Proteome analysis and genome-wide regulatory motif prediction identify novel potentially sex-hormone regulated proteins in rat efferent ducts.

The efferent ducts are a series of tubules that conduct sperm from the rete testis to the epididymis. They absorb most fluid and proteins originating from the rete testis during concentration of spermatozoa prior to their entry into the epididymis. Proteome analysis of micro-dissected efferent duct samples from adult rats was combined with genome-wide computational prediction of conserved hormone response elements to identify factors likely regulated by oestrogens and androgens. We identified 165 proteins and found subsets of the promoters controlling their corresponding genes to contain androgen- and oestrogen response elements (ARE/EREs) at similar frequencies. Moreover, EREs were significantly enriched among the loci identified compared with their genome-wide occurrence. The expression and localization of Anxa6, Ckb, Krt19, Park7, Pdzk1 and Tpt1 in the efferent ducts and other related hormone controlled tissues was further validated at the RNA or protein level. This study identifies many novel proteins predicted to play roles in sperm maturation and male fertility and provides significant computational evidence that the efferent ducts express genes transcriptionally controlled by sex hormones.

Alkaline single-cell gel electrophoresis (comet assay): a simple technique to show genomic instability in sporadic breast cancer.

The alkaline comet assay was used to study the genomic instability of lymphocytes derived from untreated sporadic breast cancer patients (50 cases), and also following their in vitro irradiation up to 5 Gy. We compared the results (mean tail moment (MTM)) with a control population of 25 patients and with breast cancer patients who had been 'cured' of their disease, with a follow-up of 10 years or more (25 cases). At the basal level, 77.5% (P<0.01) of the untreated patients and 73.7% (P<0.05) of the 'cured' women had values higher than the basal cut-off level of 5.3, compared with only 44% of the controls. After in vitro irradiation, 83% of the untreated patients were above the cut-off value of 10.8 at the 5-Gy dose compared with only 48% of the controls (P<0.01). These results support the hypothesis that women affected by sporadic breast cancer have a constitutional genomic instability. The assessment of the prognostic value of this test could be of interest, particularly in women without axillary nodal involvement.

Genomic instability and breast cancer.

The loss of genomic stability is accepted as being one of the most important aspects of cancer. The correlation between genomic instability and cancer proneness in cases of known genetic syndromes (e.g. ataxia telengectasia, Fanconi anemia) is well established. This study was conducted to assess genomic instability in 19 patients with sporadic breast cancer. We used the comet assay on the lymphocytes of patients before radiotherapy and/or chemotherapy. The alkaline comet assay (single-cell gel electrophoresis) is a sensitive and rapid method for detecting DNA damage (single strand breaks and alkali-labile sites) in G(0) cells, at a single-cell level. This assay was achieved in vitro without irradiation and after exposure (dose ranging from 50 cGy to 5 Gy). The results show that the patients have higher baseline values than controls. At 2 Gy, the mean tail moment, score and the percentage of DNA in the tail increase for both groups but these values are much higher for patients. Our results show that the lymphocyte DNA of cancer patients is more damaged than that of controls with or without irradiation. Our hypothesis is that this baseline DNA damage reflect a genomic instability in sporadic breast cancer. This instability seems to increase after in vitro irradiation.

Radiation effect on rat Sertoli cell function in vitro and in vivo.

PURPOSE: To investigate the response of Sertoli cell function to 60Co gamma-rays. MATERIALS AND METHODS: Rat Sertoli cells were exposed in vitro and in vivo to 60Co gamma-rays in the dose range 3 Gy to 48 Gy and at 3 Gy and 6 Gy respectively. Cell viability and transferrin and IL-6 production were measured at different times following irradiation. RESULTS: This study confirms the resistance of in vitro irradiated rat Sertoli cells in the dose range 3 Gy to 48 Gy in terms of cell number. Radiation had no effect on the IL-1 activity of Sertoli cells. However, the experiments show that despite the absence of a macroscopic effect, Sertoli cells respond to ionizing radiation by increasing transferrin secretion, transferrin response to (Bu)2cAMP stimulation and IL-6 activity. CONCLUSIONS: Transferrin is involved in the transport of iron into germ cells and in cell differentiation. IL-6 is a potent inhibitor of meiotic DNA synthesis. Radio-induced transferrin and IL-6 could play a role in the protection of germ cells and could explain, in part, the resistance of Sertoli cells to radiation.

Exposition of humans to low doses and low dose rate irradiation: an urgent need for new markers and new models.

In human radiation protection, the shape of the dose effects curve for low doses irradiation (LDI) is assumed to be linear, extrapolated from the clinical consequences of Hiroshima and Nagasaki nuclear explosions. This extrapolation probably overestimates the risk below 200 mSv. In many circumstances, the living species and cells can develop some mechanisms of adaptation. Classical epidemiological studies will not be able to answer the question and there is a need to assess more sensitive biological markers of the effects of LDI. The researches should be focused on DNA effects (strand breaks), radioinduced expression of new genes and proteins involved in the response to oxidative stress and DNA repair mechanisms. New experimental biomolecular techniques should be developed in parallel with more conventional ones. Such studies would permit to assess new biological markers of radiosensitivity, which could be of great interest in radiation protection and radio-oncology.

Regional differences in porcine adipocytes isolated from skeletal muscle and adipose tissues as identified by a proteomic approach.

The content and distribution of body lipids are of special interest for production efficiency and meat quality in the farm animal industry. Triglycerides represent the most variable fraction of tissue lipids, and are mainly stored in adipocytes. Although several studies have reported regional differences in the expression of genes and their products in adipocytes from various species, the characteristics of i.m. adipocytes remain poorly described. To evaluate adipocyte features according to muscle and other fat locations, adipocyte proteins were isolated from trapezius skeletal muscle, and intermuscular, s.c., or perirenal adipose tissues from 6 female pigs (80 d of age). Protein extracts were labeled and analyzed by 2-dimensional, fluorescent, differential gel electrophoresis. The comparisons revealed that 149 spots were always differentially expressed (P < 0.05, ratio exceeding |2|-fold difference) between i.m. adipocytes and the fat cells derived from the 3 other adipose locations. The proteins that were downregulated in i.m. fat cells belonged to various metabolic pathways, such as lipogenesis (cytosolic malate dehydrogenase and isocitrate dehydrogenase, P < 0.01), glycolysis (enolases and aldolase, P

[Acari in housedust of the Brazilian capitals and Fernando de Noronha Island]. / Acaros em poeira domiciliar das capitais brasileiras e ilha Fernando de Noronha.

This paper deals with the geographical distribution of astigmatid mites related to human allergy and found in house dust samples collected in all states capitals in Brazil. Definitions and keys for the identification of the species of mites are presented.

[Ectoparasites of rodents and marsupials in the wild environment of Ilha Grande, State of Rio de Janeiro, Brazil]. / Ectoparasitos de roedores e marsupiais no ambiente silvestre de Ilha Grande, Estado do Rio de Janeiro, Brasil.

Ectoparasites collected from wild mammals of Ilha Grande, state of Rio de Janeiro, Brazil, are listed. The most frequent species of mammal was Proechimys dimidiatus (Gunther, 1877); Gigantolaelaps oudemansi Fonseca, 1939 and Polygenis lakoi Guimarães, 1948 were the predominant species of acari and fleas, respectively.

IL-6 a key cytokine in in vitro and in vivo response of Sertoli cells to external gamma irradiation.

Interleukin 1(IL-1) and IL-6 are cytokines involved in the response to radiation and are known for their radioprotective properties with respect to total-body irradiation. We previously showed that after gamma irradiation of Sertoli cells (SC), we observed an increase in the activity of IL-6 but not of IL-1. The aim of this study was to see whether this response is a function of the differentiation of SC, to analyse the mechanisms responsible for this induction, and to test whether this cytokine has a radioprotective role on germ cells. Unlike IL-1, a dose-dependent increase of IL-6 activity in SC following gamma irradiation at high doses was observed at all ages studied. On the other hand, radio-induction observed at low doses (<1Gy) was dose-independent. IL-6 up-regulation resulted from transcriptional activation as shown by the use of specific inhibitors. The injection of IL-1 and IL-6 in mice prior to whole-body irradiation resulted in an increased survival rate. Moreover, cytokines protected DNA from remaining cells following irradiation as shown by comet assay on germ cells. In conclusion, IL-6 seems to constitute a good marker of exposure to gamma irradiation, both at low and high doses. In addition, we showed that IL-1 and IL-6 have a radioprotective effect at testicular level.

Regulatory influence of germ cells on sertoli cell function in the pre-pubertal rat after acute irradiation of the testis.

While germ cell regulation of Sertoli cells has been extensively explored in adult rats in vivo, in contrast, very little is known about germ cell influence on Sertoli cell function at the time when spermatogenesis begins and develops. In the present study various Sertoli cell parameters (number, testicular androgen binding protein (ABP) and testin, serum inhibin-B and, indirectly, follicle-stimulating hormone (FSH)) were investigated after the exposure of 19-day-old rats to a low dose of 3 Grays of gamma-rays. Differentiated spermatogonia were the primary testicular targets of the gamma-rays, which resulted in progressive maturation depletion, sequentially and reversibly affecting all germ cell classes. Testicular weight declined to a nadir when pachytene spermatocytes and spermatids were depleted from the seminiferous epithelium and complete or near complete recovery of spermatogenesis and testicular weight was observed at the end of the experiment. Blood levels of FSH and ABP were normal during the first 11 days after irradiation, when spermatogonia and early spermatocytes were depleted. While the number of Sertoli cells was not significantly affected by the irradiation, from days 11-66 after gamma-irradiation, ABP production declined and FSH levels increased when pachytene spermatocytes and spermatids were depleted and the recovery of these parameters was only observed when spermatogenesis was fully restored. Comparison of the pattern of change in serum levels of inhibin-B and testicular levels of testin and of germ cell numbers strongly suggest a relationship between the disappearance of spermatocytes and spermatids from the seminiferous epithelium and the decrease in levels of inhibin-B and increase in levels of testin from 7 to 36 days post-irradiation. Levels of testin and inhibin-B were restored before spermatogenesis had totally returned to normal. In conclusion, this in vivo study shows that pre-pubertal Sertoli cell function is under the complex control of various germ cell classes. This control presents clear differences when compared with that previously observed in adult animals and depends on the Sertoli cell parameter of interest, as well as on the germ cell type.

Fauna Triatominae do Estado de Bahia, Brasil.V - Microtriatoma pratai sp. n. Hemiptera, Reduviidae, Triatominae, Bolboderini. / Triatomidae fauna of the State of Bahia, Brazil. V - Microtriatoma pratai sp. n. - Hemiptera,Reduviidae, Triatominae, Bolderini

Microtriatoma pratai sp. n. de Hemiptera, Reduviidae, Triatominae, Bolboderini, e descrita no presente trabalho com base em um exemplar coletado em domicilio da cidade do Salvador, Estado da Bahia, Brasil. A especie se distingue facilmente das outras conhecidas do genero, principalmente por apresentar asas sem manchas e conexivo com largas manchas claras e escuras alternadas

Observacoes sobre acao do fungo Metarrhizium anisopliae Metschnikoff sobre algumas especies de Triatominae (Hemiptera, Reduviidae). / Observations on action of the fungus Metarrhizium anisopliae Metschnikoff on some species of Triatominae (Hemiptera, Reduviidae)

Esporos do fundo Metarrhizium anisopliae (Metsch) em meio de arroz cozido foram suspensos em agua destilada e aspergidos sobre ninfas e adultos de Triatoma infestans, Panstrongylus megistus, Triatoma brasiliensis e Rhodnius neglectus. Durante seis meses de observacoes, apenas dois exemplares se mostraram discretamente infectados pelo fungo. A mortalidade dos triatomineos testes foi semelhante a dos controles. Esporos de M. anisopliae no proprio meio de cultura foram mantidos junto a exemplares de T. infestans e T. brasiliensis em fases de ninfas e adultos.Apos 20 dias iniciou-se a mortalidade dos triatomineos testes, 80% dos quais se apresentaram altamente infectados pelo fungo, enquanto que nos controles nada de anormal se verificou. Exemplares mortos de T. infestans altamente infectados na experiencia anterior, foram colocados junto a exemplares sadios de T. infestans e T. brasiliensis, mantendo-se outro grupo para controle. Vinte dias apos, iniciou-se a mortalidade dos triatomineos, mostrando-se a maioria infectada pelo fungo.Concluiu-se que M. anisopliae quando utilizado em suspensao aquosa apresenta baixa infectividade para os triatomineos. Entretanto, quando utilizado em culturas puras, e altamente infectante, demonstrando possuir tambem acao letal para esse reduvideo