70 research outputs found

    Neutrophils Suppress Intraluminal NK Cell-Mediated Tumor Cell Clearance and Enhance Extravasation of Disseminated Carcinoma Cells

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    Immune cells promote the initial metastatic dissemination of carcinoma cells from primary tumors. In contrast to their well-studied functions in the initial stages of metastasis, the specific roles of immunocytes in facilitating progression through the critical later steps of the invasion–metastasis cascade remain poorly understood. Here, we define novel functions of neutrophils in promoting intraluminal survival and extravasation at sites of metastatic dissemination. We show that CD11b+/Ly6G+neutrophils enhance metastasis formation via two distinct mechanisms. First, neutrophils inhibit natural killer cell function, which leads to a significant increase in the intraluminal survival time of tumor cells. Thereafter, neutrophils operate to facilitate extravasation of tumor cells through the secretion of IL1β and matrix metalloproteinases. These results identify neutrophils as key regulators of intraluminal survival and extravasation through their cross-talk with host cells and disseminating carcinoma cells. SIGNIFICANCE: This study provides important insights into the systemic contributions of neutrophils to cancer metastasis by identifying how neutrophils facilitate intermediate steps of the invasion–metastasis cascade. We demonstrate that neutrophils suppress natural killer cell activity and increase extravasation of tumor cells.Human Frontier Science Program (Strasbourg, France) (fellowship LT00728/2008-L)Charles King Trust FoundationMassachusetts Institute of Technology. Ludwig Center for Cancer ResearchCancer Research Institute (New York, N.Y.) (Irvington Fellowship)National Institutes of Health (U.S.) (grant P01 CA080111)National Institutes of Health (U.S.) (grant CA163109

    Nutritive value of unconventional fibrous ingredients fed to Guinea pigs in the Democratic Republic of Congo

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    peer reviewedThe energy and protein value for Guinea pigs (GP) of 9 forages (7 dicots and 2 grasses) and 5 hay-based diets was determined. The apparent faecal digestibility of dry matter, organic matter, crude protein and energy was measured on GP housed in metabolic cages. The forages and the diets were digested in vitro using pepsin and pancreatin hydrolysis and gas fermentation test to simulate stomach, small intestine and large intestine, respectively. Most of the dicots had high digestible crude protein content (152–201 g/kg DM) and the 2 grasses showed lower values (80–85 g/kg DM). Digestible energy content of the forages ranged between 5.79 to 13.08 MJ/kg DM. None of the forage species or hay-based diets provided sufficient energy to supply the 11.7 MJ/kg metabolic energy requirements. The influence of intestinal fermentation on energy and protein values was highlighted by correlations (P<0.05) between in vivo and in vitro data, including gas fermentation. It is the first time that such relationships are reported in single-stomach animals

    Choice of lard, but not total lard calories, damps adrenocorticotropin responses to restraint

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    Although rats given the choice of eating high-density calories as concentrated sucrose solutions or lard exhibit reduced responsivity in the hypothalamo-pituitary-adrenal axis, rats fed high-fat diets have normal or augmented responses to stressors. To resolve this apparent discrepancy, we compared in adult male rats the effects of 7-d feeding with lard + chow (choice) to feeding a 50% lard-chow mixture (no-choice) and to chow only. Rats with choice composed diets with 50-60% total calories from lard. Rats were exposed to 30 min of restraint on d 7. In the choice group, there was a robust inhibition of ACTH and corticosterone responses to restraint compared with chow or no-choice groups. Total caloric intake was less with choice than no-choice. Fat depot weights and body weight gain were similar in the high-fat groups. Leptin concentrations were equal but insulin was higher in the choice group. We conclude the following: 1) choice of eating high-density calories strongly damps hypothalamo-pituitary-adrenal responses to stress; without choice, high-density diet is ineffective; and 2) insulin may signal metabolic well-being, and may act through hypothalamic sites to reduce caloric intake but through forebrain sites to damp stress response

    Ruptured endometrioma in a nonpregnant patient: a case report.

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    BackgroundEndometriomas are a type of ovarian cyst composed of degenerated blood products from hemorrhage of ectopic endometrial tissue. Endometriomas can rupture, causing hemoperitoneum, and present with signs and symptoms similar to other, more common abdominal emergencies. Therefore, they are not often diagnosed preoperatively. Ultrasound and cross-sectional imaging can assist in diagnosis of endometriomas. We present a case of ruptured endometrioma causing massive hemoperitoneum that was initially suspected to represent malignancy with carcinomatosis.Case presentationA 32-year-old Hispanic woman presented with sharp abdominal pain and 15-pound unintentional weight loss over 6&nbsp;months. Laboratory work was significant for a negative pregnancy test and elevated cancer antigen-125. Computed tomography of the abdomen and pelvis demonstrated a 13-cm complex cystic mass in the left adnexa with moderate hyperdense ascites and omental nodularity. Ultrasound demonstrated a large left adnexal complex cystic structure with internal echoes, and chest computed tomography showed no signs of intrathoracic neoplastic or infectious processes. Her presentation was concerning for malignancy with carcinomatosis. Fluid from a paracentesis was sent for culture and cytology. Diagnostic laparoscopy revealed that the left ovary had been completely replaced by an endometrioma, which had a small ruptured area superiorly. Brown deposits of endometriosis were present on the cyst, omentum, and various peritoneal linings. Tissue samples of the endometrium, myometrium, cervix, ovaries, fallopian tubes, peritoneum, omentum, and paracolic spaces were taken and showed no hyperplastic, dysplastic, or malignant cells on pathology.ConclusionsRuptured endometrioma and ruptured hemorrhagic cyst should be included in the differential diagnosis when a premenopausal female presents with hemoperitoneum in combination with complex adnexal cystic masses in the absence of trauma. Cancer antigen-125 and cancer antigen 19-9 can be falsely elevated in the setting of ruptured endometrioma

    Hepatic vagotomy alters limbic and hypothalamic neuropeptide responses to insulin-dependent diabetes and voluntary lard ingestion

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    Hypothalamic anorexigenic [corticotropin-releasing factor (CRF) and proopiomelanocortin] peptides decrease and the orexigen, neuropeptide Y, increases with diabetic hyperphagia. However, when diabetic rats are allowed to eat lard (saturated fat) as well as chow, both caloric intake and hypothalamic peptides normalize. These neuropeptide responses to lard require an intact hepatic vagus [la Fleur et al. (2003) Diabetes, 52, 2321-2330]. Here, we delineate temporal interactions after lard consumption +/- hepatic vagotomy (HV) between feeding and brain neuropeptide expression in insulin-dependent diabetic rats. CRF-mRNA was reduced in the paraventricular nuclei (PVN) by 6 h after presentation of lard, before caloric intake increased in HV-diabetic rats, and did not increase at 30 or 36 h, as it did in shamHV-diabetic rats eating lard. CRF-mRNA was increased in the bed nuclei of the stria terminalis of HV-diabetic rats compared with shamHV-diabetic rats only when caloric intake was high at 30 or 36 h. At 36 h, shamHV-diabetic rats eating chow had increased CRF-mRNA in the central amygdala but diabetic rats eating lard had decreased CRF-mRNA, whereas HV-diabetic rats eating chow or lard had normal CRF-mRNA in the central amygdala. We conclude that eating lard restores peptide expression to normal in the hypothalamus of diabetic rats, and because decreased CRF-mRNA in the PVN precedes the increase in caloric intake in HV-diabetic rats eating lard, that the loss of a hepatic vagal signal to PVN may be responsible for increased intake; moreover, CRF-mRNA in limbic structures is also sensitive to both HV and lard ingestion in diabetic rat

    Studies on Aspergillus flavus Link. isolated from maize in Iran

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    The Aspergillus flavus population structure from maize kernels was examined. During 2011, samples were collected from two main grain maize production areas in Iran (Fars and Ardebil provinces), shortly before harvest. One-hundred nine A. flavus isolates were recovered on Dichloran Rose Bengal Chloramphenicole (DRBC) agar and Aspergillus flavus/parasiticus medium (AFPA) and grouped into morphotypes and Vegetative Compatibility Groups (VCGs) based on morphological (e.g. sclerotia production), physiological (e.g. aflatoxin-producing ability) and genetic criteria (e.g. heterokaryosis). In general, morphotype and VCG composition were highly dissimilar in both provinces. In total, 43.8% and 44.3% of A. flavus isolates from Ardebil and Fars, respectively, produced sclerotia. Sclerotia producers were identified as A. flavus L and S strain morphotypes in Ardebil (66.7% and 33.3%, respectively) and Fars (29.6% and 70.4%, respectively). Furthermore, 71 isolates (65.1%) were able to produce aflatoxin (Ardebil 40.8%, Fars 59.2%). The aflatoxin values were categorized into four different classes ( 1,000 ppb). In total, 51 aflatoxin producing isolates of A. flavus (Ardebil n = 22, Fars n = 29) were assigned into 26 VCGs by complementation of nit auxotrophs on nitrate medium. None of the A. flavus isolates from Ardebil complemented with any isolates from Fars. Genetic diversity of A. flavus isolates was 59.1% and 41.8% for Ardebil and Fars, respectively. The different geographical adaptation and genetic make-up of A. flavus isolates may be due to different climatic conditions, soil types and crop sequences in both maize production areas

    Minireview: glucocorticoids--food intake, abdominal obesity, and wealthy nations in 2004

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    Glucocorticoids have a major effect on food intake that is underappreciated, although the effects of glucocorticoids on metabolism and abdominal obesity are quite well understood. Physiologically appropriate concentrations of naturally secreted corticosteroids (cortisol in humans, corticosterone in rats) have major stimulatory effects on caloric intake and, in the presence of insulin, preference. We first address the close relationship between glucocorticoids and energy balance under both normal and abnormal conditions. Because excess caloric intake is stored in different fat depots, we also address the systemic effects of glucocorticoids on redistribution of stored energy preponderantly into intraabdominal fat depots. We provide strong evidence that glucocorticoids modify feeding and then discuss the role of insulin on the choice of ingested calories, as well as suggesting some central neural pathways that may be involved in these actions of glucocorticoids and insulin. Finally, we discuss the evolutionary utility of these actions of the stress hormones, and how dysregulatory effects of chronically elevated glucocorticoids may occur in our modern, rich societie
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