and the induction of sister chromatid exchanges (SCEs) suggested that the promotion of DNA recombination events may be crucial for the activity of antitopoisomerase drugs. To further evaluate this hypothesis, we investigated the correlation between VP-16 induction of SCEs, chromosomal aberrations and cell cycle alterations in lymphoblastoid cell lines derived from patients affected by ataxia telangiectasia (AT), whose cells are known as hypersensitive to the cytotoxic and clastogenic activity of DNA topoisomerase II inhibitors. Our present study has shown that AT homozygous and heterozygous cell lines exposed to low VP-16 concentrations, although hypersensitive to the induction of chromosomal aberrations, exhibit an induction of SCEs comparable to that found in normal cell lines.

In vitro effects of growth hormone (GH) and insulin-like growth factor I and II (IGF-I and -II) on chromosome fragility and p53 protein expression in human lymphocytes.

Background: We have reported previously that growth hormone (GH) therapy increases cell radiosensitivity; in this study we tested whether GH itself or IGFs induce chromosome aberrations and investigated the expression of p53 protein in response to DNA damage.

Methods: Human peripheral blood lymphocytes were incubated with GH [100 and 1000 microg L(-1)], insulin-like growth factor I [IGF-I; 150 and 1000 microg L(-1)] and IGF-II [600 and 1200 microg L(-1)] for 24 h. The radiomimetic agent bleomycin [BLM; 5 microgm L(-1)] was added in the last 3 h.

Cytogenetic effects in lymphocytes from children exposed to radiation fall-out after the Chernobyl accident.

In a previous paper we reported that a group of children exposed to ionizing radiation following the Chernobyl accident exhibited an appreciable number of chromosome breaks and rearrangements reflecting the persistence of a radiation-induced damage. The results suggested that the children were still exposed to radioactive contamination through consumer foodstuff and life styles. In the present paper, 31 exposed children have been considered together with a control group of 11 children with the aim to confirm previous results.

Differential effects of axotomy on the in vivo synthesis of the stress-inducible and constitutive 70-kDa heat-shock proteins in rat dorsal root ganglia.

The purpose of this study was to the test the hypothesis that heat-shock protein expression is upregulated (or induced) in dorsal root ganglia (DRG) following axotomy. To test this hypothesis, DRG or sciatic nerve (SN) proteins were pulse-labelled in vivo with [35S]methionine and the metabolic synthesis of two major 70-kDa heat-shock proteins, the constitutive species (hsc70) and stress-inducible species (hsp68), were analyzed by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and fluorography. Results showed that DRG hsp68 expression was absent (or barely detectable) under normal (sham-axotomy) conditions.

T cell priming against vesicular stomatitis virus analyzed in situ: red pulp macrophages, but neither marginal metallophilic nor marginal zone macrophages, are required for priming CD4+ and CD8+ T cells.

Since extensive degradation may be required to present complex Ags, we addressed whether macrophages (M phi) might function as APC for anti-viral cell-mediated immune responses. To study this question, murine splenic M phi were depleted by i.p.

Do human lymphocytes exposed to the fallout of the Chernobyl accident exhibit an adaptive response? III. Challenge with bleomycin in lymphocytes from children hit by the initial acute dose of ionizing radiation.

In the present paper, we report data on the possible adaptive response, induced in vivo by exposure to ionizing radiation to a challenge treatment with the radiomimetic glycopeptide bleomycin (BLM). Lymphocytes from children living in Pripjat at the time of the Chernobyl accident, and thus hit by the initial acute dose of ionizing radiation, were treated for the last 5 h of culture with 0.004 U/ml BLM.

Do human lymphocytes exposed to the fallout of the Chernobyl accident exhibit an adaptive response? 2. Challenge with bleomycin.

The present study concerns the possible adaptive response, induced in vivo by a continuous exposure to ionizing radiations, to a challenge treatment with the radiomimetic glycopeptide bleomycin (BLM). Lymphocytes from children contaminated as a consequence of Chernobyl accident were treated for the last 5 h of culture with 2.5 micrograms/ml BLM.

Do human lymphocytes exposed to the fallout of the Chernobyl accident exhibit an adaptive response? 1. Challenge with ionizing radiation.

Several studies suggest that cells appear to become less susceptible to the induction of radiation damage, and in particular of chromosome and chromatid aberrations in short-term cultures of human lymphocytes, when a challenge exposure to ionizing radiation is preceded by a low 'adaptive' dose. Contradictory results have been reported on the conditions under which the phenomenon can be evidenced. In the present work, circulating lymphocytes of 13 children contaminated from the fallout after the Chernobyl accident were tested for their capability to exhibit an adaptive response in experiments in which the challenge dose was administered to stimulated lymphocytes in the S-G2 phase.

Characteristic chromosomal fragility of human embryonic cells exposed in vitro to aphidicolin.

The frequency and distribution of aphidicolin (APC)-induced common fragile sites (cfs) were analyzed in human embryonic cells of different origins. Embryonic lung fibroblasts (MRC-5), amniocytes (AMINO) and embryonic retina cells (HERO790) are as sensitive to the APC-induced clastogenic effect as peripheral lymphocytes, whereas embryonic kidney cells (HEK) seem more resistant to the induction of chromosomal gaps and breaks by the drug. Analysis of the distribution of fragile sites confirmed that the expression of specific APC-induced cfs varies in different cells and that the embryonic cell strains show a greater similarity among themselves than to lymphocytes.

Complex glycerol kinase deficiency: an unusual cause of salt-wasting in males.

We report the case of a male infant who at 10 days of life presented with salt-wasting. Congenital adrenal hyperplasia was excluded on the basis of normal 17 alpha-hydroxy-progesterone plasma levels evaluated before the onset of steroid replacement therapy. The incidental finding of hypertriglyceridaemia led us to suspect the condition of complex glycerol kinase deficiency which was confirmed by the direct measurement of serum glycerol (7.

Subregional localization of 14 yeast artificial chromosomes to human chromosome region 1p by fluorescence in situ hybridization.

We have sublocalized to the region between 1p22 and 1p33 a total of 14 yeast artificial chromosomes previously assigned to a broader area of human chromosome 1p. Our purpose was to map DNA sequences that could be used for the molecular characterization of the two common fragile sites present in bands 1p31.2 and 1p32, the expression of which is increased in patients with neuroblastomas.

Priming antiviral cytotoxic T lymphocytes: requirement for CD4+ cells is dependent on the antigen presenting cell in vivo.

We have analyzed cytotoxic thymus-derived lymphocyte (CTL) responses to vesicular stomatitis virus (VSV) to determine whether VSV precursor CTL (pCTL) can be primed in vivo in the absence of CD4+ cells. Our studies demonstrated that secondary anti-VSV CTL responses in vitro were markedly reduced by CD4-depletion prior to priming in vivo with VSV. Limiting dilution analysis indicated that the vast majority (> 90%) of VSV pCTL failed to become primed when exposed to VSV in the absence of CD4+ cells.

Heat stress induces hsc70/nuclear topoisomerase I complex formation in vivo: evidence for hsc70-mediated, ATP-independent reactivation in vitro.

We previously demonstrated that in murine T cells thermotolerance correlated with heat shock protein 70 (hsp70) synthesis and protection of nuclear type I topoisomerase (topo I). Topo I activity returned to normal levels following heat stress even in cells not rendered thermotolerant by a prior heat shock. Recovery of topo I activity was not dependent on de novo protein synthesis, suggesting that the cell possesses a pathway(s) for refolding this nuclear protein.

Cytogenetic study in lymphocytes from children exposed to ionizing radiation after the Chernobyl accident.

The present study concerns the monitoring of children from the Byelorussian, Ukrainian and Russian republics exposed to the fall-out of the Chernobyl accident. Cytogenetic analyses have been performed on 41 children coming from different areas and exhibiting varying amounts of 137Cs internal contamination, as evaluated by whole-body counter (WBC) analysis. On a total of 28,670 metaphases scored, radiation-induced chromosome damage is still present, although at a very low frequency.