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991.
Joanna Suliburska Paweł Bogdański Danuta Pupek-Musialik Zbigniew Krejpcio 《Biological trace element research》2011,139(2):137-150
Inadequate minerals intake, as well as disruption of some metabolic processes in which microelements are cofactors, are suggested
to lead to the development of hypertension. The role of minerals in the pathogenesis of hypertension still remains to be explained.
In the present study, we sought to determine associations between serum and hair mineral concentrations and serum lipids and
glucose levels. Forty obese hypertensive subjects with insulin resistance and 40 healthy volunteers were recruited in the
study. Blood pressure, BMI, and insulin resistance were recorded in all subjects. Levels of lipids, glucose, sodium and potassium,
iron, copper, zinc, magnesium, and calcium were assessed in serum. Iron, copper, zinc, magnesium, and calcium were assessed
in hair. Dietary intake of the analyzed minerals was estimated. We found distinctly higher concentrations of serum iron and
serum and hair calcium as well as markedly lower levels of hair zinc in the hypertensive subjects. The study group manifested
also significantly lower daily intake of calcium, magnesium, and iron. We observed a relationship between the concentrations
of iron, zinc, and copper in serum and hair and high and low range of cholesterol, triglycerides, and glucose serum levels
in the studied patients. Moreover, this study demonstrated significant correlation between serum and hair concentrations of
selected minerals and their dietary intake and levels of serum lipids and glucose and blood pressure in the study and the
control groups. The obtained results seem to indicate the association between lipid and glucose metabolism and iron, copper,
zinc, and calcium concentrations in blood and hair of hypertensive and obese patients with insulin resistance. 相似文献
992.
Hexacanalis Perrenoud, 1931 was erected for H. abruptus (Southwell, 1911) Perrenoud, 1931 based on the presence of six excretory vessels, a unique feature among the Lecanicephalidea.
The genus has since been considered a junior synonym of Cephalobothrium Shipley & Hornell, 1906 or Lecanicephalum Linton, 1890, or as a genus inquirendum. Based on examination of the syntype series of H. abruptus, this species is redescribed and a lectotype designated. Examination of cestodes from the zonetail butterfly ray Gymnura zonura (Bleeker) from off Indonesian Borneo resulted in the discovery of a second species. Hexacanalis folifer n. sp. is unique among lecanicephalideans in its possession of an ovary that is U-shaped in cross-section and craspedote
proglottids with prominent posterior dorso-ventral processes in the form of large lappets. The presence of six excretory vessels,
confirmed in both species, supports the validity of Hexacanalis. An additional species, H. pteroplateae (Zaidi & Khan, 1976) n. comb., also from a butterfly ray, G. micrura (Bloch & Schneider) [as Pteroplatea micrura (Bloch & Schneider)], is transferred to this genus from Cephalobothrium Shipley & Hornell, 1906. A revised diagnosis of Hexacanalis is presented. Seven species of this genus remain species inquirendae. Hexacanalis appears to parasitise species of the Gymnuridae van Hasselt; however, specific identifications of the hosts are in need of
re-evaluation. A summary of the cestode parasites of the Gymnuridae is presented. 相似文献
993.
994.
There is now evidence that depression, as characterized by melancholic symptoms, anxiety, and fatigue and somatic (F&S) symptoms, is the clinical expression of peripheral cell-mediated activation, inflammation and induction of oxidative and nitrosative stress (IO&NS) pathways and of central microglial activation, decreased neurogenesis and increased apoptosis. This review gives an explanation for the multiple "co-morbidities" between depression and a large variety of a) brain disorders related to neurodegeneration, e.g. Alzheimer's, Parkinson's and Huntington's disease, multiple sclerosis and stroke; b) medical disorders, such as cardiovascular disorder, chronic fatigue syndrome, chronic obstructive pulmonary disease, rheumatoid arthritis, psoriasis, systemic lupus erythematosus, inflammatory bowel disease, irritable bowel syndrome, leaky gut, diabetes type 1 and 2, obesity and the metabolic syndrome, and HIV infection; and c) conditions, such as hemodialysis, interferon-α-based immunotherapy, the postnatal period and psychosocial stressors. The common denominator of all those disorders/conditions is the presence of microglial activation and/or activation of peripheral IO&NS pathways. There is evidence that shared peripheral and / or central IO&NS pathways underpin the pathophysiology of depression and the previously mentioned disorders and that activation of these IO&NS pathways contributes to shared risk. The IO&NS pathways function as a smoke sensor that detect threats in the peripheral and central parts of the body and signal these threats as melancholic, anxiety, and fatigue and somatic (F&S) symptoms. The presence of concomitant depression is strongly associated with a lower quality of life and increased morbidity and mortality in medical disorders. This may be explained since depression contributes to increased (neuro)inflammatory burden and may therefore drive the inflammatory and degenerative progression. It is concluded that the activation of peripheral and / or central IO&NS pathways may explain the co-occurrence of depression with the above disorders. This shows that depression belongs to the spectrum of inflammatory and degenerative disorders. 相似文献
995.
Cain KE Rich MS Ainsworth K Ketterson ED 《Ethology : formerly Zeitschrift fur Tierpsychologie》2011,117(9):786-795
Different forms of aggression have traditionally been treated separately according to function or context (e.g. aggression towards a conspecific versus a predator). However, recent work on individual consistency in behavior predicts that different forms of aggression may be correlated across contexts, suggesting a lack of independence. For nesting birds, aggression towards both conspecifics and nest predators can affect reproductive success, yet the relationship between these behaviors, especially in females, is not known. Here we examine free-living female dark-eyed juncos (Junco hyemalis) and compare their aggressive responses towards three types of simulated intruders near the nest: a same-sex conspecific, an opposite-sex conspecific, and a nest predator. We also examine differences in the strength of response that might relate to the immediacy of the perceived threat the intruder poses for the female or her offspring. We found greater aggression directed towards a predator than a same-sex intruder, and towards a same-sex than an opposite-sex intruder, consistent with a predator being a more immediate threat than a same-sex intruder, followed by an opposite-sex intruder. We also found positive relationships across individuals between responses to a same-sex intruder and a simulated predator, and between responses to a same-sex and an opposite-sex intruder, indicating that individual females are consistent in their relative level of aggression across contexts. If correlated behaviors are mediated by related mechanisms, then different forms of aggression may be expressions of the same behavioral tendency and constrained from evolving independently. 相似文献
996.
Solich J Faron-Gorecka A Kusmider M Palach P Gaska M Dziedzicka-Wasylewska M 《Neurochemistry international》2011,59(2):185-191
The noradrenaline, serotonin and dopamine transporters are three main transporters, which are the target of the antidepressant drugs. In the present study we demonstrate that the life-long deletion of the noradrenaline transporter (NET) induced up-regulation of two other monoamine transporters, dopamine and serotonin (DAT and SERT, respectively). An increase in the binding of [3H]paroxetine to the SERT and [3H]GBR12935 to the DAT was observed in various brain regions of NET-KO mice, without alterations of mRNA encoding these transporters, as measured by in situ hybridization. This important finding impacts the interpretation of previous data indicating the supersensitizity of NET-KO mice for psychostimulants or stronger effect of citalopram in behavioral tests. While using the NET-KO mice in various psychopharmacological studies is very important, one has to be aware that these mice lack NET from the earliest period of their existence, thus compensatory alterations do take place and have to be considered when it comes to interpretation of the obtained results. 相似文献
997.
Polińska B Matowicka-Karna J Kemona H 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2011,49(1):119-124
Ulcerative colitis (colitis ulcerosa) is a non-specific inflammatory bowel disease of unknown etiology. The symptoms which are observed in the course of ulcerative colitis are: an increase in the number of leukocytes and blood platelets, an increase in the concentration of IL-6 and anemia. Blood platelets are the key element, linking the processes of hemostasis, inflammation and the repair of damaged tissues. Activation of blood platelets is connected with changes in their shape and the occurrence of the reaction of release. P-selectin appears on the surfaces of activated blood platelets and the concentration level of soluble P-selectin increases in the blood plasma. The aim of this study was to define whether the increased number of blood platelets in patients with ulcerative colitis accompanies changes in their activation and morphology. A total of 16 subjects with ulcerative colitis and 32 healthy subjects were studied. Mean platelet count, morphological parameters of platelets and MPC were measured using an ADVIA 120 hematology analyzer. Concentrations of sP-selectin and IL-6 in serum were marked by immunoassay (ELISA). MPC, concentration of sP-selectin and IL-6 were significantly higher in subjects with ulcerative colitis compared to those in the healthy group. There was a decrease of MPV in patients with ulcerative colitis, which is statistically significant. Chronic inflammation in patients with ulcerative colitis causes an increase in the number of blood platelets, a change in their morphology and activation. Decreased MPV value reflects activation and the role blood platelets play in the inflammatory process of the mucous membrane of the colon. A high concentration of sP-selectin, which is a marker of blood platelet activation, demonstrates their part in the inflammatory process. The increase in the concentration of sP-selectin correlated positively with the increase in concentration of IL-6. This is why it may be a useful marker of the activity of colitis ulcerosa. 相似文献
998.
Matowicka-Karna J Kralisz M Kemona H 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2011,49(2):280-284
The current study aims to determine the involvement of cellular responses in combating Giardia intestinalis invasion. The study group consisted of 44 women and 18 men, aged 18-72 years, infected with G. intestinalis. The diagnosis was established based on laboratory investigations (examination of stool, choloscopy, GSA-65). Blood for analysis was collected before antiparasitic treatment and two weeks after treatment termination. The control group consisted of 22 women and 18 men aged 20-45 years. The serum concentrations of IL-5, IL-6, IL-13, TNF, IFN-g were assayed using a set of Quantikine human. The concentrations of NO in the serum were determined using a set of Total Nitric Oxide Assay. Patients infected with G. intestinalis showed a statistically significant increase in the levels of NO, IFN-g and IL-13. Even the antiparasitic treatment applied did not reduce the levels of these parameters and only caused a rise in IL-6. Our study showed a lack of acute inflammatory state in the course of G. intestinalis infection. 相似文献
999.
Hayashi AA Webb J Choi J Baker C Lino M Trigatti B Trajcevski KE Hawke TJ Adeli K 《American journal of physiology. Gastrointestinal and liver physiology》2011,301(2):G326-G337
Intestinal lipid dysregulation is a common feature of insulin-resistant states. The present study investigated alterations in gene expression of key proteins involved in the active absorption of dietary fat and cholesterol in response to development of insulin resistance. Studies were conducted in two diet-induced animal models of insulin resistance: fructose-fed hamster and high-fat-fed mouse. Changes in the mRNA abundance of lipid transporters, adenosine triphosphate cassette (ABC) G5, ABCG8, FA-CoA ligase fatty acid translocase P4, Niemann-Pick C1-Like1 (NPC1L1), fatty acid transport protein 4 (FATP4), and Scavenger Receptor Class B Type I (SR-BI), were assessed in intestinal fragments (duodenum, jejunum, and ileum) using quantitative real-time PCR. Of all the transporters evaluated, SR-B1 showed the most significant changes in both animal models examined. A marked stimulation of SR-B1 expression was observed in all intestinal segments examined in both insulin-resistant animal models. The link between SR-BI expression and intestinal lipoprotein production was then examined in the Caco-2 cell model. SR-B1 overexpression in Caco-2 cells increased apolipoprotein B (apoB) 100 and apoB48 secretion, whereas RNAi knock down of SR-B1 decreased secretion of both apoB100 and apoB48. We also observed changes in subcellular distribution of SR-B1 in response to exogenous lipid and insulin. Confocal microscopy revealed marked changes in SR-BI subcellular distribution in response to both exogenous lipids (oleate) and insulin. In summary, marked stimulation of intestinal SR-BI occurs in vivo in animal models of diet-induced insulin resistance, and modulation of SR-BI in vitro regulates production of apoB-containing lipoprotein particles. We postulate that apical and/or basolateral SR-BI may play an important role in intestinal chylomicron production and may contribute to chylomicron overproduction normally observed in insulin-resistant states. 相似文献
1000.
Couto CA Wang HY Green JC Kiely R Siddaway R Borer C Pears CJ Lakin ND 《The Journal of cell biology》2011,194(3):367-375
Poly adenosine diphosphate (ADP)-ribosylation (PARylation) by poly ADP-ribose (PAR) polymerases (PARPs) is an early response to DNA double-strand breaks (DSBs). In this paper, we exploit Dictyostelium discoideum to uncover a novel role for PARylation in regulating nonhomologous end joining (NHEJ). PARylation occurred at single-strand breaks, and two PARPs, Adprt1b and Adprt2, were required for resistance to this kind of DNA damage. In contrast, although Adprt1b was dispensable for PARylation at DSBs, Adprt1a and, to a lesser extent, Adprt2 were required for this event. Disruption of adprt2 had a subtle impact on the ability of cells to perform NHEJ. However, disruption of adprt1a decreased the ability of cells to perform end joining with a concomitant increase in homologous recombination. PAR-dependent regulation of NHEJ was achieved through promoting recruitment and/or retention of Ku at DSBs. Furthermore, a PAR interaction motif in Ku70 was required for this regulation and efficient NHEJ. These data illustrate that PARylation at DSBs promotes NHEJ through recruitment or retention of repair factors at sites of DNA damage. 相似文献