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Sample records for affect intestinal motility

  1. Pediatric intestinal motility disorders

    PubMed Central

    Gfroerer, Stefan; Rolle, Udo

    2015-01-01

    Pediatric intestinal motility disorders affect many children and thus not only impose a significant impact on pediatric health care in general but also on the quality of life of the affected patient. Furthermore, some of these conditions might also have implications for adulthood. Pediatric intestinal motility disorders frequently present as chronic constipation in toddler age children. Most of these conditions are functional, meaning that constipation does not have an organic etiology, but in 5% of the cases, an underlying, clearly organic disorder can be identified. Patients with organic causes for intestinal motility disorders usually present in early infancy or even right after birth. The most striking clinical feature of children with severe intestinal motility disorders is the delayed passage of meconium in the newborn period. This sign is highly indicative of the presence of Hirschsprung disease (HD), which is the most frequent congenital disorder of intestinal motility. HD is a rare but important congenital disease and the most significant entity of pediatric intestinal motility disorders. The etiology and pathogenesis of HD have been extensively studied over the last several decades. A defect in neural crest derived cell migration has been proven as an underlying cause of HD, leading to an aganglionic distal end of the gut. Numerous basic science and clinical research related studies have been conducted to better diagnose and treat HD. Resection of the aganglionic bowel remains the gold standard for treatment of HD. Most recent studies show, at least experimentally, the possibility of a stem cell based therapy for HD. This editorial also includes rare causes of pediatric intestinal motility disorders such as hypoganglionosis, dysganglionosis, chronic intestinal pseudo-obstruction and ganglioneuromatosis in multiple endocrine metaplasia. Underlying organic pathologies are rare in pediatric intestinal motility disorders but must be recognized as early as

  2. Elenoside increases intestinal motility

    PubMed Central

    Navarro, E; Alonso, SJ; Navarro, R; Trujillo, J; Jorge, E

    2006-01-01

    AIM: To study the effects of elenoside, an arylnaph-thalene lignan from Justicia hyssopifolia, on gastro-intestinal motility in vivo and in vitro in rats. METHODS: Routine in vivo experimental assessments were catharsis index, water percentage of boluses, intestinal transit, and codeine antagonism. The groups included were vehicle control (propylene glycol-ethanol-plant oil-tween 80), elenoside (i.p. 25 and 50 mg/kg), cisapride (i.p. 10 mg/kg), and codeine phosphate (intragastric route, 50 mg/kg). In vitro approaches used isolated rat intestinal tissues (duodenum, jejunum, and ileum). The effects of elenoside at concentrations of 3.2 x 10-4, 6.4 x 10-4 and 1.2 x 10-3 mol/L, and cisapride at 10-6 mol/L were investigated. RESULTS: Elenoside in vivo produced an increase in the catharsis index and water percentage of boluses and in the percentage of distance traveled by a suspension of activated charcoal. Codeine phosphate antagonized the effect of 25 mg/kg of elenoside. In vitro, elenoside in duodenum, jejunum and ileum produced an initial decrease in the contraction force followed by an increase. Elenoside resulted in decreased intestinal frequency in duodenum, jejunum, and ileum. The in vitro and in vivo effects of elenoside were similar to those produced by cisapride. CONCLUSION: Elenoside is a lignan with an action similar to that of purgative and prokinetics drugs. Elenoside, could be an alternative to cisapride in treatment of gastrointestinal diseases as well as a preventive therapy for the undesirable gastrointestinal effects produced by opioids used for mild to moderate pain. PMID:17131476

  3. [Motility disorders of the small intestine in functional intestinal disorders].

    PubMed

    Wingate, D

    1989-02-15

    Functional digestive disorders have their origin in disturbances of the digestive motility control. This control ensured primarily by the "gut brain", which is able to integrate sensitive information from mucosal receptors and to organize an appropriate motor response from a choice of predetermined "programs". The gut brain is in close relationship with the central nervous system (CNS) which collects in fact most of the information and modulates the sensitive integration and the motor response of the enteric nervous system (ENS). Thus, a perturbation of the CNS, such as stress, may induce a dysfunctioning of the ENS, resulting in motor disturbances and finally functional digestive disorders. In a first study involving fasting healthy volunteers, we showed that stress produces a significant reduction of the intestinal migrating motor complexes (MMC). In a second study, patients with irritable bowel syndrome (IBS) were subjected to stress and compared to patients with inflammatory bowel disease and to healthy controls. All subjects exhibited a decrease of MMC; however, total depletion was observed in numerous IBS patients, together with a characteristic irregular motor activity which was associated with symptoms. Finally, 24-hour recordings of the intestinal motility in these patients showed an entirely normal pattern during sleep and when abnormalities just awakening in association with symptoms. Stress-induced perturbation of the CNS in IBS patients seems to provoke an inappropriate modulation of the motor activity programmed by the ENS, resulting in motor disturbances and finally in the symptoms of the disease. PMID:2522225

  4. The effect of gastric inhibitory polypeptide on intestinal glucose absorption and intestinal motility in mice

    SciTech Connect

    Ogawa, Eiichi; Hosokawa, Masaya; Harada, Norio; Yamane, Shunsuke; Hamasaki, Akihiro; Toyoda, Kentaro; Fujimoto, Shimpei; Fujita, Yoshihito; Fukuda, Kazuhito; Tsukiyama, Katsushi; Yamada, Yuichiro; Seino, Yutaka; Inagaki, Nobuya

    2011-01-07

    Research highlights: {yields} Exogenous GIP inhibits intestinal motility through a somatostatin-mediated pathway. {yields} Exogenous GIP inhibits intestinal glucose absorption by reducing intestinal motility. {yields} The GIP-receptor-mediated action in intestine does not involve in GLP-1-mediated pathway. -- Abstract: Gastric inhibitory polypeptide (GIP) is released from the small intestine upon meal ingestion and increases insulin secretion from pancreatic {beta} cells. Although the GIP receptor is known to be expressed in small intestine, the effects of GIP in small intestine are not fully understood. This study was designed to clarify the effect of GIP on intestinal glucose absorption and intestinal motility. Intestinal glucose absorption in vivo was measured by single-pass perfusion method. Incorporation of [{sup 14}C]-glucose into everted jejunal rings in vitro was used to evaluate the effect of GIP on sodium-glucose co-transporter (SGLT). Motility of small intestine was measured by intestinal transit after oral administration of a non-absorbed marker. Intraperitoneal administration of GIP inhibited glucose absorption in wild-type mice in a concentration-dependent manner, showing maximum decrease at the dosage of 50 nmol/kg body weight. In glucagon-like-peptide-1 (GLP-1) receptor-deficient mice, GIP inhibited glucose absorption as in wild-type mice. In vitro examination of [{sup 14}C]-glucose uptake revealed that 100 nM GIP did not change SGLT-dependent glucose uptake in wild-type mice. After intraperitoneal administration of GIP (50 nmol/kg body weight), small intestinal transit was inhibited to 40% in both wild-type and GLP-1 receptor-deficient mice. Furthermore, a somatostatin receptor antagonist, cyclosomatostatin, reduced the inhibitory effect of GIP on both intestinal transit and glucose absorption in wild-type mice. These results demonstrate that exogenous GIP inhibits intestinal glucose absorption by reducing intestinal motility through a somatostatin

  5. SIRT1 inhibits the mouse intestinal motility and epithelial proliferation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    SIRT1 inhibits the mouse intestinal motility and epithelial proliferation. Sirtuin 1 (SIRT1), a NAD+-dependent histone deacetylase, is involved in a wide array of cellular processes, including glucose homeostasis, energy metabolism, proliferation and apoptosis, and immune response. However, it is un...

  6. A computational model of gastro-intestinal motility

    NASA Astrophysics Data System (ADS)

    Wilson, K. F.; Goossens, D. J.

    2001-12-01

    A simulated neural network model of a section of enteric nervous system is presented. The network is a layered feed-forward network consisting of integrate and fire units. The network shows the basic form of intestinal motility; a descending wave of relaxation followed by a wave of contraction. It also shows interesting (but not biologically realistic) spontaneous behaviours when no stimulus is present.

  7. Factors affecting gallbladder motility: drugs.

    PubMed

    Marzio, L

    2003-07-01

    Various drugs and medications that inhibit or stimulate gallbladder contraction and basal tone in humans are described. Active gallbladder contraction may be achieved using synthetic hormones such as cholecystokinin, caerulein and motilin, cholinomimetic drugs such as bethanecol, prostigmine, and erythromycin due to its motilin-like effect. Furthermore, cisapride and cholestyramine, may have some excitatory activity on the gallbladder muscle. Intravenous amino acids also induce gallbladder contraction through the release of cholecystokinin. Inhibition of gallbladder contraction induced by a meal, or reduction of the basal fasting tone may be achieved by using atropine and other cholinergics, and by inhibitory hormones such as somatostatin, the nitric acid releaser arginine, the calcium channel antagonist nifedipine, and progesterone. Other drugs such as trimebutine, loperamide and ondansetron may negatively affect gallbladder contraction. PMID:12974504

  8. Diffused and Sustained Inhibitory Effects of Intestinal Electrical Stimulation on Intestinal Motility Mediated via Sympathetic Pathway

    PubMed Central

    Zhao, Xiaotuan; Yin, Jieyun; Wang, Lijie; Chen, J D Z

    2013-01-01

    Objective The aims was to investigate the energy-dose response effect of IES on small bowel motility, to compare the effect of forward and backward IES; to explore the possibility of using intermittent IES and mechanism of IES on intestinal motility. Material and Methods Five dogs implanted with a duodenal cannula and one pair of intestinal serosal electrodes were studied in 5 sessions: 1) energy-dose response study; 2) forward IES; 3) backward IES; 4) intermittent IES vs. continuous IES; 5) administration of guanethidine. The contractile activity and tonic pressure of the small intestine were recorded. The duration of sustained effect after turning off IES was manually calculated. Results 1) IES with long pulses energy-dose dependently inhibited contractile activity and tonic pressure of the small intestine (p < 0.001). 2) The duration of sustained inhibitory effect of IES on the small intestine depended on the energy of IES delivered (p < 0.001). 3) The potency of the inhibitory effect was the same between forward and backward IES. 4) The efficacy of intermittent IES was the same as continuous IES in inhibiting motility of the small intestine. 5) Guanethidine blocked the inhibitory effect of IES on intestinal motility. Conclusions IES with long pulses inhibits small intestinal motility; the effect is energy-dose dependent, diffused and sustained. Intermittent IES has the same efficacy as the continuous IES in inhibiting small intestinal motility. Forward and backward IES have similar inhibitory effects on small bowel motility. This IES-induced inhibitory effect is mediated via the sympathetic pathway. PMID:23924055

  9. Small intestine motility development in newborn mammals.

    PubMed

    Woliński, Jarosław; Słupecka-Ziemilska, Monika; Boryczka, Maria; Grzesiak, Paulina; Kwiatkowski, Jakub; Kotarba, Grzegorz

    2016-01-01

    Since the beginning of the 20th century, researchers have been working to improve the understanding of gastrointestinal motility. The first major discovery was the observation of a migrating myoelectric complex that turned out to be a universal occurrence among vertebrates. Further inquires resulted in a detailed description of its development during different stages of ontogeny. Some time before that, a cornerstone had been laid for a breakthrough that would come years later. That cornerstone came in the form of interstitial cells of Cajal whose true role could not be discerned until the discovery of a CD117 receptor - their main marker. With the ability to precisely mark interstitial cells of Cajal, a wave of subsequent new experiments and observations connected them to the occurrence of slow waves and allowed an understanding of the mechanism responsible for their generation. Some of these findings suggested that Cajal cells might have a role in the development of several motility disorders thus opening an avenue of research that requires the usage of both traditional and advanced diagnostic methods. PMID:27416626

  10. Small intestine motility development in newborn mammals.

    PubMed

    Woliński, Jarosław; Słupecka-Ziemilska, Monika; Boryczka, Maria; Grzesiak, Paulina; Kwiatkowski, Jakub; Kotarba, Grzegorz

    2016-01-01

    Since the beginning of the 20th century, researchers have been working to improve the understanding of gastrointestinal motility. The first major discovery was the observation of a migrating myoelectric complex that turned out to be a universal occurrence among vertebrates. Further inquires resulted in a detailed description of its development during different stages of ontogeny. Some time before that, a cornerstone had been laid for a breakthrough that would come years later. That cornerstone came in the form of interstitial cells of Cajal whose true role could not be discerned until the discovery of a CD117 receptor - their main marker. With the ability to precisely mark interstitial cells of Cajal, a wave of subsequent new experiments and observations connected them to the occurrence of slow waves and allowed an understanding of the mechanism responsible for their generation. Some of these findings suggested that Cajal cells might have a role in the development of several motility disorders thus opening an avenue of research that requires the usage of both traditional and advanced diagnostic methods.

  11. [Effects of trimebutine on intestinal motility in dogs].

    PubMed

    Hondé, C; Le Gallou, B; Pascaud, X; Junien, J L

    1989-02-15

    The effects of intravenous, oral, intracerebroventricular and local intra-arterial administration of trimebutine were investigated in dogs whose digestive tract had been fitted with electrodes and strain gauge transducers. In fasted conscious dogs, trimebutine (5 mg/kg) stimulated small bowel motility with induction of a propagated phase of regular spiking activity. This stimulation was associated with weak inhibition of gastric motility and a biphasic response of the colon characterized by stimulation followed by inhibition. By the oral route, trimebutine (20 mg/kg) stimulated gastrointestinal motility. The duration of the intestinal migrating phase 2 was increased whereas an additional migrating phase 3 developed. These effects were associated with an increase in colonic contractions lasting two hours. The stimulating effect of trimebutine (phase 3) on intestinal motility was not reproduced after intracerebroventricular administration and was abolished by previous intravenous, but not intraventricular, administration of naloxone. The local effects of trimebutine on the circular muscle of canine gastrointestinal tract were studied after close intra-arterial injection in anesthetized dogs. Under these conditions, the drug stimulated the resting gut through its neural and direct smooth muscle components while it inhibited the contractions induced by field stimulation. In conclusion, the excitatory effect of trimebutine seems to be mediated by mu or delta receptors while its inhibitory activity might involve kappa opiate receptors. PMID:2522226

  12. The virtual intestine: in silico modeling of small intestinal electrophysiology and motility and the applications.

    PubMed

    Du, Peng; Paskaranandavadivel, Niranchan; Angeli, Timothy R; Cheng, Leo K; O'Grady, Gregory

    2016-01-01

    The intestine comprises a long hollow muscular tube organized in anatomically and functionally discrete compartments, which digest and absorb nutrients and water from ingested food. The intestine also plays key roles in the elimination of waste and protection from infection. Critical to all of these functions is the intricate, highly coordinated motion of the intestinal tract, known as motility, which is coregulated by hormonal, neural, electrophysiological and other factors. The Virtual Intestine encapsulates a series of mathematical models of intestinal function in health and disease, with a current focus on motility, and particularly electrophysiology. The Virtual Intestine is being cohesively established across multiple physiological scales, from sub/cellular functions to whole organ levels, facilitating quantitative evaluations that present an integrative in silico framework. The models are also now finding broad physiological applications, including in evaluating hypotheses of slow wave pacemaker mechanisms, smooth muscle electrophysiology, structure-function relationships, and electromechanical coupling. Clinical applications are also beginning to follow, including in the pathophysiology of motility disorders, diagnosing intestinal ischemia, and visualizing colonic dysfunction. These advances illustrate the emerging potential of the Virtual Intestine to effectively address multiscale research challenges in interdisciplinary gastrointestinal sciences.

  13. Spatiotemporal Mapping of Motility in Ex Vivo Preparations of the Intestines

    PubMed Central

    Kendig, Derek M.; Hurst, Norm R.; Grider, John R.

    2016-01-01

    Multiple approaches have been used to record and evaluate gastrointestinal motility including: recording changes in muscle tension, intraluminal pressure, and membrane potential. All of these approaches depend on measurement of activity at one or multiple locations along the gut simultaneously which are then interpreted to provide a sense of overall motility patterns. Recently, the development of video recording and spatiotemporal mapping (STmap) techniques have made it possible to observe and analyze complex patterns in ex vivo whole segments of colon and intestine. Once recorded and digitized, video records can be converted to STmaps in which the luminal diameter is converted to grayscale or color [called diameter maps (Dmaps)]. STmaps can provide data on motility direction (i.e., stationary, peristaltic, antiperistaltic), velocity, duration, frequency and strength of contractile motility patterns. Advantages of this approach include: analysis of interaction or simultaneous development of different motility patterns in different regions of the same segment, visualization of motility pattern changes over time, and analysis of how activity in one region influences activity in another region. Video recordings can be replayed with different timescales and analysis parameters so that separate STmaps and motility patterns can be analyzed in more detail. This protocol specifically details the effects of intraluminal fluid distension and intraluminal stimuli that affect motility generation. The use of luminal receptor agonists and antagonists provides mechanistic information on how specific patterns are initiated and how one pattern can be converted into another pattern. The technique is limited by the ability to only measure motility that causes changes in luminal diameter, without providing data on intraluminal pressure changes or muscle tension, and by the generation of artifacts based upon experimental setup; although, analysis methods can account for these issues

  14. LBP based detection of intestinal motility in WCE images

    NASA Astrophysics Data System (ADS)

    Gallo, Giovanni; Granata, Eliana

    2011-03-01

    In this research study, a system to support medical analysis of intestinal contractions by processing WCE images is presented. Small intestine contractions are among the motility patterns which reveal many gastrointestinal disorders, such as functional dyspepsia, paralytic ileus, irritable bowel syndrome, bacterial overgrowth. The images have been obtained using the Wireless Capsule Endoscopy (WCE) technique, a patented, video colorimaging disposable capsule. Manual annotation of contractions is an elaborating task, since the recording device of the capsule stores about 50,000 images and contractions might represent only the 1% of the whole video. In this paper we propose the use of Local Binary Pattern (LBP) combined with the powerful textons statistics to find the frames of the video related to contractions. We achieve a sensitivity of about 80% and a specificity of about 99%. The achieved high detection accuracy of the proposed system has provided thus an indication that such intelligent schemes could be used as a supplementary diagnostic tool in endoscopy.

  15. Loss of ascl1a prevents secretory cell differentiation within the zebrafish intestinal epithelium resulting in a loss of distal intestinal motility

    PubMed Central

    Roach, Gillian; Wallace, Rachel Heath; Cameron, Amy; Ozel, Rifat Emrah; Hongay, Cintia F.; Baral, Reshica; Andreescu, Silvana; Wallace, Kenneth N.

    2013-01-01

    The vertebrate intestinal epithelium is renewed continuously from stem cells at the base of the crypt in mammals or base of the fold in fish over the life of the organism. As stem cells divide, newly formed epithelial cells make an initial choice between a secretory or enterocyte fate. This choice has previously been demonstrated to involve Notch signaling as well as Atonal and Her transcription factors in both embryogenesis and adults. Here, we demonstrate that in contrast to the atoh1 in mammals, ascl1a is responsible for formation of secretory cells in zebrafish. ascl1a−/− embryos lack all intestinal epithelial secretory cells and instead differentiate into enterocytes. ascl1a−/− embryos also fail to induce intestinal epithelial expression of deltaD suggesting that ascl1a plays a role in initiation of Notch signaling. Inhibition of Notch signaling increases the number of ascl1a and deltaD expressing intestinal epithelial cells as well as the number of developing secretory cells during two specific time periods: between 30 and 34 hpf and again between 64 and 74 hpf. Loss of enteroendocrine products results in loss of anterograde motility in ascl1a−/− embryos. 5HT produced by enterochromaffin cells is critical in motility and secretion within the intestine. We find that addition of exogenous 5HT to ascl1a−/− embryos at near physiological levels (measured by differential pulse voltammetry) induce anterograde motility at similar levels to wild type velocity, distance, and frequency. Removal or doubling the concentration of 5HT in WT embryos does not significantly affect anterograde motility, suggesting that the loss of additional enteroendocrine products in ascl1a−/− embryos also contributes to intestinal motility. Thus, zebrafish intestinal epithelial cells appear to have a common secretory progenitor from which all subtypes form. Loss of enteroendocrine cells reveals the critical need for enteroendocrine products in maintenance of normal

  16. Loss of ascl1a prevents secretory cell differentiation within the zebrafish intestinal epithelium resulting in a loss of distal intestinal motility.

    PubMed

    Roach, Gillian; Heath Wallace, Rachel; Cameron, Amy; Emrah Ozel, Rifat; Hongay, Cintia F; Baral, Reshica; Andreescu, Silvana; Wallace, Kenneth N

    2013-04-15

    The vertebrate intestinal epithelium is renewed continuously from stem cells at the base of the crypt in mammals or base of the fold in fish over the life of the organism. As stem cells divide, newly formed epithelial cells make an initial choice between a secretory or enterocyte fate. This choice has previously been demonstrated to involve Notch signaling as well as Atonal and Her transcription factors in both embryogenesis and adults. Here, we demonstrate that in contrast to the atoh1 in mammals, ascl1a is responsible for formation of secretory cells in zebrafish. ascl1a-/- embryos lack all intestinal epithelial secretory cells and instead differentiate into enterocytes. ascl1a-/- embryos also fail to induce intestinal epithelial expression of deltaD suggesting that ascl1a plays a role in initiation of Notch signaling. Inhibition of Notch signaling increases the number of ascl1a and deltaD expressing intestinal epithelial cells as well as the number of developing secretory cells during two specific time periods: between 30 and 34hpf and again between 64 and 74hpf. Loss of enteroendocrine products results in loss of anterograde motility in ascl1a-/- embryos. 5HT produced by enterochromaffin cells is critical in motility and secretion within the intestine. We find that addition of exogenous 5HT to ascl1a-/- embryos at near physiological levels (measured by differential pulse voltammetry) induce anterograde motility at similar levels to wild type velocity, distance, and frequency. Removal or doubling the concentration of 5HT in WT embryos does not significantly affect anterograde motility, suggesting that the loss of additional enteroendocrine products in ascl1a-/- embryos also contributes to intestinal motility. Thus, zebrafish intestinal epithelial cells appear to have a common secretory progenitor from which all subtypes form. Loss of enteroendocrine cells reveals the critical need for enteroendocrine products in maintenance of normal intestinal motility. PMID

  17. Loss of ascl1a prevents secretory cell differentiation within the zebrafish intestinal epithelium resulting in a loss of distal intestinal motility.

    PubMed

    Roach, Gillian; Heath Wallace, Rachel; Cameron, Amy; Emrah Ozel, Rifat; Hongay, Cintia F; Baral, Reshica; Andreescu, Silvana; Wallace, Kenneth N

    2013-04-15

    The vertebrate intestinal epithelium is renewed continuously from stem cells at the base of the crypt in mammals or base of the fold in fish over the life of the organism. As stem cells divide, newly formed epithelial cells make an initial choice between a secretory or enterocyte fate. This choice has previously been demonstrated to involve Notch signaling as well as Atonal and Her transcription factors in both embryogenesis and adults. Here, we demonstrate that in contrast to the atoh1 in mammals, ascl1a is responsible for formation of secretory cells in zebrafish. ascl1a-/- embryos lack all intestinal epithelial secretory cells and instead differentiate into enterocytes. ascl1a-/- embryos also fail to induce intestinal epithelial expression of deltaD suggesting that ascl1a plays a role in initiation of Notch signaling. Inhibition of Notch signaling increases the number of ascl1a and deltaD expressing intestinal epithelial cells as well as the number of developing secretory cells during two specific time periods: between 30 and 34hpf and again between 64 and 74hpf. Loss of enteroendocrine products results in loss of anterograde motility in ascl1a-/- embryos. 5HT produced by enterochromaffin cells is critical in motility and secretion within the intestine. We find that addition of exogenous 5HT to ascl1a-/- embryos at near physiological levels (measured by differential pulse voltammetry) induce anterograde motility at similar levels to wild type velocity, distance, and frequency. Removal or doubling the concentration of 5HT in WT embryos does not significantly affect anterograde motility, suggesting that the loss of additional enteroendocrine products in ascl1a-/- embryos also contributes to intestinal motility. Thus, zebrafish intestinal epithelial cells appear to have a common secretory progenitor from which all subtypes form. Loss of enteroendocrine cells reveals the critical need for enteroendocrine products in maintenance of normal intestinal motility.

  18. Effects of mosapride on motility of the small intestine and caecum in normal horses after jejunocaecostomy.

    PubMed

    Okamura, Kouichi; Sasaki, Naoki; Kikuchi, Takuya; Murata, Aya; Lee, Inhyung; Yamada, Haruo; Inokuma, Hisashi

    2009-06-01

    The purpose of the present study was to evaluate the prokinetic effects of mosapride with non-invasive assessment of myoelectrical activity in the small intestine and caecum of healthy horses after jejunocaecostomy. Six horses underwent celiotomy and jejunocaecostomy, and were treated with mosapride (treated group) at 1.5 mg/kg per osos once daily for 5 days after surgery. The other six horses did not receive treatment and were used as controls (non-treated group). The electrointestinography (EIG) maximum amplitude was used to measure intestinal motility. Motility significantly decreased following surgery. In the treated group, the EIG maximum amplitude of the small intestine was significantly higher than in the controls from day 6 approximately 31 after treatment. These findings clearly indicate that mosapride could overcome the decline of intestinal motility after jejunocaecostomy in normal horses. PMID:19461212

  19. Effects of mosapride on motility of the small intestine and caecum in normal horses after jejunocaecostomy

    PubMed Central

    Okamura, Kouichi; Kikuchi, Takuya; Murata, Aya; Lee, Inhyung; Yamada, Haruo; Inokuma, Hisashi

    2009-01-01

    The purpose of the present study was to evaluate the prokinetic effects of mosapride with non-invasive assessment of myoelectrical activity in the small intestine and caecum of healthy horses after jejunocaecostomy. Six horses underwent celiotomy and jejunocaecostomy, and were treated with mosapride (treated group) at 1.5 mg/kg per osos once daily for 5 days after surgery. The other six horses did not receive treatment and were used as controls (non-treated group). The electrointestinography (EIG) maximum amplitude was used to measure intestinal motility. Motility significantly decreased following surgery. In the treated group, the EIG maximum amplitude of the small intestine was significantly higher than in the controls from day 6~31 after treatment. These findings clearly indicate that mosapride could overcome the decline of intestinal motility after jejunocaecostomy in normal horses. PMID:19461212

  20. Effect of honey consumption on intestinal motility in male albino rats.

    PubMed

    Alagwu, E A; Egwurugwu, J N; Nneli, R O; Oguike, F; Osim, E E

    2013-01-01

    This study investigated the effects of honey on intestinal motility and transit using twenty (20) male albino rats of Wistar strain weighing 210-220g. The rats were randomly grouped into control and honey-fed (test) groups of ten (10) rats each. The control group was fed on normal rat chow ( Pfizer Company, Nigeria ) and water while the test group was fed on rat feed, water and honey ( 1 ml of honey to every 10 ml initial drinking water daily) for twenty two (22) weeks after which the rats were starved over night before the experiment and sacrificed by stunning. Laparatomy was immediately performed, proximal and distal portions of the intestine identified, cut and put in aerated tyrode solution. Cut sections of the ileum (2-3cm) were mounted on organ bath instrument for motility experiment with varying concentrations of acetylcholine and carbachol. Contractions were recorded as well as the intestinal transit in each group and lengths of intestine with total mean values calculated. Results obtained showed that honey significantly decreased (p<0.01 ) intestinal transit in the test group (21.15±0.75 ) compared with the control group ( 35.96±1.15); decreased intestinal motility in the test group compared with the control and caused significant percentage reduction of intestinal motility with varied concentrations of acetylcholine and carbachol in the test group ( Ach-75.00±0.75%; Carbachol-79.00±0.28%) compared with the control group (Ach-62.00±0.39%; Carbachol-51.00±0.39%). In conclusion, unprocessed Nigerian honey decreased intestinal transit, caused intestinal smooth muscle inhibition and motility and reduced sensitivity of gastrointestinal tract to cholinergic agents. PMID:24937393

  1. Motility patterns of ex vivo intestine segments depend on perfusion mode

    PubMed Central

    Schreiber, Dominik; Jost, Viktor; Bischof, Michael; Seebach, Kristina; Lammers, Wim JEP; Douglas, Rees; Schäfer, Karl-Herbert

    2014-01-01

    AIM: To evaluate and characterize motility patterns from small intestinal gut segments depending on different perfusion media and pressures. METHODS: Experiments were carried out in a custom designed perfusion chamber system to validate and standardise the perfusion technique used. The perfusion chamber was built with a transparent front wall allowing for optical motility recordings and a custom made fastener to hold the intestinal segments. Experiments with different perfusion and storage media combined with different luminal pressures were carried out to evaluate the effects on rat small intestine motility. Software tools which enable the visualization and characterization of intestinal motility in response to different stimuli were used to evaluate the videotaped experiments. The data collected was presented in so called heatmaps thus providing a concise overview of form and strength of contractility patterns. Furthermore, the effect of different storage media on tissue quality was evaluated. Haematoxylin-Eosin stainings were used to compare tissue quality depending on storage and perfusion mode. RESULTS: Intestinal motility is characterized by different repetitive motility patterns, depending on the actual situation of the gut. Different motility patterns could be recorded and characterized depending on the perfusion pressure and media used. We were able to describe at least three different repetitive patterns of intestinal motility in vitro. Patterns with an oral, anal and oro-anal propagation direction could be recorded. Each type of pattern finalized its movement with or without a subsequent distension of the wavefront. Motility patterns could clearly be distinguished in heatmap diagrams. Furthermore undirected motility could be observed. The quantity of the different patterns varies and is highly dependent on the perfusion medium used. Tissue preservation varies depending on the perfusion medium utilized, therefore media with a simple composition as Tyrode

  2. Scintigraphic method for the assessment of intraluminal volume and motility of isolated intestinal segments. [Dogs

    SciTech Connect

    Mitchell, A.; Macey, D.J.; Collin, J.

    1983-07-01

    The isolated in vivo intestinal segment is a popular experimental preparation for the investigation of intestinal function, but its value has been limited because no method has been available for measuring changes in intraluminal volume under experimental conditions. We report a scintigraphic technique for measuring intraluminal volume and assessing intestinal motility. Between 30 and 180 ml, the volume of a 75-cm segment of canine jejunum, perfused with Tc-99m-labeled tin colloid, was found to be proportional to the recorded count rate. This method has been used to monitor the effects of the hormone vasopressin on intestinal function.

  3. Villous motility and unstirred water layers in canine intestine

    SciTech Connect

    Mailman, D.; Womack, W.A.; Kvietys, P.R.; Granger, D.N. )

    1990-02-01

    The possibility that villous motility reduces the mucosal unstirred water layer by mechanical stirring was examined. The frequency of contraction of villi was measured by using videomicroscopic techniques while a segment of anesthetized canine jejunum or ileum with its nerve and blood supply intact was maintained in a sealed chamber through which Tyrode solution was perfused. Radioisotopically labeled inulin, H{sub 2}O, and butyric and lauric acid were used to measure net and/or unidirectional fluxes from the chamber. The unidirectional absorptive transport of H{sub 2}O and butyric acid but not lauric acid by jejunal segments was significantly correlated with flow through the chamber. Plasma volume expansion increased villous motility but decreased the absorption of H{sub 2}O and lauric acid. Absorption of butyric acid from the ileum was little different than from the jejunum although the degree of villous motility was less and net water absorption was greater from the ileum. Absorption of butyric acid into dead tissue indicated that passive diffusion into the tissue accounted for between 7 and 25%, depending on flow rate, of the absorption in intact tissue and that nonspecific binding was low. It was concluded that villous motility did not stir the unstirred water layers and was not directly associated with altered transport.

  4. The involvement of opiate receptors in the effects of trimebutine on intestinal motility in the conscious dog.

    PubMed

    Fioramonti, J; Fargeas, M J; Bueno, L

    1984-09-01

    The effects of intravenous (i.v.) vs intracerebroventricular (i.c.v.) administration of trimebutine on the motility of the small intestine and colon of fasted dogs were assessed using chronic electromyography. Trimebutine, injected intravenously, stimulated small intestinal motility, by inducing a propagated phase of regular spike activity, and inhibited colonic motility for some 4 h. These effects were not reproduced by i.c.v. administration which disrupted the cyclic motor profile of the small intestine for about 2.5 h and did not modify colonic motility. The stimulation of the small intestine motility induced by i.v. administration of the drug was blocked by previous i.v. but not by i.c.v. administration of naloxone. It was concluded that in the dog, the effects of trimebutine on the small intestine but not on the colon, involve peripheral opiate receptors. PMID:6149288

  5. Effect of zinc treatment on intestinal motility in experimentally induced diarrhea in rats.

    PubMed

    Adeniyi, O S; Akomolafe, R O; Ojabo, C O; Eru, E U; Olaleye, S B

    2014-01-01

    Zinc supplementation is a critical new intervention for treating diarrheal episodes in children. Recent studies suggest that administration of zinc along with new low osmolarity oral rehydration solutions / salts (ORS) can reduce the duration and severity of diarrheal episodes for up to three months. Several mechanisms of action of zinc has been proposed, however there is dearth of information about the effect of zinc on intestinal motility during diarrhea. Male albino Wistar rats (80-100g) were used. The effect of different doses of zinc sulphate (25, 50, 100, 150 mg/Kg) on the number of wet faeces was investigated. Intestinal motility during castor oil induced diarrhea was assessed using activated charcoal meal and the mechanisms of action of zinc sulphate on motility were investigated. The effective dose of zinc sulphate (100mg/Kg) significantly reduced (p< 0.001) the number of wet faeces (3.0 ± 0.00) compared with control (6.8 ± 0.25) during diarrhea. This antidiarrheal effect of zinc was abolished by propranolol and nifedipine. Zinc sulphate significantly reduced (p< 0.05) intestinal transit time (60.7 ± 7.13%) compared with control (85.7 ± 2.35%). It is concluded that zinc sulphate reduces the frequency of wet faeces output and intestinal motility during diarrhea via activation of β adrenergic receptor and L-type Ca2+ channel.

  6. Is sperm motility maturation affected by static magnetic fields?

    PubMed Central

    Tablado, L; Pérez-Sánchez, F; Soler, C

    1996-01-01

    Kinematic parameters were evaluated in mouse epididymal extracts to monitor maturation of sperm movement in animals exposed to static magnetic fields using the Sperm-Class Analyzer computerized image analysis system. For this purpose, animals were exposed to a field of 0.7 T generated by a permanent magnet over 10 or 35 days for either 1 or 24 hr/day. The values of the motion endpoints were similar in animals used as controls and in those exposed to the nonionizing radiation, whatever the period of exposure or daily dosage. Changes in motility were observed in all groups: the percentage of total motile and progressive motile spermatozoa increased during passage through the epididymis, with major changes between the caput and corpus epididymides, and the pattern of swimming changed clearly towards more rapid and straighter trajectories. The processes of initiation of sperm motility and maturation of displacement patterns were not then affected by magnetic treatment. Moreover, it appears that sperm production is unaffected because no changes were observed in testicular or epididymal weights after exposure to static magnetic fields. Images Figure 1. Figure 2. Figure 3. PMID:8959411

  7. Effects of psychological stress on small intestinal motility and bacteria and mucosa in mice

    PubMed Central

    Wang, Shao-Xuan; Wu, Wan-Chun

    2005-01-01

    AIM: To investigate the effects of psychological stress on small intestinal motility and bacteria and mucosa in mice, and to explore the relationship between small intestinal dysfunction and small intestinal motility and bacteria and mucosa under psychological stress. METHODS: Sixty mice were randomly divided into psychological stress group and control group. Each group were subdivided into small intestinal motility group (n = 10), bacteria group (n = 10), and D-xylose administered to stomach group (n = 10). An animal model with psychological stress was established housing the mice with a hungry cat in separate layers of a two-layer cage. A semi-solid colored marker (carbon-ink) was used for monitoring small intestinal transit. The proximal small intestine was harvested under sterile condition and processed for quantitation for aerobes (Escherichia coli) and anaerobes (Lactobacilli). The quantitation of bacteria was expressed as log10(colony forming units/g). D-xylose levels in plasma were measured for estimating the damage of small intestinal mucosa. RESULTS: Small intestinal transit was inhibited (39.80±9.50% vs 58.79±11.47%, P<0.01) in mice after psychological stress, compared with the controls. Psychological stress resulted in quantitative alterations in the aerobes (E. coli). There was an increase in the number of E. coli in the proximal small intestinal flora (1.78±0.30 log10(CFU/g) vs 1.37±0.21 log10(CFU/g), P<0.01), and there was decrease in relative proportion of Lactobacilli and E. coli of stressed mice (0.53±0.63 vs 1.14±1.07, P<0.05), while there was no significant difference in the anaerobes (Lactobacilli) between the two groups (2.31±0.70 log10(CFU/g) vs 2.44±0.37 log10(CFU/g), P>0.05). D-xylose concentrations in plasma in psychological stress mice were significantly higher than those in the control group (2.90±0.89 mmol/L vs 0.97±0.33 mmol/L, P<0.01). CONCLUSION: Small intestinal dysfunction under psychological stress may be related to the

  8. Interventions That Affect Gastrointestinal Motility in Hospitalized Adult Patients

    PubMed Central

    Asrani, Varsha M.; Yoon, Harry D.; Megill, Robin D.; Windsor, John A.; Petrov, Maxim S.

    2016-01-01

    Abstract Gastrointestinal (GI) dysmotility is a common complication in acute, critically ill, postoperative, and chronic patients that may lead to impaired nutrient delivery, poor clinical, and patient-reported outcomes. Several pharmacological and nonpharmacological interventions to treat GI dysmotility were investigated in dozens of clinical studies. However, they often yielded conflicting results, at least in part, because various (nonstandardized) definitions of GI dysmotility were used and methodological quality of studies was poor. While a universally accepted definition of GI dysmotility is yet to be developed, a systematic analysis of data derived from double-blind placebo-controlled randomized trials may provide robust data on absolute and relative effectiveness of various interventions as the study outcome (GI motility) was assessed in the least biased manner. To systematically review data from double-blind placebo-controlled randomized trials to determine and compare the effectiveness of interventions that affect GI motility. Three electronic databases (MEDLINE, SCOPUS, and EMBASE) were searched. A random effects model was used for meta-analysis. The summary estimates were reported as mean difference (MD) with the corresponding 95% confidence interval (CI). A total of 38 double-blind placebo-controlled randomized trials involving 2371 patients were eligible for inclusion in the systematic review. These studies investigated a total of 20 different interventions, of which 6 interventions were meta-analyzed. Of them, the use of dopamine receptor antagonists (MD, −8.99; 95% CI, −17.72 to −0.27; P = 0.04) and macrolides (MD, −26.04; 95% CI, −51.25 to −0.82; P = 0.04) significantly improved GI motility compared with the placebo group. The use of botulism toxin significantly impaired GI motility compared with the placebo group (MD, 5.31; 95% CI, −0.04 to 10.67; P = 0.05). Other interventions (dietary factors, probiotics, hormones) did

  9. Effects of trimebutine on intestinal motility after massive small bowel resection.

    PubMed

    Uchiyama, M; Iwafuchi, M; Yagi, M; Iinuma, Y; Kanada, S; Ohtaki, M; Homma, S

    2000-08-01

    Effects of trimebutine maleate (TM) on intestinal motility in short bowel syndrome (SBS) were studied in conscious canines in both acute and chronic phases following 80% massive distal small bowel resection (MSBR). TM was administered orally to beagles with MSBR or as controls in the postprandial and fasting states, and given simultaneously with meals. Intestinal motility was measured using bipolar electrodes for approximately 1 month after the electrodes were implanted in each beagle and the data compared between treatment groups. When TM was given with meals, the postprandial period without duodenal migrating myoelectric (or motor) complexes (MMCs) was shorter than in those given meals only. When TM was given in the postprandial state in short bowel beagles, the initial duodenal MMCs occurred earlier, i.e. the postprandial period was shorter. Diarrhea did not occur in these beagles. When TM was given in the fasting state, duodenal MMCs occurred and propagated to the distal intestine. In conclusion, oral TM administration can produce a more appropriate intestinal condition for the next food intake and make enteral nutrition possible even in the acute phase after MSBR. Such feeding can be carried out without overloading gut function as a result of the modulation of gastrointestinal motility by TM. PMID:11286295

  10. [Effects of trimebutine on motility of the small intestine in humans].

    PubMed

    Couturier, D; Chaussade, S; Grandjouan, S

    1989-02-15

    Trimebutine maleate induces a specific motor response in the human proximal small bowel: except for the few minutes lapse following the occurrence of a spontaneous phase 3, an intravenous injection of 100 mg trimebutine systematically produces, in fed or fasted state, a systemic propagated activity analogous to the spontaneous phase 3 of the migrating motor complex. In lower doses, this effect is not observed. The intraduodenal administration of a high dose (600 mg) induces a similar response to that observed after intravenous injection. Trimebutine possibly acts as a stimulator of peripheral receptors of the enkephalinergic nervous system. Theoretically, these results may result in recommending the therapeutic use of trimebutine in intestinal motility disorders where disappearance or depletion of phase 3 are observed. However, information is still lacking about the relationship between therapeutic activity and the effects on intestinal motility in pathological states. PMID:2537973

  11. The Extracellular Calcium-Sensing Receptor in the Intestine: Evidence for Regulation of Colonic Absorption, Secretion, Motility, and Immunity

    PubMed Central

    Tang, Lieqi; Cheng, Catherine Y.; Sun, Xiangrong; Pedicone, Alexandra J.; Mohamadzadeh, Mansour; Cheng, Sam X.

    2016-01-01

    Different from other epithelia, the intestinal epithelium has the complex task of providing a barrier impeding the entry of toxins, food antigens, and microbes, while at the same time allowing for the transfer of nutrients, electrolytes, water, and microbial metabolites. These molecules/organisms are transported either transcellularly, crossing the apical and basolateral membranes of enterocytes, or paracellularly, passing through the space between enterocytes. Accordingly, the intestinal epithelium can affect energy metabolism, fluid balance, as well as immune response and tolerance. To help accomplish these complex tasks, the intestinal epithelium has evolved many sensing receptor mechanisms. Yet, their roles and functions are only now beginning to be elucidated. This article explores one such sensing receptor mechanism, carried out by the extracellular calcium-sensing receptor (CaSR). In addition to its established function as a nutrient sensor, coordinating food digestion, nutrient absorption, and regulating energy metabolism, we present evidence for the emerging role of CaSR in the control of intestinal fluid homeostasis and immune balance. An additional role in the modulation of the enteric nerve activity and motility is also discussed. Clearly, CaSR has profound effects on many aspects of intestinal function. Nevertheless, more work is needed to fully understand all functions of CaSR in the intestine, including detailed mechanisms of action and specific pathways involved. Considering the essential roles CaSR plays in gastrointestinal physiology and immunology, research may lead to a translational opportunity for the development of novel therapies that are based on CaSR's unique property of using simple nutrients such as calcium, polyamines, and certain amino acids/oligopeptides as activators. It is possible that, through targeting of intestinal CaSR with a combination of specific nutrients, oral solutions that are both inexpensive and practical may be

  12. Ulcerogenic and intestinal motility/transit stimulating actions of nevirapine in albino Wistar rats.

    PubMed

    Umoren, Elizabeth Bassey; Obembe, Agona Odeh; Osim, Eme Effiom

    2013-09-01

    The antiretroviral is a non-nucleoside reverse transcriptase inhibitor of human immunodeficiency virus type 1. This study was undertaken to investigate the effect of nevirapine (NVP) administration on gastric acid secretion, pepsin secretion, mucosal secretion, intestinal motility, and transit using apparently healthy albino Wistar rats. Eighty albino Wistar rats (50-125 g body weight) from the start of the experiment were used for the study. Rats in the control group were fed normal rodent chow, while the NVP group was fed by gavage NVP (0.4 mg/kg body weight) two times daily (07:00 and 18:00 hours) in addition to normal rodent chow for 12 weeks. All animals were allowed free access to clean drinking water. Mean basal gastric output and peak acid output following histamine administration in the NVP-treated group were significantly higher (p < 0.001, respectively) compared to the control. Following cimetidine administration, there was significant decrease (p < 0.001) in peak acid output in the NVP-treated group compared to the control. The concentration of gastric pepsin, adherent mucus secretion, and mean value for ulcer score were significantly higher (p < 0.001) compared to their control group, respectively. There were significant increases (p < 0.05, respectively) in intestinal motility and basal contraction (p < 0.05) and increase in intestinal transit of the ileum of NVP-treated rats compared to their control, respectively. Results of the study suggest that NVP administration might provoke gastric ulceration in rats which may be caused by high pepsin, high basal acid output, and increased intestinal motility and transit. PMID:23536414

  13. Effects of psychological stress on small intestinal motility and expression of cholecystokinin and vasoactive intestinal polypeptide in plasma and small intestine in mice

    PubMed Central

    Cao, Shu-Guang; Wu, Wan-Chun; Han, Zhen; Wang, Meng-Ya

    2005-01-01

    AIM: To investigate the effects of psychological stress on small intestinal motility and expression of cholecystokinin (CCK) and vasoactive intestinal polypeptide (VIP) in plasma and small intestine, and to explore the relationship between small intestinal motor disorders and gastrointestinal hormones under psychological stress. METHODS: Thirty-six mice were randomly divided into psychological stress group and control group. A mouse model with psychological stress was established by housing the mice with a hungry cat in separate layers of a two-layer cage. A semi-solid colored marker (carbon-ink) was used for monitoring small intestinal transit. CCK and VIP levels in plasma and small intestine in mice were measured by radioimmunoassay (RIA). RESULTS: Small intestinal transit was inhibited (52.18±19.15% vs 70.19±17.79%, P<0.01) in mice after psychological stress, compared to the controls. Small intestinal CCK levels in psychological stress mice were significantly lower than those in the control group (0.75±0.53 μg/g vs 1.98±1.17 μg/g, P<0.01), whereas plasma CCK concentrations were not different between the groups. VIP levels in small intestine were significantly higher in psychological stress mice than those in the control group (8.45±1.09 μg/g vs 7.03±2.36 μg/g, P<0.01), while there was no significant difference in plasma VIP levels between the two groups. CONCLUSION: Psychological stress inhibits the small intestinal transit, probably by down-regulating CCK and up-regulating VIP expression in small intestine. PMID:15655834

  14. Host Gut Motility Promotes Competitive Exclusion within a Model Intestinal Microbiota

    PubMed Central

    Baker, Ryan P; Schlomann, Brandon H; Ganz, Julia; Eisen, Judith S; Guillemin, Karen; Parthasarathy, Raghuveer

    2016-01-01

    The gut microbiota is a complex consortium of microorganisms with the ability to influence important aspects of host health and development. Harnessing this “microbial organ” for biomedical applications requires clarifying the degree to which host and bacterial factors act alone or in combination to govern the stability of specific lineages. To address this issue, we combined bacteriological manipulation and light sheet fluorescence microscopy to monitor the dynamics of a defined two-species microbiota within a vertebrate gut. We observed that the interplay between each population and the gut environment produces distinct spatiotemporal patterns. As a consequence, one species dominates while the other experiences sudden drops in abundance that are well fit by a stochastic mathematical model. Modeling revealed that direct bacterial competition could only partially explain the observed phenomena, suggesting that a host factor is also important in shaping the community. We hypothesized the host determinant to be gut motility, and tested this mechanism by measuring colonization in hosts with enteric nervous system dysfunction due to a mutation in the ret locus, which in humans is associated with the intestinal motility disorder known as Hirschsprung disease. In mutant hosts we found reduced gut motility and, confirming our hypothesis, robust coexistence of both bacterial species. This study provides evidence that host-mediated spatial structuring and stochastic perturbation of communities can drive bacterial population dynamics within the gut, and it reveals a new facet of the intestinal host–microbe interface by demonstrating the capacity of the enteric nervous system to influence the microbiota. Ultimately, these findings suggest that therapeutic strategies targeting the intestinal ecosystem should consider the dynamic physical nature of the gut environment. PMID:27458727

  15. Host Gut Motility Promotes Competitive Exclusion within a Model Intestinal Microbiota.

    PubMed

    Wiles, Travis J; Jemielita, Matthew; Baker, Ryan P; Schlomann, Brandon H; Logan, Savannah L; Ganz, Julia; Melancon, Ellie; Eisen, Judith S; Guillemin, Karen; Parthasarathy, Raghuveer

    2016-07-01

    The gut microbiota is a complex consortium of microorganisms with the ability to influence important aspects of host health and development. Harnessing this "microbial organ" for biomedical applications requires clarifying the degree to which host and bacterial factors act alone or in combination to govern the stability of specific lineages. To address this issue, we combined bacteriological manipulation and light sheet fluorescence microscopy to monitor the dynamics of a defined two-species microbiota within a vertebrate gut. We observed that the interplay between each population and the gut environment produces distinct spatiotemporal patterns. As a consequence, one species dominates while the other experiences sudden drops in abundance that are well fit by a stochastic mathematical model. Modeling revealed that direct bacterial competition could only partially explain the observed phenomena, suggesting that a host factor is also important in shaping the community. We hypothesized the host determinant to be gut motility, and tested this mechanism by measuring colonization in hosts with enteric nervous system dysfunction due to a mutation in the ret locus, which in humans is associated with the intestinal motility disorder known as Hirschsprung disease. In mutant hosts we found reduced gut motility and, confirming our hypothesis, robust coexistence of both bacterial species. This study provides evidence that host-mediated spatial structuring and stochastic perturbation of communities can drive bacterial population dynamics within the gut, and it reveals a new facet of the intestinal host-microbe interface by demonstrating the capacity of the enteric nervous system to influence the microbiota. Ultimately, these findings suggest that therapeutic strategies targeting the intestinal ecosystem should consider the dynamic physical nature of the gut environment. PMID:27458727

  16. Diabetes-related dysfunction of the small intestine and the colon: focus on motility.

    PubMed

    Horváth, Viktor József; Putz, Zsuzsanna; Izbéki, Ferenc; Körei, Anna Erzsébet; Gerő, László; Lengyel, Csaba; Kempler, Péter; Várkonyi, Tamás

    2015-11-01

    In contrast to gastric dysfunction, diabetes-related functional impairments of the small and large intestine have been studied less intensively. The gastrointestinal tract accomplishes several functions, such as mixing and propulsion of luminal content, absorption and secretion of ions, water, and nutrients, defense against pathogens, and elimination of waste products. Diverse functions of the gut are regulated by complex interactions among its functional elements, including gut microbiota. The network-forming tissues, the enteric nervous system) and the interstitial cells of Cajal, are definitely impaired in diabetic patients, and their loss of function is closely related to the symptoms in diabetes, but changes of other elements could also play a role in the development of diabetes mellitus-related motility disorders. The development of our understanding over the recent years of the diabetes-induced dysfunctions in the small and large intestine are reviewed in this article.

  17. [Effect of trimebutine on the motility of the normal human small intestines: mechanism of action].

    PubMed

    Chaussade, S; Grandjouan, S; Couturier, D; Thierman-Duffaud, D; Henry, J F

    1987-01-01

    The effects of intravenous trimebutine (TMB) on duodenojejunal motility were investigated in normal subjects in fed and fasted states. The motility was recorded manometrically. In the fasting state TMB 100 mg, 25 min after a spontaneous phase 3 (P3) constantly induced a premature P3. The mean period (means +/- SE) of the migrating motor complex (MMC) cycle decreased from 84 +/- 10.9 to 32.5 +/- 1.0 min. TMB 50 mg, 3 and 25 min after a spontaneous P3 did not significantly modify the periodicity of MMC. TMB 100 mg initiated P3-like activity in post-prandial state. Previous administration of a low dose of naloxone suppressed the stimulating action of TMB. After a TMB injection the motilin plasma level did not vary; a brief increated of PP plasma level was observed. It may be concluded that in the human small intestine TMB included a typical modification of the motility pattern. Opiate receptors might be involved. PMID:3609631

  18. Phytochemical Characteristics of Seeds and Its Effects on the Intestinal Motility and Toxicity of Joannesia princeps.

    PubMed

    Araújo, Adriano Cressoni; Guiguer, Élen Landgraf; Barbalho, Sandra Maria; Bueno, Patrícia C S; Lopes, Juliana Agostinho; da Silva, Bruna Ferreira; Girotto, Letícia Cabrini; de Paula, Marina Guirro; Zeber, Paulo Vitor; de Alvares Goulart, Ricardo

    2016-01-01

    Joannesia princeps is a plant commonly used in folk medicine as laxative for menstrual discomfort and as antihelminthic and antimicrobial to reduce edema and improve tissue healing. The seeds are used in many regions of Brazil as laxative; however, studies are needed to confirm its effectiveness and safety. Thus, the aim of this study was to evaluate the effects of using seeds of this plant on intestinal motility of Wistar rats, evaluate the effects and acute toxicity of its management, as well as determine its phytochemical profile. The evaluation of the effect on the intestinal motility was performed according to the model described by Michelin and Salgado (2004) with modifications. For the evaluation of acute toxicity, we used the model described by Craveiro et al. (2008) and Goloni et al. (2005), and for the analysis of the presence of alkaloids, flavonoids, anthraquinones, steroids, and other components, we used the method described by Carvalho et al. (2006). The results showed that J. princeps exhibits laxative effects similar to those of Senna species such as Cassia angustifolia and the phytochemical analysis of ethanol and aqueous extracts showed the presence of alkaloids, triterpenes, and/or steroids compounds. Acute toxicity showed in the first 12 h: piloerection, contortion, decreased respiratory rate, diarrhea, and weight loss. After this period, these changes were no longer observed. It was concluded that the seeds of this plant have potential laxative activity, confirming the popular use and that the dose of 5 g/kg can be considered safe for consumption.

  19. Endocrine tumour in kidney affecting small bowel structure, motility, and absorptive function 1

    PubMed Central

    Gleeson, M. H.; Bloom, S. R.; Polak, J. M.; Henry, K.; Dowling, R. H.

    1971-01-01

    A 44-year-old woman is described with an endocrine tumour arising in the kidney. There were associated abnormalities of small intestinal morphology, motility, and absorptive function. These abnormalities reversed on removal of the tumour. Detailed studies showed that the tumour contained, and was secreting, glucagon. It is postulated that the intestinal abnormalities may have resulted from glucagon itself or another, as yet unidentified, hormone. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6 PMID:4941684

  20. Sodium affects the sperm motility in the European eel.

    PubMed

    Vílchez, M Carmen; Morini, Marina; Peñaranda, David S; Gallego, Víctor; Asturiano, Juan F; Pérez, Luz

    2016-08-01

    The role of seminal plasma sodium and activation media sodium on sperm motility was examined by selectively removing the element from these two media, in European eel sperm. Sperm size (sperm head area) was also measured using an ASMA (Automated Sperm Morphometry Analyses) system, in the different conditions. Intracellular sodium [Na(+)]i was quantitatively analyzed by first time in the spermatozoa from a marine fish species. Measurement of [Na(+)]i was done before and after motility activation, by Flow Cytometry, using CoroNa Green AM as a dye. Sperm motility activation induced an increase in [Na(+)]i, from 96.72mM in quiescent stage to 152.21mM post-activation in seawater. A significant decrease in sperm head area was observed post-activation in seawater. There was a notable reduction in sperm motility when sodium was removed from the seminal plasma, but not when it was removed from the activation media. Sodium removal was also linked to a significant reduction in sperm head area in comparison to the controls. Our results indicate that the presence of the ion Na(+) in the seminal plasma (or in the extender medium) is necessary for the preservation of sperm motility in European eel, probably because it plays a role in maintaining an appropriate sperm cell volume in the quiescent stage of the spermatozoa. PMID:27085371

  1. Effect of trimebutine on intestinal motility and plasma motilin in the dog.

    PubMed

    Poitras, P; Honde, C; Havrankova, J; Lahaie, R G; Trudel, L; Goyer, R; Junien, J L; Pascaud, X

    1986-09-01

    In a previous report, trimebutine was shown to induce premature periods of phase III activity in fasting dogs, and its action was blocked by naloxone. In this study, we observed that trimebutine (5 mg X kg-1 iv) could induce premature phase IIIs in canine small intestine during interdigestive and digestive periods; trimebutine-induced phase IIIs were migrating along the small intestine faster than spontaneous activity fronts and; trimebutine-induced phase IIIs were accompanied by sharp rises in concentrations of plasma motilin. To further elucidate the trimebutine-stimulatory mechanism, we verified its effects on the release of various circulating peptides that influence intestinal motility: short-interval blood sampling during trimebutine infusion revealed that plasma motilin increases induced by trimebutine preceded the beginning of phase III in proximal duodenum; and gastrin and insulin postprandial releases were abolished by trimebutine. Therefore, trimebutine, by its simultaneous but opposite effects on various peptides that individually carry positive (e.g., motilin) or negative (e.g., gastrin and insulin) influences on the generation of activity fronts, could alter the equilibrium between stimulatory and inhibitory forces in such a way that, in some circumstances (e.g., postprandial period), stimulatory mechanisms become predominant. PMID:3529986

  2. Intestinal invasion of Salmonella enterica serovar Typhimurium in the avian host is dose dependent and does not depend on motility and chemotaxis.

    PubMed

    Olsen, John Elmerdahl; Hoegh-Andersen, Kirsten Hobolt; Rosenkrantz, Jesper Tjørnholt; Schroll, Casper; Casadesús, Josep; Aabo, Søren; Christensen, Jens Peter

    2013-08-30

    Salmonella enterica serotype Typhimurium (S. Typhimurium) can invade in the intestine of the avian host, and knowledge on the mechanisms that govern this is potentially important for prevention of disease. This study investigated the invasion of S. Typhimurium in the avian host and to which extent it depended on motility and chemotaxis. Wild type and previously well-characterized transposon mutants in flagella genes fliC and fljB and in chemotaxis genes cheA, cheB and cheR were used as challenge strains in intestinal loop experiments. Invasion was shown to be dose dependent, but did not require functional flagella or chemotaxis genes. In support of the results from intestinal loop experiments, flagella and chemotaxis genes were not significantly important to the outcome of an oral infection. The results showed that S. Typhimurium invasion in the avian host was dose dependent and was not affected by the loss of flagella and chemotaxis genes.

  3. The Semen pH Affects Sperm Motility and Capacitation

    PubMed Central

    Hong, Zhiwei; Xie, Min; Chen, Shengrong; Yao, Bing

    2015-01-01

    As the chemical environment of semen can have a profound effect on sperm quality, we examined the effect of pH on the motility, viability and capacitation of human sperm. The sperm in this study was collected from healthy males to avoid interference from other factors. The spermatozoa cultured in sperm nutrition solution at pH 5.2, 6.2, 7.2 and 8.2 were analyzed for sperm total motility, progressive motility (PR), hypo-osmotic swelling (HOS) rate, and sperm penetration. Our results showed that these parameters were similar in pH 7.2 and 8.2 sperm nutrition solutions, but decreased in pH 5.2 and 6.2 solutions. The HOS rate exhibited positive correlation with the sperm total motility and PR. In addition, the sperm Na+/K+-ATPase activity at different pHs was measured, and the enzyme activity was significantly lower in pH 5.2 and 6.2 media, comparing with that in pH 8.2 and pH 7.2 solutions. Using flow cytometry (FCM) and laser confocal scanning microscopy (LCSM) analysis, the intracellular Ca2+ concentrations of sperm cultured in sperm capacitation solution at pH 5.2, 6.2, 7.2 and 8.2 were determined. Compared with that at pH 7.2, the mean fluorescence intensity of sperm in pH 5.2 and 6.2 media decreased significantly, while that of pH 8.2 group showed no difference. Our results suggested that the declined Na+/K+-ATPase activity at acidic pHs result in decreased sperm movement and capacitation, which could be one of the mechanisms of male infertility. PMID:26173069

  4. The Semen pH Affects Sperm Motility and Capacitation.

    PubMed

    Zhou, Ji; Chen, Li; Li, Jie; Li, Hongjun; Hong, Zhiwei; Xie, Min; Chen, Shengrong; Yao, Bing

    2015-01-01

    As the chemical environment of semen can have a profound effect on sperm quality, we examined the effect of pH on the motility, viability and capacitation of human sperm. The sperm in this study was collected from healthy males to avoid interference from other factors. The spermatozoa cultured in sperm nutrition solution at pH 5.2, 6.2, 7.2 and 8.2 were analyzed for sperm total motility, progressive motility (PR), hypo-osmotic swelling (HOS) rate, and sperm penetration. Our results showed that these parameters were similar in pH 7.2 and 8.2 sperm nutrition solutions, but decreased in pH 5.2 and 6.2 solutions. The HOS rate exhibited positive correlation with the sperm total motility and PR. In addition, the sperm Na(+)/K(+)-ATPase activity at different pHs was measured, and the enzyme activity was significantly lower in pH 5.2 and 6.2 media, comparing with that in pH 8.2 and pH 7.2 solutions. Using flow cytometry (FCM) and laser confocal scanning microscopy (LCSM) analysis, the intracellular Ca2(+ )concentrations of sperm cultured in sperm capacitation solution at pH 5.2, 6.2, 7.2 and 8.2 were determined. Compared with that at pH 7.2, the mean fluorescence intensity of sperm in pH 5.2 and 6.2 media decreased significantly, while that of pH 8.2 group showed no difference. Our results suggested that the declined Na(+)/K(+)-ATPase activity at acidic pHs result in decreased sperm movement and capacitation, which could be one of the mechanisms of male infertility.

  5. Graded effects of unregulated smooth muscle myosin on intestinal architecture, intestinal motility and vascular function in zebrafish.

    PubMed

    Abrams, Joshua; Einhorn, Zev; Seiler, Christoph; Zong, Alan B; Sweeney, H Lee; Pack, Michael

    2016-05-01

    Smooth muscle contraction is controlled by the regulated activity of the myosin heavy chain ATPase (Myh11). Myh11 mutations have diverse effects in the cardiovascular, digestive and genitourinary systems in humans and animal models. We previously reported a recessive missense mutation, meltdown (mlt), which converts a highly conserved tryptophan to arginine (W512R) in the rigid relay loop of zebrafish Myh11. The mlt mutation disrupts myosin regulation and non-autonomously induces invasive expansion of the intestinal epithelium. Here, we report two newly identified missense mutations in the switch-1 (S237Y) and coil-coiled (L1287M) domains of Myh11 that fail to complement mlt Cell invasion was not detected in either homozygous mutant but could be induced by oxidative stress and activation of oncogenic signaling pathways. The smooth muscle defect imparted by the mlt and S237Y mutations also delayed intestinal transit, and altered vascular function, as measured by blood flow in the dorsal aorta. The cell-invasion phenotype induced by the three myh11 mutants correlated with the degree of myosin deregulation. These findings suggest that the vertebrate intestinal epithelium is tuned to the physical state of the surrounding stroma, which, in turn, governs its response to physiologic and pathologic stimuli. Genetic variants that alter the regulation of smooth muscle myosin might be risk factors for diseases affecting the intestine, vasculature, and other tissues that contain smooth muscle or contractile cells that express smooth muscle proteins, particularly in the setting of redox stress. PMID:26893369

  6. Roles of sphincter of Oddi motility and serum vasoactive intestinal peptide, gastrin and cholecystokinin octapeptide

    PubMed Central

    Zhang, Zhen-Hai; Qin, Cheng-Kun; Wu, Shuo-Dong; Xu, Jian; Cui, Xian-Ping; Wang, Zhi-Yi; Xian, Guo-Zhe

    2014-01-01

    AIM: To investigate roles of sphincter of Oddi (SO) motility played in pigment gallbladder stone formation in model of guinea pigs. METHODS: Thirty-four adult male Hartley guinea pigs were divided randomly into two groups: the control group and pigment stone group. The pigment stone group was divided into 4 subgroups with 6 guinea pigs each according to time of sacrifice, and were fed a pigment lithogenic diet and sacrificed after 3, 6, 9 and 12 wk. SO manometry and recording of myoelectric activity of the guinea pigs were obtained by multifunctional physiograph at each stage. Serum vasoactive intestinal peptide (VIP), gastrin and cholecystokinin octapeptide (CCK-8) were detected at each stage in the process of pigment gallbladder stone formation by enzyme-linked immunosorbent assay. RESULTS: The incidence of pigment gallstone formation was 0%, 0%, 16.7% and 66.7% in the 3-, 6-, 9- and 12-wk group, respectively. The frequency of myoelectric activity decreased in the 3-wk group. The amplitude of myoelectric activity had a tendency to decrease but not significantly. The frequency of the SO decreased significantly in the 9-wk group. The SO basal pressure and common bile duct pressure increased in the 12-wk group (25.19 ± 7.77 mmHg vs 40.56 ± 11.81 mmHg, 22.35 ± 7.60 mmHg vs 38.51 ± 11.57 mmHg, P < 0.05). Serum VIP was significantly elevated in the 6- and 12-wk groups and serum CCK-8 was decreased significantly in the 12-wk group. CONCLUSION: Pigment gallstone-causing diet may induce SO dysfunction. The tension of the SO increased. The disturbance in SO motility may play a role in pigment gallstone formation, and changes in serum VIP and CCK-8 may be important causes of SO dysfunction. PMID:24782626

  7. Combined effects of fungal alkaloids on intestinal motility in an in vitro rat model.

    PubMed

    Dalziel, J E; Dunstan, K E; Finch, S C

    2013-11-01

    Diarrhea is caused by factors that alter absorption and secretion of water and ions across the intestinal epithelium and disrupt motility. Parasitic infection, stress, poor nutrition, and exposure to plant or fungal toxins predispose livestock to noninfectious diarrhea. This is more prevalent in sheep that graze pastures infected with wild-type endophytic fungus, suggesting the involvement of fungal alkaloids. These increase smooth muscle contraction: ergovaline/ergotamine (ergot alkaloid) activates serotonin (5-HT) receptors, and lolitrem B (indole diterpene) inhibits large-conductance Ca2+-activated K+ (BK) channels. Because of their separate mechanisms of action the objective of this study was to investigate whether they act synergistically to increase smooth muscle contraction. Effects of ergotamine (1 µM) and lolitrem B (0.1 µM) on the tension and frequency of spontaneous contractions were investigated in a longitudinal preparation of isolated distal colon. The compounds were dissolved in 0.1% dimethyl sulfoxide (DMSO) and applied separately or together for 1 h. Ergotamine increased contractile tension compared to the pretreatment control (P<0.01) and produced a short-lived increase in frequency (P<0.001). Lolitrem B increased contractile tension (P<0.05) but had no effect on frequency. When applied together, the contractile tension was greater than the sum of the compounds applied separately (P<0.05). The frequency of contractions was increased (P<0.05) but was not significantly different from that for ergotamine alone. The increased contractile tension when both compounds were applied together indicates that ergotamine and lolitrem B acted synergistically to increase smooth muscle contraction, suggesting that they would alter motility in vivo.

  8. Graded effects of unregulated smooth muscle myosin on intestinal architecture, intestinal motility and vascular function in zebrafish

    PubMed Central

    Abrams, Joshua; Einhorn, Zev; Seiler, Christoph; Zong, Alan B.; Sweeney, H. Lee; Pack, Michael

    2016-01-01

    ABSTRACT Smooth muscle contraction is controlled by the regulated activity of the myosin heavy chain ATPase (Myh11). Myh11 mutations have diverse effects in the cardiovascular, digestive and genitourinary systems in humans and animal models. We previously reported a recessive missense mutation, meltdown (mlt), which converts a highly conserved tryptophan to arginine (W512R) in the rigid relay loop of zebrafish Myh11. The mlt mutation disrupts myosin regulation and non-autonomously induces invasive expansion of the intestinal epithelium. Here, we report two newly identified missense mutations in the switch-1 (S237Y) and coil-coiled (L1287M) domains of Myh11 that fail to complement mlt. Cell invasion was not detected in either homozygous mutant but could be induced by oxidative stress and activation of oncogenic signaling pathways. The smooth muscle defect imparted by the mlt and S237Y mutations also delayed intestinal transit, and altered vascular function, as measured by blood flow in the dorsal aorta. The cell-invasion phenotype induced by the three myh11 mutants correlated with the degree of myosin deregulation. These findings suggest that the vertebrate intestinal epithelium is tuned to the physical state of the surrounding stroma, which, in turn, governs its response to physiologic and pathologic stimuli. Genetic variants that alter the regulation of smooth muscle myosin might be risk factors for diseases affecting the intestine, vasculature, and other tissues that contain smooth muscle or contractile cells that express smooth muscle proteins, particularly in the setting of redox stress. PMID:26893369

  9. The role of selenium in intestinal motility and morphology in a murine model of Typanosoma cruzi infection

    PubMed Central

    de Souza, Andréa Pereira; Sieberg, Ryan; Li, Hua; Cahill, Hannah R.; Zhao, Dazhi; Araújo-Jorge, Tania C.; Tanowitz, Herbert B.

    2010-01-01

    Infection with Trypanosoma cruzi causes mega-syndromes of the gastrointestinal (GI) tract in humans and animals. In the present study, we employed magnetic resonance imaging to non-invasively monitor the effect of selenium supplementation on alterations in the GI tract of T. cruzi-infected mice. CD1 mice infected with T. cruzi (Brazil strain) exhibited dilatation of the intestines similar to that we recently reported in infected C57Bl/6 mice. The average intestine lumen diameter increased by 65% and the increase was reduced to 29% in mice supplemented with 2 ppm selenium in the drinking water. When supplemented with 3 ppm selenium in chow the lumen diameter was also significantly reduced although the difference between the infected and infected supplemented mice was smaller. Intestinal motility in infected mice fed with selenium-enriched chow was increased compared with infected mice fed with normal unsupplemented chow and was not significantly different from intestinal motility in uninfected mice. We suggest that Se may be used to modulate the inflammatory, immunological, and/or antioxidant responses involved in intestinal disturbances caused by T. cruzi infection. PMID:20195635

  10. Two cholecystokinin receptor subtypes are identified in goldfish, being the CCKAR involved in the regulation of intestinal motility.

    PubMed

    Tinoco, A B; Valenciano, A I; Gómez-Boronat, M; Blanco, A M; Nisembaum, L G; De Pedro, N; Delgado, M J

    2015-09-01

    Cholecystokinin (CCK) plays a key role in the digestive physiology of vertebrates. However, very little is known about the role of CCK on intestinal functions in fish. The present study identifies two CCK receptor subtypes in a stomachless teleost, the goldfish (Carassius auratus), and investigates by using an in vitro system their involvement mediating the effects of the sulfated octapeptide of CCK (CCK-8S) on the motility of isolated proximal intestine. Partial-length mRNAs encoding two CCK receptor isoforms (CCKAR and CCKBR.I) were sequenced and the structural analysis showed that both receptors belong to the G-protein coupled receptor superfamily. Both goldfish CCK receptor sequences were more closely related to zebrafish sequences, sharing the lowest similarities with cavefish and tilapia. The highest expression of goldfish CCKAR was observed along the whole intestine whereas the CCKBR gen was predominantly expressed in the hypothalamus, vagal lobe and posterior intestine. Application of CCK-8S to the organ bath evoked a concentration-dependent contractile response in intestine strips. The contractions were not blocked by either tetrodotoxin or atropine, suggesting that CCK-8S acts on the gut smooth muscle directly. Preincubations of intestine strips with devazepide and L365,260 (CCKAR and CCKBR receptor selective antagonists) showed that the CCK-8S-induced contraction could be partially mediated by the CCKAR receptor subtype, which is also the most abundant CCK receptor found in gastrointestinal tissues. In conclusion, two CCK receptors with a differential distribution pattern has been identified in goldfish, and the CCKAR subtype is mainly involved in the regulation of intestinal motility by the CCK-8S. PMID:26051613

  11. Two cholecystokinin receptor subtypes are identified in goldfish, being the CCKAR involved in the regulation of intestinal motility.

    PubMed

    Tinoco, A B; Valenciano, A I; Gómez-Boronat, M; Blanco, A M; Nisembaum, L G; De Pedro, N; Delgado, M J

    2015-09-01

    Cholecystokinin (CCK) plays a key role in the digestive physiology of vertebrates. However, very little is known about the role of CCK on intestinal functions in fish. The present study identifies two CCK receptor subtypes in a stomachless teleost, the goldfish (Carassius auratus), and investigates by using an in vitro system their involvement mediating the effects of the sulfated octapeptide of CCK (CCK-8S) on the motility of isolated proximal intestine. Partial-length mRNAs encoding two CCK receptor isoforms (CCKAR and CCKBR.I) were sequenced and the structural analysis showed that both receptors belong to the G-protein coupled receptor superfamily. Both goldfish CCK receptor sequences were more closely related to zebrafish sequences, sharing the lowest similarities with cavefish and tilapia. The highest expression of goldfish CCKAR was observed along the whole intestine whereas the CCKBR gen was predominantly expressed in the hypothalamus, vagal lobe and posterior intestine. Application of CCK-8S to the organ bath evoked a concentration-dependent contractile response in intestine strips. The contractions were not blocked by either tetrodotoxin or atropine, suggesting that CCK-8S acts on the gut smooth muscle directly. Preincubations of intestine strips with devazepide and L365,260 (CCKAR and CCKBR receptor selective antagonists) showed that the CCK-8S-induced contraction could be partially mediated by the CCKAR receptor subtype, which is also the most abundant CCK receptor found in gastrointestinal tissues. In conclusion, two CCK receptors with a differential distribution pattern has been identified in goldfish, and the CCKAR subtype is mainly involved in the regulation of intestinal motility by the CCK-8S.

  12. A novel tachykinin NK2 receptor antagonist prevents motility-stimulating effects of neurokinin A in small intestine

    PubMed Central

    Lördal, Mikael; Navalesi, Giovanni; Theodorsson, Elvar; Maggi, Carlo A; Hellström, Per M

    2001-01-01

    MEN 11420 (nepadutant) is a potent, selective and competitive antagonist of tachykinin NK2 receptors. The objective of the present study was to assess the capability of the drug to antagonize the stimulatory effects of neurokinin A (NKA) on gastrointestinal motility, as well as to change the fasting migrating motor complex (MMC). Thirty-four male volunteers were randomized to treatment with either placebo or MEN 11420 in a double-blinded manner. Effects of MEN 11420 (8 mg intravenously) were evaluated as changes in phases I, II and III of MMC, as well as contraction frequency, amplitude and motility index during baseline conditions and during stimulation of motility using NKA (25 pmol kg−1 min−1 intravenously). NKA preceded by placebo increased the fraction of time occupied by phase II, increased contraction frequency, amplitude and motility index. MEN 11420 effectively antagonized the motility-stimulating effects of NKA. MEN 11420 reduced the phase II-stimulating effect of NKA. In addition, the stimulatory effect of NKA on contraction frequency and amplitude, as well as motility index were inhibited by MEN 11420. MEN 11420 did not affect the characteristics of MMC during saline infusion. Plasma levels of MEN 11420 peaked during the first hour after infusion and decreased to less than half during the first 2 h. In conclusion, intravenous MEN 11420 effectively inhibited NKA-stimulated, but not basal gastrointestinal motility, and was well tolerated by all subjects. PMID:11522614

  13. Pro-inflammatory flagellin proteins of prevalent motile commensal bacteria are variably abundant in the intestinal microbiome of elderly humans.

    PubMed

    Neville, B Anne; Sheridan, Paul O; Harris, Hugh M B; Coughlan, Simone; Flint, Harry J; Duncan, Sylvia H; Jeffery, Ian B; Claesson, Marcus J; Ross, R Paul; Scott, Karen P; O'Toole, Paul W

    2013-01-01

    Some Eubacterium and Roseburia species are among the most prevalent motile bacteria present in the intestinal microbiota of healthy adults. These flagellate species contribute "cell motility" category genes to the intestinal microbiome and flagellin proteins to the intestinal proteome. We reviewed and revised the annotation of motility genes in the genomes of six Eubacterium and Roseburia species that occur in the human intestinal microbiota and examined their respective locus organization by comparative genomics. Motility gene order was generally conserved across these loci. Five of these species harbored multiple genes for predicted flagellins. Flagellin proteins were isolated from R. inulinivorans strain A2-194 and from E. rectale strains A1-86 and M104/1. The amino-termini sequences of the R. inulinivorans and E. rectale A1-86 proteins were almost identical. These protein preparations stimulated secretion of interleukin-8 (IL-8) from human intestinal epithelial cell lines, suggesting that these flagellins were pro-inflammatory. Flagellins from the other four species were predicted to be pro-inflammatory on the basis of alignment to the consensus sequence of pro-inflammatory flagellins from the β- and γ- proteobacteria. Many fliC genes were deduced to be under the control of σ(28). The relative abundance of the target Eubacterium and Roseburia species varied across shotgun metagenomes from 27 elderly individuals. Genes involved in the flagellum biogenesis pathways of these species were variably abundant in these metagenomes, suggesting that the current depth of coverage used for metagenomic sequencing (3.13-4.79 Gb total sequence in our study) insufficiently captures the functional diversity of genomes present at low (≤1%) relative abundance. E. rectale and R. inulinivorans thus appear to synthesize complex flagella composed of flagellin proteins that stimulate IL-8 production. A greater depth of sequencing, improved evenness of sequencing and improved

  14. Listeria monocytogenes DNA Glycosylase AdlP Affects Flagellar Motility, Biofilm Formation, Virulence, and Stress Responses

    PubMed Central

    Zhang, Ting; Bae, Dongryeoul

    2016-01-01

    ABSTRACT The temperature-dependent alteration of flagellar motility gene expression is critical for the foodborne pathogen Listeria monocytogenes to respond to a changing environment. In this study, a genetic determinant, L. monocytogenes f2365_0220 (lmof2365_0220), encoding a putative protein that is structurally similar to the Bacillus cereus alkyl base DNA glycosylase (AlkD), was identified. This determinant was involved in the transcriptional repression of flagellar motility genes and was named adlP (encoding an AlkD-like protein [AdlP]). Deletion of adlP activated the expression of flagellar motility genes at 37°C and disrupted the temperature-dependent inhibition of L. monocytogenes motility. The adlP null strains demonstrated decreased survival in murine macrophage-like RAW264.7 cells and less virulence in mice. Furthermore, the deletion of adlP significantly decreased biofilm formation and impaired the survival of bacteria under several stress conditions, including the presence of a DNA alkylation compound (methyl methanesulfonate), an oxidative agent (H2O2), and aminoglycoside antibiotics. Our findings strongly suggest that adlP may encode a bifunctional protein that transcriptionally represses the expression of flagellar motility genes and influences stress responses through its DNA glycosylase activity. IMPORTANCE We discovered a novel protein that we named AlkD-like protein (AdlP). This protein affected flagellar motility, biofilm formation, and virulence. Our data suggest that AdlP may be a bifunctional protein that represses flagellar motility genes and influences stress responses through its DNA glycosylase activity. PMID:27316964

  15. Depletion of enteroendocrine and mucus-secreting cells is associated with colorectal carcinogenesis severity and impaired intestinal motility in rats.

    PubMed

    Novaes, Rômulo Dias; Sequetto, Priscila Lima; Vilela Gonçalves, Reggiani; Cupertino, Marli Carmo; Santos, Eliziária Cardoso; Mello, Vanessa Joia; Araújo, Marta Rocha; Silva, Edson; Oliveira, Tânia Toledo

    2016-01-01

    This study investigated the relationship between enteroendocrine and mucus-secreting cells distribution, the severity of colonic mucosal injury and intestinal motility in experimental colorectal carcinogenesis. Using a standardized murine model of colorectal carcinogenesis, eight-weeks-old female Wistar rats weighting 147.30 ± 29.15g were randomized into two groups receiving a subcutaneous injection of 0.9% saline (control) or the chemical carcinogen 1,2-dimethylhydrazine (DMH) at 20 mg/kg per week during 10 weeks. Aberrant crypt foci (ACF) were more frequent in DMH group compared to control group (P < 0.001). The number of enteroendocrine and mucus-secreting cells, and intestinal motility was reduced in DMH animals (P < 0.05). The distribution of enteric neurons was similar in both groups. In DMH animals there was a direct correlation between colonic motility and distribution of enteroendocrine (R(2)  = 0.68, P < 0.05) and mucus-secreting cells (R(2)  = 0.77, P < 0.05). Inverse correlation between the number of ACF, mucus-secreting cells (R(2)  = -0.57, P < 0.05), and enteroendocrine cells (R(2)  = -0.74, P < 0.05) was also observed. There was inverse correlation between the severity of the mucosal lesion, the number of mucus-secreting cells (R(2)  = -0.83, P < 0.05) and enteroendocrine cells (R(2)  = -0.96, P < 0.05). There was a direct correlation between nucleolar organizer regions (AgNOR) and ACF number (R(2)  = 0.62; P < 0.01). Inverse correlation was also found between AgNOR, the number of mucus-secreting cells (R(2)  = -0.76; P < 0.001), and enteroendocrine cells (R(2)  = -0.86; P < 0.001). Taken together, the results indicated that colonic malignant transformation is related to depletion of mucus-secreting and enteroendocrine cells, which was a useful indicator of the evolutionary status of intestinal neoplasm, partially explaining the intestinal motility disorders in the

  16. Gastrointestinal Motility Disorders in Children

    PubMed Central

    Ambartsumyan, Lusine

    2014-01-01

    The most common and challenging gastrointestinal motility disorders in children include gastroesophageal reflux disease (GERD), esophageal achalasia, gastroparesis, chronic intestinal pseudo-obstruction, and constipation. GERD is the most common gastrointestinal motility disorder affecting children and is diagnosed clinically and treated primarily with acid secretion blockade. Esophageal achalasia, a less common disorder in the pediatric patient population, is characterized by dysphagia and treated with pneumatic balloon dilation and/or esophagomyotomy. Gastroparesis and chronic intestinal pseudo-obstruction are poorly characterized in children and are associated with significant morbidity. Constipation is among the most common complaints in children and is associated with significant morbidity as well as poor quality of life. Data on epidemiology and outcomes, clinical trials, and evaluation of new diagnostic techniques are needed to better diagnose and treat gastrointestinal motility disorders in children. We present a review of the conditions and challenges related to these common gastrointestinal motility disorders in children. PMID:24799835

  17. Campylobacter jejuni pdxA Affects Flagellum-Mediated Motility to Alter Host Colonization

    PubMed Central

    Asakura, Hiroshi; Hashii, Noritaka; Uema, Masashi; Kawasaki, Nana; Sugita-Konishi, Yoshiko; Igimi, Shizunobu; Yamamoto, Shigeki

    2013-01-01

    Vitamin B6 (pyridoxal-5'-phosphate, PLP) is linked to a variety of biological functions in prokaryotes. Here, we report that the pdxA (putative 4-hydroxy-L-threonine phosphate dehydrogenase) gene plays a pivotal role in the PLP-dependent regulation of flagellar motility, thereby altering host colonization in a leading foodborne pathogen, Campylobacter jejuni. A C. jejuni pdxA mutant failed to produce PLP and exhibited a coincident loss of flagellar motility. Mass spectrometric analyses showed a 3-fold reduction in the main flagellar glycan pseudaminic acid (Pse) associated with the disruption of pdxA. The pdxA mutant also exhibited reduced growth rates compared with the WT strain. Comparative metabolomic analyses revealed differences in respiratory/energy metabolism between WT C. jejuni and the pdxA mutant, providing a possible explanation for the differential growth fitness between the two strains. Consistent with the lack of flagellar motility, the pdxA mutant showed impaired motility-mediated responses (bacterial adhesion, ERK1/2 activation, and IL-8 production) in INT407 cells and reduced colonization of chickens compared with the WT strain. Overall, this study demonstrated that the pdxA gene affects the PLP-mediated flagellar motility function, mainly through alteration of Pse modification, and the disruption of this gene also alters the respiratory/energy metabolisms to potentially affect host colonization. Our data therefore present novel implications regarding the utility of PLP and its dependent enzymes as potent target(s) for the control of this pathogen in the poultry host. PMID:23936426

  18. Secondary metabolites from nonhost plants affect the motility and viability of phytopathogenic Aphanomyces cochlioides zoospores.

    PubMed

    Islam, Md Tofazzal

    2008-01-01

    The motile zoospores of the damping-off pathogen Aphanomyces cochlioides aggregate on host plants (e.g., sugar beet, spinach) guided by the host-specific plant signal cochliophilin A before infection. To assess the potential role of secondary metabolites in nonhost resistance, acetone extracts of 200 nonhost traditional medicinal plants from Chinese and Bangladeshi origins were tested for the motility behaviour of A. cochlioides zoospores using a particle bioassay method. Nearly one third of the tested plant extracts exhibited diverse deleterious activities such as repellent, stimulant, motility halting and lysis against A. cochlioides zoospores. Among these active plants, an extract of the Chinese medicinal plant Dalbergia odorifera displayed potent repellent activity toward zoospores. Chromatographic separation of D. odorifera constituents revealed that the repellent activity was regulated by the cumulative effect of three motility-affecting isoflavonoids, viz. (+/-)-medicarpin (repellent at 150 microg/ml), (-)-claussequinone (stimulant at 100 microg/ml) and formononetin (stimulant and attractant at 50 microg/ml). A mixture (1:1:1, w/w/w) of these three compounds exhibited only repellent activity toward zoospores at a concentration lower than 50 microg/ml. These results suggest that nonhost plants might possess potential bioactive secondary metabolites to ward off zoosporic phytopathogens. PMID:18533468

  19. How the Motility Pattern of Bacteria Affects Their Dispersal and Chemotaxis

    PubMed Central

    Taktikos, Johannes; Stark, Holger; Zaburdaev, Vasily

    2013-01-01

    Most bacteria at certain stages of their life cycle are able to move actively; they can swim in a liquid or crawl on various surfaces. A typical path of the moving cell often resembles the trajectory of a random walk. However, bacteria are capable of modifying their apparently random motion in response to changing environmental conditions. As a result, bacteria can migrate towards the source of nutrients or away from harmful chemicals. Surprisingly, many bacterial species that were studied have several distinct motility patterns, which can be theoretically modeled by a unifying random walk approach. We use this approach to quantify the process of cell dispersal in a homogeneous environment and show how the bacterial drift velocity towards the source of attracting chemicals is affected by the motility pattern of the bacteria. Our results open up the possibility of accessing additional information about the intrinsic response of the cells using macroscopic observations of bacteria moving in inhomogeneous environments. PMID:24391710

  20. Mannose-Binding Lectin Inhibits the Motility of Pathogenic Salmonella by Affecting the Driving Forces of Motility and the Chemotactic Response

    PubMed Central

    Nakamura, Shuichi; Islam, Md. Shafiqul; Guo, Yijie; Ihara, Kohei; Tomioka, Rintaro; Masuda, Mizuki; Yoneyama, Hiroshi; Isogai, Emiko

    2016-01-01

    Mannose-binding lectin (MBL) is a key pattern recognition molecule in the lectin pathway of the complement system, an important component of innate immunity. MBL functions as an opsonin which enhances the sequential immune process such as phagocytosis. We here report an inhibitory effect of MBL on the motility of pathogenic bacteria, which occurs by affecting the energy source required for motility and the signaling pathway of chemotaxis. When Salmonella cells were treated with a physiological concentration of MBL, their motile fraction and free-swimming speed decreased. Rotation assays of a single flagellum showed that the flagellar rotation rate was significantly reduced by the addition of MBL. Measurements of the intracellular pH and membrane potential revealed that MBL affected a driving force for the Salmonella flagellum, the electrochemical potential difference of protons. We also found that MBL treatment increased the reversal frequency of Salmonella flagellar rotation, which interfered with the relative positive chemotaxis toward an attractive substrate. We thus propose that the motility inhibition effect of MBL may be secondarily involved in the attack against pathogens, potentially facilitating the primary role of MBL in the complement system. PMID:27104738

  1. Trimebutine-induced phase III-like activity in infants with intestinal motility disorders.

    PubMed

    Boige, N; Cargill, G; Mashako, L; Cezard, J P; Navarro, J

    1987-01-01

    Duodenal manometric recordings were performed in five male children (mean age 11.7 +/- 6.8 months) suffering from severe digestive pathology with clinical findings of dysmotility; they required total parenteral nutrition: one case of enteropathy following intestinal resection for congenital small bowel atresia, and four cases of intestinal pseudoobstruction. The basal 3-h fasting recordings showed complete disorganization of interdigestive activity characterized by an absence of migrating motor complexes and a marked basal hypomotility with motor indices lower than in control subjects. Intravenous trimebutine (3 mg/kg) produced a phase III-like activity 88 +/- 121 s after administration in four cases. The activity lasted 236 +/- 105 s and had a mean frequency of 11.75 +/- 0.86 waves/min. It was propagated aborally in the two patients having two duodenal recording sites. Trimebutine-induced phase III activity was followed by signs of peristalsis in two patients. PMID:3430262

  2. An experimental method to identify neurogenic and myogenic active mechanical states of intestinal motility

    PubMed Central

    Costa, Marcello; Wiklendt, Lukasz; Arkwright, John W.; Spencer, Nicholas J.; Omari, Taher; Brookes, Simon J. H.; Dinning, Phil G.

    2013-01-01

    Excitatory and inhibitory enteric neural input to intestinal muscle acting on ongoing myogenic activity determines the rich repertoire of motor patterns involved in digestive function. The enteric neural activity cannot yet be established during movement of intact intestine in vivo or in vitro. We propose the hypothesis that is possible to deduce indirectly, but reliably, the state of activation of the enteric neural input to the muscle from measurements of the mechanical state of the intestinal muscle. The fundamental biomechanical model on which our hypothesis is based is the “three-element model” proposed by Hill. Our strategy is based on simultaneous video recording of changes in diameters and intraluminal pressure with a fiber-optic manometry in isolated segments of rabbit colon. We created a composite spatiotemporal map (DPMap) from diameter (DMap) and pressure changes (PMaps). In this composite map rhythmic myogenic motor patterns can readily be distinguished from the distension induced neural peristaltic contractions. Plotting the diameter changes against corresponding pressure changes at each location of the segment, generates “orbits” that represent the state of the muscle according to its ability to contract or relax actively or undergoing passive changes. With a software developed in MatLab, we identified twelve possible discrete mechanical states and plotted them showing where the intestine actively contracted and relaxed isometrically, auxotonically or isotonically, as well as where passive changes occurred or was quiescent. Clustering all discrete active contractions and relaxations states generated for the first time a spatio-temporal map of where enteric excitatory and inhibitory neural input to the muscle occurs during physiological movements. Recording internal diameter by an impedance probe proved equivalent to measuring external diameter, making possible to further develop similar strategy in vivo and humans. PMID:23596400

  3. Curcuma longa L. as a Therapeutic Agent in Intestinal Motility Disorders. 2: Safety Profile in Mouse

    PubMed Central

    Micucci, Matteo; Aldini, Rita; Cevenini, Monica; Colliva, Carolina; Spinozzi, Silvia; Roda, Giulia; Montagnani, Marco; Camborata, Cecilia; Camarda, Luca; Chiarini, Alberto; Mazzella, Giuseppe; Budriesi, Roberta

    2013-01-01

    Background Curcuma extract exerts a myorelaxant effect on the mouse intestine. In view of a possible use of curcuma extract in motor functional disorders of the gastrointestinal tract, a safety profile study has been carried out in the mouse. Methods Thirty mice were used to study the in vitro effect of curcuma on gallbladder, bladder, aorta and trachea smooth muscular layers and hearth inotropic and chronotropic activity. The myorelaxant effect on the intestine was also thoroughly investigated. Moreover, curcuma extract (200 mg/Kg/day) was orally administered to twenty mice over 28 days and serum liver and lipids parameters were evaluated. Serum, bile and liver bile acids qualitative and quantitative composition was were also studied. Results In the intestine, curcuma extract appeared as a not competitive inhibitor through cholinergic, histaminergic and serotoninergic receptors and showed spasmolytic effect on K+ induced contraction at the level of L type calcium channels. No side effect was observed on bladder, aorta, trachea and heart when we used a dose that is effective on the intestine. An increase in gallbladder tone and contraction was observed. Serum liver and lipids parameters were normal, while a slight increase in serum and liver bile acids concentration and a decrease in bile were observed. Conclusions Although these data are consistent with the safety of curcuma extract as far as its effect on the smooth muscular layers of different organs and on the heart, the mild cholestatic effect observed in absence of alteration of liver function tests must be further evaluated and the effective dose with minimal side effects considered. PMID:24260512

  4. Radiologic observations of gastric and small intestinal motility in suckling pigs.

    PubMed

    Wood, A K

    1982-01-01

    The passage of a single oral dose of barium sulfate through the stomach and small intestine of 18 pigs (1 to 21 days of age) was studied. In a series of lateral radiographs, the stomach had a smooth oval appearance, filling the cranial third of the abdomen. Barium mixed rapidly with the milk clot in the stomach immediately after swallowing and became distributed throughout the stomach (except for the diverticulum, which contained gas). Barium passed into the duodenum by postdosing minute (PDM) 3 in 1 pig, and by PDM 10 in 11 pigs. In 32 experiments in 17 pigs, gastric emptying of barium was complete by PDM 100 in 91% of the experiments, whether or not the pigs had suckled the sow. Suckling also did not influence the time taken for barium to reach the large intestine (by PDM 360 in 12 pigs). When a hyperosmolar contrast medium (diatrizoate meglumine) was given instead of barium sulfate to 10 pigs, gastric emptying was delayed (it was not complete by up to PDM 218), but the small intestine filled rapidly (the contrast medium reached the cecum by PDM 218).

  5. Effect of antiorthostatic BedRest (BR) on GastroIntestinal Motility (GIM) of normal subjects

    NASA Technical Reports Server (NTRS)

    Putcha, L.; Hunter, R. P.; Tietze, K. J.; Cintron, N. M.

    1992-01-01

    The combined effects of postural changes, fluid shifts and diuresis associated with the absence of the gravity vector may decrease gastrointestinal motility (GIM) during space flight. GIM can be estimated from the mouth to cecum transit time (MCTT) of orally administered lactulose (LAC); this test is used to assess changes in GIM in normal subjects and in patients with GI pathology and related disease conditions. Since bedrest (BR) mimics some of the physiological changes that occur during space flight, the effect of ten days of BR on GIM was evaluated from the MCTT of LAC. Methods: Subjects were 12 nonsmoking males between the ages of 35 and 50. After an 8-10 hour fast, subjects ingested Cephulac (registered) (20 g solution) with a low-fiber breakfast on four different days (45, 30, 25, and 20) before BR and on three separate days (4, 7, and 10) during BR. Breath-H2 concentrations were measured before and at 10 minute intervals for 4 hours after breakfast using a Quintron breathalyzer and MCTT was determined from these data. Results: MCTT ranged between 10 and 122 minutes during ambulation and 80 to 120 minutes during BR with means of 79 minutes and 122 minutes respectively. Conclusion: Mean MCTT during BR was 54 percent longer than during ambulation, suggesting that absorption and availability of orally administered medications and nutrients may be delayed or impaired as a result of decreased GIM during bedrest.

  6. Nivalenol and deoxynivalenol affect rat intestinal epithelial cells: a concentration related study.

    PubMed

    Bianco, Giuseppe; Fontanella, Bianca; Severino, Lorella; Quaroni, Andrea; Autore, Giuseppina; Marzocco, Stefania

    2012-01-01

    The integrity of the gastrointestinal tract represents a crucial first level defence against ingested toxins. Among them, Nivalenol is a trichotecenes mycotoxin frequently found on cereals and processed grains; when it contaminates human food and animal feed it is often associated with another widespread contaminant, Deoxynivalenol. Following their ingestion, intestinal epithelial cells are exposed to concentrations of these trichothecenes high enough to cause mycotoxicosis. In this study we have investigated the effects of Nivalenol and Deoxynivalenol on intestinal cells in an in vitro model system utilizing the non-tumorigenic rat intestinal epithelial cell line IEC-6. Both Nivalenol and Deoxynivalenol (5-80 µM) significantly affected IEC-6 viability through a pro-apoptotic process which mainly involved the following steps: (i) Bax induction; (ii) Bcl-2 inhibition, and (iii) caspase-3 activation. Moreover, treatment with Nivalenol produced a significant cell cycle arrest of IEC-6 cells, primarily at the G(0)/G(1) interphase and in the S phase, with a concomitant reduction in the fraction of cells in G(2). Interestingly, when administered at lower concentrations (0.1-2.5 µM), both Nivalenol and Deoxynivalenol affected epithelial cell migration (restitution), representing the initial step in gastrointestinal wound healing in the gut. This reduced motility was associated with significant remodelling of the actin cytoskeleton, and changes in expression of connexin-43 and focal adhesion kinase. The concentration range of Nivalenol or Deoxynivalenol we have tested is comparable with the mean estimated daily intake of consumers eating contaminated food. Thus, our results further highlight the risks associated with intake of even low levels of these toxins. PMID:23251682

  7. Nivalenol and deoxynivalenol affect rat intestinal epithelial cells: a concentration related study.

    PubMed

    Bianco, Giuseppe; Fontanella, Bianca; Severino, Lorella; Quaroni, Andrea; Autore, Giuseppina; Marzocco, Stefania

    2012-01-01

    The integrity of the gastrointestinal tract represents a crucial first level defence against ingested toxins. Among them, Nivalenol is a trichotecenes mycotoxin frequently found on cereals and processed grains; when it contaminates human food and animal feed it is often associated with another widespread contaminant, Deoxynivalenol. Following their ingestion, intestinal epithelial cells are exposed to concentrations of these trichothecenes high enough to cause mycotoxicosis. In this study we have investigated the effects of Nivalenol and Deoxynivalenol on intestinal cells in an in vitro model system utilizing the non-tumorigenic rat intestinal epithelial cell line IEC-6. Both Nivalenol and Deoxynivalenol (5-80 µM) significantly affected IEC-6 viability through a pro-apoptotic process which mainly involved the following steps: (i) Bax induction; (ii) Bcl-2 inhibition, and (iii) caspase-3 activation. Moreover, treatment with Nivalenol produced a significant cell cycle arrest of IEC-6 cells, primarily at the G(0)/G(1) interphase and in the S phase, with a concomitant reduction in the fraction of cells in G(2). Interestingly, when administered at lower concentrations (0.1-2.5 µM), both Nivalenol and Deoxynivalenol affected epithelial cell migration (restitution), representing the initial step in gastrointestinal wound healing in the gut. This reduced motility was associated with significant remodelling of the actin cytoskeleton, and changes in expression of connexin-43 and focal adhesion kinase. The concentration range of Nivalenol or Deoxynivalenol we have tested is comparable with the mean estimated daily intake of consumers eating contaminated food. Thus, our results further highlight the risks associated with intake of even low levels of these toxins.

  8. Prenatal Intestinal Obstruction Affects the Myenteric Plexus and Causes Functional Bowel Impairment in Fetal Rat Experimental Model of Intestinal Atresia

    PubMed Central

    Khen-Dunlop, Naziha; Sarnacki, Sabine; Victor, Anais; Grosos, Celine; Menard, Sandrine; Soret, Rodolphe; Goudin, Nicolas; Pousset, Maud; Sauvat, Frederique; Revillon, Yann; Cerf-Bensussan, Nadine; Neunlist, Michel

    2013-01-01

    Background Intestinal atresia is a rare congenital disorder with an incidence of 3/10 000 birth. About one-third of patients have severe intestinal dysfunction after surgical repair. We examined whether prenatal gastrointestinal obstruction might effect on the myenteric plexus and account for subsequent functional disorders. Methodology/Principal Findings We studied a rat model of surgically induced antenatal atresia, comparing intestinal samples from both sides of the obstruction and with healthy rat pups controls. Whole-mount preparations of the myenteric plexus were stained for choline acetyltransferase (ChAT) and nitric oxide synthase (nNOS). Quantitative reverse transcription PCR was used to analyze mRNAs for inflammatory markers. Functional motility and permeability analyses were performed in vitro. Phenotypic studies were also performed in 8 newborns with intestinal atresia. In the experimental model, the proportion of nNOS-immunoreactive neurons was similar in proximal and distal segments (6.7±4.6% vs 5.6±4.2%, p = 0.25), but proximal segments contained a higher proportion of ChAT-immunoreactive neurons (13.2±6.2% vs 7.5±4.3%, p = 0.005). Phenotypic changes were associated with a 100-fold lower concentration-dependent contractile response to carbachol and a 1.6-fold higher EFS-induced contractile response in proximal compared to distal segments. Transcellular (p = 0.002) but not paracellular permeability was increased. Comparison with controls showed that modifications involved not only proximal but also distal segments. Phenotypic studies in human atresia confirmed the changes in ChAT expression. Conclusion Experimental atresia in fetal rat induces differential myenteric plexus phenotypical as well as functional changes (motility and permeability) between the two sides of the obstruction. Delineating these changes might help to identify markers predictive of motility dysfunction and to define guidelines for post-surgical care. PMID:23667464

  9. The arylalkylamine-N-acetyltransferase (AANAT) acetylates dopamine in the digestive tract of goldfish: a role in intestinal motility.

    PubMed

    Nisembaum, Laura Gabriela; Tinoco, A B; Moure, A L; Alonso Gómez, A L; Delgado, M J; Valenciano, A I

    2013-05-01

    Melatonin has been found in the digestive tract of many vertebrates. However, the enzymatic activity of the arylalkylamine-N-acetyltransferase (AANAT) and the hydroxindole-O-methyltransferase (HIOMT), the last two enzymes of melatonin biosynthesis, have been only measured in rat liver. Therefore, the first objective of the present study is to investigate the functionality of these enzymes in the liver and gut of goldfish, analyzing its possible daily changes and comparing its catalytic properties with those from the retina isoforms. The daily rhythms with nocturnal acrophases in retinal AANAT and HIOMT activities support their role in melatonin biosynthesis. In foregut AANAT activity also show a daily rhythm while in liver and hindgut significant but not rhythmic levels of AANAT activity are found. HIOMT activity is not detected in any of these peripheral tissues suggesting an alternative role for AANAT besides melatonin synthesis. The failure to detect functional HIOMT activity in both, liver and gut, led us to investigate other physiological substrates for the AANAT, as dopamine, searching alternative roles for this enzyme in the goldfish gut. Dopamine competes with tryptamine and inhibits retinal, intestinal and hepatic N-acetyltryptamine production, suggesting that the active isoform in gut is AANAT1. Besides, gut and liver produces N-acetyldopamine in presence of acetyl coenzyme-A and dopamine. This production is not abolished by the presence of folic acid (arylamine N-acetyltransferase inhibitor) in any studied tissue, but a total inhibition occurs in the presence of CoA-S-N-acetyltryptamine (AANAT inhibitor) in liver. Therefore, AANAT1 seems to be an important enzyme in the regulation of dopamine and N-acetyldopamine content in liver. Finally, for the first time in fish we found that dopamine, but not N-acetyldopamine, regulates the gut motility, underlying the broad physiological role of AANAT in the gut.

  10. Exposure to environmentally relevant concentrations of genistein during activation does not affect sperm motility in the fighting fish Betta splendens.

    PubMed

    Clotfelter, Ethan D; Gendelman, Hannah K

    2014-01-01

    Sperm collected from male fighting fish Betta splendens were activated in control water, water containing the ion-channel blocker gadolinium (a putative positive control), or water containing the isoflavone phytoestrogen genistein to determine the effects of acute genistein exposure on male reproductive function. Computer-assisted sperm analysis was used to quantify the proportion of sperm that were motile and the swimming velocity of those sperm. The highest concentration of gadolinium (100 μ M) tested was effective at reducing sperm motility and velocity, but neither concentration of genistein tested (3.7 nM or 3.7 μ M) significantly affected these sperm parameters. Our findings suggest that acute exposure to waterborne phytoestrogens during activation does not reduce the motility of fish sperm.

  11. Exposure to Environmentally Relevant Concentrations of Genistein during Activation Does Not Affect Sperm Motility in the Fighting Fish Betta splendens

    PubMed Central

    Clotfelter, Ethan D.; Gendelman, Hannah K.

    2014-01-01

    Sperm collected from male fighting fish Betta splendens were activated in control water, water containing the ion-channel blocker gadolinium (a putative positive control), or water containing the isoflavone phytoestrogen genistein to determine the effects of acute genistein exposure on male reproductive function. Computer-assisted sperm analysis was used to quantify the proportion of sperm that were motile and the swimming velocity of those sperm. The highest concentration of gadolinium (100 μM) tested was effective at reducing sperm motility and velocity, but neither concentration of genistein tested (3.7 nM or 3.7 μM) significantly affected these sperm parameters. Our findings suggest that acute exposure to waterborne phytoestrogens during activation does not reduce the motility of fish sperm. PMID:24516856

  12. Exposure to environmentally relevant concentrations of genistein during activation does not affect sperm motility in the fighting fish Betta splendens.

    PubMed

    Clotfelter, Ethan D; Gendelman, Hannah K

    2014-01-01

    Sperm collected from male fighting fish Betta splendens were activated in control water, water containing the ion-channel blocker gadolinium (a putative positive control), or water containing the isoflavone phytoestrogen genistein to determine the effects of acute genistein exposure on male reproductive function. Computer-assisted sperm analysis was used to quantify the proportion of sperm that were motile and the swimming velocity of those sperm. The highest concentration of gadolinium (100 μ M) tested was effective at reducing sperm motility and velocity, but neither concentration of genistein tested (3.7 nM or 3.7 μ M) significantly affected these sperm parameters. Our findings suggest that acute exposure to waterborne phytoestrogens during activation does not reduce the motility of fish sperm. PMID:24516856

  13. ALDH isozymes downregulation affects cell growth, cell motility and gene expression in lung cancer cells

    PubMed Central

    Moreb, Jan S; Baker, Henry V; Chang, Lung-Ji; Amaya, Maria; Lopez, M Cecilia; Ostmark, Blanca; Chou, Wayne

    2008-01-01

    Background Aldehyde dehydrogenase isozymes ALDH1A1 and ALDH3A1 are highly expressed in non small cell lung cancer. Neither the mechanisms nor the biologic significance for such over expression have been studied. Methods We have employed oligonucleotide microarrays to analyze changes in gene profiles in A549 lung cancer cell line in which ALDH activity was reduced by up to 95% using lentiviral mediated expression of siRNA against both isozymes (Lenti 1+3). Stringent analysis methods were used to identify gene expression patterns that are specific to the knock down of ALDH activity and significantly different in comparison to wild type A549 cells (WT) or cells similarly transduced with green fluorescent protein (GFP) siRNA. Results We confirmed significant and specific down regulation of ALDH1A1 and ALDH3A1 in Lenti 1+3 cells and in comparison to 12 other ALDH genes detected. The results of the microarray analysis were validated by real time RT-PCR on RNA obtained from Lenti 1+3 or WT cells treated with ALDH activity inhibitors. Detailed functional analysis was performed on 101 genes that were significantly different (P < 0.001) and their expression changed by ≥ 2 folds in the Lenti 1+3 group versus the control groups. There were 75 down regulated and 26 up regulated genes. Protein binding, organ development, signal transduction, transcription, lipid metabolism, and cell migration and adhesion were among the most affected pathways. Conclusion These molecular effects of the ALDH knock-down are associated with in vitro functional changes in the proliferation and motility of these cells and demonstrate the significance of ALDH enzymes in cell homeostasis with a potentially significant impact on the treatment of lung cancer. PMID:19025616

  14. TLR signalling affects sperm mitochondrial function and motility via phosphatidylinositol 3-kinase and glycogen synthase kinase-3α.

    PubMed

    Zhu, Xingxing; Shi, Dongyan; Li, Xiaoqian; Gong, Weijuan; Wu, Fengjiao; Guo, Xuejiang; Xiao, Hui; Liu, Lixin; Zhou, Hong

    2016-03-01

    Infection in male and female genital tracts can lead to infertility. The underlying mechanisms of this process remain unclear. Toll-like receptors (TLRs) recognize conserved structures and respond to pathogens by initiating signals that activate inflammatory gene transcription. Here, we demonstrate that TLR activation in sperm reduces sperm motility via signalling through myeloid differentiation factor 88 (MyD88), phosphatidylinositol 3-kinase (PI3K), and glycogen synthase kinase (GSK)-3α. Upon TLR activation, phosphorylated forms of PI3K and GSK3α were detected in the mitochondria, and the mitochondrial membrane potential was impaired in sperm. In addition, mitochondrial ATP levels were decreased after TLR agonist stimulation. Furthermore, blocking PI3K or GSK3α activation abrogated these effects and reversed the TLR-induced reduction in sperm motility. These results identify a previously unrecognized TLR signalling pathway that leads to dysfunctional sperm mitochondria, which reduce sperm motility. Our study reveals a novel mechanism by which pathogenic infection affects sperm motility and possibly leads to infertility.

  15. Listeria monocytogenes DNA glycosylase AdiP affects flagellar motility, biofilm formation, virulence, and stress responses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The temperature-dependent alteration of flagellar motility gene expression is critical for the foodborne pathogen Listeria monocytogenes to respond to a changing environment. In this study, a genetic determinant, L. monocytogenes f2365_0220 (lmof2365_0220), encoding a putative protein that is struct...

  16. Bacterial Shape and ActA Distribution Affect Initiation of Listeria monocytogenes Actin-Based Motility

    PubMed Central

    Rafelski, Susanne M.; Theriot, Julie A.

    2005-01-01

    We have examined the process by which the intracellular bacterial pathogen Listeria monocytogenes initiates actin-based motility and determined the contribution of the variable surface distribution of the ActA protein to initiation and steady-state movement. To directly correlate ActA distributions to actin dynamics and motility of live bacteria, ActA was fused to a monomeric red fluorescent protein (mRFP1). Actin comet tail formation and steady-state bacterial movement rates both depended on ActA distribution, which in turn was tightly coupled to the bacterial cell cycle. Motility initiation was found to be a highly complex, multistep process for bacteria, in contrast to the simple symmetry breaking previously observed for ActA-coated spherical beads. F-actin initially accumulated along the sides of the bacterium and then slowly migrated to the bacterial pole expressing the highest density of ActA as a tail formed. Early movement was highly unstable with extreme changes in speed and frequent stops. Over time, saltatory motility and sensitivity to the immediate environment decreased as bacterial movement became robust at a constant steady-state speed. PMID:15980176

  17. Palmitoylethanolamide normalizes intestinal motility in a model of post-inflammatory accelerated transit: involvement of CB1 receptors and TRPV1 channels

    PubMed Central

    Capasso, Raffaele; Orlando, Pierangelo; Pagano, Ester; Aveta, Teresa; Buono, Lorena; Borrelli, Francesca; Di Marzo, Vincenzo; Izzo, Angelo A

    2014-01-01

    Background and Purpose Palmitoylethanolamide (PEA), a naturally occurring acylethanolamide chemically related to the endocannabinoid anandamide, interacts with targets that have been identified in peripheral nerves controlling gastrointestinal motility, such as cannabinoid CB1 and CB2 receptors, TRPV1 channels and PPARα. Here, we investigated the effect of PEA in a mouse model of functional accelerated transit which persists after the resolution of colonic inflammation (post-inflammatory irritable bowel syndrome). Experimental Approach Intestinal inflammation was induced by intracolonic administration of oil of mustard (OM). Mice were tested for motility and biochemical and molecular biology changes 4 weeks later. PEA, oleoylethanolamide and endocannabinoid levels were measured by liquid chromatography-mass spectrometry and receptor and enzyme mRNA expression by qRT-PCR. Key Results OM induced transient colitis and a functional post-inflammatory increase in upper gastrointestinal transit, associated with increased intestinal anandamide (but not 2-arachidonoylglycerol, PEA or oleoylethanolamide) levels and down-regulation of mRNA for TRPV1 channels. Exogenous PEA inhibited the OM-induced increase in transit and tended to increase anandamide levels. Palmitic acid had a weaker effect on transit. Inhibition of transit by PEA was blocked by rimonabant (CB1 receptor antagonist), further increased by 5′-iodoresiniferatoxin (TRPV1 antagonist) and not significantly modified by the PPARα antagonist GW6471. Conclusions and Implications Intestinal endocannabinoids and TRPV1 channel were dysregulated in a functional model of accelerated transit exhibiting aspects of post-inflammatory irritable bowel syndrome. PEA counteracted the accelerated transit, the effect being mediated by CB1 receptors (possibly via increased anandamide levels) and modulated by TRPV1 channels. PMID:24818658

  18. Motility of Pseudomonas aeruginosa in saturated granular media as affected by chemoattractant.

    PubMed

    Chen, Jiazhou; Jin, Yan

    2011-09-25

    To examine and quantify the effects of glass beads and chemoattractant on bacterial motility in granular media, we examined the motile behavior of P. aeruginosa in a saturated granular medium and quantified the effects of glass beads and the presence of a chemoattractant. By recording individual cell trajectories in microfluidic channels under a high-speed confocal microscope, we directly measured the cell's run direction and corresponding run-length, speed and turn angle. Bacterial run speed increased in the presence of chemoattractant in both aqueous and granular media. But it decreased in glass-beads compared to in aqueous media due to the restricted pore geometry and interactions between bacteria and grain surfaces. Notably, the relatively higher frequency distribution at turn angles of 170° decreased dramatically, while the smaller peak at 70° increased and became dominant on a bimodal distribution, showing more bacteria changed directions at smaller turn angles rather than reverse their swimming directions. Additionally, the presence of glass beads also decreased the chemotactic velocity and random motility by similar proportions due to the restrictive geometry and the interactions between bacteria and glass beads surface. Our study indicates that the swimming parameters measured from aqueous media cannot be directly adopted in models for predicting bacteria travel in granular media.

  19. Race Affects Outcome among Infants with Intestinal Failure

    PubMed Central

    Squires, Robert H; Balint, Jane; Horslen, Simon; Wales, Paul W.; Soden, Jason; Duggan, Christopher; Li, Ruosha; Belle, Steven H

    2014-01-01

    Objective Intestinal failure is a rare, devastating condition associated with significant morbidity and mortality. We sought to determine if ethnic and racial differences were associated with patient survival and likelihood of receiving an intestinal transplant in a contemporary cohort of children with intestinal failure. Methods This was an analysis of a multicenter cohort study with data collected from chart review conducted by the Pediatric Intestinal Consortium (PIFCon). Entry criteria included infants < 12 mo receiving parenteral nutrition (PN) for > 60 continuous days and followed for at least 2 years. Outcomes included death and intestinal transplant (ITx). Race and ethnicity were recorded as they were in the medical record. For purposes of statistical comparisons and regression modeling, categories of race were consolidated into “white” and “non-white” children. Results Of 272 subjects enrolled, 204 white and 46 non-white children were available for analysis. The 48 month cumulative incidence probability (CIP) of death without ITx was 0.40 for non-white and 0.16 for white children (p<0.001); the CIP of ITx was 0.07 for non-white vs 0.31 for white children (p=0.003). The associations between race and outcomes remained after accounting for low-birth weight, diagnosis, and being seen at a transplant center. Conclusion Race is associated with death and receiving an ITx in a large cohort of children with intestinal failure. This study highlights the need to investigate reasons for this apparent racial disparity in outcome among children with intestinal failure. PMID:24918984

  20. Neutrophil motility in extracellular matrix gels: mesh size and adhesion affect speed of migration.

    PubMed Central

    Kuntz, R M; Saltzman, W M

    1997-01-01

    Polymorphonuclear leukocyte (PMN) migration through tissue extracellular space is an essential step in the inflammatory response, but little is known about the factors influencing PMN migration through gels of extracellular matrix (ECM). In this study, PMN migration within reconstituted gels containing collagen type I or collagen type I supplemented with laminin, fibronectin, or heparin was measured by quantitative direct visualization, resulting in a random motility coefficient (mum a quantitative index for rate of cell dispersion) for the migrating cell population. The random motility coefficient in unsupplemented collagen (0.4 mg/ml) gels was approximately 9 x 10(-9) cm2/s. Supplementing gels with heparin or fibronectin produced a significant decrease in mu, even at the lowest concentrations studied (1 microgram/ml fibronectin or 0.4 microgram/ml heparin). At least 100 micrograms/ml of laminin, or 20% of the total gel protein, was required to produce a similar decrease in mu. Scanning electron microscopy revealed two different gel morphologies: laminin or fibronectin appeared to coat the 150-nm collagen fibers whereas heparin appeared to induce fiber bundle formation and, therefore, larger interstitial spaces. The decrease in mu observed in heparin-supplemented gels correlated with the increased mesh size of the fiber network, but the difference observed in mu for fibronectin- and laminin-supplemented gels did not correlate with either mesh size or the mechanical properties of the gel, as determined by rheological measurements. However, PMNs adhered to fibronectin-coated surfaces in greater numbers than to collagen- or laminin-coated surfaces, suggesting that changes in cell adhesion to protein fibers can also produce significant changes in cell motility within an ECM gel. Images FIGURE 2 FIGURE 3 FIGURE 9 PMID:9138592

  1. Polyphenols from olive mill waste affect biofilm formation and motility in Escherichia coli K-12

    PubMed Central

    Carraro, Lisa; Fasolato, Luca; Montemurro, Filomena; Martino, Maria Elena; Balzan, Stefania; Servili, Maurizio; Novelli, Enrico; Cardazzo, Barbara

    2014-01-01

    Olive mill wastes are sources of phenolic compounds with a wide array of biological activities, including antimicrobial effects. A potential option for bioremediation to overcome ecological problems is the reutilization of these natural compounds in food production. The aim of this work was to gain a better understanding of the antimicrobial mode of action of a phenols extract from olive vegetation water (PEOVW) at molecular level by studying Escherichia coli as a model microorganism. Genome-wide transcriptional analysis was performed on E. coli K-12 exposed to PEOVW. The repression of genes for flagellar synthesis and the involvement of genes linked to biofilm formation and stress response were observed. Sub-inhibitory concentrations of PEOVW significantly decreased biofilm formation, swarming and swimming motility, thus confirming the gene expression data. This study provides interesting insights on the molecular action of PEOVW on E. coli K-12. Given these anti-biofilm properties and considering that biofilm formation is a serious problem for the food industry and human health, PEOVW has proved to be a high-value natural product. Olive mill wastes are sources of phenolic compounds with a wide array of biological activities, including antimicrobial effects. Genome-wide transcriptional analysis was performed on E. coli K-12 exposed to phenols extract from olive vegetation water (PEOVW). Sub-inhibitory concentrations of PEOVW significantly decreased biofilm formation, swarming and swimming motility. Given these anti-biofilm properties PEOVW has proved to be a high-value natural product. PMID:24628798

  2. Effects of early enteral nutrition on the gastrointestinal motility and intestinal mucosal barrier of patients with burn-induced invasive fungal infection

    PubMed Central

    Zhang, Yu; Gu, Fang; Wang, Fengxian; Zhang, Yuanda

    2016-01-01

    Objective: To evaluate the effects of early enteral nutrition on the gastrointestinal motility and intestinal mucosal barrier of patients with burn-induced invasive fungal infection. Methods: A total of 120 patients with burn-induced invasive fungal infection were randomly divided into an early enteral nutrition (EN) group and a parenteral nutrition (PN) group (n=60). The patients were given nutritional support intervention for 14 days, and the expression levels of serum transferrin, albumin, total protein, endotoxin, D-lactic acid and inflammatory cytokines were detected on the 1st, 7th and 14th days respectively. Results: As the treatment progressed, the levels of serum transferrin, albumin and total protein of the EN group were significantly higher than those of the PN group (P<0.05), while the levels of serum endotoxin and D-lactic acid of the form group were significantly lower (P<0.05). After treatment, the expression levels of IL-6 and TNF-α were decreased in the EN group, which were significantly different from those of the PN group (P<0.05). During treatment, the incidence rates of complications such as abdominal distension, diarrhea, sepsis, nausea, vomiting and gastric retention were similar. The mean healing time of wound surface was 9.34±0.78 days in the EN group and 12.46±2.19 days in the PN group, i.e. such time of the former was significantly shorter than that of the latter (P<0.05). Conclusion: Treating patients having burn-induced invasive fungal infection by early enteral nutrition support with arginine can safely alleviate malnutrition and stress reaction, strengthen cellular immune function and promote wound healing, thereby facilitating the recovery of gastrointestinal motility and the function of intestinal mucosal barrier. PMID:27375697

  3. UV-B affects photosynthesis, ROS production and motility of the freshwater flagellate, Euglena agilis Carter.

    PubMed

    Kottuparambil, Sreejith; Shin, Woongghi; Brown, Murray T; Han, Taejun

    2012-10-15

    The effects of ultraviolet B (UV-B; 295-320 nm) radiation on certain vital physiological (photosynthesis), biochemical (production of reactive oxygen species - ROS) and behavioral (motility and orientation) characteristics were investigated in the unicellular photoautotroph, Euglena agilis Carter. The photosynthetic performance of E. agilis was recorded after exposure of between 15 and 60 min followed by a period of recovery lasting 6-24h under dim light (5-10 μmol photons m(-2) s(-1)). The maximum quantum yield of PS II (F(v)/F(m)) was reduced to 65% and 14% of initial values immediately following 15 and 30 min UV-B exposure, but recovered to 100 and 86% of the initials, respectively. Values of rETR(max) in E. agilis exposed to 15 min UV-B were similar to those of the initials, but a 30 min UV exposure resulted in 75% reduction of rETR(max) with only a 43% recovery as compared with the initial after 24h recovery. After a 60 min UV-B exposure, there were no Chl a fluorescence signals, and hence no F(v)/F(m) or rETR(max). A UV dose-dependent increase in DCFH-DA fluorescence was found in E. agilis cells, reflecting an increase in ROS production. After exposures to UV-B for between 15 and 60 min, the percentages of motile cells in the population decreased to 76, 39 and 15%, respectively. Following 24h in dim light, the percentage of motile cells increased to between 66% and 95% of the initial value. The velocity of non-irradiated cells was 60 μm s(-1), which decreased to 16-35 μm s(-1) immediately following exposure for 15-60 min. After periods of time in dim light (6, 12 and 24h) velocities had recovered to between 44 and 81% of the initial value. In untreated controls, the r-value was 0.23, indicating random movement of E. agilis, but it increased to 0.35 and 0.72 after exposure to UV-B for 30 and 60 min, respectively. There was a tendency towards vertical downward movement of cells proportional to the duration of exposure. The compactness of E. agilis decreased

  4. Intestine.

    PubMed

    Smith, J M; Skeans, M A; Horslen, S P; Edwards, E B; Harper, A M; Snyder, J J; Israni, A K; Kasiske, B L

    2016-01-01

    Intestine and intestine-liver transplant plays an important role in the treatment of intestinal failure, despite decreased morbidity associated with parenteral nutrition. In 2014, 210 new patients were added to the intestine transplant waiting list. Among prevalent patients on the list at the end of 2014, 65% were waiting for an intestine transplant and 35% were waiting for an intestine-liver transplant. The pretransplant mortality rate decreased dramatically over time for all age groups. Pretransplant mortality was highest for adult candidates, at 22.1 per 100 waitlist years compared with less than 3 per 100 waitlist years for pediatric candidates, and notably higher for candidates for intestine-liver transplant than for candidates for intestine transplant without a liver. Numbers of intestine transplants without a liver increased from a low of 51 in 2013 to 67 in 2014. Intestine-liver transplants increased from a low of 44 in 2012 to 72 in 2014. Short-gut syndrome (congenital and other) was the main cause of disease leading to both intestine and intestine-liver transplant. Graft survival improved over the past decade. Patient survival was lowest for adult intestine-liver recipients and highest for pediatric intestine recipients.

  5. Deiodinase knockdown during early zebrafish development affects growth, development, energy metabolism, motility and phototransduction.

    PubMed

    Bagci, Enise; Heijlen, Marjolein; Vergauwen, Lucia; Hagenaars, An; Houbrechts, Anne M; Esguerra, Camila V; Blust, Ronny; Darras, Veerle M; Knapen, Dries

    2015-01-01

    Thyroid hormone (TH) balance is essential for vertebrate development. Deiodinase type 1 (D1) and type 2 (D2) increase and deiodinase type 3 (D3) decreases local intracellular levels of T3, the most important active TH. The role of deiodinase-mediated TH effects in early vertebrate development is only partially understood. Therefore, we investigated the role of deiodinases during early development of zebrafish until 96 hours post fertilization at the level of the transcriptome (microarray), biochemistry, morphology and physiology using morpholino (MO) knockdown. Knockdown of D1+D2 (D1D2MO) and knockdown of D3 (D3MO) both resulted in transcriptional regulation of energy metabolism and (muscle) development in abdomen and tail, together with reduced growth, impaired swim bladder inflation, reduced protein content and reduced motility. The reduced growth and impaired swim bladder inflation in D1D2MO could be due to lower levels of T3 which is known to drive growth and development. The pronounced upregulation of a large number of transcripts coding for key proteins in ATP-producing pathways in D1D2MO could reflect a compensatory response to a decreased metabolic rate, also typically linked to hypothyroidism. Compared to D1D2MO, the effects were more pronounced or more frequent in D3MO, in which hyperthyroidism is expected. More specifically, increased heart rate, delayed hatching and increased carbohydrate content were observed only in D3MO. An increase of the metabolic rate, a decrease of the metabolic efficiency and a stimulation of gluconeogenesis using amino acids as substrates may have been involved in the observed reduced protein content, growth and motility in D3MO larvae. Furthermore, expression of transcripts involved in purine metabolism coupled to vision was decreased in both knockdown conditions, suggesting that both may impair vision. This study provides new insights, not only into the role of deiodinases, but also into the importance of a correct TH balance

  6. Deiodinase Knockdown during Early Zebrafish Development Affects Growth, Development, Energy Metabolism, Motility and Phototransduction

    PubMed Central

    Bagci, Enise; Heijlen, Marjolein; Vergauwen, Lucia; Hagenaars, An; Houbrechts, Anne M.; Esguerra, Camila V.; Blust, Ronny; Darras, Veerle M.; Knapen, Dries

    2015-01-01

    Thyroid hormone (TH) balance is essential for vertebrate development. Deiodinase type 1 (D1) and type 2 (D2) increase and deiodinase type 3 (D3) decreases local intracellular levels of T3, the most important active TH. The role of deiodinase-mediated TH effects in early vertebrate development is only partially understood. Therefore, we investigated the role of deiodinases during early development of zebrafish until 96 hours post fertilization at the level of the transcriptome (microarray), biochemistry, morphology and physiology using morpholino (MO) knockdown. Knockdown of D1+D2 (D1D2MO) and knockdown of D3 (D3MO) both resulted in transcriptional regulation of energy metabolism and (muscle) development in abdomen and tail, together with reduced growth, impaired swim bladder inflation, reduced protein content and reduced motility. The reduced growth and impaired swim bladder inflation in D1D2MO could be due to lower levels of T3 which is known to drive growth and development. The pronounced upregulation of a large number of transcripts coding for key proteins in ATP-producing pathways in D1D2MO could reflect a compensatory response to a decreased metabolic rate, also typically linked to hypothyroidism. Compared to D1D2MO, the effects were more pronounced or more frequent in D3MO, in which hyperthyroidism is expected. More specifically, increased heart rate, delayed hatching and increased carbohydrate content were observed only in D3MO. An increase of the metabolic rate, a decrease of the metabolic efficiency and a stimulation of gluconeogenesis using amino acids as substrates may have been involved in the observed reduced protein content, growth and motility in D3MO larvae. Furthermore, expression of transcripts involved in purine metabolism coupled to vision was decreased in both knockdown conditions, suggesting that both may impair vision. This study provides new insights, not only into the role of deiodinases, but also into the importance of a correct TH balance

  7. The post-translational modification of the Clostridium difficile flagellin affects motility, cell surface properties and virulence

    PubMed Central

    Faulds-Pain, Alexandra; Twine, Susan M; Vinogradov, Evgeny; Strong, Philippa C R; Dell, Anne; Buckley, Anthony M; Douce, Gillian R; Valiente, Esmeralda; Logan, Susan M; Wren, Brendan W

    2014-01-01

    Clostridium difficile is a prominent nosocomial pathogen, proliferating and causing enteric disease in individuals with a compromised gut microflora. We characterized the post-translational modification of flagellin in C. difficile 630. The structure of the modification was solved by nuclear magnetic resonance and shown to contain an N-acetylglucosamine substituted with a phosphorylated N-methyl-l-threonine. A reverse genetics approach investigated the function of the putative four-gene modification locus. All mutants were found to have truncated glycan structures by LC-MS/MS, taking into account bioinformatic analysis, we propose that the open reading frame CD0241 encodes a kinase involved in the transfer of the phosphate to the threonine, the CD0242 protein catalyses the addition of the phosphothreonine to the N-acetylglucosamine moiety and CD0243 transfers the methyl group to the threonine. Some mutations affected motility and caused cells to aggregate to each other and abiotic surfaces. Altering the structure of the flagellin modification impacted on colonization and disease recurrence in a murine model of infection, showing that alterations in the surface architecture of C. difficile vegetative cells can play a significant role in disease. We show that motility is not a requirement for colonization, but that colonization was compromised when the glycan structure was incomplete. PMID:25135277

  8. The post-translational modification of the Clostridium difficile flagellin affects motility, cell surface properties and virulence.

    PubMed

    Faulds-Pain, Alexandra; Twine, Susan M; Vinogradov, Evgeny; Strong, Philippa C R; Dell, Anne; Buckley, Anthony M; Douce, Gillian R; Valiente, Esmeralda; Logan, Susan M; Wren, Brendan W

    2014-10-01

    Clostridium difficile is a prominent nosocomial pathogen, proliferating and causing enteric disease in individuals with a compromised gut microflora. We characterized the post-translational modification of flagellin in C. difficile 630. The structure of the modification was solved by nuclear magnetic resonance and shown to contain an N-acetylglucosamine substituted with a phosphorylated N-methyl-l-threonine. A reverse genetics approach investigated the function of the putative four-gene modification locus. All mutants were found to have truncated glycan structures by LC-MS/MS, taking into account bioinformatic analysis, we propose that the open reading frame CD0241 encodes a kinase involved in the transfer of the phosphate to the threonine, the CD0242 protein catalyses the addition of the phosphothreonine to the N-acetylglucosamine moiety and CD0243 transfers the methyl group to the threonine. Some mutations affected motility and caused cells to aggregate to each other and abiotic surfaces. Altering the structure of the flagellin modification impacted on colonization and disease recurrence in a murine model of infection, showing that alterations in the surface architecture of C. difficile vegetative cells can play a significant role in disease. We show that motility is not a requirement for colonization, but that colonization was compromised when the glycan structure was incomplete. PMID:25135277

  9. Polyphenols from olive mill waste affect biofilm formation and motility in Escherichia coli K-12.

    PubMed

    Carraro, Lisa; Fasolato, Luca; Montemurro, Filomena; Martino, Maria Elena; Balzan, Stefania; Servili, Maurizio; Novelli, Enrico; Cardazzo, Barbara

    2014-05-01

    Olive mill wastes are sources of phenolic compounds with a wide array of biological activities, including antimicrobial effects. A potential option for bioremediation to overcome ecological problems is the reutilization of these natural compounds in food production. The aim of this work was to gain a better understanding of the antimicrobial mode of action of a phenols extract from olive vegetation water (PEOVW) at molecular level by studying Escherichia coli as a model microorganism. Genome-wide transcriptional analysis was performed on E. coli K-12 exposed to PEOVW. The repression of genes for flagellar synthesis and the involvement of genes linked to biofilm formation and stress response were observed. Sub-inhibitory concentrations of PEOVW significantly decreased biofilm formation, swarming and swimming motility, thus confirming the gene expression data. This study provides interesting insights on the molecular action of PEOVW on E. coli K-12. Given these anti-biofilm properties and considering that biofilm formation is a serious problem for the food industry and human health, PEOVW has proved to be a high-value natural product.

  10. Polyglycylation of Tubulin Is Essential and Affects Cell Motility and Division in Tetrahymena thermophila

    PubMed Central

    Xia, Lu; Hai, Bing; Gao, Yan; Burnette, Dylan; Thazhath, Rupal; Duan, Jianming; Bré, Marie-Helene; Levilliers, Nicolette; Gorovsky, Martin A.; Gaertig, Jacek

    2000-01-01

    We analyzed the role of tubulin polyglycylation in Tetrahymena thermophila using in vivo mutagenesis and immunochemical analysis with modification-specific antibodies. Three and five polyglycylation sites were identified at glutamic acids near the COOH termini of α- and β-tubulin, respectively. Mutants lacking all polyglycylation sites on α-tubulin have normal phenotype, whereas similar sites on β-tubulin are essential. A viable mutant with three mutated sites in β-tubulin showed reduced tubulin glycylation, slow growth and motility, and defects in cytokinesis. Cells in which all five polyglycylation sites on β-tubulin were mutated were viable if they were cotransformed with an α-tubulin gene whose COOH terminus was replaced by the wild-type COOH terminus of β-tubulin. In this double mutant, β-tubulin lacked detectable polyglycylation, while the α-β tubulin chimera was hyperglycylated compared with α-tubulin in wild-type cells. Thus, the essential function of polyglycylation of the COOH terminus of β-tubulin can be transferred to α-tubulin, indicating it is the total amount of polyglycylation on both α- and β-tubulin that is essential for survival. PMID:10831613

  11. Protein acetylation affects acetate metabolism, motility and acid stress response in Escherichia coli

    PubMed Central

    Castaño-Cerezo, Sara; Bernal, Vicente; Post, Harm; Fuhrer, Tobias; Cappadona, Salvatore; Sánchez-Díaz, Nerea C; Sauer, Uwe; Heck, Albert JR; Altelaar, AF Maarten; Cánovas, Manuel

    2014-01-01

    Although protein acetylation is widely observed, it has been associated with few specific regulatory functions making it poorly understood. To interrogate its functionality, we analyzed the acetylome in Escherichia coli knockout mutants of cobB, the only known sirtuin-like deacetylase, and patZ, the best-known protein acetyltransferase. For four growth conditions, more than 2,000 unique acetylated peptides, belonging to 809 proteins, were identified and differentially quantified. Nearly 65% of these proteins are related to metabolism. The global activity of CobB contributes to the deacetylation of a large number of substrates and has a major impact on physiology. Apart from the regulation of acetyl-CoA synthetase, we found that CobB-controlled acetylation of isocitrate lyase contributes to the fine-tuning of the glyoxylate shunt. Acetylation of the transcription factor RcsB prevents DNA binding, activating flagella biosynthesis and motility, and increases acid stress susceptibility. Surprisingly, deletion of patZ increased acetylation in acetate cultures, which suggests that it regulates the levels of acetylating agents. The results presented offer new insights into functional roles of protein acetylation in metabolic fitness and global cell regulation. PMID:25518064

  12. Enteral leptin administration affects intestinal autophagy in suckling piglets.

    PubMed

    Słupecka, M; Woliński, J; Gajewska, M; Pierzynowski, S G

    2014-01-01

    Leptin has been shown to play an integral role in the endocrine regulation of metabolism. Moreover, a substantial amount of this peptide has been found in colostrum and milk. The aim of the study was to investigate the effects of exogenous leptin, administered intragastrically, on the process of autophagy and the changes in cell hyperplasia and hypertrophy in the small intestine mucosa. Three groups (n = 6) of neonatal piglets were used in the study. The pigs were fed either by their sows (sow-reared piglets) or with only milk formula, or with milk formula together with leptin administered via a stomach tube (10 μg/kg BW) every 8 h for 6 d. We have shown that pure milk formula feeding significantly elevates (P < 0.05) autophagy compared with that observed in sow-reared piglets. Compared with the control group, feeding milk formula supplemented with leptin resulted in a significant decrease (P < 0.05) in immunodetection of microtubule-associated protein 1 light chain 3, as well as significantly accelerated epithelial cell renewal (P < 0.05). We demonstrated that autophagy is involved in the remodeling of the small intestine mucosa and that leptin, when administered enterally, may be an important factor for its regulation.

  13. Factors affecting sperm motility. III. Influence of visible light and other electromagnetic radiations on human sperm velocity and survival.

    PubMed

    Makler, A; Tatcher, M; Vilensky, A; Brandes, J M

    1980-04-01

    Specimens of semen from fertile and infertile patients were exposed to different electromagnetic radiations, including visible light, ultraviolet (UV) light, x-rays, and high-frequency radio waves. Sperm motility was analyzed before, during, and after irradiation by the multiple exposure photography (MEP) method. No significant difference was found between controls and specimens exposed to various doses of visible and UV light and x-rays either immediately or several hours after exposure. In contrast to spermatozoa of other species that were reported to be adversely affected by visible and UV light and x-rays, human spermatozoa seem to be highly resistant to similar doses of these radiations. A deleterious influence was observed when high-frequency radio waves were applied to human spermatozoa. This may be attributed to an intracellular diathermic effect. The informative value of this study in relation to routine semen analyses and experimental studies in the physiology and comparative anatomy of spermatozoa is discussed.

  14. Total Glucosides of Paeony Promote Intestinal Motility in Slow Transit Constipation Rats through Amelioration of Interstitial Cells of Cajal

    PubMed Central

    Zhu, Feiye; Xu, Shan; Zhang, Yongsheng; Chen, Fangming; Ji, Jinjun; Xie, Guanqun

    2016-01-01

    Objectives Using an atropine-diphenoxylate-induced slow transit constipation (STC) model, this study explored the effects of the total glucosides of paeony (TGP) in the treatment of STC and the possible mechanisms. Study Design A prospective experimental animal study. Methods The constipation model was set up in rats with an oral gavage of atropine-diphenoxylate and then treated with the TGP. The volume and moisture content of the faeces were observed and the intestinal kinetic power was evaluated. Meanwhile, the colorimetric method and enzyme linked immunosorbent assay (ELISA) were employed to determine the changes of nitric oxide (NO), nitric oxide synthase (NOS), vasoative intestinal peptide (VIP) and the P substance (SP) in the serum, respectively. The protein expressions of c-kit and stem cell factor (SCF) were assessed by immunohistochemical analysis and western blot, respectively, and the mRNA level of c-kit was measured by a reverse transcription polymerase chain reaction (RT-PCR). Results The TGP attenuated STC responses in terms of an increase in the fecal volume and moisture content, an enhancement of intestinal transit rate and the reduction of NO, NOS and VIP in the serum. In addition, the c-kit, a labeling of interstitial cells of Cajal (ICC) increased at both protein and mRNA levels. SCF, which serves as a ligand of c-kit also increased at protein level. Conclusion The analysis of our data indicated that the TGP could obviously attenuate STC through improving the function of ICC and blocking the inhibitory neurotransmitters such as NO, NOS and VIP. PMID:27478893

  15. Elevated motility-related transmucosal potential difference in the upper small intestine in the irritable bowel syndrome.

    PubMed

    Larsson, M H; Simrén, M; Thomas, E A; Bornstein, J C; Lindström, E; Sjövall, H

    2007-10-01

    The pathophysiology of irritable bowel syndrome (IBS) is complex and incompletely known. Very little has been studied regarding the role of submucous neuronal activity. We therefore measured small intestinal transmural potential difference (PD, reflecting mainly electrogenic chloride secretion), and its linkage with fasting motor activity [migrating motor complex (MMC)] in controls (n = 16) and patients with IBS [n = 23, 14 diarrhoea predominant (d-IBS) and nine constipation predominant (c-IBS)]. Transmural-PD and its relation to MMC phase III was measured by modified multilumen manometry for 3 h in the fasting state using one jejunal and one duodenal infusion line as flowing electrodes. The amplitude and duration of motor phase III was similar in controls and IBS patients, but the propagation speed of phase III was higher in IBS patients. In IBS patients, maximal PD during MMC phase III was significantly elevated in both the duodenum and jejunum (P < 0.05) and the PD decline after phase III was significantly prolonged in the jejunum (P < 0.01). The PD elevation was seen in both duodenum and jejunum in d-IBS patients, but only in the jejunum in the c-IBS patients. On the basis of previous modelling studies, we propose that the enhanced secretion may reflect disturbed enteric network behaviour in some patients with IBS.

  16. Daily exposure to summer temperatures affects the motile subpopulation structure of epididymal sperm cells but not male fertility in an in vivo rabbit model.

    PubMed

    Maya-Soriano, M J; Taberner, E; Sabés-Alsina, M; Ramon, J; Rafel, O; Tusell, L; Piles, M; López-Béjar, M

    2015-08-01

    High temperatures have negative effects on sperm quality leading to temporary or permanent sterility. The aim of the study was to assess the effect of long exposure to summer circadian heat stress cycles on sperm parameters and the motile subpopulation structure of epididymal sperm cells from rabbit bucks. Twelve White New Zealand rabbit bucks were exposed to a daily constant temperature of the thermoneutral zone (from 18 °C to 22 °C; control group) or exposed to a summer circadian heat stress cycles (30 °C, 3 h/day; heat stress group). Spermatozoa were flushed from the epididymis and assessed for sperm quality parameters at recovery. Sperm total motility and progressivity were negatively affected by high temperatures (P < 0.05), as were also specific motility parameters (curvilinear velocity, linear velocity, mean velocity, straightness coefficient, linearity coefficient, wobble coefficient, and frequency of head displacement; P < 0.05, but not the mean amplitude of lateral head displacement). Heat stress significantly increased the percentage of less-motile sperm subpopulations, although the percentage of the high-motile subpopulation was maintained, which is consistent with the fact that no effect was detected on fertility rates. However, prolificacy was reduced in females submitted to heat stress when inseminated by control bucks. In conclusion, our results suggest that environmental high temperatures are linked to changes in the proportion of motile sperm subpopulations of the epididymis, although fertility is still preserved despite the detrimental effects of heat stress. On the other hand, prolificacy seems to be affected by the negative effects of high temperatures, especially by altering female reproduction. PMID:25944779

  17. Daily exposure to summer temperatures affects the motile subpopulation structure of epididymal sperm cells but not male fertility in an in vivo rabbit model.

    PubMed

    Maya-Soriano, M J; Taberner, E; Sabés-Alsina, M; Ramon, J; Rafel, O; Tusell, L; Piles, M; López-Béjar, M

    2015-08-01

    High temperatures have negative effects on sperm quality leading to temporary or permanent sterility. The aim of the study was to assess the effect of long exposure to summer circadian heat stress cycles on sperm parameters and the motile subpopulation structure of epididymal sperm cells from rabbit bucks. Twelve White New Zealand rabbit bucks were exposed to a daily constant temperature of the thermoneutral zone (from 18 °C to 22 °C; control group) or exposed to a summer circadian heat stress cycles (30 °C, 3 h/day; heat stress group). Spermatozoa were flushed from the epididymis and assessed for sperm quality parameters at recovery. Sperm total motility and progressivity were negatively affected by high temperatures (P < 0.05), as were also specific motility parameters (curvilinear velocity, linear velocity, mean velocity, straightness coefficient, linearity coefficient, wobble coefficient, and frequency of head displacement; P < 0.05, but not the mean amplitude of lateral head displacement). Heat stress significantly increased the percentage of less-motile sperm subpopulations, although the percentage of the high-motile subpopulation was maintained, which is consistent with the fact that no effect was detected on fertility rates. However, prolificacy was reduced in females submitted to heat stress when inseminated by control bucks. In conclusion, our results suggest that environmental high temperatures are linked to changes in the proportion of motile sperm subpopulations of the epididymis, although fertility is still preserved despite the detrimental effects of heat stress. On the other hand, prolificacy seems to be affected by the negative effects of high temperatures, especially by altering female reproduction.

  18. Osmolality and composition of the activating solution affects motility of fresh and frozen Prochilodus lineatus sperm differently.

    PubMed

    Viveiros, Ana T M; Leal, Marcelo C; França, Thales S; Almeida, Izabella L G; Isaú, Ziara A

    2016-10-01

    Osmolality and composition of the activating solution on motility of fresh and frozen Prochilodus lineatus sperm were evaluated. Sperm was triggered in 11 solutions prepared with reverse osmosis (RO) water (∼0mOsmkg(-1)), and glucose or NaCl adjusted to 50, 100, 150, 200 and 250mOsmkg(-1). Sperm motility rate and velocities (curvilinear=VCL, among others) were evaluated in fresh sperm at 10, 30 and 50s post-activation (spa), and in frozen sperm at 10 spa only. Sperm was frozen under a standardized methodology for this species. Fresh sperm motility was higher in samples triggered in RO (91%), in glucose at all osmolalities (90-92%) and in 50-150mOsmkg(-1) NaCl (88-91%) than that in 200-250mOsmkg(-1) NaCl (74-80%). Motility decreased (P<0.05) as a function of time after activation in samples activated in RO and in NaCl but not in glucose. Samples activated in 100-250mOsmkg(-1) glucose yielded motility above 80%, at 50 spa. Curvilinear velocity was higher (P<0.05) in glucose-activated samples (322-357μms(-1)) compared to that activated in NaCl (192-283μms(-1)) and in RO (298μms(-1)). Frozen sperm motility and velocities were similar when triggered in RO, glucose or NaCl and were higher at 0-150 mOsm kg(-1) (69-78% motility; 163-208μms(-1) VCL) than at 200-250mOsmkg(-1) (34-59% motility; 127-168μms(-1) VCL). High sperm motility with fast velocity for a long period is achieved at 100-150mOsmkg(-1), in glucose solution for fresh sperm and in glucose or NaCl for frozen sperm. PMID:27601320

  19. Protective Effect of Proteinase-Activated Receptor 2 Activation on Motility Impairment and Tissue Damage Induced by Intestinal Ischemia/Reperfusion in Rodents

    PubMed Central

    Cattaruzza, Fiore; Cenac, Nicolas; Barocelli, Elisabetta; Impicciatore, Mariannina; Hyun, Eric; Vergnolle, Nathalie; Sternini, Catia

    2006-01-01

    We hypothesized that proteinase-activated receptor-2 (PAR2) modulates intestinal injuries induced by ischemia/reperfusion. Ischemia (1 hour) plus reperfusion (6 hours) significantly delayed gastrointestinal transit (GIT) compared with sham operation. Intraduodenal injection of PAR2-activating peptide SLIGRL-NH2 significantly accelerated transit in ischemia/reperfusion but not in sham-operated rats. GIT was significantly delayed in ischemia/reperfusion and sham-operated PAR2−/− mice compared with PAR2+/+. SLIGRL-NH2 significantly accelerated transit in ischemia/reperfusion in PAR2+/+ but not in PAR2−/− mice. Prevention of mast cell degranulation with cromolyn, ablation of visceral afferents with capsaicin, and antagonism of calcitonin gene-related peptide (CGRP) and neurokinin-1 receptors with CGRP8–37 and RP67580, respectively, abolished the SLIGRL-NH2-induced stimulatory effect on transit in ischemia/reperfusion. Tissue damage was significantly reduced by SLIGRL-NH2; this effect was not observed in cromolyn-, capsaicin-, or RP67580-treated rats but was detected following CGRP8–37. Intestinal PAR2 mRNA levels were not affected by SLIGRL-NH2 in ischemia/reperfusion. We propose that PAR2 modulates GIT and tissue damage in intestinal ischemia/reperfusion by a mechanism dependent on mast cells and visceral afferents. PAR2 effect on transit might be mediated by CGRP and substance P, whereas the effect on tissue damage appears to involve substance P but not CGRP. PAR2 might be a signaling system in the neuroimmune communication in intestinal ischemia/reperfusion. PMID:16816371

  20. Consumption of Oxidized Soybean Oil Increased Intestinal Oxidative Stress and Affected Intestinal Immune Variables in Yellow-feathered Broilers.

    PubMed

    Liang, Fangfang; Jiang, Shouqun; Mo, Yi; Zhou, Guilian; Yang, Lin

    2015-08-01

    This study investigated the effect of oxidized soybean oil in the diet of young chickens on growth performance and intestinal oxidative stress, and indices of intestinal immune function. Corn-soybean-based diets containing 2% mixtures of fresh and oxidized soybean oil provided 6 levels (0.15, 1.01, 3.14, 4.95, 7.05, and 8.97 meqO2/kg) of peroxide value (POV) in the diets. Each dietary treatment, fed for 22 d, had 6 replicates, each containing 30 birds (n = 1,080). Increasing POV levels reduced average daily feed intake (ADFI) of the broilers during d 1 to 10, body weight and average daily gain at d 22 but did not affect overall ADFI. Concentrations of malondialdehyde (MDA) increased in plasma and jejunum as POV increased but total antioxidative capacity (T-AOC) declined in plasma and jejunum. Catalase (CAT) activity declined in plasma and jejunum as did plasma glutathione S-transferase (GST). Effects were apparent at POV exceeding 3.14 meqO2/kg for early ADFI and MDA in jejunum, and POV exceeding 1.01 meqO2/kg for CAT in plasma and jejunum, GST in plasma and T-AOC in jejunum. Relative jejunal abundance of nuclear factor kappa B (NF-κB) P50 and NF-κB P65 increased as dietary POV increased. Increasing POV levels reduced the jejunal concentrations of secretory immunoglobulin A and cluster of differentiation (CD) 4 and CD8 molecules with differences from controls apparent at dietary POV of 3.14 to 4.95 meqO2/kg. These findings indicated that growth performance, feed intake, and the local immune system of the small intestine were compromised by oxidative stress when young broilers were fed moderately oxidized soybean oil.

  1. Consumption of Oxidized Soybean Oil Increased Intestinal Oxidative Stress and Affected Intestinal Immune Variables in Yellow-feathered Broilers

    PubMed Central

    Liang, Fangfang; Jiang, Shouqun; Mo, Yi; Zhou, Guilian; Yang, Lin

    2015-01-01

    This study investigated the effect of oxidized soybean oil in the diet of young chickens on growth performance and intestinal oxidative stress, and indices of intestinal immune function. Corn-soybean-based diets containing 2% mixtures of fresh and oxidized soybean oil provided 6 levels (0.15, 1.01, 3.14, 4.95, 7.05, and 8.97 meqO2/kg) of peroxide value (POV) in the diets. Each dietary treatment, fed for 22 d, had 6 replicates, each containing 30 birds (n = 1,080). Increasing POV levels reduced average daily feed intake (ADFI) of the broilers during d 1 to 10, body weight and average daily gain at d 22 but did not affect overall ADFI. Concentrations of malondialdehyde (MDA) increased in plasma and jejunum as POV increased but total antioxidative capacity (T-AOC) declined in plasma and jejunum. Catalase (CAT) activity declined in plasma and jejunum as did plasma glutathione S-transferase (GST). Effects were apparent at POV exceeding 3.14 meqO2/kg for early ADFI and MDA in jejunum, and POV exceeding 1.01 meqO2/kg for CAT in plasma and jejunum, GST in plasma and T-AOC in jejunum. Relative jejunal abundance of nuclear factor kappa B (NF-κB) P50 and NF-κB P65 increased as dietary POV increased. Increasing POV levels reduced the jejunal concentrations of secretory immunoglobulin A and cluster of differentiation (CD) 4 and CD8 molecules with differences from controls apparent at dietary POV of 3.14 to 4.95 meqO2/kg. These findings indicated that growth performance, feed intake, and the local immune system of the small intestine were compromised by oxidative stress when young broilers were fed moderately oxidized soybean oil. PMID:26104529

  2. Xylitol Affects the Intestinal Microbiota and Metabolism of Daidzein in Adult Male Mice

    PubMed Central

    Tamura, Motoi; Hoshi, Chigusa; Hori, Sachiko

    2013-01-01

    This study examined the effects of xylitol on mouse intestinal microbiota and urinary isoflavonoids. Xylitol is classified as a sugar alcohol and used as a food additive. The intestinal microbiota seems to play an important role in isoflavone metabolism. Xylitol feeding appears to affect the gut microbiota. We hypothesized that dietary xylitol changes intestinal microbiota and, therefore, the metabolism of isoflavonoids in mice. Male mice were randomly divided into two groups: those fed a 0.05% daidzein with 5% xylitol diet (XD group) and those fed a 0.05% daidzein-containing control diet (CD group) for 28 days. Plasma total cholesterol concentrations were significantly lower in the XD group than in the CD group (p < 0.05). Urinary amounts of equol were significantly higher in the XD group than in the CD group (p < 0.05). The fecal lipid contents (% dry weight) were significantly greater in the XD group than in the CD group (p < 0.01). The cecal microbiota differed between the two dietary groups. The occupation ratios of Bacteroides were significantly greater in the CD than in the XD group (p < 0.05). This study suggests that xylitol has the potential to affect the metabolism of daidzein by altering the metabolic activity of the intestinal microbiota and/or gut environment. Given that equol affects bone health, dietary xylitol plus isoflavonoids may exert a favorable effect on bone health. PMID:24336061

  3. Xylitol affects the intestinal microbiota and metabolism of daidzein in adult male mice.

    PubMed

    Tamura, Motoi; Hoshi, Chigusa; Hori, Sachiko

    2013-12-10

    This study examined the effects of xylitol on mouse intestinal microbiota and urinary isoflavonoids. Xylitol is classified as a sugar alcohol and used as a food additive. The intestinal microbiota seems to play an important role in isoflavone metabolism. Xylitol feeding appears to affect the gut microbiota. We hypothesized that dietary xylitol changes intestinal microbiota and, therefore, the metabolism of isoflavonoids in mice. Male mice were randomly divided into two groups: those fed a 0.05% daidzein with 5% xylitol diet (XD group) and those fed a 0.05% daidzein-containing control diet (CD group) for 28 days. Plasma total cholesterol concentrations were significantly lower in the XD group than in the CD group (p < 0.05). Urinary amounts of equol were significantly higher in the XD group than in the CD group (p < 0.05). The fecal lipid contents (% dry weight) were significantly greater in the XD group than in the CD group (p < 0.01). The cecal microbiota differed between the two dietary groups. The occupation ratios of Bacteroides were significantly greater in the CD than in the XD group (p < 0.05). This study suggests that xylitol has the potential to affect the metabolism of daidzein by altering the metabolic activity of the intestinal microbiota and/or gut environment. Given that equol affects bone health, dietary xylitol plus isoflavonoids may exert a favorable effect on bone health.

  4. Low SP1 Expression Differentially Affects Intestinal-Type Compared with Diffuse-Type Gastric Adenocarcinoma

    PubMed Central

    Oh, Ensel; Erkin, Özgür Cem; Jung, Hun Soon; Cho, Mi-Hyun; Kwon, Mi Jeong; Chae, Seoung Wan; Kim, Seok-Hyung; Wang, Li-Hui; Park, Min-Jeong; Lee, Su-Yeon; Yang, Ho Bin; Jia, Lina; Choi, Yoon-La; Shin, Young Kee

    2013-01-01

    Specificity protein 1 (SP1) is an essential transcription factor that regulates multiple cancer-related genes. Because aberrant expression of SP1 is related to cancer development and progression, we focused on SP1 expression in gastric carcinoma and its correlation with disease outcomes. Although patient survival decreased as SP1 expression increased (P<0.05) in diffuse-type gastric cancer, the lack of SP1 expression in intestinal-type gastric cancer was significantly correlated with poor survival (P<0.05). The knockdown of SP1 in a high SP1-expressing intestinal-type gastric cell line, MKN28, increased migration and invasion but decreased proliferation. Microarray data in SP1 siRNA-transfected MKN28 revealed that the genes inhibiting migration were downregulated, whereas the genes negatively facilitating proliferation were increased. However, both migration and invasion were decreased by forced SP1 expression in a low SP1-expressing intestinal-type gastric cell line, AGS. Unlike the intestinal-type, in a high SP1-expressing diffuse-type gastric cell line, SNU484, migration and invasion were decreased by SP1 siRNA. In contrast to previous studies that did not identify differences between the 2 histological types, our results reveal that low expression of SP1 is involved in cancer progression and metastasis and differentially affects intestinal-type compared with diffuse-type gastric adenocarcinoma. PMID:23437057

  5. Deoxynivalenol affects in vitro intestinal epithelial cell barrier integrity through inhibition of protein synthesis

    SciTech Connect

    Van De Walle, Jacqueline; Sergent, Therese; Piront, Neil; Toussaint, Olivier; Schneider, Yves-Jacques; Larondelle, Yvan

    2010-06-15

    Deoxynivalenol (DON), one of the most common mycotoxin contaminants of raw and processed cereal food, adversely affects the gastrointestinal tract. Since DON acts as a protein synthesis inhibitor, the constantly renewing intestinal epithelium could be particularly sensitive to DON. We analyzed the toxicological effects of DON on intestinal epithelial protein synthesis and barrier integrity. Differentiated Caco-2 cells, as a widely used model of the human intestinal barrier, were exposed to realistic intestinal concentrations of DON (50, 500 and 5000 ng/ml) during 24 h. DON caused a concentration-dependent decrease in total protein content associated with a reduction in the incorporation of [{sup 3}H]-leucine, demonstrating its inhibitory effect on protein synthesis. DON simultaneously increased the paracellular permeability of the monolayer as reflected through a decreased transepithelial electrical resistance associated with an increased paracellular flux of the tracer [{sup 3}H]-mannitol. A concentration-dependent reduction in the expression level of the tight junction constituent claudin-4 was demonstrated by Western blot, which was not due to diminished transcription, increased degradation, or NF-{kappa}B, ERK or JNK activation, and was also observed for a tight junction independent protein, i.e. intestinal alkaline phosphatase. These results demonstrate a dual toxicological effect of DON on differentiated Caco-2 cells consisting in an inhibition of protein synthesis as well as an increase in monolayer permeability, and moreover suggest a possible link between them through diminished synthesis of the tight junction constituent claudin-4.

  6. [Obesity and gastrointestinal motility].

    PubMed

    Lee, Joon Seong

    2006-08-01

    Gastrointestinal (GI) motility has a crucial role in the food consumption, digestion and absorption, and also controls the appetite and satiety. In obese patients, various alterations of GI motility have been investigated. The prevalence of GERD and esophageal motor disorders in obese patients are higher than those of general population. Gastric emptying of solid food is generally accelerated and fasting gastric volume especially in distal stomach is larger in obese patients without change in accommodation. Contractile activity of small intestine in fasting period is more prominent, but orocecal transit is delayed. Autonomic dysfunction is frequently demonstrated in obese patients. These findings correspond with increased appetite and delayed satiety in obese patients, but causes or results have not been confirmed. Therapeutic interventions of these altered GI motility have been developed using botulinum toxin, gastric electrical stimulation in obese patients. Novel agents targeted for GI hormone modulation (such as ghrelin and leptin) need to be developed in the near future. PMID:16929152

  7. Modulation of intracellular calcium levels by calcium lactate affects colon cancer cell motility through calcium-dependent calpain.

    PubMed

    Sundaramoorthy, Pasupathi; Sim, Jae Jun; Jang, Yeong-Su; Mishra, Siddhartha Kumar; Jeong, Keun-Yeong; Mander, Poonam; Chul, Oh Byung; Shim, Won-Sik; Oh, Seung Hyun; Nam, Ky-Youb; Kim, Hwan Mook

    2015-01-01

    Cancer cell motility is a key phenomenon regulating invasion and metastasis. Focal adhesion kinase (FAK) plays a major role in cellular adhesion and metastasis of various cancers. The relationship between dietary supplementation of calcium and colon cancer has been extensively investigated. However, the effect of calcium (Ca2+) supplementation on calpain-FAK-motility is not clearly understood. We sought to identify the mechanism of FAK cleavage through Ca2+ bound lactate (CaLa), its downstream signaling and role in the motility of human colon cancer cells. We found that treating HCT116 and HT-29 cells with CaLa immediately increased the intracellular Ca2+ (iCa2+) levels for a prolonged period of time. Ca2+ influx induced cleavage of FAK into an N-terminal FAK (FERM domain) in a dose-dependent manner. Phosphorylated FAK (p-FAK) was also cleaved in to its p-N-terminal FAK. CaLa increased colon cancer cells motility. Calpeptin, a calpain inhibitor, reversed the effects of CaLa on FAK and pFAK cleavage in both cancer cell lines. The cleaved FAK translocates into the nucleus and modulates p53 stability through MDM2-associated ubiquitination. CaLa-induced Ca2+ influx increased the motility of colon cancer cells was mediated by calpain activity through FAK and pFAK protein destabilization. In conclusion, these results suggest that careful consideration may be given in deciding dietary Ca2+ supplementation to patient undergoing treatment for metastatic cancer.

  8. Fenugreek seed affects intestinal microbiota and immunological variables in piglets after weaning.

    PubMed

    Zentek, Jürgen; Gärtner, Stefanie; Tedin, Lydia; Männer, Klaus; Mader, Anneluise; Vahjen, Wilfried

    2013-03-14

    Fenugreek seed has been shown to affect the intestinal microbiota and immunological responses in animals. A feeding trial with male castrated piglets was performed over 28 d without or with the addition of 1·5 g fenugreek seeds/kg complete diet in ten and eleven piglets, weaned at 21 d. In the intestinal tract, pH, lactate and SCFA were measured as major bacterial metabolites. Immune cell phenotypes, phagocytic activity and lymphocyte proliferation after stimulation with pokeweed mitogen, concanavalin A and phytohaemagglutinin M were measured by flow cytometry. Health status and performance of the piglets were not affected by fenugreek. The pH in the caecum and colon were reduced compared with the control (P< 0·05). Higher concentrations of l-lactic acid were recorded in the small-intestinal digesta (average concentrations from the duodenum, jejunum and ileum; P< 0·05), while the concentrations of SCFA remained unchanged except an increase in n-butyric acid in colon contents (P< 0·05). The piglets fed the fenugreek diet had higher Lactobacillus and clostridium cluster I concentrations and lower Escherichia, Hafnia and Shigella concentrations in the small intestine. The addition of fenugreek increased the relative concentration of the γδ T-cell population (TCR1+CD8α-) in the blood with a simultaneous reduction of antigen-presenting cells (MHCII+CD5-) (P< 0·05). Proliferation rate and phagocytosis activity of monocytes were not affected by the additive. In conclusion, fenugreek seeds might be interesting as a feed ingredient for young piglets due to their effects on the intestinal microbiota and immunological variables. The impact on performance and animal health has to be further evaluated. PMID:22874597

  9. Fenugreek seed affects intestinal microbiota and immunological variables in piglets after weaning.

    PubMed

    Zentek, Jürgen; Gärtner, Stefanie; Tedin, Lydia; Männer, Klaus; Mader, Anneluise; Vahjen, Wilfried

    2013-03-14

    Fenugreek seed has been shown to affect the intestinal microbiota and immunological responses in animals. A feeding trial with male castrated piglets was performed over 28 d without or with the addition of 1·5 g fenugreek seeds/kg complete diet in ten and eleven piglets, weaned at 21 d. In the intestinal tract, pH, lactate and SCFA were measured as major bacterial metabolites. Immune cell phenotypes, phagocytic activity and lymphocyte proliferation after stimulation with pokeweed mitogen, concanavalin A and phytohaemagglutinin M were measured by flow cytometry. Health status and performance of the piglets were not affected by fenugreek. The pH in the caecum and colon were reduced compared with the control (P< 0·05). Higher concentrations of l-lactic acid were recorded in the small-intestinal digesta (average concentrations from the duodenum, jejunum and ileum; P< 0·05), while the concentrations of SCFA remained unchanged except an increase in n-butyric acid in colon contents (P< 0·05). The piglets fed the fenugreek diet had higher Lactobacillus and clostridium cluster I concentrations and lower Escherichia, Hafnia and Shigella concentrations in the small intestine. The addition of fenugreek increased the relative concentration of the γδ T-cell population (TCR1+CD8α-) in the blood with a simultaneous reduction of antigen-presenting cells (MHCII+CD5-) (P< 0·05). Proliferation rate and phagocytosis activity of monocytes were not affected by the additive. In conclusion, fenugreek seeds might be interesting as a feed ingredient for young piglets due to their effects on the intestinal microbiota and immunological variables. The impact on performance and animal health has to be further evaluated.

  10. Lactobacillus acidophilus NCFM affects vitamin E acetate metabolism and intestinal bile acid signature in monocolonized mice

    PubMed Central

    Roager, Henrik M; Sulek, Karolina; Skov, Kasper; Frandsen, Henrik L; Smedsgaard, Jørn; Wilcks, Andrea; Skov, Thomas H; Villas-Boas, Silas G; Licht, Tine R

    2014-01-01

    Monocolonization of germ-free (GF) mice enables the study of specific bacterial species in vivo. Lactobacillus acidophilus NCFMTM (NCFM) is a probiotic strain; however, many of the mechanisms behind its health-promoting effect remain unknown. Here, we studied the effects of NCFM on the metabolome of jejunum, cecum, and colon of NCFM monocolonized (MC) and GF mice using liquid chromatography coupled to mass-spectrometry (LC-MS). The study adds to existing evidence that NCFM in vivo affects the bile acid signature of mice, in particular by deconjugation. Furthermore, we confirmed that carbohydrate metabolism is affected by NCFM in the mouse intestine as especially the digestion of oligosaccharides (penta- and tetrasaccharides) was increased in MC mice. Additionally, levels of α-tocopherol acetate (vitamin E acetate) were higher in the intestine of GF mice than in MC mice, suggesting that NCFM affects the vitamin E acetate metabolism. NCFM did not digest vitamin E acetate in vitro, suggesting that direct bacterial metabolism was not the cause of the altered metabolome in vivo. Taken together, our results suggest that NCFM affects intestinal carbohydrate metabolism, bile acid metabolism and vitamin E metabolism, although it remains to be investigated whether this effect is unique to NCFM. PMID:24717228

  11. Fate of ingested fluids: factors affecting gastric emptying and intestinal absorption of beverages in humans.

    PubMed

    Leiper, John B

    2015-09-01

    The volume of fluid ingested for rehydration is essential in determining the restoration of euhydration because it must be in excess of the water lost since the individual was last euhydrated. The formulation of any ingested beverage is also important as this affects the rate at which the fluid is emptied from the stomach, absorbed in the small intestine, and hence assimilated into the body water pool. This review highlights the essential role of the gastrointestinal tract in the maintenance of hydration status.

  12. Cell motility and biofilm formation in Bacillus subtilis are affected by the ribosomal proteins, S11 and S21.

    PubMed

    Takada, Hiraku; Morita, Masato; Shiwa, Yuh; Sugimoto, Ryoma; Suzuki, Shota; Kawamura, Fujio; Yoshikawa, Hirofumi

    2014-01-01

    Bacillus subtilis differentiates into various cellular states in response to environmental changes. It exists in two states during the exponential growth phase: motile cells and connected chains of sessile cells. Here, we identified new regulators of cell motility and chaining, the ribosomal proteins S21 (rpsU) and S11 (rpsK). Their mutants showed impaired cell motility (observed in a laboratory strain) and robust biofilm formation (observed in an undomesticated strain). The two major operons for biofilm formation, tapA-sipW-tasA and epsA-O, were strongly expressed in the rpsU mutant, whereas the flagellin-encoding hag gene and other SigD-dependent motility regulons were not. Genetic analysis revealed that the mutation of remA, the transcriptional activator of the eps operon, is epistatic to that of rpsU, whereas the mutation of antagonistic regulators of SinR is not. Our studies demonstrate that S11 and S21 participate in the regulation of bistability via the RemA/RemB pathway.

  13. Modulation of Intracellular Calcium Levels by Calcium Lactate Affects Colon Cancer Cell Motility through Calcium-Dependent Calpain

    PubMed Central

    Sundaramoorthy, Pasupathi; Sim, Jae Jun; Jang, Yeong-Su; Mishra, Siddhartha Kumar; Jeong, Keun-Yeong; Mander, Poonam; Chul, Oh Byung; Shim, Won-Sik; Oh, Seung Hyun; Nam, Ky-Youb; Kim, Hwan Mook

    2015-01-01

    Cancer cell motility is a key phenomenon regulating invasion and metastasis. Focal adhesion kinase (FAK) plays a major role in cellular adhesion and metastasis of various cancers. The relationship between dietary supplementation of calcium and colon cancer has been extensively investigated. However, the effect of calcium (Ca2+) supplementation on calpain-FAK-motility is not clearly understood. We sought to identify the mechanism of FAK cleavage through Ca2+ bound lactate (CaLa), its downstream signaling and role in the motility of human colon cancer cells. We found that treating HCT116 and HT-29 cells with CaLa immediately increased the intracellular Ca2+ (iCa2+) levels for a prolonged period of time. Ca2+ influx induced cleavage of FAK into an N-terminal FAK (FERM domain) in a dose-dependent manner. Phosphorylated FAK (p-FAK) was also cleaved in to its p-N-terminal FAK. CaLa increased colon cancer cells motility. Calpeptin, a calpain inhibitor, reversed the effects of CaLa on FAK and pFAK cleavage in both cancer cell lines. The cleaved FAK translocates into the nucleus and modulates p53 stability through MDM2-associated ubiquitination. CaLa-induced Ca2+ influx increased the motility of colon cancer cells was mediated by calpain activity through FAK and pFAK protein destabilization. In conclusion, these results suggest that careful consideration may be given in deciding dietary Ca2+ supplementation to patient undergoing treatment for metastatic cancer. PMID:25629974

  14. Interventions That Affect Gastrointestinal Motility in Hospitalized Adult Patients: A Systematic Review and Meta-Analysis of Double-Blind Placebo-Controlled Randomized Trials.

    PubMed

    Asrani, Varsha M; Yoon, Harry D; Megill, Robin D; Windsor, John A; Petrov, Maxim S

    2016-02-01

    Gastrointestinal (GI) dysmotility is a common complication in acute, critically ill, postoperative, and chronic patients that may lead to impaired nutrient delivery, poor clinical, and patient-reported outcomes. Several pharmacological and nonpharmacological interventions to treat GI dysmotility were investigated in dozens of clinical studies. However, they often yielded conflicting results, at least in part, because various (nonstandardized) definitions of GI dysmotility were used and methodological quality of studies was poor. While a universally accepted definition of GI dysmotility is yet to be developed, a systematic analysis of data derived from double-blind placebo-controlled randomized trials may provide robust data on absolute and relative effectiveness of various interventions as the study outcome (GI motility) was assessed in the least biased manner.To systematically review data from double-blind placebo-controlled randomized trials to determine and compare the effectiveness of interventions that affect GI motility.Three electronic databases (MEDLINE, SCOPUS, and EMBASE) were searched. A random effects model was used for meta-analysis. The summary estimates were reported as mean difference (MD) with the corresponding 95% confidence interval (CI).A total of 38 double-blind placebo-controlled randomized trials involving 2371 patients were eligible for inclusion in the systematic review. These studies investigated a total of 20 different interventions, of which 6 interventions were meta-analyzed. Of them, the use of dopamine receptor antagonists (MD, -8.99; 95% CI, -17.72 to -0.27; P = 0.04) and macrolides (MD, -26.04; 95% CI, -51.25 to -0.82; P = 0.04) significantly improved GI motility compared with the placebo group. The use of botulism toxin significantly impaired GI motility compared with the placebo group (MD, 5.31; 95% CI, -0.04 to 10.67; P = 0.05). Other interventions (dietary factors, probiotics, hormones) did not affect GI motility

  15. Early-Life Environmental Variation Affects Intestinal Microbiota and Immune Development in New-Born Piglets

    PubMed Central

    Zhang, Ling-li; Vastenhouw, Stéphanie A.; Heilig, Hans G. H. J.; Smidt, Hauke; Rebel, Johanna M. J.; Smits, Mari A.

    2014-01-01

    Background Early-life environmental variation affects gut microbial colonization and immune competence development; however, the timing and additional specifics of these processes are unknown. The impact of early-life environmental variations, as experienced under real life circumstances, on gut microbial colonization and immune development has not been studied extensively so far. We designed a study to investigate environmental variation, experienced early after birth, to gut microbial colonization and intestinal immune development. Methodology/Principal Findings To investigate effects of early-life environmental changes, the piglets of 16 piglet litters were divided into 3 groups per litter and experimentally treated on day 4 after birth. During the course of the experiment, the piglets were kept with their mother sow. Group 1 was not treated, group 2 was treated with an antibiotic, and group 3 was treated with an antibiotic and simultaneously exposed to several routine, but stressful management procedures, including docking, clipping and weighing. Thereafter, treatment effects were measured at day 8 after birth in 16 piglets per treatment group by community-scale analysis of gut microbiota and genome-wide intestinal transcriptome profiling. We observed that the applied antibiotic treatment affected the composition and diversity of gut microbiota and reduced the expression of a large number of immune-related processes. The effect of management procedures on top of the use of an antibiotic was limited. Conclusions/Significance We provide direct evidence that different early-life conditions, specifically focusing on antibiotic treatment and exposure to stress, affect gut microbial colonization and intestinal immune development. This reinforces the notion that the early phase of life is critical for intestinal immune development, also under regular production circumstances. PMID:24941112

  16. Motile properties of the bi-directional kinesin-5 Cin8 are affected by phosphorylation in its motor domain

    PubMed Central

    Shapira, Ofer; Gheber, Larisa

    2016-01-01

    The Saccharomyces cerevisiae kinesin-5 Cin8 performs essential mitotic functions in spindle assembly and anaphase B spindle elongation. Recent work has shown that Cin8 is a bi-directional motor which moves towards the minus-end of microtubules (MTs) under high ionic strength (IS) conditions and changes directionality in low IS conditions and when bound between anti-parallel microtubules. Previous work from our laboratory has also indicated that Cin8 is differentially phosphorylated during late anaphase at cyclin-dependent kinase 1 (Cdk1)-specific sites located in its motor domain. In vivo, such phosphorylation causes Cin8 detachment from spindles and reduces the spindle elongation rate, while maintaining proper spindle morphology. To study the effect of phosphorylation on Cin8 motor function, we examined in vitro motile properties of wild type Cin8, as well as its phosphorylation using phospho-deficient and phospho-mimic variants, in a single molecule fluorescence motility assay. Analysis was performed on whole cell extracts and on purified Cin8 samples. We found that addition of negative charges in the phospho-mimic mutant weakened the MT-motor interaction, increased motor velocity and promoted minus-end-directed motility. These results indicate that phosphorylation in the catalytic domain of Cin8 regulates its motor function. PMID:27216310

  17. Motile properties of the bi-directional kinesin-5 Cin8 are affected by phosphorylation in its motor domain.

    PubMed

    Shapira, Ofer; Gheber, Larisa

    2016-01-01

    The Saccharomyces cerevisiae kinesin-5 Cin8 performs essential mitotic functions in spindle assembly and anaphase B spindle elongation. Recent work has shown that Cin8 is a bi-directional motor which moves towards the minus-end of microtubules (MTs) under high ionic strength (IS) conditions and changes directionality in low IS conditions and when bound between anti-parallel microtubules. Previous work from our laboratory has also indicated that Cin8 is differentially phosphorylated during late anaphase at cyclin-dependent kinase 1 (Cdk1)-specific sites located in its motor domain. In vivo, such phosphorylation causes Cin8 detachment from spindles and reduces the spindle elongation rate, while maintaining proper spindle morphology. To study the effect of phosphorylation on Cin8 motor function, we examined in vitro motile properties of wild type Cin8, as well as its phosphorylation using phospho-deficient and phospho-mimic variants, in a single molecule fluorescence motility assay. Analysis was performed on whole cell extracts and on purified Cin8 samples. We found that addition of negative charges in the phospho-mimic mutant weakened the MT-motor interaction, increased motor velocity and promoted minus-end-directed motility. These results indicate that phosphorylation in the catalytic domain of Cin8 regulates its motor function. PMID:27216310

  18. Tumor suppressor KAI1 affects integrin {alpha}v{beta}3-mediated ovarian cancer cell adhesion, motility, and proliferation

    SciTech Connect

    Ruseva, Zlatna; Geiger, Pamina Xenia Charlotte; Hutzler, Peter; Kotzsch, Matthias; Luber, Birgit; Schmitt, Manfred; Gross, Eva; Reuning, Ute

    2009-06-10

    The tetraspanin KAI1 had been described as a metastasis suppressor in many different cancer types, a function for which associations of KAI1 with adhesion and signaling receptors of the integrin superfamily likely play a role. In ovarian cancer, integrin {alpha}v{beta}3 correlates with tumor progression and its elevation in vitro provoked enhanced cell adhesion accompanied by significant increases in cell motility and proliferation in the presence of its major ligand vitronectin. In the present study, we characterized integrin {alpha}v{beta}3-mediated tumor biological effects as a function of cellular KAI1 restoration and proved for the first time that KAI1, besides its already known physical crosstalk with {beta}1-integrins, also colocalizes with integrin {alpha}v{beta}3. Functionally, elevated KAI1 levels drastically increased integrin {alpha}v{beta}3/vitronectin-dependent ovarian cancer cell adhesion. Since an intermediate level of cell adhesive strength is required for optimal cell migration, we next studied ovarian cancer cell motility as a function of KAI1 restoration. By time lapse video microscopy, we found impaired integrin {alpha}v{beta}3/vitronectin-mediated cell migration most probably due to strongly enhanced cellular immobilization onto the adhesion-supporting matrix. Moreover, KAI1 reexpression significantly diminished cell proliferation. These data strongly indicate that KAI1 may suppress ovarian cancer progression by inhibiting integrin {alpha}v{beta}3/vitronectin-provoked tumor cell motility and proliferation as important hallmarks of the oncogenic process.

  19. Gastrointestinal Motility Disorders and Acupuncture

    PubMed Central

    Yin, Jieyun; Chen, Jiande D Z

    2010-01-01

    During the last decades, numerous studies have been performed to investigate the effects and mechanisms of acupuncture or electroacupuncture (EA) on gastrointestinal motility and patients with functional gastrointestinal diseases. A PubMed search was performed on this topic and all available studies published in English have been reviewed and evaluated. This review is organized based on the gastrointestinal organ (from the esophagus to the colon), components of gastrointestinal motility and the functional diseases related to specific motility disorders. It was found that the effects of acupuncture or EA on gastrointestinal motility were fairly consistent and the major acupuncture points used in these studies were ST36 and PC6. Gastric motility has been mostly studied, whereas much less information is available on the effect of EA on small and large intestinal motility or related disorders. A number of clinical studies have been published, investigating the therapeutic effects of EA on a number of functional gastrointestinal diseases, such as gastroesophageal reflux, functional dyspepsia and irritable bowel syndrome. However, the findings of these clinical studies were inconclusive. In summary, acupuncture or EA is able to alter gastrointestinal motility functions and improve gastrointestinal motility disorders. However, more studies are needed to establish the therapeutic roles of EA in treating functional gastrointestinal diseases. PMID:20363196

  20. Food contaminant zearalenone and its metabolites affect cytokine synthesis and intestinal epithelial integrity of porcine cells.

    PubMed

    Marin, Daniela E; Motiu, Monica; Taranu, Ionelia

    2015-06-01

    The intestinal epithelium is the first barrier against food contaminants. Zearalenone (ZEN) is an estrogenic mycotoxin that was identified as a common contaminant of cereal grains and food and feedstuffs. In the present study, we have investigated the in vitro effects of ZEN and some of its metabolites (α-ZOL, β-ZOL) in concentrations of 10-100 µM on a swine epithelial cell line: Intestinal porcine epithelial cells (IPEC-1). We demonstrated that both ZEN metabolites were more toxic for IPEC cells as resulted from the XTT test, while for doses lower than 10 µM, only β-ZOL showed a more pronounced cytotoxicity versus epithelial cells as resulted from neutral red assay. ZEN has no effect on TER values, while α-ZOL significantly decreased the TER values, starting with day 4 of treatment. β-ZOL had a dual effect, firstly it induced a significant increase of TER, and then, starting on day 6, it induced a dramatic decrease of TER values as compared with on day 0. Concerning the cytokine synthesis, our results showed that ZEN has a tendency to increase the synthesis of IL-8 and IL-10. By contrast, α- and β-ZOL decreased the expression of both IL-8 and IL-10, in a dose dependent manner. In conclusion, our results showed that ZEN and its metabolites differently affected porcine intestinal cell viability, transepithelial resistance and cytokine synthesis with important implication for gut health. PMID:26035492

  1. Food Contaminant Zearalenone and Its Metabolites Affect Cytokine Synthesis and Intestinal Epithelial Integrity of Porcine Cells

    PubMed Central

    Marin, Daniela E.; Motiu, Monica; Taranu, Ionelia

    2015-01-01

    The intestinal epithelium is the first barrier against food contaminants. Zearalenone (ZEN) is an estrogenic mycotoxin that was identified as a common contaminant of cereal grains and food and feedstuffs. In the present study, we have investigated the in vitro effects of ZEN and some of its metabolites (α-ZOL, β-ZOL) in concentrations of 10–100 µM on a swine epithelial cell line: Intestinal porcine epithelial cells (IPEC-1). We demonstrated that both ZEN metabolites were more toxic for IPEC cells as resulted from the XTT test, while for doses lower than 10 µM, only β-ZOL showed a more pronounced cytotoxicity versus epithelial cells as resulted from neutral red assay. ZEN has no effect on TER values, while α-ZOL significantly decreased the TER values, starting with day 4 of treatment. β-ZOL had a dual effect, firstly it induced a significant increase of TER, and then, starting on day 6, it induced a dramatic decrease of TER values as compared with on day 0. Concerning the cytokine synthesis, our results showed that ZEN has a tendency to increase the synthesis of IL-8 and IL-10. By contrast, α- and β-ZOL decreased the expression of both IL-8 and IL-10, in a dose dependent manner. In conclusion, our results showed that ZEN and its metabolites differently affected porcine intestinal cell viability, transepithelial resistance and cytokine synthesis with important implication for gut health. PMID:26035492

  2. Food contaminant zearalenone and its metabolites affect cytokine synthesis and intestinal epithelial integrity of porcine cells.

    PubMed

    Marin, Daniela E; Motiu, Monica; Taranu, Ionelia

    2015-05-29

    The intestinal epithelium is the first barrier against food contaminants. Zearalenone (ZEN) is an estrogenic mycotoxin that was identified as a common contaminant of cereal grains and food and feedstuffs. In the present study, we have investigated the in vitro effects of ZEN and some of its metabolites (α-ZOL, β-ZOL) in concentrations of 10-100 µM on a swine epithelial cell line: Intestinal porcine epithelial cells (IPEC-1). We demonstrated that both ZEN metabolites were more toxic for IPEC cells as resulted from the XTT test, while for doses lower than 10 µM, only β-ZOL showed a more pronounced cytotoxicity versus epithelial cells as resulted from neutral red assay. ZEN has no effect on TER values, while α-ZOL significantly decreased the TER values, starting with day 4 of treatment. β-ZOL had a dual effect, firstly it induced a significant increase of TER, and then, starting on day 6, it induced a dramatic decrease of TER values as compared with on day 0. Concerning the cytokine synthesis, our results showed that ZEN has a tendency to increase the synthesis of IL-8 and IL-10. By contrast, α- and β-ZOL decreased the expression of both IL-8 and IL-10, in a dose dependent manner. In conclusion, our results showed that ZEN and its metabolites differently affected porcine intestinal cell viability, transepithelial resistance and cytokine synthesis with important implication for gut health.

  3. Targeted disruption of glycogen synthase kinase 3A (GSK3A) in mice affects sperm motility resulting in male infertility.

    PubMed

    Bhattacharjee, Rahul; Goswami, Suranjana; Dudiki, Tejasvi; Popkie, Anthony P; Phiel, Christopher J; Kline, Douglas; Vijayaraghavan, Srinivasan

    2015-03-01

    The signaling enzyme glycogen synthase kinase 3 (GSK3) exists as two isoforms-GSK3A and GSK3B. Protein phosphorylation by GSK3 has important signaling roles in several cells. In our past work, we found that both isoforms of GSK3 are present in mouse sperm and that catalytic GSK3 activity correlates with motility of sperm from several species. Here, we examined the role of Gsk3a in male fertility using a targeted gene knockout (KO) approach. The mutant mice are viable, but have a male infertility phenotype, while female fertility is unaffected. Testis weights of Gsk3a(-/-) mice are normal and sperm are produced in normal numbers. Although spermatogenesis is apparently unimpaired, sperm motility parameters in vitro are impaired. In addition, the flagellar waveform appears abnormal, characterized by low amplitude of flagellar beat. Sperm ATP levels were lower in Gsk3a(-/-) mice compared to wild-type animals. Protein phosphatase PP1 gamma2 protein levels were unaltered, but its catalytic activity was elevated in KO sperm. Remarkably, tyrosine phosphorylation of hexokinase and capacitation-associated changes in tyrosine phosphorylation of proteins are absent or significantly lower in Gsk3a(-/-) sperm. The GSK3B isoform was present and unaltered in testis and sperm of Gsk3a(-/-) mice, showing the inability of GSK3B to substitute for GSK3A in this context. Our studies show that sperm GSK3A is essential for male fertility. In addition, the GSK3A isoform, with its highly conserved glycine-rich N terminus in mammals, may have an isoform-specific role in its requirement for normal sperm motility and fertility.

  4. Down-regulation of UDP-glucose dehydrogenase affects glycosaminoglycans synthesis and motility in HCT-8 colorectal carcinoma cells

    SciTech Connect

    Wang, Tsung-Pao; Pan, Yun-Ru; Fu, Chien-Yu; Chang, Hwan-You

    2010-10-15

    UDP-glucose dehydrogenase (UGDH) catalyzes oxidation of UDP-glucose to yield UDP-glucuronic acid, a precursor of hyaluronic acid (HA) and other glycosaminoglycans (GAGs) in extracellular matrix. Although association of extracellular matrix with cell proliferation and migration has been well documented, the importance of UGDH in these behaviors is not clear. Using UGDH-specific small interference RNA to treat HCT-8 colorectal carcinoma cells, a decrease in both mRNA and protein levels of UGDH, as well as the cellular UDP-glucuronic acid and GAG production was observed. Treatment of HCT-8 cells with either UGDH-specific siRNA or HA synthesis inhibitor 4-methylumbelliferone effectively delayed cell aggregation into multicellular spheroids and impaired cell motility in both three-dimensional collagen gel and transwell migration assays. The reduction in cell aggregation and migration rates could be restored by addition of exogenous HA. These results indicate that UGDH can regulate cell motility through the production of GAG. The enzyme may be a potential target for therapeutic intervention of colorectal cancers.

  5. The group I pilin glycan affects type IVa pilus hydrophobicity and twitching motility in Pseudomonas aeruginosa 1244

    PubMed Central

    Allison, Tara M.; Conrad, Sean

    2015-01-01

    The group I pilin category is the most common type of type IVa pilus produced by Pseudomonas aeruginosa. The lateral surfaces of these pili are characterized by the presence of closely spaced, covalently attached O-antigen repeating units. The current work was conducted to investigate the pilin glycan's effect on pilus solubility and function. Culture supernatant fluids containing fully, partially and non-glycosylated P. aeruginosa group I pili were tested for solubility in the presence of ammonium sulfate. These results showed that while pili expressing three or four sugars were highly soluble under all conditions, those with fewer than three were insoluble under the lowest salt concentrations tested. A representative of the P. aeruginosa group II pili also showed low solubility when assayed under these same conditions. Reduced solubility suggested an increased pilus surface hydrophobicity, which was supported by protein modelling. While having no effect on the WT strain, an ionic strength found at many host infection sites inhibited surface and subsurface twitching motility of strain 1244G7, an isogenic mutant unable to glycosylate pilin. This effect was reversed by mutant complementation. Twitching motility of P. aeruginosa strain PA103, which produces group II pili, was also inhibited by ionic strengths which influenced the mutant 1244 strain. We suggest that the group I pilin glycan may, therefore, be beneficial to this organism specifically for optimal pilus functioning at the many host disease sites with ionic strengths comparable to those tested here. PMID:26297472

  6. Antibiotic Treatment Affects Intestinal Permeability and Gut Microbial Composition in Wistar Rats Dependent on Antibiotic Class

    PubMed Central

    Tulstrup, Monica Vera-Lise; Christensen, Ellen Gerd; Carvalho, Vera; Linninge, Caroline; Ahrné, Siv; Højberg, Ole; Licht, Tine Rask; Bahl, Martin Iain

    2015-01-01

    Antibiotics are frequently administered orally to treat bacterial infections not necessarily related to the gastrointestinal system. This has adverse effects on the commensal gut microbial community, as it disrupts the intricate balance between specific bacterial groups within this ecosystem, potentially leading to dysbiosis. We hypothesized that modulation of community composition and function induced by antibiotics affects intestinal integrity depending on the antibiotic administered. To address this a total of 60 Wistar rats (housed in pairs with 6 cages per group) were dosed by oral gavage with either amoxicillin (AMX), cefotaxime (CTX), vancomycin (VAN), metronidazole (MTZ), or water (CON) daily for 10–11 days. Bacterial composition, alpha diversity and caecum short chain fatty acid levels were significantly affected by AMX, CTX and VAN, and varied among antibiotic treatments. A general decrease in diversity and an increase in the relative abundance of Proteobacteria was observed for all three antibiotics. Additionally, the relative abundance of Bifidobacteriaceae was increased in the CTX group and both Lactobacillaceae and Verrucomicrobiaceae were increased in the VAN group compared to the CON group. No changes in microbiota composition or function were observed following MTZ treatment. Intestinal permeability to 4 kDa FITC-dextran decreased after CTX and VAN treatment and increased following MTZ treatment. Plasma haptoglobin levels were increased by both AMX and CTX but no changes in expression of host tight junction genes were found in any treatment group. A strong correlation between the level of caecal succinate, the relative abundance of Clostridiaceae 1 family in the caecum, and the level of acute phase protein haptoglobin in blood plasma was observed. In conclusion, antibiotic-induced changes in microbiota may be linked to alterations in intestinal permeability, although the specific interactions remain to be elucidated as changes in permeability did

  7. High-fibre sunflower cake affects small intestinal digestion and health in broiler chickens.

    PubMed

    Kalmendal, R; Elwinger, K; Holm, L; Tauson, R

    2011-02-01

    1. An experiment was conducted to evaluate high-fibre sunflower cake (HF-SFC); a feed ingredient distinguished by large amounts of crude fibre and insoluble non-starch polysaccharides (i-NSP). 2. Broiler chickens (n = 160) were fed on pelleted maize-based diets free from coccidiostats and antibiotic growth promoters between 15 and 31 d of age. Diets included 0, 10, 20 or 30% HF-SFC. Performance and small intestinal health were assessed. 3. In general, HF-SFC inclusion mediated significant linear increases in ileal digestibility of fat and protein and significant linear decreases in ileal digestibility of dry matter, ash and energy. 4. Weight gain increased linearly with HF-SFC inclusion. Feed conversion was negatively affected by 30% HF-SFC but not by 20% HF-SFC. 5. In the jejunal lumen, inclusion of HF-SFC was associated with significant decreases in colony counts of Clostridium spp. 6. HF-SFC inclusion resulted in significant linear reductions of villus height, thickness of muscularis mucosa, and the circular and longitudinal layers of muscularis in the jejunum. Crypt depth and submucosal thickness were not affected. 7. The data indicate that broiler chickens may thrive on feeds with insoluble fibre contents far exceeding those used in practice, and that HF-SFC exerts some positive effects on digestion and small intestinal health. PMID:21337203

  8. Inactivation of Cyclic Di-GMP Binding Protein TDE0214 Affects the Motility, Biofilm Formation, and Virulence of Treponema denticola

    PubMed Central

    Bian, Jiang; Liu, Xiangyang; Cheng, Yi-Qiang

    2013-01-01

    As a ubiquitous second messenger, cyclic dimeric GMP (c-di-GMP) has been studied in numerous bacteria. The oral spirochete Treponema denticola, a periodontal pathogen associated with human periodontitis, has a complex c-di-GMP signaling network. However, its function remains unexplored. In this report, a PilZ-like c-di-GMP binding protein (TDE0214) was studied to investigate the role of c-di-GMP in the spirochete. TDE0214 harbors a PilZ domain with two signature motifs: RXXXR and DXSXXG. Biochemical studies showed that TDE0214 binds c-di-GMP in a specific manner, with a dissociation constant (Kd) value of 1.73 μM, which is in the low range compared to those of other reported c-di-GMP binding proteins. To reveal the role of c-di-GMP in T. denticola, a TDE0214 deletion mutant (TdΔ214) was constructed and analyzed in detail. First, swim plate and single-cell tracking analyses showed that TdΔ214 had abnormal swimming behaviors: the mutant was less motile and reversed more frequently than the wild type. Second, we found that biofilm formation of TdΔ214 was substantially repressed (∼6.0-fold reduction). Finally, in vivo studies using a mouse skin abscess model revealed that the invasiveness and ability to induce skin abscesses and host humoral immune responses were significantly attenuated in TdΔ214, indicative of the impact that TDE0214 has on the virulence of T. denticola. Collectively, the results reported here indicate that TDE0214 plays important roles in motility, biofilm formation, and virulence of the spirochete. This report also paves a way to further unveil the roles of the c-di-GMP signaling network in the biology and pathogenicity of T. denticola. PMID:23794624

  9. MasABK Proteins Interact with Proteins of the Type IV Pilin System to Affect Social Motility of Myxococcus xanthus

    PubMed Central

    Fremgen, Sarah; Williams, Amanda; Furusawa, Gou; Dziewanowska, Katarzyna; Settles, Matthew; Hartzell, Patricia

    2013-01-01

    Gliding motility is critical for normal development of spore-filled fruiting bodies in the soil bacterium Myxococcus xanthus. Mutations in mgl block motility and development but one mgl allele can be suppressed by a mutation in masK, the last gene in an operon adjacent to the mgl operon. Deletion of the entire 5.5 kb masABK operon crippled gliding and fruiting body development and decreased sporulation. Expression of pilAGHI, which encodes type IV pili (TFP) components essential for social (S) gliding, several cryptic pil genes, and a LuxR family protein were reduced significantly in the Δmas mutant while expression of the myxalamide operon was increased significantly. Localization and two-hybrid analysis suggest that the three Mas proteins form a membrane complex. MasA-PhoA fusions confirmed that MasA is an integral cytoplasmic membrane protein with a ≈100 amino acid periplasmic domain. Results from yeast two-hybrid assays showed that MasA interacts with the lipoprotein MasB and MasK, a protein kinase and that MasB and MasK interact with one another. Additionally, yeast two-hybrid analysis revealed a physical interaction between two gene products of the mas operon, MasA and MasB, and PilA. Deletion of mas may be accompanied by compensatory mutations since complementation of the Δmas social gliding and developmental defects required addition of both pilA and masABK. PMID:23342171

  10. The establishment of the infant intestinal microbiome is not affected by rotavirus vaccination

    PubMed Central

    Ang, Li; Arboleya, Silvia; Lihua, Guo; Chuihui, Yuan; Nan, Qin; Suarez, Marta; Solís, Gonzalo; de los Reyes-Gavilán, Clara G.; Gueimonde, Miguel

    2014-01-01

    The microbial colonization of the intestine during the first months of life constitutes the most important process for the microbiota-induced host-homeostasis. Alterations in this process may entail a high-risk for disease in later life. However, the potential factors affecting this process in the infant are not well known. Moreover, the potential impact of orally administered vaccines upon the establishing microbiome remains unknown. Here we assessed the intestinal microbiome establishment process and evaluated the impact of rotavirus vaccination upon this process. Metagenomic, PCR-DGGE and faecal short chain fatty acids analyses were performed on faecal samples obtained from three infants before and after the administration of each dose of vaccine. We found a high inter-individual variability in the early life gut microbiota at microbial composition level, but a large similarity between the infants' microbiomes at functional level. Rotavirus vaccination did not show any major effects upon the infant gut microbiota. Thus, the individual microbiome establishment and development process seems to occur in a defined manner during the first stages of life and rotavirus vaccination appears to be inconsequential for this process. PMID:25491920

  11. Intestinal Microbiota of Broiler Chickens As Affected by Litter Management Regimens.

    PubMed

    Wang, Lingling; Lilburn, Mike; Yu, Zhongtang

    2016-01-01

    Poultry litter is a mixture of bedding materials and enteric bacteria excreted by chickens, and it is typically reused for multiple growth cycles in commercial broiler production. Thus, bacteria can be transmitted from one growth cycle to the next via litter. However, it remains poorly understood how litter reuse affects development and composition of chicken gut microbiota. In this study, the effect of litter reuse on the microbiota in litter and in chicken gut was investigated using 2 litter management regimens: fresh vs. reused litter. Samples of ileal mucosa and cecal digesta were collected from young chicks (10 days of age) and mature birds (35 days of age). Based on analysis using DGGE and pyrosequencing of bacterial 16S rRNA gene amplicons, the microbiota of both the ileal mucosa and the cecal contents was affected by both litter management regimen and age of birds. Faecalibacterium, Oscillospira, Butyricicoccus, and one unclassified candidate genus closely related to Ruminococcus were most predominant in the cecal samples, while Lactobacillus was predominant in the ileal samples at both ages and in the cecal samples collected at day 10. At days 10 and 35, 8 and 3 genera, respectively, in the cecal luminal microbiota differed significantly in relative abundance between the 2 litter management regimens. Compared to the fresh litter, reused litter increased predominance of halotolerant/alkaliphilic bacteria and Faecalibacterium prausnitzii, a butyrate-producing gut bacterium. This study suggests that litter management regimens affect the chicken GI microbiota, which may impact the host nutritional status and intestinal health.

  12. Effect of drugs affecting microtubular assembly on microtubules, phospholipid synthesis and physiological indices (signalling, growth, motility and phagocytosis) in Tetrahymena pyriformis.

    PubMed

    Kovács, P; Csaba, G

    2006-01-01

    Structural changes of microtubules, incorporation of radioactively labelled components into phospholipids, cell motility, growth and phagocytosis were studied under the effect of four drugs affecting microtubular assembly: colchicine, nocodazole, vinblastine and taxol. Although the first three agents influence microtubules in the direction of depolymerization and the fourth stabilizes them, their effects on the structure of microtubules cannot be explained by this. Using confocal microscopy after an acetylated anti-tubulin label, in nocodazole- and colchicine-treated cells, the basal body cages disappear and longitudinal microtubules (LM) became thinner without changing transversal microtubules (TM). After taxol treatment LM also became thinner, however TM disappeared. Under the effect of vinblastine TM became thinner, without influencing LM. These drugs influence the incorporation of components ([(3)H]-serine, [(3)H]-palmitic acid and (32)P) into phospholipids, however their effect is equivocal and cannot be consequently coupled with the effect on the microtubules. Nocodazole, vinblastine and taxol significantly reduced the cell's motility, however colchicine did so to a lesser degree. Vinblastine and nocodazole totally inhibited, and taxol significantly decreased cell growth, while colchicine in a lower concentration increased the multiplication of cells. Phagocytosis was not significantly influenced after 1 min, but after 5 min all the agents studied (except colchicine) significantly inhibited phagocytosis. After 15 and 30 min each molecule caused highly significant inhibition. The experiments demonstrate that drugs affecting microtubular assembly dynamics influence differently the diverse (longitudinal, transversal etc.) microtubular systems of Tetrahymena and also differently influence microtubule-dependent physiological processes. The latter are more dependent on microtubular dynamics than are changes in phospholipid signalling.

  13. Is rumen development in newborn calves affected by different liquid feeds and small intestine development?

    PubMed

    Górka, P; Kowalski, Z M; Pietrzak, P; Kotunia, A; Jagusiak, W; Zabielski, R

    2011-06-01

    fed MR. Significant positive Pearson correlations were found between small intestine and reticulorumen weights as well as between activity of brush border lactase, maltase, aminopeptidase A, and aminopeptidase N and reticulorumen weight. Different liquid feeds affect small intestine development, animal growth, solid feed intake and metabolic status of calves and this effect can indirectly influence the development of forestomachs.

  14. Cytokine-induced alterations of gastrointestinal motility in gastrointestinal disorders

    PubMed Central

    Akiho, Hirotada; Ihara, Eikichi; Motomura, Yasuaki; Nakamura, Kazuhiko

    2011-01-01

    Inflammation and immune activation in the gut are usually accompanied by alteration of gastrointestinal (GI) motility. In infection, changes in motor function have been linked to host defense by enhancing the expulsion of the infectious agents. In this review, we describe the evidence for inflammation and immune activation in GI infection, inflammatory bowel disease, ileus, achalasia, eosinophilic esophagitis, microscopic colitis, celiac disease, pseudo-obstruction and functional GI disorders. We also describe the possible mechanisms by which inflammation and immune activation in the gut affect GI motility. GI motility disorder is a broad spectrum disturbance of GI physiology. Although several systems including central nerves, enteric nerves, interstitial cells of Cajal and smooth muscles contribute to a coordinated regulation of GI motility, smooth muscle probably plays the most important role. Thus, we focus on the relationship between activation of cytokines induced by adaptive immune response and alteration of GI smooth muscle contractility. Accumulated evidence has shown that Th1 and Th2 cytokines cause hypocontractility and hypercontractility of inflamed intestinal smooth muscle. Th1 cytokines downregulate CPI-17 and L-type Ca2+ channels and upregulate regulators of G protein signaling 4, which contributes to hypocontractility of inflamed intestinal smooth muscle. Conversely, Th2 cytokines cause hypercontractilty via signal transducer and activator of transcription 6 or mitogen-activated protein kinase signaling pathways. Th1 and Th2 cytokines have opposing effects on intestinal smooth muscle contraction via 5-hydroxytryptamine signaling. Understanding the immunological basis of altered GI motor function could lead to new therapeutic strategies for GI functional and inflammatory disorders. PMID:22013552

  15. Prevalence of life-threatening complications in pediatric patients affected by intestinal failure.

    PubMed

    Diamanti, A; Basso, M S; Castro, M; Calce, A; Pietrobattista, A; Gambarara, M

    2007-06-01

    Intestinal failure (IF) is defined as the reduction of functional gut mass necessary to maintain health and growth in children. Causes of IF include short bowel syndrome (SBS), neuromuscular intestinal disorders (NID), and severe protracted diarrhea (SPD). If patients require long-term parenteral nutrition (PN); they can now be discharged on home PN (HPN), thus improving their quality of life. Children requiring long-term PN are at high risk of developing life-threatening IF complications that hinder HPN, namely, IF associated liver disease (IFALD), catheter-related infections (CRI), and thrombosis. The goal of our study was to retrospectively evaluate the prevalence of life-threatening complications among IF patients according to the HPN indication. From January 1989 to May 2006, 60 IF patients (41 boys and 19 girls) underwent prolonged HPN. Total program duration was 46,391 days (127 total years, mean 2.1 years per patient). Indications for HPN were SBS in 36 cases, SPD in 19 cases, or NID in 5 cases. In our experience patients affected by SBS displayed a significantly higher prevalence of life-threatening complications than patients with other IF causes. Sixteen (27%) among 60 patients developed IFALD. CRI and thrombosis prevalence were 1.4/1000 central venous catheter (CVC) days and 0.2/1000 CVC days respectively. SBS seemed to lead to life-threatening complications more often than other HPN indications. SBS patients on long-term PN therefore require careful management to identify complications early, and they seem to be the candidates for early referral to small bowel transplantation centers.

  16. The Stringent Response Regulator DksA Is Required for Salmonella enterica Serovar Typhimurium Growth in Minimal Medium, Motility, Biofilm Formation, and Intestinal Colonization.

    PubMed

    Azriel, Shalhevet; Goren, Alina; Rahav, Galia; Gal-Mor, Ohad

    2015-11-09

    Salmonella enterica serovar Typhimurium is a facultative intracellular human and animal bacterial pathogen posing a major threat to public health worldwide. Salmonella pathogenicity requires complex coordination of multiple physiological and virulence pathways. DksA is a conserved Gram-negative regulator that belongs to a distinct group of transcription factors that bind directly to the RNA polymerase secondary channel, potentiating the effect of the signaling molecule ppGpp during a stringent response. Here, we established that in S. Typhimurium, dksA is induced during the logarithmic phase and DksA is essential for growth in minimal defined medium and plays an important role in motility and biofilm formation. Furthermore, we determined that DksA positively regulates the Salmonella pathogenicity island 1 and motility-chemotaxis genes and is necessary for S. Typhimurium invasion of human epithelial cells and uptake by macrophages. In contrast, DksA was found to be dispensable for S. Typhimurium host cell adhesion. Finally, using the colitis mouse model, we found that dksA is spatially induced at the midcecum during the early stage of the infection and required for gastrointestinal colonization and systemic infection in vivo. Taken together, these data indicate that the ancestral stringent response regulator DksA coordinates various physiological and virulence S. Typhimurium programs and therefore is a key virulence regulator of Salmonella.

  17. The Stringent Response Regulator DksA Is Required for Salmonella enterica Serovar Typhimurium Growth in Minimal Medium, Motility, Biofilm Formation, and Intestinal Colonization

    PubMed Central

    Azriel, Shalhevet; Goren, Alina; Rahav, Galia

    2015-01-01

    Salmonella enterica serovar Typhimurium is a facultative intracellular human and animal bacterial pathogen posing a major threat to public health worldwide. Salmonella pathogenicity requires complex coordination of multiple physiological and virulence pathways. DksA is a conserved Gram-negative regulator that belongs to a distinct group of transcription factors that bind directly to the RNA polymerase secondary channel, potentiating the effect of the signaling molecule ppGpp during a stringent response. Here, we established that in S. Typhimurium, dksA is induced during the logarithmic phase and DksA is essential for growth in minimal defined medium and plays an important role in motility and biofilm formation. Furthermore, we determined that DksA positively regulates the Salmonella pathogenicity island 1 and motility-chemotaxis genes and is necessary for S. Typhimurium invasion of human epithelial cells and uptake by macrophages. In contrast, DksA was found to be dispensable for S. Typhimurium host cell adhesion. Finally, using the colitis mouse model, we found that dksA is spatially induced at the midcecum during the early stage of the infection and required for gastrointestinal colonization and systemic infection in vivo. Taken together, these data indicate that the ancestral stringent response regulator DksA coordinates various physiological and virulence S. Typhimurium programs and therefore is a key virulence regulator of Salmonella. PMID:26553464

  18. Insights into Embryo Defenses of the Invasive Apple Snail Pomacea canaliculata: Egg Mass Ingestion Affects Rat Intestine Morphology and Growth

    PubMed Central

    Gimeno, Eduardo J.; Heras, Horacio

    2014-01-01

    Background The spread of the invasive snail Pomacea canaliculata is expanding the rat lungworm disease beyond its native range. Their toxic eggs have virtually no predators and unusual defenses including a neurotoxic lectin and a proteinase inhibitor, presumably advertised by a warning coloration. We explored the effect of egg perivitellin fluid (PVF) ingestion on the rat small intestine morphology and physiology. Methodology/Principal Findings Through a combination of biochemical, histochemical, histopathological, scanning electron microscopy, cell culture and feeding experiments, we analyzed intestinal morphology, growth rate, hemaglutinating activity, cytotoxicity and cell proliferation after oral administration of PVF to rats. PVF adversely affects small intestine metabolism and morphology and consequently the standard growth rate, presumably by lectin-like proteins, as suggested by PVF hemaglutinating activity and its cytotoxic effect on Caco-2 cell culture. Short-term effects of ingested PVF were studied in growing rats. PVF-supplemented diet induced the appearance of shorter and wider villi as well as fused villi. This was associated with changes in glycoconjugate expression, increased cell proliferation at crypt base, and hypertrophic mucosal growth. This resulted in a decreased absorptive surface after 3 days of treatment and a diminished rat growth rate that reverted to normal after the fourth day of treatment. Longer exposure to PVF induced a time-dependent lengthening of the small intestine while switching to a control diet restored intestine length and morphology after 4 days. Conclusions/Significance Ingestion of PVF rapidly limits the ability of potential predators to absorb nutrients by inducing large, reversible changes in intestinal morphology and growth rate. The occurrence of toxins that affect intestinal morphology and absorption is a strategy against predation not recognized among animals before. Remarkably, this defense is rather similar to

  19. Mutations in zebrafish leucine-rich repeat-containing six-like affect cilia motility and result in pronephric cysts, but have variable effects on left-right patterning.

    PubMed

    Serluca, Fabrizio C; Xu, Bo; Okabe, Noriko; Baker, Kari; Lin, Shin-Yi; Sullivan-Brown, Jessica; Konieczkowski, David J; Jaffe, Kimberly M; Bradner, Joshua M; Fishman, Mark C; Burdine, Rebecca D

    2009-05-01

    Cilia defects have been implicated in a variety of human diseases and genetic disorders, but how cilia motility contributes to these phenotypes is still unknown. To further our understanding of how cilia function in development, we have cloned and characterized two alleles of seahorse, a zebrafish mutation that results in pronephric cysts. seahorse encodes Lrrc6l, a leucine-rich repeat-containing protein that is highly conserved in organisms that have motile cilia. seahorse is expressed in zebrafish tissues known to contain motile cilia. Although mutants do not affect cilia structure and retain the ability to interact with Disheveled, both alleles of seahorse strongly affect cilia motility in the zebrafish pronephros and neural tube. Intriguingly, although seahorse mutations variably affect fluid flow in Kupffer's vesicle, they can have very weak effects on left-right patterning. Combined with recently published results, our alleles suggest that the function of seahorse in cilia motility is separable from its function in other cilia-related phenotypes.

  20. Asian Motility Studies in Irritable Bowel Syndrome

    PubMed Central

    2010-01-01

    Altered motility remains one of the important pathophysiologic factors in patients with irritable bowel syndrome (IBS) who commonly complain of abdominal pain and stool changes such as diarrhea and constipation. The prevalence of IBS has increased among Asian populations these days. Gastrointestinal (GI) physiology may vary between Asian and Western populations because of differences in diets, socio-cultural backgrounds, and genetic factors. The characteristics and differences of GI dysmotility in Asian IBS patients were reviewed. MEDLINE search work was performed including following terms, 'IBS,' 'motility,' 'transit time,' 'esophageal motility,' 'gastric motility,' 'small intestinal motility,' 'colonic motility,' 'anorectal function,' and 'gallbladder motility' and over 100 articles were categorized under 'esophagus,' 'stomach,' 'small intestine,' 'colon,' 'anorectum,' 'gallbladder,' 'transit,' 'motor pattern,' and 'effect of stressors.' Delayed gastric emptying, slow tansit in constipation predominant IBS patients, rapid transit in diarrhea predominant IBS patients, accelerated motility responses to various stressors such as meals, mental stress, or corticotrophin releasing hormones, and altered rectal compliance and altered rectal accomodation were reported in many Asian studies regarding IBS. Many conflicting results were found among these studies and there are still controversies to conclude these as unique features of Asian IBS patients. Multinational and multicenter studies are needed to be performed vigorously in order to elaborate characteristics as well as differences of altered motililty in Asian patients with IBS. PMID:20535342

  1. Sperm Motility in Flow

    NASA Astrophysics Data System (ADS)

    Guasto, Jeffrey; Juarez, Gabriel; Stocker, Roman

    2012-11-01

    A wide variety of plants and animals reproduce sexually by releasing motile sperm that seek out a conspecific egg, for example in the reproductive tract for mammals or in the water column for externally fertilizing organisms. Sperm are aided in their quest by chemical cues, but must also contend with hydrodynamic forces, resulting from laminar flows in reproductive tracts or turbulence in aquatic habitats. To understand how velocity gradients affect motility, we subjected swimming sperm to a range of highly-controlled straining flows using a cross-flow microfluidic device. The motion of the cell body and flagellum were captured through high-speed video microscopy. The effects of flow on swimming are twofold. For moderate velocity gradients, flow simply advects and reorients cells, quenching their ability to cross streamlines. For high velocity gradients, fluid stresses hinder the internal bending of the flagellum, directly inhibiting motility. The transition between the two regimes is governed by the Sperm number, which compares the external viscous stresses with the internal elastic stresses. Ultimately, unraveling the role of flow in sperm motility will lead to a better understanding of population dynamics among aquatic organisms and infertility problems in humans.

  2. Intestinal Microbiota of Broiler Chickens As Affected by Litter Management Regimens.

    PubMed

    Wang, Lingling; Lilburn, Mike; Yu, Zhongtang

    2016-01-01

    Poultry litter is a mixture of bedding materials and enteric bacteria excreted by chickens, and it is typically reused for multiple growth cycles in commercial broiler production. Thus, bacteria can be transmitted from one growth cycle to the next via litter. However, it remains poorly understood how litter reuse affects development and composition of chicken gut microbiota. In this study, the effect of litter reuse on the microbiota in litter and in chicken gut was investigated using 2 litter management regimens: fresh vs. reused litter. Samples of ileal mucosa and cecal digesta were collected from young chicks (10 days of age) and mature birds (35 days of age). Based on analysis using DGGE and pyrosequencing of bacterial 16S rRNA gene amplicons, the microbiota of both the ileal mucosa and the cecal contents was affected by both litter management regimen and age of birds. Faecalibacterium, Oscillospira, Butyricicoccus, and one unclassified candidate genus closely related to Ruminococcus were most predominant in the cecal samples, while Lactobacillus was predominant in the ileal samples at both ages and in the cecal samples collected at day 10. At days 10 and 35, 8 and 3 genera, respectively, in the cecal luminal microbiota differed significantly in relative abundance between the 2 litter management regimens. Compared to the fresh litter, reused litter increased predominance of halotolerant/alkaliphilic bacteria and Faecalibacterium prausnitzii, a butyrate-producing gut bacterium. This study suggests that litter management regimens affect the chicken GI microbiota, which may impact the host nutritional status and intestinal health. PMID:27242676

  3. Intestinal Microbiota of Broiler Chickens As Affected by Litter Management Regimens

    PubMed Central

    Wang, Lingling; Lilburn, Mike; Yu, Zhongtang

    2016-01-01

    Poultry litter is a mixture of bedding materials and enteric bacteria excreted by chickens, and it is typically reused for multiple growth cycles in commercial broiler production. Thus, bacteria can be transmitted from one growth cycle to the next via litter. However, it remains poorly understood how litter reuse affects development and composition of chicken gut microbiota. In this study, the effect of litter reuse on the microbiota in litter and in chicken gut was investigated using 2 litter management regimens: fresh vs. reused litter. Samples of ileal mucosa and cecal digesta were collected from young chicks (10 days of age) and mature birds (35 days of age). Based on analysis using DGGE and pyrosequencing of bacterial 16S rRNA gene amplicons, the microbiota of both the ileal mucosa and the cecal contents was affected by both litter management regimen and age of birds. Faecalibacterium, Oscillospira, Butyricicoccus, and one unclassified candidate genus closely related to Ruminococcus were most predominant in the cecal samples, while Lactobacillus was predominant in the ileal samples at both ages and in the cecal samples collected at day 10. At days 10 and 35, 8 and 3 genera, respectively, in the cecal luminal microbiota differed significantly in relative abundance between the 2 litter management regimens. Compared to the fresh litter, reused litter increased predominance of halotolerant/alkaliphilic bacteria and Faecalibacterium prausnitzii, a butyrate-producing gut bacterium. This study suggests that litter management regimens affect the chicken GI microbiota, which may impact the host nutritional status and intestinal health. PMID:27242676

  4. Interferon Tau Affects Mouse Intestinal Microbiota and Expression of IL-17.

    PubMed

    Ren, Wenkai; Chen, Shuai; Zhang, Liwen; Liu, Gang; Hussain, Tarique; Hao, Xiao; Yin, Jie; Duan, Jielin; Tan, Bie; Wu, Guoyao; Bazer, Fuller W; Yin, Yulong

    2016-01-01

    This study was conducted to explore the effects of interferon tau (IFNT) on the intestinal microbiota and expression of interleukin 17 (IL-17) in the intestine of mice. IFNT supplementation increased microbial diversity in the jejunum and ileum but decreased microbial diversity in the feces. IFNT supplementation influenced the composition of the intestinal microbiota as follows: (1) decreasing the percentage of Firmicutes and increasing Bacteroidetes in the jejunum and ileum; (2) enhancing the percentage of Firmicutes but decreasing Bacteroidetes in the colon and feces; (3) decreasing Lactobacillus in the jejunum and ileum; (4) increasing the percentage of Blautia, Bacteroides, Alloprevotella, and Lactobacillus in the colon; and (5) increasing the percentage of Lactobacillus, Bacteroides, and Allobaculum, while decreasing Blautia in the feces. Also, IFNT supplementation decreased the expression of IL-17 in the intestines of normal mice and of an intestinal pathogen infected mice. In conclusion, IFNT supplementation modulates the intestinal microbiota and intestinal IL-17 expression, indicating the applicability of IFNT to treat the intestinal diseases involving IL-17 expression and microbiota. PMID:27610003

  5. Interferon Tau Affects Mouse Intestinal Microbiota and Expression of IL-17

    PubMed Central

    Ren, Wenkai; Chen, Shuai; Zhang, Liwen; Liu, Gang; Hussain, Tarique; Hao, Xiao; Yin, Jie; Duan, Jielin; Wu, Guoyao; Bazer, Fuller W.

    2016-01-01

    This study was conducted to explore the effects of interferon tau (IFNT) on the intestinal microbiota and expression of interleukin 17 (IL-17) in the intestine of mice. IFNT supplementation increased microbial diversity in the jejunum and ileum but decreased microbial diversity in the feces. IFNT supplementation influenced the composition of the intestinal microbiota as follows: (1) decreasing the percentage of Firmicutes and increasing Bacteroidetes in the jejunum and ileum; (2) enhancing the percentage of Firmicutes but decreasing Bacteroidetes in the colon and feces; (3) decreasing Lactobacillus in the jejunum and ileum; (4) increasing the percentage of Blautia, Bacteroides, Alloprevotella, and Lactobacillus in the colon; and (5) increasing the percentage of Lactobacillus, Bacteroides, and Allobaculum, while decreasing Blautia in the feces. Also, IFNT supplementation decreased the expression of IL-17 in the intestines of normal mice and of an intestinal pathogen infected mice. In conclusion, IFNT supplementation modulates the intestinal microbiota and intestinal IL-17 expression, indicating the applicability of IFNT to treat the intestinal diseases involving IL-17 expression and microbiota. PMID:27610003

  6. Interferon Tau Affects Mouse Intestinal Microbiota and Expression of IL-17

    PubMed Central

    Ren, Wenkai; Chen, Shuai; Zhang, Liwen; Liu, Gang; Hussain, Tarique; Hao, Xiao; Yin, Jie; Duan, Jielin; Wu, Guoyao; Bazer, Fuller W.

    2016-01-01

    This study was conducted to explore the effects of interferon tau (IFNT) on the intestinal microbiota and expression of interleukin 17 (IL-17) in the intestine of mice. IFNT supplementation increased microbial diversity in the jejunum and ileum but decreased microbial diversity in the feces. IFNT supplementation influenced the composition of the intestinal microbiota as follows: (1) decreasing the percentage of Firmicutes and increasing Bacteroidetes in the jejunum and ileum; (2) enhancing the percentage of Firmicutes but decreasing Bacteroidetes in the colon and feces; (3) decreasing Lactobacillus in the jejunum and ileum; (4) increasing the percentage of Blautia, Bacteroides, Alloprevotella, and Lactobacillus in the colon; and (5) increasing the percentage of Lactobacillus, Bacteroides, and Allobaculum, while decreasing Blautia in the feces. Also, IFNT supplementation decreased the expression of IL-17 in the intestines of normal mice and of an intestinal pathogen infected mice. In conclusion, IFNT supplementation modulates the intestinal microbiota and intestinal IL-17 expression, indicating the applicability of IFNT to treat the intestinal diseases involving IL-17 expression and microbiota.

  7. Commensal microbiota affects ischemic stroke outcome by regulating intestinal γδT cells

    PubMed Central

    Benakis, Corinne; Brea, David; Caballero, Silvia; Faraco, Giuseppe; Moore, Jamie; Murphy, Michelle; Sita, Giulia; Racchumi, Gianfranco; Ling, Lilan; Pamer, Eric G.; Iadecola, Costantino; Anrather, Josef

    2016-01-01

    Commensal gut bacteria impact the host immune system and can influence disease processes in several organs, including the brain. However, it remains unclear whether the microbiota has an impact on the outcome of acute brain injury. Here we show that antibiotic-induced alterations in the intestinal flora reduces ischemic brain injury in mice, an effect transmissible by fecal transplants. Intestinal dysbiosis alters immune homeostasis in the small intestine leading to an increase in regulatory T cells and a reduction in IL-17+ γδ T cells, through altered dendritic cell activity. Dysbiosis suppresses trafficking of effector T cells from the gut to the leptomeninges after stroke. Interleukin-10 (IL-10) and IL-17 are required for the neuroprotection afforded by intestinal dysbiosis. The findings reveal a previously unrecognized gut-brain axis and the impact of the intestinal flora and meningeal IL-17+ γδ T cells on ischemic injury. PMID:27019327

  8. Altered mucus glycosylation in core 1 O-glycan-deficient mice affects microbiota composition and intestinal architecture.

    PubMed

    Sommer, Felix; Adam, Nina; Johansson, Malin E V; Xia, Lijun; Hansson, Gunnar C; Bäckhed, Fredrik

    2014-01-01

    A functional mucus layer is a key requirement for gastrointestinal health as it serves as a barrier against bacterial invasion and subsequent inflammation. Recent findings suggest that mucus composition may pose an important selection pressure on the gut microbiota and that altered mucus thickness or properties such as glycosylation lead to intestinal inflammation dependent on bacteria. Here we used TM-IEC C1galt (-/-) mice, which carry an inducible deficiency of core 1-derived O-glycans in intestinal epithelial cells, to investigate the effects of mucus glycosylation on susceptibility to intestinal inflammation, gut microbial ecology and host physiology. We found that TM-IEC C1galt (-/-) mice did not develop spontaneous colitis, but they were more susceptible to dextran sodium sulphate-induced colitis. Furthermore, loss of core 1-derived O-glycans induced inverse shifts in the abundance of the phyla Bacteroidetes and Firmicutes. We also found that mucus glycosylation impacts intestinal architecture as TM-IEC C1galt(-/-) mice had an elongated gastrointestinal tract with deeper ileal crypts, a small increase in the number of proliferative epithelial cells and thicker circular muscle layers in both the ileum and colon. Alterations in the length of the gastrointestinal tract were partly dependent on the microbiota. Thus, the mucus layer plays a role in the regulation of gut microbiota composition, balancing intestinal inflammation, and affects gut architecture. PMID:24416370

  9. Altered Mucus Glycosylation in Core 1 O-Glycan-Deficient Mice Affects Microbiota Composition and Intestinal Architecture

    PubMed Central

    Sommer, Felix; Adam, Nina; Johansson, Malin E. V.; Xia, Lijun; Hansson, Gunnar C.; Bäckhed, Fredrik

    2014-01-01

    A functional mucus layer is a key requirement for gastrointestinal health as it serves as a barrier against bacterial invasion and subsequent inflammation. Recent findings suggest that mucus composition may pose an important selection pressure on the gut microbiota and that altered mucus thickness or properties such as glycosylation lead to intestinal inflammation dependent on bacteria. Here we used TM-IEC C1galt-/- mice, which carry an inducible deficiency of core 1-derived O-glycans in intestinal epithelial cells, to investigate the effects of mucus glycosylation on susceptibility to intestinal inflammation, gut microbial ecology and host physiology. We found that TM-IEC C1galt-/- mice did not develop spontaneous colitis, but they were more susceptible to dextran sodium sulphate-induced colitis. Furthermore, loss of core 1-derived O-glycans induced inverse shifts in the abundance of the phyla Bacteroidetes and Firmicutes. We also found that mucus glycosylation impacts intestinal architecture as TM-IEC C1galt-/- mice had an elongated gastrointestinal tract with deeper ileal crypts, a small increase in the number of proliferative epithelial cells and thicker circular muscle layers in both the ileum and colon. Alterations in the length of the gastrointestinal tract were partly dependent on the microbiota. Thus, the mucus layer plays a role in the regulation of gut microbiota composition, balancing intestinal inflammation, and affects gut architecture. PMID:24416370

  10. Diet Complexity and Estrogen Receptor β Status Affect the Composition of the Murine Intestinal Microbiota

    PubMed Central

    Menon, Rani; Watson, Sara E.; Thomas, Laura N.; Allred, Clinton D.; Dabney, Alan; Azcarate-Peril, M. Andrea

    2013-01-01

    Intestinal microbial dysbiosis contributes to the dysmetabolism of luminal factors, including steroid hormones (sterones) that affect the development of chronic gastrointestinal inflammation and the incidence of sterone-responsive cancers of the breast, prostate, and colon. Little is known, however, about the role of specific host sterone nucleoreceptors, including estrogen receptor β (ERβ), in microbiota maintenance. Herein, we test the hypothesis that ERβ status affects microbiota composition and determine if such compositionally distinct microbiota respond differently to changes in diet complexity that favor Proteobacteria enrichment. To this end, conventionally raised female ERβ+/+ and ERβ−/− C57BL/6J mice (mean age of 27 weeks) were initially reared on 8604, a complex diet containing estrogenic isoflavones, and then fed AIN-76, an isoflavone-free semisynthetic diet, for 2 weeks. 16S rRNA gene surveys revealed that the fecal microbiota of 8604-fed mice and AIN-76-fed mice differed, as expected. The relative diversity of Proteobacteria, especially the Alphaproteobacteria and Gammaproteobacteria, increased significantly following the transition to AIN-76. Distinct patterns for beneficial Lactobacillales were exclusive to and highly abundant among 8604-fed mice, whereas several Proteobacteria were exclusive to AIN-76-fed mice. Interestingly, representative orders of the phyla Proteobacteria, Bacteroidetes, and Firmicutes, including the Lactobacillales, also differed as a function of murine ERβ status. Overall, these interactions suggest that sterone nucleoreceptor status and diet complexity may play important roles in microbiota maintenance. Furthermore, we envision that this model for gastrointestinal dysbiosis may be used to identify novel probiotics, prebiotics, nutritional strategies, and pharmaceuticals for the prevention and resolution of Proteobacteria-rich dysbiosis. PMID:23872567

  11. Motility of Mycoplasma pneumoniae.

    PubMed Central

    Radestock, U; Bredt, W

    1977-01-01

    Cell of Mycoplasma pneumoniae FH gliding on a glass surface in liquid medium were examined by microscopic observation and quantitatively by microcinematography (30 frames per min). Comparisons were made only within the individual experiments. The cells moved in an irregular pattern with numerous narrow bends and circles. They never changed their leading end. The average speed (without pauses) was relatively constant between o.2 and 0.5 mum/s. The maximum speed was about 1.5 to 2.0 mum/s. The movements were interrupted by resting periods of different lengths and frequency. Temperature, viscosity, pH, and the presence of yeast extract in the medium influenced the motility significantly; changes in glucose, calcium ions, and serum content were less effective. The movements were affected by iodoacetate, p-mercuribenzoate, and mitomycin C at inhibitory or subinhibitory concentrations. Sodium fluoride, sodium cyanide, dinitrophenol, chloramphenicol, puromycin, cholchicin, and cytochalasin B at minimal inhibitory concentrations did not affect motility. The movements were effectively inhibited by anti-M. pneumoniae antiserum. Studies with absorbed antiserum suggested that the surface components involved in motility are heat labile. The gliding of M. pneumoniae cells required an intact energy metabolism and the proteins involved seemed to have a low turnover. Images PMID:14925

  12. Fascioliasis and Intestinal Parasitoses Affecting Schoolchildren in Atlixco, Puebla State, Mexico: Epidemiology and Treatment with Nitazoxanide

    PubMed Central

    Zumaquero-Ríos, José Lino; Sarracent-Pérez, Jorge; Rojas-García, Raúl; Rojas-Rivero, Lázara; Martínez-Tovilla, Yaneth; Valero, María Adela; Mas-Coma, Santiago

    2013-01-01

    Background The Atlixco municipality, Puebla State, at a mean altitude of 1840 m, was selected for a study of Fasciola hepatica infection in schoolchildren in Mexico. This area presents permanent water collections continuously receiving thaw water from Popocatepetl volcano (5426 m altitude) through the community supply channels, conforming an epidemiological scenario similar to those known in hyperendemic areas of Andean countries. Methodology and Findings A total of 865 6–14 year-old schoolchildren were analyzed with FasciDIG coproantigen test and Lumbreras rapid sedimentation technique, and quantitatively assessed with Kato-Katz. Fascioliasis prevalences ranged 2.94–13.33% according to localities (mean 5.78%). Intensities were however low (24–384 epg). The association between fascioliasis and the habit of eating raw vegetables was identified, including watercress and radish with pronouncedly higher relative risk than lettuce, corncob, spinach, alfalfa juice, and broccoli. Many F. hepatica-infected children were coinfected by other parasites. Entamoeba histolytica/dispar, Giardia intestinalis, Blastocystis hominis, Hymenolepis nana and Ascaris lumbricoides infection resulted in risk factors for F. hepatica infection. Nitazoxanide efficacy against fascioliasis was 94.0% and 100% after first and second treatment courses, respectively. The few children, for whom a second treatment course was needed, were concomitantly infected by moderate ascariasis burdens. Its efficacy was also very high in the treatment of E. histolytica/E. dispar, G. intestinalis, B. hominis, H. nana, A. lumbricoides, Trichuris trichiura, and Enterobius vermicularis. A second treatment course was needed for all children affected by ancylostomatids. Conclusions Fascioliasis prevalences indicate this area to be mesoendemic, with isolated hyperendemic foci. This is the first time that a human fascioliasis endemic area is described in North America. Nitazoxanide appears as an appropriate

  13. Acquired causes of intestinal malabsorption.

    PubMed

    van der Heide, F

    2016-04-01

    This review focuses on the acquired causes, diagnosis, and treatment of intestinal malabsorption. Intestinal absorption is a complex process that depends on many variables, including the digestion of nutrients within the intestinal lumen, the absorptive surface of the small intestine, the membrane transport systems, and the epithelial absorptive enzymes. Acquired causes of malabsorption are classified by focussing on the three phases of digestion and absorption: 1) luminal/digestive phase, 2) mucosal/absorptive phase, and 3) transport phase. Most acquired diseases affect the luminal/digestive phase. These include short bowel syndrome, extensive small bowel inflammation, motility disorders, and deficiencies of digestive enzymes or bile salts. Diagnosis depends on symptoms, physical examination, and blood and stool tests. There is no gold standard for the diagnosis of malabsorption. Further testing should be based on the specific clinical context and the suspected underlying disease. Therapy is directed at nutritional support by enteral or parenteral feeding and screening for and supplementation of deficiencies in vitamins and minerals. Early enteral feeding is important for intestinal adaptation in short bowel syndrome. Medicinal treatment options for diarrhoea in malabsorption include loperamide, codeine, cholestyramine, or antibiotics. PMID:27086886

  14. Yeast culture supplement during nursing and transport affects immunity and intestinal microbial ecology of weanling pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Weaning and transport stress can have a negative impact on the piglet's immune system and intestinal microbiota. The objective of this study was to determine the influence of a yeast product on innate immunity and microbial ecology of the gastrointestinal tract following stress of weaning and trans...

  15. Intestinal microbial affects of yeast products on weaned and transport stressed pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Study objectives were to determine effects of a commercially available yeast product (XPC, Diamond-V Mills) and stress of transportation on total Enterobacteriaceae, Escherichia coli, coliforms, and Lactobacilli populations in the intestine of weaning pigs. In a RCB design with a 2 x 2 factorial ar...

  16. Preterm infant gut microbiota affects intestinal epithelial development in a humanized microbiome gnotobiotic mouse model.

    PubMed

    Yu, Yueyue; Lu, Lei; Sun, Jun; Petrof, Elaine O; Claud, Erika C

    2016-09-01

    Development of the infant small intestine is influenced by bacterial colonization. To promote establishment of optimal microbial communities in preterm infants, knowledge of the beneficial functions of the early gut microbiota on intestinal development is needed. The purpose of this study was to investigate the impact of early preterm infant microbiota on host gut development using a gnotobiotic mouse model. Histological assessment of intestinal development was performed. The differentiation of four epithelial cell lineages (enterocytes, goblet cells, Paneth cells, enteroendocrine cells) and tight junction (TJ) formation was examined. Using weight gain as a surrogate marker for health, we found that early microbiota from a preterm infant with normal weight gain (MPI-H) induced increased villus height and crypt depth, increased cell proliferation, increased numbers of goblet cells and Paneth cells, and enhanced TJs compared with the changes induced by early microbiota from a poor weight gain preterm infant (MPI-L). Laser capture microdissection (LCM) plus qRT-PCR further revealed, in MPI-H mice, a higher expression of stem cell marker Lgr5 and Paneth cell markers Lyz1 and Cryptdin5 in crypt populations, along with higher expression of the goblet cell and mature enterocyte marker Muc3 in villus populations. In contrast, MPI-L microbiota failed to induce the aforementioned changes and presented intestinal characteristics comparable to a germ-free host. Our data demonstrate that microbial communities have differential effects on intestinal development. Future studies to identify pioneer settlers in neonatal microbial communities necessary to induce maturation may provide new insights for preterm infant microbial ecosystem therapeutics. PMID:27492329

  17. Rye affects bacterial translocation, intestinal viscosity, microbiota composition and bone mineralization in Turkey poults.

    PubMed

    Tellez, Guillermo; Latorre, Juan D; Kuttappan, Vivek A; Hargis, Billy M; Hernandez-Velasco, Xochitl

    2015-01-01

    Previously, we have reported that rye significantly increased both viscosity and Clostridium perfringens proliferation when compared with corn in an in vitro digestive model. Two independent trials were conducted to evaluate the effect of rye as a source of energy on bacterial translocation, intestinal viscosity, gut microbiota composition, and bone mineralization, when compared with corn in turkey poults. In each experiment, day-of-hatch, turkey poults were randomly assigned to either a corn or a rye diet (n = 0 /group). At 10 d of age, in both experiments, 12 birds/group were given an oral gavage dose of fluorescein isothiocyanate dextran (FITC-d). After 2.5 h of oral gavage, blood and liver samples were collected to evaluate the passage of FITC-d and bacterial translocation (BT) respectively. Duodenum, ileum and cecum gut sections were collected to evaluate intestinal viscosity and to enumerate gut microbiota. Tibias were collected for observation of bone parameters. Broilers fed with a rye diet showed increased (p<0.05) intestinal viscosity, BT, and serum FITC-d. Bacterial enumeration revealed that turkey poults fed with rye had increased the number of total lactic acid bacteria (LAB) in all three sections of the gastrointestinal tract evaluated when compared to turkey poults fed with corn. Turkey poults fed with rye also had significantly higher coliforms in duodenum and ileum but not in the ceca, whereas the total number of anaerobes increased only in duodenum. A significant reduction in bone strength and bone mineralization was observed in turkey poults fed with rye when compared with corn fed turkey poults. In conclusion, rye evoked mucosal damage in turkey poults that increased intestinal viscosity, increased leakage through the intestinal tract, and altered the microbiota composition and bone mineralization. Studies to evaluate dietary inclusion of selected Direct-Fed Microbial (DFM) candidates that produce exogenous enzymes in rye fed turkey poults are

  18. Antimicrobial resistances do not affect colonization parameters of intestinal E. coli in a small piglet group

    PubMed Central

    Schierack, Peter; Kadlec, Kristina; Guenther, Sebastian; Filter, Matthias; Schwarz, Stefan; Ewers, Christa; Wieler, Lothar H

    2009-01-01

    Background Although antimicrobial resistance and persistence of resistant bacteria in humans and animals are major health concerns worldwide, the impact of antimicrobial resistance on bacterial intestinal colonization in healthy domestic animals has only been rarely studied. We carried out a retrospective analysis of the antimicrobial susceptibility status and the presence of resistance genes in intestinal commensal E. coli clones from clinically healthy pigs from one production unit with particular focus on effects of pheno- and/or genotypic resistance on different nominal and numerical intestinal colonization parameters. In addition, we compared the occurrence of antimicrobial resistance phenotypes and genotypes with the occurrence of virulence associated genes typical for extraintestinal pathogenic E. coli. Results In general, up to 72.1% of all E. coli clones were resistant to ampicillin, chloramphenicol, kanamycin, streptomycin, sulfamethoxazole or tetracycline with a variety of different resistance genes involved. There was no significant correlation between one of the nominal or numerical colonization parameters and the absence or presence of antimicrobial resistance properties or resistance genes. However, there were several statistically significant associations between the occurrence of single resistance genes and single virulence associated genes. Conclusion The demonstrated resistance to the tested antibiotics might not play a dominant role for an intestinal colonization success in pigs in the absence of antimicrobial drugs, or cross-selection of other colonization factors e.g. virulence associated genes might compensate "the cost of antibiotic resistance". Nevertheless, resistant strains are not outcompeted by susceptible bacteria in the porcine intestine. Trial Registration The study was approved by the local animal welfare committee of the "Landesamt für Arbeitsschutz, Gesundheitsschutz und technische Sicherheit" Berlin, Germany (No. G0037/02). PMID

  19. Preterm infant gut microbiota affects intestinal epithelial development in a humanized microbiome gnotobiotic mouse model.

    PubMed

    Yu, Yueyue; Lu, Lei; Sun, Jun; Petrof, Elaine O; Claud, Erika C

    2016-09-01

    Development of the infant small intestine is influenced by bacterial colonization. To promote establishment of optimal microbial communities in preterm infants, knowledge of the beneficial functions of the early gut microbiota on intestinal development is needed. The purpose of this study was to investigate the impact of early preterm infant microbiota on host gut development using a gnotobiotic mouse model. Histological assessment of intestinal development was performed. The differentiation of four epithelial cell lineages (enterocytes, goblet cells, Paneth cells, enteroendocrine cells) and tight junction (TJ) formation was examined. Using weight gain as a surrogate marker for health, we found that early microbiota from a preterm infant with normal weight gain (MPI-H) induced increased villus height and crypt depth, increased cell proliferation, increased numbers of goblet cells and Paneth cells, and enhanced TJs compared with the changes induced by early microbiota from a poor weight gain preterm infant (MPI-L). Laser capture microdissection (LCM) plus qRT-PCR further revealed, in MPI-H mice, a higher expression of stem cell marker Lgr5 and Paneth cell markers Lyz1 and Cryptdin5 in crypt populations, along with higher expression of the goblet cell and mature enterocyte marker Muc3 in villus populations. In contrast, MPI-L microbiota failed to induce the aforementioned changes and presented intestinal characteristics comparable to a germ-free host. Our data demonstrate that microbial communities have differential effects on intestinal development. Future studies to identify pioneer settlers in neonatal microbial communities necessary to induce maturation may provide new insights for preterm infant microbial ecosystem therapeutics.

  20. Chemical form of selenium affects its uptake, transport, and glutathione peroxidase activity in the human intestinal Caco-2 cell model.

    PubMed

    Zeng, Huawei; Jackson, Matthew I; Cheng, Wen-Hsing; Combs, Gerald F

    2011-11-01

    Determining the effect of selenium (Se) chemical form on uptake, transport, and glutathione peroxidase activity in human intestinal cells is critical to assess Se bioavailability at nutritional doses. In this study, we found that two sources of L-selenomethionine (SeMet) and Se-enriched yeast each increased intracellular Se content more effectively than selenite or methylselenocysteine (SeMSC) in the human intestinal Caco-2 cell model. Interestingly, SeMSC, SeMet, and digested Se-enriched yeast were transported at comparable efficacy from the apical to basolateral sides, each being about 3-fold that of selenite. In addition, these forms of Se, whether before or after traversing from apical side to basolateral side, did not change the potential to support glutathione peroxidase (GPx) activity. Although selenoprotein P has been postulated to be a key Se transport protein, its intracellular expression did not differ when selenite, SeMSC, SeMet, or digested Se-enriched yeast was added to serum-contained media. Taken together, our data show, for the first time, that the chemical form of Se at nutritional doses can affect the absorptive (apical to basolateral side) efficacy and retention of Se by intestinal cells; but that, these effects are not directly correlated to the potential to support GPx activity.

  1. Influenza Virus Affects Intestinal Microbiota and Secondary Salmonella Infection in the Gut through Type I Interferons.

    PubMed

    Deriu, Elisa; Boxx, Gayle M; He, Xuesong; Pan, Calvin; Benavidez, Sammy David; Cen, Lujia; Rozengurt, Nora; Shi, Wenyuan; Cheng, Genhong

    2016-05-01

    Human influenza viruses replicate almost exclusively in the respiratory tract, yet infected individuals may also develop gastrointestinal symptoms, such as vomiting and diarrhea. However, the molecular mechanisms remain incompletely defined. Using an influenza mouse model, we found that influenza pulmonary infection can significantly alter the intestinal microbiota profile through a mechanism dependent on type I interferons (IFN-Is). Notably, influenza-induced IFN-Is produced in the lungs promote the depletion of obligate anaerobic bacteria and the enrichment of Proteobacteria in the gut, leading to a "dysbiotic" microenvironment. Additionally, we provide evidence that IFN-Is induced in the lungs during influenza pulmonary infection inhibit the antimicrobial and inflammatory responses in the gut during Salmonella-induced colitis, further enhancing Salmonella intestinal colonization and systemic dissemination. Thus, our studies demonstrate a systemic role for IFN-Is in regulating the host immune response in the gut during Salmonella-induced colitis and in altering the intestinal microbial balance after influenza infection. PMID:27149619

  2. Influenza Virus Affects Intestinal Microbiota and Secondary Salmonella Infection in the Gut through Type I Interferons

    PubMed Central

    Deriu, Elisa; Boxx, Gayle M.; He, Xuesong; Pan, Calvin; Benavidez, Sammy David; Cen, Lujia; Rozengurt, Nora; Shi, Wenyuan; Cheng, Genhong

    2016-01-01

    Human influenza viruses replicate almost exclusively in the respiratory tract, yet infected individuals may also develop gastrointestinal symptoms, such as vomiting and diarrhea. However, the molecular mechanisms remain incompletely defined. Using an influenza mouse model, we found that influenza pulmonary infection can significantly alter the intestinal microbiota profile through a mechanism dependent on type I interferons (IFN-Is). Notably, influenza-induced IFN-Is produced in the lungs promote the depletion of obligate anaerobic bacteria and the enrichment of Proteobacteria in the gut, leading to a “dysbiotic” microenvironment. Additionally, we provide evidence that IFN-Is induced in the lungs during influenza pulmonary infection inhibit the antimicrobial and inflammatory responses in the gut during Salmonella-induced colitis, further enhancing Salmonella intestinal colonization and systemic dissemination. Thus, our studies demonstrate a systemic role for IFN-Is in regulating the host immune response in the gut during Salmonella-induced colitis and in altering the intestinal microbial balance after influenza infection. PMID:27149619

  3. An erythromycin derivative, EM-523, induces motilin-like gastrointestinal motility in dogs.

    PubMed

    Inatomi, N; Satoh, H; Maki, Y; Hashimoto, N; Itoh, Z; Omura, S

    1989-11-01

    The effect of an erythromycin derivative, EM-523, on gastrointestinal motility was investigated in conscious dogs and compared with that of motilin cisapride, trimebutine and metoclopramide. In the fasting state, EM-523 given i.v. or i.d. at 3 micrograms/kg or more induced contractions in the stomach that migrated along the small intestine. The pattern of the contractions was very similar to that induced by motilin. In the digestive state, EM-523 increased the amplitude of gastric contractions. Cisapride and metoclopramide increased gastrointestinal motility both in the fasting and digestive states; however, their contractile pattern was different from that of EM-523. Trimebutine did not induce gastric motility in the fasting state but rather decreased gastric motility in the digestive state. The contractions induced by EM-523 and motilin were inhibited by atropine but were not affected by naloxone, suggesting that the cholinergic pathway is important in the exertion of their action. These results indicate that EM-523 mimics motilin in stimulating gastrointestinal motility and that this agent may be useful treat gastrointestinal disorders such as gastric stasis, gastroesophageal reflux, and postoperative ileus, and so forth. PMID:2810120

  4. The feed contaminant deoxynivalenol affects the intestinal barrier permeability through inhibition of protein synthesis.

    PubMed

    Awad, Wageha A; Zentek, Jürgen

    2015-06-01

    Deoxynivalenol (DON) has critical health effects if the contaminated grains consumed by humans or animals. DON can have negative effects on the active transport of glucose and amino acids in the small intestine of chickens. As the underlying mechanisms are not fully elucidated, the present study was performed to delineate more precisely the effects of cycloheximide (protein synthesis inhibitor, CHX) and DON on the intestinal absorption of nutrients. This was to confirm whether DON effects on nutrient absorption are due to an inhibition of protein synthesis. Changes in ion transport and barrier function were assessed by short-circuit current (Isc) and transepithelial ion conductance (Gt) in Ussing chambers. Addition of D-glucose or L-glutamine to the luminal side of the isolated mucosa of the jejunum increased (P < 0.001) the Isc compared with basal conditions in the control tissues. However, the Isc was not increased by the glucose or glutamine addition after pre-incubation of tissues with DON or CHX. Furthermore, both DON and CHX reduced Gt, indicating that the intestinal barrier is compromised and consequently induced a greater impairment of the barrier function. The remarkable similarity between the activity of CHX and DON on nutrient uptake is consistent with their common ability to inhibit protein synthesis. It can be concluded that the decreases in transport activity by CHX was evident in this study using the chicken as experimental model. Similarly, DON has negative effects on the active transport of some nutrients, and these can be explained by its influence on protein synthesis. PMID:24888376

  5. The feed contaminant deoxynivalenol affects the intestinal barrier permeability through inhibition of protein synthesis.

    PubMed

    Awad, Wageha A; Zentek, Jürgen

    2015-06-01

    Deoxynivalenol (DON) has critical health effects if the contaminated grains consumed by humans or animals. DON can have negative effects on the active transport of glucose and amino acids in the small intestine of chickens. As the underlying mechanisms are not fully elucidated, the present study was performed to delineate more precisely the effects of cycloheximide (protein synthesis inhibitor, CHX) and DON on the intestinal absorption of nutrients. This was to confirm whether DON effects on nutrient absorption are due to an inhibition of protein synthesis. Changes in ion transport and barrier function were assessed by short-circuit current (Isc) and transepithelial ion conductance (Gt) in Ussing chambers. Addition of D-glucose or L-glutamine to the luminal side of the isolated mucosa of the jejunum increased (P < 0.001) the Isc compared with basal conditions in the control tissues. However, the Isc was not increased by the glucose or glutamine addition after pre-incubation of tissues with DON or CHX. Furthermore, both DON and CHX reduced Gt, indicating that the intestinal barrier is compromised and consequently induced a greater impairment of the barrier function. The remarkable similarity between the activity of CHX and DON on nutrient uptake is consistent with their common ability to inhibit protein synthesis. It can be concluded that the decreases in transport activity by CHX was evident in this study using the chicken as experimental model. Similarly, DON has negative effects on the active transport of some nutrients, and these can be explained by its influence on protein synthesis.

  6. Bifidobacteria isolated from infants and cultured on human milk oligosaccharides affect intestinal epithelial function

    PubMed Central

    Chichlowski, Maciej; De Lartigue, Guillaume; German, J. Bruce; Raybould, Helen E.; Mills, David A.

    2012-01-01

    Objectives Human milk oligosaccharides (HMO) are the third most abundant component of breast milk. Our laboratory has previously revealed gene clusters specifically linked to HMO metabolism in select bifidobacteria isolated from fecal samples of infants. Our objective was to test the hypothesis that growth of select bifidobacteria on HMO stimulates the intestinal epithelium. Methods Caco-2 and HT-29 cells were incubated with lactose (LAC) or HMO-grown Bifidobacterium longum subsp. infantis (B. infantis) or B. bifidum. Bacterial adhesion and translocation was measured by real-time quantitative PCR. Expression of pro- and anti-inflammatory cytokines and tight junction proteins was analyzed by real time reverse transcriptase. Distribution of tight junction proteins was measured using immunofluorescent microscopy. Results We showed that HMO-grown B. infantis had significantly higher rate of adhesion to HT-29 cells compared to B. bifidum. B. infantis also induced expression of a cell membrane glycoprotein, P-selectin glycoprotein ligand -1. Both B. infantis and B. bifidum grown on HMO caused less occludin relocalization and higher expression of anti-inflammatory cytokine, interleukin (IL)-10 compared to LAC-grown bacteria in Caco-2 cells. B. bifidum grown on HMO showed higher expression of junctional adhesion molecule and occludin in Caco-2 cell and HT-29 cells. There were no significant differences between LAC or HMO treatments in bacterial translocation. Conclusions This study provides evidence for the specific relationship between HMO-grown bifidobacteria and intestinal epithelial cells. To our knowledge, this is the first study describing HMO-induced changes in the bifidobacteria-intestinal cells interaction. PMID:22383026

  7. Colostrum quality affects immune system establishment and intestinal development of neonatal calves.

    PubMed

    Yang, M; Zou, Y; Wu, Z H; Li, S L; Cao, Z J

    2015-10-01

    The first meal of a neonatal calf after birth is crucial for survival and health. The present experiment was performed to assess the effects of colostrum quality on IgG passive transfer, immune and antioxidant status, and intestinal morphology and histology in neonatal calves. Twenty-eight Holstein neonatal male calves were used in the current study, 24 of which were assigned to 1 of 3 treatment groups: those that received colostrum (GrC), transitional milk (GrT, which was obtained after the first milking on 2-3 d after calving), and bulk tank milk (GrB) only at birth. The 4 extra neonatal calves who were not fed any milk were assigned to the control group and were killed immediately after birth to be a negative control to small intestinal morphology and histology detection. Calves in GrC gained more body weight than in GrT, whereas GrB calves lost 0.4 kg compared with the birth weight. Serum total protein, IgG, and superoxide dismutase concentrations were highest in GrC, GrT was intermediate, whereas GrB was the lowest on d 2, 3, and 7. Apparent efficiency of absorption at 48 h, serum complement 3 (C3), and complement 4 (C4) on d 2, 3, and 7 in GrB was low compared with GrC and GrT. On the contrary, malondialdehyde on d 7 increased in GrB. Calves in GrC had better villus length and width, crypt depth, villus height/crypt depth (V/C) value, and mucosal thickness in the duodenum, jejunum, and ileum, whereas GrT calves had lower villus length and width, crypt depth, and mucosal thickness than those fed colostrum. Villi of calves in GrB were nonuniform, sparse, severely atrophied, and apically abscised, and Peyer's patches and hydroncus were detected. Overall, colostrum is the best source for calves in IgG absorption, antioxidant activities, and serum growth metabolites, and promoting intestinal development. The higher quality of colostrum calves ingested, the faster immune defense mechanism and the more healthy intestinal circumstances they established. PMID:26233454

  8. Colostrum quality affects immune system establishment and intestinal development of neonatal calves.

    PubMed

    Yang, M; Zou, Y; Wu, Z H; Li, S L; Cao, Z J

    2015-10-01

    The first meal of a neonatal calf after birth is crucial for survival and health. The present experiment was performed to assess the effects of colostrum quality on IgG passive transfer, immune and antioxidant status, and intestinal morphology and histology in neonatal calves. Twenty-eight Holstein neonatal male calves were used in the current study, 24 of which were assigned to 1 of 3 treatment groups: those that received colostrum (GrC), transitional milk (GrT, which was obtained after the first milking on 2-3 d after calving), and bulk tank milk (GrB) only at birth. The 4 extra neonatal calves who were not fed any milk were assigned to the control group and were killed immediately after birth to be a negative control to small intestinal morphology and histology detection. Calves in GrC gained more body weight than in GrT, whereas GrB calves lost 0.4 kg compared with the birth weight. Serum total protein, IgG, and superoxide dismutase concentrations were highest in GrC, GrT was intermediate, whereas GrB was the lowest on d 2, 3, and 7. Apparent efficiency of absorption at 48 h, serum complement 3 (C3), and complement 4 (C4) on d 2, 3, and 7 in GrB was low compared with GrC and GrT. On the contrary, malondialdehyde on d 7 increased in GrB. Calves in GrC had better villus length and width, crypt depth, villus height/crypt depth (V/C) value, and mucosal thickness in the duodenum, jejunum, and ileum, whereas GrT calves had lower villus length and width, crypt depth, and mucosal thickness than those fed colostrum. Villi of calves in GrB were nonuniform, sparse, severely atrophied, and apically abscised, and Peyer's patches and hydroncus were detected. Overall, colostrum is the best source for calves in IgG absorption, antioxidant activities, and serum growth metabolites, and promoting intestinal development. The higher quality of colostrum calves ingested, the faster immune defense mechanism and the more healthy intestinal circumstances they established.

  9. Retention of iron by rat intestine in vivo as affected by dietary fiber, ascorbate and citrate.

    PubMed

    Reinhold, J G; Garcia Estrada, J; Garcia, P M; Garzon, P

    1986-06-01

    The effects of pH, ascorbate, citrate and dietary fiber on retention of ferrous and ferric iron by jejuno-ileal segments of rat intestine were examined in vivo. Iron was introduced in an isosmotic solution of sodium chloride and dextrose buffered by 2-[bis(2-hydroxyethyl)amino]ethanesulfonic acid (BES) and acetate. Stabilization of the iron solutions was aided by use of iron concentrations less than or equal to 1 microgram/ml injected into the intestine for 10-min periods. Iron retention was optimal over a broad pH range from 5 to 7.8. Inclusion of ascorbic acid in the solution injected (5, 25 or 75 micrograms/ml) did not increase retention of iron in either valence state. A low concentration of sodium citrate (2 mM) had no effect on iron retention, but increasing the concentration to 5 mM released iron from the mucosa. Maize and wheat fibers decreased the retention of ferrous iron by binding and by promoting autoxidation and formation of poorly soluble iron polymers. Bound ferrous iron was released completely at pH below 5. Retention of ferric iron was also lowered in the presence of fiber, presumably as a result of polymerization. Retention of iron by the rat in the absence of ligands was independent of valence state.

  10. Fumonisins affect the intestinal microbial homeostasis in broiler chickens, predisposing to necrotic enteritis.

    PubMed

    Antonissen, Gunther; Croubels, Siska; Pasmans, Frank; Ducatelle, Richard; Eeckhaut, Venessa; Devreese, Mathias; Verlinden, Marc; Haesebrouck, Freddy; Eeckhout, Mia; De Saeger, Sarah; Antlinger, Birgit; Novak, Barbara; Martel, An; Van Immerseel, Filip

    2015-09-23

    Fumonisins (FBs) are mycotoxins produced by Fusarium fungi. This study aimed to investigate the effect of these feed contaminants on the intestinal morphology and microbiota composition, and to evaluate whether FBs predispose broilers to necrotic enteritis. One-day-old broiler chicks were divided into a group fed a control diet, and a group fed a FBs contaminated diet (18.6 mg FB1+FB2/kg feed). A significant increase in the plasma sphinganine/sphingosine ratio in the FBs-treated group (0.21 ± 0.016) compared to the control (0.14 ± 0.014) indicated disturbance of the sphingolipid biosynthesis. Furthermore, villus height and crypt depth of the ileum was significantly reduced by FBs. Denaturing gradient gel electrophoresis showed a shift in the microbiota composition in the ileum in the FBs group compared to the control. A reduced presence of low-GC containing operational taxonomic units in ileal digesta of birds exposed to FBs was demonstrated, and identified as a reduced abundance of Candidatus Savagella and Lactobaccilus spp. Quantification of total Clostridium perfringens in these ileal samples, previous to experimental infection, using cpa gene (alpha toxin) quantification by qPCR showed an increase in C. perfringens in chickens fed a FBs contaminated diet compared to control (7.5 ± 0.30 versus 6.3 ± 0.24 log10 copies/g intestinal content). After C. perfringens challenge, a higher percentage of birds developed subclinical necrotic enteritis in the group fed a FBs contaminated diet as compared to the control (44.9 ± 2.22% versus 29.8 ± 5.46%).

  11. Selective mass treatment with ivermectin to control intestinal helminthiases and parasitic skin diseases in a severely affected population.

    PubMed Central

    Heukelbach, Jörg; Winter, Benedikt; Wilcke, Thomas; Muehlen, Marion; Albrecht, Stephan; de Oliveira, Fabíola Araújo Sales; Kerr-Pontes, Lígia Regina Sansigolo; Liesenfeld, Oliver; Feldmeier, Hermann

    2004-01-01

    OBJECTIVE: To assess the short-term and long-term impact of selective mass treatment with ivermectin on the prevalence of intestinal helminthiases and parasitic skin diseases in an economically depressed community in north-east Brazil. METHODS: An intervention was carried out in a traditional fishing village in north-east Brazil where the population of 605 is heavily affected by ectoparasites and enteroparasites. The prevalence of intestinal helminths was determined by serial stool examination and the prevalence of parasitic skin diseases by clinical inspection. A total of 525 people out of a target population of 576 were treated at baseline. The majority of these were treated with ivermectin (200 microg/kg with a second dose given after 10 days). If ivermectin was contraindicated, participants were treated with albendazole or mebendazole for intestinal helminths or with topical deltamethrin for ectoparasites. Follow-up examinations were performed at 1 month and 9 months after treatment. FINDINGS: Prevalence rates of intestinal helminthiases before treatment and at 1 month and 9 months after mass treatment were: hookworm disease 28.5%, 16.4% and 7.7%; ascariasis 17.1%, 0.4% and 7.2%; trichuriasis 16.5%, 3.4% and 9.4%; strongyloidiasis 11.0%, 0.6% and 0.7%; and hymenolepiasis 0.6%; 0.4% and 0.5%, respectively. Prevalence rates of parasitic skin diseases before treatment and 1 month and 9 months after mass treatment were: active pediculosis 16.1%, 1.0% and 10.3%; scabies 3.8%, 1.0% and 1.5%; cutaneous larva migrans 0.7%, 0% and 0%; tungiasis 51.3%, 52.1% and 31.2%, respectively. Adverse events occurred in 9.4% of treatments. They were all of mild to moderate severity and were transient. CONCLUSION: Mass treatment with ivermectin was an effective and safe means of reducing the prevalence of most of the parasitic diseases prevalent in a poor community in north-east Brazil. The effects of treatment lasted for a prolonged period of time. PMID:15375445

  12. Proteome analysis of the macroscopically affected colonic mucosa of Crohn’s disease and intestinal tuberculosis

    PubMed Central

    Rukmangadachar, Lokesh A.; Makharia, Govind K.; Mishra, Asha; Das, Prasenjit; Hariprasad, Gururao; Srinivasan, Alagiri; Gupta, Siddhartha Datta; Ahuja, Vineet; Acharya, Subrat K.

    2016-01-01

    Differentiation between intestinal tuberculosis (ITB) and Crohn’s disease (CD) is challenging in geographical regions where both these diseases are prevalent. There is a need of biomarkers for differentiation between these two disorders. Colonic biopsies from inflamed mucosa of treatment-naive patients with ITB, CD and controls were used for analysis. Protein extracted from biopsies was digested with trypsin and resulting peptides were labeled with iTRAQ reagents. The peptides were subsequently analyzed using LC-MS/MS for identification and quantification. Gene ontology annotation for proteins was analyzed in PANTHER. Validation experiments were done for six differentially expressed proteins using immunohistochemistry. 533 proteins were identified and 241 proteins were quantified from 5 sets of iTRAQ experiments. While 63 were differentially expressed in colonic mucosa of patients with CD and ITB in at least one set of iTRAQ experiment, 11 proteins were differentially expressed in more than one set of experiments. Six proteins used for validation using immunohistochemistry in a larger cohort of patients; none of them however was differentially expressed in patients with ITB and CD. There are differentially expressed proteins in tissue proteome of CD and ITB. Further experiments are required using a larger cohort of homogeneous tissue samples. PMID:26988818

  13. Inhibition of β-N-acetylglucosaminidase by acetamide affects sperm motility and fertilization success of rainbow trout (Oncorhynchus mykiss) and Siberian sturgeon (Acipenser baerii).

    PubMed

    Sarosiek, B; Glogowski, J; Cejko, B I; Kujawa, R; Szczepkowski, M; Kuźmiński, H; Dobosz, S; Kowalski, R K

    2014-03-15

    β-N-Acetylglucosaminidase (β-NAGase) is an enzyme found in the sperm acrosome of numerous animal species including fish. Fish spermatozoa differ in their morphology including acrosome or acrosomeless aquasperm in chondrostean (e.g., sturgeon) and teleostean (e.g., rainbow trout). It has been shown that β-NAGase exists with high activity in both eggs and sperm of these species. The present study shows the potency of β-NAGase in fertilization. In rainbow trout, increase in sperm motility parameters (VAP and MOT) were observed in the presence of acetamide, an inhibitor for β-NAGase. In contrast, sperm motility parameters (VCL, VSL, VAP, MOT, and PRG) were reduced on the Siberian sturgeon in the presence of acetamide. The inhibition of the activity of β-NAGase in rainbow trout spermatozoa was led to a reduction in the number of fertilized eggs from 79% to 40%, whereas in sturgeon no change was observed in fertilization. Moreover, inhibition of β-NAGase in both spermatozoa and eggs of trout and sturgeon resulted in significant decrease in fertilization rate from 79% to 1% in rainbow trout and from 84% to 12% in Siberian sturgeon. Our research proves that β-NAGase can play a significant role in the fertilization process in teleosteans.

  14. Effect of compounds affecting ABCA1 expression and CETP activity on the HDL pathway involved in intestinal absorption of lutein and zeaxanthin.

    PubMed

    Niesor, Eric J; Chaput, Evelyne; Mary, Jean-Luc; Staempfli, Andreas; Topp, Andreas; Stauffer, Andrea; Wang, Haiyan; Durrwell, Alexandre

    2014-12-01

    The antioxidant xanthophylls lutein and zeaxanthin are absorbed from the diet in a process involving lipoprotein formation. Selective mechanisms exist for their intestinal uptake and tissue-selective distribution, but these are poorly understood. We investigated the role of high-density lipoprotein (HDL), apolipoprotein (apo) A1 and ATP-binding cassette transporter (ABC) A1 in intestinal uptake of lutein in a human polarized intestinal cell culture and a hamster model. Animals received dietary lutein and zeaxanthin and either a liver X receptor (LXR) agonist or statin, which up- or down-regulate intestinal ABCA1 expression, respectively. The role of HDL was studied following treatment with the cholesteryl ester transfer protein (CETP) modulator dalcetrapib or the CETP inhibitor anacetrapib. In vitro, intestinal ABCA1 at the basolateral surface of enterocytes transferred lutein and zeaxanthin to apoA1, not to mature HDL. In hamsters, plasma lutein and zeaxanthin levels were markedly increased with the LXR agonist and decreased with simvastatin. Dalcetrapib, but not anacetrapib, increased plasma and liver lutein and zeaxanthin levels. ABCA1 expression and apoA1 acceptor activity are important initial steps in intestinal uptake and maintenance of lutein and zeaxanthin levels by an HDL-dependent pathway. Their absorption may be improved by physiological and pharmacological interventions affecting HDL metabolism.

  15. Enterococcus faecium NCIMB 10415 supplementation affects intestinal immune-associated gene expression in post-weaning piglets.

    PubMed

    Siepert, Bianca; Reinhardt, Nicole; Kreuzer, Susanne; Bondzio, Angelika; Twardziok, Sven; Brockmann, Gudrun; Nöckler, Karsten; Szabó, Istvan; Janczyk, Pawel; Pieper, Robert; Tedin, Karsten

    2014-01-15

    In a Salmonella challenge study of weaned piglets supplemented with the probiotic Enterococcus faecium NCIMB 10415 (SF68), we observed a delayed, post-infection proliferative response of purified blood mononuclear cell fractions towards Salmonella antigens. In order to clarify this observation, we examined the patterns of immune-associated gene expression in long-term feeding trials of both pre- and post-weaning piglets. Piglets supplemented with E. faecium NCIMB 10415 showed a post-weaning dysregulation in the expression patterns of both pro- and anti-inflammatory cytokine expression in intestinal tissues and spleen. Piglets of the supplemented group showed significantly reduced levels of IL-8, IL-10 and the co-stimulatory molecule CD86 mRNA expression in ileal Peyer's patches. The expression of CTLA4, an inhibitor of T-cell activation/proliferation, showed similar levels of expression in all tissues examined, particularly in ileal Peyer's patches post-weaning where IL-8, IL-10 and CD86 transcript levels were significantly reduced relative to control animals. Blood serum cytokine protein levels showed elevated TGFβ in pre-weaning piglets which, together with IL-6, may have suppressed IFNγ production in the probiotic-fed animals. In a second Salmonella challenge study, post-weaning, E. faecium-fed animals showed significantly elevated levels of IL-8 gene expression in mesenteric lymph nodes, but reduced levels in the spleen. At early times post-infection, the probiotic-fed group showed similar levels of IL-10, CD86 and CTLA4 mRNA expression as the control animals in intestinal Peyer's Patches, despite high relative levels of IL-8 expression in mesenteric lymph nodes. The sum of the observations suggests that supplementation of pre-weaning piglets with E. faecium affects intestinal immune-associated gene expression, which is aggravated post-weaning when the animals receive increased levels of the probiotic in feed. We suggest the post-weaning reductions in gene

  16. Giardia Flagellar Motility Is Not Directly Required to Maintain Attachment to Surfaces

    PubMed Central

    House, Susan A.; Richter, David J.; Pham, Jonathan K.; Dawson, Scott C.

    2011-01-01

    Giardia trophozoites attach to the intestinal microvilli (or inert surfaces) using an undefined “suction-based” mechanism, and remain attached during cell division to avoid peristalsis. Flagellar motility is a key factor in Giardia's pathogenesis and colonization of the host small intestine. Specifically, the beating of the ventral flagella, one of four pairs of motile flagella, has been proposed to generate a hydrodynamic force that results in suction-based attachment via the adjacent ventral disc. We aimed to test this prevailing “hydrodynamic model” of attachment mediated by flagellar motility. We defined four distinct stages of attachment by assessing surface contacts of the trophozoite with the substrate during attachment using TIRF microscopy (TIRFM). The lateral crest of the ventral disc forms a continuous perimeter seal with the substrate, a cytological indication that trophozoites are fully attached. Using trophozoites with two types of molecularly engineered defects in flagellar beating, we determined that neither ventral flagellar beating, nor any flagellar beating, is necessary for the maintenance of attachment. Following a morpholino-based knockdown of PF16, a central pair protein, both the beating and morphology of flagella were defective, but trophozoites could still initiate proper surface contacts as seen using TIRFM and could maintain attachment in several biophysical assays. Trophozoites with impaired motility were able to attach as well as motile cells. We also generated a strain with defects in the ventral flagellar waveform by overexpressing a dominant negative form of alpha2-annexin::GFP (D122A, D275A). This dominant negative alpha2-annexin strain could initiate attachment and had only a slight decrease in the ability to withstand normal and shear forces. The time needed for attachment did increase in trophozoites with overall defective flagellar beating, however. Thus while not directly required for attachment, flagellar motility is

  17. DNA Supercoiling Regulates the Motility of Campylobacter jejuni and Is Altered by Growth in the Presence of Chicken Mucus

    PubMed Central

    Shortt, Claire; Scanlan, Eoin; Hilliard, Amber; Cotroneo, Chiara E.; Bourke, Billy

    2016-01-01

    ABSTRACT Campylobacter jejuni is the leading cause of bacterial gastroenteritis in humans, but relatively little is known about the global regulation of virulence factors during infection of chickens or humans. This study identified DNA supercoiling as playing a key role in regulating motility and flagellar protein production and found that this supercoiling-controlled regulon is induced by growth in chicken mucus. A direct correlation was observed between motility and resting DNA supercoiling levels in different strains of C. jejuni, and relaxation of DNA supercoiling resulted in decreased motility. Transcriptional analysis and Western immunoblotting revealed that a reduction in motility and DNA supercoiling affected the two-component regulatory system FlgRS and was associated with reduced FlgR expression, increased FlgS expression, and aberrant expression of flagellin subunits. Electron microscopy revealed that the flagellar structure remained intact. Growth in the presence of porcine mucin resulted in increased negative supercoiling, increased motility, increased FlgR expression, and reduced FlgS expression. Finally, this supercoiling-dependent regulon was shown to be induced by growth in chicken mucus, and the level of activation was dependent on the source of the mucus from within the chicken intestinal tract. In conclusion, this study reports for the first time the key role played by DNA supercoiling in regulating motility in C. jejuni and indicates that the induction of this supercoiling-induced regulon in response to mucus from different sources could play a critical role in regulating motility in vivo. PMID:27624126

  18. The Effect of Alcohol on Gastrointestinal Motility.

    PubMed

    Grad, Simona; Abenavoli, Ludovico; Dumitrascu, Dan L

    2016-01-01

    The Gastrointestinal (GI) tract is one of the most affected systems by alcohol consumption. Alcohol can affect the esophagus in several ways: induces mucosal inflammation, increases the risk for Barrett esophagus and esophageal cancer, and also impairs the esophageal motility. Numerous studies have reported an increased prevalence of Gastroesophageal Reflux Disease (GERD) or erosive esophagitis in alcoholics. Some alcoholics exhibit an abnormality of esophageal motility known as a "nutcracker esophagus". Alcohol effect on gastric motility depends on the alcohol concentration. In general, beverages with high alcohol concentrations (i.e., above 15 percent) appear to inhibit gastric motility and low alcohol doses (wine and beer) accelerate gastric emptying. Also, acute administration of ethanol inhibits the gastric emptying, while chronic administration of a large dose of alcohol accelerates gastric motility. The effect of alcohol on small bowel motility differs according to the type of consumption (acute or chronic). Acute administration of alcohol has been found to inhibit small bowel transit and chronic administration of a large dose of alcohol accelerates small bowel transit. This article reviews some of the below findings. PMID:27527893

  19. The CsgA and Lpp Proteins of an Escherichia coli O157:H7 Strain Affect HEp-2 Cell Invasion, Motility, and Biofilm Formation ▿

    PubMed Central

    Uhlich, Gaylen A.; Gunther, Nereus W.; Bayles, Darrell O.; Mosier, Derek A.

    2009-01-01

    In Escherichia coli O157:H7 strain ATCC 43895, a guanine-to-thymine transversion in the csgD promoter created strain 43895OR. Strain 43895OR produces an abundant extracellular matrix rich in curli fibers, forms biofilms on solid surfaces, invades cultured epithelial cells, and is more virulent in mice than strain 43895. In this study we compared the formic acid-soluble proteins expressed by strains 43895OR and 43895 using one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis and identified two differentially expressed proteins. A 17-kDa protein unique to strain 43895OR was identified from matrix-assisted laser desorption ionization-time of flight analysis combined with mass spectrometry (MS) and tandem MS (MS/MS) as the curli subunit encoded by csgA. A <10-kDa protein, more highly expressed in strain 43895, was identified as the Lpp lipoprotein. Mutants of strain 43895OR with disruption of lpp, csgA, or both lpp and csgA were created and tested for changes in phenotype and function. The results of this study show that both Lpp and CsgA contribute to the observed colony morphology, Congo red binding, motility, and biofilm formation. We also show that both CsgA and Lpp are required by strain 43895OR for the invasion of cultured HEp-2 cells. These studies suggest that in strain 43895OR, the murein lipoprotein Lpp indirectly regulates CsgA expression through the CpxAR system by a posttranscriptional mechanism. PMID:19179421

  20. Real-time gastric motility monitoring using transcutaneous intraluminal impedance measurements (TIIM).

    PubMed

    Poscente, M D; Wang, G; Filip, D; Ninova, P; Yadid-Pecht, O; Andrews, C N; Mintchev, M P

    2014-02-01

    The stomach plays a critical role in digestion, processing ingested food mechanically and breaking it up into particles, which can be effectively and efficiently processed by the intestines. When the motility of the stomach is compromised, digestion is adversely affected. This can lead to a variety of disorders. Current diagnostic techniques for gastric motility disorders are seriously lacking, and are based more on eliminating other possibilities rather than on specific tests. Presently, gastric motility can be assessed by monitoring gastric emptying, food transit, intragastric pressures, etc. The associated tests are usually stationary and of relatively short duration. The present study proposes a new method of measuring gastric motility, utilizing the attenuation of an oscillator-induced electrical signal across the gastric tissue, which is modulated by gastric contractions. The induced high-frequency oscillator signal is generated within the stomach, and is picked up transluminally by cutaneous electrodes positioned on the abdominal area connected to a custom-designed data acquisition instrument. The proposed method was implemented in two different designs: first a transoral catheter was modified to emit the signal inside the stomach; and second, a gastric retentive pill was designed to emit the signal. Both implementations were applied in vivo on two mongrel dogs (25.50 kg and 25.75 kg). Gastric contractions were registered and quantitatively compared to recordings from force transducers sutured onto the serosa of the stomach. Gastric motility indices were calculated for each minute, with transluminal impedance measurements and the measurements from the force transducers showing statistically significant (p < 0.05) Pearson correlation coefficients (0.65 ± 0.08 for the catheter-based design and 0.77 ± 0.03 for the gastric retentive pill design). These results show that transcutaneous intraluminal impedance measurement has the potential with further research

  1. Intestinal Epithelial Toll-Like Receptor 4 Signaling Affects Epithelial Function and Colonic Microbiota and Promotes a Risk for Transmissible Colitis

    PubMed Central

    Dheer, Rishu; Santaolalla, Rebeca; Davies, Julie M.; Lang, Jessica K.; Phillips, Matthew C.; Pastorini, Cristhine; Vazquez-Pertejo, Maria T.

    2016-01-01

    Evidence obtained from gene knockout studies supports the role of Toll-like receptor 4 (TLR4) in intestinal inflammation and microbiota recognition. Increased epithelial TLR4 expression is observed in patients with inflammatory bowel disease. However, little is known of the effect of increased TLR4 signaling on intestinal homeostasis. Here, we examined the effect of increased TLR4 signaling on epithelial function and microbiota by using transgenic villin-TLR4 mice that overexpress TLR4 in the intestinal epithelium. Our results revealed that villin-TLR4 mice are characterized by increases in the density of mucosa-associated bacteria and bacterial translocation. Furthermore, increased epithelial TLR4 signaling was associated with an impaired epithelial barrier, altered expression of antimicrobial peptide genes, and altered epithelial cell differentiation. The composition of the colonic luminal and mucosa-associated microbiota differed between villin-TLR4 and wild-type (WT) littermates. Interestingly, WT mice cohoused with villin-TLR4 mice displayed greater susceptibility to acute colitis than singly housed WT mice did. The results of this study suggest that epithelial TLR4 expression shapes the microbiota and affects the functional properties of the epithelium. The changes in the microbiota induced by increased epithelial TLR4 signaling are transmissible and exacerbate dextran sodium sulfate-induced colitis. Together, our findings imply that host innate immune signaling can modulate intestinal bacteria and ultimately the host's susceptibility to colitis. PMID:26755160

  2. Coumestrol decreases intestinal alkaline phosphatase activity in post-delivery mice but does not affect vitamin D receptor and calcium channels in post-delivery and neonatal mice.

    PubMed

    Kirihata, Yuka; Kawarabayashi, Tetsu; Imanishi, Satoshi; Sugimoto, Miki; Kume, Shin-Ichi

    2008-02-01

    In this study, we investigated the effects of administration of coumestrol during pregnancy on calcium (Ca) metabolism in post-delivery maternal and neonatal mice. From 6.5 to 16.5 days post coitus (dpc), pregnant females were administered daily doses of coumestrol (200 microg/kg body weight/day). One day after parturition, blood samples and the kidneys, liver, jejunum and duodenum were obtained from each of maternal mouse, and blood samples and the kidneys and liver were obtained from neonatal mice. Coumestrol did not have any significant effect on the Ca and inorganic phosphorus concentrations in the sera of the maternal and neonatal mice. No notable effects of coumestrol were observed in relation to Vitamin D receptor expression in the maternal and neonatal mice by immunohistochemical analysis. Coumestrol did not affect the Vitamin D receptor and epithelial calcium channel and 2 mRNA levels in any of the organs investigated. Enzyme histochemical analysis showed that coumestrol decreased intestinal alkaline phosphatase activity in the maternal jejunum and duodenum. In the duodenum, coumestrol decreased expression of intestinal alkaline phosphatase, c-fos and vascular endothelial growth factor at the mRNA level. However, we did not observe any significant effects of coumestrol on the expression of these genes. In conclusion, coumestrol decreased intestinal alkaline phosphatase activity in the small intestines of maternal mice at the level used in the present study, and the mechanisms underlying this effect are different for the jejunum and duodenum. PMID:18160770

  3. Pediatric Gastrointestinal Motility Disorders: Challenges and a Clinical Update

    PubMed Central

    Chumpitazi, Bruno

    2008-01-01

    Pediatric gastrointestinal motility disorders are common and can range from relatively benign conditions such as functional constipation to more serious disorders such as achalasia, Hirschsprung disease, and intestinal pseudoobstruction. Performing and interpreting motility evaluations in children presents unique challenges and is complicated by a dearth of control information, underlying gastrointestinal developmental maturation, technical challenges (eg, catheter size limitations), and patient cooperation. Primary diseases such as congenital pseudoobstruction or Hirschsprung disease occur more often in children, but as with adults, abnormal motility may be secondary to other processes. Diagnostic studies include radiographic studies, manometry, breath testing, myoelectrical testing, and histologic evaluation. Although recent advances in technology, genetics, and biology are making an important impact and have allowed for a better understanding of the pathophysiology and therapy of gastrointestinal motility disorders in children, further research and new therapeutic agents are needed. PMID:21904491

  4. Vegetable lipid sources affect in vitro biosynthesis of triacylglycerols and phospholipids in the intestine of sea bream (Sparus aurata).

    PubMed

    Caballero, Maria José; Gallardo, Germán; Robaina, Lidia; Montero, Daniel; Fernández, Antonio; Izquierdo, Marisol

    2006-03-01

    Despite the good growth performance of several fish species when dietary fish oil is partly replaced by vegetable oils, recent studies have reported several types of intestinal morphological alterations in cultured fish fed high contents of vegetable lipid sources. However, the physiological process implied in these morphological changes have not been clarified yet, since alterations in the physiological mechanisms involved in the different processes of lipid absorption could be responsible for such gut morphological features. The objective of the present study was to investigate the activities of reacylation pathways in fish, the glycerol-3-phosphate and the monoacylglycerol pathways, in order to clarify the intestinal triacylglycerol (TAG) and phospholipid biosynthesis to better understand the morphological alterations observed in the intestine of fish fed vegetable oils. Intestinal microsomes of sea bream fed different lipid sources (fish, soyabean and rapeseed oils) at three different inclusion levels were isolated and incubated with L-[(14)C(U)]glycerol-3-phosphate and [1-(14)C]palmitoyl CoA. The results showed that in this fish species the glycerol-3-phosphate pathway is mainly involved in phospholipid synthesis, whereas TAG synthesis is mainly mediated by the monoacylglycerol pathway. Feeding with rapeseed oil reduced the reacylation activity in both pathways, explaining the high accumulation of lipid droplets in the supranuclear portion of the intestinal epithelium, whereas soyabean oil enhanced phosphatidylcholine synthesis, being associated with the increase in VLDL found in previous studies.

  5. [Disorders of intestinal innervation as a possible cause for chronic constipation].

    PubMed

    Wedel, T; Roblick, U; Gleiss, J; Ott, V; Eggers, R; Kühnel, W; Krammer, H J

    1999-01-01

    The gastrointestinal tract contains the largest amount of nerve cells apart from the central nervous system constituting together with glial cells the enteric nervous system (ENS). The morphology of the ENS is characterized by intramurally located ganglionated and non-ganglionated plexus of different structure. The diversity of neurotransmitters synthesized by the different nerve cell types as well as the complex neuronal circuits establish the basis for the mediation of a coordinated intestinal motility. Subsequently abnormalities of the ENS may cause severe constipation. The most acknowledged intestinal innervation disorder represents aganglionosis (Hirschsprung's disease) characterized by the absence of intramural nerve cells and the hypertrophy of nerve fiber bundles within the affected intestinal segment. Non-aganglionic intestinal innervation disorders include intestinal neuronal dysplasia (IND), hypoganglionosis and heterotopic ganglia. The pathogenesis of intestinal neuronal malformations is mainly attributed to development disorders of the ENS, in part caused by genetic defects. Furthermore, the ENS can sustain damage during the postnatal period by ischemic, inflammatory, autoimmunological processes or neurotoxic agents. The histopathological diagnosis of intestinal innervation disorders is achieved by enzyme- and immunohistochemical methods. The examination of the ENS can be carried out on mucosal, deep submucosal or full-thickness biopsies using serial transverse sections as well as on intestinal whole-mount preparations allowing a three-dimensional demonstration and assessment of the intramural plexus. Structural abnormalities of the myenteric and submucosal plexus and an abnormal content of neurotransmitters have been considered to be responsible for primary chronic constipation. However, until now no unified pathophysiological concept has been established due to the partly contradictory findings. Therefore, an important goal in patients with chronic

  6. Assessment of the Effect of Intestinal Permeability Probes (Lactulose And Mannitol) and Other Liquids on Digesta Residence Times in Various Segments of the Gut Determined by Wireless Motility Capsule: A Randomised Controlled Trial

    PubMed Central

    Sequeira, Ivana R.; Lentle, Roger G.; Kruger, Marlena C.; Hurst, Roger D.

    2015-01-01

    Background Whilst the use of the mannitol/lactulose test for intestinal permeability has been long established it is not known whether the doses of these sugars modify transit time Similarly it is not known whether substances such as aspirin that are known to increase intestinal permeability to lactulose and mannitol and those such as ascorbic acid which are stated to be beneficial to gastrointestinal health also influence intestinal transit time. Methods Gastric and intestinal transit times were determined with a SmartPill following consumption of either a lactulose mannitol solution, a solution containing 600 mg aspirin, a solution containing 500 mg of ascorbic acid or an extract of blackcurrant, and compared by doubly repeated measures ANOVA with those following consumption of the same volume of a control in a cross-over study in six healthy female volunteers. The dominant frequencies of cyclic variations in gastric pressure recorded by the Smartpill were determined by fast Fourier transforms. Results The gastric transit times of lactulose mannitol solutions, of aspirin solutions and of blackcurrant juice did not differ from those of the control. The gastric transit times of the ascorbic acid solutions were significantly shorter than those of the other solutions. There were no significant differences between the various solutions either in the total small intestinal or colonic transit times. The intraluminal pHs during the initial quartiles of the small intestinal transit times were lower than those in the succeeding quartiles. This pattern did not vary with the solution that was consumed. The power of the frequencies of cyclic variation in intragastric pressure recorded by the Smartpill declined exponentially with increase in frequency and did not peak at the reported physiological frequencies of gastric contractile activity. Conclusions Whilst the segmental residence times were broadly similar to those using other methods, the high degree of variation between

  7. Axonemal motility in Chlamydomonas.

    PubMed

    Wakabayashi, Ken-ichi; Kamiya, Ritsu

    2015-01-01

    Motile cilia and flagella rapidly propagate bending waves and produce water flow over the cell surface. Their function is important for the physiology and development of various organisms including humans. The movement is based on the sliding between outer doublet microtubules driven by axonemal dyneins, and is regulated by various axonemal components and environmental factors. For studies aiming to elucidate the mechanism of cilia/flagella movement and regulation, Chlamydomonas is an invaluable model organism that offers a variety of mutants. This chapter introduces standard methods for studying Chlamydomonas flagellar motility including analysis of swimming paths, measurements of swimming speed and beat frequency, motility reactivation in demembranated cells (cell models), and observation of microtubule sliding in disintegrating axonemes. Most methods may be easily applied to other organisms with slight modifications of the medium conditions.

  8. Cell motility on nanotopography

    NASA Astrophysics Data System (ADS)

    Kimura, Masahiro; Tsai, Irene; Green, Angelo; Jacobson, Bruce; Russell, Thomas

    2003-03-01

    Cell motility is strongly influenced by the structure of the substratum. Understanding cells motility on a surface has significant applications both in vivo and in vitro applications, such as biological sensors and hip replacement. A gradient surface is used to study the effect of the lateral nanotopography on cell motility. A gradient surface is generated by block copolymer and homopolymer blends, where the concentration of the components varies uniformly across the surface. The two homopolymers phase separate on the micron scale and this length scale gradually decrease to the nanoscopic, i.e. microphase separation of the diblock, as the copolymer concentration increases. Quantitative analysis of the speed of cell migration is correlated to the lateral length scale of the surface.

  9. Dietary supplementation with the probiotic Lactobacillus fermentum I5007 and the antibiotic aureomycin differentially affects the small intestinal proteomes of weanling piglets.

    PubMed

    Wang, Xiaoqiu; Yang, Fang; Liu, Chuang; Zhou, Huaijun; Wu, Guoyao; Qiao, Shiyan; Li, Defa; Wang, Junjun

    2012-01-01

    Antibiotics have long been used in animal production and medication to alleviate weaning stress. However, due to the concerns over food safety and human health, its use in animal production has been prohibited in many countries. Therefore, there is growing interest in developing alternative additives, such as a probiotic Lactobacillus. In this study, a proteomic approach coupled with biochemical analysis was applied to investigate alterations of proteomes in the small intestinal mucosa of weanling piglets after a 13-d period of feeding with supplemental L. fermentum I5007 or aureomycin (an antibiotic). We indentified 27 differentially expressed protein spots that participated in 7 key biological processes, including: 1) energy metabolism; 2) lipid metabolism; 3) protein synthesis; 4) cell structure and mobility; 5) cellular proliferation and apoptosis; 6) immune response; and 7) stress response and detoxification. Both L. fermentum I5007 and aureomycin decreased the expression of proteins related to apoptosis, stress response, and increased the expression of proteins related to detoxification in the gastrointestinal (GI) tract of weanling piglets. L. fermentum I5007 exhibited additional effects in alleviating weaning stress syndrome by enhancing the levels of proteins involved in energy metabolism, lipid metabolism, cell structure and mobility, protein synthesis, and immune response, thereby facilitating cellular proliferation and depressing apoptosis. In contrast, aureomycin reduced the levels of proteins related to energy metabolism, protein synthesis, cell structure, motility, and immunity. These novel findings have important implications for understanding the mechanisms whereby L. fermentum I5007 can improve the GI health of postweaning piglets. PMID:22113866

  10. Influence of the Enteric Nervous System on Gut Motility Patterns in Zebrafish

    NASA Astrophysics Data System (ADS)

    Baker, Ryan; Ganz, Julia; Melancon, Ellie; Eisen, Judith; Parthasarathy, Raghuveer

    The enteric nervous system (ENS), composed of diverse neuronal subtypes and glia, regulates essential gut functions including motility, secretion, and homeostasis. In humans and animals, decreased numbers of enteric neurons lead to a variety of types of gut dysfunction. However, surprisingly little is known about how the number, position, or subtype of enteric neurons affect the regulation of gut peristalsis, due to the lack of good model systems and the lack of tools for the quantitative characterization of gut motion. We have therefore developed a method of quantitative spatiotemporal mapping using differential interference contrast microscopy and particle image velocimetry, and have applied this to investigate intestinal dynamics in normal and mutant larval zebrafish. From movies of gut motility, we obtain a velocity vector field representative of gut motion, from which we can quantify parameters relating to gut peristalsis such as frequency, wave speed, deformation amplitudes, wave duration, and non-linearity of waves. We show that mutants with reduced neuron number have contractions that are more regular in time and reduced in amplitude compared to wild-type (normal) fish. We also show that feeding fish before their yolk is consumed leads to stronger motility patterns. We acknowledge support from NIH awards P50 GM098911 and P01 HD022486.

  11. Gastrointestinal motility revisited: The wireless motility capsule

    PubMed Central

    Farmer, Adam D; Scott, S Mark

    2013-01-01

    Introduction The wireless motility capsule (WMC) is a novel ambulatory technology that concurrently measures intraluminal pH, temperature, and pressure as it traverses the gastrointestinal tract. Objectives We aim to provide a concise summary of the WMC, detailing the procedure for its administration and the parameters it records. We also review the evidence that has validated the WMC against other methods currently regarded as ‘gold standard’. Conclusions The WMC offers a number of advantages over and above current techniques, especially with respect to patient tolerability, safety, and standardization. The WMC represents a considerable enhancement of the researchers’ and clinicians’ investigatory armamentarium. If this technology becomes widely adopted, coupled with international consensus upon the interpretation of physiological data derived therein, it may herald a new and exciting era in gastrointestinal physiology. PMID:24917991

  12. Feed supplemented with organic acids does not affect starch digestibility, nor intestinal absorptive or secretory function in broiler chickens.

    PubMed

    Ruhnke, I; Röhe, I; Goodarzi Boroojeni, F; Knorr, F; Mader, A; Hafeez, A; Zentek, J

    2015-04-01

    The current study aimed to determine the impact of acidified feed on apparent ileal starch digestibility, intestinal transport and barrier function and intestinal glucose transporter expression. The experiment included a control group and a treatment group with broilers fed a standard diet without or with 1.5% of a commercial organic acid product (64% formic acid, 25% propionic acid, 11% water). Broilers were fed with the experimental diets from hatching until days 32-35. Starch digestibility was determined using 0.2% titanium dioxide as ingestible marker. Gene expressions of the intestinal sodium glucose transporter 1 (SGLT-1) and glucose transporter 2 (GLUT-2) were analysed using qPCR analysis. Additionally, SGLT-1 function and chloride secretion were analysed in Ussing chamber experiments. Jejunal samples were sequentially exposed to 10 mm glucose, 100 μm phloridzin, 100 μm histamine and 100 μm carbachol. Apparent ileal starch digestibility (±SEM) of the control group (97.5 ± 0.35%) and the acid-treated group (97.0 ± 0.59%) did not differ (p = 0.674). The mean tissue conductance of intestinal samples obtained from the control group and the treatment group was similar [10.6 mS/cm(2) (±0.68) and 9.4 mS/cm(2) (±0.80) respectively (p = 0.147)]. The mean short-circuit currents (ΔIsc ) of the samples exposed to glucose, phloridzin, histamine and carbachol did not differ (p > 0.05). Additionally, no differences in the expression of SGLT-1 and GLUT-2 could be observed (p = 0.942, p = 0.413). Based on this study, the consumption of feed supplemented with organic acids was not associated with effects on ileal starch digestibility and functional traits of jejunal tissues, indicating that these additives have no major impact on the small intestinal function in broilers.

  13. Utilization of rye as energy source affects bacterial translocation, intestinal viscosity, microbiota composition, and bone mineralization in broiler chickens.

    PubMed

    Tellez, Guillermo; Latorre, Juan D; Kuttappan, Vivek A; Kogut, Michael H; Wolfenden, Amanda; Hernandez-Velasco, Xochitl; Hargis, Billy M; Bottje, Walter G; Bielke, Lisa R; Faulkner, Olivia B

    2014-01-01

    Two independent trials were conducted to evaluate the utilization of rye as energy source on bacterial translocation (BT), intestinal viscosity, gut integrity, gut microbiota composition, and bone mineralization, when compared with a traditional cereal (corn) in broiler chickens. In each experiment, day-of-hatch, broiler chickens were randomly assigned to either a corn or a rye diet (n = 20 chickens/group). At 10 d of age, in both experiments, 12 chickens/group were randomly selected, and given an oral gavage dose of fluorescein isothiocyanate dextran (FITC-d). After 2.5 h of oral gavage, blood samples were collected to determine the passage of FITC-d. The liver was collected from each bird to evaluate BT. Duodenum, ileum, and cecum gut sections were collected to evaluate intestinal viscosity and to enumerate gut microbiota. Tibias were collected for observation of bone parameters. Broilers fed with rye showed increased (p < 0.05) intestinal viscosity, BT, and serum FITC-d. Bacterial enumeration revealed that chickens fed with rye had increased the number of total lactic acid bacteria in all three sections of the gastrointestinal tract evaluated when compared to chickens fed with corn. Chickens fed with rye also had significantly higher coliforms in duodenum and ileum, whereas the total number of anaerobes increased only in duodenum. A significant reduction in bone strength and bone mineralization was observed in chickens fed with rye when compared with corn fed chickens. In conclusion, rye evoked mucosal damage in chickens that alter the intestinal viscosity, increased leakage through the intestinal tract, and altered the microbiota composition as well as bone mineralization. Studies to evaluate dietary inclusion of selected DFM candidates that produce exogenous enzymes in rye fed chickens are currently being evaluated.

  14. Overexpression of Peroxiredoxin 4 Affects Intestinal Function in a Dietary Mouse Model of Nonalcoholic Fatty Liver Disease

    PubMed Central

    Noguchi, Hirotsugu; Mazaki, Yuichi; Kurahashi, Toshihiro; Izumi, Hiroto; Wang, Ke-Yong; Guo, Xin; Uramoto, Hidetaka; Kohno, Kimitoshi; Taniguchi, Hatsumi; Tanaka, Yoshiya; Fujii, Junichi; Sasaguri, Yasuyuki; Tanimoto, Akihide; Nakayama, Toshiyuki

    2016-01-01

    Background Accumulating evidence has shown that methionine- and choline-deficient high fat (MCD+HF) diet induces the development of nonalcoholic fatty liver disease (NAFLD), in which elevated reactive oxygen species play a crucial role. We have reported that peroxiredoxin 4 (PRDX4), a unique secretory member of the PRDX antioxidant family, protects against NAFLD progression. However, the detailed mechanism and potential effects on the intestinal function still remain unclear. Methods & Results Two weeks after feeding mice a MCD+HF diet, the livers of human PRDX4 transgenic (Tg) mice exhibited significant suppression in the development of NAFLD compared with wild-type (WT) mice. The serum thiobarbituric acid reactive substances levels were significantly lower in Tg mice. In contrast, the Tg small intestine with PRDX4 overexpression showed more suppressed shortening of total length and villi height, and more accumulation of lipid in the jejunum, along with lower levels of dihydroethidium binding. The enterocytes exhibited fewer apoptotic but more proliferating cells, and inflammation was reduced in the mucosa. Furthermore, the small intestine of Tg mice had significantly higher expression of cholesterol absorption-regulatory factors, including liver X receptor-α, but lower expression of microsomal triglyceride-transfer protein. Conclusion Our present data provide the first evidence of the beneficial effects of PRDX4 on intestinal function in the reduction of the severity of NAFLD, by ameliorating oxidative stress-induced local and systemic injury. We can suggest that both liver and intestine are spared, to some degree, by the antioxidant properties of PRDX4. PMID:27035833

  15. Gastrointestinal motility and functional gastrointestinal diseases.

    PubMed

    Kusano, Motoyasu; Hosaka, Hiroko; Kawada, Akiyo; Kuribayashi, Shiko; Shimoyama, Yasuyuki; Zai, Hiroaki; Kawamura, Osamu; Yamada, Masanobu

    2014-01-01

    Digestive tract motility patterns are closely related to the pathophysiology of functional gastrointestinal diseases (FGID), and these patterns differ markedly between the interdigestive period and the postprandial period. The characteristic motility pattern in the interdigestive period is so-called interdigestive migrating contraction (IMC). IMCs have a housekeeping role in the intestinal tract, and could also be related to FGID. IMCs arising from the stomach are called gastrointestinal IMCs (GI-IMC), while IMCs arising from the duodenum without associated gastric contractions are called intestinal IMCs (I-IMC). It is thought that I-IMCs are abnormal in FGID. Transport of food residue to the duodenum via gastric emptying is one of the most important postprandial functions of the stomach. In patients with functional dyspepsia (FD), abnormal gastric emptying is a possible mechanism of gastric dysfunction. Accordingly, delayed gastric emptying has attracted attention, with prokinetic agents and herbal medicines often being administered in Japan to accelerate gastric emptying in patients who have anorexia associated with dyspepsia. Recently, we found that addition of monosodium L-glutamate (MSG) to a high-calorie liquid diet rich in casein promoted gastric emptying in healthy men. Therefore, another potential method of improving delayed gastric emptying could be activation of chemosensors that stimulate the autonomic nervous system of the gastrointestinal tract, suggesting a role for MSG in the management of delayed gastric emptying in patients with FD.

  16. The role of small intestinal bacterial overgrowth in Parkinson's disease.

    PubMed

    Fasano, Alfonso; Bove, Francesco; Gabrielli, Maurizio; Petracca, Martina; Zocco, Maria Assunta; Ragazzoni, Enzo; Barbaro, Federico; Piano, Carla; Fortuna, Serena; Tortora, Annalisa; Di Giacopo, Raffaella; Campanale, Mariachiara; Gigante, Giovanni; Lauritano, Ernesto Cristiano; Navarra, Pierluigi; Marconi, Stefano; Gasbarrini, Antonio; Bentivoglio, Anna Rita

    2013-08-01

    Parkinson's disease is associated with gastrointestinal motility abnormalities favoring the occurrence of local infections. The aim of this study was to investigate whether small intestinal bacterial overgrowth contributes to the pathophysiology of motor fluctuations. Thirty-three patients and 30 controls underwent glucose, lactulose, and urea breath tests to detect small intestinal bacterial overgrowth and Helicobacter pylori infection. Patients also underwent ultrasonography to evaluate gastric emptying. The clinical status and plasma concentration of levodopa were assessed after an acute drug challenge with a standard dose of levodopa, and motor complications were assessed by Unified Parkinson's Disease Rating Scale-IV and by 1-week diaries of motor conditions. Patients with small intestinal bacterial overgrowth were treated with rifaximin and were clinically and instrumentally reevaluated 1 and 6 months later. The prevalence of small intestinal bacterial overgrowth was significantly higher in patients than in controls (54.5% vs. 20.0%; P = .01), whereas the prevalence of Helicobacter pylori infection was not (33.3% vs. 26.7%). Compared with patients without any infection, the prevalence of unpredictable fluctuations was significantly higher in patients with both infections (8.3% vs. 87.5%; P = .008). Gastric half-emptying time was significantly longer in patients than in healthy controls but did not differ in patients based on their infective status. Compared with patients without isolated small intestinal bacterial overgrowth, patients with isolated small intestinal bacterial overgrowth had longer off time daily and more episodes of delayed-on and no-on. The eradication of small intestinal bacterial overgrowth resulted in improvement in motor fluctuations without affecting the pharmacokinetics of levodopa. The relapse rate of small intestinal bacterial overgrowth at 6 months was 43%. © 2013 Movement Disorder Society. PMID:23712625

  17. The role of small intestinal bacterial overgrowth in Parkinson's disease.

    PubMed

    Fasano, Alfonso; Bove, Francesco; Gabrielli, Maurizio; Petracca, Martina; Zocco, Maria Assunta; Ragazzoni, Enzo; Barbaro, Federico; Piano, Carla; Fortuna, Serena; Tortora, Annalisa; Di Giacopo, Raffaella; Campanale, Mariachiara; Gigante, Giovanni; Lauritano, Ernesto Cristiano; Navarra, Pierluigi; Marconi, Stefano; Gasbarrini, Antonio; Bentivoglio, Anna Rita

    2013-08-01

    Parkinson's disease is associated with gastrointestinal motility abnormalities favoring the occurrence of local infections. The aim of this study was to investigate whether small intestinal bacterial overgrowth contributes to the pathophysiology of motor fluctuations. Thirty-three patients and 30 controls underwent glucose, lactulose, and urea breath tests to detect small intestinal bacterial overgrowth and Helicobacter pylori infection. Patients also underwent ultrasonography to evaluate gastric emptying. The clinical status and plasma concentration of levodopa were assessed after an acute drug challenge with a standard dose of levodopa, and motor complications were assessed by Unified Parkinson's Disease Rating Scale-IV and by 1-week diaries of motor conditions. Patients with small intestinal bacterial overgrowth were treated with rifaximin and were clinically and instrumentally reevaluated 1 and 6 months later. The prevalence of small intestinal bacterial overgrowth was significantly higher in patients than in controls (54.5% vs. 20.0%; P = .01), whereas the prevalence of Helicobacter pylori infection was not (33.3% vs. 26.7%). Compared with patients without any infection, the prevalence of unpredictable fluctuations was significantly higher in patients with both infections (8.3% vs. 87.5%; P = .008). Gastric half-emptying time was significantly longer in patients than in healthy controls but did not differ in patients based on their infective status. Compared with patients without isolated small intestinal bacterial overgrowth, patients with isolated small intestinal bacterial overgrowth had longer off time daily and more episodes of delayed-on and no-on. The eradication of small intestinal bacterial overgrowth resulted in improvement in motor fluctuations without affecting the pharmacokinetics of levodopa. The relapse rate of small intestinal bacterial overgrowth at 6 months was 43%. © 2013 Movement Disorder Society.

  18. Somatostatin, substance P and calcitonin gene-related peptide-positive intramural nerve structures of the human large intestine affected by carcinoma.

    PubMed

    Godlewski, Janusz; Kaleczyc, Jerzy

    2010-09-30

    The aim of this study was to investigate the arrangement and chemical coding of enteric nerve structures in the human large intestine affected by cancer. Tissue samples comprising all layers of the intestinal wall were collected during surgery form both morphologically unchanged and pathologically altered segments of the intestine (n=15), and fixed by immersion in buffered paraformaldehyde solution. The cryostat sections were processed for double-labelling immunofluorescence to study the distribution of the intramural nerve structures (visualized with antibodies against protein gene-product 9.5) and their chemical coding using antibodies against somatostatin (SOM), substance P (SP) and calcitonin gene-related peptide (CGRP). The microscopic observations revealed distinct morphological differences in the enteric nerve system structure between the region adjacent to the cancer invaded area and the intact part of the intestine. In general, infiltration of the cancer tissue resulted in the gradual (depending on the grade of invasion) first decomposition and reduction to final partial or complete destruction and absence of the neuronal elements. A comparative analysis of immunohistochemically labeled sections (from the unchanged and pathologically altered areas) revealed a statistically significant decrease in the number of CGRP-positive neurons and nerve fibres in both submucous and myenteric plexuses in the transitional zone between morphologically unchanged and cancer-invaded areas. In this zone, a decrease was also observed in the density of SP-positive nerve fibres in all intramural plexuses. Conversely, the investigations demonstrated statistically insignificant differences in number of SP- and SOM-positive neurons and a similar density of SOM-positive nerve fibres in the plexuses of the intact and pathologically changed areas. The differentiation between the potential adaptive changes in ENS or destruction of its elements by cancer invasion should be a subject of

  19. Modeling collective cell motility

    NASA Astrophysics Data System (ADS)

    Rappel, Wouter-Jan

    Eukaryotic cells often move in groups, a critical aspect of many biological and medical processes including wound healing, morphogenesis and cancer metastasis. Modeling can provide useful insights into the fundamental mechanisms of collective cell motility. Constructing models that incorporate the physical properties of the cells, however, is challenging. Here, I discuss our efforts to build a comprehensive cell motility model that includes cell membrane properties, cell-substrate interactions, cell polarity, and cell-cell interaction. The model will be applied to a variety of systems, including motion on micropatterned substrates and the migration of border cells in Drosophila. This work was supported by NIH Grant No. P01 GM078586 and NSF Grant No. 1068869.

  20. [Esophageal motility disorders].

    PubMed

    Dughera, L; Battaglia, E; Emanuelli, G

    2001-09-01

    Esophageal motility abnormalities are usually diagnosed when esophageal manometry is performed in patients with unexplained non-cardiac chest pain, non obstructive dysphagia or as a part of the preoperative evaluation for surgery of gastroesophageal reflux. Classification of these abnormalities has been a subject of controversy. These esophageal contraction abnormalities can be separated manometrically from the motor pattern seen in normal subjects, however, their clinical relevance is still unclear and debated. Many patients demonstrate motility abnormalities in the manometry laboratories, but may lack correlation with their presenting symptoms. Medical treatment can decrease symptoms particularly chest pain or acid reflux but there is no significant changes in the manometric patterns. Such motor abnormalities may not reflect a true disease state, but they could be markers of other abnormalities and they can modify the initial manometric findings in time.

  1. An ocular motility conundrum

    PubMed Central

    McElnea, Elizabeth Margaret; Stephenson, Kirk; Lanigan, Bernie; Flitcroft, Ian

    2014-01-01

    Two siblings, an 11-year-old boy and a 7-year-old girl presented with bilateral symmetrical ptosis and limited eye movements. Having already been reviewed on a number of occasions by a variety of specialists in multiple hospital settings a diagnosis of their ocular motility disorder had remained elusive. We describe their cases, outline the differential diagnosis and review the investigations performed which were influential in finally making a diagnosis. PMID:25349186

  2. Dietary inulin intake and age can significantly affect intestinal absorption of calcium and magnesium in rats: a stable isotope approach

    PubMed Central

    Coudray, Charles; Rambeau, Mathieu; Feillet-Coudray, Christine; Tressol, Jean Claude; Demigne, Christian; Gueux, Elyett; Mazur, Andrzej; Rayssiguier, Yves

    2005-01-01

    Background previous studies have shown that non-digestible inulin-type fructan intake can increase intestinal mineral absorption in both humans and animals. However, this stimulatory effect on intestinal absorption may depend on experimental conditions such as duration of fermentable fiber intake, mineral diet levels and animals' physiological status, in particular their age. Objectives the aim of this study was to determine the effect of inulin intake on Ca and Mg absorption in rats at different age stages. Methods eighty male Wistar rats of four different ages (2, 5, 10 and 20 months) were randomized into either a control group or a group receiving 3.75% inulin in their diet for 4 days and then 7.5% inulin for three weeks. The animals were fed fresh food and water ad libitum for the duration of the experiment. Intestinal absorption of Ca and Mg was determined by fecal monitoring using stable isotopic tracers. Ca and Mg status was also assessed. Results absorption of Ca and Mg was significantly lower in the aged rats (10 and 20 mo) than in the young and adult rat groups. As expected, inulin intake increased Ca and Mg absorption in all four rat groups. However, inulin had a numerically greater effect on Ca absorption in aged rats than in younger rats whereas its effect on Mg absorption remained similar across all four rat age groups. Conclusion the extent of the stimulatory effect of inulin on absorption of Ca may differ according to animal ages. Further studies are required to explore this effect over longer inulin intake periods, and to confirm these results in humans. PMID:16253138

  3. Dietary amino acid levels and feed restriction affect small intestinal development, mortality, and weight gain of male broilers.

    PubMed

    Wijtten, P J A; Hangoor, E; Sparla, J K W M; Verstegen, M W A

    2010-07-01

    This study investigated the effect of 2 different dietary amino acid treatments and feed restriction in early life versus a control treatment on development of the small intestine segments (weights), mortality, and broiler performance. Each treatment was applied to 6 cages with Ross 308 male broilers and to 6 cages with Cobb 500 male broilers with 24 birds per cage. A control treatment (100% ideal protein) was compared with a treatment with 30% extra ideal protein, a treatment with daily adjustment of the dietary amino acid level and profile, and a feed restriction treatment. The protein treatments were applied from 0 to 14 d of age. The feed restriction was applied from 4 to 21 d of age. Restriction was 15% from d 4 to 14 of age and diminished with equal daily steps thereafter to 5% at 21 d of age. Birds were weighed and dissected for evaluation of small intestine weights at 6, 9, 14, and 36 d of age. Feed intake restriction reduced leg problems in Ross and Cobb broilers. Extra dietary protein reduced leg problems in Ross broilers only. The present experiment does not show that small intestinal weight development is related to mortality. Thirty percent extra dietary ideal protein increased duodenum weight between 6 and 9 d of age. This was not further increased by the daily optimization of the dietary amino acid level and profile. The increased duodenum weights coincided with an improved BW gain. This indicates that duodenum weight may be important in facilitating BW gain in young broilers. Thus, it may be worthwhile to pay more attention to the relation between nutrition and duodenum weight and duodenum function in further studies. PMID:20548070

  4. Threonine Affects Intestinal Function, Protein Synthesis and Gene Expression of TOR in Jian Carp (Cyprinus carpio var. Jian)

    PubMed Central

    Feng, Lin; Peng, Yan; Wu, Pei; Hu, Kai; Jiang, Wei-Dan; Liu, Yang; Jiang, Jun; Li, Shu-Hong; Zhou, Xiao-Qiu

    2013-01-01

    This study aimed to investigate the effects of threonine (Thr) on the digestive and absorptive ability, proliferation and differentiation of enterocytes, and gene expression of juvenile Jian carp (Cyprinus carpio var. Jian). First, seven isonitrogenous diets containing graded levels of Thr (7.4–25.2 g/kg diet) were fed to the fishes for 60 days. Second, enterocyte proliferation and differentiation were assayed by culturing enterocytes with graded levels of Thr (0–275 mg/l) in vitro. Finally, enterocytes were cultured with 0 and 205 mg/l Thr to determine protein synthesis. The percent weight gain (PWG), specific growth rate, feed intake, feed efficiency, protein retention value, activities of trypsin, lipase and amylase, weights and protein contents of hepatopancreas and intestine, folds heights, activities of alkaline phosphatase (AKP), γ- glutamyl transpeptidase and Na+/K+-ATPase in all intestinal segments, glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT) activities in hepatopancreas, and 4E-BP2 gene expression in muscle, hepatopancreas and intestinal segments were significantly enhanced by Thr (p<0.05). However, the plasma ammonia concentration and TOR gene expression decreased (p<0.05). In vitro, Thr supplement significantly increased cell numbers, protein content, the activities of GOT, GPT, AKP and Na+/K+-ATPase, and protein synthesis rate of enterocytes, and decreased LDH activity and ammonia content in cell medium (p<0.05). In conclusion, Thr improved growth, digestive and absorptive capacity, enterocyte proliferation and differentiation, and protein synthesis and regulated TOR and 4E-BP2 gene expression in juvenile Jian carp. The dietary Thr requirement of juvenile Jian carp was 16.25 g/kg diet (51.3 g/kg protein) based on quadratic regression analysis of PWG. PMID:23922879

  5. Dietary sodium selenite affects host intestinal and systemic immune response and disease susceptibility to necrotic enteritis in commercial broilers.

    PubMed

    Xu, S Z; Lee, S H; Lillehoj, H S; Bravo, D

    2015-01-01

    1. This study was to evaluate the effects of supplementary dietary selenium (Se) given as sodium selenite on host immune response against necrotic enteritis (NE) in commercial broiler chickens. 2. Chicks were fed from hatching on a non-supplemented diet or diets supplemented with different levels of Se (0.25, 0.50, and 1.00 Se mg/kg). To induce NE, broiler chickens were orally infected with Eimeria maxima at 14 d of age and then with Clostridium perfringens 4 d later using our previously established NE disease model. 3. NE-associated clinical signs and host protective immunity were determined by body weight changes, intestinal lesion scores, and serum antibodies against α-toxin and necrotic enteritis B (NetB) toxin. The effects of dietary Se on the gene expression of pro-inflammatory cytokines e.g., interleukin (IL)-1β, IL-6, IL-8LITAF (lipopolysaccharide-induced TNFα-factor), tumour necrosis factor (TNF) SF15, and inducible nitric oxide synthase (iNOS), glutathione peroxidase 7 (GPx7), and avian β-defensins (AvBD) 6, 8, and 13 (following NE infection) were analysed in the intestine and spleen. 4. The results showed that dietary supplementation of newly hatched broiler chicks with 0.25 Se mg/kg from hatch significantly reduced NE-induced gut lesions compared with infected birds given a non-supplemented diet. The levels of serum antibody against the NetB toxin in the chicks fed with 0.25 and 0.50 mg/kg Se were significantly higher than the non-supplemented control group. The transcripts for IL-1β, IL-6, IL-8, iNOS, LITAF, and GPx7, as well as AvBD6, 8, and 13 were increased in the intestine and spleen of Se-supplemented groups, whereas transcript for TNFSF15 was decreased in the intestine. 5. It was concluded that dietary supplementation with optimum levels of Se exerted beneficial effects on host immune response to NE and reduced negative consequence of NE-induced immunopathology.

  6. Deoxynivalenol affects the composition of the basement membrane proteins and influences en route the migration of CD16(+) cells into the intestinal epithelium.

    PubMed

    Nossol, Constanze; Diesing, A K; Kahlert, S; Kersten, S; Kluess, J; Ponsuksili, S; Hartig, R; Wimmers, K; Dänicke, S; Rothkötter, H J

    2013-11-01

    The numerous pores in the basement membrane (BM) of the intestinal villi are essential for the communication of enterocytes with cells in the lamina propria, an important mechanism for the induction of intestinal immune responses. The intestinal epithelial barrier is affected by the mycotoxin deoxynivalenol (DON) from both the apical (luminal) and basolateral (serosal) side. The pig is the most susceptible species to the anorectic and immune-modulating effects of DON, which is most prevalent in crops. We analysed in pigs the effect of DON-contaminated feed on the composition and perforation of the BM and the presence of CD16(+) cells or their dendrites in the epithelium. In addition to in vivo experiments, in vitro studies were carried out. Using microarray analyses, the effects of DON on IPEC-J2 cells were studied with the focus on the BM. Our in vivo results showed in the control pigs: (1) a significant increased pore number (p ≤ 0.001) in the jejunum in comparison to ileum, (2) no difference in the pore size, and (3) comparable frequency of intraepithelial CD16(+) cells/dendrites in the jejunum and ileum. There was a marked trend that DON feeding increases: (1) the pore number in jejunum, and (2) the number of CD16(+) cells/dendrites in the epithelium (Tukey-Kramer; p = 0.055 and p = 0.067, respectively). The in vivo results were extended with microarray analyses of epithelial cell (IPEC-J2 cells). The down-regulation of genes like syndecan, fibulin 6 and BM-40 was observed. These proteins are important factors in the BM composition and in formation of pores. Our results provide evidence that already low basolateral concentrations of DON (50 ng/mL) influence the production of the BM protein laminin by epithelial cells. Thus, DON affects the composition of the BM.

  7. Characterization of Pro-Inflammatory Flagellin Proteins Produced by Lactobacillus ruminis and Related Motile Lactobacilli

    PubMed Central

    Neville, B. Anne; Forde, Brian M.; Claesson, Marcus J.; Darby, Trevor; Coghlan, Avril; Nally, Kenneth; Ross, R. Paul; O’Toole, Paul W.

    2012-01-01

    Lactobacillus ruminis is one of at least twelve motile but poorly characterized species found in the genus Lactobacillus. Of these, only L. ruminis has been isolated from mammals, and this species may be considered as an autochthonous member of the gastrointestinal microbiota of humans, pigs and cows. Nine L. ruminis strains were investigated here to elucidate the biochemistry and genetics of Lactobacillus motility. Six strains isolated from humans were non-motile while three bovine isolates were motile. A complete set of flagellum biogenesis genes was annotated in the sequenced genomes of two strains, ATCC25644 (human isolate) and ATCC27782 (bovine isolate), but only the latter strain produced flagella. Comparison of the L. ruminis and L. mali DSM20444T motility loci showed that their genetic content and gene-order were broadly similar, although the L. mali motility locus was interrupted by an 11.8 Kb region encoding rhamnose utilization genes that is absent from the L. ruminis motility locus. Phylogenetic analysis of 39 motile bacteria indicated that Lactobacillus motility genes were most closely related to those of motile carnobacteria and enterococci. Transcriptome analysis revealed that motility genes were transcribed at a significantly higher level in motile L. ruminis ATCC27782 than in non-motile ATCC25644. Flagellin proteins were isolated from L. ruminis ATCC27782 and from three other Lactobacillus species, while recombinant flagellin of aflagellate L. ruminis ATCC25644 was expressed and purified from E. coli. These native and recombinant Lactobacillus flagellins, and also flagellate L. ruminis cells, triggered interleukin-8 production in cultured human intestinal epithelial cells in a manner suppressed by short interfering RNA directed against Toll-Like Receptor 5. This study provides genetic, transcriptomic, phylogenetic and immunological insights into the trait of flagellum-mediated motility in the lactobacilli. PMID:22808200

  8. Local actions of trimebutine maleate in canine small intestine.

    PubMed

    Daniel, E E; Kostolanska, F; Allescher, H D; Ahmad, S; Fox, J E

    1988-06-01

    A study of the local actions of trimebutine (TMB) maleate and its N-diesmethyl metabolite (TMB-M) was carried out in the gastrointestinal tract of anesthetized dogs. In the unstimulated small intestine, but not in the stomach or colon, i.a. TMB and TMB-M caused activation of circular muscle. Like the activation by i.a. [Met5]-enkephalin, this was antagonized by naloxone. In field-stimulated segments of stomach and small intestine circular muscle, TMB or TMB-M, like dynorphin-1-13 or [Met5]-enkephalin, inhibited the phasic and tonic contractions which were mediated mostly by cholinergic, postganglionic nerves. However, the inhibitory effects of dynorphin-1-13 or [Met5]-enkephalin on small intestine were antagonized by naloxone whereas those of TMB sometimes or those of TMB-M usually were not. TMB or TMB-M did not affect responses to i.a. acetylcholine, but high doses reduced the contractile responses to subsequent field stimulation and excitatory responses to [Met5]-enkephalin. We concluded that the excitatory local actions of TMB or TMB-M on small intestine involved opioid receptors probably of the mu or delta types. Inhibitory local actions on nerve-mediated responses, however, may not have involved opioid receptors. Comparison of these data to results when TMB or TMB-M were given i.v. suggests that these agents also have peripheral actions to affect gastrointestinal motility at sites outside the gastrointestinal tract. PMID:2898521

  9. The Host Genotype and Environment Affect Strain Types of Bifidobacterium longum subsp. longum Inhabiting the Intestinal Tracts of Twins

    PubMed Central

    Zhang, Min; Hang, Xiaomin; Tan, Jing

    2015-01-01

    To investigate the influences of host genotype and environment on Bifidobacterium longum subsp. longum inhabiting human intestines at the strain level, six pairs of twins, divided into two groups (children and adults), were recruited. Each group consisted of two monozygotic (MZ) twin pairs and one dizygotic (DZ) twin pair. Child twins had been living together from birth, while adult twins had been living separately for 5 to 10 years. A total of 345 B. longum subsp. longum isolates obtained from 60 fecal samples from these twins were analyzed by multilocus sequence typing (MLST), and 35 sequence types (STs) were finally acquired. Comparison of strains within and between the twin pairs showed that no strains with identical STs were observed between unrelated individuals or within adult DZ twin pairs. Eight STs were found to be monophyletic, existing within MZ twins and child DZ twins. The similarity of strain types within child cotwins was significantly higher than that within adult cotwins, which indicated that environment was one of the important determinants in B. longum subsp. longum strain types inhabiting human intestines. However, although these differences between MZ and DZ twins were observed, it is still difficult to reach an exact conclusion about the impact of host genotype. This is mainly because of the limited number of subjects tested in the present study and the lack of strain types tracing in the same twin pairs from birth until adulthood. PMID:25956768

  10. Cellular mechanics and motility

    NASA Astrophysics Data System (ADS)

    Hénon, Sylvie; Sykes, Cécile

    2015-10-01

    The term motility defines the movement of a living organism. One widely known example is the motility of sperm cells, or the one of flagellar bacteria. The propulsive element of such organisms is a cilium(or flagellum) that beats. Although cells in our tissues do not have a flagellum in general, they are still able to move, as we will discover in this chapter. In fact, in both cases of movement, with or without a flagellum, cell motility is due to a dynamic re-arrangement of polymers inside the cell. Let us first have a closer look at the propulsion mechanism in the case of a flagellum or a cilium, which is the best known, but also the simplest, and which will help us to define the hydrodynamic general conditions of cell movement. A flagellum is sustained by cellular polymers arranged in semi-flexible bundles and flagellar beating generates cell displacement. These polymers or filaments are part of the cellular skeleton, or "cytoskeleton", which is, in this case, external to the cellular main body of the organism. In fact, bacteria move in a hydrodynamic regime in which viscosity dominates over inertia. The system is thus in a hydrodynamic regime of low Reynolds number (Box 5.1), which is nearly exclusively the case in all cell movements. Bacteria and their propulsion mode by flagella beating are our unicellular ancestors 3.5 billion years ago. Since then, we have evolved to form pluricellular organisms. However, to keep the ability of displacement, to heal our wounds for example, our cells lost their flagellum, since it was not optimal in a dense cell environment: cells are too close to each other to leave enough space for the flagella to accomplish propulsion. The cytoskeleton thus developed inside the cell body to ensure cell shape changes and movement, and also mechanical strength within a tissue. The cytoskeleton of our cells, like the polymers or filaments that sustain the flagellum, is also composed of semi-flexible filaments arranged in bundles, and also in

  11. Motility disorders in childhood.

    PubMed

    Milla, P J

    1998-12-01

    Motility disorders are very common in childhood, causing a number of gastrointestinal symptoms: recurrent vomiting, abdominal pain and distension, constipation and obstipation, and loose stools. The disorders result from disturbances of gut motor control mechanisms caused by either intrinsic disease of nerve and muscle, central nervous system dysfunction or perturbation of the humoral environment in which they operate. Intrinsic gut motor disease and central nervous system disorder are most usually congenital in origin, and alterations of the humoral environment acquired. Irritable bowel syndrome occurs in children as well as adults and is multifactorial in origin, with an interplay of psychogenic and organic disorders. PMID:10079906

  12. Maintenance of motility bias during cyanobacterial phototaxis.

    PubMed

    Chau, Rosanna Man Wah; Ursell, Tristan; Wang, Shuo; Huang, Kerwyn Casey; Bhaya, Devaki

    2015-04-01

    Signal transduction in bacteria is complex, ranging across scales from molecular signal detectors and effectors to cellular and community responses to stimuli. The unicellular, photosynthetic cyanobacterium Synechocystis sp. PCC6803 transduces a light stimulus into directional movement known as phototaxis. This response occurs via a biased random walk toward or away from a directional light source, which is sensed by intracellular photoreceptors and mediated by Type IV pili. It is unknown how quickly cells can respond to changes in the presence or directionality of light, or how photoreceptors affect single-cell motility behavior. In this study, we use time-lapse microscopy coupled with quantitative single-cell tracking to investigate the timescale of the cellular response to various light conditions and to characterize the contribution of the photoreceptor TaxD1 (PixJ1) to phototaxis. We first demonstrate that a community of cells exhibits both spatial and population heterogeneity in its phototactic response. We then show that individual cells respond within minutes to changes in light conditions, and that movement directionality is conferred only by the current light directionality, rather than by a long-term memory of previous conditions. Our measurements indicate that motility bias likely results from the polarization of pilus activity, yielding variable levels of movement in different directions. Experiments with a photoreceptor (taxD1) mutant suggest a supplementary role of TaxD1 in enhancing movement directionality, in addition to its previously identified role in promoting positive phototaxis. Motivated by the behavior of the taxD1 mutant, we demonstrate using a reaction-diffusion model that diffusion anisotropy is sufficient to produce the observed changes in the pattern of collective motility. Taken together, our results establish that single-cell tracking can be used to determine the factors that affect motility bias, which can then be coupled with

  13. Intestinal leiomyoma

    MedlinePlus

    Leiomyoma - intestine ... McLaughlin P, Maher MM. The duodenum and small intestine. In: Adam A, Dixon AK, Gillard JH, Schaefer- ... Roline CE, Reardon RF. Disorders of the small intestine. In: Marx JA, Hockberger RS, Walls RM, et ...

  14. Intestinal Cancer

    MedlinePlus

    ... connects your stomach to your large intestine. Intestinal cancer is rare, but eating a high-fat diet ... increase your risk. Possible signs of small intestine cancer include Abdominal pain Weight loss for no reason ...

  15. Pseudomonas aeruginosa Exhibits Sliding Motility in the Absence of Type IV Pili and Flagella▿ †

    PubMed Central

    Murray, Thomas S.; Kazmierczak, Barbara I.

    2008-01-01

    Pseudomonas aeruginosa exhibits swarming motility on 0.5 to 1% agar plates in the presence of specific carbon and nitrogen sources. We have found that PAO1 double mutants expressing neither flagella nor type IV pili (fliC pilA) display sliding motility under the same conditions. Sliding motility was inhibited when type IV pilus expression was restored; like swarming motility, it also decreased in the absence of rhamnolipid surfactant production. Transposon insertions in gacA and gacS increased sliding motility and restored tendril formation to spreading colonies, while transposon insertions in retS abolished motility. These changes in motility were not accompanied by detectable changes in rhamnolipid surfactant production or by the appearance of bacterial surface structures that might power sliding motility. We propose that P. aeruginosa requires flagella during swarming to overcome adhesive interactions mediated by type IV pili. The apparent dependence of sliding motility on environmental cues and regulatory pathways that also affect swarming motility suggests that both forms of motility are influenced by similar cohesive factors that restrict translocation, as well as by dispersive factors that facilitate spreading. Studies of sliding motility may be particularly well-suited for identifying factors other than pili and flagella that affect community behaviors of P. aeruginosa. PMID:18065549

  16. Intestinal gas dynamics: mechanisms and clinical relevance

    PubMed Central

    Azpiroz, F

    2005-01-01

    Patients with functional gut disorders, irritable bowel disease, and related syndromes frequently attribute their symptoms to intestinal gas. While patients are usually convinced of their interpretation, the doctor has few arguments to confirm or refute it, and in this context intestinal gas has become a myth. Studies of intestinal gas dynamics have demonstrated subtle dysfunctions in intestinal motility. Hopefully, extension of these studies may help both in the classification of patients complaining of gas symptoms based on pathophysiological mechanisms, and in identification of objective markers to test mechanistically oriented treatment options. PMID:15951528

  17. Intestinal gas dynamics: mechanisms and clinical relevance.

    PubMed

    Azpiroz, F

    2005-07-01

    Patients with functional gut disorders, irritable bowel disease, and related syndromes frequently attribute their symptoms to intestinal gas. While patients are usually convinced of their interpretation, the doctor has few arguments to confirm or refute it, and in this context intestinal gas has become a myth. Studies of intestinal gas dynamics have demonstrated subtle dysfunctions in intestinal motility. Hopefully, extension of these studies may help both in the classification of patients complaining of gas symptoms based on pathophysiological mechanisms, and in identification of objective markers to test mechanistically oriented treatment options.

  18. Inclusion of Chicory (Cichorium intybus L.) in Pigs' Diets Affects the Intestinal Microenvironment and the Gut Microbiota

    PubMed Central

    Liu, Haoyu; Ivarsson, Emma; Dicksved, Johan; Lundh, Torbjörn

    2012-01-01

    The content and composition of prebiotic plant fiber in the diet is important in promoting gut-related health. This study investigated the effects of the dietary inclusion of chicory forage and roots on the intestinal microenvironment of pigs. Thirty-seven-week-old pigs were fed 1 of 5 diets for 18 days, including a cereal-based control diet and 4 diets with the inclusion of 80 and 160 g kg−1 of body weight chicory forage (CF80 and CF160), 80 g kg−1 chicory root (CR80), and a mix of 80 g kg−1 forage and 80 g kg−1 chicory root (CFR). The animals maintained good performance and health irrespective of diet. Bacterial community structure and diversity in ileal and colonic samples was assessed using terminal restriction fragment length polymorphism (T-RFLP), combined with cloning and sequencing. Samples clustered perfectly according to gut segment with a higher bacterial diversity in colon than ileum. Distal ileum was dominated by lactic acid bacteria (LAB), and the relative amount of this group was increased by the CF160 and CFR diets. The colonic bacterial community was dominated by butyrate-producing bacteria and Prevotella. The increased relative abundance of butyrate-producing bacteria in the colon was positively correlated with the molar proportion of acetic acid and furthermore linked to the chicory forage diets (CF80 and CF160). Diets including chicory roots (CR80 and CFR) were correlated with a higher colonic abundance of Megasphaera elsdenii. The fermentation products and pH in digesta responded to diet type and were correlated with shifts in the microbiota, showing that chicory influences the intestinal microenvironment of pigs. PMID:22492453

  19. Berberine Improves Intestinal Motility and Visceral Pain in the Mouse Models Mimicking Diarrhea-Predominant Irritable Bowel Syndrome (IBS-D) Symptoms in an Opioid-Receptor Dependent Manner

    PubMed Central

    Pan, Qiuhui; Fichna, Jakub; Zheng, Lijun; Wang, Kesheng; Yu, Zhen; Li, Yongyu; Li, Kun; Song, Aihong; Liu, Zhongchen; Song, Zhenshun; Kreis, Martin

    2015-01-01

    Background and Aims Berberine and its derivatives display potent analgesic, anti-inflammatory and anticancer activity. Here we aimed at characterizing the mechanism of action of berberine in the gastrointestinal (GI) tract and cortical neurons using animal models and in vitro tests. Methods The effect of berberine was characterized in murine models mimicking diarrhea-predominant irritable bowel syndrome (IBS-D) symptoms. Then the opioidantagonists were used to identify the receptors involved. Furthermore, the effect of berberineon opioid receptors expression was established in the mouse intestine and rat fetal cortical neurons. Results In mouse models, berberine prolonged GI transit and time to diarrhea in a dose-dependent manner, and significantly reduced visceral pain. In physiological conditions the effects of berberine were mediated by mu- (MOR) and delta- (DOR) opioidreceptors; hypermotility, excessive secretion and nociception were reversed by berberine through MOR and DOR-dependent action. We also found that berberine increased the expression of MOR and DOR in the mouse bowel and rat fetal cortical neurons. Conclusion Berberine significantly improved IBS-D symptoms in animal models, possibly through mu- and delta- opioid receptors. Berberine may become a new drug candidate for the successful treatment of IBS-D in clinical conditions. PMID:26700862

  20. Sliding Motility in Mycobacteria

    PubMed Central

    Martínez, Asunción; Torello, Sandra; Kolter, Roberto

    1999-01-01

    Mycobacteria are nonflagellated gram-positive microorganisms. Previously thought to be nonmotile, we show here that Mycobacterium smegmatis can spread on the surface of growth medium by a sliding mechanism. M. smegmatis spreads as a monolayer of cells which are arranged in pseudofilaments by close cell-to-cell contacts, predominantly along their longitudinal axis. The monolayer moves away from the inoculation point as a unit with only minor rearrangements. No extracellular structures such as pili or fimbriae appear to be involved in this process. The ability to translocate over the surface correlates with the presence of glycopeptidolipids, a mycobacterium-specific class of amphiphilic molecules located in the outermost layer of the cell envelope. We present evidence that surface motility is not restricted to M. smegmatis but is also a property of the slow-growing opportunistic pathogen M. avium. This form of motility could play an important role in surface colonization by mycobacteria in the environment as well as in the host. PMID:10572138

  1. Spirochete motility and morpholgy

    NASA Astrophysics Data System (ADS)

    Charon, Nyles

    2004-03-01

    Spirochetes have a unique structure, and as a result their motility is different from that of other bacteria. These organisms can swim in a highly viscous, gel-like medium, such as that found in connective tissue, that inhibits the motility of most other bacteria. In spirochetes, the organelles for motility, the periplasmic flagella, reside inside the cell within the periplasmic space. A given periplasmic flagellum is attached only at one end of the cell, and depending on the species, may or may not overlap in the center of the cell. The number of periplasmic flagella varies from species to species. These structures have been shown to be directly involved in motility and function by rotating within the periplasmic space (1). The present talk focuses on the spirochete that causes Lyme disease, Borrelia burgdorferi. In many bacterial species, cell shape is usually dictated by the peptidoyglycan layer of the cell wall. In the first part of the talk, results will be presented that the morphology of B. burgdorferi is the result of a complex interaction between the cell cylinder and the internal periplasmic flagella resulting in a cell with a flat-wave morphology. Backward moving, propagating waves enable these bacteria to swim and translate in a given direction. Using targeted mutagenesis, we inactivated the gene encoding the major periplasmic flagellar filament protein FlaB. The resulting flaB mutants not only were non-motile, but were rod-shaped (2). Western blot analysis indicated that flaB was no longer synthesized, and electron microscopy revealed that the mutants were completely deficient in periplasmic flagella. Our results indicate that the periplasmic flagella of B. burgdorferi have a skeletal function. These organelles dynamically interact with the rod-shaped cell cylinder to enable the cell to swim, and to confer in part its flat-wave morphology The latter part of the talk concerns the basis for asymmetrical rotation of the periplasmic flagella of B

  2. [Motility of human spermatozoa (author's transl)].

    PubMed

    David, G; Serres, C; Escalier, D

    1981-01-01

    Microcinematography has permitted the analysis of human sperm motility and the definition of various parameters which can be used to characterize such movements. The locomotor apparatus of the sperm flagellum consists of an axoneme to which has been added the dense fibers and the fibrous sheath. A dysfunction of flagellar locomotion may be caused by mutations resulting in various structural defects of which the most common affect the dynein arms.

  3. The intestine is a blender

    NASA Astrophysics Data System (ADS)

    Yang, Patricia; Lamarca, Morgan; Kravets, Victoria; Hu, David

    According to the U.S. Department of Health and Human Services, digestive disease affects 60 to 70 million people and costs over 140 billion annually. Despite the significance of the gastrointestinal tract to human health, the physics of digestion remains poorly understood. In this study, we ask a simple question: what sets the frequency of intestinal contractions? We measure the frequency of intestinal contractions in rats, as a function of distance down the intestine. We find that intestines Contract radially ten times faster than longitudinally. This motion promotes mixing and, in turn, absorption of food products by the intestinal wall. We calculate viscous dissipation in the intestinal fluid to rationalize the relationship between frequency of intestinal contraction and the viscosity of the intestinal contents. Our findings may help to understand the evolution of the intestine as an ideal mixer.

  4. The intestine is a blender

    NASA Astrophysics Data System (ADS)

    Yang, Patricia; Lamarca, Morgan; Hu, David

    2015-11-01

    According to the U.S. Department of Health and Human Services, digestive disease affects 60 to 70 million people and costs over 140 billion annually. Despite the significance of the gastrointestinal tract to human health, the physics of digestion remains poorly understood. In this study, we ask a simple question: what sets the frequency of intestinal contractions? We measure the frequency of intestinal contractions in rats, as a function of distance down the intestine. We find that intestines contract radially ten times faster than longitudinally. This motion promotes mixing and, in turn, absorption of food products by the intestinal wall. We calculate viscous dissipation in the intestinal fluid to rationalize the relationship between frequency of intestinal contraction and the viscosity of the intestinal contents. Our findings may help to understand the evolution of the intestine as an ideal mixer.

  5. Processing of soybean meal and 00-rapeseed meal reduces protein digestibility and pig growth performance but does not affect nitrogen solubilization along the small intestine.

    PubMed

    Hulshof, T G; van der Poel, A F B; Hendriks, W H; Bikker, P

    2016-06-01

    An experiment was conducted to determine the effects of processing of soybean meal (SBM) and 00-rapeseed meal (RSM) on N solubilization in chyme, CP digestibility along the small intestine, metabolic load as determined by organ weight, body composition, and growth performance in growing pigs. The SBM and RSM were processed by secondary toasting (at 95°C for 30 min) in the presence of lignosulfonate, resulting in processed SBM (pSBM) and processed RSM (pRSM) as a model for overprocessed protein sources. Fifty-four growing pigs were each fed 1 of the 6 experimental diets. Four of the diets contained SBM, pSBM, RSM, or pRSM as the sole protein source. The remaining 2 experimental diets contained pSBM or pRSM and were supplemented with crystalline AA to the same standardized ileal digestible AA levels as the SBM or RSM diet. Pigs were slaughtered at 40 kg, and organ weights were recorded. The organs plus blood and empty carcass were analyzed for CP content. The small intestine was divided into 3 segments, and chyme samples were taken from the last meter of each segment. Chyme of the SBM, pSBM, RSM, and pRSM diets was centrifuged to separate the soluble and insoluble fractions, and N content was determined in the latter. The amount of insoluble N as a fraction of N in chyme at each small intestinal segment was not affected by processing. Diet type, comprising effects of processing and supplementing crystalline AA, affected ( < 0.05) the G:F and standardized ileal digestibility (SID) of CP. Processing reduced G:F from 0.56 to 0.38 for SBM and 0.49 to 0.40 for RSM, whereas supplementing crystalline AA increased G:F to the level of the SBM and RSM diets. Processing reduced the SID of CP from 87.2% to 69.2% for SBM and 71.0% to 52.2% for RSM. Diet type affected ( < 0.05) the CP content in the empty body, with processing reducing this content from 170 to 144 g/kg empty BW for SBM and 157 to 149 g/kg empty BW for RSM and supplementing crystalline AA restoring this content

  6. Intestinal transplantation in children with chronic intestinal pseudo-obstruction

    PubMed Central

    Sigurdsson, L; Reyes, J; Kocoshis, S; Mazariegos, G; Abu-Elmagd, K; Bueno, J; Di, L

    1999-01-01

    BACKGROUND—Children with chronic intestinal pseudo-obstruction (CIPO) often require total parenteral nutrition (TPN) which puts them at risk of liver failure and recurrent line infections. Intestinal transplantation has become a therapeutic option for TPN dependent children with intestinal failure who are failing management with TPN.
AIMS—To investigate the outcome of children with CIPO referred for intestinal transplantation.
METHODS—A retrospective review was carried out of records and diagnostic studies from 27 patients with CIPO referred for intestinal transplantation.
RESULTS—Five children were not listed for transplantation: two because of parental decision, two because of suspicion of Munchausen syndrome by proxy, and one because he tolerated enteral nutrition. Six are still TPN dependent and awaiting transplantation. Eight children died awaiting transplantation. Eight children underwent transplantation. Three died (two months, seven months, and four years after transplant). Five children are alive with a median follow up of 2.6 years (range two months to six years). All transplanted children were able to tolerate full enteral feedings. The postoperative course was complicated by dumping syndrome, Munchausen syndrome by proxy, narcotic withdrawal, and uncovering of achalasia. Conclusion—Intestinal transplantation may be a life saving procedure in children with CIPO. Early referral and thorough pretransplant evaluation are keys to successful transplantation.


Keywords: intestinal transplantation; small bowel transplantation; children; chronic intestinal pseudo-obstruction; small bowel motility; total parenteral nutrition PMID:10486367

  7. Intra-amniotic administration and dietary inulin affect the iron status and intestinal functionality of iron-deficient broiler chickens.

    PubMed

    Tako, E; Glahn, R P

    2012-06-01

    Inulin, a linear β-fructan, is present in a variety of plants, with relatively high levels of up to 20% in chicory root. It exhibits prebiotic properties and was shown to enhance mineral absorption. Our objectives were to assess the effect of intra-amniotic administration of inulin at 17 d of incubation on the iron status of broiler chicks (at hatch, 21 d) and to continue to monitor iron status with and without dietary inulin on these hatchlings for 42 d. The study included 3 prehatch treatment groups (n = 30): 1) inulin, inulin solution (4% inulin/0.85% saline); 2) control 1, untreated eggs; and 3) control 2, saline solution (0.85% saline). Solutions were injected into the naturally consumed amniotic fluid of 17-d-old chicken embryos (groups 1, 3). Upon hatch (93% hatchability), and from each group, 10 chicks were killed and their small intestine, liver, and cecum were removed for mRNA abundance of intestinal iron-related transporters, liver ferritin amounts, and bacterial analysis of cecal content, respectively. From the remaining chicks of each group, chicks were allocated to a standard corn-based diet (± 4% inulin, n = 10). During the trial, hemoglobin concentrations and body hemoglobin-Fe values were higher in the inulin group versus controls (P < 0.05). On d 42, birds were anesthetized and their duodenal loops were exposed. A nonocclusive catheter was inserted into the duodenal vein for blood sampling. A solution containing ⁵⁸Fe (0.1 mg of Fe/10 mM ascorbic acid) added to the digested diet sample was injected into the loop. Blood samples were collected every 5 min and for 90 min postinjection and analyzed by inductively coupled argon-plasma mass spectrometry for ⁵⁸Fe concentrations. At the end of the procedure, animals were killed and cecum contents and sections of the duodenum and liver were removed. Results showed that ⁵⁸Fe absorption rates were at times higher in the inulin group versus the other groups. Also, mRNA abundance of DMT1 (an Fe

  8. The effect of flagellar motor-rotor complexes on twitching motility in P. aeruginosa

    NASA Astrophysics Data System (ADS)

    Zhao, Kun; Utada, Andrew; Gibiansky, Maxsim; Xian, Wujing; Wong, Gerard

    2013-03-01

    P. aeruginosa is an opportunistic bacterium responsible for a broad range of biofilm infections. In order for biofilms to form, P. aeruginosa uses different types of surface motility. In the current understanding, flagella are used for swarming motility and type IV pili are used for twitching motility. The flagellum also plays important roles in initial surface attachment and in shaping the architectures of mature biofilms. Here we examine how flagella and pili interact during surface motility, by using cell tracking techniques. We show that the pili driven twitching motility of P. aeruginosa can be affected by the motor-rotor complexes of the flagellar system.

  9. Chronic intestinal pseudo-obstruction

    PubMed Central

    Antonucci, Alexandra; Fronzoni, Lucia; Cogliandro, Laura; Cogliandro, Rosanna F; Caputo, Carla; Giorgio, Roberto De; Pallotti, Francesca; Barbara, Giovanni; Corinaldesi, Roberto; Stanghellini, Vincenzo

    2008-01-01

    Chronic intestinal pseudo-obstruction (CIPO) is a severe digestive syndrome characterized by derangement of gut propulsive motility which resembles mechanical obstruction, in the absence of any obstructive process. Although uncommon in clinical practice, this syndrome represents one of the main causes of intestinal failure and is characterized by high morbidity and mortality. It may be idiopathic or secondary to a variety of diseases. Most cases are sporadic, even though familial forms with either dominant or recessive autosomal inheritance have been described. Based on histological features intestinal pseudo-obstruction can be classified into three main categories: neuropathies, mesenchymopathies, and myopathies, according on the predominant involvement of enteric neurones, interstitial cells of Cajal or smooth muscle cells, respectively. Treatment of intestinal pseudo-obstruction involves nutritional, pharmacological and surgical therapies, but it is often unsatisfactory and the long-term outcome is generally poor in the majority of cases. PMID:18494042

  10. Small intestinal bacterial overgrowth syndrome

    PubMed Central

    Bures, Jan; Cyrany, Jiri; Kohoutova, Darina; Förstl, Miroslav; Rejchrt, Stanislav; Kvetina, Jaroslav; Vorisek, Viktor; Kopacova, Marcela

    2010-01-01

    Human intestinal microbiota create a complex polymicrobial ecology. This is characterised by its high population density, wide diversity and complexity of interaction. Any dysbalance of this complex intestinal microbiome, both qualitative and quantitative, might have serious health consequence for a macro-organism, including small intestinal bacterial overgrowth syndrome (SIBO). SIBO is defined as an increase in the number and/or alteration in the type of bacteria in the upper gastrointestinal tract. There are several endogenous defence mechanisms for preventing bacterial overgrowth: gastric acid secretion, intestinal motility, intact ileo-caecal valve, immunoglobulins within intestinal secretion and bacteriostatic properties of pancreatic and biliary secretion. Aetiology of SIBO is usually complex, associated with disorders of protective antibacterial mechanisms (e.g. achlorhydria, pancreatic exocrine insufficiency, immunodeficiency syndromes), anatomical abnormalities (e.g. small intestinal obstruction, diverticula, fistulae, surgical blind loop, previous ileo-caecal resections) and/or motility disorders (e.g. scleroderma, autonomic neuropathy in diabetes mellitus, post-radiation enteropathy, small intestinal pseudo-obstruction). In some patients more than one factor may be involved. Symptoms related to SIBO are bloating, diarrhoea, malabsorption, weight loss and malnutrition. The gold standard for diagnosing SIBO is still microbial investigation of jejunal aspirates. Non-invasive hydrogen and methane breath tests are most commonly used for the diagnosis of SIBO using glucose or lactulose. Therapy for SIBO must be complex, addressing all causes, symptoms and complications, and fully individualised. It should include treatment of the underlying disease, nutritional support and cyclical gastro-intestinal selective antibiotics. Prognosis is usually serious, determined mostly by the underlying disease that led to SIBO. PMID:20572300

  11. Intestinal injury following liver transplantation was mediated by TLR4/NF-κB activation-induced cell apoptosis

    PubMed Central

    YUAN, DONG-DONG; CHI, XIN-JIN; JIN, YI; LI, XI; GE, MIAN; GAO, WAN-LING; GUAN, JIAN-QIANG; ZHANG, AI-LAN; HEI, ZI-QING

    2016-01-01

    Intestinal motility and barriers are often impaired due to intestinal congestion during liver transplantation. Intestinal bacteria and enterogenous endotoxins enter into the blood stream or lymphatic system and translocate to other organs, which can result in postoperative multi-organ dysfunction (MODF) and systemic inflammatory reaction syndrome (SIRS) severely affecting patient survival. However, the mechanisms underlying liver transplantation-induced intestinal injury remain unclear and effective therapies are lacking. Thus, the present study investigated whether these effects were associated with endotoxin-mediated apoptosis. Rat autologous orthotopic liver transplantation (AOLT) models were established to observe dynamic intestinal injuries at different time-points following reperfusion. Changes in the levels of endotoxins and the primary receptor, toll-like receptor 4 (TLR4), as well as its downstream signaling molecule, nuclear factor-κB (NF-κB) were all determined. Finally, immunohistochemistry and terminal deoxynucleotidyl transferase dUTP nick end labeling assays were conducted to detect caspase-3 expression and intestinal cell apoptosis, respectively. AOLT resulted in significant pathological intestinal injury, with the most serious intestine damage apparent four or eight hours following reperfusion. Furthermore, the levels of endotoxins and inflammatory cytokines, such as tumor necrosis factor-α and interleukin-6, peaked during this time period and gradually decreased to the normal level. Notably, TLR4 and downstream NF-κB expression, as well as NF-κB-mediated caspase-3 activation and intestinal cell aapoptosis coincided with the intestinal pathological damage. Thus, the possible mechanism of post-liver transplantation intestinal injury was demonstrated to be associated with NF-κB activation-induced cell apoptosis. PMID:26707779

  12. Factors affecting protein release from alginate-chitosan coacervate microcapsules during production and gastric/intestinal simulation.

    PubMed

    Vandenberg, G W; Drolet, C; Scott, S L; de la Noüe, J

    2001-12-13

    A series of experiments was performed to evaluate the influence of a number of physico-chemical factors on the diffusion of a model protein, bovine serum albumin (BSA), from dried chitosan-coated alginate microcapsules. Diffusion of BSA was quantified during the microcapsule manufacture processes (gelation, washing, rinsing) and during incubation in conditions simulating the pH encountered during the gastric (0.1 N HCl; pH 1.5) and intestinal (200 mM Tris-HCl; pH 7.5) phases of digestion. Factors tested included alginate and chitosan concentration, calcium chloride (CaCl2) concentration in the gelation medium, loading rate, chitosan molecular mass and pH of the gelation medium. Microcapsule size and gelation time were altered in order to determine their effects on protein retention. Alginate and chitosan concentration significantly influenced BSA retention during microcapsule manufacture and acid incubation, as did calcium chloride concentration in the gelation medium (P<0.05). BSA retention during manufacture was not significantly altered by protein loading rate or pH of the encapsulation medium, however, protein retention during acid incubation decreased significantly with increasing protein loading rate and encapsulation medium pH (P<0.05). Microcapsules that were washed with acetone following manufacture demonstrated significantly increased protein retention during acid incubation (P<0.05). In microcapsules that had been acetone-dried to a point whereby their mass was reduced to 10% of that immediately following encapsulation, protein retention was over 80% following 24-h acid incubation vs. only 20% protein retention from non acetone-dried microcapsules. The presence of calcium in the neutral buffer medium significantly reduced BSA diffusion in a concentration-dependent manner (P<0.05).

  13. Electrical Signaling in Motile and Primary Cilia

    PubMed Central

    Kleene, Steven J.; Van Houten, Judith L.

    2014-01-01

    Cilia are highly conserved for their structure and also for their sensory functions. They serve as antennae for extracellular information. Whether the cilia are motile or not, they respond to environmental mechanical and chemical stimuli and send signals to the cell body. The information from extracellular stimuli is commonly converted to electrical signals through the repertoire of ion-conducting channels in the ciliary membrane, which results in changes in concentrations of ions, especially calcium ions, in the cilia. These changes, in turn, affect motility and the ability of the signaling pathways in the cilia and cell body to carry on the signal transduction. We review here the activities of ion channels in cilia in animals from protists to vertebrates. PMID:25892740

  14. Cyclic GMP and Cilia Motility

    PubMed Central

    Wyatt, Todd A.

    2015-01-01

    Motile cilia of the lungs respond to environmental challenges by increasing their ciliary beat frequency in order to enhance mucociliary clearance as a fundamental tenant of innate defense. One important second messenger in transducing the regulable nature of motile cilia is cyclic guanosine 3′,5′-monophosphate (cGMP). In this review, the history of cGMP action is presented and a survey of the existing data addressing cGMP action in ciliary motility is presented. Nitric oxide (NO)-mediated regulation of cGMP in ciliated cells is presented in the context of alcohol-induced cilia function and dysfunction. PMID:26264028

  15. [The motility of the biliary tract studied with 99mTc-Br-IDA in patients with type-2 diabetes mellitus].

    PubMed

    Cangialosi, G; Doria, G; Costa, R; Cirrincione, M; Salerno, V; Allegra, G; Scaffidi, A

    1995-12-01

    Autonomic neuropathy in diabetes mellitus can cause alterations of the motor function of various segments of the gastroenteric apparatus. With hepatocholangio-cholecystiscintigraphy-HIDA we have studied the motility of the biliary system in patients with diabetes mellitus type II. The research has been carried out in 29 patients with diabetic autonomic neuropathy; 12 healthy volunteers have been studied to compare the results obtained. The results showed a delay in the appearance of radionucleotide in the small intestine of diabetic subjects compared to controls with statistical significance. Moreover the diabetic subjects with a serious neuropathic injury showed increased intestinal transit time. These results match those obtained by other authors that have studied the cholecystic emptying in diabetic subjects with other methods. Consequently the biliary system is also affected by the diabetic autonomic neuropathy that can be in its turn the cause of other pathologies such as biliary lithiasis.

  16. Octreotide acetate induces fasting small bowel motility in patients with dumping syndrome.

    PubMed

    Richards, W O; Geer, R; O'Dorisio, T M; Robarts, T; Parish, K L; Rice, D; Woltering, G; Abumrad, N N

    1990-12-01

    The long acting somatostatin analogue octreotide acetate has been effective in the treatment of early dumping syndrome. We hypothesized that this may be related to its effects on inhibiting gastric emptying and delaying intestinal transit. To study the effect of octreotide acetate on intestinal motility in patients we carried out a randomized, double-blinded study using a subcutaneous injection of either octreotide acetate (100 micrograms) or placebo given 20 min prior to ingestion of a high carbohydrate "dumping" meal in six patients with known severe dumping syndrome. Prior to each study a multilumen polyethylene tube was inserted into the efferent limb to study small intestinal contractions using low compliance pneumo-hydraulic water-perfused manometry. Octreotide acetate prevented dumping symptoms in all six patients and induced the appearance of migrating myoelectric complexes (MMC) characteristic of interdigestive motility. After ingestion of the dumping meal the postprandial "fed" motility pattern lasted for 141 +/- 9 min while after octreotide acetate the fed motility lasted for 29 +/- 5 min (P less than 0.03). The vigor of the fed motility pattern as measured by the motility index (MI = loge (sum of amplitudes X No. of contractions + 1] was lower after octreotide acetate than after placebo (15.1 +/- 0.1 vs 13.4 +/- 0.2, P less than 0.03). The induction of fasting MMC motility pattern and reduction in the duration and vigor of fed motility may explain the symptomatic relief these patients obtained with octreotide acetate. It is not known whether the induction of the MMC is a direct effect of octreotide acetate or secondary to the concomitant inhibition of peptide release (neurotensin, insulin, glucagon, pancreatic polypeptide) that has been demonstrated in earlier studies.

  17. Monoglyceride lipase deficiency causes desensitization of intestinal cannabinoid receptor type 1 and increased colonic μ-opioid receptor sensitivity

    PubMed Central

    Taschler, U; Eichmann, T O; Radner, F P W; Grabner, G F; Wolinski, H; Storr, M; Lass, A; Schicho, R; Zimmermann, R

    2015-01-01

    Background and Purpose Monoglyceride lipase (MGL) degrades 2-arachidonoyl glycerol (2-AG), an endogenous agonist of cannabinoid receptors (CB1/2). Because the CB1 receptor is involved in the control of gut function, we investigated the effects of pharmacological inhibition and genetic deletion of MGL on intestinal motility. Furthermore, we determined whether defective 2-AG degradation affects μ-opioid receptor (μ receptor) signalling, a parallel pathway regulating gut motility. Experimental Approach Gut motility was investigated by monitoring Evans Blue transit and colonic bead propulsion in response to MGL inhibition and CB1 receptor or μ receptor stimulation. Ileal contractility was investigated by electrical field stimulation. CB1 receptor expression in ileum and colon was assessed by immunohistochemical analyses. Key Results Pharmacological inhibition of MGL slowed down whole gut transit in a CB1 receptor-dependent manner. Conversely, genetic deletion of MGL did not affect gut transit despite increased 2-AG levels. Notably, MGL deficiency caused complete insensitivity to CB1 receptor agonist-mediated inhibition of whole gut transit and ileal contractility suggesting local desensitization of CB1 receptors. Accordingly, immunohistochemical analyses of myenteric ganglia of MGL-deficient mice revealed that CB1 receptors were trapped in endocytic vesicles. Finally, MGL-deficient mice displayed accelerated colonic propulsion and were hypersensitive to μ receptor agonist-mediated inhibition of colonic motility. This phenotype was reproduced by chronic pharmacological inhibition of MGL. Conclusion and Implications Constantly elevated 2-AG levels induce severe desensitization of intestinal CB1 receptors and increased sensitivity to μ receptor-mediated inhibition of colonic motility. These changes should be considered when cannabinoid-based drugs are used in the therapy of gastrointestinal diseases. PMID:26075589

  18. Effects of erythromycin in chronic idiopathic intestinal pseudo-obstruction.

    PubMed

    Minami, T; Nishibayashi, H; Shinomura, Y; Matsuzawa, Y

    1996-12-01

    The prokinetic effects of erythromycin, a macrolide antibiotic, on the gastrointestinal tract as a motilin receptor agonist and its potential value for the treatment of gastrointestinal motility disorders have recently attracted interest. The effects of erythromycin on the clinical symptoms and gastrointestinal motility of patients with chronic idiopathic pseudo-obstruction have not been investigated extensively. We presented a case of chronic idiopathic intestinal pseudo-obstruction, in a 67-year-old man in whom oral erythromycin (900 mg/day) dramatically improved postprandial abdominal distention, nausea, and vomiting. Other agents with prokinetic effects on intestinal motility, i.e., cisapride, domperidone, metoclopramide, and trimebutine maleate did not have a favorable effect. Gastric emptying, measured by the sulfamethizole method; and intestinal transit, evaluated using radio-opaque markers, were markedly improved by treatment with erythromycin. Our experience suggests that the prokinetic effects of erythromycin may be of therapeutic value in chronic idiopathic intestinal pseudo-obstruction. PMID:9027652

  19. Shape determination in motile cells

    NASA Astrophysics Data System (ADS)

    Mogilner, Alex

    2010-03-01

    Flat, simple shaped, rapidly gliding fish keratocyte cell is the model system of choice to study cell motility. The cell motile appendage, lamellipod, has a characteristic bent-rectangular shape. Recent experiments showed that the lamellipodial geometry is tightly correlated with cell speed and with actin dynamics. These quantitative data combined with computational modeling suggest that a model for robust actin treadmill inside the 'unstretchable membrane bag'. According to this model, a force balance between membrane tension and growing and pushing actin network distributed unevenly along the cell periphery can explain the cell shape and motility. However, when adhesion of the cell to the surface weakens, the actin dynamics become less regular, and myosin-powered contraction starts playing crucial role in stabilizing the cell shape. I will illustrate how the combination of theoretical and experimental approaches helped to unravel the keratocyte motile behavior.

  20. Effects of laxative and nonlaxative hydrophilic polymers on canine small intestinal motor activity.

    PubMed

    Russell, J; Bass, P

    1986-03-01

    Bulk-forming laxatives increase fecal volume and elicit aborally directed colonic motility patterns. Recently, it was demonstrated that test meals of the bulk-laxative fibers (cellulose and bran) elicited organized jejunal motor activity while nonlaxative fiber meals (guar) elicited unorganized jejunal motor activity. However, whether bulk-forming laxatives, as a class of compounds, differentially affect small intestinal motility has not been studied. Therefore, a study was made of the effects of the bulk laxatives psyllium and polycarbophil and the nonlaxative pectin on canine jejunal motor activity. Psyllium and pectin are examples of dietary fiber, while polycarbophil is a synthetic polymer. Pectin and psyllium test meals presented as viscous gels. In contrast, polycarbophil meals presented as a combination of discrete particles plus meal water. After each meal, measurements were made of the jejunal motility index, the time of reappearance of interdigestive burst activity, and overall motility patterns. Pectin and psyllium meals increased in viscosity as meal fiber content increased. As meal content and hence viscosity increased, both the laxative (psyllium) and nonlaxative (pectin) fiber meals elicited increasing jejunal motor activity and delays in the reappearance of the burst interval. For both fiber types, motor activity presented as randomly appearing contractions. In contrast, meals of the laxative polycarbophil elicited no more motor activity than the saline control meal. However, this control-level amount of activity presented as propagated clusters of contractions, ie, the "laxative-induced pattern." Polycarbophil did not delay the reappearance of burst activity.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. Intestinal Malrotation

    MedlinePlus

    ... the intestines don't position themselves normally during fetal development and aren't attached inside properly as a result. The exact reason this occurs is unknown. When a fetus develops in the womb, the intestines start out ...

  2. Link between hypothyroidism and small intestinal bacterial overgrowth.

    PubMed

    Patil, Anant D

    2014-05-01

    Altered gastrointestinal (GI) motility is seen in many pathological conditions. Reduced motility is one of the risk factors for development of a small intestinal bacterial overgrowth (SIBO). Hypothyroidism is associated with altered GI motility. The aim of this article was to study the link between hypothyroidism, altered GI motility and development of SIBO. Published literature was reviewed to study the association of altered GI motility, SIBO and hypothyroidism. Altered GI motility leads to SIBO. SIBO is common in patients with hypothyroidism. Patients with chronic GI symptoms in hypothyroidism should be evaluated for the possibility of SIBO. Both antibiotics and probiotics have been studied and found to be effective in management of SIBO. PMID:24944923

  3. Link between hypothyroidism and small intestinal bacterial overgrowth

    PubMed Central

    Patil, Anant D.

    2014-01-01

    Altered gastrointestinal (GI) motility is seen in many pathological conditions. Reduced motility is one of the risk factors for development of a small intestinal bacterial overgrowth (SIBO). Hypothyroidism is associated with altered GI motility. The aim of this article was to study the link between hypothyroidism, altered GI motility and development of SIBO. Published literature was reviewed to study the association of altered GI motility, SIBO and hypothyroidism. Altered GI motility leads to SIBO. SIBO is common in patients with hypothyroidism. Patients with chronic GI symptoms in hypothyroidism should be evaluated for the possibility of SIBO. Both antibiotics and probiotics have been studied and found to be effective in management of SIBO. PMID:24944923

  4. Intestine Transplant

    MedlinePlus

    ... intestine segment, most intestine transplants involve a whole organ from a deceased donor. In addition, most intestine transplants are performed in ... blood before surgery. I am looking for ... allocation About UNOS Being a living donor Calculator - CPRA Calculator - KDPI Calculator - LAS Calculator - MELD ...

  5. Ribose Accelerates Gut Motility and Suppresses Mouse Body Weight Gaining

    PubMed Central

    Liu, Yan; Li, Tong-Ruei R; Xu, Cong; Xu, Tian

    2016-01-01

    The increasing prevalence of obesity is closely related to excessive energy consumption. Clinical intervention of energy intake is an attractive strategy to fight obesity. However, the current FDA-approved weight-loss drugs all have significant side effects. Here we show that ribose upregulates gut motility and suppresses mice body weight gain. Ribokinase, which is encoded by Rbks gene, is the first enzyme for ribose metabolism in vivo. Rbks mutation resulted in ribose accumulation in the small intestine, which accelerated gut movement. Ribose oral treatment in wild type mice also enhanced bowel motility and rendered mice resistance to high fat diets. The suppressed weight gain was resulted from enhanced ingested food excretion. In addition, the effective dose of ribose didn't cause any known side effects (i.e. diarrhea and hypoglycemia). Overall, our results show that ribose can regulate gut motility and energy homeostasis in mice, and suggest that administration of ribose and its analogs could regulate gastrointestinal motility, providing a novel therapeutic approach for gastrointestinal dysfunction and weight control. PMID:27194947

  6. Oxidized ethyl linoleate induces mucosal hypertrophy of the large intestine and affects cecal fermentation of dietary fiber in rats.

    PubMed

    Hara, H; Miyashita, K; Ito, S; Kasai, T

    1996-04-01

    Oxidized ethyl linoleate (OEL) was prepared by aeration at low temperature. Peroxide value (POV, mEq/kg lipid) of OEL was 1400; the major oxidized compounds were 9-hydroperoxy-cis, trans- and 13-hydroperoxy-trans, cis-octadecadienoate. Rats fed fiber-free or sugar-beet fiber (SBF, 100g/kg diet) diets were divided into three groups for each diet, and administered OEL (high OEL group), OEL diluted with ethyl linoleate (low OEL group, POV 700) and nonoxidized ethyl linoleate (EL group) through gastric tubes each day at 1400-1600 h (2.5 g/kg body wt) for 16 d. The relative wet weight, and DNA and protein contents of the cecal mucosa were higher in the high OEL groups than in the low OEL and EL groups in rats fed the fiber-free diet and in rats fed the SBF diet except for mucosal protein content. Spermidine concentration in cecal mucosa of rats fed the fiber-free diet was greater in the high OEL group than in the EL group. These results suggest that metabolism related to mucosal proliferation of the cecum was affected by the high dose of OEL. The total short-chain fatty acid (SCFA) concentration in the cecal contents of SBF-fed rats was 100% higher than the concentration in rats fed the fiber-free diet in the EL group, but the administration of low dose and high dose OEL lowered the SCFA concentration in fiber-fed rats to that of rats fed the fiber-free diet. Butyric acid concentration was markedly lowered by ingestion of OEL in a dose-dependent manner in rats fed the SBF diet. In contrast, the isobutyric acid concentration was higher in the OEL-treated groups than in the EL groups. We conclude that a low dose of OEL depresses cecal fermentation of dietary fiber with changes in SCFA composition, and that a high dose of OEL induces mucosal hypertrophy in the cecum. These data show that dietary oxidized lipids affect cecal metabolism and may be associated with colon cancer.

  7. In vivo imaging and genetic analysis link bacterial motility and symbiosis in the zebrafish gut

    PubMed Central

    Rawls, John F.; Mahowald, Michael A.; Goodman, Andrew L.; Trent, Chad M.; Gordon, Jeffrey I.

    2007-01-01

    Complex microbial communities reside within the intestines of humans and other vertebrates. Remarkably little is known about how these microbial consortia are established in various locations within the gut, how members of these consortia behave within their dynamic ecosystems, or what microbial factors mediate mutually beneficial host–microbial interactions. Using a gnotobiotic zebrafish–Pseudomonas aeruginosa model, we show that the transparency of this vertebrate species, coupled with methods for raising these animals under germ-free conditions can be used to monitor microbial movement and localization within the intestine in vivo and in real time. Germ-free zebrafish colonized with isogenic P. aeruginosa strains containing deletions of genes related to motility and pathogenesis revealed that loss of flagellar function results in attenuation of evolutionarily conserved host innate immune responses but not conserved nutrient responses. These results demonstrate the utility of gnotobiotic zebrafish in defining the behavior and localization of bacteria within the living vertebrate gut, identifying bacterial genes that affect these processes, and assessing the impact of these genes on host–microbial interactions. PMID:17456593

  8. Activation of sperm motility in striped bass via a cAMP-independent pathway.

    PubMed

    He, Shuyang; Jenkins-Keeran, Karen; Woods, L Curry

    2004-05-01

    The objective of the present study was to identify the effect of osmolality, ions (K+, H+, Ca2+, Mg2+) and cAMP on the initiation of sperm motility in striped bass (Morone saxatilis). Striped bass spermatozoa remained motile in solutions isotonic to seminal plasma (350 mOsm/kg) until osmolality reached 600 mOsm/kg. K+ (0-100 mM) had no effect ( p>0.05 ) on sperm motility, and sperm displayed a high percentage of motility over a wide range of pH (6.0-8.5). Sperm motility could be initiated in Ca2+-free solutions. In contrast, sperm motility was inhibited (P<0.01) by solutions containing > or =10 mM Ca2+, and sperm could not be reactivated by a Ca2+-free solution. This Ca2+ inhibition was not affected by verapamil, a Ca2+ channel blocker. However, if sperm motility was first initiated in a Ca2+-free solution, the addition of Ca2+ solutions, up to 80 mM, failed to inhibit sperm motility, suggesting that Ca2+ inhibited the initiation of motility, but had no control of motile spermatozoa. Mg2+ solutions had similar inhibitory effects on sperm motility as Ca2+ solutions. Therefore, initiation of motility in striped bass sperm may be related to voltage-gated channels across the cell's plasma membrane. Membrane permeable cAMP did not initiate motility of quiescent, intact striped bass spermatozoa, and motility of demembranated sperm could be activated in the absence of cAMP.

  9. Effect of premedication with diazepam, morphine or nalbuphine on gastrointestinal motility after surgery.

    PubMed

    Shah, M; Rosen, M; Vickers, M D

    1984-11-01

    Premedication with nalbuphine and morphine delayed gastric emptying in the period after operation, but oral diazepam did not. All three drugs delayed co-ordinated intestinal motility, although nalbuphine did so for less than half as long as morphine. This property of nalbuphine, if confirmed, could make it a valuable analgesic drug in the period after operation. PMID:6487444

  10. Effect of genetic SSTR4 ablation on inflammatory peptide and receptor expression in the non-inflamed and inflamed murine intestine.

    PubMed

    Van Op den Bosch, Joeri; Torfs, Pascal; De Winter, Benedicte Y; De Man, Joris G; Pelckmans, Paul A; Van Marck, Eric; Grundy, David; Van Nassauw, Luc; Timmermans, Jean-Pierre

    2009-09-01

    The recently suggested pivotal role of somatostatin (SOM) receptor 4 (SSTR4) in inflammation and nociception in several non-intestinal organs and in gastrointestinal (GI) physiology, necessitates exploration of the role of SSTR4 in GI pathophysiology. Therefore, the role of SSTR4 in GI activity was explored by investigating the effects of SSTR4 deficiency on intestinal motility, smooth muscle contractility and on the expression of SSTRs and neuropeptides in the healthy and Schistosoma mansoni-infected murine small intestine. Functional experiments revealed no differences in intestinal motility or smooth muscle cell contractility between wild-type and SSTR4 knockout (SSTR4(-/-)) mice in physiological conditions. As revealed by multiple immunofluorescent labellings, RT-PCR and quantitative real time RT-PCR (qPCR), genetic deficiency of SSTR4 considerably altered the expression of SOM and SSTRs in non-inflamed and inflamed conditions, affecting both extrinsic and intrinsic components of the intestinal innervation, along with SSTR expression in several non-neuronal cell types. Moreover, substance P and calcitonin gene-related peptide expression were significantly elevated in SSTR4(-/-) mice, confirming the modulatory role of SSTR4 on intestinal pro-inflammatory neuropeptide expression. These data suggest that SSTR4 plays a previously unexpected modulatory role in the regulation of intestinal SSTR expression. Moreover, in addition to the recently described inhibitory effects of SSTR4 on the neuronal release of pro-inflammatory peptides, SSTR4 appears also to be involved in the neuronal expression of both pro- and anti-inflammatory peptides in the murine small intestine.

  11. Proteomic changes of the porcine small intestine in response to chronic heat stress.

    PubMed

    Cui, Yanjun; Gu, Xianhong

    2015-12-01

    Acute heat stress (HS) negatively affects intestinal integrity and barrier function. In contrast, chronic mild HS poses a distinct challenge to animals. Therefore, this study integrates biochemical, histological and proteomic approaches to investigate the effects of chronic HS on the intestine in finishing pigs. Castrated male crossbreeds (79.00 ± 1.50 kg BW) were subjected to either thermal neutral (TN, 21 °C; 55% ± 5% humidity; n=8) or HS conditions (30 °C; 55% ± 5% humidity; n=8) for 3 weeks. The pigs were sacrificed after 3 weeks of high environmental exposure and the plasma hormones, the intestinal morphology, integrity, and protein profiles of the jejunum mucosa were determined. Chronic HS reduced the free triiodothyronine (FT3) and GH levels. HS damaged intestinal morphology, increased plasma d-lactate concentrations and decreased alkaline phosphatase activity of intestinal mucosa. Proteome analysis of the jejunum mucosa was conducted by 2D gel electrophoresis and mass spectrometry. Fifty-three intestinal proteins were found to be differentially abundant, 18 of which were related to cell structure and motility, and their changes in abundance could comprise intestinal integrity and function. The down-regulation of proteins involved in tricarboxylic acid cycle (TCA cycle), electron transport chain (ETC), and oxidative phosphorylation suggested that chronic HS impaired energy metabolism and thus induced oxidative stress. Moreover, the changes of ten proteins in abundance related to stress response and defense indicated pigs mediated long-term heat exposure and counteracted its negative effects of heat exposure. These findings have important implications for understanding the effect of chronic HS on intestines.

  12. Proteomic changes of the porcine small intestine in response to chronic heat stress

    PubMed Central

    Cui, Yanjun; Gu, Xianhong

    2015-01-01

    Acute heat stress (HS) negatively affects intestinal integrity and barrier function. In contrast, chronic mild HS poses a distinct challenge to animals. Therefore, this study integrates biochemical, histological and proteomic approaches to investigate the effects of chronic HS on the intestine in finishing pigs. Castrated male crossbreeds (79.00±1.50 kg BW) were subjected to either thermal neutral (TN, 21 °C; 55%±5% humidity; n=8) or HS conditions (30 °C; 55%±5% humidity; n=8) for 3 weeks. The pigs were sacrificed after 3 weeks of high environmental exposure and the plasma hormones, the intestinal morphology, integrity, and protein profiles of the jejunum mucosa were determined. Chronic HS reduced the free triiodothyronine (FT3) and GH levels. HS damaged intestinal morphology, increased plasma d-lactate concentrations and decreased alkaline phosphatase activity of intestinal mucosa. Proteome analysis of the jejunum mucosa was conducted by 2D gel electrophoresis and mass spectrometry. Fifty-three intestinal proteins were found to be differentially abundant, 18 of which were related to cell structure and motility, and their changes in abundance could comprise intestinal integrity and function. The down-regulation of proteins involved in tricarboxylic acid cycle (TCA cycle), electron transport chain (ETC), and oxidative phosphorylation suggested that chronic HS impaired energy metabolism and thus induced oxidative stress. Moreover, the changes of ten proteins in abundance related to stress response and defense indicated pigs mediated long-term heat exposure and counteracted its negative effects of heat exposure. These findings have important implications for understanding the effect of chronic HS on intestines. PMID:26416815

  13. Appropriate chicken sample size for identifying the composition of broiler intestinal microbiota affected by dietary antibiotics, using the polymerase chain reaction-denaturing gradient gel electrophoresis technique.

    PubMed

    Zhou, H; Gong, J; Brisbin, J T; Yu, H; Sanei, B; Sabour, P; Sharif, S

    2007-12-01

    The bacterial microbiota in the broiler gastrointestinal tract are crucial for chicken health and growth. Their composition can vary among individual birds. To evaluate the composition of chicken microbiota in response to environmental disruption accurately, 4 different pools made up of 2, 5, 10, and 15 individuals were used to determine how many individuals in each pool were required to assess the degree of variation when using the PCR-denaturing gradient gel electrophoresis (DGGE) profiling technique. The correlation coefficients among 3 replicates within each pool group indicated that the optimal sample size for comparing PCR-DGGE bacterial profiles and downstream applications (such as identifying treatment effects) was 5 birds per pool for cecal microbiota. Subsequently, digesta from 5 birds was pooled to investigate the effects on the microbiota composition of the 2 most commonly used dietary antibiotics (virginiamycin and bacitracin methylene disalicylate) at 2 different doses by using PCR-DGGE, DNA sequencing, and quantitative PCR techniques. Thirteen DGGE DNA bands were identified, representing bacterial groups that had been affected by the antibiotics. Nine of them were validated. The effect of dietary antibiotics on the microbiota composition appeared to be dose and age dependent. These findings provide a working model for elucidating the mechanisms of antibiotic effects on the chicken intestinal microbiota and for developing alternatives to dietary antibiotics. PMID:18029800

  14. Gastrointestinal motility in space motion sickness

    NASA Technical Reports Server (NTRS)

    Thornton, William E.; Linder, Barry J.; Moore, Thomas P.; Pool, Sam L.

    1987-01-01

    Gastrointestinal symptoms in space motion sickness (SMS) are significantly different from those in ordinary motion sickness (MS). Recording and tabulation of sounds was the only technique that could be used as a measure of motility during spaceflight operations. There were 17 subjects, six unaffected by SMS, who made ambulatory recordings preflight and inflight. With one exception, all those affected had sharply reduced sounds, while those unaffected had increases or moderate reductions. The mechanism of vomiting in SMS appears to be secondary to this ileus, in contrast to vomiting in ordinary MS, where the emesis center is thought to be directly triggered by the vestibular system.

  15. Shikonin Inhibits Intestinal Calcium-Activated Chloride Channels and Prevents Rotaviral Diarrhea.

    PubMed

    Jiang, Yu; Yu, Bo; Yang, Hong; Ma, Tonghui

    2016-01-01

    Secretory diarrhea remains a global health burden and causes major mortality in children. There have been some focuses on antidiarrheal therapies that may reduce fluid losses and intestinal motility in diarrheal diseases. In the present study, we identified shikonin as an inhibitor of TMEM16A chloride channel activity using cell-based fluorescent-quenching assay. The IC50 value of shikonin was 6.5 μM. Short-circuit current measurements demonstrated that shikonin inhibited Eact-induced Cl(-) current in a dose-dependent manner, with IC50 value of 1.5 μM. Short-circuit current measurement showed that shikonin exhibited inhibitory effect against CCh-induced Cl(-) currents in mouse colonic epithelia but did not affect cytoplasmic Ca(2+) concentration as well as the other major enterocyte chloride channel conductance regulator. Characterization study found that shikonin inhibited basolateral K(+) channel activity without affecting Na(+)/K(+)-ATPase activities. In vivo studies revealed that shikonin significantly delayed intestinal motility in mice and reduced stool water content in a neonatal mice model of rotaviral diarrhea without affecting the viral infection process in vivo. Taken together, the results suggested that shikonin inhibited enterocyte calcium-activated chloride channels, the inhibitory effect was partially through inhbition of basolateral K(+) channel activity, and shikonin could be a lead compound in the treatment of rotaviral secretory diarrhea.

  16. Shikonin Inhibits Intestinal Calcium-Activated Chloride Channels and Prevents Rotaviral Diarrhea

    PubMed Central

    Jiang, Yu; Yu, Bo; Yang, Hong; Ma, Tonghui

    2016-01-01

    Secretory diarrhea remains a global health burden and causes major mortality in children. There have been some focuses on antidiarrheal therapies that may reduce fluid losses and intestinal motility in diarrheal diseases. In the present study, we identified shikonin as an inhibitor of TMEM16A chloride channel activity using cell-based fluorescent-quenching assay. The IC50 value of shikonin was 6.5 μM. Short-circuit current measurements demonstrated that shikonin inhibited Eact-induced Cl- current in a dose-dependent manner, with IC50 value of 1.5 μM. Short-circuit current measurement showed that shikonin exhibited inhibitory effect against CCh-induced Cl- currents in mouse colonic epithelia but did not affect cytoplasmic Ca2+ concentration as well as the other major enterocyte chloride channel conductance regulator. Characterization study found that shikonin inhibited basolateral K+ channel activity without affecting Na+/K+-ATPase activities. In vivo studies revealed that shikonin significantly delayed intestinal motility in mice and reduced stool water content in a neonatal mice model of rotaviral diarrhea without affecting the viral infection process in vivo. Taken together, the results suggested that shikonin inhibited enterocyte calcium-activated chloride channels, the inhibitory effect was partially through inhbition of basolateral K+ channel activity, and shikonin could be a lead compound in the treatment of rotaviral secretory diarrhea. PMID:27601995

  17. Shikonin Inhibits Intestinal Calcium-Activated Chloride Channels and Prevents Rotaviral Diarrhea.

    PubMed

    Jiang, Yu; Yu, Bo; Yang, Hong; Ma, Tonghui

    2016-01-01

    Secretory diarrhea remains a global health burden and causes major mortality in children. There have been some focuses on antidiarrheal therapies that may reduce fluid losses and intestinal motility in diarrheal diseases. In the present study, we identified shikonin as an inhibitor of TMEM16A chloride channel activity using cell-based fluorescent-quenching assay. The IC50 value of shikonin was 6.5 μM. Short-circuit current measurements demonstrated that shikonin inhibited Eact-induced Cl(-) current in a dose-dependent manner, with IC50 value of 1.5 μM. Short-circuit current measurement showed that shikonin exhibited inhibitory effect against CCh-induced Cl(-) currents in mouse colonic epithelia but did not affect cytoplasmic Ca(2+) concentration as well as the other major enterocyte chloride channel conductance regulator. Characterization study found that shikonin inhibited basolateral K(+) channel activity without affecting Na(+)/K(+)-ATPase activities. In vivo studies revealed that shikonin significantly delayed intestinal motility in mice and reduced stool water content in a neonatal mice model of rotaviral diarrhea without affecting the viral infection process in vivo. Taken together, the results suggested that shikonin inhibited enterocyte calcium-activated chloride channels, the inhibitory effect was partially through inhbition of basolateral K(+) channel activity, and shikonin could be a lead compound in the treatment of rotaviral secretory diarrhea. PMID:27601995

  18. Shikonin Inhibits Intestinal Calcium-Activated Chloride Channels and Prevents Rotaviral Diarrhea

    PubMed Central

    Jiang, Yu; Yu, Bo; Yang, Hong; Ma, Tonghui

    2016-01-01

    Secretory diarrhea remains a global health burden and causes major mortality in children. There have been some focuses on antidiarrheal therapies that may reduce fluid losses and intestinal motility in diarrheal diseases. In the present study, we identified shikonin as an inhibitor of TMEM16A chloride channel activity using cell-based fluorescent-quenching assay. The IC50 value of shikonin was 6.5 μM. Short-circuit current measurements demonstrated that shikonin inhibited Eact-induced Cl- current in a dose-dependent manner, with IC50 value of 1.5 μM. Short-circuit current measurement showed that shikonin exhibited inhibitory effect against CCh-induced Cl- currents in mouse colonic epithelia but did not affect cytoplasmic Ca2+ concentration as well as the other major enterocyte chloride channel conductance regulator. Characterization study found that shikonin inhibited basolateral K+ channel activity without affecting Na+/K+-ATPase activities. In vivo studies revealed that shikonin significantly delayed intestinal motility in mice and reduced stool water content in a neonatal mice model of rotaviral diarrhea without affecting the viral infection process in vivo. Taken together, the results suggested that shikonin inhibited enterocyte calcium-activated chloride channels, the inhibitory effect was partially through inhbition of basolateral K+ channel activity, and shikonin could be a lead compound in the treatment of rotaviral secretory diarrhea.

  19. Dietary strawberry seed oil affects metabolite formation in the distal intestine and ameliorates lipid metabolism in rats fed an obesogenic diet

    PubMed Central

    Jurgoński, Adam; Fotschki, Bartosz; Juśkiewicz, Jerzy

    2015-01-01

    Objective To answer the question whether dietary strawberry seed oil rich in α-linolenic acid and linoleic acid (29.3 and 47.2% of total fatty acids, respectively) can beneficially affect disorders induced by the consumption of an obesogenic diet. Design Thirty-two male Wistar rats were randomly assigned to four groups of eight animals each and fed with a basal or obesogenic (high in fat and low in fiber) diet that contained either strawberry seed oil or an edible rapeseed oil. A two-way analysis of variance was then applied to assess the effects of diet and oil and the interaction between them. Results After 8 weeks of feeding, the obesogenic diet increased the body weight and the liver mass and fat content, whereas decreased the cecal acetate and butyrate concentration. This diet also altered the plasma lipid profile and decreased the liver sterol regulatory element-binding protein 1c (SREBP-1c) content. However, the lowest liver SREBP-1c content was observed in rats fed an obesogenic diet containing strawberry seed oil. Moreover, dietary strawberry seed oil decreased the cecal short-chain fatty acid concentrations (acetate, propionate, and butyrate) regardless of the diet type, whereas the cecal β-glucuronidase activity was considerably increased only in rats fed an obesogenic diet containing strawberry seed oil. Dietary strawberry seed oil also lowered the liver fat content, the plasma triglyceride level and the atherogenic index of plasma. Conclusions Strawberry seed oil has a potent lipid-lowering activity but can unfavorably affect microbial metabolism in the distal intestine. The observed effects are partly due to the synergistic action of the oil and the obesogenic diet. PMID:25636326

  20. Effects of environment factors on initiation of sperm motility in sea cucumber Apostichopus japonicus (Selenka)

    NASA Astrophysics Data System (ADS)

    Yu, Li; Shao, Mingyu; Bao, Zhenmin; Hu, Jingjie; Zhang, Zhifeng

    2011-06-01

    Sperm of sea cucumber Apostichopus japonicus (Selenka) were quiescent in electrolyte NaCl solution and artificial seawater (ASW) and nonelectrolyte glucose and mannitol solutions when the osmolality was less than 200 mOsm kg-1. The sperm started to be motile as a result of increased osmolality, indicating an osmolality-dependent initiation of sperm motility in sea cucumber. After a brief incubation in hypotonic NaCl and glucose solutions with osmolalities of 200 and 400 mOsm kg-1, sperm lost partial motile ability. Sperm became immobilized when pH was 6.0 in NaCl, glucose and mannitol solutions, suggesting that an H+ release is involved in sperm activation. The decreased pH had no effect on the percentage of motile sperm in ASW, whereas it delayed the time period to reach the maximum motility (motilitymax). Extracellular Ca2+ in electrolyte solutions was not essential for motility stimulation but shortened the time of reaching motilitymax. When Ca2+ was mixed in nonelectrolyte solutions the sperm motility was completely suppressed. The K+ channel blocker, quinine, suppressed the sperm motility in electrolyte solution, showing a possible involvement of K+ transport in the process. High K+ concentration did not affect the sperm motility in NaCl solution, but decreased it in ASW and almost entirely suppressed it in nonelectrolyte solutions. The different effects of pH and K+ in ASW and NaCl solution indicate that external ions may also regulate sperm motility.

  1. [Mechanism of bacterial gliding motility].

    PubMed

    Nakane, Daisuke

    2015-01-01

    Bacteria have various way to move over solid surfaces, such as glass, agar, and host cell. These movements involve surface appendages including flagella, type IV pili and other "mysterious" nano-machineries. Gliding motility was a term used various surface movements by several mechanisms that have not been well understood in past few decades. However, development of visualization techniques allowed us to make much progress on their dynamics of machineries. It also provided us better understanding how bacteria move over surfaces and why bacteria move in natural environments. In this review, I will introduce recent studies on the gliding motility of Flavobacteium and Mycoplasma based on the detail observation of single cell and its motility machinery with micro-nano scales. PMID:26632217

  2. Apramycin treatment affects selection and spread of a multidrug-resistant Escherichia coli strain able to colonize the human gut in the intestinal microbiota of pigs.

    PubMed

    Herrero-Fresno, Ana; Zachariasen, Camilla; Hansen, Monica Hegstad; Nielsen, Alexander; Hendriksen, Rene S; Nielsen, Søren Saxmose; Olsen, John Elmerdahl

    2016-01-07

    The effect of apramycin treatment on transfer and selection of an Escherichia coli strain (E. coli 912) in the intestine of pigs was analyzed through an in vivo experiment. The strain was sequenced and assigned to the sequence type ST101 and serotype O11. It carried resistance genes to apramycin/gentamicin, sulphonamide, tetracycline, hygromycin B, β-lactams and streptomycin [aac(3)-IV, sul2, tet(X), aph(4), bla TEM-1 and strA/B], with all but tet(X) located on the same conjugative plasmid. Nineteen pigs were randomly allocated into two inoculation groups, one treated with apramycin (pen 2) and one non-treated (pen 3), along with a non-inoculated control group (pen 1). Two pigs of pen 2 and 3 were inoculated intragastrically with a rifampicin resistant variant of the strain. Apramycin treatment in pen 2 was initiated immediately after inoculation. Strain colonization was assessed in the feces from all pigs. E. coli 912 was shown to spread to non-inoculated pigs in both groups. The selective effect did not persist beyond 3 days post-treatment, and the strain was not detected from this time point in pen 2. We demonstrated that E. coli 912 was able to spread between pigs in the same pen irrespective of treatment, and apramycin treatment resulted in significantly higher counts compared to the non-treated group. This represents the first demonstration of how antimicrobial treatment affects spread of resistant bacteria in pig production. The use of apramycin may lead to enhanced spread of gentamicin-resistant E. coli. Since gentamicin is a first-choice drug for human bacteremia, this is of concern.

  3. Application of the 51Cr-EDTA urinary recovery test for assessment of intestinal permeability in the horse.

    PubMed

    Escala, J; Gatherer, M E; Voûte, L; Love, S

    2006-04-01

    Altered intestinal permeability is implicated in the pathogenesis of diverse equine medical conditions including alimentary laminitis and protein-losing enteropathies associated with parasitic infection. The aims of this study were to assess the feasibility of applying the 51Cr-EDTA absorption test for the assessment of intestinal permeability in the horse, and to apply this test in horses with experimentally induced alterations in gastrointestinal function. Four healthy ponies were administered 36 MBq of 51Cr-EDTA via naso-gastric tube, and urine samples were collected into polythene bags strapped to the pony's abdomen. Total urine voided every 6 h was collected during each test, and 1 ml samples were taken for measurement of gamma-radiation. Urinary recovery of 51Cr-EDTA was measured following intravenous atropine sulphate or bethanecol, and following 22 and 46 days of administration of 250,000 third-stage cyathostome larvae. There was no significant difference in urinary 51Cr-EDTA recovery following the control treatment, and following atropine or bethanecol administration, but significant increases were detected in the animals with experimental cyathostome infection consistent with increased permeability of the intestinal membrane. Motility modifying agents (bethanecol and atropine) did not affect absorption of 51Cr-EDTA, suggesting that subtle changes in motility might not affect the ability of this test to detect altered intestinal permeability. The finding of increased urinary recovery of 51Cr-EDTA in ponies with cyathostome infection suggests that 51Cr-EDTA may be a useful marker for assessment of intestinal permeability in the horse.

  4. Swarming motility by Photorhabdus temperata is influenced by environmental conditions and uses the same flagella as that used in swimming motility.

    PubMed

    Michaels, Brandye; Tisa, Louis S

    2011-03-01

    Photorhabdus temperata, an insect pathogen and nematode symbiont, is motile in liquid medium by swimming. We found that P. temperata was capable of surface movement, termed swarming behavior. Several lines of evidence indicate that P. temperata use the same flagella for both swimming and swarming motility. Both motility types required additional NaCl or KCl in the medium and had peritrichous flagella, which were composed of the same flagellin as detected by immunoblotting experiments. Mutants defective in flagellar structural proteins were nonmotile for both motility types. Unlike swimming, we observed swarming behavior to be a social form of movement in which the cells coordinately formed intricate channels covering a surface. The constituents of the swarm media affected motility. Swarming was optimal on low agar concentrations; as agar concentrations increased, swarm ring diameters decreased.

  5. Management of irritable bowel syndrome: novel approaches to the pharmacology of gut motility.

    PubMed

    Scarpignato, C; Pelosini, I

    1999-03-01

    Although it is unclear to what extent irritable bowel syndrome (IBS) symptoms represent a normal perception of abnormal function or an abnormal perception of normal function, many believe that IBS constitutes the clinical expression of an underlying motility disorder, affecting primarily the mid- and lower gut. Indeed, transit and contractile abnormalities have been demonstrated with sophisticated techniques in a subset of patients with IBS. As a consequence, drugs affecting gastrointestinal (GI) motility have been widely employed with the aim of correcting the major IBS manifestations, ie, pain and altered bowel function. Unfortunately, no single drug has proven to be effective in treating IBS symptom complex. In addition, the use of some medications has often been associated with unpleasant side effects. Therefore, the search for a truly effective and safe drug to control motility disturbances in IBS continues. Several classes of drugs look promising and are under evaluation. Among the motor-inhibiting drugs, gut selective muscarinic antagonists (such as zamifenacin and darifenacin), neurokinin2 antagonists (such as MEN-10627 and MEN-11420), beta3-adrenoreceptor agonists (eg, SR-58611A) and GI-selective calcium channel blockers (eg, pinaverium bromide and octylonium) are able to decrease painful contractile activity in the gut (antispasmodic effect), without significantly affecting other body functions. Novel mechanisms to stimulate GI motility and transit include blockade of cholecystokinin (CCK)A receptors and stimulation of motilin receptors. Loxiglumide (and its dextroisomer, dexloxiglumide) is the only CCKA receptor antagonist that is being evaluated clinically. This drug accelerates gastric emptying and colonic transit, thereby increasing the number of bowel movements in patients with chronic constipation. It is also able to reduce visceral perception. Erythromycin and related 14-member macrolide compounds inhibit the binding of motilin to its receptors on

  6. Cell motility and antibiotic tolerance of bacterial swarms

    NASA Astrophysics Data System (ADS)

    Zuo, Wenlong

    Many bacteria species can move across moist surfaces in a coordinated manner known as swarming. It is reported that swarm cells show higher tolerance to a wide variety of antibiotics than planktonic cells. We used the model bacterium E. coli to study how motility affects the antibiotic tolerance of swarm cells. Our results provide new insights for the control of pathogenic invasion via regulating cell motility. Mailing address: Room 306 Science Centre North Block, The Chinese University of Hong Kong, Shatin, N.T. Hong Kong SAR. Phone: +852-3943-6354. Fax: +852-2603-5204. E-mail: zwlong@live.com.

  7. Intestinal Parasitoses.

    ERIC Educational Resources Information Center

    Lagardere, Bernard; Dumburgier, Elisabeth

    1994-01-01

    Intestinal parasites have become a serious public health problem in tropical countries because of the climate and the difficulty of achieving efficient hygiene. The objectives of this journal issue are to increase awareness of the individual and collective repercussions of intestinal parasites, describe the current conditions of contamination and…

  8. Effect of 655-nm diode laser on dog sperm motility.

    PubMed

    Corral-Baqués, M I; Rigau, T; Rivera, M; Rodríguez, J E; Rigau, J

    2005-01-01

    Sperm motility depends on energy consumption. Low-level laser irradiation increases adenosin triphosphate (ATP) production and energy supply to the cell. The aim of this study is to analyse whether the irradiation affects the parameters that characterise dog sperm motility. Fresh dog sperm samples were divided into four groups and irradiated with a 655-nm continuous-wave diode laser with varying doses: 0 (control), 4, 6 and 10 J/cm(2). At 0, 15 and 45 min following irradiation, pictures were taken of all the groups in order to study motility with computer-aided sperm analysis (CASA). Functional tests were also performed. Average path velocity (VAP), linear coefficient (Lin) and beat cross frequency (BCF) were statistically and significantly different when compared to the control. The functional tests also showed a significant difference. At these parameters, the 655-nm continuous-wave diode laser improves the speed and linear coefficient of the sperm.

  9. Cinnamon polyphenols regulate multiple metabolic pathways involved in intestinal lipid metabolism of primary small intestinal enterocytes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increasing evidence suggests that dietary factors may affect the expression of multiple genes and signaling pathways including those that regulate intestinal lipoprotein metabolism. The small intestine is actively involved in the regulation of dietary lipid absorption, intracellular transport and me...

  10. Effect of preoperative suggestion on postoperative gastrointestinal motility.

    PubMed Central

    Disbrow, E A; Bennett, H L; Owings, J T

    1993-01-01

    Autonomic behavior is subject to direct suggestion. We found that patients undergoing major operations benefit more from instruction than from information and reassurance. We compared the return of intestinal function after intra-abdominal operations in 2 groups of patients: the suggestion group received specific instructions for the early return of gastrointestinal motility, and the control group received an equal-length interview offering reassurance and nonspecific instructions. The suggestion group had a significantly shorter average time to the return of intestinal motility, 2.6 versus 4.1 days. Time to discharge was 6.5 versus 8.1 days. Covariates including duration of operation, amount of intraoperative bowel manipulation, and amount of postoperative narcotics were also examined using the statistical model analysis of covariance. An average savings of $1,200 per patient resulted from this simple 5-minute intervention. In summary, the use of specific physiologically active suggestions given preoperatively in a beleivable manner can reduce the morbidity associated with an intra-abdominal operation by reducing the duration of ileus. PMID:8342264

  11. Nutrigenomic profiling of transcriptional processes affected in liver and distal intestine in response to a soybean meal-induced nutritional stress in Atlantic salmon (Salmo salar).

    PubMed

    De Santis, Christian; Bartie, Kerry L; Olsen, Rolf E; Taggart, John B; Tocher, Douglas R

    2015-09-01

    The aim of the present study was to generate an experimental model to characterize the nutrigenomic profile of a plant-derived nutritional stress. Atlantic salmon (Salmo salar) was used as the model species. The nutritional stress was induced by inclusion of dietary defatted soybean meal (SBM), as this ingredient had been previously demonstrated to induce enteropathy in the distal intestine and reduce growth in salmon. Triplicate groups of Atlantic salmon were fed concentrations of 0, 100, 200 and 300 g kg(-1) SBM for 12 weeks and reduced growth performance was used as the indicator of nutritional stress. The transcriptome was analyzed in two tissues, liver and distal intestine, with the hypothesis being that the liver transcriptome would be characterized by gene expression responses related to overall growth and health performance, whereas intestinal gene expression would be dominated by specific responses to SBM. A set of 133 genes was differentially expressed in liver including 44 genes in common with the intestinal response. The liver-specific response included up-regulation of genes involved in protein digestion, energy metabolism and immune functions, whereas genes in other metabolic pathways were generally anabolic and down-regulated. These responses may be more related to general nutritional stress than to SBM per se. The transcriptomic profile in the distal intestine was consistent with the enteritis response as described previously. This study provides a comprehensive report on the profiles of liver and distal intestine transcriptomes, specifically highlighting the role of the liver in fish undergoing SBM-induced nutritional stress.

  12. Different computer-assisted sperm analysis (CASA) systems highly influence sperm motility parameters.

    PubMed

    Boryshpolets, S; Kowalski, R K; Dietrich, G J; Dzyuba, B; Ciereszko, A

    2013-10-15

    In this study, we examined different computer-assisted sperm analysis (CASA) systems (CRISMAS, Hobson Sperm Tracker, and Image J CASA) on the exact same video recordings to evaluate the differences in sperm motility parameters related to the specific CASA used. To cover a wide range of sperm motility parameters, we chose 12-second video recordings at 25 and 50 Hz frame rates after sperm motility activation using three taxonomically distinct fish species (sterlet: Acipenser ruthenus L.; common carp: Cyprinus carpio L.; and rainbow trout: Oncorhynchus mykiss Walbaum) that are characterized by essential differences in sperm behavior during motility. Systematically higher values of velocity and beat cross frequency (BCF) were observed in video recordings obtained at 50 Hz frame frequency compared with 25 Hz for all three systems. Motility parameters were affected by the CASA and species used for analyses. Image J and CRISMAS calculated higher curvilinear velocity (VCL) values for rainbow trout and common carp at 25 Hz frequency compared with the Hobson Sperm Tracker, whereas at 50 Hz, a significant difference was observed only for rainbow trout sperm recordings. No significant difference was observed between the CASA systems for sterlet sperm motility at 25 and 50 Hz. Additional analysis of 1-second segments taken at three time points (1, 6, and 12 seconds of the recording) revealed a dramatic decrease in common carp and rainbow trout sperm speed. The motility parameters of sterlet spermatozoa did not change significantly during the 12-second motility period and should be considered as a suitable model for longer motility analyses. Our results indicated that the CASA used can affect motility results even when the same motility recordings are used. These results could be critically altered by the recording quality, time of analysis, and frame rate of camera, and could result in erroneous conclusions.

  13. Intestinal steroidogenesis.

    PubMed

    Bouguen, Guillaume; Dubuquoy, Laurent; Desreumaux, Pierre; Brunner, Thomas; Bertin, Benjamin

    2015-11-01

    Steroids are fundamental hormones that control a wide variety of physiological processes such as metabolism, immune functions, and sexual characteristics. Historically, steroid synthesis was considered a function restricted to the adrenals and the gonads. In the past 20 years, a significant number of studies have demonstrated that steroids could also be synthesized or metabolized by other organs. According to these studies, the intestine appears to be a major source of de novo produced glucocorticoids as well as a tissue capable of producing and metabolizing sex steroids. This finding is based on the detection of steroidogenic enzyme expression as well as the presence of bioactive steroids in both the rodent and human gut. Within the intestinal mucosa, the intestinal epithelial cell layer is one of the main cellular sources of steroids. Glucocorticoid synthesis regulation in the intestinal epithelial cells is unique in that it does not involve the classical positive regulator steroidogenic factor-1 (SF-1) but a closely related homolog, namely the liver receptor homolog-1 (LRH-1). This local production of immunoregulatory glucocorticoids contributes to intestinal homeostasis and has been linked to pathophysiology of inflammatory bowel diseases. Intestinal epithelial cells also possess the ability to metabolize sex steroids, notably estrogen; this mechanism may impact colorectal cancer development. In this review, we contextualize and discuss what is known about intestinal steroidogenesis and regulation as well as the key role these functions play both in physiological and pathological conditions.

  14. Intestinal manometry: who needs it?

    PubMed Central

    Bassotti, Gabrio; Bologna, Sara; Ottaviani, Laura; Russo, Michele; Dore, Maria Pina

    2015-01-01

    The use of manometry, i.e. the recording of pressures within hollow viscera, after being successfully applied to the study of esophageal and anorectal motor dysfunctions, has also been used to investigate physiological and pathological conditions of the small bowel. By means of this technique, it has been possible to understand better the normal motor functions of the small intestine, and their relationship and variations following physiologic events, such as food ingestion. Moreover, intestinal manometry has proved useful to document motor abnormalities of the small bowel, although recognition of altered patterns specific for a determinate pathologic condition is still unavailable. However, this technique often permits the detection of abnormal gut motility in patients with abdominal symptoms such as unexplained vomiting and diarrhea, and it is sometimes also useful to address therapeutic targeting. PMID:26468344

  15. Saturated fat stimulates obesity and hepatic steatosis and affects gut microbiota composition by an enhanced overflow of dietary fat to the distal intestine.

    PubMed

    de Wit, Nicole; Derrien, Muriel; Bosch-Vermeulen, Hanneke; Oosterink, Els; Keshtkar, Shohreh; Duval, Caroline; de Vogel-van den Bosch, Johan; Kleerebezem, Michiel; Müller, Michael; van der Meer, Roelof

    2012-09-01

    We studied the effect of dietary fat type, varying in polyunsaturated-to-saturated fatty acid ratios (P/S), on development of metabolic syndrome. C57Bl/6J mice were fed purified high-fat diets (45E% fat) containing palm oil (HF-PO; P/S 0.4), olive oil (HF-OO; P/S 1.1), or safflower oil (HF-SO; P/S 7.8) for 8 wk. A low-fat palm oil diet (LF-PO; 10E% fat) was used as a reference. Additionally, we analyzed diet-induced changes in gut microbiota composition and mucosal gene expression. The HF-PO diet induced a higher body weight gain and liver triglyceride content compared with the HF-OO, HF-SO, or LF-PO diet. In the intestine, the HF-PO diet reduced microbial diversity and increased the Firmicutes-to-Bacteroidetes ratio. Although this fits a typical obesity profile, our data clearly indicate that an overflow of the HF-PO diet to the distal intestine, rather than obesity itself, is the main trigger for these gut microbiota changes. A HF-PO diet-induced elevation of lipid metabolism-related genes in the distal small intestine confirmed the overflow of palm oil to the distal intestine. Some of these lipid metabolism-related genes were previously already associated with the metabolic syndrome. In conclusion, our data indicate that saturated fat (HF-PO) has a more stimulatory effect on weight gain and hepatic lipid accumulation than unsaturated fat (HF-OO and HF-SO). The overflow of fat to the distal intestine on the HF-PO diet induced changes in gut microbiota composition and mucosal gene expression. We speculate that both are directly or indirectly contributive to the saturated fat-induced development of obesity and hepatic steatosis.

  16. Intestinal obstruction

    MedlinePlus

    ... of the bowel may be due to: A mechanical cause, which means something is in the way ... lung disease Use of certain medicines, especially narcotics Mechanical causes of intestinal obstruction may include: Adhesions or ...

  17. A Simple, Inexpensive Method for the Measurement of in vivo Intestinal Activity.

    ERIC Educational Resources Information Center

    Sallee, V. L.; Gaugl, J. F.

    1980-01-01

    Describes a system that monitors intestinal motility in vivo which is very sensitive, minimally injurious to the tissue, and inexpensive. Used are two balloons, one of which is inserted into the intestinal lumen and the other suspended from a force transducer. (CS)

  18. Relationship between dietary-induced changes in intestinal commensal microflora and duodenojejunal myoelectric activity monitored by radiotelemetry in the rat in vivo.

    PubMed

    Lesniewska, V; Rowland, I; Laerke, H N; Grant, G; Naughton, P J

    2006-01-01

    Interdigestive intestinal motility, and especially phase III of the migrating myoelectric/motor complex (MMC), is responsible for intestinal clearance and plays an important role in prevention of bacterial overgrowth and translocation in the gut. Yet previous results from gnotobiotic rats have shown that intestinal microflora can themselves affect the characteristics of the myoelectric activity of the gut during the interdigestive state. Given that the composition of the intestinal microflora can be altered by dietary manipulations, we investigated the effect of supplementation of the diet with synbiotics on intestinal microflora structure and the duodenojejunal myoelectric activity in the rat. To reduce animal distress caused by restraint and handling, which can itself affect GI motility, we applied radiotelemetry for duodenojejunal EMG recordings in conscious, freely moving rats. Thirty 16-month-old Spraque-Dawley rats were used. The diet for 15 rats (E group) was supplemented with chicory inulin, Lactobacillus rhamnosus and Bifidobacterium lactis. The remaining 15 rats were fed control diet without supplements (C group). Three rats from each group were implanted with three bipolar electrodes positioned at 2, 14 and 28 cm distal to the pylorus. After recovery, two 6 h recordings of duodenojejunal EMG were carried out on each operated rat. Subsequently, group C rats received feed supplements and group E rats received only control diet for 1 week, and an additional two 6 h recordings were carried out on each of these rats. Non-operated C and E rats were killed and samples of GI tract were collected for microbiological analyses. Supplementation of the diet with the pro- and prebiotics mixture increased the number of bifidobacteria, whereas it decreased the number of enterobacteria in jejunum, ileum, caecum and colon. In both caecum and colon, the dietary supplementation increased the number of total anaerobes and lactobacilli. Treatment with synbiotics increased

  19. [Intestinal hemorrhage due to multiple phlebectasias of the small intestine].

    PubMed

    Hammentgen, R; Kober, R; Beckmann, W; Lützeler, J

    1987-03-13

    A 37-year-old man had recurrent intestinal bleeding and resulting chronic anemia from multiple phlebectasias of the small intestine. Contrast medium studies and endoscopy of the intestine were negative. Abdominal angiography, however, demonstrated phlebectasias in the region supplied by the jejunal arteries. At operation and on examination of a resected portion of the jejunum, these multiple phlebectasias were demonstrated. Resection of the worst affected portion of the jejunum with end-to-end anastomosis was without complications postoperatively, the benzidine test on faeces was negative, and the blood-hemoglobin level gradually rose. Since radiological examination with contrast media and endoscopy are often negative in bleedings from vascular malformations of the intestine, abdominal angiography should be performed in case of intestinal bleedings not diagnosed by other methods.

  20. The outer mucus layer hosts a distinct intestinal microbial niche

    PubMed Central

    Li, Hai; Limenitakis, Julien P.; Fuhrer, Tobias; Geuking, Markus B.; Lawson, Melissa A.; Wyss, Madeleine; Brugiroux, Sandrine; Keller, Irene; Macpherson, Jamie A.; Rupp, Sandra; Stolp, Bettina; Stein, Jens V.; Stecher, Bärbel; Sauer, Uwe; McCoy, Kathy D.; Macpherson, Andrew J.

    2015-01-01

    The overall composition of the mammalian intestinal microbiota varies between individuals: within each individual there are differences along the length of the intestinal tract related to host nutrition, intestinal motility and secretions. Mucus is a highly regenerative protective lubricant glycoprotein sheet secreted by host intestinal goblet cells; the inner mucus layer is nearly sterile. Here we show that the outer mucus of the large intestine forms a unique microbial niche with distinct communities, including bacteria without specialized mucolytic capability. Bacterial species present in the mucus show differential proliferation and resource utilization compared with the same species in the intestinal lumen, with high recovery of bioavailable iron and consumption of epithelial-derived carbon sources according to their genome-encoded metabolic repertoire. Functional competition for existence in this intimate layer is likely to be a major determinant of microbiota composition and microbial molecular exchange with the host. PMID:26392213

  1. Physiological and pathophysiological factors affecting the expression and activity of the drug transporter MRP2 in intestine. Impact on its function as membrane barrier.

    PubMed

    Arana, Maite R; Tocchetti, Guillermo N; Rigalli, Juan P; Mottino, Aldo D; Villanueva, Silvina S M

    2016-07-01

    The gastrointestinal epithelium functions as a selective barrier to absorb nutrients, electrolytes and water, but at the same time restricts the passage into the systemic circulation of intraluminal potentially toxic compounds. This epithelium maintains its selective barrier function through the presence of very selective and complex intercellular junctions and the ability of the absorptive cells to reject those compounds. Accordingly, the enterocytes metabolize orally incorporated xenobiotics and secrete the hydrophilic metabolites back into the intestinal lumen through specific transporters localized apically. In the recent decades, there has been increasing recognition of the existence of the intestinal cellular barrier. In the present review we focus on the role of the multidrug resistance-associated protein 2 (MRP2, ABCC2) in the apical membrane of the enterocytes, as an important component of this intestinal barrier, as well as on its regulation. We provide a detailed compilation of significant contributions demonstrating that MRP2 expression and function vary under relevant physiological and pathophysiological conditions. Because MRP2 activity modulates the availability and pharmacokinetics of many therapeutic drugs administered orally, their therapeutic efficacy and safety may vary as well. PMID:27109321

  2. Gliding motility in bacteria: insights from studies of Myxococcus xanthus.

    PubMed

    Spormann, A M

    1999-09-01

    motor in M. xanthus controls cell movement in groups (S-motility system). It is dependent on functional type IV pili and is operative only when cells are in close proximity to each other. Type IV pili are known to be involved in another mode of bacterial surface translocation, called twitching motility. S-motility may well represent a variation of twitching motility in M. xanthus. However, twitching differs from gliding since it involves cell movements that are jerky and abrupt and that lack the organization and smoothness observed in gliding. Components of this motor are encoded by genes of the S-system, which appear to be homologs of genes involved in the biosynthesis, assembly, and function of type IV pili in Pseudomonas aeruginosa and Neisseria gonorrhoeae. How type IV pili generate force in S-motility is currently unknown, but it is to be expected that ongoing physiological, genetic, and biochemical studies in M. xanthus, in conjunction with studies on twitching in P. aeruginosa and N. gonorrhoeae, will provide important insights into this microbial motor. The two motility systems of M. xanthus are affected to different degrees by the MglA protein, which shows similarity to a small GTPase. Bacterial chemotaxis-like sensory transduction systems control gliding motility in M. xanthus. The frz genes appear to regulate gliding movement of individual cells and movement by the S-motility system, suggesting that the two motors found in this bacterium can be regulated to result in coordinated multicellular movements. In contrast, the dif genes affect only S-system-dependent swarming.

  3. Gliding Motility in Bacteria: Insights from Studies of Myxococcus xanthus

    PubMed Central

    Spormann, Alfred M.

    1999-01-01

    motor in M. xanthus controls cell movement in groups (S-motility system). It is dependent on functional type IV pili and is operative only when cells are in close proximity to each other. Type IV pili are known to be involved in another mode of bacterial surface translocation, called twitching motility. S-motility may well represent a variation of twitching motility in M. xanthus. However, twitching differs from gliding since it involves cell movements that are jerky and abrupt and that lack the organization and smoothness observed in gliding. Components of this motor are encoded by genes of the S-system, which appear to be homologs of genes involved in the biosynthesis, assembly, and function of type IV pili in Pseudomonas aeruginosa and Neisseria gonorrhoeae. How type IV pili generate force in S-motility is currently unknown, but it is to be expected that ongoing physiological, genetic, and biochemical studies in M. xanthus, in conjunction with studies on twitching in P. aeruginosa and N. gonorrhoeae, will provide important insights into this microbial motor. The two motility systems of M. xanthus are affected to different degrees by the MglA protein, which shows similarity to a small GTPase. Bacterial chemotaxis-like sensory transduction systems control gliding motility in M. xanthus. The frz genes appear to regulate gliding movement of individual cells and movement by the S-motility system, suggesting that the two motors found in this bacterium can be regulated to result in coordinated multicellular movements. In contrast, the dif genes affect only S-system-dependent swarming. PMID:10477310

  4. Technique of Functional and Motility Test: How to Perform Antroduodenal Manometry

    PubMed Central

    Patcharatrakul, Tanisa

    2013-01-01

    Antroduodenal manometry is one of the methods to evaluate stomach and duodenal motility. This test is a valuable diagnostic tool for gastrointestinal motility disorders especially small intestinal pseudo-obstruction which is difficult to make definite diagnosis by clinical manifestations or radiologic findings. Manometric findings that have no evidence of mechanical obstruction and suggestive of pseudo-obstruction with neuropathy or myopathy can avoid unnecessary surgery and the treatment can be directly targeted. Moreover, among patients who have clinically suspected small intestinal pseudo-obstruction but with normal manometric findings, the alternative diagnosis including psychiatric disorder or other organic disease should be considered. The application of this test to the patients with functional gastrointestinal symptoms especially to find the association of motor abnormalities to the symptom has less impressive yield. Antroduodenal manometry is now readily available only in some tertiary care centers. The aim of this review is to describe the antroduodenal manometry technique, interpretation and clinical utility. PMID:23875108

  5. Neuroenteric Staining as a Tool in the Evaluation of Pediatric Motility Disorders.

    PubMed

    Waseem, Shamaila H; Idrees, Muhammed T; Croffie, Joseph M

    2015-08-01

    The diagnosis of enteric neuromuscular disorders has come a long way since the first description of an enteric neuropathic disorder by the Danish physician Harald Hirschsprung in 1886. Advances in specialized enteric histopathological staining techniques have made it possible to identify subtle neuropathies and myopathies that cause intestinal motility disorders, from the common and now better understood and relatively easily diagnosed Hirschsprung's disease to the less common and more severe and not well-characterized chronic idiopathic intestinal pseudoobstruction, which continues to present a diagnostic challenge to the gastroenterologist and histopathologist alike. This article will discuss the common gastrointestinal motility disorders and some of the specialized histological stains, such as the relatively common enzyme stain, acetylcholinesterase, used to diagnose Hirschsprung's disease; advanced tinctorial stains, such as Masson trichrome, which may aid in diagnosis of enteric myopathies causing pseudoobstruction; and immunohistochemical stains such as C-Kit or PG 9.5, which may aid in the diagnosis of enteric neuropathies causing pseudoobstruction.

  6. Probiotic supplementation affects markers of intestinal barrier, oxidation, and inflammation in trained men; a randomized, double-blinded, placebo-controlled trial

    PubMed Central

    2012-01-01

    Background Probiotics are an upcoming group of nutraceuticals claiming positive effects on athlete’s gut health, redox biology and immunity but there is lack of evidence to support these statements. Methods We conducted a randomized, double-blinded, placebo controlled trial to observe effects of probiotic supplementation on markers of intestinal barrier, oxidation and inflammation, at rest and after intense exercise. 23 trained men received multi-species probiotics (1010 CFU/day, Ecologic®Performance or OMNi-BiOTiC®POWER, n = 11) or placebo (n = 12) for 14 weeks and performed an intense cycle ergometry over 90 minutes at baseline and after 14 weeks. Zonulin and α1-antitrypsin were measured from feces to estimate gut leakage at baseline and at the end of treatment. Venous blood was collected at baseline and after 14 weeks, before and immediately post exercise, to determine carbonyl proteins (CP), malondialdehyde (MDA), total oxidation status of lipids (TOS), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6). Statistical analysis used multifactorial analysis of variance (ANOVA). Level of significance was set at p < 0.05, a trend at p < 0.1. Results Zonulin decreased with supplementation from values slightly above normal into normal ranges (<30 ng/ml) and was significantly lower after 14 weeks with probiotics compared to placebo (p = 0.019). We observed no influence on α1-antitrypsin (p > 0.1). CP increased significantly from pre to post exercise in both groups at baseline and in the placebo group after 14 weeks of treatment (p = 0.006). After 14 weeks, CP concentrations were tendentially lower with probiotics (p = 0.061). TOS was slightly increased above normal in both groups, at baseline and after 14 weeks of treatment. There was no effect of supplementation or exercise on TOS. At baseline, both groups showed considerably higher TNF-α concentrations than normal. After 14 weeks TNF-α was

  7. Elastic mismatch enhances cell motility

    NASA Astrophysics Data System (ADS)

    Bresler, Yony; Palmieri, Benoit; Grant, Martin

    In recent years, the study of physics phenomena in cancer has drawn considerable attention. In cancer metastasis, a soft cancer cell leaves the tumor, and must pass through the endothelium before reaching the bloodstream. Using a phase-field model we have shown that the elasticity mismatch between cells alone is sufficient to enhance the motility of thesofter cancer cell by means of bursty migration, in agreement with experiment. We will present further characterization of these behaviour, as well as new possible applications for this model.

  8. Correlation of cell membrane dynamics and cell motility

    PubMed Central

    2011-01-01

    Background Essential events of cell development and homeostasis are revealed by the associated changes of cell morphology and therefore have been widely used as a key indicator of physiological states and molecular pathways affecting various cellular functions via cytoskeleton. Cell motility is a complex phenomenon primarily driven by the actin network, which plays an important role in shaping the morphology of the cells. Most of the morphology based features are approximated from cell periphery but its dynamics have received none to scant attention. We aim to bridge the gap between membrane dynamics and cell states from the perspective of whole cell movement by identifying cell edge patterns and its correlation with cell dynamics. Results We present a systematic study to extract, classify, and compare cell dynamics in terms of cell motility and edge activity. Cell motility features extracted by fitting a persistent random walk were used to identify the initial set of cell subpopulations. We propose algorithms to extract edge features along the entire cell periphery such as protrusion and retraction velocity. These constitute a unique set of multivariate time-lapse edge features that are then used to profile subclasses of cell dynamics by unsupervised clustering. Conclusions By comparing membrane dynamic patterns exhibited by each subclass of cells, correlated trends of edge and cell movements were identified. Our findings are consistent with published literature and we also identified that motility patterns are influenced by edge features from initial time points compared to later sampling intervals. PMID:22372978

  9. Divalent Cation Control of Flagellar Motility in African Trypanosomes

    NASA Astrophysics Data System (ADS)

    Westergard, Anna M.; Hutchings, Nathan R.

    2005-03-01

    Changes in calcium concentration have been shown to dynamically affect flagellar motility in several eukaryotic systems. The African trypanosome is a monoflagellated protozoan parasite and the etiological agent of sleeping sickness. Although cell motility has been implicated in disease progression, very little is currently known about biochemical control of the trypanosome flagellum. In this study, we assess the effects of extracellular changes in calcium and nickel concentration on trypanosome flagellar movement. Using a flow through chamber, we determine the relative changes in motility in individual trypanosomes in response to various concentrations of calcium and nickel, respectively. Extracellular concentrations of calcium and nickel (as low as 100 micromolar) significantly inhibit trypanosome cell motility. The effects are reversible, as indicated by the recovery of motion after removal of the calcium or nickel from the chamber. We are currently investigating the specific changes in flagellar oscillation and coordination that result from calcium and nickel, respectively. These results verify the presence of a calcium-responsive signaling mechanism(s) that regulates flagellar beat in trypanosomes.

  10. Vimentin intermediate filaments modulate the motility of mitochondria.

    PubMed

    Nekrasova, Oxana E; Mendez, Melissa G; Chernoivanenko, Ivan S; Tyurin-Kuzmin, Pyotr A; Kuczmarski, Edward R; Gelfand, Vladimir I; Goldman, Robert D; Minin, Alexander A

    2011-07-01

    Interactions with vimentin intermediate filaments (VimIFs) affect the motility, distribution, and anchorage of mitochondria. In cells lacking VimIFs or in which VimIF organization is disrupted, the motility of mitochondria is increased relative to control cells that express normal VimIF networks. Expression of wild-type VimIF in vimentin-null cells causes mitochondrial motility to return to normal (slower) rates. In contrast, expressing vimentin with mutations in the mid-region of the N-terminal non-α-helical domain (deletions of residues 41-96 or 45-70, or substitution of Pro-57 with Arg) did not inhibit mitochondrial motility even though these mutants retain their ability to assemble into VimIFs in vivo. It was also found that a vimentin peptide consisting of residues 41-94 localizes to mitochondria. Taken together, these data suggest that VimIFs bind directly or indirectly to mitochondria and anchor them within the cytoplasm.

  11. Mechanism of Actin-Based Motility

    NASA Astrophysics Data System (ADS)

    Pantaloni, Dominique; Le Clainche, Christophe; Carlier, Marie-France

    2001-05-01

    Spatially controlled polymerization of actin is at the origin of cell motility and is responsible for the formation of cellular protrusions like lamellipodia. The pathogens Listeria monocytogenes and Shigella flexneri, which undergo actin-based propulsion, are acknowledged models of the leading edge of lamellipodia. Actin-based motility of the bacteria or of functionalized microspheres can be reconstituted in vitro from only five pure proteins. Movement results from the regulated site-directed treadmilling of actin filaments, consistent with observations of actin dynamics in living motile cells and with the biochemical properties of the components of the synthetic motility medium.

  12. Bursts of non-deglutitive simultaneous contractions may be a normal oesophageal motility pattern.

    PubMed Central

    Janssens, J; Annese, V; Vantrappen, G

    1993-01-01

    The frequency and characteristics of non-deglutitive motor activity of the human oesophagus and its relation to motility patterns in the antrum and upper small intestine were studied in 25 fasted healthy subjects. Motility of the oesophagus, antrum, and upper small intestine was recorded by means of a manometric perfused catheter system. The most striking non-deglutitive motility pattern consisted of repetitive bursts of non-sequential pressure peaks occurring in the smooth muscle portion of the oesophagus. The mean number of pressure peaks per burst was 2.7 (SD 2) waves with a mean amplitude of 19.5 (SD 9.9) mm Hg and a duration of 3.09 (SD 0.22) seconds. The highest amplitude was 80 mm Hg and the longest burst consisted of 13 repetitive waves. The bursts were recorded up to a distance of 15-20 cm above the lower oesophageal sphincter. Ninety five per cent of the bursts occurred during a 15 minute period before the onset of phase 3 of the migrating motor complex in the antral or upper small intestinal area, or during the lower oesophageal sphincter component of the migrating motor complex. In conclusion, spontaneous bursts of non-sequential pressure peaks occurred in the smooth muscle part of the human oesophagus in relation to phase 3 of the migrating motor complex. They represent the oesophageal body component of phase 3 of the migrating motor complex and are not a sign of oesophageal motor abnormalities. PMID:8174946

  13. High or low dietary carbohydrate:protein ratios during first-feeding affect glucose metabolism and intestinal microbiota in juvenile rainbow trout.

    PubMed

    Geurden, I; Mennigen, J; Plagnes-Juan, E; Veron, V; Cerezo, T; Mazurais, D; Zambonino-Infante, J; Gatesoupe, J; Skiba-Cassy, S; Panserat, S

    2014-10-01

    Based on the concept of nutritional programming in mammals, we tested whether an acute hyperglucidic-hypoproteic stimulus during first feeding could induce long-term changes in nutrient metabolism in rainbow trout. Trout alevins received during the five first days of exogenous feeding either a hyperglucidic (40% gelatinized starch + 20% glucose) and hypoproteic (20%) diet (VLP diet) or a high-protein (60%) glucose-free diet (HP diet, control). Following a common 105-day period on a commercial diet, both groups were then challenged (65 days) with a carbohydrate-rich diet (28%). Short- and long-term effects of the early stimuli were evaluated in terms of metabolic marker gene expressions and intestinal microbiota as initial gut colonisation is essential for regulating the development of the digestive system. In whole alevins (short term), diet VLP relative to HP rapidly increased gene expressions of glycolytic enzymes, while those involved in gluconeogenesis and amino acid catabolism decreased. However, none of these genes showed persistent molecular adaptation in the liver of challenged juveniles (long term). By contrast, muscle of challenged juveniles subjected previously to the VLP stimulus displayed downregulated expression of markers of glycolysis and glucose transport (not seen in the short term). These fish also had higher plasma glucose (9 h postprandial), suggesting impaired glucose homeostasis induced by the early stimulus. The early stimulus did not modify the expression of the analysed metabolism-related microRNAs, but had short- and long-term effects on intestinal fungi (not bacteria) profiles. In summary, our data show that a short hyperglucidic-hypoproteic stimulus during early life may have a long-term influence on muscle glucose metabolism and intestinal microbiota in trout.

  14. Dietary administration of microalgae alone or supplemented with Lactobacillus sakei affects immune response and intestinal morphology of Pacific red snapper (Lutjanus peru).

    PubMed

    Reyes-Becerril, Martha; Angulo, Carlos; Estrada, Norma; Murillo, Ylenia; Ascencio-Valle, Felipe

    2014-09-01

    The aim of this study was to evaluate the effect of dietary microalgae Navicula sp single or in combination with Lactobacillus sakei on growth performance, humoral immune parameters and intestinal morphology in Pacific red snapper, Lutjanus peru. The experimental fish were grouped into four treatment diets which were a control diet (commercial diet, Control), silage microalgae Navicula sp plus L. sakei (10(6) CFU g(-1), Navicula + L. sakei), lyophilized microalgae (Navicula) and L. sakei (10(6) CFU g(-1), L. sakei). The blood and intestine samples were collected on week 4 and 8. The weight gain showed an additive effect of Navicula + L. sakei at 8 weeks of treatment compared with fish fed control diet. Overall, physiological parameters such as total protein and hemoglobin were increased in fish fed with Navicula and L. sakei diets at 4 and 8 weeks of feeding assay, respectively. There was a significant improvement in immune parameters, principally in myeloperoxidase, lysozyme, total antiproteases activities and IgM in fish fed with Navicula + L. sakei and L. sakei diets at 4 or 8 weeks of treatments. Serum antioxidant capabilities revealed significant increase in phosphatase alkaline, esterase, protease, superoxide dismutase and catalase in groups which received diet supplemented with Navicula + L. sakei and L. sakei diets. Finally, light microscopy observations revealed no effect of experimental diets on microvilli height. Curiously, the presence of vacuoles inside the enterocytes was significant higher in the intestine of L. sakei group after four or six weeks of feeding. Elevated intraepithelial leucocyte levels and melanomacrophages centers were observed in fish fed Navicula or control diets at any time of the experiment. To conclude, the results of the present study demonstrate that the fish that were fed with Navicula + L. sakei or L. sakei diets yielded significantly better immune status and antioxidant capabilities.

  15. High or low dietary carbohydrate:protein ratios during first-feeding affect glucose metabolism and intestinal microbiota in juvenile rainbow trout.

    PubMed

    Geurden, I; Mennigen, J; Plagnes-Juan, E; Veron, V; Cerezo, T; Mazurais, D; Zambonino-Infante, J; Gatesoupe, J; Skiba-Cassy, S; Panserat, S

    2014-10-01

    Based on the concept of nutritional programming in mammals, we tested whether an acute hyperglucidic-hypoproteic stimulus during first feeding could induce long-term changes in nutrient metabolism in rainbow trout. Trout alevins received during the five first days of exogenous feeding either a hyperglucidic (40% gelatinized starch + 20% glucose) and hypoproteic (20%) diet (VLP diet) or a high-protein (60%) glucose-free diet (HP diet, control). Following a common 105-day period on a commercial diet, both groups were then challenged (65 days) with a carbohydrate-rich diet (28%). Short- and long-term effects of the early stimuli were evaluated in terms of metabolic marker gene expressions and intestinal microbiota as initial gut colonisation is essential for regulating the development of the digestive system. In whole alevins (short term), diet VLP relative to HP rapidly increased gene expressions of glycolytic enzymes, while those involved in gluconeogenesis and amino acid catabolism decreased. However, none of these genes showed persistent molecular adaptation in the liver of challenged juveniles (long term). By contrast, muscle of challenged juveniles subjected previously to the VLP stimulus displayed downregulated expression of markers of glycolysis and glucose transport (not seen in the short term). These fish also had higher plasma glucose (9 h postprandial), suggesting impaired glucose homeostasis induced by the early stimulus. The early stimulus did not modify the expression of the analysed metabolism-related microRNAs, but had short- and long-term effects on intestinal fungi (not bacteria) profiles. In summary, our data show that a short hyperglucidic-hypoproteic stimulus during early life may have a long-term influence on muscle glucose metabolism and intestinal microbiota in trout. PMID:25274323

  16. Starvation-Induced Changes in Motility, Chemotaxis, and Flagellation of Rhizobium meliloti†

    PubMed Central

    Wei, Xueming; Bauer, Wolfgang D.

    1998-01-01

    The changes in motility, chemotactic responsiveness, and flagellation of Rhizobium meliloti RMB7201, L5-30, and JJ1c10 were analyzed after transfer of the bacteria to buffer with no available C, N, or phosphate. Cells of these three strains remained viable for weeks after transfer to starvation buffer (SB) but lost all motility within just 8 to 72 h after transfer to SB. The rates of motility loss differed by severalfold among the strains. Each strain showed a transient, two- to sixfold increase in chemotactic responsiveness toward glutamine within a few hours after transfer to SB, even though motility dropped substantially during the same period. Strains L5-30 and JJ1c10 also showed increased responsiveness to the nonmetabolizable chemoattractant cycloleucine. Cycloleucine partially restored the motility of starving cells when added after transfer and prevented the loss of motility when included in the SB used for initial suspension of the cells. Thus, interactions between chemoattractants and their receptors appear to affect the regulation of motility in response to starvation independently of nutrient or energy source availability. Electron microscopic observations revealed that R. meliloti cells lost flagella and flagellar integrity during starvation, but not as fast, nor to such a great extent, as the cells lost motility. Even after prolonged starvation, when none of the cells were actively motile, about one-third to one-half of the initially flagellated cells retained some flagella. Inactivation of flagellar motors therefore appears to be a rapid and important response of R. meliloti to starvation conditions. Flagellar-motor inactivation was at least partially reversible by addition of either cycloleucine or glucose. During starvation, some cells appeared to retain normal flagellation, normal motor activity, or both for relatively long periods while other cells rapidly lost flagella, motor activity, or both, indicating that starvation-induced regulation of

  17. Chemotactic Motility of Pseudomonas fluorescens F113 under Aerobic and Denitrification Conditions

    PubMed Central

    Redondo-Nieto, Miguel; Rivilla, Rafael; Martín, Marta

    2015-01-01

    The sequence of the genome of Pseudomonas fluorescens F113 has shown the presence of multiple traits relevant for rhizosphere colonization and plant growth promotion. Among these traits are denitrification and chemotactic motility. Besides aerobic growth, F113 is able to grow anaerobically using nitrate and nitrite as final electron acceptors. F113 is able to perform swimming motility under aerobic conditions and under anaerobic conditions when nitrate is used as the electron acceptor. However, nitrite can not support swimming motility. Regulation of swimming motility is similar under aerobic and anaerobic conditions, since mutants that are hypermotile under aerobic conditions, such as gacS, sadB, kinB, algU and wspR, are also hypermotile under anaerobic conditions. However, chemotactic behavior is different under aerobic and denitrification conditions. Unlike most pseudomonads, the F113 genome encode three complete chemotaxis systems, Che1, Che2 and Che3. Mutations in each of the cheA genes of the three Che systems has shown that the three systems are functional and independent. Mutation of the cheA1 gene completely abolished swimming motility both under aerobic and denitrification conditions. Mutation of the cheA2 gene, showed only a decrease in swimming motility under both conditions, indicating that this system is not essential for chemotactic motility but is necessary for optimal motility. Mutation of the cheA3 gene abolished motility under denitrification conditions but only produced a decrease in motility under aerobic conditions. The three Che systems proved to be implicated in competitive rhizosphere colonization, being the cheA1 mutant the most affected. PMID:26161531

  18. Intestinal protozoan infections in Malaysia.

    PubMed

    Lai, K P

    1992-12-01

    Intestinal protozoa are found in all communities in Malaysia and among all ethnic groups. Prevalence of intestinal protozoa is not affected by ethnicity but by living conditions. Communities with both basic amenities of safe water supply and proper toilets have lower prevalence than those with one or none of the amenity. Cryptosporidium is an important intestinal protozoon in Malaysia and should be included in future field and laboratory studies and also in laboratory diagnosis for pathogens. Much interest will be centered on Blastocystis hominis in future studies in view that it may be a cause of diarrhea. PMID:1298065

  19. Intestinal protozoan infections in Malaysia.

    PubMed

    Lai, K P

    1992-12-01

    Intestinal protozoa are found in all communities in Malaysia and among all ethnic groups. Prevalence of intestinal protozoa is not affected by ethnicity but by living conditions. Communities with both basic amenities of safe water supply and proper toilets have lower prevalence than those with one or none of the amenity. Cryptosporidium is an important intestinal protozoon in Malaysia and should be included in future field and laboratory studies and also in laboratory diagnosis for pathogens. Much interest will be centered on Blastocystis hominis in future studies in view that it may be a cause of diarrhea.

  20. Intestinal Obstruction

    MedlinePlus

    ... the small intestine (duodenum) may be caused by cancer of the pancreas, scarring from an ulcer, or Crohn disease . Rarely, a gallstone, a mass of undigested food, or a collection of parasitic worms may block ... commonly caused by cancer, diverticulitis , or a hard lump of stool (fecal ...

  1. Inhibitory Effects and Sympathetic Mechanisms of Distension in the Distal Organs on Small Bowel Motility and Slow Waves in Canine.

    PubMed

    Song, Jun; Yin, Jieyun; Chen, Jiande D Z

    2015-12-01

    Rectal distension (RD) is known to induce intestinal dysmotility. Few studies were performed to compare effects of RD, colon distension (CD) and duodenal distension (DD) on small bowel motility. This study aimed to investigate effects and underlying mechanisms of distensions in these regions on intestinal motility and slow waves. Eight dogs chronically implanted with a duodenal fistula, a proximal colon fistula, and intestinal serosal electrodes were studied in six sessions: control, RD, CD, DD, RD + guanethidine, and CD + guanethidine. Postprandial intestinal contractions and slow waves were recorded for the assessment of intestinal motility. The electrocardiogram was recorded for the assessment of autonomic functions. (1) Isobaric RD and CD suppressed intestinal contractions (contractile index: 6.0 ± 0.4 with RD vs. 9.9 ± 0.9 at baseline, P = 0.001, 5.3 ± 0.2 with CD vs. 7.7 ± 0.8 at baseline, P = 0.008). Guanethidine at 3 mg/kg iv was able to partially block the effects. (2) RD and CD reduced the percentage of normal intestinal slow waves from 92.1 ± 2.8 to 64.2 ± 3.4 % (P < 0.001) and from 90 ± 2.7 to 69.2 ± 3.7 % (P = 0.01), respectively. Guanethidine could eliminate these inhibitory effects. (3) DD did not induce any changes in small intestinal contractions and slow waves (P > 0.05). (4) The spectral analysis of the heart rate variability showed that both RD and CD increased sympathetic activity (LF) and reduced vagal activity (HF) (P < 0.05). Isobaric RD and CD could inhibit postprandial intestinal motility and impair intestinal slow waves, which were mediated via the sympathetic pathway. However, DD at a site proximal to the measurement site did not seem to impair small intestinal contractions or slow waves.

  2. Will Lipidation of ApoA1 through Interaction with ABCA1 at the Intestinal Level Affect the Protective Functions of HDL?

    PubMed Central

    Niesor, Eric J.

    2015-01-01

    The relationship between levels of high-density lipoprotein cholesterol (HDL-C) and cardiovascular (CV) risk is well recognized; however, in recent years, large-scale phase III studies with HDL-C-raising or -mimicking agents have failed to demonstrate a clinical benefit on CV outcomes associated with raising HDL-C, casting doubt on the “HDL hypothesis.” This article reviews potential reasons for the observed negative findings with these pharmaceutical compounds, focusing on the paucity of translational models and relevant biomarkers related to HDL metabolism that may have confounded understanding of in vivo mechanisms. A unique function of HDL is its ability to interact with the ATP-binding cassette transporter (ABC) A1 via apolipoprotein (Apo) A1. Only recently, studies have shown that this process may be involved in the intestinal uptake of dietary sterols and antioxidants (vitamin E, lutein and zeaxanthin) at the basolateral surface of enterocytes. This parameter should be assessed for HDL-raising drugs in addition to the more documented reverse cholesterol transport (RCT) from peripheral tissues to the liver. Indeed, a single mechanism involving the same interaction between ApoA1 and ABCA1 may encompass two HDL functions previously considered as separate: antioxidant through the intestinal uptake of antioxidants and RCT through cholesterol efflux from loaded cells such as macrophages. PMID:25569858

  3. Kobe earthquake and reduced sperm motility.

    PubMed

    Fukuda, M; Fukuda, K; Shimizu, T; Yomura, W; Shimizu, S

    1996-06-01

    We investigated a possible relationship between the Kobe earthquake (January 17, 1995) and the quality of semen. We assessed sperm concentration and motility of 27 male patients who had a concentration of more than 30 million/ml and >40% sperm motility within 5 months before the earthquake. Twelve male patients from districts with a magnitude of <4 on the Richter scale showed no difference in sperm concentration and motility before and after the earthquake. Of 15 male patients from districts with a magnitude of >6, five patients whose houses received no damage showed no distinct changes in sperm concentration and motility. In contrast, 10 patients whose houses were partially or completely destroyed showed significantly (P < 0.001) lower sperm motility after the earthquake than before, although no significant difference of sperm concentration could be observed. Of these latter 10 patients, seven could be followed. In six patients, sperm motility was restored between 2 and 9 months after the earthquake; the sperm motility in one patient, whose father died a victim of the house crash, has not yet recovered. Thus, the acute stress resulting from such a catastrophic earthquake could be a possible cause of reduced sperm motility.

  4. Effects of Lizhong Tang on gastrointestinal motility in mice

    PubMed Central

    Lee, Min Cheol; Ha, Wooram; Park, Jinhyeong; Kim, Junghoon; Jung, Yunjin; Kim, Byung Joo

    2016-01-01

    AIM To investigate the effects of Lizhong Tang, a traditional Chinese medicine formula, on gastrointestinal motility in mice. METHODS The in vivo effects of Lizhong Tang on GI motility were investigated by measuring the intestinal transit rates (ITRs) and gastric emptying (GE) values in normal mice and in mice with experimentally induced GI motility dysfunction (GMD). RESULTS In normal ICR mice, the ITR and GE values were significantly and dose-dependently increased by Lizhong Tang (ITR values: 54.4% ± 1.9% vs 65.2% ± 1.8%, P < 0.01 with 0.1 g/kg Lizhong Tang and 54.4% ± 1.9% vs 83.8% ± 1.9%, P < 0.01 with 1 g/kg Lizhong Tang; GE values: 60.7% ± 1.9% vs 66.8% ± 2.1%, P < 0.05 with 0.1 g/kg Lizhong Tang and 60.7% ± 1.9% vs 72.5% ± 1.7%, P < 0.01 with 1 g/kg Lizhong Tang). The ITRs of the GMD mice were significantly reduced compared with those of the normal mice, which were significantly and dose-dependently reversed by Lizhong Tang. Additionally, in loperamide- and cisplatin-induced models of GE delay, Lizhong Tang administration reversed the GE deficits. CONCLUSION These results suggest that Lizhong Tang may be a novel candidate for development as a prokinetic treatment for the GI tract. PMID:27678361

  5. Effects of Lizhong Tang on gastrointestinal motility in mice

    PubMed Central

    Lee, Min Cheol; Ha, Wooram; Park, Jinhyeong; Kim, Junghoon; Jung, Yunjin; Kim, Byung Joo

    2016-01-01

    AIM To investigate the effects of Lizhong Tang, a traditional Chinese medicine formula, on gastrointestinal motility in mice. METHODS The in vivo effects of Lizhong Tang on GI motility were investigated by measuring the intestinal transit rates (ITRs) and gastric emptying (GE) values in normal mice and in mice with experimentally induced GI motility dysfunction (GMD). RESULTS In normal ICR mice, the ITR and GE values were significantly and dose-dependently increased by Lizhong Tang (ITR values: 54.4% ± 1.9% vs 65.2% ± 1.8%, P < 0.01 with 0.1 g/kg Lizhong Tang and 54.4% ± 1.9% vs 83.8% ± 1.9%, P < 0.01 with 1 g/kg Lizhong Tang; GE values: 60.7% ± 1.9% vs 66.8% ± 2.1%, P < 0.05 with 0.1 g/kg Lizhong Tang and 60.7% ± 1.9% vs 72.5% ± 1.7%, P < 0.01 with 1 g/kg Lizhong Tang). The ITRs of the GMD mice were significantly reduced compared with those of the normal mice, which were significantly and dose-dependently reversed by Lizhong Tang. Additionally, in loperamide- and cisplatin-induced models of GE delay, Lizhong Tang administration reversed the GE deficits. CONCLUSION These results suggest that Lizhong Tang may be a novel candidate for development as a prokinetic treatment for the GI tract.

  6. Inhibitory effects of zingerone, a pungent component of Zingiber officinale Roscoe, on colonic motility in rats.

    PubMed

    Iwami, Momoe; Shiina, Takahiko; Hirayama, Haruko; Shima, Takeshi; Takewaki, Tadashi; Shimizu, Yasutake

    2011-01-01

    Ginger (rhizome of Zingiber officinale Roscoe) is an herbal medicine for the treatment of gastrointestinal disorders including constipation and diarrhea. Zingerone is a likely active constituent responsible for the antidiarrheal activity of ginger. The current study was designed to characterize pharmacological actions of zingerone on colonic motility. To evaluate pharmacological effects of zingerone on colonic motility, we used isolated colonic segments from rats, in which mechanical responses were recorded in the longitudinal direction. In addition, we evaluated the effects on colonic motility in vivo by measuring intraluminal pressure changes and expelled fluid volume from the colon in anesthetized rats. Zingerone was applied to the lumen of the colon to allow the drug to access from the mucosal side. Zingerone inhibited spontaneous contractile movements in the isolated colonic segments in a dose-dependent manner. The inhibitory effects of zingerone on colonic movements were not affected by pretreatment with capsazepine, a typical antagonist of transient receptor potential vanilloid 1. In addition, tetrodotoxin, a blocker of voltage-dependent sodium channels on neurons, did not affect the suppression of colonic movements by zingerone, suggesting that zingerone acts on the smooth muscles directly. Zingerone also attenuated colonic motility in vivo without affecting blood pressure and heart rate. The effects were reversible and reproducible. Our findings suggest that zingerone can inhibit colonic motility via direct action on smooth muscles. Zingerone might exert beneficial therapeutic effects on hypermotility-induced diarrhea by abrogating excessive gastrointestinal motility. PMID:20799069

  7. Castanea sativa Mill. extract contracts gallbladder and relaxes sphincter of Oddi in guinea pig: a natural approach to biliary tract motility disorders.

    PubMed

    Micucci, Matteo; Ioan, Pierfranco; Aldini, Rita; Cevenini, Monica; Alvisi, Vittorio; Ruffilli, Corrado; Chiarini, Alberto; Budriesi, Roberta

    2014-07-01

    Impaired gallbladder motility is a contributing factor to gallstone formation. Since many drugs delaying intestinal motility inhibit gallbladder emptying, the aim of the present study was to evaluate the effect on gallbladder and sphincter of Oddi motility of a Natural Chestnut Wood Extract (NEC) that reduces intestinal motility. In order to evaluate the effect of the extract in normal- and high-risk gallstone conditions, the investigation was performed using tissues from animals fed normal and lithogenic diet. Fifty guinea pigs were administered either control or lithogenic diet. The spontaneous motility of the gallbladder and sphincter of Oddi were recorded on isolated gallbladder tissues; thereafter, the effect of NEC on motility was tested and compared with carbachol (CCh), potassium chloride (KCl), noradrenaline (NA), and A71623. Compared to controls, the lithogenic diet induced an irregular and disordered motor pattern in both the gallbladder and sphincter of Oddi. NEC increased gallbladder and decreased sphincter of Oddi spontaneous motility independently of cholinergic, adrenergic, and CCK-1 receptor-mediated pathways both in controls and in lithogenic diet-fed animals, although the effect was lower in the latter group. The effect was reversible and mediated by calcium channels. The natural extract of chestnut increasing gallbladder contraction and inducing the relaxation of the sphincter of Oddi can be of benefit in pathological conditions associated with increased transit time at risk of gallstones.

  8. Effect of 655 nm laser different powers on dog sperm motility parameters

    NASA Astrophysics Data System (ADS)

    Corral-Baqués, M. I.; Rigau, T.; Rivera, M. M.; Rodríguez-Gil, J. E.; Rigau, J.

    2006-04-01

    Introduction: One of the most appreciated features of the sperm is its motility, which depends on a big energy consumption despite differences among species. Laser acts direct or indirectly on mitochondria increasing ATP production. Material and method: By means of a Computer Aided Sperm Analysis (CASA) we have studied the effects of a 655 nm continuous wave diode laser irradiation at different power outputs with a dose of 3.3418 J on sperm motility. After an eosine-nigrosine stain to establish its quality, the second fraction of fresh beagle dog sperm was divided into 5 groups, 1 control and four to be irradiated respectively with an average output power of 6.84 mW, 15.43 mW, 33.05 mW and 49.66 mW. At times 0 and 45 minutes from irradiation pictures were taken and analysed with the Sperm class Analyzer SCA2002 programme. The motility parameters of 4987 spermatozoa studied were: curvilinear velocity (VCL), progressive velocity (VSL), straightness (STR), wobble (WOB), average path velocity (VAP), linearity (LIN), mean amplitude of lateral head displacement (ALHmed), beat cross frequency (BCF) and the total motility (MT). At time 15 minutes after irradiation a hypoosmotic swelling test (HOST) was done. Results: Several motility parameters that affect the overall motile sperm subpopulation structure have been changed by different output powers of a 655 nm diode laser irradiation, and prevents the decrease of the sperm motility properties along time.

  9. Bacterial signaling and motility: Sure bets

    SciTech Connect

    Zhulin, Igor B

    2008-01-01

    cytoplasmic membrane. The interaction causes the supramembrane and cytoplasmic rings to rotate along with the flagellar filaments. The energy for flagellar rotation comes from proton motive force or other ions, especially sodium in marine bacteria, which generate an electrochemical gradient across the cell membrane. Three proteins, FliM, FliN, and FliG, located at the base of the motor act as switches that control the direction of flagellar rotation. As exemplified by the enteric bacteria Escherichia coli and Salmonella enterica serovar Typhimurium, changes in the direction of flagellar rotation affect the swimming behavior of the bacterial cell. Counterclockwise (CCW) rotation of the flagella causes the flagellar filaments to form a bundle that pushes the cell forward in a 'run.' In contrast, clockwise (CW) rotation causes the flagellar bundle to fly apart, and the cell tumbles to reorient to a new direction for the ensuing run upon the return of CCW rotation. The interchanging pattern of CCW and CW rotations produces a random walk, composed of relatively long runs with occasional direction changes or turns. By modulating the lengths of the runs or the frequency of tumbling, bacteria can regulate their motile behavior to move in a desirable direction. Many bacteria can also move on surfaces. Except for flagellum-driven swarming motility, all the other forms of known bacterial surface movement involve no flagella. The flagellum-independent surface motility, known as gliding, is observed in cyanobacteria, Mycoplasma species, Cytophaga-Flexibacterium species, and Myxococcus species. Without a doubt, the most thoroughly studied model gliding bacterium is Myxococcus xanthus, which also serves as a prokaryotic model for developmental biology due to its ability to develop multicellular fruiting bodies. M. xanthus cells use gliding motility both to hunt for food during vegetative growth and to aggregate during fruiting body formation. When nutrients are present, groups of cells or

  10. An Orally Active Cannabis Extract with High Content in Cannabidiol attenuates Chemically-induced Intestinal Inflammation and Hypermotility in the Mouse

    PubMed Central

    Pagano, Ester; Capasso, Raffaele; Piscitelli, Fabiana; Romano, Barbara; Parisi, Olga A.; Finizio, Stefania; Lauritano, Anna; Marzo, Vincenzo Di; Izzo, Angelo A.; Borrelli, Francesca

    2016-01-01

    Anecdotal and scientific evidence suggests that Cannabis use may be beneficial in inflammatory bowel disease (IBD) patients. Here, we have investigated the effect of a standardized Cannabis sativa extract with high content of cannabidiol (CBD), here named CBD BDS for “CBD botanical drug substance,” on mucosal inflammation and hypermotility in mouse models of intestinal inflammation. Colitis was induced in mice by intracolonic administration of dinitrobenzenesulfonic acid (DNBS). Motility was evaluated in the experimental model of intestinal hypermotility induced by irritant croton oil. CBD BDS or pure CBD were given - either intraperitoneally or by oral gavage – after the inflammatory insult (curative protocol). The amounts of CBD in the colon, brain, and liver after the oral treatments were measured by high-performance liquid chromatography coupled to ion trap-time of flight mass spectrometry. CBD BDS, both when given intraperitoneally and by oral gavage, decreased the extent of the damage (as revealed by the decrease in the colon weight/length ratio and myeloperoxidase activity) in the DNBS model of colitis. It also reduced intestinal hypermotility (at doses lower than those required to affect transit in healthy mice) in the croton oil model of intestinal hypermotility. Under the same experimental conditions, pure CBD did not ameliorate colitis while it normalized croton oil-induced hypermotility when given intraperitoneally (in a dose-related fashion) or orally (only at one dose). In conclusion, CBD BDS, given after the inflammatory insult, attenuates injury and motility in intestinal models of inflammation. These findings sustain the rationale of combining CBD with other minor Cannabis constituents and support the clinical development of CBD BDS for IBD treatment. PMID:27757083

  11. Disruption of TgPHIL1 Alters Specific Parameters of Toxoplasma gondii Motility Measured in a Quantitative, Three-Dimensional Live Motility Assay

    PubMed Central

    Leung, Jacqueline M.; Rould, Mark A.; Konradt, Christoph; Hunter, Christopher A.; Ward, Gary E.

    2014-01-01

    T. gondii uses substrate-dependent gliding motility to invade cells of its hosts, egress from these cells at the end of its lytic cycle and disseminate through the host organism during infection. The ability of the parasite to move is therefore critical for its virulence. T. gondii engages in three distinct types of gliding motility on coated two-dimensional surfaces: twirling, circular gliding and helical gliding. We show here that motility in a three-dimensional Matrigel-based environment is strikingly different, in that all parasites move in irregular corkscrew-like trajectories. Methods developed for quantitative analysis of motility parameters along the smoothed trajectories demonstrate a complex but periodic pattern of motility with mean and maximum velocities of 0.58±0.07 µm/s and 2.01±0.17 µm/s, respectively. To test how a change in the parasite's crescent shape might affect trajectory parameters, we compared the motility of Δphil1 parasites, which are shorter and wider than wild type, to the corresponding parental and complemented lines. Although comparable percentages of parasites were moving for all three lines, the Δphil1 mutant exhibited significantly decreased trajectory lengths and mean and maximum velocities compared to the parental parasite line. These effects were either partially or fully restored upon complementation of the Δphil1 mutant. These results show that alterations in morphology may have a significant impact on T. gondii motility in an extracellular matrix-like environment, provide a possible explanation for the decreased fitness of Δphil1 parasites in vivo, and demonstrate the utility of the quantitative three-dimensional assay for studying parasite motility. PMID:24489670

  12. Intestinal spirochaetosis

    PubMed Central

    Lee, F. D.; Kraszewski, A.; Gordon, J.; Howie, J. G. R.; McSeveney, D.; Harland, W. A.

    1971-01-01

    An abnormal condition of the large intestine is described in which the surface epithelium is infested by short spirochaetes. Diagnosis can be made by light microscopy. A review of 14 cases diagnosed by rectal biopsy and 62 cases involving the appendix shows no consistent symptom complex. The possible significance is discussed. ImagesFig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 1 PMID:5548558

  13. Effects of orally vs. parenterally administrated trimebutine on gastrointestinal and colonic motility in dogs.

    PubMed

    Buéno, L; Hondé, C; Pascaud, X; Junien, J L

    1987-01-01

    The influence of oral administration and intravenous infusion of trimebutine maleate (TMB) and N-desmethyl TMB (NDTMB), its main metabolite, was investigated in conscious dogs equipped with chronically implanted strain-gauges. In fasted dogs, TMB (10 to 20 mg/kg per os) delayed the occurrence of the next activity front on both stomach and duodenum by reinforcing the duration of the intestinal phase II. It also induced the occurrence of an additional migrating phase III. These effects were associated with a colonic stimulation generally followed by an inhibition. Comparatively NDTMB at similar dosages disrupted the antral cyclic phases which were replaced by continuous low amplitude contractions during 5-7 h. The MMC pattern persisted with a significant increase in the duration of phase II, and the colonic motility was inhibited during 4.3 to 6.7 h. Infused intravenously at a dose of 3 mg X kg-1 X h-1, TMB immediately inhibited the gastric cyclic contractions in fasted dogs. As for the oral route, the small bowel exhibited an increase in the duration of phase II frequently associated with the occurrence of an additional phase III. Furthermore an inhibition of the colonic motility was observed only at the end of the infusion and lasted at least 4 h. At similar dosage NDTMB had less pronounced inhibitory effects on gastric activity fronts and in contrast with TMB, the inhibitory effect on the colonic motility was observed as soon as the infusion of NDTMB started. These data demonstrate that orally administered TMB stimulates intestinal motility as previously described for i.v. route but in contrast to parenteral administration also stimulates antral and colonic motility.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3609630

  14. Non-invasive panel tests for gastrointestinal motility monitoring within the MARS-500 Project

    PubMed Central

    Roda, Aldo; Mirasoli, Mara; Guardigli, Massimo; Simoni, Patrizia; Festi, Davide; Afonin, Boris; Vasilyeva, Galina

    2013-01-01

    the H2-breath test was strongly affected by external factors, which may have been related to the diet of the crewmembers or to environmental conditions (e.g., the accumulation of hydrogen in the simulator microenvironment). At least in closed microenvironments such as the MARS-500 simulator, 13C-breath tests should therefore be preferred to H2-breath tests. Finally, the fecal calprotectin test showed significant alterations during the mission simulation: all of the crewmembers were negative for the test at the beginning of the simulation but showed various degrees of positivity in at least one of the subsequent tests, thus indicating the onset of an intestinal inflammation. CONCLUSION: Breath tests, especially those 13C-based, proved suitable for monitoring gastrointestinal motility in the 520-d isolation experiment within MARS-500 project and can be applied in long-term spaceflights. PMID:23599647

  15. Small intestinal ischemia and infarction

    MedlinePlus

    ... small intestine; Atherosclerosis - small intestine; Hardening of the arteries - small intestine ... Embolus: Blood clots can block one of the arteries supplying the intestine. People who have had a ...

  16. Regulation of flagellar motility during biofilm formation

    PubMed Central

    Guttenplan, Sarah B.; Kearns, Daniel B.

    2013-01-01

    Many bacteria swim in liquid or swarm over solid surfaces by synthesizing rotary flagella. The same bacteria that are motile also commonly form non-motile multicellular aggregates held together by an extracellular matrix called biofilms. Biofilms are an important part of the lifestyle of pathogenic bacteria and it is assumed that there is a motility-to-biofilm transition wherein the inhibition of motility promotes biofilm formation. The transition is largely inferred from regulatory mutants that reveal the opposite regulation of the two phenotypes. Here we review the regulation of motility during biofilm formation in Bacillus, Pseudomonas, Vibrio, and Escherichia, and we conclude that the motility-to-biofilm transition, if necessary, likely involves two steps. In the short term, flagella are functionally regulated to either inhibit rotation or modulate the basal flagellar reversal frequency. Over the long term, flagellar gene transcription is inhibited and in the absence of de novo synthesis, flagella are likely diluted to extinction through growth. Both short term and long term control is likely important to the motility-to-biofilm transition to stabilize aggregates and optimize resource investment. We emphasize the newly discovered classes of flagellar functional regulators and speculate that others await discovery in the context of biofilm formation. PMID:23480406

  17. Protonmotive force and motility of Bacillus subtilis.

    PubMed Central

    Shioi, J I; Imae, Y; Oosawa, F

    1978-01-01

    Motility of Bacillus subtilis was inhibited within a few minutes by a combination of valinomycin and a high concentration of potassium ions in the medium at neutral pH. Motility was restored by lowering the concentration of valinomycin or potassium ions. The valinomycin concentration necessary for motility inhibition was determined at various concentrations of potassium ions and various pH's. At pH 7.5, valinomycin of any concentration did not inhibit the motility, when the potassium ion concentration was lower than 9 mM. In the presence of 230 mM potassium ion, the motility inhibition by valinomycin was not detected at pH lower than 6.1. These results are easily explained by the idea that the motility of B. subtilis is supported by the electrochemical potential difference of the proton across the membrane, or the protonmotive force. The electrochemical potential difference necessary for motility was estimated to be about -90 mV. PMID:25261

  18. Complementary effects of propranolol and nonoxynol-9 upon human sperm motility.

    PubMed

    White, D R; Clarkson, J S; Ratnasooriya, W D; Aitken, R J

    1995-10-01

    The inhibitory effects of nonoxynol-9, DL- and D-propranolol upon human sperm motility were determined in vitro. All three compounds were capable of causing complete cessation of sperm movement. However, greater efficacy was achieved using combinations of nonoxynol-9 and propranolol, suggesting a complementary interaction between these compounds. Investigations of the mechanism of action of propranolol revealed that an influx of calcium accompanied the loss of motility. However, since incubation in the absence of calcium enhanced the spermicidal effects of this compound, it was concluded that this calcium influx did not constitute the primary means by which motility was disrupted. Low doses of propranolol, which did not affect motility, were found to inhibit the capacity of human spermatozoa for sperm-oocyte fusion. PMID:8605783

  19. Gastrointestinal symptoms and motility disorders in patients with systemic scleroderma

    PubMed Central

    Di Ciaula, Agostino; Covelli, Michele; Berardino, Massimo; Wang, David QH; Lapadula, Giovanni; Palasciano, Giuseppe; Portincasa, Piero

    2008-01-01

    Background Studies on gastrointestinal symptoms, dysfunctions, and neurological disorders in systemic scleroderma are lacking so far. Methods Thirty-eight scleroderma patients (34 limited, 4 diffuse), 60 healthy controls and 68 dyspeptic controls were scored for upper and lower gastrointestinal symptoms (dyspepsia, bowel habits), gastric and gallbladder emptying to liquid meal (functional ultrasonography) and small bowel transit (H2-breath test). Autonomic nerve function was assessed by cardiovascular tests. Results The score for dyspepsia (mainly gastric fullness) was greater in scleroderma patients than healthy controls, but lower than dyspeptic controls who had multiple symptoms, instead. Scleroderma patients with dyspepsia had a longer disease duration. Fasting antral area and postprandial antral dilatation were smaller in scleroderma patients than dyspeptic and healthy controls. Gastric emptying was delayed in both scleroderma patients (particularly in those with abnormal dyspeptic score) and dyspeptic controls, who also showed a larger residual area. Despite gallbladder fasting and postprandial volumes were comparable across the three groups, gallbladder refilling appeared delayed in dyspeptic controls and mainly dependent on delayed gastric emptying in scleroderma. Small intestinal transit was also delayed in 74% of scleroderma and 66% of dyspeptic controls. Bowel habits were similar among the three groups. Autonomic neuropathy was not associated with dyspepsia, gastric and gallbladder motility and small intestinal transit. Conclusion In scleroderma patients dyspepsia (mainly gastric fullness), restricted distension of the gastric antrum and diffuse gastrointestinal dysmotility are frequent features. These defects are independent from the occurrence of autonomic neuropathy. PMID:18304354

  20. Electrophoretic control of actomyosin motility

    NASA Astrophysics Data System (ADS)

    Hanson, Kristi L.; Solana, Gerardin; Nicolau, Dan V.

    2005-03-01

    The effect of DC electric field strength on in vitro actomyosin motility was examined. Rabbit skeletal muscle heavy meromyosin (HMM) was adsorbed to nitrocellulose-coated glass, and the myosin driven movement of fluorescently labeled actin filaments was recorded in the presence of 0 to 9000 V m-1 applied DC voltage. The applied electric field resulted in increased filament velocity and oriented actin movement, with leading heads of filaments directed towards the positive electrode. Velocity (v) was found to increase moderately with electric field strength at applied fields up to ~ 4500 V m-1 (Δv/ΔE = 0.037 μm2 V-1sec-1), and then increased at a more rapid rate (Δv/ΔE = 0.100 μm2 V-1sec-1) at higher field strengths up to 9000 V m-1. The electrophoretic effect caused up to 70% of actin motion to be oriented within 30 degrees of the positive electrode, with the largest effect observed using an applied field of 6000 V m-1. Higher electric field strengths caused filament breakage.

  1. Regulation of Eukaryotic Flagellar Motility

    NASA Astrophysics Data System (ADS)

    Mitchell, David R.

    2005-03-01

    The central apparatus is essential for normal eukaryotic flagellar bend propagation as evidenced by the paralysis associated with mutations that prevent central pair (CP) assembly. Interactions between doublet-associated radial spokes and CP projections are thought to modulate spoke-regulated protein kinases and phosphatases on outer doublets, and these enzymes in turn modulate dynein activity. To better understand CP control mechanisms, we determined the three-dimensional structure of the Chlamydomonas reinhardtii CP complex and analyzed CP orientation during formation and propagation of flagellar bending waves. We show that a single CP microtubule, C1, is near the outermost doublet in curved regions of the flagellum, and this orientation is maintained by twists between successive principal and reverse bends. The Chlamydomonas CP is inherently twisted; twists are not induced by bend formation, and do not depend on forces or signals transmitted through spoke-central pair interactions. We hypothesize that CP orientation passively responds to bend formation, and that bend propagation drives rotation of the CP and maintains a constant CP orientation in bends, which in turn permits signal transduction between specific CP projections and specific doublet-associated dyneins through radial spokes. The central pair kinesin, Klp1, although essential for normal motility, is therefore not the motor that drives CP rotation. The CP also acts as a scaffold for enzymes that maintain normal intraflagellar ATP concentration.

  2. Aspirin-induced increase in intestinal paracellular permeability does not affect the levels of LPS in venous blood of healthy women.

    PubMed

    Gnauck, Anne; Lentle, Roger G; Kruger, Marlena C

    2015-07-01

    The presence of subclinical levels of LPS from Gram-negative bacteria, also referred to as endotoxin, in the circulation may induce a pro-inflammatory immune response that leads to the development of obesity and insulin resistance. Recent data indicate that high-fat meals may elevate circulating levels of LPS. However, it is currently unclear how the LPS transits from the gut lumen to the general circulation. We determined whether aspirin-induced damage of the small intestinal mucosa, evidenced by an increase in the paracellular permeability, allows greater transit of LPS into the systemic circulation. The 3-h cumulative excretion of lactulose was significantly increased after the consumption of aspirin solution relative to that after the consumption of an equal volume of water in 15 healthy women (median after aspirin 0.09% of dose vs. median after water 0.03% of dose; P = 0.004). Dosage with aspirin also significantly increased the lactulose : mannitol ratio (median after aspirin 0.014 vs. median after water 0.005; P = 0.017). However, serum LPS levels after the consumption of the aspirin solution were not significantly different from those after consumption of the control (plain water). Further, there was no correlation between body fat content and circulating levels of LPS.

  3. A Novel Inducer of Roseobacter Motility Is Also a Disruptor of Algal Symbiosis

    PubMed Central

    Sule, Preeti

    2013-01-01

    Silicibacter sp. strain TM1040, a member of the Roseobacter clade, forms a symbiosis with unicellular phytoplankton, which is inextricably linked to the biphasic “swim or stick” lifestyle of the bacteria. Mutations in flaC bias the population toward the motile phase. Renewed examination of the FlaC− strain (HG1016) uncovered that it is composed of two different cells: a pigmented type, PS01, and a nonpigmented cell, PS02, each of which has an identical mutation in flaC. While monocultures of PS01 and PS02 had few motile cells (0.6 and 6%, respectively), coculturing the two strains resulted in a 10-fold increase in the number of motile cells. Cell-free supernatants from coculture or wild-type cells were fully capable of restoring motility to PS01 and PS02, which was due to increased fliC3 (flagellin) transcription, FliC3 protein levels per cell, and flagella synthesis. The motility-inducing compound has an estimated mass of 226 Da, as determined by mass spectrometry, and is referred to as Roseobacter Motility Inducer (RMI). Mutations affecting genes involved in phenyl acetic acid synthesis significantly reduced RMI, while defects in tropodithietic acid (TDA) synthesis had marginal or no effect on RMI. RMI biosynthesis is induced by p-coumaric acid, a product of algal lignin degradation. When added to algal cultures, RMI caused loss of motility, cell enlargement, and vacuolization in the algal cells. RMI is a new member of the roseobacticide family of troponoid compounds whose activities affect roseobacters, by shifting their population toward motility, as well as their phytoplankton hosts, through an algicidal effect. PMID:23161030

  4. Motility of liquid stored ram spermatozoa is altered by dilution rate independent of seminal plasma concentration.

    PubMed

    Mata-Campuzano, M; Soleilhavoup, C; Tsikis, G; Martinez-Pastor, F; de Graaf, S P; Druart, X

    2015-11-01

    The fertility after use of liquid stored ram semen following cervical AI rapidly decreases if semen is stored beyond 12h. The dilution of seminal plasma is often cited as a key contributor to the diminished motility and fertility of ram spermatozoa subjected to liquid preservation. Two experiments were conducted to assess the effect of spermatozoa concentration (i.e. dilution rate) and percentage of seminal plasma on the motility and viability of liquid stored ram spermatozoa. In Experiment 1, semen was diluted to one of seven concentrations ranging from 0.2 to 1.4×10(9)spermatozoa/ml with milk and assessed for motility after 3 or 24h of storage at 15°C. In Experiment 2, semen was collected and washed to remove seminal plasma before re-dilution to 0.2-1.4×10(9)spermatozoa/ml with milk containing 0%, 20% or 40% (final v/v ratio) seminal plasma and assessed for viability and motility after 3 or 24h of storage at 15°C. Whereas motility was not affected by spermatozoa concentration after 3h of storage, the proportion of progressive spermatozoa decreased after 24h of storage when spermatozoa concentration was greater than 1.0×10(9)spermatozoa/ml. The duration of preservation and the spermatozoa concentration affected spermatozoa motility but had no impact on spermatozoa viability. This negative effect of greater spermatozoa concentrations on motility was independent of the presence and the concentration of seminal plasma. The seminal plasma at both concentrations (20% and 40%) had a protective effect on spermatozoa motility after 24h of storage. These findings have the potential to improve the efficiency of cervical AI with liquid stored ram semen.

  5. Motility in the epsilon-proteobacteria.

    PubMed

    Beeby, Morgan

    2015-12-01

    The epsilon-proteobacteria are a widespread group of flagellated bacteria frequently associated with either animal digestive tracts or hydrothermal vents, with well-studied examples in the human pathogens of Helicobacter and Campylobacter genera. Flagellated motility is important to both pathogens and hydrothermal vent members, and a number of curious differences between the epsilon-proteobacterial and enteric bacterial motility paradigms make them worthy of further study. The epsilon-proteobacteria have evolved to swim at high speed and through viscous media that immobilize enterics, a phenotype that may be accounted for by the molecular architecture of the unusually large epsilon-proteobacterial flagellar motor. This review summarizes what is known about epsilon-proteobacterial motility and focuses on a number of recent discoveries that rationalize the differences with enteric flagellar motility. PMID:26590774

  6. Mammalian Sperm Motility: Observation and Theory

    NASA Astrophysics Data System (ADS)

    Gaffney, E. A.; Gadêlha, H.; Smith, D. J.; Blake, J. R.; Kirkman-Brown, J. C.

    2011-01-01

    Mammalian spermatozoa motility is a subject of growing importance because of rising human infertility and the possibility of improving animal breeding. We highlight opportunities for fluid and continuum dynamics to provide novel insights concerning the mechanics of these specialized cells, especially during their remarkable journey to the egg. The biological structure of the motile sperm appendage, the flagellum, is described and placed in the context of the mechanics underlying the migration of mammalian sperm through the numerous environments of the female reproductive tract. This process demands certain specific changes to flagellar movement and motility for which further mechanical insight would be valuable, although this requires improved modeling capabilities, particularly to increase our understanding of sperm progression in vivo. We summarize current theoretical studies, highlighting the synergistic combination of imaging and theory in exploring sperm motility, and discuss the challenges for future observational and theoretical studies in understanding the underlying mechanics.

  7. How substrate rigidity regulates the cellular motility

    NASA Astrophysics Data System (ADS)

    Sarvestani, Alireza

    2011-03-01

    Mechanical stiffness of bio-adhesive substrates has been recognized as a major regulator of cell motility. We present a simple physical model to study the crawling locomotion of a contractile cell on a soft elastic substrate. The mechanism of rigidity sensing is accounted for using Schwarz's two spring model (Schwarz et al. (2006) BioSystems 83, 225-232). The predicted dependency between the speed of motility and substrate stiffness is qualitatively consistent with experimental observations. The model demonstrates that the rigidity dependent motility of cells is rooted in the regulation of actomyosin contractile forces by substrate deformation at each anchorage point. On stiffer substrates, the traction forces required for cell translocation acquire larger magnitude but show weaker asymmetry which leads to slower cell motility. On very soft substrates, the model predicts a biphasic relationship between the substrate rigidity and the speed of locomotion, over a narrow stiffness range, which has been observed experimentally for some cell types.

  8. Implications of altered gastrointestinal motility in obesity.

    PubMed

    Gallagher, T K; Geoghegan, J G; Baird, A W; Winter, D C

    2007-10-01

    The onset of obesity occurs as a result of an imbalance between nutrient consumption/absorption and energy expenditure. Gastrointestinal (GI) motility plays a critical role in the rate of consumption of foods, digestion, and absorption of nutrients. Various segments of the GI tract coordinate in a complex yet precise way, to control the process of food consumption, digestion, and absorption of nutrients. GI motility not only regulates the rates at which nutrients are processed and absorbed in the gut, but also, via mechanical and neurohormonal methods, participates in the control of appetite and satiety. Altered GI motility has frequently been observed in obese patients, the significance of which is incompletely understood. However, these alterations can be considered as potential contributing factors in the development and maintenance of obesity and changed eating behavior. Therapies aimed at regulating or counteracting the observed changes in GI motility are being actively explored and applied clinically in the management of obese patients. PMID:18098402

  9. The mesenterially perfused rat small intestine: A versatile approach for pharmacological testings.

    PubMed

    Schreiber, Dominik; Klotz, Markus; Laures, Kerstin; Clasohm, Jasmin; Bischof, Michael; Schäfer, Karl-Herbert

    2014-05-01

    Pharmaceutical compounds enter the body via several major natural gateways; i.e. the lung, the skin and the gastrointestinal tract. Drug application during surgical operations can lead to severe impairment of gastrointestinal motility, which can contribute to a paralytic ileus. Here we investigated an ex vivo perfused small intestine model that allows us to ascertain the influence of pharmaceuticals upon the gut. Corresponding segments from the proximal jejunum of adult rats were used. Their mesenteric arteries and veins were cannulated and the jejunal segment excised. The individual segments were placed in a custom designed perfusion chamber and perfusion performed through the intestinal lumen as well as the mesenteric superior artery. Three test drugs, which are commonly used in anesthesiology; i.e. pentobarbital, propofol and ketamine were administered via the blood vessels. Their effects upon gastrointestinal motility patterns were evaluated by optical measurements. Longitudinal and pendular movements were distinguishable and separately analyzed. Pharmacological effects of the individual substances could be investigated. Propofol (50-200 μg/ml) was found to decrease intestinal motility, especially longitudinal movements in a dose dependent manner. Pentobarbital decreased intestinal motility only at high concentrations, above 2.5 mg/ml. A dose of 2.5 mg/ml lead to an increase in longitudinal- and pendular movements in comparison to control, while ketamine (2.5-10 mg/ml) did not alter intestinal motility at all. Histological examination of the perfused segments revealed only minor changes in tissue morphology after perfusion. The perfusion approach shown here allows for the identification of compounds which interfere with gut motility in a highly sophisticated way. It is suitable for characterization of drug and dose specific changes in motility patterns and can be used in drug development and preclinical studies.

  10. ATPases, ion exchangers and human sperm motility.

    PubMed

    Peralta-Arias, Rubén D; Vívenes, Carmen Y; Camejo, María I; Piñero, Sandy; Proverbio, Teresa; Martínez, Elizabeth; Marín, Reinaldo; Proverbio, Fulgencio

    2015-05-01

    Human sperm has several mechanisms to control its ionic milieu, such as the Na,K-ATPase (NKA), the Ca-ATPase of the plasma membrane (PMCA), the Na(+)/Ca(2) (+)-exchanger (NCX) and the Na(+)/H(+)-exchanger (NHE). On the other hand, the dynein-ATPase is the intracellular motor for sperm motility. In this work, we evaluated NKA, PMCA, NHE, NCX and dynein-ATPase activities in human sperm and investigated their correlation with sperm motility. Sperm motility was measured by Computer Assisted Semen Analysis. It was found that the NKA activity is inhibited by ouabain with two Ki (7.9 × 10(-9) and 9.8 × 10(-5) M), which is consistent with the presence of two isoforms of α subunit of the NKA in the sperm plasma membranes (α1 and α4), being α4 more sensitive to ouabain. The decrease in NKA activity is associated with a reduction in sperm motility. In addition, sperm motility was evaluated in the presence of known inhibitors of NHE, PMCA and NCX, such as amiloride, eosin, and KB-R7943, respectively, as well as in the presence of nigericin after incubation with ouabain. Amiloride, eosin and KB-R7943 significantly reduced sperm motility. Nigericin reversed the effect of ouabain and amiloride on sperm motility. Dynein-ATPase activity was inhibited by acidic pH and micromolar concentrations of Ca(2) (+). We explain our results in terms of inhibition of the dynein-ATPase in the presence of higher cytosolic H(+) and Ca(2) (+), and therefore inhibition of sperm motility. PMID:25820902

  11. Novel mechanisms power bacterial gliding motility.

    PubMed

    Nan, Beiyan; Zusman, David R

    2016-07-01

    For many bacteria, motility is essential for survival, growth, virulence, biofilm formation and intra/interspecies interactions. Since natural environments differ, bacteria have evolved remarkable motility systems to adapt, including swimming in aqueous media, and swarming, twitching and gliding on solid and semi-solid surfaces. Although tremendous advances have been achieved in understanding swimming and swarming motilities powered by flagella, and twitching motility powered by Type IV pili, little is known about gliding motility. Bacterial gliders are a heterogeneous group containing diverse bacteria that utilize surface motilities that do not depend on traditional flagella or pili, but are powered by mechanisms that are less well understood. Recently, advances in our understanding of the molecular machineries for several gliding bacteria revealed the roles of modified ion channels, secretion systems and unique machinery for surface movements. These novel mechanisms provide rich source materials for studying the function and evolution of complex microbial nanomachines. In this review, we summarize recent findings made on the gliding mechanisms of the myxobacteria, flavobacteria and mycoplasmas. PMID:27028358

  12. Flagellar motility in eukaryotic human parasites.

    PubMed

    Krüger, Timothy; Engstler, Markus

    2015-10-01

    A huge variety of protists rely on one or more motile flagella to either move themselves or move fluids and substances around them. Many of these flagellates have evolved a symbiotic or parasitic lifestyle. Several of the parasites have adapted to human hosts, and include agents of prevalent and serious diseases. These unicellular parasites have become specialised in colonising a wide range of biological niches within humans. They usually have diverse transmission cycles, and frequently manifest a variety of distinct morphological stages. The motility of the single or multiple flagella plays important but understudied roles in parasite transmission, host invasion, dispersal, survival, proliferation and pathology. In this review we provide an overview of the important human pathogens that possess a motile flagellum for at least part of their life cycle. We highlight recently published studies that aim to elucidate motility mechanisms, and their relevance for human disease. We then bring the physics of swimming at the microscale into context, emphasising the importance of interdisciplinary approaches for a full understanding of flagellate motility - especially in light of the parasites' microenvironments and population dynamics. Finally, we summarise some important technological aspects, describing challenges for the field and possibilities for motility analyses in the future.

  13. Flagellar motility in eukaryotic human parasites.

    PubMed

    Krüger, Timothy; Engstler, Markus

    2015-10-01

    A huge variety of protists rely on one or more motile flagella to either move themselves or move fluids and substances around them. Many of these flagellates have evolved a symbiotic or parasitic lifestyle. Several of the parasites have adapted to human hosts, and include agents of prevalent and serious diseases. These unicellular parasites have become specialised in colonising a wide range of biological niches within humans. They usually have diverse transmission cycles, and frequently manifest a variety of distinct morphological stages. The motility of the single or multiple flagella plays important but understudied roles in parasite transmission, host invasion, dispersal, survival, proliferation and pathology. In this review we provide an overview of the important human pathogens that possess a motile flagellum for at least part of their life cycle. We highlight recently published studies that aim to elucidate motility mechanisms, and their relevance for human disease. We then bring the physics of swimming at the microscale into context, emphasising the importance of interdisciplinary approaches for a full understanding of flagellate motility - especially in light of the parasites' microenvironments and population dynamics. Finally, we summarise some important technological aspects, describing challenges for the field and possibilities for motility analyses in the future. PMID:26523344

  14. Dietary folate does not significantly affect the intestinal microbiome, inflammation or tumorigenesis in azoxymethane-dextran sodium sulphate-treated mice.

    PubMed

    MacFarlane, Amanda J; Behan, Nathalie A; Matias, Fernando M G; Green, Judy; Caldwell, Don; Brooks, Stephen P J

    2013-02-28

    Inflammatory bowel disease (IBD) is a risk factor for the development of colon cancer. Environmental factors including diet and the microflora influence disease outcome. Folate and homocysteine have been associated with IBD-mediated colon cancer but their roles remain unclear. We used a model of chemically induced ulcerative colitis (dextran sodium sulphate (DSS)) with or without the colon carcinogen azoxymethane (AOM) to determine the impact of dietary folic acid (FA) on colonic microflora and the development of colon tumours. Male mice (n 15 per group) were fed a FA-deficient (0 mg/kg), control (2 mg/kg) or FA-supplemented (8 mg/kg) diet for 12 weeks. Folate status was dependent on the diet (P< 0·001) and colitis-induced treatment (P= 0·04) such that mice with colitis had lower circulating folate. FA had a minimal effect on tumour initiation, growth and progression, although FA-containing diets tended to be associated with a higher tumour prevalence in DSS-treated mice (7-20 v. 0%, P= 0·08) and the development of more tumours in the distal colon of AOM-treated mice (13-83% increase, P= 0·09). Folate deficiency was associated with hyperhomocysteinaemia (P< 0·001) but homocysteine negatively correlated with tumour number (r - 0·58, P= 0·02) and load (r - 0·57, P= 0·02). FA had no effect on the intestinal microflora. The present data indicate that FA intake has no or little effect on IBD or IBD-mediated colon cancer in this model and that hyperhomocysteinaemia is a biomarker of dietary status and malabsorption rather than a cause of IBD-mediated colon cancer. PMID:23021249

  15. Fluoroscopic study of the normal gastrointestinal motility and measurements in the Hispaniolan Amazon parrot (Amazona ventralis).

    PubMed

    Beaufrère, Hugues; Nevarez, Javier; Taylor, W Michael; Jankowski, Gwendolyn; Rademacher, Nathalie; Gaschen, Lorrie; Pariaut, Romain; Tully, Thomas N

    2010-01-01

    Contrast fluoroscopy is a valuable tool to examine avian gastrointestinal motility. However, the lack of a standardized examination protocol and reference ranges prevents the objective interpretation of motility disorders and other gastrointestinal abnormalities. Our goals were to evaluate gastrointestinal motility in 20 Hispaniolan Amazon parrots (Amazona ventralis) by contrast fluoroscopy. Each parrot was crop-fed an equal part mixture of barium sulfate and hand-feeding formula and placed in a cardboard box for fluoroscopy. Over a 3-h period, 1.5 minute segments of lateral and ventrodorsal fluoroscopy were recorded every 30 min. The gastric cycle and patterns of intestinal motility were described. The frequency of crop contractions, esophageal boluses, and gastric cycles were determined in lateral and ventrodorsal views. A range of 3.4-6.6 gastric cycles/min was noted on the lateral view and 3.0-6.6 gastric cycles/min on the ventrodorsal view. Circular measurements of the proventriculus diameter, ventriculus width, and length were obtained using the midshaft femoral diameter as a standard reference unit. The upper limits of the reference ranges were 3.6 and 4.7 femoral units for the proventriculus diameter in the lateral and ventrodorsal view, respectively. Two consecutive measurements were obtained and the measurement technique was found to have high reproducibility. In this study, we established a standardized protocol for contrast fluoroscopic examination of the gastrointestinal tract and a reliable measurement method of the proventriculus and ventriculus using femoral units in the Hispaniolan Amazon parrot.

  16. C-di-GMP Regulates Motile to Sessile Transition by Modulating MshA Pili Biogenesis and Near-Surface Motility Behavior in Vibrio cholerae.

    PubMed

    Jones, Christopher J; Utada, Andrew; Davis, Kimberly R; Thongsomboon, Wiriya; Zamorano Sanchez, David; Banakar, Vinita; Cegelski, Lynette; Wong, Gerard C L; Yildiz, Fitnat H

    2015-10-01

    In many bacteria, including Vibrio cholerae, cyclic dimeric guanosine monophosphate (c-di-GMP) controls the motile to biofilm life style switch. Yet, little is known about how this occurs. In this study, we report that changes in c-di-GMP concentration impact the biosynthesis of the MshA pili, resulting in altered motility and biofilm phenotypes in V. cholerae. Previously, we reported that cdgJ encodes a c-di-GMP phosphodiesterase and a ΔcdgJ mutant has reduced motility and enhanced biofilm formation. Here we show that loss of the genes required for the mannose-sensitive hemagglutinin (MshA) pilus biogenesis restores motility in the ΔcdgJ mutant. Mutations of the predicted ATPase proteins mshE or pilT, responsible for polymerizing and depolymerizing MshA pili, impair near surface motility behavior and initial surface attachment dynamics. A ΔcdgJ mutant has enhanced surface attachment, while the ΔcdgJmshA mutant phenocopies the high motility and low attachment phenotypes observed in a ΔmshA strain. Elevated concentrations of c-di-GMP enhance surface MshA pilus production. MshE, but not PilT binds c-di-GMP directly, establishing a mechanism for c-di-GMP signaling input in MshA pilus production. Collectively, our results suggest that the dynamic nature of the MshA pilus established by the assembly and disassembly of pilin subunits is essential for transition from the motile to sessile lifestyle and that c-di-GMP affects MshA pilus assembly and function through direct interactions with the MshE ATPase.

  17. C-di-GMP Regulates Motile to Sessile Transition by Modulating MshA Pili Biogenesis and Near-Surface Motility Behavior in Vibrio cholerae

    PubMed Central

    Jones, Christopher J.; Utada, Andrew; Davis, Kimberly R.; Thongsomboon, Wiriya; Zamorano Sanchez, David; Banakar, Vinita; Cegelski, Lynette; Wong, Gerard C. L.; Yildiz, Fitnat H.

    2015-01-01

    In many bacteria, including Vibrio cholerae, cyclic dimeric guanosine monophosphate (c-di-GMP) controls the motile to biofilm life style switch. Yet, little is known about how this occurs. In this study, we report that changes in c-di-GMP concentration impact the biosynthesis of the MshA pili, resulting in altered motility and biofilm phenotypes in V. cholerae. Previously, we reported that cdgJ encodes a c-di-GMP phosphodiesterase and a ΔcdgJ mutant has reduced motility and enhanced biofilm formation. Here we show that loss of the genes required for the mannose-sensitive hemagglutinin (MshA) pilus biogenesis restores motility in the ΔcdgJ mutant. Mutations of the predicted ATPase proteins mshE or pilT, responsible for polymerizing and depolymerizing MshA pili, impair near surface motility behavior and initial surface attachment dynamics. A ΔcdgJ mutant has enhanced surface attachment, while the ΔcdgJmshA mutant phenocopies the high motility and low attachment phenotypes observed in a ΔmshA strain. Elevated concentrations of c-di-GMP enhance surface MshA pilus production. MshE, but not PilT binds c-di-GMP directly, establishing a mechanism for c-di-GMP signaling input in MshA pilus production. Collectively, our results suggest that the dynamic nature of the MshA pilus established by the assembly and disassembly of pilin subunits is essential for transition from the motile to sessile lifestyle and that c-di-GMP affects MshA pilus assembly and function through direct interactions with the MshE ATPase. PMID:26505896

  18. Intestinal bacteria and ageing.

    PubMed

    Woodmansey, E J

    2007-05-01

    Advancements in science and medicine, as well as improved living standards, have led to a steady increase in life expectancy, and subsequently a rise in the elderly population. The intestinal microbiota is important for maintenance of host health, providing energy, nutrients and protection against invading organisms. Although the colonic microbiota is relatively stable throughout adult life, age-related changes in the gastrointestinal (GI) tract, as well as changes in diet and host immune system reactivity, inevitably affect population composition. Recent studies indicate shifts in the composition of the intestinal microbiota, which may lead to detrimental effects for the elderly host. Increased numbers of facultative anaerobes, in conjunction with a decrease in beneficial organisms such as the anaerobic lactobacilli and bifidobacteria, amongst other anaerobes, have been reported. These changes, along with a general reduction in species diversity in most bacterial groups, and changes to diet and digestive physiology such as intestinal transit time, may result in increased putrefaction in the colon and a greater susceptibility to disease. Therapeutic strategies to counteract these changes have been suggested in ageing people. These include dietary supplements containing prebiotics, probiotics and a combination of both of these, synbiotics. Limited feeding trials show promising results with these supplements, although further longer-term investigations are required to substantiate their use in elderly healthcare fields. PMID:17448153

  19. Targeting motility properties of bacteria in the development of probiotic cultures against Campylobacter jejuni in broiler chickens.

    PubMed

    Aguiar, Vivian F; Donoghue, Ann M; Arsi, Komala; Reyes-Herrera, Ixchel; Metcalf, Joel H; de los Santos, Fausto S; Blore, Pamela J; Donoghue, Dan J

    2013-05-01

    Campylobacter is the leading cause of gastroenteritis worldwide. Campylobacter is commonly present in the intestinal tract of poultry, and one strategy to reduce enteric colonization is the use of probiotic cultures. This strategy has successfully reduced enteric colonization of Salmonella, but has had limited success against Campylobacter. In an effort to improve the efficacy of probiotic cultures, we developed a novel in vitro screening technique for selecting bacterial isolates with enhanced motility. It is proposed that motility-selected bacteria have the marked ability to reach the same gastrointestinal niche in poultry and competitively reduce C. jejuni. Bacterial isolates were collected from ceca of healthy chickens, and motile isolates were identified and tested for anti-Campylobacter activity. Isolates with these properties were selected for increased motility by passing each isolate 10 times and at each passage selecting bacteria that migrated the farthest during each passage. Three bacterial isolates with the greatest motility (all Bacillus subtilis) were used alone or in combination in two chicken trials. At day of hatch, chicks were administered these isolates alone or in combination (n=10/treatment, two trials), and chicks were orally challenged with a mixture of four different wild-type strains of C. jejuni (∼10(5) CFU/mL) on day 7. Isolate 1 reduced C. jejuni colonization in both of the trials (p<0.05). A follow-up study was conducted to compare isolate 1 subjected to enhanced motility selection with its nonselected form. A reduction (p<0.05) in Campylobacter colonization was observed in all three trials in the chickens dosed using isolate with enhanced motility compared to the control and unselected isolate. These findings support the theory that the motility enhancement of potential probiotic bacteria may provide a strategy for reduction of C. jejuni in preharvest chickens.

  20. Dietary protein level and source differentially affect bone metabolism, strength, and intestinal calcium transporter expression during ad libitum and food-restricted conditions in male rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    High protein diets may attenuate bone loss during energy restriction (ER). The objective of the current study was to determine whether high protein diets suppress bone turnover and improve bone quality in rats during ER and whether dietary protein source affects this relationship. Eighty 12-week o...

  1. Identification of quantitative trait loci affecting resistance to gastro-intestinal parasites in a double backcross population of Red Maasai and Dorper sheep

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A genome-wide scan for quantitative trait loci (QTL) affecting gastrointestinal (GI) nematode resistance was completed using a double backcross sheep population derived from Red Maasai and Dorper ewes bred to F1 rams. These breeds were chosen, because Red Maasai sheep are known to be more tolerant ...

  2. HEATR2 Plays a Conserved Role in Assembly of the Ciliary Motile Apparatus

    PubMed Central

    zur Lage, Petra; Ait-Lounis, Aouatef; Schmidts, Miriam; Shoemark, Amelia; Garcia Munoz, Amaya; Halachev, Mihail R.; Gautier, Philippe; Yeyati, Patricia L.; Bonthron, David T.; Carr, Ian M.; Hayward, Bruce; Markham, Alexander F.; Hope, Jilly E.; von Kriegsheim, Alex; Mitchison, Hannah M.; Jackson, Ian J.; Durand, Bénédicte; Reith, Walter; Sheridan, Eamonn; Jarman, Andrew P.; Mill, Pleasantine

    2014-01-01

    Cilia are highly conserved microtubule-based structures that perform a variety of sensory and motility functions during development and adult homeostasis. In humans, defects specifically affecting motile cilia lead to chronic airway infections, infertility and laterality defects in the genetically heterogeneous disorder Primary Ciliary Dyskinesia (PCD). Using the comparatively simple Drosophila system, in which mechanosensory neurons possess modified motile cilia, we employed a recently elucidated cilia transcriptional RFX-FOX code to identify novel PCD candidate genes. Here, we report characterization of CG31320/HEATR2, which plays a conserved critical role in forming the axonemal dynein arms required for ciliary motility in both flies and humans. Inner and outer arm dyneins are absent from axonemes of CG31320 mutant flies and from PCD individuals with a novel splice-acceptor HEATR2 mutation. Functional conservation of closely arranged RFX-FOX binding sites upstream of HEATR2 orthologues may drive higher cytoplasmic expression of HEATR2 during early motile ciliogenesis. Immunoprecipitation reveals HEATR2 interacts with DNAI2, but not HSP70 or HSP90, distinguishing it from the client/chaperone functions described for other cytoplasmic proteins required for dynein arm assembly such as DNAAF1-4. These data implicate CG31320/HEATR2 in a growing intracellular pre-assembly and transport network that is necessary to deliver functional dynein machinery to the ciliary compartment for integration into the motile axoneme. PMID:25232951

  3. The relationship between gastrointestinal motility and gastric dilatation-volvulus in dogs.

    PubMed

    Gazzola, Krista M; Nelson, Laura L

    2014-09-01

    Gastric dilatation-volvulus (GDV) is a devastating disease that most commonly affects large and giant-breed dogs. Though a number of risk factors have been associated with the development of GDV, the etiology of GDV remains unclear. Abnormal gastric motility patterns and delayed gastric emptying have been previously described in dogs following GDV. Work evaluating the effects of gastropexy procedures and changes to gastric motility after experimental GDV has not found the same changes as those found in dogs with naturally occurring GDV. Although the role of abnormal gastric motility in dogs with GDV will need to be clarified with additional research, such study is likely to be facilitated by improved access to and development of noninvasive measurement techniques for the evaluation of gastric emptying and other motility parameters. In particular, the availability of Food and Drug Administration-approved wireless motility devices for the evaluation of gastrointestinal motility is particularly promising in the study of GDV and other functional gastrointestinal diseases of large and giant-breed dogs.

  4. A Nutrient-Tunable Bistable Switch Controls Motility in Salmonella enterica Serovar Typhimurium

    PubMed Central

    Koirala, Santosh; Mears, Patrick; Sim, Martin; Golding, Ido; Chemla, Yann R.; Aldridge, Phillip D.

    2014-01-01

    ABSTRACT Many bacteria are motile only when nutrients are scarce. In contrast, Salmonella enterica serovar Typhimurium is motile only when nutrients are plentiful, suggesting that this bacterium uses motility for purposes other than foraging, most likely for host colonization. In this study, we investigated how nutrients affect motility in S. enterica and found that they tune the fraction of motile cells. In particular, we observed coexisting populations of motile and nonmotile cells, with the distribution being determined by the concentration of nutrients in the growth medium. Interestingly, S. enterica responds not to a single nutrient but apparently to a complex mixture of them. Using a combination of experimentation and mathematical modeling, we investigated the mechanism governing this behavior and found that it results from two antagonizing regulatory proteins, FliZ and YdiV. We also found that a positive feedback loop involving the alternate sigma factor FliA is required, although its role appears solely to amplify FliZ expression. We further demonstrate that the response is bistable: that is, genetically identical cells can exhibit different phenotypes under identical growth conditions. Together, these results uncover a new facet of the regulation of the flagellar genes in S. enterica and further demonstrate how bacteria employ phenotypic diversity as a general mechanism for adapting to change in their environment. PMID:25161191

  5. Statistical physical models of cellular motility

    NASA Astrophysics Data System (ADS)

    Banigan, Edward J.

    Cellular motility is required for a wide range of biological behaviors and functions, and the topic poses a number of interesting physical questions. In this work, we construct and analyze models of various aspects of cellular motility using tools and ideas from statistical physics. We begin with a Brownian dynamics model for actin-polymerization-driven motility, which is responsible for cell crawling and "rocketing" motility of pathogens. Within this model, we explore the robustness of self-diffusiophoresis, which is a general mechanism of motility. Using this mechanism, an object such as a cell catalyzes a reaction that generates a steady-state concentration gradient that propels the object in a particular direction. We then apply these ideas to a model for depolymerization-driven motility during bacterial chromosome segregation. We find that depolymerization and protein-protein binding interactions alone are sufficient to robustly pull a chromosome, even against large loads. Next, we investigate how forces and kinetics interact during eukaryotic mitosis with a many-microtubule model. Microtubules exert forces on chromosomes, but since individual microtubules grow and shrink in a force-dependent way, these forces lead to bistable collective microtubule dynamics, which provides a mechanism for chromosome oscillations and microtubule-based tension sensing. Finally, we explore kinematic aspects of cell motility in the context of the immune system. We develop quantitative methods for analyzing cell migration statistics collected during imaging experiments. We find that during chronic infection in the brain, T cells run and pause stochastically, following the statistics of a generalized Levy walk. These statistics may contribute to immune function by mimicking an evolutionarily conserved efficient search strategy. Additionally, we find that naive T cells migrating in lymph nodes also obey non-Gaussian statistics. Altogether, our work demonstrates how physical

  6. Effects of traditional Chinese herbal medicine San-Huang-Xie-Xin-Tang on gastrointestinal motility in mice

    PubMed Central

    Hwang, Min Woo; Ahn, Tae Seok; Hong, Noo Ri; Jeong, Han-Sol; Jung, Myeong Ho; Ha, Ki-Tae; Kim, Byung Joo

    2015-01-01

    AIM: To investigate the effects of San-Huang-Xie-Xin-Tang (SHXXT), a herbal product used in traditional Chinese medicine, on gastrointestinal (GI) motility in mice. METHODS: The in vivo effects of SHXXT on GI motility were investigated by measuring the intestinal transit rates (ITRs) using Evans blue in normal mice and in mice with experimentally induced GI motility dysfunction (GMD). RESULTS: In normal ICR mice, ITRs were significantly and dose-dependently increased by SHXXT (0.1-1 g/kg). GMD was induced by injecting acetic acid or streptozotocin intraperitoneally. The ITRs of GMD mice were significantly reduced compared to normal mice, and these reductions were significantly and dose-dependently inhibited by SHXXT (0.1-1 g/kg). CONCLUSION: These results suggest that SHXXT is a novel candidate for the development of a prokinetic agent that may prevent or alleviate GMD. PMID:25632184

  7. Cellular Motility--Experiments on Contractile and Motile Mechanisms in the Slime Mould, Physarum Polycephalum

    ERIC Educational Resources Information Center

    Holmes, R. P.; Stewart, P. R.

    1977-01-01

    Actin and myosin have now been demonstrated to be important constituents of many eukaryotic cells. Their role is primarily that of a contractile system underlying all aspects of cellular motility. Described here is a simple experimental system to demonstrate quantitatively aspects of motility and its regulation in a slime mold. (Author/MA)

  8. Intestinal protozoa.

    PubMed

    Juckett, G

    1996-06-01

    Giardia is the best known cause of protozoal gastrointestinal disease in North America, producing significant but not life-threatening gastrointestinal distress and diarrhea. Although diagnosis of giardiasis may be challenging, treatment is usually successful. Entamoeba histolytica poses a rarer but far more difficult clinical challenge. Dysentery caused by E. histolytica may be the most feared intestinal protozoal infection, although Cryptosporidium parvum, Balantidium coli, Isospora belli, Sarcocystis species and other newly described protozoa also may cause diarrhea in healthy individuals and may result in intractable, life-threatening illness in patients with acquired immunodeficiency syndrome or other immunosuppressive diseases. Certain protozoa once considered relatively unimportant, such as Cryptosporidium, are now recognized as significant causes of morbidity even in the United States, since transmission readily occurs through contaminated water. PMID:8644565

  9. Motility modes of the parasite Trypanosoma brucei

    NASA Astrophysics Data System (ADS)

    Temel, Fatma Zeynep; Qu, Zijie; McAllaster, Michael; de Graffenried, Christopher; Breuer, Kenneth

    2015-11-01

    The parasitic single-celled protozoan Trypanosoma brucei causes African Sleeping Sickness, which is a fatal disease in humans and animals that threatens more than 60 million people in 36 African countries. Cell motility plays a critical role in the developmental phases and dissemination of the parasite. Unlike many other motile cells such as bacteria Escherichia coli or Caulobacter crescentus, the flagellum of T. brucei is attached along the length of its awl-like body, producing a unique mode of motility that is not fully understood or characterized. Here, we report on the motility of T. brucei, which swims using its single flagellum employing both rotating and undulating propulsion modes. We tracked cells in real-time in three dimensions using fluorescent microscopy. Data obtained from experiments using both short-term tracking within the field of view and long-term tracking using a tracking microscope were analyzed. Motility modes and swimming speed were analyzed as functions of cell size, rotation rate and undulation pattern. Research supported by NSF.

  10. Competency based medical education in gastrointestinal motility.

    PubMed

    Yadlapati, R; Keswani, R N; Pandolfino, J E

    2016-10-01

    Traditional apprenticeship-based medical education methods focusing on subjective evaluations and case-volume requirements do not reliably produce clinicians that provide high-quality care in unsupervised practice. Consequently, training approaches are shifting towards competency based medical education, which incorporates robust assessment methods and credible standards of physician proficiency. However, current gastroenterology and hepatology training in the US continues to utilize procedural volume and global impressions without standardized criteria as markers of competence. In particular, efforts to optimize competency based training in gastrointestinal (GI) motility are not underway, even though GI motility disorders account for nearly half of outpatient gastroenterology visits. These deficiencies compromise the quality of patient care. Thus, there is a great need and opportunity to shift our focus in GI motility training towards a competency based approach. First, we need to clarify the variable rates of learning for individual diagnostic tests. We must develop integrated systems that standardize training and monitor physician competency for GI motility diagnostics. Finally, as a profession and society, we must create certification processes to credential competent physicians. These advances are critical to optimizing the quality of GI motility diagnostics in practice.

  11. Effect of altered gastric emptying and gastrointestinal motility on metformin absorption

    PubMed Central

    Marathe, Punit H; Wen, Yandong; Norton, Jean; Greene, Douglas S; Barbhaiya, Rashmi H; Wilding, Ian R

    2000-01-01

    Aims The purpose of this in vivo human study was to assess the effect of altered gastric emptying and gastrointestinal motility on the absorption of metformin in healthy subjects. Methods An open-label, three treatment, three period crossover study was conducted in 11 healthy volunteers. Each subject received 550 mg metformin hydrochloride in solution alone; 5 min after a 10 mg i.v. dose of metoclopramide; and 30 min after a 30 mg oral dose of propantheline. Metformin solution was radiolabeled by the addition of 99mTc-DTPA. The gastrointestinal transit of the solution was monitored by gamma scintigraphy and the pharmacokinetic data were correlated with the scintigraphic findings. Results Scintigraphic data indicated that pretreatment with metoclopramide decreased gastric emptying time and increased gastrointestinal motility while pretreatment with propantheline had the opposite effect. The systemic disposition of metformin was not altered by pretreatment with metoclopramide and propantheline, as judged by unchanged renal clearance and elimination half-life of metformin. Extent of metformin absorption was essentially unchanged after pretreatment with metoclopramide. However, AUC(0,∞) and % UR (percent dose excreted unchanged in urine) generally increased with increase in gastric emptying time and small intestinal transit times. GI overlay plots showed that the absorption phase of metformin plasma profile always coincided with gastric emptying and the beginning of decline of metformin plasma concentrations was usually associated with the colon arrival. Only in cases where the intestinal transit was drastically prolonged by propantheline pretreatment, was a decline in plasma levels observed prior to colon arrival. Conclusions Metformin is primarily absorbed from the small intestine. The extent of metformin absorption is improved when the gastrointestinal motility is slowed. These findings have significant implications in the design of a metformin modified release

  12. Visual versus cinemicrographic evaluation of human sperm motility and morphology.

    PubMed

    Freund, M; Oliveira, N

    1987-01-01

    Ratings of human sperm motility by visual estimation through the microscope remain important measures of semen quality and of male fertility. More objective methods, including cinemicrography, time lapse photography, and videomicrography, are advocated. Subjective (visual) and objective (cinemicrographic) ratings of motility were compared. Sixty workers in 30 laboratories rated motilities of 40 specimens on motion picture film, and motilities were also measured by cinephotomicrographic methods. The morphology of each of the motile and immotile sperm was rated. In 34 of 40 specimens visual ratings were higher (range = +2 to +31%) than actual percentage motility. Specimens with both high sperm concentration and forward progression received the highest overestimations by visual rating. This was especially apparent in specimens with the highest motility. There was a statistically significant positive relationship between sperm motility and morphology rated on a one-by-one basis, but the relationship was too small to influence the visual rating of human sperm motility.

  13. Intestinal Neuromuscular Function after Preservation and Transplantation1

    PubMed Central

    Hamada, Nobuo; Hutson, William R.; Nakada, Koji; Ikoma, Akira; Suzuki, Tomomi; Zhu, Yue; Starzl, Thomas E.; Todo, Satoru

    2010-01-01

    While it is well known that prolonged preservation of the intestinal graft causes severe mucosal damage after transplantation, little is known about the effect on neuromuscular function. The entire small intestine of adult hound dogs was flushed and preserved with cold lactated Ringer’s solution and autotransplanted either immediately (n = 6) or after 24 hr (n = 6). Animals undergoing sham operation (n = 4) were used as a control. Fasting motility and the response of the intestinal smooth muscle and enteric nerves to bethanechol (100 μg/kg/0.5 hr, iv) and cisapride (0.5 mg/kg, iv) were determined by a multiple strain gauge method on Postoperative Days 2, 4, 7, 14, 21, and 28. Compared to the control, immediately transplanted grafts and those preserved for 24 hr developed delayed reappearance of migrating myoelectric complexes (MMC), hypercontractile activity, and reduced response to bethanechol and cisapride administration. Animals in the preservation group developed more abnormal fasting motility after transplantation, but responses to bethanechol and cisapride stimulation were not markedly different from those of the immediate group. The reappearance of MMC occurred 3 weeks postoperatively in the preservation group compared to 2 days in the immediate group. The results of our study indicate that intestinal dysmotility is augmented in prolonged-preservation grafts compared to those with brief preservation. The dysmotility was transient and normalized 3 to 4 weeks after surgery. Preservation and reperfusion injury to the neuromuscular system of intestinal grafts are reversible and are attenuated by simple hypothermia. PMID:8661243

  14. Trimebutine as a modulator of gastrointestinal motility.

    PubMed

    Lee, Hyun-Tai; Kim, Byung Joo

    2011-06-01

    Trimebutine has been used for treatment of both hypermotility and hypomotility disorders of the gastrointestinal (GI) tract, such as irritable bowel syndrome. In this issue, Tan et al. (2011) examined the concentration-dependent dual effects of trimebutine on colonic motility in guinea pig. The authors suggested that trimebutine attenuated colonic motility mainly through the inhibition of L-type Ca(2+) channels at higher concentrations, whereas, at lower concentrations, it depolarized membrane potentials by reducing BK(ca) currents, resulting in the enhancement of the muscle contractions. Trimebutine might be a plausible modulator of GI motility, which gives an insight in developing new prokinetic agents. Further studies to elucidate the effects of trimebutine on the interstitial cells of Cajal, the pacemaker in GI muscles would promote the therapeutic benefits as a GI modulator. PMID:21725804

  15. Direct Upstream Motility in Escherichia coli

    PubMed Central

    Kaya, Tolga; Koser, Hur

    2012-01-01

    We provide an experimental demonstration of positive rheotaxis (rapid and continuous upstream motility) in wild-type Escherichia coli freely swimming over a surface. This hydrodynamic phenomenon is dominant below a critical shear rate and robust against Brownian motion and cell tumbling. We deduce that individual bacteria entering a flow system can rapidly migrate upstream (>20 μm/s) much faster than a gradually advancing biofilm. Given a bacterial population with a distribution of sizes and swim speeds, local shear rate near the surface determines the dominant hydrodynamic mode for motility, i.e., circular or random trajectories for low shear rates, positive rheotaxis for moderate flow, and sideways swimming at higher shear rates. Faster swimmers can move upstream more rapidly and at higher shear rates, as expected. Interestingly, we also find on average that both swim speed and upstream motility are independent of cell aspect ratio. PMID:22500751

  16. Colonic manometry in children with chronic intestinal pseudo-obstruction.

    PubMed

    Di Lorenzo, C; Flores, A F; Reddy, S N; Snape, W J; Bazzocchi, G; Hyman, P E

    1993-06-01

    Pressure changes were evaluated in the transverse, descending, and rectosigmoid colon of 30 children with chronic intestinal pseudo-obstruction. Twenty two had severe lifelong constipation and eight had symptoms suggesting a motility disorder exclusively of the upper gastrointestinal tract. Based on prior antroduodenal manometry, 24 children were diagnosed as having a neuropathic and six a myopathic form of intestinal pseudo-obstruction. On the day of study, endoscopy was used to place a manometry catheter into the transverse colon and intraluminal pressure was recorded for more than four hours. After a baseline recording, we gave a meal to assess the gastrocolonic response. Colonic contractions were noted in 24 children. The six children with no colonic contractions had a hollow visceral myopathy and constipation. In the children with colonic contractions, fasting motility did not differentiate children with and without constipation. After the meal, in all eight children without constipation there was (1) an increase in motility index (3.2 (SEM 0.3) mm Hg/min basal v 8.4 (SEM 1.1) mm Hg/min postprandial; p < 0.001), and (2) at least one high amplitude propagated contraction (HAPC). In the 16 constipated children with colonic contractions the motility index did not significantly increase after the meal (2.1 (SEM 0.3) mm Hg/min basal v 3.1 (SEM 0.4) mm Hg/min postprandial) and 12 of them had no HAPCs (p < 0.01 v group without constipation). In summary, in children with a clinical diagnosis of chronic intestinal pseudo-obstruction, constipation is associated with absence of HAPCs, and the gastrocolonic response or with total absence of colonic contractions. It is concluded that studies of colonic manometry are feasible in children and may document discrete abnormalities in those with intestinal pseudo-obstruction with colonic involvement.

  17. Motor domain-based motility system and motile properties of alpha heavy chain in Tetrahymena outer arm dynein.

    PubMed

    Edamatsu, Masaki

    2014-10-24

    Axonemal dynein plays an essential role in ciliary motility, and impaired ciliary motility causes human diseases such as primary ciliary dyskinesia (PCD). The motor domain of axonemal dynein powers ciliary motility and its function is regulated by several accessary proteins bound to the tail region. Therefore, to understand the essential properties of dynein motility, examining the motile properties of the motor domain without the tail is necessary. In this study, the functional motor domain of the alpha heavy chain in Tetrahymena outer arm dynein was purified, and its motile properties were examined using an in vitro motility system. The purified protein caused microtubules to glide at a velocity of 5.0μm/s with their minus-end trailing, and motility was inhibited in an ATP concentration-dependent manner, which is in contrast with kinesin1. This method could be applicable to other axonemal dyneins and will enable further molecular studies on diverse axonemal dyneins and ciliary motility.

  18. Quinoa extract enriched in 20-hydroxyecdysone affects energy homeostasis and intestinal fat absorption in mice fed a high-fat diet.

    PubMed

    Foucault, Anne-Sophie; Even, Patrick; Lafont, René; Dioh, Waly; Veillet, Stanislas; Tomé, Daniel; Huneau, Jean-François; Hermier, Dominique; Quignard-Boulangé, Annie

    2014-04-10

    In a previous study, we have demonstrated that a supplementation of a high-fat diet with a quinoa extract enriched in 20-hydroxyecdysone (QE) or pure 20-hydroxyecdysone (20E) could prevent the development of obesity. In line with the anti-obesity effect of QE, we used indirect calorimetry to examine the effect of dietary QE and 20E in high-fat fed mice on different components of energy metabolism. Mice were fed a high-fat (HF) diet with or without supplementation by QE or pure 20E for 3 weeks. As compared to mice maintained on a low-fat diet, HF feeding resulted in a marked physiological shift in energy homeostasis, associating a decrease in global energy expenditure (EE) and an increase in lipid utilization as assessed by the lower respiratory quotient (RQ). Supplementation with 20E increased energy expenditure while food intake and activity were not affected. Furthermore QE and 20E promoted a higher rate of glucose oxidation leading to an increased RQ value. In QE and 20E-treated HFD fed mice, there was an increase in fecal lipid excretion without any change in stool amount. Our study indicates that anti-obesity effect of QE can be explained by a global increase in energy expenditure, a shift in glucose metabolism towards oxidation to the detriment of lipogenesis and a decrease in dietary lipid absorption leading to reduced dietary lipid storage in adipose tissue.

  19. Black tea extract and its thearubigins relieve the sildenafil-induced delayed gut motility in mice: a possible role of nitric oxide.

    PubMed

    Murad, Hussam A S; Abdallah, Hossam M

    2014-11-01

    In this study we hypothesize that a standardized black tea aqueous extract (BTE) and thearubigins, its main polyphenolic pigments, will improve sildenafil-induced delay in gastric emptying (GE) and small intestinal transit (SIT) in mice. Twenty groups of mice (n = 8) were given a phenol red meal, and three sets of experiments were performed. In the first and second sets, effects of different concentrations of BTE, thearubigins (TRs), and sildenafil (SLD), alone and in combinations, on GE and SIT were measured. In the third set, influence of nω -Nitro-l-arginine methyl ester hydrochloride (l-NAME) pretreatment on effects of these treatments was tested. Black tea extract (3% and 4.5%) and thearubigins (50 and 60 mg/kg) dose-dependently increased GE and SIT, whereas BTE 6% and thearubigins 70 mg/kg did not affect them. Sildenafil dose-dependently reduced both GE and SIT. Combination of metoclopramide, BTE 4.5%, thearubigins 60, or l-NAME with sildenafil (5 mg/kg) reversed its motility-delaying effects. Pretreatment with l-NAME followed by BTE 4.5%, thearubigins 60, BTE 4.5% + sildenafil 5, or thearubigins 60 + sildenafil 5 only partially affected the accelerating effects of BTE 4.5% and thearubigins 60. In conclusion, a standardized BTE and its thearubigins improve the sildenafil-induced delayed gut motility in mice. This improvement was partially blocked by l-NAME suggesting a possible role of nitric oxide. Thus, BTE 4.5% or TRs 60 mg/kg solution could be considered a reliever therapy for the sildenafil-induced dyspepsia.

  20. Adipose triglyceride lipase is a TG hydrolase of the small intestine and regulates intestinal PPARα signaling.

    PubMed

    Obrowsky, Sascha; Chandak, Prakash G; Patankar, Jay V; Povoden, Silvia; Schlager, Stefanie; Kershaw, Erin E; Bogner-Strauss, Juliane G; Hoefler, Gerald; Levak-Frank, Sanja; Kratky, Dagmar

    2013-02-01

    Adipose triglyceride lipase (ATGL) is the rate-limiting enzyme mediating triglyceride (TG) hydrolysis. The lack of ATGL results in TG accumulation in multiple tissues, underscoring the critical role of ATGL in maintaining lipid homeostasis. Recent evidence suggests that ATGL affects TG metabolism via activation of peroxisome proliferator-activated receptor α (PPARα). To investigate specific effects of intestinal ATGL on lipid metabolism we generated mice lacking ATGL exclusively in the intestine (ATGLiKO). We found decreased TG hydrolase activity and increased intracellular TG content in ATGLiKO small intestines. Intragastric administration of [(3)H]trioleate resulted in the accumulation of radioactive TG in the intestine, whereas absorption into the systemic circulation was unchanged. Intraperitoneally injected [(3)H]oleate also accumulated within TG in ATGLiKO intestines, indicating that ATGL mobilizes fatty acids from the systemic circulation absorbed by the basolateral side from the blood. Down-regulation of PPARα target genes suggested modulation of cholesterol absorption by intestinal ATGL. Accordingly, ATGL deficiency in the intestine resulted in delayed cholesterol absorption. Importantly, this study provides evidence that ATGL has no impact on intestinal TG absorption but hydrolyzes TGs taken up from the intestinal lumen and systemic circulation. Our data support the role of ATGL in modulating PPARα-dependent processes also in the small intestine.

  1. Plasmodium berghei ANKA causes intestinal malaria associated with dysbiosis.

    PubMed

    Taniguchi, Tomoyo; Miyauchi, Eiji; Nakamura, Shota; Hirai, Makoto; Suzue, Kazutomo; Imai, Takashi; Nomura, Takahiro; Handa, Tadashi; Okada, Hiroko; Shimokawa, Chikako; Onishi, Risa; Olia, Alex; Hirata, Jun; Tomita, Haruyoshi; Ohno, Hiroshi; Horii, Toshihiro; Hisaeda, Hajime

    2015-10-27

    Gastrointestinal symptoms, such as abdominal pain and diarrhea, are frequently observed in patients with Plasmodium falciparum malaria. However, the correlation between malaria intestinal pathology and intestinal microbiota has not been investigated. In the present study, infection of C57BL/6 mice with P. berghei ANKA (PbA) caused intestinal pathological changes, such as detachment of epithelia in the small intestines and increased intestinal permeability, which correlated with development with experimental cerebral malaria (ECM). Notably, an apparent dysbiosis occurred, characterized by a reduction of Firmicutes and an increase in Proteobacteria. Furthermore, some genera of microbiota correlated with parasite growth and/or ECM development. By contrast, BALB/c mice are resistant to ECM and exhibit milder intestinal pathology and dysbiosis. These results indicate that the severity of cerebral and intestinal pathology coincides with the degree of alteration in microbiota. This is the first report demonstrating that malaria affects intestinal microbiota and causes dysbiosis.

  2. Plasmodium berghei ANKA causes intestinal malaria associated with dysbiosis

    PubMed Central

    Taniguchi, Tomoyo; Miyauchi, Eiji; Nakamura, Shota; Hirai, Makoto; Suzue, Kazutomo; Imai, Takashi; Nomura, Takahiro; Handa, Tadashi; Okada, Hiroko; Shimokawa, Chikako; Onishi, Risa; Olia, Alex; Hirata, Jun; Tomita, Haruyoshi; Ohno, Hiroshi; Horii, Toshihiro; Hisaeda, Hajime

    2015-01-01

    Gastrointestinal symptoms, such as abdominal pain and diarrhea, are frequently observed in patients with Plasmodium falciparum malaria. However, the correlation between malaria intestinal pathology and intestinal microbiota has not been investigated. In the present study, infection of C57BL/6 mice with P. berghei ANKA (PbA) caused intestinal pathological changes, such as detachment of epithelia in the small intestines and increased intestinal permeability, which correlated with development with experimental cerebral malaria (ECM). Notably, an apparent dysbiosis occurred, characterized by a reduction of Firmicutes and an increase in Proteobacteria. Furthermore, some genera of microbiota correlated with parasite growth and/or ECM development. By contrast, BALB/c mice are resistant to ECM and exhibit milder intestinal pathology and dysbiosis. These results indicate that the severity of cerebral and intestinal pathology coincides with the degree of alteration in microbiota. This is the first report demonstrating that malaria affects intestinal microbiota and causes dysbiosis. PMID:26503461

  3. Roles of Pseudomonas aeruginosa las and rhl Quorum-Sensing Systems in Control of Twitching Motility

    PubMed Central

    Glessner, Alex; Smith, Roger S.; Iglewski, Barbara H.; Robinson, Jayne B.

    1999-01-01

    Pseudomonas aeruginosa is a ubiquitous environmental bacterium and an important human pathogen. The production of several virulence factors by P. aeruginosa is controlled through two quorum-sensing systems, las and rhl. We have obtained evidence that both the las and rhl quorum-sensing systems are also required for type 4 pilus-dependent twitching motility and infection by the pilus-specific phage D3112cts. Mutants which lack the ability to synthesize PAI-1, PAI-2, or both autoinducers were significantly or greatly impaired in twitching motility and in susceptibility to D3112cts. Twitching motility and phage susceptibility in the autoinducer-deficient mutants were partially restored by exposure to exogenous PAI-1 and PAI-2. Both twitching motility and infection by pilus-specific phage are believed to be dependent on the extension and retraction of polar type 4 pili. Western blot analysis of whole-cell lysates and enzyme-linked immunosorbent assays of intact cells were used to measure the amounts of pilin on the cell surfaces of las and rhl mutants relative to that of the wild type. It appears that PAI-2 plays a crucial role in twitching motility and phage infection by affecting the export and assembly of surface type 4 pili. The ability of P. aeruginosa cells to adhere to human bronchial epithelial cells was also found to be dependent on the rhl quorum-sensing system. Microscopic analysis of twitching motility indicated that mutants which were unable to synthesize PAI-1 were defective in the maintenance of cellular monolayers and migrating packs of cells. Thus, PAI-1 appears to have an essential role in maintaining cell-cell spacing and associations required for effective twitching motility. PMID:10049396

  4. SHP-2 phosphatase activity is required for PECAM-1-dependent cell motility.

    PubMed

    Zhu, Jing-Xu; Cao, Gaoyuan; Williams, James T; Delisser, Horace M

    2010-10-01

    Platelet endothelial cell adhesion molecule-1 (PECAM-1) has been implicated in endothelial cell motility during angiogenesis. Although there is evidence that SHP-2 plays a role in PECAM-1-dependent cell motility, the molecular basis of the activity of SHP-2 in this process has not been defined. To investigate the requirement of SHP-2 in PECAM-1-dependent cell motility, studies were done in which various constructs of SHP-2 were expressed in cell transfectants expressing PECAM-1. We observed that the levels of PECAM-1 tyrosine phosphorylation and SHP-2 association with PECAM-1 were significantly increased in cells expressing a phosphatase-inactive SHP-2 mutant, suggesting that the level of PECAM-1 tyrosine phosphorylation, and thus SHP-2 binding are regulated in part by bound, catalytically active SHP-2. We subsequently found that expression of PECAM-1 stimulated wound-induced migration and the formation of filopodia (a morphological feature of motile cells). These activities were associated with increased mitogen-activated protein kinase (MAPK) activation and the dephosphorylation of paxillin (an event implicated in the activation of MAPK). The phosphatase-inactive SHP-2 mutant, however, suppressed these PECAM-1-dependent phenomena, whereas the activity of PECAM-1 expressing cells was not altered by expression of wild-type SHP-2 or SHP-2 in which the scaffold/adaptor function had been disabled. Pharmacological inhibition of SHP-2 phosphatase activity also suppressed PECAM-1-dependent motility. Furthermore, PECAM-1 expression also stimulates tube formation, but none of the SHP-2 constructs affected this process. These findings therefore suggest a model for the involvement of SHP-2 in PECAM-1-dependent motility in which SHP-2, recruited by its interaction with PECAM-1, targets paxillin to ultimately activate the MAPK pathway and downstream events required for cell motility. PMID:20631249

  5. Flagellar motility of the pathogenic spirochetes.

    PubMed

    Wolgemuth, Charles W

    2015-10-01

    Bacterial pathogens are often classified by their toxicity and invasiveness. The invasiveness of a given bacterium is determined by how capable the bacterium is at invading a broad range of tissues in its host. Of mammalian pathogens, some of the most invasive come from a group of bacteria known as the spirochetes, which cause diseases, such as syphilis, Lyme disease, relapsing fever and leptospirosis. Most of the spirochetes are characterized by their distinct shapes and unique motility. They are long, thin bacteria that can be shaped like flat-waves, helices, or have more irregular morphologies. Like many other bacteria, the spirochetes use long, helical appendages known as flagella to move; however, the spirochetes enclose their flagella in the periplasm, the narrow space between the inner and outer membranes. Rotation of the flagella in the periplasm causes the entire cell body to rotate and/or undulate. These deformations of the bacterium produce the force that drives the motility of these organisms, and it is this unique motility that likely allows these bacteria to be highly invasive in mammals. This review will describe the current state of knowledge on the motility and biophysics of these organisms and provide evidence on how this knowledge can inform our understanding of spirochetal diseases. PMID:26481969

  6. Early endosome motility spatially organizes polysome distribution.

    PubMed

    Higuchi, Yujiro; Ashwin, Peter; Roger, Yvonne; Steinberg, Gero

    2014-02-01

    Early endosomes (EEs) mediate protein sorting, and their cytoskeleton-dependent motility supports long-distance signaling in neurons. Here, we report an unexpected role of EE motility in distributing the translation machinery in a fungal model system. We visualize ribosomal subunit proteins and show that the large subunits diffused slowly throughout the cytoplasm (Dc,60S = 0.311 µm(2)/s), whereas entire polysomes underwent long-range motility along microtubules. This movement was mediated by "hitchhiking" on kinesin-3 and dynein-driven EEs, where the polysomes appeared to translate EE-associated mRNA into proteins. Modeling indicates that this motor-driven transport is required for even cellular distribution of newly formed ribosomes. Indeed, impaired EE motility in motor mutants, or their inability to bind EEs in mutants lacking the RNA-binding protein Rrm4, reduced ribosome transport and induced ribosome aggregation near the nucleus. As a consequence, cell growth was severely restricted. Collectively, our results indicate that polysomes associate with moving EEs and that "off- and reloading" distributes the protein translation machinery.

  7. Semiautomated Motility Assay For Determining Toxicity

    NASA Technical Reports Server (NTRS)

    Noever, David A.; Cronise, Raymond

    1996-01-01

    Improved method of assessing toxicities of various substances based on observation of effects of those substances on motilities of manageably small number of cells of protozoan species Tetrahema pyriformis. Provides repeatable, standardized tests with minimal handling by technicians and with minimal exposure of technicians to chemicals. Rapid and economical alternative to Draize test.

  8. Integrin Molecular Tension within Motile Focal Adhesions.

    PubMed

    Wang, Xuefeng; Sun, Jie; Xu, Qian; Chowdhury, Farhan; Roein-Peikar, Mehdi; Wang, Yingxiao; Ha, Taekjip

    2015-12-01

    Forces transmitted by integrins regulate many important cellular functions. Previously, we developed tension gauge tether (TGT) as a molecular force sensor and determined the threshold tension across a single integrin-ligand bond, termed integrin tension, required for initial cell adhesion. Here, we used fluorescently labeled TGTs to study the magnitude and spatial distribution of integrin tension on the cell-substratum interface. We observed two distinct levels of integrin tension. A >54 pN molecular tension is transmitted by clustered integrins in motile focal adhesions (FAs) and such force is generated by actomyosin, whereas the previously reported ∼40 pN integrin tension is transmitted by integrins before FA formation and is independent of actomyosin. We then studied FA motility using a TGT-coated surface as a fluorescent canvas, which records the history of integrin force activity. Our data suggest that the region of the strongest integrin force overlaps with the center of a motile FA within 0.2 μm resolution. We also found that FAs move in pairs and that the asymmetry in the motility of an FA pair is dependent on the initial FA locations on the cell-substratum interface.

  9. Flagellar motility of the pathogenic spirochetes

    PubMed Central

    Wolgemuth, Charles W.

    2016-01-01

    Bacterial pathogens are often classified by their toxicity and invasiveness. The invasiveness of a given bacterium is determined by how capable the bacterium is at invading a broad range of tissues in its host. Of mammalian pathogens, some of the most invasive come from a group of bacteria known as the spirochetes, which cause diseases such as syphilis, Lyme disease, relapsing fever and leptospirosis. Most of the spirochetes are characterized by their distinct shapes and unique motility. They are long, thin bacteria that can be shaped like flat-waves, helices, or have more irregular morphologies. Like many other bacteria, the spirochetes use long, helical appendages known as flagella to move; however, the spirochetes enclose their flagella in the periplasm, the narrow space between the inner and outer membranes. Rotation of the flagella in the periplasm causes the entire cell body to rotate and/or undulate. These deformations of the bacterium produce the force that drives the motility of these organisms, and it is this unique motility that likely allows these bacteria to be highly invasive in mammals. This review will describe the current state of knowledge on the motility and biophysics of these organisms and provide evidence on how this knowledge can inform our understanding of spirochetal diseases. PMID:26481969

  10. Targeting tumor cell motility to prevent metastasis

    PubMed Central

    Palmer, Trenis D.; Ashby, William J.; Lewis, John D.; Zijlstra, Andries

    2011-01-01

    Mortality and morbidity in patients with solid tumors invariably results from the disruption of normal biological function caused by disseminating tumor cells. Tumor cell migration is under intense investigation as the underlying cause of cancer metastasis. The need for tumor cell motility in the progression of metastasis has been established experimentally and is supported empirically by basic and clinical research implicating a large collection of migration-related genes. However, there are few clinical interventions designed to specifically target the motility of tumor cells and adjuvant therapy to specifically prevent cancer cell dissemination is severely limited. In an attempt to define motility targets suitable for treating metastasis, we have parsed the molecular determinants of tumor cell motility into five underlying principles including cell autonomous ability, soluble communication, cell-cell adhesion, cell-matrix adhesion, and integrating these determinants of migration on molecular scaffolds. The current challenge is to implement meaningful and sustainable inhibition of metastasis by developing clinically viable disruption of molecular targets that control these fundamental capabilities. PMID:21664937

  11. Unraveling the ties between irritable bowel syndrome and intestinal microbiota

    PubMed Central

    Hong, Sung Noh; Rhee, Poong-Lyul

    2014-01-01

    Irritable bowel syndrome (IBS) is the most prevalent functional gastrointestinal disorder. It is a multifactorial disorder. Intestinal microbiota may cause the pathogenesis of IBS by contributing to abnormal gastrointestinal motility, low-grade inflammation, visceral hypersensitivity, communication in the gut-brain axis, and so on. Previous attempts to identify the intestinal microbiota composition in IBS patients have yielded inconsistent and occasionally contradictory results. This inconsistency may be due to the differences in the molecular techniques employed, the sample collection and handling methods, use of single samples that are not linked to fluctuating symptoms, or other factors such as patients’ diets and phenotypic characterizations. Despite these difficulties, previous studies found that the intestinal microbiota in some IBS patients was completely different from that in healthy controls, and there does appear to be a consistent theme of Firmicutes enrichment and reduced abundance of Bacteroides. Based on the differences in intestinal microbiota composition, many studies have addressed the roles of microbiota-targeted treatments, such as antibiotics and probiotics, in alleviating certain symptoms of IBS. This review summarizes the current knowledge of the associations between intestinal microbiota and IBS as well as the possible modes of action of intestinal microbiota in the pathogenesis of IBS. Improving the current level of understanding of host-microbiota interactions in IBS is important not only for determining the role of intestinal microbiota in IBS pathogenesis but also for therapeutic modulation of the microbiota. PMID:24627584

  12. The motility of Chara corallina myosin was inhibited reversibly by 2,3-butanedione monoxime (BDM).

    PubMed

    Funaki, Keisuke; Nagata, Ayumi; Akimoto, Youka; Shimada, Kiyo; Ito, Kohji; Yamamoto, Keiichi

    2004-09-01

    We studied the effects of 2,3-butanedione monoxime (BDM) on the cytoplasmic streaming of Chara corallina and on the motility of myosin prepared from the same plant to examine whether this reagent really affects the plant class XI myosin. It was found that BDM inhibited both cytoplasmic streaming and the motility of myosin at a very similar concentration range (10-100 mM). BDM introduced directly into tonoplast-free cells also inhibited cytoplasmic streaming. These results suggested that effect of BDM on cytoplasmic streaming was exerted through myosin and not through ion channels at least in Chara corallina, though a very high concentration of BDM was required.

  13. Targeting ion channels for the treatment of gastrointestinal motility disorders

    PubMed Central

    Beyder, Arthur

    2012-01-01

    Gastrointestinal (GI) functional and motility disorders are highly prevalent and responsible for long-term morbidity and sometimes mortality in the affected patients. It is estimated that one in three persons has a GI functional or motility disorder. However, diagnosis and treatment of these widespread conditions remains challenging. This partly stems from the multisystem pathophysiology, including processing abnormalities in the central and peripheral (enteric) nervous systems and motor dysfunction in the GI wall. Interstitial cells of Cajal (ICCs) are central to the generation and propagation of the cyclical electrical activity and smooth muscle cells (SMCs) are responsible for electromechanical coupling. In these and other excitable cells voltage-sensitive ion channels (VSICs) are the main molecular units that generate and regulate electrical activity. Thus, VSICs are potential targets for intervention in GI motility disorders. Research in this area has flourished with advances in the experimental methods in molecular and structural biology and electrophysiology. However, our understanding of the molecular mechanisms responsible for the complex and variable electrical behavior of ICCs and SMCs remains incomplete. In this review, we focus on the slow waves and action potentials in ICCs and SMCs. We describe the constituent VSICs, which include voltage-gated sodium (NaV), calcium (CaV), potassium (KV, KCa), chloride (Cl–) and nonselective ion channels (transient receptor potentials [TRPs]). VSICs have significant structural homology and common functional mechanisms. We outline the approaches and limitations and provide examples of targeting VSICs at the pores, voltage sensors and alternatively spliced sites. Rational drug design can come from an integrated view of the structure and mechanisms of gating and activation by voltage or mechanical stress. PMID:22282704

  14. Is there a role for human pluripotent stem cells in modelling interstitial cells of Cajal and gut motility disorders?

    PubMed

    Meng, Wenbo; Zhou, Jerry; Elliott, Ross; Murphy, Patricia; Ho, Vincent; O'Connor, Michael

    2015-01-01

    Gastrointestinal motility disorders affect millions of people worldwide, resulting in significant morbidity and mortality. Current treatments for these disorders are inadequate and often provide little to no relief for patients. As a result, gastrointestinal motility disorders produce substantial long-term social and economic burdens in both developed and developing countries. These limited treatment options arise largely from our relatively poor understanding of the molecular etiology for the majority of gastrointestinal motility disorders. In turn, this is due to our limited access to normal or diseased human gut tissue for use in research. In particular while the interstitial cells of Cajal (ICC) are known to be important for gastrointestinal motility, little is known of how these cells function or how they are involved in disease initiation and progression. The advent of human pluripotent stem cell technology offers an opportunity to generate large amounts of human tissue for both research and clinical applications. The application of this technology to gastrointestinal motility disorders is currently only in its infancy and as yet no studies have described ICC production from human pluripotent cells. By considering the present understanding of the anatomical, cellular and molecular basis of gut motility with particular emphasis on ICC, this review provides a clear framework for the application of human pluripotent stem cell technology to answer fundamental questions of ICC involvement in gut motility. PMID:25391378

  15. Tibetan herbal formula Padma Digestin modulates gastrointestinal motility in vitro

    PubMed Central

    Balsiger, Bruno M; Krayer, Magali; Rickenbacher, Andreas; Flogerzi, Beatrice; Vennos, Cecile; Gschossmann, Juergen M

    2013-01-01

    AIM: To examine the effects of Padma Digestin on the smooth muscle motility of different gastrointestinal segments in vitro. METHODS: The effects of the ethanolic extract of Padma Digestin (at 8.16 mg/mL or 81.6 mg/mL) on the contractility and susceptibility to acetylcholine (ACh) of muscle strips from the cardia, antrum, pylorus, duodenum, jejunum, ileum and colon of male Wistar rats were analyzed. RESULTS: Compared with the control treatment, the Padma Digestin extract had a procontractile effect on the antral smooth muscle strips. Padma Digestin decreased ACh sensitivity in cardia muscle strips and increased it in those from the antrum and pylorus. In the intestinal segments, spontaneous contractility was inhibited in both the duodenal and jejunal strips, whereas reactivity to ACh was inhibited in the jejunal strips only. In the colonic samples, Padma Digestin inhibited spontaneous and ACh-stimulated contractility at a low dose but seems to have increasing effects at a high dose. CONCLUSION: Padma Digestin extract has region-specific effects on the contractility and excitability of gastrointestinal smooth muscle. Our results support the traditional use of Padma Digestin for maldigestion and functional gastrointestinal disorders. PMID:23515138

  16. Colony Expansion of Socially Motile Myxococcus xanthus Cells Is Driven by Growth, Motility, and Exopolysaccharide Production

    PubMed Central

    Patra, Pintu; Kissoon, Kimberley; Cornejo, Isabel; Kaplan, Heidi B.; Igoshin, Oleg A.

    2016-01-01

    Myxococcus xanthus, a model organism for studies of multicellular behavior in bacteria, moves exclusively on solid surfaces using two distinct but coordinated motility mechanisms. One of these, social (S) motility is powered by the extension and retraction of type IV pili and requires the presence of exopolysaccharides (EPS) produced by neighboring cells. As a result, S motility requires close cell-to-cell proximity and isolated cells do not translocate. Previous studies measuring S motility by observing the colony expansion of cells deposited on agar have shown that the expansion rate increases with initial cell density, but the biophysical mechanisms involved remain largely unknown. To understand the dynamics of S motility-driven colony expansion, we developed a reaction-diffusion model describing the effects of cell density, EPS deposition and nutrient exposure on the expansion rate. Our results show that at steady state the population expands as a traveling wave with a speed determined by the interplay of cell motility and growth, a well-known characteristic of Fisher’s equation. The model explains the density-dependence of the colony expansion by demonstrating the presence of a lag phase–a transient period of very slow expansion with a duration dependent on the initial cell density. We propose that at a low initial density, more time is required for the cells to accumulate enough EPS to activate S-motility resulting in a longer lag period. Furthermore, our model makes the novel prediction that following the lag phase the population expands at a constant rate independent of the cell density. These predictions were confirmed by S motility experiments capturing long-term expansion dynamics. PMID:27362260

  17. Colony Expansion of Socially Motile Myxococcus xanthus Cells Is Driven by Growth, Motility, and Exopolysaccharide Production.

    PubMed

    Patra, Pintu; Kissoon, Kimberley; Cornejo, Isabel; Kaplan, Heidi B; Igoshin, Oleg A

    2016-06-01

    Myxococcus xanthus, a model organism for studies of multicellular behavior in bacteria, moves exclusively on solid surfaces using two distinct but coordinated motility mechanisms. One of these, social (S) motility is powered by the extension and retraction of type IV pili and requires the presence of exopolysaccharides (EPS) produced by neighboring cells. As a result, S motility requires close cell-to-cell proximity and isolated cells do not translocate. Previous studies measuring S motility by observing the colony expansion of cells deposited on agar have shown that the expansion rate increases with initial cell density, but the biophysical mechanisms involved remain largely unknown. To understand the dynamics of S motility-driven colony expansion, we developed a reaction-diffusion model describing the effects of cell density, EPS deposition and nutrient exposure on the expansion rate. Our results show that at steady state the population expands as a traveling wave with a speed determined by the interplay of cell motility and growth, a well-known characteristic of Fisher's equation. The model explains the density-dependence of the colony expansion by demonstrating the presence of a lag phase-a transient period of very slow expansion with a duration dependent on the initial cell density. We propose that at a low initial density, more time is required for the cells to accumulate enough EPS to activate S-motility resulting in a longer lag period. Furthermore, our model makes the novel prediction that following the lag phase the population expands at a constant rate independent of the cell density. These predictions were confirmed by S motility experiments capturing long-term expansion dynamics.

  18. Effects of Motility and Adsorption Rate Coefficient on Transport of Bacteria through Saturated Porous Media

    PubMed Central

    Camper, Anne K.; Hayes, Jason T.; Sturman, Paul J.; Jones, Warren L.; Cunningham, Alfred B.

    1993-01-01

    Three strains of Pseudomonas fluorescens with different motility rates and adsorption rate coefficients were injected into porous-medium reactors packed with l-mm-diameter glass spheres. Cell breakthrough, time to peak concentration, tailing, and cell recovery were measured at three interstitial pore velocities (higher than, lower than, and much lower than the maximal bacterial motility rate). All experiments were done with distilled water to reduce the effects of growth and chemotaxis. Contrary to expectations, motility did not result in either early breakthrough or early time to peak concentration at flow velocities below the motility rate. Bacterial size exclusion effects were shown to affect breakthrough curve shape at the very low flow velocity, but no such effect was seen at the higher flow velocity. The tendency of bacteria to adsorb to porous-medium surfaces, as measured by adsorption rate coefficients, profoundly influenced transport characteristics. Cell recoveries were shown to be correlated with the ratio of advective to adsorptive transport in the reactors. Adsorption rate coefficients were found to be better predictors of microbial transport phenomena than individual characteristics, such as size, motility, or porous-medium hydrodynamics. PMID:16349075

  19. Swimming motility plays a key role in the stochastic dynamics of cell clumping

    NASA Astrophysics Data System (ADS)

    Qi, Xianghong; Nellas, Ricky B.; Byrn, Matthew W.; Russell, Matthew H.; Bible, Amber N.; Alexandre, Gladys; Shen, Tongye

    2013-04-01

    Dynamic cell-to-cell interactions are a prerequisite to many biological processes, including development and biofilm formation. Flagellum induced motility has been shown to modulate the initial cell-cell or cell-surface interaction and to contribute to the emergence of macroscopic patterns. While the role of swimming motility in surface colonization has been analyzed in some detail, a quantitative physical analysis of transient interactions between motile cells is lacking. We examined the Brownian dynamics of swimming cells in a crowded environment using a model of motorized adhesive tandem particles. Focusing on the motility and geometry of an exemplary motile bacterium Azospirillum brasilense, which is capable of transient cell-cell association (clumping), we constructed a physical model with proper parameters for the computer simulation of the clumping dynamics. By modulating mechanical interaction (‘stickiness’) between cells and swimming speed, we investigated how equilibrium and active features affect the clumping dynamics. We found that the modulation of active motion is required for the initial aggregation of cells to occur at a realistic time scale. Slowing down the rotation of flagellar motors (and thus swimming speeds) is correlated to the degree of clumping, which is consistent with the experimental results obtained for A. brasilense.

  20. Experimental and Mathematical-Modeling Characterization of Trypanosoma cruzi Epimastigote Motility.

    PubMed

    Sosa-Hernández, Eduardo; Ballesteros-Rodea, Gilberto; Arias-Del-Angel, Jorge A; Dévora-Canales, Diego; Manning-Cela, Rebeca G; Santana-Solano, Jesús; Santillán, Moisés

    2015-01-01

    The present work is aimed at characterizing the motility of parasite T. cruzi in its epimastigote form. To that end, we recorded the trajectories of two strains of this parasite (a wild-type strain and a stable transfected strain, which contains an ectopic copy of LYT1 gene and whose motility is known to be affected). We further extracted parasite trajectories from the recorded videos, and statistically analysed the following trajectory-step features: step length, angular change of direction, longitudinal and transverse displacements with respect to the previous step, and mean square displacement. Based on the resulting observations, we developed a mathematical model to simulate parasite trajectories. The fact that the model predictions closely match most of the experimentally observed parasite-trajectory characteristics, allows us to conclude that the model is an accurate description of T. cruzi motility. PMID:26544863

  1. Oda16/Wdr69 is essential for axonemal dynein assembly and ciliary motility during zebrafish embryogenesis.

    PubMed

    Gao, Chunlei; Wang, Guangliang; Amack, Jeffrey D; Mitchell, David R

    2010-08-01

    In the alga Chlamydomonas reinhardtii, Oda16 functions during ciliary assembly as an adaptor for intraflagellar transport of outer arm dynein. Oda16 orthologs only occur in genomes of organisms that use motile cilia; however, such cilia play multiple roles during vertebrate development and the contribution of Oda16 to their assembly remains unexplored. We demonstrate that the zebrafish Oda16 ortholog (Wdr69) is expressed in organs with motile cilia and retains a role in dynein assembly. Antisense morpholino knockdown of Wdr69 disrupts ciliary motility and results in multiple phenotypes associated with vertebrate ciliopathies. Affected cilia included those in Kupffer's vesicle, where Wdr69 plays a role in generation of asymmetric fluid flow and establishment of organ laterality, and otic vesicles, where Wdr69 is needed to develop normal numbers of otoliths. Analysis of cilium ultrastructure revealed loss of outer dynein arms in morphant embryos. These results support a remarkable level of functional conservation for Oda16/Wdr69. PMID:20568242

  2. Experimental and Mathematical-Modeling Characterization of Trypanosoma cruzi Epimastigote Motility

    PubMed Central

    Arias-del-Angel, Jorge A.; Dévora-Canales, Diego; Manning-Cela, Rebeca G.; Santana-Solano, Jesús; Santillán, Moisés

    2015-01-01

    The present work is aimed at characterizing the motility of parasite T. cruzi in its epimastigote form. To that end, we recorded the trajectories of two strains of this parasite (a wild-type strain and a stable transfected strain, which contains an ectopic copy of LYT1 gene and whose motility is known to be affected). We further extracted parasite trajectories from the recorded videos, and statistically analysed the following trajectory-step features: step length, angular change of direction, longitudinal and transverse displacements with respect to the previous step, and mean square displacement. Based on the resulting observations, we developed a mathematical model to simulate parasite trajectories. The fact that the model predictions closely match most of the experimentally observed parasite-trajectory characteristics, allows us to conclude that the model is an accurate description of T. cruzi motility. PMID:26544863

  3. 21 CFR 876.1725 - Gastrointestinal motility monitoring system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Gastrointestinal motility monitoring system. 876... Gastrointestinal motility monitoring system. (a) Identification. A gastrointestinal motility monitoring system is a... include signal conditioning, amplifying, and recording equipment. This generic type of device includes...

  4. Small Intestine Disorders

    MedlinePlus

    Your small intestine is the longest part of your digestive system - about twenty feet long! It connects your stomach to ... many times to fit inside your abdomen. Your small intestine does most of the digesting of the foods ...

  5. Intestinal obstruction repair

    MedlinePlus

    Repair of volvulus; Intestinal volvulus - repair; Bowel obstruction - repair ... Intestinal obstruction repair is done while you are under general anesthesia . This means you are asleep and DO NOT feel pain. ...

  6. Large intestine (colon) (image)

    MedlinePlus

    ... portion of the digestive system most responsible for absorption of water from the indigestible residue of food. The ileocecal valve of the ileum (small intestine) passes material into the large intestine at the ...

  7. Vasoactive intestinal peptide test

    MedlinePlus

    ... medlineplus.gov/ency/article/003508.htm Vasoactive intestinal peptide test To use the sharing features on this page, please enable JavaScript. Vasoactive intestinal peptide (VIP) is a test that measures the amount ...

  8. Targeting extra-oral bitter taste receptors modulates gastrointestinal motility with effects on satiation

    PubMed Central

    Avau, Bert; Rotondo, Alessandra; Thijs, Theo; Andrews, Christopher N.; Janssen, Pieter; Tack, Jan; Depoortere, Inge

    2015-01-01

    Bitter taste receptors (TAS2Rs) are present in extra-oral tissues, including gut endocrine cells. This study explored the presence and mechanism of action of TAS2R agonists on gut smooth muscle in vitro and investigated functional effects of intra-gastric administration of TAS2R agonists on gastric motility and satiation. TAS2Rs and taste signalling elements were expressed in smooth muscle tissue along the mouse gut and in human gastric smooth muscle cells (hGSMC). Bitter tastants induced concentration and region-dependent contractility changes in mouse intestinal muscle strips. Contractions induced by denatonium benzoate (DB) in gastric fundus were mediated via increases in intracellular Ca2+ release and extracellular Ca2+-influx, partially masked by a hyperpolarizing K+-efflux. Intra-gastric administration of DB in mice induced a TAS2R-dependent delay in gastric emptying. In hGSMC, bitter compounds evoked Ca2+-rises and increased ERK-phosphorylation. Healthy volunteers showed an impaired fundic relaxation in response to nutrient infusion and a decreased nutrient volume tolerance and increased satiation during an oral nutrient challenge test after intra-gastric DB administration. These findings suggest a potential role for intestinal TAS2Rs as therapeutic targets to alter gastrointestinal motility and hence to interfere with hunger signalling. PMID:26541810

  9. Single molecular observation of self-regulated kinesin motility.

    PubMed

    Watanabe, Tomonobu M; Yanagida, Toshio; Iwane, Atsuko H

    2010-06-01

    Kinesin-1 is an ATP-driven molecular motor that transports various cargoes in cells, a process that can be regulated by the kinesin tail domain. Here, kinesin ATPase activity and motility were inhibited in vitro by interacting the kinesin heavy chain C-terminal tail domain with the kinesin N-terminal motor domain. Though the tail domain can directly interact with microtubules, we found 70% of tail domains failed to bind in the presence of >100 mM (high) KCl, which also modulated the ATPase inhibition manner. These observations suggest that self-inhibition of kinesin depends on electrostatic interactions between the motor domain, the tail domain, and a microtubule. Furthermore, we observed self-regulated behavior of kinesin at the single molecule level. The tail domain did not affect motility velocity, but it did lower the binding affinity of the motor domain to the microtubule. The decrement in binding was coupled to ATPase inhibition. Meanwhile, the tail domain transfected into living cells not only failed to bind to microtubules but also inhibited the motor domain and microtubule interaction, in agreement with our in vitro results. Furthermore, at high potassium concentrations, the self-regulation of kinesin observed in cells was like that in vitro. The results favor a way tail inhibition mechanism where the tail domain masks the microtubule binding site of the motor domain in high potassium concentration. PMID:20446754

  10. Modulation of Chlamydomonas reinhardtii flagellar motility by redox poise

    PubMed Central

    Wakabayashi, Ken-ichi; King, Stephen M.

    2006-01-01

    Redox-based regulatory systems are essential for many cellular activities. Chlamydomonas reinhardtii exhibits alterations in motile behavior in response to different light conditions (photokinesis). We hypothesized that photokinesis is signaled by variations in cytoplasmic redox poise resulting from changes in chloroplast activity. We found that this effect requires photosystem I, which generates reduced NADPH. We also observed that photokinetic changes in beat frequency and duration of the photophobic response could be obtained by altering oxidative/reductive stress. Analysis of reactivated cell models revealed that this redox poise effect is mediated through the outer dynein arms (ODAs). Although the global redox state of the thioredoxin-related ODA light chains LC3 and LC5 and the redox-sensitive Ca2+-binding subunit of the docking complex DC3 did not change upon light/dark transitions, we did observe significant alterations in their interactions with other flagellar components via mixed disulfides. These data indicate that redox poise directly affects ODAs and suggest that it may act in the control of flagellar motility. PMID:16754958

  11. Uterine rotation: a cause of intestinal obstruction.

    PubMed

    González-Mesa, Ernesto; Narbona, Isidoro; Cohen, Isaac; Villegas, Emilia; Cuenca, Celia

    2013-01-01

    Intestinal obstruction is an uncommon surgical emergency during pregnancy that affects seriously the prognosis of gestation. The underlying cause can be identified in the majority of cases and usually consists of adhesions secondary to previous abdominal or pelvic surgery, followed in order of frequency by intestinal volvuli. In recent years there have been no reports in which the gravid uterus has been the cause of intestinal obstruction. We report the case of a woman in week 33 + 4 of pregnancy who developed extrinsic compression of the colon secondary to uterine rotation and pelvic impaction of the head of the fetus.

  12. MOTILITY, AGGRESSION, AND THE BODILY I: AN INTERPRETATION OF WINNICOTT.

    PubMed

    Elkins, Jeremy

    2015-10-01

    Among the central ideas associated with the name of Winnicott, scant mention is made of motility. This is largely attributable to Winnicott himself, who never thematized motility and never wrote a paper specifically devoted to the topic. This paper suggests both that the idea of motility is nonetheless of central significance in Winnicott's thought, and that motility is of central importance in the development and constitution of the bodily I. In elaborating both these suggestions, the paper gives particular attention to the connections between motility, continuity, aggression, and creativity in Winnicott's work. PMID:26443951

  13. Tubulin polyglutamylation regulates flagellar motility by controlling a specific inner-arm dynein that interacts with the dynein regulatory complex.

    PubMed

    Kubo, Tomohiro; Yagi, Toshiki; Kamiya, Ritsu

    2012-12-01

    The tpg1 mutant of Chlamydomonas lacks the tubulin polyglutamylase TTLL9 and is deficient in flagellar tubulin polyglutamylation. It exhibits slow swimming, whereas the double mutant with oda2 (a slow-swimming mutant that lacks outer-arm dynein) is completely nonmotile. Thus, tubulin polyglutamylation must be important for the functioning of inner-arm dynein(s). In this study, we show that the tpg1 mutation only slightly affects the motility of mutants that lack dynein "e," one of the seven species of major inner-arm dyneins, whereas it greatly reduces the motility of mutants lacking other inner-arm dynein species. This suggests that dynein e is the main target of motility regulation by tubulin polyglutamylation. Furthermore, the motility of various mutants in the background of the tpg1 mutation raises the possibility that tubulin polyglutamylation also affects the dynein regulatory complex, a dynein e-associated key regulator of flagellar motility, which possibly constitutes the interdoublet (nexin) link. Tubulin polyglutamylation thus may play a central role in the regulation of ciliary and flagellar motility. © 2012 Wiley Periodicals, Inc.

  14. Hydrodynamic Contributions to Amoeboid Cell Motility

    NASA Astrophysics Data System (ADS)

    Lewis, Owen; Guy, Robert

    2012-11-01

    Understanding the methods by which cells move is a fundamental problem in modern biology. Recent evidence has shown that the fluid dynamics of cytoplasm can play a vital role in cellular motility. The slime mold Physarum polycephalum provides an excellent model organism for the study of amoeboid motion. In this research, we use a simply analytic model in conjuction with computational experiments to investigate intracellular fluid flow in a simple model of Physarum. Of particlar interest are stresses generated by cytoplasmic flow which may be used to aid in cellular motility. In our numerical model, the Immersed Boundary Method is used to account for such stresses. We investigate the relationship between contraction waves, flow waves, adhesion, and locomotive forces in an attempt to characterize conditions necessary to generate directed motion.

  15. Hydrodynamic Contributions to Amoeboid Cell Motility

    NASA Astrophysics Data System (ADS)

    Lewis, Owen; Guy, Robert

    2011-11-01

    Understanding the methods by which cells move is a fundamental problem in modern biology. Recent evidence has shown that the fluid dynamics of cytoplasm can play a vital role in cellular motility. The slime mold Physarum polycephalum provides an excellent model organism for the study of amoeboid motion. In this research, we use both analytic and computational models to investigate intracellular fluid flow in a simple model of Physarum. In both models, of we are specifically interested in stresses generated by cytoplasmic flow which act in the direction of cellular motility. In our numerical model, the Immersed Boundary Method is used to account for such stresses. We investigate the relationship between contraction waves, low waves and locomotive forces, and attempt characterize conditions necessary to generate directed motion.

  16. Symbiosis and the origin of eukaryotic motility

    NASA Technical Reports Server (NTRS)

    Margulis, L.; Hinkle, G.

    1991-01-01

    Ongoing work to test the hypothesis of the origin of eukaryotic cell organelles by microbial symbioses is discussed. Because of the widespread acceptance of the serial endosymbiotic theory (SET) of the origin of plastids and mitochondria, the idea of the symbiotic origin of the centrioles and axonemes for spirochete bacteria motility symbiosis was tested. Intracellular microtubular systems are purported to derive from symbiotic associations between ancestral eukaryotic cells and motile bacteria. Four lines of approach to this problem are being pursued: (1) cloning the gene of a tubulin-like protein discovered in Spirocheata bajacaliforniesis; (2) seeking axoneme proteins in spirochets by antibody cross-reaction; (3) attempting to cultivate larger, free-living spirochetes; and (4) studying in detail spirochetes (e.g., Cristispira) symbiotic with marine animals. Other aspects of the investigation are presented.

  17. Soft micromachines with programmable motility and morphology

    NASA Astrophysics Data System (ADS)

    Huang, Hen-Wei; Sakar, Mahmut Selman; Petruska, Andrew J.; Pané, Salvador; Nelson, Bradley J.

    2016-07-01

    Nature provides a wide range of inspiration for building mobile micromachines that can navigate through confined heterogenous environments and perform minimally invasive environmental and biomedical operations. For example, microstructures fabricated in the form of bacterial or eukaryotic flagella can act as artificial microswimmers. Due to limitations in their design and material properties, these simple micromachines lack multifunctionality, effective addressability and manoeuvrability in complex environments. Here we develop an origami-inspired rapid prototyping process for building self-folding, magnetically powered micromachines with complex body plans, reconfigurable shape and controllable motility. Selective reprogramming of the mechanical design and magnetic anisotropy of body parts dynamically modulates the swimming characteristics of the micromachines. We find that tail and body morphologies together determine swimming efficiency and, unlike for rigid swimmers, the choice of magnetic field can subtly change the motility of soft microswimmers.

  18. Automated measurement of cell motility and proliferation

    PubMed Central

    Bahnson, Alfred; Athanassiou, Charalambos; Koebler, Douglas; Qian, Lei; Shun, Tongying; Shields, Donna; Yu, Hui; Wang, Hong; Goff, Julie; Cheng, Tao; Houck, Raymond; Cowsert, Lex

    2005-01-01

    Background Time-lapse microscopic imaging provides a powerful approach for following changes in cell phenotype over time. Visible responses of whole cells can yield insight into functional changes that underlie physiological processes in health and disease. For example, features of cell motility accompany molecular changes that are central to the immune response, to carcinogenesis and metastasis, to wound healing and tissue regeneration, and to the myriad developmental processes that generate an organism. Previously reported image processing methods for motility analysis required custom viewing devices and manual interactions that may introduce bias, that slow throughput, and that constrain the scope of experiments in terms of the number of treatment variables, time period of observation, replication and statistical options. Here we describe a fully automated system in which images are acquired 24/7 from 384 well plates and are automatically processed to yield high-content motility and morphological data. Results We have applied this technology to study the effects of different extracellular matrix compounds on human osteoblast-like cell lines to explore functional changes that may underlie processes involved in bone formation and maintenance. We show dose-response and kinetic data for induction of increased motility by laminin and collagen type I without significant effects on growth rate. Differential motility response was evident within 4 hours of plating cells; long-term responses differed depending upon cell type and surface coating. Average velocities were increased approximately 0.1 um/min by ten-fold increases in laminin coating concentration in some cases. Comparison with manual tracking demonstrated the accuracy of the automated method and highlighted the comparative imprecision of human tracking for analysis of cell motility data. Quality statistics are reported that associate with stage noise, interference by non-cell objects, and uncertainty in the

  19. Soft micromachines with programmable motility and morphology.

    PubMed

    Huang, Hen-Wei; Sakar, Mahmut Selman; Petruska, Andrew J; Pané, Salvador; Nelson, Bradley J

    2016-01-01

    Nature provides a wide range of inspiration for building mobile micromachines that can navigate through confined heterogenous environments and perform minimally invasive environmental and biomedical operations. For example, microstructures fabricated in the form of bacterial or eukaryotic flagella can act as artificial microswimmers. Due to limitations in their design and material properties, these simple micromachines lack multifunctionality, effective addressability and manoeuvrability in complex environments. Here we develop an origami-inspired rapid prototyping process for building self-folding, magnetically powered micromachines with complex body plans, reconfigurable shape and controllable motility. Selective reprogramming of the mechanical design and magnetic anisotropy of body parts dynamically modulates the swimming characteristics of the micromachines. We find that tail and body morphologies together determine swimming efficiency and, unlike for rigid swimmers, the choice of magnetic field can subtly change the motility of soft microswimmers. PMID:27447088

  20. Hydroxyapatite motility implants in ocular prosthetics.

    PubMed

    Cowper, T R

    1995-03-01

    For the past 5 years, an increasing number of ophthalmologists have been using hydroxyapatite (HA) motility implants after uncomplicated enucleation or evisceration of the eye. Unlike previous implant materials, HA promotes fibrovascular ingrowth and seemingly true integration of the motility implant to the residual ocular structures. As a result, a more stable defect and greater movement of the overlying prosthesis is produced. In addition, the problems of long-term orbital implant migration and the vexing postenucleation socket syndrome are thought to be minimized. This article briefly reviews the history and development of orbital implants and HA implant surgical and prosthetic procedures. It is concluded that HA implant rehabilitation is indicated after most uncomplicated enucleations or eviscerations where there is small likelihood of complication.

  1. [Gastrointestinal motility and possibilities of influencing it].

    PubMed

    Duris, I; Payer, J; Huorka, M; Randus, V; Ondrejka, P

    1994-06-01

    The authors discuss factors which influence the motility of the smooth muscles in the pancreatobiliary region. They investigated some clinical and laboratory parameters after administration of the selective antagonist of calcium influx-Pineverium bromide-Dicetel. The drug influenced significantly in a positive way nausea, flatulence, pain and chronically elevated amylases. The authors mention a cycle of possible neurohumoral changes with which specific calcium channel antagonists could interfere. PMID:8073641

  2. Travel stress alters the intestinal migrating myoelectric complex in rats: antagonist effect of trimebutine.

    PubMed

    Diop, L; Pascaud, X; Le Gallou, B; Junien, J L

    1992-01-01

    A novel stress model was developed that may closely resemble a real-life situation. Intestinal motility was monitored in rats before and after a 12 hour train voyage (travel stress). Travel stress reduced the duration of phase III of the intestinal MMC by 30% (3.2 +/- 0.3 vs 4.7 +/- 0.6 min; p less than 0.001) while the durations of phase I and II were unaffected. This effect persisted for two days. Phase III duration returned to basal values after 3 days indicating a reversible alteration on intestinal migrating myoelectric complex (MMC). The infusion of trimebutine at a flow rate of 166 micrograms/kg/h during the stress exposure abolished the changes observed in the duration of phase III of the MMC; the infusion of diazepam (16.6 micrograms/kg/h) had no effect. These results indicate that the travel stress model may be similar to common life events that induce alterations of intestinal motility. Furthermore, trimebutine prevented the reduction of phase III duration induced by travel stress suggesting its possible action on mechanisms involved in the mediation of the stress-induced intestinal motility changes. PMID:1732698

  3. Characterization of swarming motility in Citrobacter freundii.

    PubMed

    Cong, Yanguang; Wang, Jing; Chen, Zhijin; Xiong, Kun; Xu, Qiwang; Hu, Fuquan

    2011-04-01

    Bacterial swarming motility is a flagella-dependent translocation on the surface environment. It has received extensive attention as a population behavior involving numerous genes. Here, we report that Citrobacter freundii, an opportunistic pathogen, exhibits swarming movement on a solid medium surface with appropriate agar concentration. The swarming behavior of C. freundii was described in detail. Insertional mutagenesis with transposon Mini-Tn5 was carried out to discover genetic determinants related to the swarming of C. freundii. A number of swarming genes were identified, among which flhD, motA, motB, wzx, rfaL, rfaJ, rfbX, rfaG, rcsD, rcsC, gshB, fabF, dam, pgi, and rssB have been characterized previously in other species. In mutants related to lipopolysaccharide synthesis and RcsCDB signal system, a propensity to form poorly motile bacterial aggregates on the agar surface was observed. The aggregates hampered bacterial surface migration. In several mutants, the insertion sites were identified to be in the ORF of yqhC, yeeZ, CKO_03941, glgC, and ttrA, which have never been shown to be involved in swarming. Our results revealed several novel characteristics of swarming motility in C. freundii which are worthy of further study.

  4. Hyaluronan stimulates pancreatic cancer cell motility

    PubMed Central

    Cheng, Xiao-Bo; Kohi, Shiro; Koga, Atsuhiro; Hirata, Keiji; Sato, Norihiro

    2016-01-01

    Hyaluronan (HA) accumulates in pancreatic ductal adenocarcinoma (PDAC), but functional significance of HA in the aggressive phenotype remains unknown. We used different models to investigate the effect of HA on PDAC cell motility by wound healing and transwell migration assay. Changes in cell motility were examined in 8 PDAC cell lines in response to inhibition of HA production by treatment with 4-methylumbelliferone (4-MU) and to promotion by treatment with 12-O-tetradecanoyl-phorbol-13-acetate (TPA) or by co-culture with tumor-derived stromal fibroblasts. We also investigated changes in cell motility by adding exogenous HA. Additionally, mRNA expressions of hyaluronan synthases and hyaluronidases were examined using real time RT-PCR. Inhibition of HA by 4-MU significantly decreased the migration, whereas promotion of HA by TPA or co-culture with tumor-derived fibroblasts significantly increased the migration of PDAC cells. The changes in HA production by these treatments tended to be associated with changes in HAS3 mRNA expression. Furthermore, addition of exogenous HA, especially low-molecular-weight HA, significantly increased the migration of PDAC cells. These findings suggest that HA stimulates PDAC cell migration and thus represents an ideal therapeutic target to prevent invasion and metastasis. PMID:26684359

  5. Effect of total laryngectomy on esophageal motility

    SciTech Connect

    Hanks, J.B.; Fisher, S.R.; Meyers, W.C.; Christian, K.C.; Postlethwait, R.W.; Jones, R.S.

    1981-01-01

    Total laryngectomy for cancer can result in dysphagia and altered esophageal motility. Manometric changes in the upper esophageal sphincter (UES), and in proximal and distal esophageal function have been reported. However, most studies have failed to take into account radiation therapy and appropriate controls. We selected ten male patients (54.3 +/- 1.9 yr) for longitudinal manometric evaluation prior to laryngectomy then at two weeks and again six months later. No patient received preoperative radiation therapy, had a previous history of esophageal surgery, or developed a postoperative wound infection or fistula. Seven of ten patients had positive nodes and received 6,000-6,600 rads postoperative radiation therapy. Preoperatively 4 of 10 patients complained of dysphagia which did not significantly change following surgery and radiation. Two of three patients who did not complain of dysphagia preoperatively and received radiation postoperatively developed dysphagia. No patient without dysphagia preoperatively who received no radiation therapy developed symptoms. Our studies show that laryngectomy causes alterations in the UES resting and peak pressures but not in the proximal or distal esophagus, or the lower esophageal sphincter. These data also imply radiation therapy may be associated with progressive alterations in motility and symptomatology. Further study regarding the effects of radiation on esophageal motility and function are urged.

  6. Swimming Motility Reduces Deposition to Silica Surfaces

    SciTech Connect

    Lu, Nanxi; Massoudieh, Arash; Liang, Xiaomeng; Hu, Dehong; Kamai, Tamir; Ginn, Timothy R.; Zilles, Julie L.; Nguyen, Thanh H.

    2015-01-01

    The role of swimming motility on bacterial transport and fate in porous media was evaluated. We present microscopic evidence showing that strong swimming motility reduces attachment of Azotobacter vinelandii cells to silica surfaces. Applying global and cluster statistical analyses to microscopic videos taken under non-flow conditions, wild type, flagellated A. vinelandii strain DJ showed strong swimming ability with an average speed of 13.1 μm/s, DJ77 showed impaired swimming averaged at 8.7 μm/s, and both the non-flagellated JZ52 and chemically treated DJ cells were non-motile. Quantitative analyses of trajectories observed at different distances above the collector of a radial stagnation point flow cell (RSPF) revealed that both swimming and non-swimming cells moved with the flow when at a distance of at least 20 μm from the collector surface. Near the surface, DJ cells showed both horizontal and vertical movement diverging them from reaching surfaces, while chemically treated DJ cells moved with the flow to reach surfaces, suggesting that strong swimming reduced attachment. In agreement with the RSPF results, the deposition rates obtained for two-dimensional multiple-collector micromodels were also lowest for DJ, while DJ77 and JZ52 showed similar values. Strong swimming specifically reduced deposition on the upstream surfaces of the micromodel collectors.

  7. Vertebrate Intestinal Endoderm Development

    PubMed Central

    Spence, Jason R.; Lauf, Ryan; Shroyer, Noah F.

    2010-01-01

    The endoderm gives rise to the lining of the esophagus, stomach and intestines, as well as associated organs. To generate a functional intestine, a series of highly orchestrated developmental processes must occur. In this review, we attempt to cover major events during intestinal development from gastrulation to birth, including endoderm formation, gut tube growth and patterning, intestinal morphogenesis, epithelial reorganization, villus emergence as well as proliferation and cytodifferentiation. Our discussion includes morphological and anatomical changes during intestinal development as well as molecular mechanisms regulating these processes. PMID:21246663

  8. Circadian regulators of intestinal lipid absorption.

    PubMed

    Hussain, M Mahmood; Pan, Xiaoyue

    2015-04-01

    Among all the metabolites present in the plasma, lipids, mainly triacylglycerol and diacylglycerol, show extensive circadian rhythms. These lipids are transported in the plasma as part of lipoproteins. Lipoproteins are synthesized primarily in the liver and intestine and their production exhibits circadian rhythmicity. Studies have shown that various proteins involved in lipid absorption and lipoprotein biosynthesis show circadian expression. Further, intestinal epithelial cells express circadian clock genes and these genes might control circadian expression of different proteins involved in intestinal lipid absorption. Intestinal circadian clock genes are synchronized by signals emanating from the suprachiasmatic nuclei that constitute a master clock and from signals coming from other environmental factors, such as food availability. Disruptions in central clock, as happens due to disruptions in the sleep/wake cycle, affect intestinal function. Similarly, irregularities in temporal food intake affect intestinal function. These changes predispose individuals to various metabolic disorders, such as metabolic syndrome, obesity, diabetes, and atherosclerosis. Here, we summarize how circadian rhythms regulate microsomal triglyceride transfer protein, apoAIV, and nocturnin to affect diurnal regulation of lipid absorption.

  9. Receptor tyrosine and MAP kinase are involved in effects of H(2)O(2) on interstitial cells of Cajal in murine intestine.

    PubMed

    Choi, Seok; Yeum, Cheol Ho; Kim, Young Dae; Park, Chan Guk; Kim, Man Yoo; Park, Jong-Seong; Jeong, Han-Seong; Kim, Byung Joo; So, Insuk; Kim, Ki Whan

    2010-01-01

    Hydrogen peroxide (H(2)O(2)) is involved in intestinal motility through changes of smooth muscle activity. However, there is no report as to the modulatory effects of H(2)O(2) on interstitial cells of Cajal (ICC). We investigated the H(2)O(2) effects and signal transductions to determine whether the intestinal motility can be modulated through ICC. We performed whole-cell patch clamp in cultured ICC from murine intestine and molecular analyses. H(2)O(2) hyperpolarized the membrane and inhibited pacemaker currents. These effects were inhibited by glibenclamide, an inhibitor of ATP-sensitive K+ (K(ATP)) channels. The free-radical scavenger catalase inhibited the H(2)O(2)-induced effects. MAFP and AACOCF3 (a cytosolic phospholipase A2 inhibitors) or SC-560 and NS-398 (a selective COX-1 and 2 inhibitor) or AH6809 (an EP2 receptor antagonist) inhibited the H(2)O(2)-induced effects. PD98059 (a mitogen activated/ERK-activating protein kinase inhibitor) inhibited the H(2)O(2)-induced effects, though SB-203580 (a p38 MAPK inhibitor) or a JNK inhibitor did not affect. H(2)O(2)-induced effects could not be inhibited by LY-294002 (an inhibitor of PI3-kinases), calphostin C (a protein kinase C inhibitor) or SQ-22536 (an adenylate cyclase inhibitor). Adenoviral infection analysis revealed H2O2 stimulated tyrosine kinase activity and AG 1478 (an antagonist of epidermal growth factor receptor tyrosine kinase) inhibited the H(2)O(2)-induced effects. These results suggest H(2)O(2) can modulate ICC pacemaker activity and this occur by the activation of K(ATP) channels through PGE(2) production via receptor tyrosine kinase-dependent MAP kinase activation.

  10. Establishment of Intestinal Bacteriology

    PubMed Central

    MITSUOKA, Tomotari

    2014-01-01

    Research on intestinal bacteria began around the end of the 19th century. During the last 5 decades of the 20th century, research on the intestinal microbiota made rapid progress. At first, in my work, I first developed a method of comprehensive analysis of the intestinal microbiota, and then I established classification and identification methods for intestinal anaerobes. Using these methods I discovered a number of ecological rules governing the intestinal microbiota and the role of the intestinl microbiota in health and disease. Moreover, using germfree animals, it was proven that the intestinal microbiota has a role in carcinogenesis and aging in the host. Thus, a new interdisciplinary field, “intestinal bacteriology” was established. PMID:25032084

  11. AM841, a covalent cannabinoid ligand, powerfully slows gastrointestinal motility in normal and stressed mice in a peripherally restricted manner

    PubMed Central

    Keenan, C M; Storr, M A; Thakur, G A; Wood, J T; Wager-Miller, J; Straiker, A; Eno, M R; Nikas, S P; Bashashati, M; Hu, H; Mackie, K; Makriyannis, A; Sharkey, K A

    2015-01-01

    Background and Purpose Cannabinoid (CB) ligands have been demonstrated to have utility as novel therapeutic agents for the treatment of pain, metabolic conditions and gastrointestinal (GI) disorders. However, many of these ligands are centrally active, which limits their usefulness. Here, we examine a unique novel covalent CB receptor ligand, AM841, to assess its potential for use in physiological and pathophysiological in vivo studies. Experimental Approach The covalent nature of AM841 was determined in vitro using electrophysiological and receptor internalization studies on isolated cultured hippocampal neurons. Mouse models were used for behavioural analysis of analgesia, hypothermia and hypolocomotion. The motility of the small and large intestine was assessed in vivo under normal conditions and after acute stress. The brain penetration of AM841 was also determined. Key Results AM841 behaved as an irreversible CB1 receptor agonist in vitro. AM841 potently reduced GI motility through an action on CB1 receptors in the small and large intestine under physiological conditions. AM841 was even more potent under conditions of acute stress and was shown to normalize accelerated GI motility under these conditions. This compound behaved as a peripherally restricted ligand, showing very little brain penetration and no characteristic centrally mediated CB1 receptor-mediated effects (analgesia, hypothermia or hypolocomotion). Conclusions and Implications AM841, a novel peripherally restricted covalent CB1 receptor ligand that was shown to be remarkably potent, represents a new class of potential therapeutic agents for the treatment of functional GI disorders. PMID:25572435

  12. Normal and abnormal electrical propagation in the small intestine.

    PubMed

    Lammers, W J E P

    2015-02-01

    As in other muscular organs, small intestinal motility is determined to a large degree by the electrical activities that occur in the smooth muscle layers of the small intestine. In recent decades, the interstitial cells of Cajal, located in the myenteric plexus, have been shown to be responsible for the generation and propagation of the electrical impulse: the slow wave. It was also known that the slow waves as such do not cause contraction, but that the action potentials ('spikes') that are generated by the slow waves are responsible for the contractions. Recording from large number of extracellular electrodes simultaneously is one method to determine origin and pattern of propagation of these electrical signals. This review reports the characteristics of slow wave propagation through the intestinal tube, the occurrence of propagation blocks along its length, which explains the well-known decrease in frequency, and the specific propagation pattern of the spikes that follow the slow waves. But the value of high-resolution mapping is highest in discovering and analysing mechanisms of arrhythmias in the gut. Most recently, circus movements (also called 're-entries') have been described in the small intestine in several species. Moreover, several types of re-entries have now been described, some similar to what may occur in the heart, such as functional re-entries, but others more unique to the small intestine, such as circumferential re-entry. These findings seem to suggest the possibilities of hitherto unknown pathologies that may be present in the small intestine.

  13. Physics of protein motility and motor proteins

    NASA Astrophysics Data System (ADS)

    Kolomeisky, Anatoly B.

    2013-09-01

    Motor proteins are enzymatic molecules that transform chemical energy into mechanical motion and work. They are critically important for supporting various cellular activities and functions. In the last 15 years significant progress in understanding the functioning of motor proteins has been achieved due to revolutionary breakthroughs in single-molecule experimental techniques and strong advances in theoretical modelling. However, microscopic mechanisms of protein motility are still not well explained, and the collective efforts of many scientists are needed in order to solve these complex problems. In this special section the reader will find the latest advances on the difficult road to mapping motor proteins dynamics in various systems. Recent experimental developments have allowed researchers to monitor and to influence the activity of single motor proteins with a high spatial and temporal resolution. It has stimulated significant theoretical efforts to understand the non-equilibrium nature of protein motility phenomena. The latest results from all these advances are presented and discussed in this special section. We would like to thank the scientists from all over the world who have reported their latest research results for this special section. We are also grateful to the staff and editors of Journal of Physics: Condensed Matter for their invaluable help in handling all the administrative and refereeing activities. The field of motor proteins and protein motility is fast moving, and we hope that this collection of articles will be a useful source of information in this highly interdisciplinary area. Physics of protein motility and motor proteins contents Physics of protein motility and motor proteinsAnatoly B Kolomeisky Identification of unique interactions between the flexible linker and the RecA-like domains of DEAD-box helicase Mss116 Yuan Zhang, Mirkó Palla, Andrew Sun and Jung-Chi Liao The load dependence of the physical properties of a molecular motor

  14. Kinins as mediators of intestinal secretion.

    PubMed

    Gaginella, T S; Kachur, J F

    1989-01-01

    Kinins are small peptides that have diverse biological actions. Concentrations of kinins in the nanomolar or subnanomolar range induce intestinal smooth muscle contraction and evoke mucosal electrolyte secretion. Hyperkininemia is associated with effects on gastrointestinal motility and intestinal mucosal inflammation. Bradykinin and kallidin are the predominant kinins with effects on the gastrointestinal tract of mammals. Bradykinin stimulates chloride ion secretion by the guinea pig and rabbit ileum, rabbit colon, rat colon and monolayers of human HCA-7 cells. Kinins directly or indirectly stimulate phospholipase A2 and phospholipase C. Cells in the lamina propria of the mucosa (e.g., fibroblasts, mast cells, leukocytes), by liberating cyclooxygenase and lipoxygenase metabolites of arachidonic acid, are involved in the kinin response; direct effects on epithelial cells cannot be ruled out, however. Antagonists now exist for kinin receptors. Based on studies with these antagonists in smooth muscle preparations, two subgroups of kinin receptor have been identified. The B2-type receptor appears to be responsible for both the contraction of ileal muscle and ileal secretion. Kinins are probably more important as pathophysiological rather than as physiological mediators. They may amplify the effect of inflammatory products that induce intestinal secretion. The precise involvement of kinins in clinical mucosal secretory states and diarrhea will require quantitative assessment of their levels during each phase of mucosal inflammation. Additional studies on the mechanism of action of kinins will be essential in designing therapy to mitigate the symptoms associated with mucosal inflammation.

  15. Knockdown of Inner Arm Protein IC138 in Trypanosoma brucei Causes Defective Motility and Flagellar Detachment

    PubMed Central

    Wilson, Corinne S.; Chang, Alex J.; Greene, Rebecca; Machado, Sulynn; Parsons, Matthew W.; Takats, Taylor A.; Zambetti, Luke J.; Springer, Amy L.

    2015-01-01

    Motility in the protozoan parasite Trypanosoma brucei is conferred by a single flagellum, attached alongside the cell, which moves the cell forward using a beat that is generated from tip-to-base. We are interested in characterizing components that regulate flagellar beating, in this study we extend the characterization of TbIC138, the ortholog of a dynein intermediate chain that regulates axonemal inner arm dynein f/I1. TbIC138 was tagged In situ-and shown to fractionate with the inner arm components of the flagellum. RNAi knockdown of TbIC138 resulted in significantly reduced protein levels, mild growth defect and significant motility defects. These cells tended to cluster, exhibited slow and abnormal motility and some cells had partially or fully detached flagella. Slight but significant increases were observed in the incidence of mis-localized or missing kinetoplasts. To document development of the TbIC138 knockdown phenotype over time, we performed a detailed analysis of flagellar detachment and motility changes over 108 hours following induction of RNAi. Abnormal motility, such as slow twitching or irregular beating, was observed early, and became progressively more severe such that by 72 hours-post-induction, approximately 80% of the cells were immotile. Progressively more cells exhibited flagellar detachment over time, but this phenotype was not as prevalent as immotility, affecting less than 60% of the population. Detached flagella had abnormal beating, but abnormal beating was also observed in cells with no flagellar detachment, suggesting that TbIC138 has a direct, or primary, effect on the flagellar beat, whereas detachment is a secondary phenotype of TbIC138 knockdown. Our results are consistent with the role of TbIC138 as a regulator of motility, and has a phenotype amenable to more extensive structure-function analyses to further elucidate its role in the control of flagellar beat in T. brucei. PMID:26555902

  16. Effect of Daily Supine LBNP Exercise on Gastrointestinal Motility During Antiorthostatic Bedrest in Normal Subjects

    NASA Technical Reports Server (NTRS)

    Putcha, Lakshmi; DeKerlegand, D.; Hargens, Alan R. (Technical Monitor)

    1997-01-01

    Space flight alters gastrointestinal (GI) function in general, and GI motility, in particular. This can decrease appetite, affect the body's ability to absorb nutrients, fluids and electrolytes, and contribute to a negative energy balance. Antiorthostatic bed rest (ABR) has been used to simulate microgravity-induced physiological changes in human subjects. The objective of this investigation is to determine if daily supine lower body negative pressure (LBNP) exercise will maintain GI motility at near normal levels during ABR. Eight subjects participated in the study protocol consisting of an ambulatory phase scheduled before bedrest periods and two 14 day bed rest (6 deg head-down tilt) periods, once with and another time without exercise. Supine treadmill running in an LBNP chamber was used for exercise. Mouth-to-cecum transit time (MCTT) of lactulose was measured indirectly using the rise in breath hydrogen level after oral administration of lactulose (20 g) following a standard low-fiber breakfast. GI motility during ambulatory and ABR periods was assessed using MCTT data. Results of this Study indicate that GI motility during ABR without exercise decreased by 45% [MCTT +/- S.E.M. 56.2 +/- 6.0 (Ambulatory); 87.3 +/- 8.3 (ABR)]. Supine LBNP exercise did not significantly alter this reduction in GI motility during ABR [MCTT +/- S.E.M. 81.3 +/- 4.2 (Exercise); 87.3 +/- 8.3 (No Exercise)]. These results suggest that supine LBNP exercise may not be an effective countermeasure for microgravity-induced decrements in GI motility and function.

  17. Energetic Metabolism and Human Sperm Motility: Impact of CB1 Receptor Activation

    PubMed Central

    Barbonetti, A.; Vassallo, M. R. C.; Fortunato, D.; Francavilla, S.; Maccarrone, M.; Francavilla, F.

    2010-01-01

    It has been reported that the endocannabinoid anandamide (AEA) exerts an adverse effect on human sperm motility, which has been ascribed to inhibition of mitochondrial activity. This seems to be at variance with evidence suggesting a major role of glycolysis in supplying ATP for sperm motility; furthermore, the role of AEA-binding receptors in mediating mitochondrial inhibition has not yet been explored. In this study, human sperm exposure to Met-AEA (methanandamide, nonhydrolyzable analog of AEA) in the micromolar range significantly decreased mitochondrial transmembrane potential (ΔΨm), similarly to rotenone, mitochondrial complex I inhibitor. The effect of Met-AEA (1 μm) was prevented by SR141716, CB1 cannabinoid receptor antagonist, but not by SR144528, CB2 antagonist, nor by iodoresiniferatoxin, vanilloid receptor antagonist. The effect of Met-AEA did not involve activation of caspase-9 or caspase-3 and was reverted by washing. In the presence of glucose, sperm exposure either to Met-AEA up to 1 μm or to rotenone for up to 18 h did not affect sperm motility. At higher doses Met-AEA produced a CB1-independent poisoning of spermatozoa, reducing their viability. Under glycolysis blockage, 1 μm Met-AEA, similarly to rotenone, dramatically abolished sperm motility, an effect that was prevented by SR1 and reverted by washing. In conclusion, CB1 activation induced a nonapoptotic decrease of ΔΨm, the detrimental reflection on sperm motility of which could be revealed only under glycolysis blockage, unless very high doses of Met-AEA, producing CB1-independent sperm toxicity, were used. The effects of CB1 activation reported here contribute to elucidate the relationship between energetic metabolism and human sperm motility. PMID:20962050

  18. Knockdown of Inner Arm Protein IC138 in Trypanosoma brucei Causes Defective Motility and Flagellar Detachment.

    PubMed

    Wilson, Corinne S; Chang, Alex J; Greene, Rebecca; Machado, Sulynn; Parsons, Matthew W; Takats, Taylor A; Zambetti, Luke J; Springer, Amy L

    2015-01-01

    Motility in the protozoan parasite Trypanosoma brucei is conferred by a single flagellum, attached alongside the cell, which moves the cell forward using a beat that is generated from tip-to-base. We are interested in characterizing components that regulate flagellar beating, in this study we extend the characterization of TbIC138, the ortholog of a dynein intermediate chain that regulates axonemal inner arm dynein f/I1. TbIC138 was tagged In situ-and shown to fractionate with the inner arm components of the flagellum. RNAi knockdown of TbIC138 resulted in significantly reduced protein levels, mild growth defect and significant motility defects. These cells tended to cluster, exhibited slow and abnormal motility and some cells had partially or fully detached flagella. Slight but significant increases were observed in the incidence of mis-localized or missing kinetoplasts. To document development of the TbIC138 knockdown phenotype over time, we performed a detailed analysis of flagellar detachment and motility changes over 108 hours following induction of RNAi. Abnormal motility, such as slow twitching or irregular beating, was observed early, and became progressively more severe such that by 72 hours-post-induction, approximately 80% of the cells were immotile. Progressively more cells exhibited flagellar detachment over time, but this phenotype was not as prevalent as immotility, affecting less than 60% of the population. Detached flagella had abnormal beating, but abnormal beating was also observed in cells with no flagellar detachment, suggesting that TbIC138 has a direct, or primary, effect on the flagellar beat, whereas detachment is a secondary phenotype of TbIC138 knockdown. Our results are consistent with the role of TbIC138 as a regulator of motility, and has a phenotype amenable to more extensive structure-function analyses to further elucidate its role in the control of flagellar beat in T. brucei. PMID:26555902

  19. Automated analysis of rabbit sperm motility and the effect of chemicals on sperm motion parameters.

    PubMed

    Young, R J; Bodt, B A; Iturralde, T G; Starke, W C

    1992-11-01

    Appropriate software settings and optimum procedures were determined for the measurement of the motion parameters of rabbit spermatozoa by the CellSoft (Cryo Resources Ltd., Montgomery, NY) computer-assisted digital image analysis system. The system was used to follow motion parameter changes occurring in spermatozoa incubated for 6 hr with or without exposure to chemicals. Mean amplitude of lateral head displacement (AALH) increased over the 6 hr period, while curvilinear velocity (Vc) first increased and then decreased. Values for linearity (Lin), or beat cross frequency (BCF), were unchanged. The majority of spermatozoa progressed linearly, with rapid rotation of the sperm head, but subpopulations of spermatozoa with different swimming patterns appeared after 1-3 hr of incubation. Percentage motile sperm and Vc were most sensitive to the action of the compounds (pyrogallol, hydroquinone, ammonium oxalate, triethyl phosphite, and pinocolyl alcohol), while BCF was least affected. The decline in percentage of motile sperm was dependent on duration of exposure and chemical concentration. Mean Vc of the sperm population decreased rapidly upon chemical exposure and remained at a low value until motility ceased. The initial decrease in Vc was dependent on the concentration of the added compound. Motion-based indices--motility concentration (MCI50), motility time (MTI50), and velocity (VI)--were defined and used as toxicological endpoints. The rank order of these indices, the end point of the neutral red in vitro assay for cytotoxicity, and LD50 values for the five compounds were the same, suggesting that chemical inhibition of sperm motility may be useful as a method for the in vitro assessment of chemical cytotoxicity.

  20. Polarized cell motility induces hydrogen peroxide to inhibit cofilin via cysteine oxidation.

    PubMed

    Cameron, Jenifer M; Gabrielsen, Mads; Chim, Ya Hua; Munro, June; McGhee, Ewan J; Sumpton, David; Eaton, Philip; Anderson, Kurt I; Yin, Huabing; Olson, Michael F

    2015-06-01

    Mesenchymal cell motility is driven by polarized actin polymerization [1]. Signals at the leading edge recruit actin polymerization machinery to promote membrane protrusion, while matrix adhesion generates tractive force to propel forward movement. To work effectively, cell motility is regulated by a complex network of signaling events that affect protein activity and localization. H2O2 has an important role as a diffusible second messenger [2], and mediates its effects through oxidation of cysteine thiols. One cell activity influenced by H2O2 is motility [3]. However, a lack of sensitive and H2O2-specific probes for measurements in live cells has not allowed for direct observation of H2O2 accumulation in migrating cells or protrusions. In addition, the identities of proteins oxidized by H2O2 that contribute to actin dynamics and cell motility have not been characterized. We now show, as determined by fluorescence lifetime imaging microscopy, that motile cells generate H2O2 at membranes and cell protrusions and that H2O2 inhibits cofilin activity through oxidation of cysteines 139 (C139) and 147 (C147). Molecular modeling suggests that C139 oxidation would sterically hinder actin association, while the increased negative charge of oxidized C147 would lead to electrostatic repulsion of the opposite negatively charged surface. Expression of oxidation-resistant cofilin impairs cell spreading, adhesion, and directional migration. These findings indicate that H2O2 production contributes to polarized cell motility through localized cofilin inhibition and that there are additional proteins oxidized during cell migration that might have similar roles.

  1. Membrane tension feedback on shape and motility of eukaryotic cells

    NASA Astrophysics Data System (ADS)

    Winkler, Benjamin; Aranson, Igor S.; Ziebert, Falko

    2016-04-01

    In the framework of a phase field model of a single cell crawling on a substrate, we investigate how the properties of the cell membrane affect the shape and motility of the cell. Since the membrane influences the cell dynamics on multiple levels and provides a nontrivial feedback, we consider the following fundamental interactions: (i) the reduction of the actin polymerization rate by membrane tension; (ii) area conservation of the cell's two-dimensional cross-section vs. conservation of the circumference (i.e. membrane inextensibility); and (iii) the contribution from the membrane's bending energy to the shape and integrity of the cell. As in experiments, we investigate two pertinent observables - the cell's velocity and its aspect ratio. We find that the most important effect is the feedback of membrane tension on the actin polymerization. Bending rigidity has only minor effects, visible mostly in dynamic reshaping events, as exemplified by collisions of the cell with an obstacle.

  2. Src family kinases differentially influence glioma growth and motility.

    PubMed

    Lewis-Tuffin, Laura J; Feathers, Ryan; Hari, Priya; Durand, Nisha; Li, Zhimin; Rodriguez, Fausto J; Bakken, Katie; Carlson, Brett; Schroeder, Mark; Sarkaria, Jann N; Anastasiadis, Panos Z

    2015-11-01

    Src-family kinase (SFK) signaling impacts multiple tumor-related properties, particularly in the context of the brain tumor glioblastoma. Consequently, the pan-SFK inhibitor dasatinib has emerged as a therapeutic strategy, despite physiologic limitations to its effectiveness in the brain. We investigated the importance of individual SFKs (Src, Fyn, Yes, and Lyn) to glioma tumor biology by knocking down individual SFK expression both in culture (LN229, SF767, GBM8) and orthotopic xenograft (GBM8) contexts. We evaluated the effects of these knockdowns on tumor cell proliferation, migration, and motility-related signaling in culture, as well as overall survival in the orthotopic xenograft model. The four SFKs differed significantly in their importance to these properties. In culture, Src, Fyn, and Yes knockdown generally reduced growth and migration and altered motility-related phosphorylation patterns while Lyn knockdown did so to a lesser extent. However the details of these effects varied significantly depending on the cell line: in no case were conclusions about the role of a particular SFK applicable to all of the measures or all of the cell types examined. In the orthotopic xenograft model, mice implanted with non-target or Src or Fyn knockdown cells showed no differences in survival. In contrast, mice implanted with Yes knockdown cells had longer survival, associated with reduced tumor cell proliferation. Those implanted with Lyn knockdown cells had shorter survival, associated with higher overall tumor burden. Together, our results suggest that Yes signaling directly affects tumor cell biology in a pro-tumorigenic manner, while Lyn signaling affects interactions between tumor cells and the microenvironment in an anti-tumor manner. In the context of therapeutic targeting of SFKs, these results suggest that pan-SFK inhibitors may not produce the intended therapeutic benefit when Lyn is present. PMID:26105207

  3. Effect of semen preparation on casa motility results in cryopreserved bull spermatozoa.

    PubMed

    Contri, Alberto; Valorz, Claudio; Faustini, Massimo; Wegher, Laura; Carluccio, Augusto

    2010-08-01

    Computer-assisted sperm analyzers (CASA) have become the standard tool for evaluating sperm motility and kinetic patterns because they provide objective data for thousands of sperm tracks. However, these devices are not ready-to-use and standardization of analytical practices is a fundamental requirement. In this study, we evaluated the effects of some settings, such as frame rate and frames per field, chamber and time of analysis, and samples preparations, including thawing temperature, sperm sample concentration, and media used for dilution, on the kinetic results of bovine frozen-thawed semen using a CASA. In Experiment 1, the frame rate (30-60 frame/s) significantly affected motility parameters, whereas the number of frames per field (30 or 45) did not seem to affect sperm kinetics. In Experiment 2, the thawing protocol affects sperm motility and kinetic parameters. Sperm sample concentration significantly limited the opportunity to perform the analysis and the kinetic results. A concentration of 100 and 50 x 10(6) sperm/mL limited the device's ability to perform the analysis or gave wrong results, whereas 5, 10, 20, and 30 x 10(6) sperm/mL concentrations allowed the analysis to be performed, but with different results (Experiment 3). The medium used for the dilution of the sample, which is fundamental for a correct sperm head detection, affects sperm motility results (Experiment 4). In this study, Makler and Leja chambers were used to perform the semen analysis with CASA devices. The chamber used significantly affected motility results (Experiment 5). The time between chamber loading and analysis affected sperm velocities, regardless of chamber used. Based on results recorded in this study, we propose that the CASA evaluation of motility of bovine frozen-thawed semen using Hamilton-Thorne IVOS 12.3 should be performed using a frame rate of 60 frame/s and 30 frames per field. Semen should be diluted at least at 20 x 10(6) sperm/mL using PBS. Furthermore, it is

  4. Constitutively Active 5-HT Receptors: An Explanation of How 5-HT Antagonists Inhibit Gut Motility in Species Where 5-HT is Not an Enteric Neurotransmitter?

    PubMed Central

    Spencer, Nick J.

    2015-01-01

    Antagonists of 5-Hydroxytryptamine (5-HT) receptors are well known to inhibit gastrointestinal (GI)-motility and transit in a variety of mammals, including humans. Originally, these observations had been interpreted by many investigators (including us) as evidence that endogenous 5-HT plays a major role in GI motility. This seemed a logical assumption. However, the story changed dramatically after recent studies revealed that 5-HT antagonists still blocked major GI motility patterns (peristalsis and colonic migrating motor complexes) in segments of intestine depleted of all 5-HT. Then, these results were further supported by Dr. Gershons' laboratory, which showed that genetic deletion of all genes that synthesizes 5-HT had minor, or no inhibitory effects on GI transit in vivo. If 5-HT was essential for GI motility patterns and transit, then one would expect major disruptions in motility and transit when 5-HT synthesis was genetically ablated. This does not occur. The inhibitory effects of 5-HT antagonists on GI motility clearly occur independently of any 5-HT in the gut. Evidence now suggests that 5-HT antagonists act on 5-HT receptors in the gut which are constitutively active, and don't require 5-HT for their activation. This would explain a long-standing mystery of how 5-HT antagonists inhibit gut motility in species like mice, rats, and humans where 5-HT is not an enteric neurotransmitter. Studies are now increasingly demonstrating that the presence of a neurochemical in enteric neurons does not mean they function as neurotransmitters. Caution should be exercised when interpreting any inhibitory effects of 5-HT antagonists on GI motility. PMID:26732863

  5. Exploring food effects on indinavir absorption with human intestinal fluids in the mouse intestine.

    PubMed

    Holmstock, Nico; De Bruyn, Tom; Bevernage, Jan; Annaert, Pieter; Mols, Raf; Tack, Jan; Augustijns, Patrick

    2013-04-11

    Food can have a significant impact on the pharmacokinetics of orally administered drugs, as it may affect drug solubility as well as permeability. Since fed state conditions cannot easily be implemented in the presently available permeability tools, including the frequently used Caco-2 system, exploring food effects during drug development can be quite challenging. In this study, we investigated the effect of fasted and fed state conditions on the intestinal absorption of the HIV protease inhibitor indinavir using simulated and human intestinal fluids in the in situ intestinal perfusion technique in mice. Although the solubility of indinavir was 6-fold higher in fed state human intestinal fluids (FeHIF) as compared to fasted state HIF (FaHIF), the intestinal permeation of indinavir was 22-fold lower in FeHIF as compared to FaHIF. Dialysis experiments showed that only a small fraction of indinavir is accessible for absorption in FeHIF due to micellar entrapment, possibly explaining its low intestinal permeation. The presence of ritonavir, a known P-gp inhibitor, increased the intestinal permeation of indinavir by 2-fold in FaHIF, while there was no increase when using FeHIF. These data confirm that drug-food interactions form a complex interplay between solubility and permeability effects. The use of HIF in in situ intestinal perfusions holds great promise for biorelevant absorption evaluation as it allows to directly explore this complex solubility/permeability interplay on drug absorption.

  6. The unique paradigm of spirochete motility and chemotaxis

    PubMed Central

    Charon, Nyles W.; Cockburn, Andrew; Li, Chunhao; Liu, Jun; Miller, Kelly A.; Miller, Michael R.; Motaleb, Md.; Wolgemuth, Charles W.

    2013-01-01

    Spirochete motility is enigmatic: It differs from the motility of most other bacteria in that the entire bacterium is involved in translocation in the absence of external appendages. Using the Lyme disease spirochete Borrelia burgdorferi (Bb) as a model system, we explore the current research on spirochete motility and chemotaxis. Bb has periplasmic flagella (PFs) subterminally attached to each end of the protoplasmic cell cylinder, and surrounding the cell is an outer membrane. These internal helically shaped PFs allow the spirochete to swim by generating backward-moving waves by rotation. Exciting advances using cryoelectron microscopy tomography are presented with respect to in situ analysis of cell, PF, and motor structure. In addition, advances in the dynamics of motility, chemotaxis, gene regulation, and the role of motility and chemotaxis in the life cycle of Bb are summarized. The results indicate that the motility paradigms of flagellated bacteria do not apply to these unique bacteria. PMID:22994496

  7. The unique paradigm of spirochete motility and chemotaxis.

    PubMed

    Charon, Nyles W; Cockburn, Andrew; Li, Chunhao; Liu, Jun; Miller, Kelly A; Miller, Michael R; Motaleb, Md A; Wolgemuth, Charles W

    2012-01-01

    Spirochete motility is enigmatic: It differs from the motility of most other bacteria in that the entire bacterium is involved in translocation in the absence of external appendages. Using the Lyme disease spirochete Borrelia burgdorferi (Bb) as a model system, we explore the current research on spirochete motility and chemotaxis. Bb has periplasmic flagella (PFs) subterminally attached to each end of the protoplasmic cell cylinder, and surrounding the cell is an outer membrane. These internal helix-shaped PFs allow the spirochete to swim by generating backward-moving waves by rotation. Exciting advances using cryoelectron tomography are presented with respect to in situ analysis of cell, PF, and motor structure. In addition, advances in the dynamics of motility, chemotaxis, gene regulation, and the role of motility and chemotaxis in the life cycle of Bb are summarized. The results indicate that the motility paradigms of flagellated bacteria do not apply to these unique bacteria.

  8. Dynamic Clustering in Suspension of Motile Bacteria

    NASA Astrophysics Data System (ADS)

    Zhang, Hepeng; Chen, Xiao; Yang, Xiang; Yang, Mingcheng

    2015-03-01

    Bacteria suspension exhibits a wide range of collective phenomena arising from interactions between individual cells. Here we investigate dynamic clusters of motile bacteria near an air-liquid interface. Cell in a cluster orient its flagella perpendicular to the interface and generate attractive radial fluid flow that leads to cluster formation. Rotating cell also creates tangential forces on neighbors that sets clusters into counter-clockwise rotation. We construct a numerical model of self-propelled particles that interact via pair-wise forces extracted from hydrodynamic calculations; such a model reproduces many properties of observed cluster dynamics.

  9. Bisphenol A reduces fertilizing ability and motility by compromising mitochondrial function of sperm.

    PubMed

    Singh, Ram P; Shafeeque, Chathathayil M; Sharma, Sanjeev K; Pandey, Nitin K; Singh, Renu; Mohan, Jag; Kolluri, Gautham; Saxena, Meeta; Sharma, Bhaskar; Sastry, Kochiganti V H; Kataria, Jag M; Azeez, Parappurath A

    2015-07-01

    Bisphenol A (BPA) acts as an endocrine disruptor, affects animal reproductive success in vivo and affects sperm functions in vitro at environmentally relevant concentrations, leading to reduction in sperm motility and fertilizing ability in fish. The effect of in vitro BPA on avian sperm functions has not been explored. The present study examined the effect of environmentally relevant concentrations of BPA (0 mM, 0.18 mM, 0.37 mM, and 0.74 mM) on sperm functions in chicken in vitro. Sperm were exposed to concentrations of BPA for 30 min and analyzed for motility, fertilizing ability, live sperm percentage, and mitochondrial membrane potential (Δψm). Results showed that BPA at a concentration of 0.74 mM significantly decreased motility, fertilizing ability, live sperm count percentage, and sperm Δψm. Sperm motility was positively correlated with fertility (r = 0.73, p ≤ 0.01), live sperm percentage (r = 0.64, p ≤ 0.01), and high Δψm (r = 0.44, p ≤ 0.01). A dose-dependent and time-dependent effect of BPA was observed on sperm motility at all BPA concentrations. However, sperm's fertilizing ability was unaffected in low BPA concentration (0.18 mM and 0.37 mM). A significantly higher percentage of moribund sperm was observed at 0.37 mM and 0.74 mM BPA compared with at 0.18 mM BPA, in the negative control, and in the vehicle control. The present study confirms that environmentally relevant concentrations of BPA are capable of compromising sperm functions, leading to reduction in fertilizing ability of chicken sperm.

  10. Gut microbiota-produced succinate promotes C. difficile infection after antibiotic treatment or motility disturbance.

    PubMed

    Ferreyra, Jessica A; Wu, Katherine J; Hryckowian, Andrew J; Bouley, Donna M; Weimer, Bart C; Sonnenburg, Justin L

    2014-12-10

    Clostridium difficile is a leading cause of antibiotic-associated diarrhea. The mechanisms underlying C. difficile expansion after microbiota disturbance are just emerging. We assessed the gene expression profile of C. difficile within the intestine of gnotobiotic mice to identify genes regulated in response to either dietary or microbiota compositional changes. In the presence of the gut symbiont Bacteroides thetaiotaomicron, C. difficile induces a pathway that metabolizes the microbiota fermentation end-product succinate to butyrate. The low concentration of succinate present in the microbiota of conventional mice is transiently elevated upon antibiotic treatment or chemically induced intestinal motility disturbance, and C. difficile exploits this succinate spike to expand in the perturbed intestine. A C. difficile mutant compromised in succinate utilization is at a competitive disadvantage during these perturbations. Understanding the metabolic mechanisms involved in microbiota-C. difficile interactions may help to identify approaches for the treatment and prevention of C. difficile-associated diseases.

  11. Flagellar motility confers epiphytic fitness advantages upon Pseudomonas syringae

    SciTech Connect

    Haefele, D.M.; Lindow, S.E.

    1987-10-01

    The role of flagellar motility in determining the epiphytic fitness of an ice-nucleation-active strain of Pseudomonas syringae was examined. The loss of flagellar motility reduced the epiphytic fitness of a normally motile P. syringae strain as measured by its growth, survival, and competitive ability on bean leaf surfaces. Equal population sizes of motile parental or nonmotile mutant P. syringae strains were maintained on bean plants for at least 5 days following the inoculation of fully expanded primary leaves. However, when bean seedlings were inoculated before the primary leaves had expanded and bacterial populations on these leaves were quantified at full expansion, the population size of the nonmotile derivative strain reached only 0.9% that of either the motile parental or revertant strain. When fully expanded bean primary leaves were coinoculated with equal numbers of motile and nonmotile cells, the population size of a nonmotile derivative strain was one-third of that of the motile parental or revertant strain after 8 days. Motile and nonmotile cells were exposed in vitro and on plants to UV radiation and desiccating conditions. The motile and nonmotile strains exhibited equal resistance to both stresses in vitro. However, the population size of a nonmotile strain on leaves was less than 20% that of a motile revertant strain when sampled immediately after UV irradiation. Epiphytic populations of both motile and nonmotile P. syringae declined under desiccating conditions on plants, and after 8 days, the population size of a nonmotile strain was less than one-third that of the motile parental or revertant strain.

  12. The effect of vaginal lubricants on sperm motility in vitro.

    PubMed

    Goldenberg, R L; White, R

    1975-09-01

    Apart from the documentation of the spermicidal effects of KY Jelly and Surgilube, little information about the effect of vaginal lubricants on sperm motility has been available. Fifteen substances utilizable as vaginal lubricants were therefore tested for their effect on sperm motility in vitro. Petroleum jelly and glycerin had minimal detrimental effects on motility and apparently are the lubricants of choice when an infertility problem exists.

  13. Flagellar Motility Confers Epiphytic Fitness Advantages upon Pseudomonas syringae

    PubMed Central

    Haefele, Douglas M.; Lindow, Steven E.

    1987-01-01

    The role of flagellar motility in determining the epiphytic fitness of an ice-nucleation-active strain of Pseudomonas syringae was examined. The loss of flagellar motility reduced the epiphytic fitness of a normally motile P. syringae strain as measured by its growth, survival, and competitive ability on bean leaf surfaces. Equal population sizes of motile parental or nonmotile mutant P. syringae strains were maintained on bean plants for at least 5 days following the inoculation of fully expanded primary leaves. However, when bean seedlings were inoculated before the primary leaves had expanded and bacterial populations on these leaves were quantified at full expansion, the population size of the nonmotile derivative strain reached only 0.9% that of either the motile parental or revertant strain. When fully expanded bean primary leaves were coinoculated with equal numbers of motile and nonmotile cells, the population size of a nonmotile derivative strain was one-third of that of the motile parental or revertant strain after 8 days. Motile and nonmotile cells were exposed in vitro and on plants to UV radiation and desiccating conditions. The motile and nonmotile strains exhibited equal resistance to both stresses in vitro. However, the population size of a nonmotile strain on leaves was less than 20% that of a motile revertant strain when sampled immediately after UV irradiation. Epiphytic populations of both motile and nonmotile P. syringae declined under desiccating conditions on plants, and after 8 days, the population size of a nonmotile strain was less than one-third that of the motile parental or revertant strain. PMID:16347469

  14. Intestinal lymphangiectasia in children

    PubMed Central

    Isa, Hasan M.; Al-Arayedh, Ghadeer G.; Mohamed, Afaf M.

    2016-01-01

    Intestinal lymphangiectasia (IL) is a rare disease characterized by dilatation of intestinal lymphatics. It can be classified as primary or secondary according to the underlying etiology. The clinical presentations of IL are pitting edema, chylous ascites, pleural effusion, acute appendicitis, diarrhea, lymphocytopenia, malabsorption, and intestinal obstruction. The diagnosis is made by intestinal endoscopy and biopsies. Dietary modification is the mainstay in the management of IL with a variable response. Here we report 2 patients with IL in Bahrain who showed positive response to dietary modification. PMID:26837404

  15. Intestinal transplantation: a review.

    PubMed

    Desai, Chirag Sureshchandra; Khan, Khalid Mahmood; Girlanda, Raffaele; Fishbein, Thomas M

    2012-09-01

    Parenteral nutrition is a life-saving therapy for patients with intestinal failure. Intestinal transplantation is now recognized as a treatment for patients who develop complications of parenteral nutrition and in whom attempts at intestinal rehabilitation have failed. Patients with parenteral nutrition related liver disease will require a liver graft typically part of a multivisceral transplant. Isolated intestinal transplants are more commonly performed in adults while multivisceral transplants are most commonly performed in infants. Isolated intestinal transplants have the best short-term outcome, with over 80 % survival at 1 year. Patients requiring multivisceral transplants have a high rate of attrition with a 1 year survival less than 70 %. Prognostic factors for a poor outcome include patient hospitalization at the time of transplant and donor age greater than 40 years while systemic sepsis and acute rejection are the major determinant of early postoperative outcome. For patients surviving the first year the outcome of transplantation of the liver in addition to intestine affords some survival advantage though long-term outcome does not yet match other abdominal organs. Outcomes for intestinal retransplantation are poor as a result of immunology and patient debility. Overall intestinal transplantation continues to develop and is a clear indication with cost and quality of life advantages in patients with intestinal failure that do not remain stable on parenteral nutrition.

  16. Microtubule-dependent motility and orientation of the cortical endoplasmic reticulum in elongating characean internodal cells.

    PubMed

    Foissner, Ilse; Menzel, Diedrik; Wasteneys, Geoffrey O

    2009-03-01

    Motility of the endoplasmic reticulum (ER) is predominantly microtubule- dependent in animal cells but thought to be entirely actomyosin-dependent in plant cells. Using live cell imaging and transmission electron microscopy to examine ER motility and structural organization in giant internodal cells of characean algae, we discovered that at the onset of cell elongation, the cortical ER situated near the plasma membrane formed a tight meshwork of predominantly transverse ER tubules that frequently coaligned with microtubules. Microtubule depolymerization increased mesh size and decreased the dynamics of the cortical ER. In contrast, perturbing the cortical actin array with cytochalasins did not affect the transverse orientation but decreased mesh size and increased ER dynamics. Our data suggest that myosin-dependent ER motility is confined to the ER strands in the streaming endoplasm, while the more sedate cortical ER uses microtubule-based mechanisms for organization and motility during early stages of cell elongation. We show further that the ER has an inherent, NEM-sensitive dynamics which can be altered via interaction with the cytoskeleton and that tubule formation and fusion events are cytoskeleton-independent.

  17. Impact of dissolved organic matter on bacterial tactic motility, attachment, and transport.

    PubMed

    Jimenez-Sanchez, Celia; Wick, Lukas Y; Cantos, Manuel; Ortega-Calvo, José-Julio

    2015-04-01

    Bacterial dispersal is a key driver of the ecology of microbial contaminant degradation in soils. This work investigated the role of dissolved organic matter (DOM) in the motility, attachment, and transport of the soil bacterium Pseudomonas putida G7 in saturated porous media. The study is based on the hypothesis that DOM quality is critical to triggering tactic motility and, consequently, affects bacterial transport and dispersal. Sunflower root exudates, humic acids (HA), and the synthetic oleophilic fertilizer S-200 were used as representatives of fresh, weathered, and artificially processed DOM with high nitrogen and phosphorus contents, respectively. We studied DOM levels of 16-130 mg L(-1), which are representative of DOM concentrations typically found in agricultural soil pore water. In contrast to its responses to HA and S-200, strain G7 exhibited a tactic behavior toward root exudates, as quantified by chemotaxis assays and single-cell motility observations. All DOM types promoted bacterial transport through sand at high concentrations (∼ 130 mg L(-1)). At low DOM concentrations (∼ 16 mg L(-1)), the enhancement occurred only in the presence of sunflower root exudates, and this enhancement did not occur with G7 bacteria devoid of flagella. Our results suggest that tactic DOM effectors strongly influence bacterial transport and the interception probability of motile bacteria by collector surfaces. PMID:25734420

  18. Laryngeal motility alteration: A missing link between sleep apnea and vagus nerve stimulation for epilepsy.

    PubMed

    Zambrelli, Elena; Saibene, Alberto M; Furia, Francesca; Chiesa, Valentina; Vignoli, Aglaia; Pipolo, Carlotta; Felisati, Giovanni; Canevini, Maria Paola

    2016-01-01

    This study aimed to evaluate the prevalence and the relationship of sleep breathing disorders (SBDs) and laryngeal motility alterations in patients with drug-resistant epilepsy after vagus nerve stimulator (VNS) implantation. Twenty-three consecutive patients with medically refractory epilepsy underwent out-of-center sleep testing before and after VNS implantation. Eighteen eligible subjects underwent endoscopic laryngeal examination post-VNS implantation. Statistical analysis was carried out to assess an association between laryngeal motility alterations and the onset/worsening of SBDs. After VNS implantation, 11 patients showed a new-onset mild/moderate SBD. Half of the patients already affected by obstructive sleep apnea (OSA) showed worsening of SBD. All of the patients with a new-onset OSA had a laryngeal pattern with left vocal cord adduction (LVCA) during VNS stimulation. The association between VNS-induced LVCA and SBD was statistically significant. This study suggests an association between VNS and SBD, hinting to a pivotal role of laryngeal motility alterations. The relationship between SBD and VNS-induced LVCA supports the need to routinely investigate sleep respiratory and laryngeal motility patterns before and after VNS implantation.

  19. Chemokinetic motility responses of the cyanobacterium oscillatoria terebriformis

    NASA Technical Reports Server (NTRS)

    Richardson, Laurie L.; Castenholz, Richard W.

    1989-01-01

    Oscillatoria terebriformis, a gliding, filamentous, thermophilic cyanobacterium, exhibited an inhibition of gliding motility upon exposure to fructose. The observed response was transient, and the duration of nonmotility was directly proportional to the concentration of fructose. Upon resumption of motility, the rate of motility was also inversely proportional to the concentration of fructose. Sulfide caused a similar response. The effect of sulfide was specific and not due to either anoxia or negative redox potential. Exposure to glucose, acetate, lactate, or mat interstitial water did not elicit any motility response.

  20. Motility Evaluation in the Patient with Inflammatory Bowel Disease.

    PubMed

    Abdalla, Sherine M; Kalra, Gorav; Moshiree, Baha

    2016-10-01

    Patients with inflammatory bowel disease (IBD) suffer frequently from functional bowel diseases (FBD) and motility disorders. Management of FBD and motility disorders in IBD combined with continued treatment of a patient's IBD symptoms will likely lead to better clinical outcomes and improve the patient's quality of life. The goals of this review were to summarize the most recent literature on motility disturbances in patients with IBD and to give a brief overview of the ranges of motility disturbances, from reflux disease to anorectal disorders, and discuss their diagnosis and specific management. PMID:27633599

  1. Motility Evaluation in the Patient with Inflammatory Bowel Disease.

    PubMed

    Abdalla, Sherine M; Kalra, Gorav; Moshiree, Baha

    2016-10-01

    Patients with inflammatory bowel disease (IBD) suffer frequently from functional bowel diseases (FBD) and motility disorders. Management of FBD and motility disorders in IBD combined with continued treatment of a patient's IBD symptoms will likely lead to better clinical outcomes and improve the patient's quality of life. The goals of this review were to summarize the most recent literature on motility disturbances in patients with IBD and to give a brief overview of the ranges of motility disturbances, from reflux disease to anorectal disorders, and discuss their diagnosis and specific management.

  2. Intestinal Autophagy Improves Healthspan and Longevity in C. elegans during Dietary Restriction

    PubMed Central

    Gelino, Sara; Chang, Jessica T.; Kumsta, Caroline; She, Xingyu; Davis, Andrew; Nguyen, Christian; Panowski, Siler; Hansen, Malene

    2016-01-01

    Dietary restriction (DR) is a dietary regimen that extends lifespan in many organisms. One mechanism contributing to the conserved effect of DR on longevity is the cellular recycling process autophagy, which is induced in response to nutrient scarcity and increases sequestration of cytosolic material into double-membrane autophagosomes for degradation in the lysosome. Although autophagy plays a direct role in DR-mediated lifespan extension in the nematode Caenorhabditis elegans, the contribution of autophagy in individual tissues remains unclear. In this study, we show a critical role for autophagy in the intestine, a major metabolic tissue, to ensure lifespan extension of dietary-restricted eat-2 mutants. The intestine of eat-2 mutants has an enlarged lysosomal compartment and flux assays indicate increased turnover of autophagosomes, consistent with an induction of autophagy in this tissue. This increase in intestinal autophagy may underlie the improved intestinal integrity we observe in eat-2 mutants, since whole-body and intestinal-specific inhibition of autophagy in eat-2 mutants greatly impairs the intestinal barrier function. Interestingly, intestinal-specific inhibition of autophagy in eat-2 mutants leads to a decrease in motility with age, alluding to a potential cell non-autonomous role for autophagy in the intestine. Collectively, these results highlight important functions for autophagy in the intestine of dietary-restricted C. elegans. PMID:27414651

  3. Intensification of ciliary motility by extracellular ATP.

    PubMed

    Ovadyahu, D; Eshel, D; Priel, Z

    1988-01-01

    Ciliary metachronism and motility were examined optically in tissue cultures from frog palate epithelium as a function of extracellular ATP concentration in the range of 10(-7)-10(-3) M. The main findings were: a) upon addition of ATP the metachronal wavelength increased by a factor of up to 2. b) the velocity of the metachronal wave increased by a factor of up to 5. c) the frequency of ciliary beating increased by a factor of up to 2-3, the increase being temperature insensitive in the range of 15 degrees C-25 degrees C. d) the area under the 1-second FFT spectrum decreased by a factor of up to 2.5. e) the energy of the metachronal wave is increased by a factor of up to 9.5. f) all the spectrum parameters are subject to influence by ATP, as also by ADP and AMP. However, there are pronounced differences in the various responses to them. Based on these findings, physical aspects of the rate increase of particle transport caused by addition of extracellular ATP are explained. A plausible overall chemical mechanism causing pronounced changes in ciliary motility is discussed.

  4. Bacterial Motility Reveals Unknown Molecular Organization.

    PubMed

    Duchesne, Ismaël; Rainville, Simon; Galstian, Tigran

    2015-11-17

    The water solubility of lyotropic liquid crystals (LCs) makes them very attractive to study the behavior of biological microorganisms in an environment where local symmetry is broken (as often encountered in nature). Several recent studies have shown a dramatic change in the behavior of flagellated bacteria when swimming in solutions of the lyotropic LC disodium cromoglycate (DSCG). In this study, the movements of Escherichia coli bacteria in DSCG-water solutions of different concentrations are observed to improve our understanding of this phenomenon. In addition, the viscosity of DSCG aqueous solutions is measured as a function of concentration at room temperature. We also experimentally identify a previously undescribed isotropic pretransition zone where bacteria start sticking to each other and to surfaces. Simple estimations show that the unbalanced osmotic pressure induced depletion force might be responsible for this sticking phenomenon. An estimate of the bacteria propulsive force and the DSCG aggregates length (versus concentration) are calculated from the measured viscosity of the medium. All these quantities are found to undergo a strong increase in the pretransition zone, starting at a threshold concentration of 6±1 wt % DSCG that is well below the known isotropic-LC transition (∼10 wt %). This study also shines light on the motility of flagellated bacteria in realistic environments, and it opens new avenues for interesting applications such as the use of motile microorganisms to probe the physical properties of their host or smart bandages that could guide bacteria out of wounds.

  5. Rumen motility during induced hyper- and hypocalcaemia.

    PubMed

    Jørgensen, R J; Nyengaard, N R; Hara, S; Enemark, J M; Andersen, P H

    1998-01-01

    Rumen motility was recorded on an experimental cow by means of telemetric signal transfer from strain gauge force transducers fixed surgically on the peritoneal surface of the rumen wall in the left flank. The normocalcaemic cow was given a standard milk fever treatment with calcium borogluconate (400 ml with 14 mg Ca/ml) intravenously. Transient clinical signs were: decreased rumination, muscle ticks, salivation and a heart rate reduction of 20%. Rectal temperature remained unaltered. Frequency of rumen contractions was reduced up to 40% whereas amplitude of contractions did not deviate from baseline values. Hypocalcaemia was induced in a second experiment by iv infusion of Na2EDTA. At 0.60 mmol/l ionized blood calcium periods of no motility were recorded whereas inactivity of rumen activity was persistent at 0.55 mmol/l ionized blood calcium. The cow went down at 0.45-0.48 mmol/l ionized blood calcium at which point the heart rate was increased by 40%. The high sensitivity of the method employed allowed the conclusion that already at a concentration of ionized blood calcium at 1.0 mmol/l both frequency and amplitude of rumen contractions decreased rapidly although eating behaviour and rumination appeared unaffected during the short term observation periods. Implications of this finding towards health and production in transition cows are discussed.

  6. Intracellular Microrheology of Motile Amoeba proteus

    NASA Astrophysics Data System (ADS)

    Rogers, S.; Waigh, T.; Lu, J.

    2008-04-01

    The motility of motile Amoeba proteus was examined using the technique of passive particle tracking microrheology, with the aid of newly-developed particle tracking software, a fast digital camera and an optical microscope. We tracked large numbers of endogeneous particles in the amoebae, which displayed subdiffusive motion at short time scales, corresponding to thermal motion in a viscoelastic medium, and superdiffusive motion at long time scales due to the convection of the cytoplasm. Subdiffusive motion was characterised by a rheological scaling exponent of 3/4 in the cortex, indicative of the semiflexible dynamics of the actin fibres. We observed shear-thinning in the flowing endoplasm, where exponents increased with increasing flow rate; i.e. the endoplasm became more fluid-like. The rheology of the cortex is found to be isotropic, reflecting an isotropic actin gel. A clear difference was seen between cortical and endoplasmic layers in terms of both viscoelasticity and flow velocity, where the profile of the latter is close to a Poiseuille flow for a Newtonian fluid.

  7. Single molecule analysis of cytoplasmic dynein motility

    NASA Astrophysics Data System (ADS)

    Yildiz, Ahmet

    2014-03-01

    Cytoplasmic dynein is a homodimeric AAA + motor that transports a multitude of cargos towards the microtubule (MT) minus end. The mechanism of dynein motility remains unclear, due to its large size (2.6 MDa) and the complexity of its structure. By tracking the stepping motion of both heads at nanometer resolution, we observed that dynein heads move independently along the MT, in contrast to hand over hand movement of kinesins and myosin. Stepping behavior of the heads varies as a function of interhead separation and establishing the basis of high variability in dynein step size. By engineering the mechanical and catalytic properties of the dynein motor domain, we show that a rigid linkage between monomers and dimerization between N-terminal tail domains are not essential for processive movement. Instead, dynein processivity minimally requires the linker domain of one active monomer to be attached to an inert MT tether retaining only the MT-binding domain. The release of a dynein monomer from the MT can be mediated either by nucleotide binding or external load. Nucleotide dependent release is inhibited by the tension on the linker domain at high interhead separations. Tension dependent release is highly asymmetric, with faster release towards the minus-end. Reversing the asymmetry of the MT binding interface results in plus end directed motility, even though the force was generated by the dynein motor activity. On the basis of these measurements, we propose a model that describes the basis of dynein processivity, directionality and force generation.

  8. Mechanics and polarity in cell motility

    NASA Astrophysics Data System (ADS)

    Ambrosi, D.; Zanzottera, A.

    2016-09-01

    The motility of a fish keratocyte on a flat substrate exhibits two distinct regimes: the non-migrating and the migrating one. In both configurations the shape is fixed in time and, when the cell is moving, the velocity is constant in magnitude and direction. Transition from a stable configuration to the other one can be produced by a mechanical or chemotactic perturbation. In order to point out the mechanical nature of such a bistable behaviour, we focus on the actin dynamics inside the cell using a minimal mathematical model. While the protein diffusion, recruitment and segregation govern the polarization process, we show that the free actin mass balance, driven by diffusion, and the polymerized actin retrograde flow, regulated by the active stress, are sufficient ingredients to account for the motile bistability. The length and velocity of the cell are predicted on the basis of the parameters of the substrate and of the cell itself. The key physical ingredient of the theory is the exchange among actin phases at the edges of the cell, that plays a central role both in kinematics and in dynamics.

  9. Epilepsy-induced motility of differentiated neurons.

    PubMed

    Chai, Xuejun; Münzner, Gert; Zhao, Shanting; Tinnes, Stefanie; Kowalski, Janina; Häussler, Ute; Young, Christina; Haas, Carola A; Frotscher, Michael

    2014-08-01

    Neuronal ectopia, such as granule cell dispersion (GCD) in temporal lobe epilepsy (TLE), has been assumed to result from a migration defect during development. Indeed, recent studies reported that aberrant migration of neonatal-generated dentate granule cells (GCs) increased the risk to develop epilepsy later in life. On the contrary, in the present study, we show that fully differentiated GCs become motile following the induction of epileptiform activity, resulting in GCD. Hippocampal slice cultures from transgenic mice expressing green fluorescent protein in differentiated, but not in newly generated GCs, were incubated with the glutamate receptor agonist kainate (KA), which induced GC burst activity and GCD. Using real-time microscopy, we observed that KA-exposed, differentiated GCs translocated their cell bodies and changed their dendritic organization. As found in human TLE, KA application was associated with decreased expression of the extracellular matrix protein Reelin, particularly in hilar interneurons. Together these findings suggest that KA-induced motility of differentiated GCs contributes to the development of GCD and establish slice cultures as a model to study neuronal changes induced by epileptiform activity.

  10. [Intestinal transplant in patients with parenteral nutrition at home].

    PubMed

    de Cos, A I; Gómez Candela, C; Vázquez, C; López Santamaría, M; Vicente, E

    2003-01-01

    Failure of the intestine, whether due to functional or anatomical reasons, constrains Parenteral Nutrition Therapy in children or adults who, as a result of intestinal resections, alterations in motility, diseases of the microvilli or other reasons, present insufficient intestine to cover their needs in terms of nutrients and fluids. Nonetheless, the maintenance of support with parenteral nutrition at home in subjects with irreversible intestinal failure is not without life-threatening complications: liver disease, recurrent sepsis and loss of central routes recommend the assessment of the indication of intestinal transplant in this group of patients. The incidence of morbidity and mortality after intestinal transplant is greater than in other transplants (kidney, liver), but the long-term survival is around 50-60%. In Spain, 7 transplants (6 children and 1 adult) have been performed so far: 3 of intestine alone, 3 of liver plus intestine and 1 mutivisceral transplant. In 4 cases, the indication for transplant was due to terminal liver disease, with the remainder being due to the loss of venous access, intractable diarrhoea and intra-abdominal desmoid tumour, respectively. Except for one girl who presented severe rejection of the graft, the rest achieved digestive autonomy. One boy has presented lymphocyte neoplasia (PTLD) after 2 years and another died after the transplant as a result of a routine liver biopsy (with functioning grafts). Of the 38 patients assessed for transplant, 18 were considered as candidates and of these, three youthful candidates for hepato-intestinal transplant (with short intestine syndrome) have died while on the waiting list and a fourth in the operating theatre prior to an attempted multivisceral transplant. Intestinal transplants must not be considered as the last desperate therapeutic option in patients with permanent intestinal failure. The type of graft, clinical expertise and the use of new inducers (Sirulimos) all contribute to the

  11. Effects of trimebutine on cytosolic Ca2+ and force transitions in intestinal smooth muscle.

    PubMed

    Nagasaki, M; Kobayashi, T; Tamaki, H

    1991-04-01

    The effects of trimebutine maleate on cytosolic free Ca2+ and force transitions in the guinea-pig taenia cecum were studied by fura-2 fluorometry and tension recording. The addition of 80 mM K+ induced a transient increase in cytosolic free Ca2+ concentration ([Ca2+]i) and tension, followed by a sustained increase. Trimebutine (10 microM) suppressed both [Ca2+]i elevation and tension development. The tonic responses were more potently inhibited than the phasic responses. Phasic components gradually increased as the added K+ increased (10-40 mM). The relationship between the peak increases in [Ca2+]i and tension was not affected by trimebutine (10 microM). This means that trimebutine does not affect the Ca2+ sensitivity of contractile elements. In a high K+ and Ca(2+)-free medium, carbachol (10 microM) or caffeine (30 mM) caused transient [Ca2+]i elevation and tension development in the smooth muscle. Trimebutine (10 microM) decreased the amplitude of both responses. Trimebutine (10 microM) inhibited the spontaneous fluctuations in [Ca2+]i and motility of taenia cecum in the presence of tetrodotoxin (TTX; 0.3 microM). These results suggest that trimebutine has two types of inhibitory actions on intestinal smooth muscle; one, the inhibition of Ca2+ influx through voltage-dependent calcium channels, and the other, the inhibition of Ca2+ release from intracellular storage sites. PMID:1868878

  12. Live Imaging of Influenza Infection of the Trachea Reveals Dynamic Regulation of CD8+ T Cell Motility by Antigen

    PubMed Central

    Lambert Emo, Kris; Hyun, Young-min; Barilla, Christopher; Gerber, Scott; Fowell, Deborah; Kim, Minsoo

    2016-01-01

    During a primary influenza infection, cytotoxic CD8+ T cells need to infiltrate the infected airways and engage virus-infected epithelial cells. The factors that regulate T cell motility in the infected airway tissue are not well known. To more precisely study T cell infiltration of the airways, we developed an experimental model system using the trachea as a site where live imaging can be performed. CD8+ T cell motility was dynamic with marked changes in motility on different days of the infection. In particular, significant changes in average cell velocity and confinement were evident on days 8–10 during which the T cells abruptly but transiently increase velocity on day 9. Experiments to distinguish whether infection itself or antigen affect motility revealed that it is antigen, not active infection per se that likely affects these changes as blockade of peptide/MHC resulted in increased velocity. These observations demonstrate that influenza tracheitis provides a robust experimental foundation to study molecular regulation of T cell motility during acute virus infection. PMID:27644089

  13. Live Imaging of Influenza Infection of the Trachea Reveals Dynamic Regulation of CD8+ T Cell Motility by Antigen.

    PubMed

    Lambert Emo, Kris; Hyun, Young-Min; Reilly, Emma; Barilla, Christopher; Gerber, Scott; Fowell, Deborah; Kim, Minsoo; Topham, David J

    2016-09-01

    During a primary influenza infection, cytotoxic CD8+ T cells need to infiltrate the infected airways and engage virus-infected epithelial cells. The factors that regulate T cell motility in the infected airway tissue are not well known. To more precisely study T cell infiltration of the airways, we developed an experimental model system using the trachea as a site where live imaging can be performed. CD8+ T cell motility was dynamic with marked changes in motility on different days of the infection. In particular, significant changes in average cell velocity and confinement were evident on days 8-10 during which the T cells abruptly but transiently increase velocity on day 9. Experiments to distinguish whether infection itself or antigen affect motility revealed that it is antigen, not active infection per se that likely affects these changes as blockade of peptide/MHC resulted in increased velocity. These observations demonstrate that influenza tracheitis provides a robust experimental foundation to study molecular regulation of T cell motility during acute virus infection. PMID:27644089

  14. Balancing Thymocyte Adhesion and Motility: A Functional Linkage Between β1 Lntegrins and The Motility Receptor RHAMM

    PubMed Central

    Gares, Sheryl L.

    2000-01-01

    Thymocyte differentiation involves several processes that occur in different anatomic sites within the thymus. Therefore, thymocytes must have the ability to respond to signals received from stromal cells and adopt either adhesive or motile behavior. We will discuss our data indicating human thymocytes use α4β1 integrin, α5β1 integrin and RHAMM to mediate these activities. Immature multinegative (MN; CD3–4–8–19-) thymocytes use α4β1 and α5β1 integrins to mediate weak and strong adhesion. This subset also uses α4β1 integrin to mediate motility. As thymocytes differentiate, they begin to express and use RHAMM to mediate motility in conjunction with α4β1 and α5β1 integrins. Motile thymocytes use β1 integrins to maintain weakly adhesive contacts with substrate to provide traction for locomoting cells, thus weak adhesion is a requirement of motile behavior. Hyaluronan (HA) is also required by thymocytes to mediate motility. HA binding to cell surface RHAMM redistributes intracellular RHAMM to the cell surface where it functions to mediate motility. We propose that the decision to maintain adhesive or motile behavior is based on the balance between low and high avidity binding conformations of β1 integrins on thymocytes and that RHAMM:HA interactions decrease high avidity binding conformations of integrins pushing the balance toward motile behavior. PMID:11097213

  15. Temporal profile of intestinal tissue expression of intestinal fatty acid-binding protein in a rat model of necrotizing enterocolitis

    PubMed Central

    Simões, Ana Leda Bertoncini; Figueira, Rebeca Lopes; Gonçalves, Frances Lilian Lanhellas; Mitidiero, Luís Felipe Tsuyoshi; Silva, Orlando Castro e; Peiró, José Luis; Sbragia, Lourenço

    2016-01-01

    OBJECTIVES: Necrotizing enterocolitis is a severe multifactorial intestinal disorder that primarily affects preterm newborns, causing 20-40% mortality and morbidity. Intestinal fatty acid-binding protein has been reported to be a biomarker for the detection of intestinal injuries. Our aim was to assess intestinal tissue injury and the molecular expression of intestinal fatty acid-binding protein over time in a necrotizing enterocolitis model. METHODS: A total of 144 Newborn rats were divided into two groups: 1) Control, which received breastfeeding (n=72) and 2) Necrotizing Enterocolitis, which received formula feeding and underwent hypoxia and hypothermia (n=72). A total of six time points of ischemia (2 times a day for 3 days; 12 pups for each time point) were examined. Samples were collected for analysis of body weight, morphological and histological characteristics, intestinal weight, intestinal weight/body weight ratio, injury grade, and intestinal fatty acid-binding protein levels. RESULTS: Body and intestinal weights were lower in the Necrotizing Enterocolitis group than in the Control group (p<0.005 and p<0.0005, respectively). The intestinal weight/body weight ratio was higher in the Necrotizing Enterocolitis group than in the Control group (p<0.005) only at the sixth ischemia time point. The Necrotizing Enterocolitis group displayed higher expression of intestinal fatty acid-binding protein (p<0.0005) and showed greater tissue damage than the Control group. CONCLUSION: Intestinal fatty acid-binding protein was an efficient marker of ischemic injury to the intestine and a good correlation was demonstrated between the time of ischemic injury and the grade of intestinal injury. PMID:27464299

  16. Small-bowel dislocation during long-term MRI observation - insights in intestinal physiology.

    PubMed

    Bickelhaupt, Sebastian; Froehlich, Johannes M; Wentz, Klaus-Ulrich; von Weymarn, Constantin; Patak, Michael A

    2015-01-01

    Magnetic resonance imaging (MRI) of the abdomen is a widely established imaging modality in the diagnostic workup of patients suffering from abdominal disorders. Small-bowel motility analyses using MRI have recently been introduced to provide functional information about the intestine not provided by morphological analyses. This is of clinical importance as motility disorders correlate with inflammation. Yet motility analyses mainly rely on a series of acquisitions in coronal orientation. Temporal displacement of small-bowel loops out of the coronal slice could falsify qualitative and quantitative motility analyses. Thus, our study quantified three-dimensional (3D) dislocation of small-bowel loops during abdominal MRI examinations with the patient lying in prone position to investigate its influence on motility analyses. Our study revealed segmental small-bowel displacement during MRI examinations in prone position to predominantly occur in craniocaudal orientation and in a smaller extent in lateral and ventrodorsal orientation. However, the displacement amplitudes are rather small and might not significantly influence small-bowel motility analyses in 2D coronal plane in general. PMID:24418110

  17. Direct Correlation between Motile Behavior and Protein Abundance in Single Cells.

    PubMed

    Dufour, Yann S; Gillet, Sébastien; Frankel, Nicholas W; Weibel, Douglas B; Emonet, Thierry

    2016-09-01

    Understanding how stochastic molecular fluctuations affect cell behavior requires the quantification of both behavior and protein numbers in the same cells. Here, we combine automated microscopy with in situ hydrogel polymerization to measure single-cell protein expression after tracking swimming behavior. We characterized the distribution of non-genetic phenotypic diversity in Escherichia coli motility, which affects single-cell exploration. By expressing fluorescently tagged chemotaxis proteins (CheR and CheB) at different levels, we quantitatively mapped motile phenotype (tumble bias) to protein numbers using thousands of single-cell measurements. Our results disagreed with established models until we incorporated the role of CheB in receptor deamidation and the slow fluctuations in receptor methylation. Beyond refining models, our central finding is that changes in numbers of CheR and CheB affect the population mean tumble bias and its variance independently. Therefore, it is possible to adjust the degree of phenotypic diversity of a population by adjusting the global level of expression of CheR and CheB while keeping their ratio constant, which, as shown in previous studies, confers functional robustness to the system. Since genetic control of protein expression is heritable, our results suggest that non-genetic diversity in motile behavior is selectable, supporting earlier hypotheses that such diversity confers a selective advantage. PMID:27599206

  18. Direct Correlation between Motile Behavior and Protein Abundance in Single Cells

    PubMed Central

    Gillet, Sébastien; Frankel, Nicholas W.; Weibel, Douglas B.

    2016-01-01

    Understanding how stochastic molecular fluctuations affect cell behavior requires the quantification of both behavior and protein numbers in the same cells. Here, we combine automated microscopy with in situ hydrogel polymerization to measure single-cell protein expression after tracking swimming behavior. We characterized the distribution of non-genetic phenotypic diversity in Escherichia coli motility, which affects single-cell exploration. By expressing fluorescently tagged chemotaxis proteins (CheR and CheB) at different levels, we quantitatively mapped motile phenotype (tumble bias) to protein numbers using thousands of single-cell measurements. Our results disagreed with established models until we incorporated the role of CheB in receptor deamidation and the slow fluctuations in receptor methylation. Beyond refining models, our central finding is that changes in numbers of CheR and CheB affect the population mean tumble bias and its variance independently. Therefore, it is possible to adjust the degree of phenotypic diversity of a population by adjusting the global level of expression of CheR and CheB while keeping their ratio constant, which, as shown in previous studies, confers functional robustness to the system. Since genetic control of protein expression is heritable, our results suggest that non-genetic diversity in motile behavior is selectable, supporting earlier hypotheses that such diversity confers a selective advantage. PMID:27599206

  19. Vasoactive Intestinal Polypeptide Promotes Intestinal Barrier Homeostasis and Protection Against Colitis in Mice

    PubMed Central

    Wu, Xiujuan; Conlin, Victoria S.; Morampudi, Vijay; Ryz, Natasha R.; Nasser, Yasmin; Bhinder, Ganive; Bergstrom, Kirk S.; Yu, Hong B.; Waterhouse, Chris C. M.; Buchan, Allison M. J.; Popescu, Oana E.; Gibson, William T.; Waschek, James A.; Vallance, Bruce A.; Jacobson, Kevan

    2015-01-01

    Inflammatory bowel disease is a chronic gastrointestinal inflammatory disorder associated with changes in neuropeptide expression and function, including vasoactive intestinal peptide (VIP). VIP regulates intestinal vasomotor and secretomotor function and motility; however, VIP’s role in development and maintenance of colonic epithelial barrier homeostasis is unclear. Using VIP deficient (VIPKO) mice, we investigated VIP’s role in epithelial barrier homeostasis, and susceptibility to colitis. Colonic crypt morphology and epithelial barrier homeostasis were assessed in wildtype (WT) and VIPKO mice, at baseline. Colitic responses were evaluated following dinitrobenzene sulfonic acid (DNBS) or dextran-sodium sulfate (DSS) exposure. Mice were also treated with exogenous VIP. At baseline, VIPKO mice exhibited distorted colonic crypts, defects in epithelial cell proliferation and migration, increased apoptosis, and altered permeability. VIPKO mice also displayed reduced goblet cell numbers, and reduced expression of secreted goblet cell factors mucin 2 and trefoil factor 3. These changes were associated with reduced expression of caudal type homeobox 2 (Cdx2), a master regulator of intestinal function and homeostasis. DNBS and DSS-induced colitis were more severe in VIPKO than WT mice. VIP treatment rescued the phenotype, protecting VIPKO mice against DSS colitis, with results comparable to WT mice. In conclusion, VIP plays a crucial role in the development and maintenance of colonic epithelial barrier integrity under physiological conditions and promotes epithelial repair and homeostasis during colitis. PMID:25932952

  20. Insect Stage-Specific Adenylate Cyclases Regulate Social Motility in African Trypanosomes

    PubMed Central

    Lopez, Miguel A.; Saada, Edwin A.

    2014-01-01

    Sophisticated systems for cell-cell communication enable unicellular microbes to act as multicellular entities capable of group-level behaviors that are not evident in individuals. These group behaviors influence microbe physiology, and the underlying signaling pathways are considered potential drug targets in microbial pathogens. Trypanosoma brucei is a protozoan parasite that causes substantial human suffering and economic hardship in some of the most impoverished regions of the world. T. brucei lives on host tissue surfaces during transmission through its tsetse fly vector, and cultivation on surfaces causes the parasites to assemble into multicellular communities in which individual cells coordinate their movements in response to external signals. This behavior is termed “social motility,” based on its similarities with surface-induced social motility in bacteria, and it demonstrates that trypanosomes are capable of group-level behavior. Mechanisms governing T. brucei social motility are unknown. Here we report that a subset of receptor-type adenylate cyclases (ACs) in the trypanosome flagellum regulate social motility. RNA interference-mediated knockdown of adenylate cyclase 6 (AC6), or dual knockdown of AC1 and AC2, causes a hypersocial phenotype but has no discernible effect on individual cells in suspension culture. Mutation of the AC6 catalytic domain phenocopies AC6 knockdown, demonstrating that loss of adenylate cyclase activity is responsible for the phenotype. Notably, knockdown of other ACs did not affect social motility, indicating segregation of AC functions. These studies reveal interesting parallels in systems that control social behavior in trypanosomes and bacteria and provide insight into a feature of parasite biology that may be exploited for novel intervention strategies. PMID:25416239

  1. Insect stage-specific adenylate cyclases regulate social motility in African trypanosomes.

    PubMed

    Lopez, Miguel A; Saada, Edwin A; Hill, Kent L

    2015-01-01

    Sophisticated systems for cell-cell communication enable unicellular microbes to act as multicellular entities capable of group-level behaviors that are not evident in individuals. These group behaviors influence microbe physiology, and the underlying signaling pathways are considered potential drug targets in microbial pathogens. Trypanosoma brucei is a protozoan parasite that causes substantial human suffering and economic hardship in some of the most impoverished regions of the world. T. brucei lives on host tissue surfaces during transmission through its tsetse fly vector, and cultivation on surfaces causes the parasites to assemble into multicellular communities in which individual cells coordinate their movements in response to external signals. This behavior is termed "social motility," based on its similarities with surface-induced social motility in bacteria, and it demonstrates that trypanosomes are capable of group-level behavior. Mechanisms governing T. brucei social motility are unknown. Here we report that a subset of receptor-type adenylate cyclases (ACs) in the trypanosome flagellum regulate social motility. RNA interference-mediated knockdown of adenylate cyclase 6 (AC6), or dual knockdown of AC1 and AC2, causes a hypersocial phenotype but has no discernible effect on individual cells in suspension culture. Mutation of the AC6 catalytic domain phenocopies AC6 knockdown, demonstrating that loss of adenylate cyclase activity is responsible for the phenotype. Notably, knockdown of other ACs did not affect social motility, indicating segregation of AC functions. These studies reveal interesting parallels in systems that control social behavior in trypanosomes and bacteria and provide insight into a feature of parasite biology that may be exploited for novel intervention strategies. PMID:25416239

  2. Electroacupuncture at ST25 inhibits jejunal motility: Role of sympathetic pathways and TRPV1

    PubMed Central

    Yu, Zhi; Zhang, Na; Lu, Chun-Xia; Pang, Ting-Ting; Wang, Kai-Yue; Jiang, Jing-Feng; Zhu, Bing; Xu, Bin

    2016-01-01

    AIM: To investigate whether electroacupuncture (EA) at ST25 affects jejunal motility in vivo and if so, whether a sympathetic pathway is involved. METHODS: Jejunal motility was assessed using a manometric balloon placed in the jejunum approximately about 3-5 cm away from the suspensory ligament of the duodenum in anesthetized animals. The effects of EA at ST25 were measured in male Sprague-Dawley rats, some of which were treated with propranolol or clenbuterol (EA intensities: 1, 3, 5, 7, and 9 mA), and in male transient receptor potential vanilloid-1 (TRPV1) (capsaicin receptor) knockout mice (EA intensities: 1, 2, and 4 mA). RESULTS: Anesthetized rats exhibited three types of fasting jejunal motor patterns (types A, B, and C), and only type C rats responded to EA stimulation. In type C rats, EA at ST25 significantly suppressed the motor activity of the jejunum in an intensity-dependent manner. The inhibitory effect of EA was weakened by propranolol (β adrenoceptor antagonist) and disappeared with clenbuterol (β adrenoceptor agonist) induced inhibition of motility, suggesting that the effect of EA on motility is mediated via a sympathetic pathway. Compared with wild-type mice, EA at ST25 was less effective in TRPV1 knockout mice, suggesting that this multi-modal sensor channel participates in the mechanism. CONCLUSION: EA at ST25 was found to inhibit jejunal motility in an intensity-dependent manner, via a mechanism in which sympathetic nerves and TRPV1 receptors play an important role. PMID:26855542

  3. Motility and Chemotaxis in Agrobacterium tumefaciens Surface Attachment and Biofilm Formation▿ †

    PubMed Central

    Merritt, Peter M.; Danhorn, Thomas; Fuqua, Clay

    2007-01-01

    Bacterial motility mechanisms, including swimming, swarming, and twitching, are known to have important roles in biofilm formation, including colonization and the subsequent expansion into mature structured surface communities. Directed motility requires chemotaxis functions that are conserved among many bacterial species. The biofilm-forming plant pathogen Agrobacterium tumefaciens drives swimming motility by utilizing a small group of flagella localized to a single pole or the subpolar region of the cell. There is no evidence for twitching or swarming motility in A. tumefaciens. Site-specific deletion mutations that resulted in either aflagellate, flagellated but nonmotile, or flagellated but nonchemotactic A. tumefaciens derivatives were examined for biofilm formation under static and flowing conditions. Nonmotile mutants were significantly deficient in biofilm formation under static conditions. Under flowing conditions, however, the aflagellate mutant rapidly formed aberrantly dense, tall biofilms. In contrast, a nonmotile mutant with unpowered flagella was clearly debilitated for biofilm formation relative to the wild type. A nontumbling chemotaxis mutant was only weakly affected with regard to biofilm formation under nonflowing conditions but was notably compromised in flow, generating less adherent biomass than the wild type, with a more dispersed cellular arrangement. Extragenic suppressor mutants of the chemotaxis-impaired, straight-swimming phenotype were readily isolated from motility agar plates. These mutants regained tumbling at a frequency similar to that of the wild type. Despite this phenotype, biofilm formation by the suppressor mutants in static cultures was significantly deficient. Under flowing conditions, a representative suppressor mutant manifested a phenotype similar to yet distinct from that of its nonchemotactic parent. PMID:17766409

  4. Laser radiation and motility patterns of human sperm

    SciTech Connect

    Lenzi, A.; Claroni, F.; Gandini, L.; Lombardo, F.; Barbieri, C.; Lino, A.; Dondero, F. )

    1989-01-01

    Human sperm were exposed in vitro to laser radiation. An increase in progressive sperm motility was associated with a faster rate of sperm ATP consumption. Computer-assisted analysis of sperm motility confirmed the positive effect of laser irradiation on velocity and linearity of sperm.

  5. Determining the Relative Contribution and Hierarchy of hha and qseBC in the Regulation of Flagellar Motility of Escherichia coli O157:H7

    PubMed Central

    Sharma, Vijay K.; Casey, Thomas A.

    2014-01-01

    In recent studies, we demonstrated that a deletion of hha caused increased secretion of locus of enterocyte encoded adherence proteins and reduced motility of enterohemorrhagic Escherichia coli (EHEC) O157:H7. In addition to the importance of hha in positive regulation of motility, a two-component quorum sensing pathway encoded by the qseBC genes has been shown to activate bacterial motility in response to mammalian stress hormones epinephrine and norepinephrine as well as bacterially produced autoinducer-3. In this study, we compared regulatory contribution and hierarchy of hha, a member of the Hha/YmoA family of nucleoid-associated proteins, to that of qseBC in the expression of EHEC O157:H7 motility. Since norepinephrine affects motility of EHEC O157:H7 through a qseBC-encoded two-component quorum sensing signaling, we also determined whether the hha-mediated regulation of motility is affected by norepinephrine and whether this effect is qseBC dependent. We used single (Δhha or ΔqseC) and double (Δhha ΔqseC) deletion mutants to show that hha exerts a greater positive regulatory effect in comparison to qseBC on the expression of motility by EHEC O157:H7. We also show that Hha is hierarchically superior in transcriptional regulation of motility than QseBC because transcription of qseC was significantly reduced in the hha deletion mutant compared to that in the parental and the hha-complemented mutant strains. These results suggest that hha regulates motility of EHEC O157:H7 directly as well as indirectly by controlling the transcription of qseBC. PMID:24465756

  6. Detection and genomic characterization of motility in Lactobacillus curvatus: confirmation of motility in a species outside the Lactobacillus salivarius clade.<