293 research outputs found

    Altered operant responding for motor reinforcement and the determination of benchmark doses following perinatal exposure to low-level 2,3,7,8-tetrachlorodibenzo-p-dioxin.

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    Pregnant Holtzman rats were exposed to a single oral dose of 0, 20, 60, or 180 ng/kg 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the 18th day of gestation. Their adult female offspring were trained to respond on a lever for brief opportunities to run in specially designed running wheels. Once they had begun responding on a fixed-ratio 1 (FR1) schedule of reinforcement, the fixed-ratio requirement for lever pressing was increased at five-session intervals to values of FR2, FR5, FR10, FR20, and FR30. We examined vaginal cytology after each behavior session to track estrous cyclicity. Under each of the FR values, perinatal TCDD exposure produced a significant dose-related reduction in the number of earned opportunities to run, the lever response rate, and the total number of revolutions in the wheel. Estrous cyclicity was not affected. Because of the consistent dose-response relationship at all FR values, we used the behavioral data to calculate benchmark doses based on displacements from modeled zero-dose performance of 1% (ED(01)) and 10% (ED(10)), as determined by a quadratic fit to the dose-response function. The mean ED(10) benchmark dose for earned run opportunities was 10.13 ng/kg with a 95% lower bound of 5.77 ng/kg. The corresponding ED(01) was 0.98 ng/kg with a 95% lower bound of 0.83 ng/kg. The mean ED(10) for total wheel revolutions was calculated as 7.32 ng/kg with a 95% lower bound of 5.41 ng/kg. The corresponding ED(01) was 0.71 ng/kg with a 95% lower bound of 0.60. These values should be viewed from the perspective of current human body burdens, whose average value, based on TCDD toxic equivalents, has been calculated as 13 ng/kg

    Autistic Masking

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    This study investigated the relationships between autistic masking and depression, anxiety, gender identity, sexual orientation, social trauma, self-esteem, authenticity, and autistic community involvement. Participants were autistic adults (n=342) recruited through autistic social media groups. The majority of participants (63%) reported being members of sexual minorities. The study found higher self-reported autistic masking behaviors were associated with higher reports of past social trauma (p \u3c .001, b = .26), greater anxiety (p \u3c .001, b = .37) and depression symptoms (p \u3c .001, b = .312), lower self-esteem (p \u3c .001, b = -.25), lower authentic living (p = .005, b = -.16), greater accepting of external influence (p \u3c .001, b= .33), higher self-alienation (p \u3c .001, b = .26), and lower participation within the autistic community (p \u3c .001, b = -.19). Autistic masking was not found to be associated with gender identity or sexual orientation. Participants who reported involvement in previous ABA therapy reported higher past social trauma than participants involved in some other forms of therapy such as cognitive behavior therapy

    The effects of salinity and temperature on the development and survival of fish parasites

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    In brackish water the variety of marine and freshwater parasite species is considerably reduced. The distribution in brackish water of most marine endoparasites is restricted by the salinity tolerance of their hosts, most of the parasite species are more tolerant than their hosts. The influence of salinity and temperature on nine species has been examined; first stage larvae of Contracaecum aduncum develop in 0-32‰ salinity; Cryptocotyle lingua proved to be infective at salinities down to 4‰. The greatest resistance was found in Anisakis larvae from herring Clupea harengus, which survived for more than half a year. Parasites in the fish intestines appear to be unaffected by changing water salinities, as the osmolarity in the intestines stays nearly constant. Marine ectoparasites (Acanthochondria depressa, Lepeophtheirus pectoralis) survive about three times longer than freshwater species (Piscicola geometra, Argulus foliaceus) when salinity is 16‰. High temperature increases the effects of adverse salinities on parasites. There is evidence that none of these ecto-parasitic species can develop within the range of 7-20‰ salinity

    Immunohistochemical peculiarities of collagen-synthesis function of the main structural components of the uterus of the fetuses from mothers with complicated pregnancies

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    С целью установления особенностей коллаген-синтезирующей функции основных компонентов матки плодов изучили строение органа у 41 плода. Использовали антропометрический, органометрический, гистологический, гистохимический, иммуногистохимический и статистический методы исследования. Иммуногистохимическим методом установлено нарушение коллагенообразования, что проявляется усилением синтеза коллагенов I и III типов наряду со снижением содержания коллагена IV типа в соединительной ткани слоев стенки матки. Описанные изменения могут способствовать развитию несостоятельности стенки матки, проявиться в дальнейшем нарушением репродуктивной функции и быть одним из проявлений дисплазии соединительной ткани у плодов и новорожденных от матерей, беременность которых осложнена преэклампсией различной степени тяжести.З метою виявлення особливостей колаген-синтезуючої функції основних компонентів матки плодів вивчили будову органа 41 плода. Використали антропометричний, органометричний, гістологічний, гістохімічний, імуногістохімічний і статистичний методи дослідження. Імуногістохімічним методом встановили порушення колагеноутворення, що проявляється посиленням синтезу колагенів I і III типів поряд зі зниженням вмісту колагену IV типу в сполучній тканині шарів стінки матки. Ці зміни можуть призводити до розвитку функціональної недостатності стінки матки, надалі проявитися порушенням репродуктивної функції та бути одним із проявів дисплазії сполучної тканини у плодів і новонароджених від матерів, вагітність яких ускладнена преклампсією різного ступеня тяжкості.Aim. To identify features of collagen-synthesizing function of the main components of the uterus of the fetuses. Methods and results. 41 fetuses body structure were studied. Anthropometric, organometric, histological, histochemical, immunohistochemical and statistical methods were used. Immunohistochemistry results found a violation of collagen synthesis. Collagen types I and III production was increased and collagen type IV – decreased. Conclusion. This connective tissue peculiarities in uterus wall layers may contribute to the development of the tissue dysplasia and reproductive dysfunction in the future

    Microarray Analysis Reveals Distinct Gene Expression Profiles Among Different Tumor Histology, Stage and Disease Outcomes in Endometrial Adenocarcinoma

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    Endometrial cancer is the most common gynecologic malignancy in developed countries and little is known about the underlying mechanism of stage and disease outcomes. The goal of this study was to identify differentially expressed genes (DEG) between late vs. early stage endometrioid adenocarcinoma (EAC) and uterine serous carcinoma (USC), as well as between disease outcomes in each of the two histological subtypes.Gene expression profiles of 20 cancer samples were analyzed (EAC = 10, USC = 10) using the human genome wide illumina bead microarrays. There was little overlap in the DEG sets between late vs. early stages in EAC and USC, and there was an insignificant overlap in DEG sets between good and poor prognosis in EAC and USC. Remarkably, there was no overlap between the stage-derived DEGs and the prognosis-derived DEGs for each of the two histological subtypes. Further functional annotation of differentially expressed genes showed that the composition of enriched function terms were different among different DEG sets. Gene expression differences for selected genes of various stages and outcomes were confirmed by qRT-PCR with a high validation rate.This data, although preliminary, suggests that there might be involvement of distinct groups of genes in tumor progression (late vs. early stage) in each of the EAC and USC. It also suggests that these genes are different from those involved in tumor outcome (good vs. poor prognosis). These involved genes, once clinically verified, may be important for predicting tumor progression and tumor outcome

    ETS Transcription Factors Control Transcription of EZH2 and Epigenetic Silencing of the Tumor Suppressor Gene Nkx3.1 in Prostate Cancer

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    ETS transcription factors regulate important signaling pathways involved in cell differentiation and development in many tissues and have emerged as important players in prostate cancer. However, the biological impact of ETS factors in prostate tumorigenesis is still debated.We performed an analysis of the ETS gene family using microarray data and real-time PCR in normal and tumor tissues along with functional studies in normal and cancer cell lines to understand the impact in prostate tumorigenesis and identify key targets of these transcription factors. We found frequent dysregulation of ETS genes with oncogenic (i.e., ERG and ESE1) and tumor suppressor (i.e., ESE3) properties in prostate tumors compared to normal prostate. Tumor subgroups (i.e., ERG(high), ESE1(high), ESE3(low) and NoETS tumors) were identified on the basis of their ETS expression status and showed distinct transcriptional and biological features. ERG(high) and ESE3(low) tumors had the most robust gene signatures with both distinct and overlapping features. Integrating genomic data with functional studies in multiple cell lines, we demonstrated that ERG and ESE3 controlled in opposite direction transcription of the Polycomb Group protein EZH2, a key gene in development, differentiation, stem cell biology and tumorigenesis. We further demonstrated that the prostate-specific tumor suppressor gene Nkx3.1 was controlled by ERG and ESE3 both directly and through induction of EZH2.These findings provide new insights into the role of the ETS transcriptional network in prostate tumorigenesis and uncover previously unrecognized links between aberrant expression of ETS factors, deregulation of epigenetic effectors and silencing of tumor suppressor genes. The link between aberrant ETS activity and epigenetic gene silencing may be relevant for the clinical management of prostate cancer and design of new therapeutic strategies

    Early Treatment with Fumagillin, an Inhibitor of Methionine Aminopeptidase-2, Prevents Pulmonary Hypertension in Monocrotaline-Injured Rats

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    Pulmonary Hypertension (PH) is a pathophysiologic condition characterized by hypoxemia and right ventricular strain. Proliferation of fibroblasts, smooth muscle cells, and endothelial cells is central to the pathology of PH in animal models and in humans. Methionine aminopeptidase-2 (MetAP2) regulates proliferation in a variety of cell types including endothelial cells, smooth muscle cells, and fibroblasts. MetAP2 is inhibited irreversibly by the angiogenesis inhibitor fumagillin. We have previously found that inhibition of MetAP2 with fumagillin in bleomycin-injured mice decreased pulmonary fibrosis by selectively decreasing the proliferation of lung myofibroblasts. In this study, we investigated the role of fumagillin as a potential therapy in experimental PH. In vivo, treatment of rats with fumagillin early after monocrotaline injury prevented PH and right ventricular remodeling by decreasing the thickness of the medial layer of the pulmonary arteries. Treatment with fumagillin beginning two weeks after monocrotaline injury did not prevent PH but was associated with decreased right ventricular mass and decreased cardiomyocyte hypertrophy, suggesting a direct effect of fumagillin on right ventricular remodeling. Incubation of rat pulmonary artery smooth muscle cells (RPASMC) with fumagillin and MetAP2-targeting siRNA inhibited proliferation of RPASMC in vitro. Platelet-derived growth factor, a growth factor that is important in the pathogenesis of PH and stimulates proliferation of fibroblasts and smooth muscle cells, strongly increased expression of MetP2. By immunohistochemistry, we found that MetAP2 was expressed in the lesions of human pulmonary arterial hypertension. We propose that fumagillin may be an effective adjunctive therapy for treating PH in patients

    Clonal Structure of Rapid-Onset MDV-Driven CD4+ Lymphomas and Responding CD8+ T Cells

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    Lymphoid oncogenesis is a life threatening complication associated with a number of persistent viral infections (e.g. EBV and HTLV-1 in humans). With many of these infections it is difficult to study their natural history and the dynamics of tumor formation. Marek's Disease Virus (MDV) is a prevalent α-herpesvirus of poultry, inducing CD4+ TCRαβ+ T cell tumors in susceptible hosts. The high penetrance and temporal predictability of tumor induction raises issues related to the clonal structure of these lymphomas. Similarly, the clonality of responding CD8 T cells that infiltrate the tumor sites is unknown. Using TCRβ repertoire analysis tools, we demonstrated that MDV driven CD4+ T cell tumors were dominated by one to three large clones within an oligoclonal framework of smaller clones of CD4+ T cells. Individual birds had multiple tumor sites, some the result of metastasis (i.e. shared dominant clones) and others derived from distinct clones of transformed cells. The smaller oligoclonal CD4+ cells may represent an anti-tumor response, although on one occasion a low frequency clone was transformed and expanded after culture. Metastatic tumor clones were detected in the blood early during infection and dominated the circulating T cell repertoire, leading to MDV associated immune suppression. We also demonstrated that the tumor-infiltrating CD8+ T cell response was dominated by large oligoclonal expansions containing both “public” and “private” CDR3 sequences. The frequency of CD8+ T cell CDR3 sequences suggests initial stimulation during the early phases of infection. Collectively, our results indicate that MDV driven tumors are dominated by a highly restricted number of CD4+ clones. Moreover, the responding CD8+ T cell infiltrate is oligoclonal indicating recognition of a limited number of MDV antigens. These studies improve our understanding of the biology of MDV, an important poultry pathogen and a natural infection model of virus-induced tumor formation
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