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Sample records for acute mucosal pathogenesis

  1. Acute mucosal pathogenesis of feline immunodeficiency virus is independent of viral dose in vaginally infected cats

    PubMed Central

    2010-01-01

    Background The mucosal pathogenesis of HIV has been shown to be an important feature of infection and disease progression. HIV-1 infection causes depletion of intestinal lamina propria CD4+ T cells (LPL), therefore, intestinal CD4+ T cell preservation may be a useful correlate of protection in evaluating vaccine candidates. Vaccine studies employing the cat/FIV and macaque/SIV models frequently use high doses of parenterally administered challenge virus to ensure high plasma viremia in control animals. However, it is unclear if loss of mucosal T cells would occur regardless of initial viral inoculum dose. The objective of this study was to determine the acute effect of viral dose on mucosal leukocytes and associated innate and adaptive immune responses. Results Cats were vaginally inoculated with a high, middle or low dose of cell-associated and cell-free FIV. PBMC, serum and plasma were assessed every two weeks with tissues assessed eight weeks following infection. We found that irrespective of mucosally administered viral dose, FIV infection was induced in all cats. However, viremia was present in only half of the cats, and viral dose was unrelated to the development of viremia. Importantly, regardless of viral dose, all cats experienced significant losses of intestinal CD4+ LPL and CD8+ intraepithelial lymphocytes (IEL). Innate immune responses by CD56+CD3- NK cells correlated with aviremia and apparent occult infection but did not protect mucosal T cells. CD4+ and CD8+ T cells in viremic cats were more likely to produce cytokines in response to Gag stimulation, whereas aviremic cats T cells tended to produce cytokines in response to Env stimulation. However, while cell-mediated immune responses in aviremic cats may have helped reduce viral replication, they could not be correlated to the levels of viremia. Robust production of anti-FIV antibodies was positively correlated with the magnitude of viremia. Conclusions Our results indicate that mucosal immune

  2. Microbiota and their role in the pathogenesis of oral mucositis.

    PubMed

    Vanhoecke, B; De Ryck, T; Stringer, A; Van de Wiele, T; Keefe, D

    2015-01-01

    Oral mucositis in patients undergoing cancer therapy is a significant problem. Its prevalence ranges between 20 and 100%, depending on treatment type and protocols and patient-based variables. Mucositis is self-limiting when uncomplicated by infection. Unfortunately, the incidence of developing a local or systemic infection during the course of the treatment is very high. At this stage, it is unclear which role oral microbiota play in the onset, duration, and severity of oral mucositis. Nevertheless, there is growing interest in this underexplored topic, and new studies are being undertaken to unravel their impact on the pathogenesis of mucositis. PMID:24456144

  3. Pathogenesis of mucosal biofilm infections: challenges and progress

    PubMed Central

    Dongari-Bagtzoglou, Anna

    2009-01-01

    Living-tissue biofilms remained unrecognized until very recently, mainly as a result of traditional microbial sampling techniques or histologic processing, which disrupt the spatial organization of the tissue microorganisms. Thus, the biofilm nature of certain mucosal infections was frequently unintentionally missed or disregarded. To a large extent, the study of human tissue biofilms is still in its infancy. However, with the advent of newer methodologies, such as fluorescent in situ hybridization and endoscopic confocal laser scanning microscopy, which combine the identification of microbes with in situ, direct visualization of their relationships with each other and with their substratum, mucosal tissue biofilms are becoming easier to study and, thus, their role in human infections is becoming more apparent. This review summarizes the challenges in the study of tissue biofilms, proposes two inflammation-centered – albeit opposite – pathogenetic models of mucosal tissue biofilm infections and suggests directions for future research and novel therapeutic approaches. PMID:18380602

  4. Mucosal transmission and pathogenesis of chronic wasting disease in ferrets.

    PubMed

    Perrott, Matthew R; Sigurdson, Christina J; Mason, Gary L; Hoover, Edward A

    2013-02-01

    Chronic wasting disease (CWD) of cervids is almost certainly transmitted by mucosal contact with the causative prion, whether by direct (animal-to-animal) or indirect (environmental) means. Yet the sites and mechanisms of prion entry remain to be further understood. This study sought to extend this understanding by demonstrating that ferrets exposed to CWD via several mucosal routes developed infection, CWD prion protein (PrP(CWD)) amplification in lymphoid tissues, neural invasion and florid transmissible spongiform encephalopathy lesions resembling those in native cervid hosts. The ferrets developed extensive PrP(CWD) accumulation in the nervous system, retina and olfactory epithelium, with lesser deposition in tongue, muscle, salivary gland and the vomeronasal organ. PrP(CWD) accumulation in mucosal sites, including upper respiratory tract epithelium, olfactory epithelium and intestinal Peyer's patches, make the shedding of prions by infected ferrets plausible. It was also observed that regionally targeted exposure of the nasopharyngeal mucosa resulted in an increased attack rate when compared with oral exposure. The latter finding suggests that nasal exposure enhances permissiveness to CWD infection. The ferret model has further potential for investigation of portals for initiation of CWD infection. PMID:23100363

  5. Oropharyngeal mucositis in cancer therapy. Review of pathogenesis, diagnosis, and management.

    PubMed

    Epstein, Joel B; Schubert, Mark M

    2003-12-01

    Oropharyngeal mucositis is a common and treatment-limiting side effect of cancer therapy. Severe oral mucositis can lead to the need to interrupt or discontinue cancer therapy and thus may have an impact on cure of the primary disease. Mucositis may also increase the risk of local and systemic infection and significantly affects quality of life and cost of care. Current care of patients with mucositis is essentially palliative and includes appropriate oral hygiene, nonirritating diet and oral care products, topical palliative mouth rinses, topical anesthetics, and opioid analgesics. Systemic analgesics are the mainstay of pain management. Topical approaches to pain management are under investigation. The literature supports use of benzydamine for prophylaxis of mucositis caused by conventional fractionationated head and neck radiotherapy, and cryotherapy for short-half-life stomatoxic chemotherapy, such as bolus fluorouracil. Continuing studies are investigating the potential use of biologic response modifiers and growth factors, including topical and systemic delivery of epithelial growth factors and agents. Progress in the prevention and management of mucositis will improve quality of life, reduce cost of care, and facilitate completion of more intensive cancer chemotherapy and radiotherapy protocols. In addition, improved management of mucositis may allow implementation of cancer treatment protocols that are currently excessively mucotoxic but may produce higher cure rates. Continuing research related to the pathogenesis and management of mucositis will undoubtedly lead to the development of potential interventions and improved patient care. PMID:14723014

  6. Effects of Mycotoxins on Mucosal Microbial Infection and Related Pathogenesis

    PubMed Central

    Park, Seong-Hwan; Kim, Dongwook; Kim, Juil; Moon, Yuseok

    2015-01-01

    Mycotoxins are fungal secondary metabolites detected in many agricultural commodities and water-damaged indoor environments. Susceptibility to mucosal infectious diseases is closely associated with immune dysfunction caused by mycotoxin exposure in humans and other animals. Many mycotoxins suppress immune function by decreasing the proliferation of activated lymphocytes, impairing phagocytic function of macrophages, and suppressing cytokine production, but some induce hypersensitive responses in different dose regimes. The present review describes various mycotoxin responses to infectious pathogens that trigger mucosa-associated diseases in the gastrointestinal and respiratory tracts of humans and other animals. In particular, it focuses on the effects of mycotoxin exposure on invasion, pathogen clearance, the production of cytokines and immunoglobulins, and the prognostic implications of interactions between infectious pathogens and mycotoxin exposure. PMID:26529017

  7. [Etiology and pathogenesis of acute respiratory failure].

    PubMed

    Ziliene, Violeta; Kondrotas, Anatolijus Juozas; Kevelaitis, Egidijus

    2004-01-01

    The aim of this study was to determine factors influencing acute respiratory failure and pathogenesis according to literature and clinical findings in critically ill patients. The term "respiratory failure" implies the inability to maintain either the normal delivery of oxygen to tissues and release or the normal removal of carbon dioxide from the tissues. There are many patients suffering from acute respiratory failure caused by nosocomial pneumonia, septic syndrome, aspiration, interstitial or alveolar lung edema, thromboembolism of a. pulmonalis, polytrauma and lung contusion, acute respiratory distress syndrome, long-term mechanical ventilation of the lungs, acute lung injury, status asthmaticus, rather massive transfusions of blood products, and lipid embolism in the intensive care unit. There are actually three processes involved: the transfer of oxygen across the alveolus, the transport to the tissues (by cardiac output), and the removal of carbon dioxide from blood into the alveolus with subsequent exhalation into the environment. Failure of any step in this process can lead to respiratory failure. Long-term hypoxia causes ischemic changes and dysfunction of brain, heart, kidney, lungs and can worsen the course of disease or cause higher mortality. It is important to determine the pathogenetic mechanisms of acute respiratory failure, estimate the main parameters and their interrelations and prescribe proper treatment. PMID:15064552

  8. Treatment and pathogenesis of acute hyperkalemia

    PubMed Central

    Mushiyakh, Yelena; Dangaria, Harsh; Qavi, Shahbaz; Ali, Noorjahan; Pannone, John; Tompkins, David

    2012-01-01

    This article focuses on the pathogenesis, clinical manifestations, and various treatment modalities for acute hyperkalemia and presents a systematic approach to selecting a treatment strategy. Hyperkalemia, a life-threatening condition caused by extracellular potassium shift or decreased renal potassium excretion, usually presents with non-specific symptoms. Early recognition of moderate to severe hyperkalemia is vital in preventing fatal cardiac arrhythmias and muscle paralysis. Management of hyperkalemia includes the elimination of reversible causes (diet, medications), rapidly acting therapies that shift potassium into cells and block the cardiac membrane effects of hyperkalemia, and measures to facilitate removal of potassium from the body (saline diuresis, oral binding resins, and hemodialysis). Hyperkalemia with potassium level more than 6.5 mEq/L or EKG changes is a medical emergency and should be treated accordingly. Treatment should be started with calcium gluconate to stabilize cardiomyocyte membranes, followed by insulin injection, and b-agonists administration. Hemodialysis remains the most reliable method to remove potassium from the body and should be used in cases refractory to medical treatment. Prompt detection and proper treatment are crucial in preventing lethal outcomes. PMID:23882341

  9. Acute appendicitis following endoscopic mucosal resection of cecal adenoma.

    PubMed

    Nemoto, Yukako; Tokuhisa, Junya; Shimada, Nagasato; Gomi, Tatsuya; Maetani, Iruru

    2015-07-21

    Endoscopic mucosal resection (EMR) allows the removal of flat or sessile lesions, laterally spreading tumors, and carcinoma of the colon or the rectum limited to the mucosa or the superficial submucosa. Acute appendicitis is the most common abdominal emergency requiring emergency surgery, and it is also a rare complication of diagnostic colonoscopy and therapeutic endoscopy, including EMR. In the case presented here, a 53-year-old female underwent colonoscopy due to a positive fecal occult blood test and was diagnosed with cecal adenoma. She was referred to our hospital and admitted for treatment. The patient had no other symptoms. EMR was performed, and 7 h after the surgery, the patient experienced right -lower abdominal pain. Laboratory tests performed the following day revealed a WBC count of 16000/mm(3), a neutrophil count of 14144/mm(3), and a C-reactive protein level of 2.20 mg/dL, indicating an inflammatory response. Computed tomography also revealed appendiceal wall thickening and swelling, so acute appendicitis following EMR was diagnosed. Antibiotics were initiated leading to total resolution of the symptoms, and the patient was discharged on the sixth post-operative day. Pathological analysis revealed a high-grade cecal tubular adenoma. Such acute appendicitis following EMR is extremely rare, and EMR of the cecum may be a rare cause of acute appendicitis. PMID:26217100

  10. Acute appendicitis following endoscopic mucosal resection of cecal adenoma

    PubMed Central

    Nemoto, Yukako; Tokuhisa, Junya; Shimada, Nagasato; Gomi, Tatsuya; Maetani, Iruru

    2015-01-01

    Endoscopic mucosal resection (EMR) allows the removal of flat or sessile lesions, laterally spreading tumors, and carcinoma of the colon or the rectum limited to the mucosa or the superficial submucosa. Acute appendicitis is the most common abdominal emergency requiring emergency surgery, and it is also a rare complication of diagnostic colonoscopy and therapeutic endoscopy, including EMR. In the case presented here, a 53-year-old female underwent colonoscopy due to a positive fecal occult blood test and was diagnosed with cecal adenoma. She was referred to our hospital and admitted for treatment. The patient had no other symptoms. EMR was performed, and 7 h after the surgery, the patient experienced right -lower abdominal pain. Laboratory tests performed the following day revealed a WBC count of 16000/mm3, a neutrophil count of 14144/mm3, and a C-reactive protein level of 2.20 mg/dL, indicating an inflammatory response. Computed tomography also revealed appendiceal wall thickening and swelling, so acute appendicitis following EMR was diagnosed. Antibiotics were initiated leading to total resolution of the symptoms, and the patient was discharged on the sixth post-operative day. Pathological analysis revealed a high-grade cecal tubular adenoma. Such acute appendicitis following EMR is extremely rare, and EMR of the cecum may be a rare cause of acute appendicitis. PMID:26217100

  11. Interplay between Helicobacter pylori and immune cells in immune pathogenesis of gastric inflammation and mucosal pathology

    PubMed Central

    Tsai, Hwei-Fang; Hsu, Ping-Ning

    2010-01-01

    Helicobacter pylori infection is associated with an inflammatory response in the gastric mucosa, leading to chronic gastritis, peptic ulcers, gastric carcinoma and gastric mucosa-associated lymphoid tissue (MALT) lymphomas. Recent studies have shown that apoptosis of gastric epithelial cells is increased during H. pylori infection. Apoptosis induced by microbial infections are factors implicated in the pathogenesis of H. pylori infection. The enhanced gastric epithelial cell apoptosis in H. pylori infection has been suggested to play an important role in the pathogenesis of chronic gastritis and gastric pathology. In addition to directly triggering apoptosis, H. pylori induces sensitivity to tumor-necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis in gastric epithelial cells via modulation of TRAIL apoptosis signaling. Moreover, H. pylori infection induces infiltration of T lymphocytes and triggers inflammation to augment apoptosis. In H. pylori infection, there was significantly increased CCR6+CD3+ T-cell infiltration in the gastric mucosa, and the CCR6 ligand, CCL20 chemokine, was selectively expressed in inflamed gastric tissues. These results implicate that the interaction between CCL20 and CCR6 may play a role in recruiting T cells to the sites of inflammation in the gastric mucosa during Helicobacter infection. Through these mechanisms, chemokine-mediated T lymphocyte trafficking into inflamed epithelium is initiated and the mucosal injury in Helicobacter infection is induced. This article will review the recent novel findings on the interactions of H. pylori with diverse host epithelial signaling pathways and events involved in the initiation of gastric pathology, including gastric inflammation, mucosal damage and development of MALT lymphomas. PMID:20190789

  12. Gut barrier structure, mucosal immunity and intestinal microbiota in the pathogenesis and treatment of HIV infection.

    PubMed

    Tincati, Camilla; Douek, Daniel C; Marchetti, Giulia

    2016-01-01

    Over the past 10 years, extensive work has been carried out in the field of microbial translocation in HIV infection, ranging from studies on its clinical significance to investigations on its pathogenic features. In the present work, we review the most recent findings on this phenomenon, focusing on the predictive role of microbial translocation in HIV-related morbidity and mortality, the mechanisms by which it arises and potential therapeutic approaches. From a clinical perspective, current work has shown that markers of microbial translocation may be useful in predicting clinical events in untreated HIV infection, while conflicting data exist on their role in cART-experienced subjects, possibly due to the inclusion of extremely varied patient populations in cohort studies. Results from studies addressing the pathogenesis of microbial translocation have improved our knowledge of the damage of the gastrointestinal epithelial barrier occurring in HIV infection. However, the extent to which mucosal impairment translates directly to increased gastrointestinal permeability remains an open issue. In this respect, novel work has established a role for IL-17 and IL-22-secreting T cell populations in limiting microbial translocation and systemic T-cell activation/inflammation, thus representing a possible target of immune-therapeutic interventions shown to be promising in the animal model. Further, recent reports have not only confirmed the presence of a dysbiotic intestinal community in the course of HIV infection but have also shown that it may be linked to mucosal damage, microbial translocation and peripheral immune activation. Importantly, technical advances have also shed light on the metabolic activity of gut microbes, highlighting the need for novel therapeutic approaches to correct the function, as well as the composition, of the gastrointestinal microbiota. PMID:27073405

  13. Candida albicans VPS4 contributes differentially to epithelial and mucosal pathogenesis

    PubMed Central

    Rane, Hallie S; Hardison, Sarah; Botelho, Claudia; Bernardo, Stella M; Wormley, Floyd; Lee, Samuel A

    2014-01-01

    We have previously demonstrated that the C. albicans pre-vacuolar protein sorting gene VPS4 is required for extracellular secretion of the secreted aspartyl proteases Sap2p and Saps4–6p. Furthermore, the vps4Δ null mutant has been shown to be markedly hypovirulent in a murine tail vein model of disseminated candidiasis. In these experiments, we sought to further define the role of the pre-vacuolar secretion pathway mediated by the pre-vacuolar sorting gene VPS4 in the pathogenesis of epithelial and mucosal infection using a broad range of virulence models. The C. albicans vps4Δ mutant demonstrates reduced tolerance of cell wall stresses compared to its isogenic, complemented control strain. In an in vitro oral epithelial model (OEM) of tissue invasion, the vps4Δ mutant caused reduced tissue damage compared to controls. Further, the vps4Δ mutant was defective in macrophage killing in vitro, and was attenuated in virulence in an in vivo Caenorhabditis elegans model representative of intestinal epithelial infection. In contrast, the vps4Δ mutant caused a similar degree of tissue damage in an in vitro uroepithelial model of Candida infection compared with controls. Furthermore, in an in vivo murine model of vaginal candidiasis there was no reduction in fungal colony burden and no differences in vaginal histopathology compared to wild-type and complemented controls. These results suggest that VPS4 contributes to several key aspects of oral epithelial but not uroepithelial infection, and in contrast to systemic infection, plays no major role in the pathogenesis of Candida vaginitis. By using a wide range of virulence models, we demonstrate that C. albicans VPS4 contributes to virulence according to the specific tissue that is infected. Thus, in order to gain a full understanding of C. albicans virulence in relation to a particular gene or pathway of interest, a selected range of infection models may need to be utilized. PMID:25483774

  14. [Polonium-210 acute and chronic pathomorphology and pathogenesis].

    PubMed

    Kvacheva, Yu E

    2015-01-01

    In the present review, the data on the pathology of acute and chronic polonium injuries available from the an open-access domestic and foreign literature are primarily systemized and analyzed. The historical background of the research is presented in brief. On the basis of clinical and experimental generalizations, the current concept regarding the pathogenesis of polonium intoxication has been developed. PMID:26856053

  15. OCT visualization of acute radiation mucositis: pilot study

    NASA Astrophysics Data System (ADS)

    Gladkova, Natalia; Maslennikova, Anna; Terentieva, Anna; Fomina, Yulia; Khomutinnikova, Nina; Balalaeva, Irina; Vyseltseva, Yulia; Larin, Roman; Kornoukhova, Natalia; Shakhov, Andrey; Shakhova, Natalia; Gelikonov, Grigory; Kamensky, Vladislav; Feldchtein, Felix

    2005-08-01

    We present pilot results in optical coherence tomography (OCT) visualization of normal mucosa radiation damage. 15 patients undergoing radiation treatment of head and neck cancer were enrolled. OCT was used to monitor the mucositis development during and after treatment. OCT can see stages of radiation mucositis development, including hidden ones, before any clinical manifestations.

  16. Oral Administration of Escin Inhibits Acute Inflammation and Reduces Intestinal Mucosal Injury in Animal Models.

    PubMed

    Li, Minmin; Lu, Chengwen; Zhang, Leiming; Zhang, Jianqiao; Du, Yuan; Duan, Sijin; Wang, Tian; Fu, Fenghua

    2015-01-01

    The present study aimed to investigate the effects of oral administration of escin on acute inflammation and intestinal mucosal injury in animal models. The effects of escin on carrageenan-induced paw edema in a rat model of acute inflammation, cecal ligation and puncture (CLP) induced intestinal mucosal injury in a mouse model, were observed. It was shown that oral administration of escin inhibits carrageenan-induced paw edema and decreases the production of prostaglandin E2 (PGE2) and cyclooxygenase- (COX-) 2. In CLP model, low dose of escin ameliorates endotoxin induced liver injury and intestinal mucosal injury and increases the expression of tight junction protein claudin-5 in mice. These findings suggest that escin effectively inhibits acute inflammation and reduces intestinal mucosal injury in animal models. PMID:26199634

  17. Oral Administration of Escin Inhibits Acute Inflammation and Reduces Intestinal Mucosal Injury in Animal Models

    PubMed Central

    Li, Minmin; Lu, Chengwen; Zhang, Leiming; Zhang, Jianqiao; Du, Yuan; Duan, Sijin; Wang, Tian; Fu, Fenghua

    2015-01-01

    The present study aimed to investigate the effects of oral administration of escin on acute inflammation and intestinal mucosal injury in animal models. The effects of escin on carrageenan-induced paw edema in a rat model of acute inflammation, cecal ligation and puncture (CLP) induced intestinal mucosal injury in a mouse model, were observed. It was shown that oral administration of escin inhibits carrageenan-induced paw edema and decreases the production of prostaglandin E2 (PGE2) and cyclooxygenase- (COX-) 2. In CLP model, low dose of escin ameliorates endotoxin induced liver injury and intestinal mucosal injury and increases the expression of tight junction protein claudin-5 in mice. These findings suggest that escin effectively inhibits acute inflammation and reduces intestinal mucosal injury in animal models. PMID:26199634

  18. Pathogenesis of Acute Kidney Injury: Foundation for Clinical Practice

    PubMed Central

    Kinsey, Gilbert R.; Okusa, Mark D.

    2011-01-01

    The pathogenesis of acute kidney injury (AKI) is complex, involving factors such as vasoconstriction, leukostasis, vascular congestion, cell death, and abnormal immune modulators and growth factors. Many targeted clinical therapies have failed, are inconclusive, or have yet to be tested. Given the complexity of the pathogenesis of AKI, it may be naïve to expect one therapeutic intervention would have success. Some examples of detrimental processes that can be blocked in pre-clinical models to improve kidney function and survival are apoptotic cell death in tubular epithelial cells, complement-mediated immune system activation, and impairment of cellular homeostasis and metabolism. Modalities with potential to reduce morbidity and mortality in AKI include vasodilators, growth factors, anti-inflammatory agents, and cell-based therapies. Pharmacological agents that target these diverse pathways are being used clinically for other indications. Using combinatorial approaches in future clinical trials may improve our ability to prevent and treat AKI. PMID:21530035

  19. The Adaptor Protein Myd88 Is a Key Signaling Molecule in the Pathogenesis of Irinotecan-Induced Intestinal Mucositis

    PubMed Central

    Wong, Deysi V. T.; Lima-Júnior, Roberto C. P.; Carvalho, Cibele B. M.; Borges, Vanessa F.; Wanderley, Carlos W. S.; Bem, Amanda X. C.; Leite, Caio A. V. G.; Teixeira, Maraiza A.; Batista, Gabriela L. P.; Silva, Rangel L.; Cunha, Thiago M.; Brito, Gerly A. C.; Almeida, Paulo R. C.; Cunha, Fernando Q.; Ribeiro, Ronaldo A.

    2015-01-01

    Intestinal mucositis is a common side effect of irinotecan-based anticancer regimens. Mucositis causes cell damage, bacterial/endotoxin translocation and production of cytokines including IL–1 and IL–18. These molecules and toll-like receptors (TLRs) activate a common signaling pathway that involves the Myeloid Differentiation adaptor protein, MyD88, whose role in intestinal mucositis is unknown. Then, we evaluated the involvement of TLRs and MyD88 in the pathogenesis of irinotecan-induced intestinal mucositis. MyD88-, TLR2- or TLR9-knockout mice and C57BL/6 (WT) mice were given either saline or irinotecan (75 mg/kg, i.p. for 4 days). On day 7, animal survival, diarrhea and bacteremia were assessed, and following euthanasia, samples of the ileum were obtained for morphometric analysis, myeloperoxidase (MPO) assay and measurement of pro-inflammatory markers. Irinotecan reduced the animal survival (50%) and induced a pronounced diarrhea, increased bacteremia, neutrophil accumulation in the intestinal tissue, intestinal damage and more than twofold increased expression of MyD88 (200%), TLR9 (400%), TRAF6 (236%), IL–1β (405%), IL–18 (365%), COX–2 (2,777%) and NF-κB (245%) in the WT animals when compared with saline-injected group (P<0.05). Genetic deletion of MyD88, TLR2 or TLR9 effectively controlled the signs of intestinal injury when compared with irinotecan-administered WT controls (P<0.05). In contrast to the MyD88-/- and TLR2-/- mice, the irinotecan-injected TLR9-/- mice showed a reduced survival, a marked diarrhea and an enhanced expression of IL–18 versus irinotecan-injected WT controls. Additionally, the expression of MyD88 was reduced in the TLR2-/- or TLR9-/- mice. This study shows a critical role of the MyD88-mediated TLR2 and TLR9 signaling in the pathogenesis of irinotecan-induced intestinal mucositis. PMID:26440613

  20. Human immunodeficiency virus-associated disruption of mucosal barriers and its role in HIV transmission and pathogenesis of HIV/AIDS disease.

    PubMed

    Tugizov, Sharof

    2016-01-01

    Oral, intestinal and genital mucosal epithelia have a barrier function to prevent paracellular penetration by viral, bacterial and other pathogens, including human immunodeficiency virus (HIV). HIV can overcome these barriers by disrupting the tight and adherens junctions of mucosal epithelia. HIV-associated disruption of epithelial junctions may also facilitate paracellular penetration and dissemination of other viral pathogens. This review focuses on possible molecular mechanisms of HIV-associated disruption of mucosal epithelial junctions and its role in HIV transmission and pathogenesis of HIV and acquired immune deficiency syndrome (AIDS). PMID:27583187

  1. Update on pathogenesis and clinical management of acute pancreatitis

    PubMed Central

    Cruz-Santamaría, Dulce M; Taxonera, Carlos; Giner, Manuel

    2012-01-01

    Acute pancreatitis (AP), defined as the acute nonbacterial inflammatory condition of the pancreas, is derived from the early activation of digestive enzymes found inside the acinar cells, with variable compromise of the gland itself, nearby tissues and other organs. So, it is an event that begins with pancreatic injury, elicits an acute inflammatory response, encompasses a variety of complications and generally resolves over time. Different conditions are known to induce this disorder, although the innermost mechanisms and how they act to develop the disease are still unknown. We summarize some well established aspects. A phase sequence has been proposed: etiology factors generate other conditions inside acinar cells that favor the AP development with some systemic events; genetic factors could be involved as susceptibility and modifying elements. AP is a disease with extremely different clinical expressions. Most patients suffer a mild and limited disease, but about one fifth of cases develop multi organ failure, accompanied by high mortality. This great variability in presentation, clinical course and complications has given rise to the confusion related to AP related terminology. However, consensus meetings have provided uniform definitions, including the severity of the illness. The clinical management is mainly based on the disease´s severity and must be directed to correct the underlying predisposing factors and control the inflammatory process itself. The first step is to determine if it is mild or severe. We review the principal aspects to be considered in this treatment, as reflected in several clinical practice guidelines. For the last 25 years, there has been a global increase in incidence of AP, along with many advances in diagnosis and treatment. However, progress in knowledge of its pathogenesis is scarce. PMID:22737590

  2. Oxidative Stress: An Essential Factor in the Pathogenesis of Gastrointestinal Mucosal Diseases

    PubMed Central

    Bhattacharyya, Asima; Chattopadhyay, Ranajoy; Mitra, Sankar

    2014-01-01

    Reactive oxygen species (ROS) are generated as by-products of normal cellular metabolic activities. Superoxide dismutase, glutathione peroxidase, and catalase are the enzymes involved in protecting cells from the damaging effects of ROS. ROS are produced in response to ultraviolet radiation, cigarette smoking, alcohol, nonsteroidal anti-inflammatory drugs, ischemia-reperfusion injury, chronic infections, and inflammatory disorders. Disruption of normal cellular homeostasis by redox signaling may result in cardiovascular, neurodegenerative diseases and cancer. ROS are produced within the gastrointestinal (GI) tract, but their roles in pathophysiology and disease pathogenesis have not been well studied. Despite the protective barrier provided by the mucosa, ingested materials and microbial pathogens can induce oxidative injury and GI inflammatory responses involving the epithelium and immune/inflammatory cells. The pathogenesis of various GI diseases including peptic ulcers, gastrointestinal cancers, and inflammatory bowel disease is in part due to oxidative stress. Unraveling the signaling events initiated at the cellular level by oxidative free radicals as well as the physiological responses to such stress is important to better understand disease pathogenesis and to develop new therapies to manage a variety of conditions for which current therapies are not always sufficient. PMID:24692350

  3. Role of duodenogastroesophageal reflux in the pathogenesis of esophageal mucosal injury and gastroesophageal reflux symptoms

    PubMed Central

    Xu, Xiao-rong; Li, Zhao-shen; Zou, Duo-wu; Xu, Guo-ming; Ye, Ping; Sun, Zhen-xing; Wang, Qing; Zeng, Yan-jun

    2006-01-01

    BACKGROUND AND AIM Patients with gastroesophageal reflux disease (GERD) usually suffer from acid reflux and duo-denogastroesophageal reflux (DGER) simultaneously. The question of whether DGER has an important effect on the development of GERD remains controversial. The aim of the present study was to investigate the role of DGER in the pathogenesis of GERD and its value for the diagnosis of nonerosive reflux disease (NERD). METHODS GERD was initially diagnosed using the reflux disease questionnaire. For further diagnosis, results of the upper gastrointestinal endoscopy (excluding a diagnosis of Barrett’s esophagus) were considered in conjunction with simultaneous 24 h esophageal pH and bilirubin monitoring. RESULTS According to endoscopic findings, 95 patients (43 men, 50±10 years of age) were divided into two groups: the reflux esophagitis (RE) group (n=51) and the NERD group (n=44). Three DGER parameters, the percentage of time with absorbance greater than 0.14, the total number of reflux episodes and the number of bile reflux episodes lasting longer than 5 min, were evaluated in the study. For the RE group, the values of the DGER parameters (19.05%±23.44%, 30.56±34.04 and 5.90±6.37, respectively) were significantly higher than those of the NERD group (7.26%±11.08%, 15.68±20.92 and 2.59±3.57, respectively, P<0.05 for all) but no significant difference was found in acid reflux. Of NERD patients, 18.5% were diagnosed with simple DGER. The positive diagnosis rate of NERD could be significantly elevated from 65.9% to 84.1% (P<0.05), if bilirubin monitoring was employed in diagnosis. CONCLUSIONS DGER may occur independently but plays an important role in the development of RE and GERD symptoms. Simultaneous 24 h esophageal pH and bilirubin monitoring is superior to simple pH monitoring in helping identify patients at risk for NERD. PMID:16482234

  4. Influence of plasma GSH level on acute radiation mucositis of the oral cavity

    SciTech Connect

    Bhattathiri, V.N.; Nair, M.K.; Sreelekha, T.T.; Sebastian, P.; Remani, P.; Chandini, R.; Vijayakumar, T. )

    1994-05-15

    The purpose of the study was to see how pretreatment plasma GSH level influences the severity of acute radiation mucositis of the oral cavity during therapeutic irradiation in patients with oral cancer. Thirteen patients with squamous cell circinoma of the oral cavity form the subject material. Radical radiotherapy (60 Gy in 25 fractions over 5 weeks) was given using telecobalt. Pretreatment plasma GSH level was measured by Beutler's method. The normal tissue reaction during radiotherapy was monitored and graded. The GSH levels ranged from 10.6-90.5 [mu]M/L (mean 30.6 [mu]M/L). Those who had higher GSH levels developed less severe mucositis. The mean GSH levels in the groups with different severity of reactions were: Grade 2 (four patients) = 50.7 [mu]M/L; Grade 3 (five patients) = 26.1 [mu]M/L; Grade 4 (two patients) = 20.4 [mu]M/L and Grade 5 (two patients) = 26.1 [mu]M/L; Grade 4 (two patients) = 20.4 [mu]M/L and Grade 5 (two patients) = 13.6 [mu]M/L. Plasma GSH estimation has the potential to predict individual sensitivity to acute radiation mucositis and may particularly be useful in hyperfractionated regimes. The study also affirms the radioprotective role of GSH and suggests that this effect is either due to protection against membrane lipid perodixation (since GSH does not enter the cell freely) or DNA damage (fractionated radiotherapy may permit freer entry of GSH into cell). 26 refs., 1 fig., 2 tabs.

  5. Pathogenesis and clinical presentation of acute heart failure.

    PubMed

    Ponikowski, Piotr; Jankowska, Ewa A

    2015-04-01

    Acute heart failure constitutes a heterogeneous clinical syndrome, whose pathophysiology is complex and not completely understood. Given the diversity of clinical presentations, several different pathophysiological mechanisms along with factors triggering circulatory decompensation are involved. This article discusses the available evidence on the pathophysiological phenomena attributed or/and associated with episodes of acute heart failure and describes different clinical profiles, which, from a clinical perspective, constitute a key element for therapeutic decision-making. PMID:25743769

  6. Acute gastroduodenal mucosal injury after cisplatin plus etoposide chemotherapy. Clinical and endoscopic study.

    PubMed

    Sartori, S; Nielsen, I; Maestri, A; Beltrami, D; Trevisani, L; Pazzi, P

    1991-01-01

    The effects on gastric and duodenal mucosa induced by cisplatin plus etoposide (PE) chemotherapy were investigated in 32 patients with lung cancer. They were submitted to gastroduodenoscopy before receiving cisplatin 100 mg/m2 (day 1) plus etoposide at a mean dose of 107 mg/m2 (days 1, 3 and 5). Endoscopic examination was repeated on day 8. Before chemotherapy, 22 patients showed normal endoscopic appearance and 10 minimal lesions (3 or fewer erosions). After chemotherapy, 16 remained normal, 1 had minimal lesions and 15 developed major lesions: 11 gastric or duodenal multiple erosions, 1 diffuse erosive gastritis, 2 gastric and 1 duodenal ulcer (p less than 0.001). No difference was observed in the number of vomiting episodes nor in severity of upper gastrointestinal symptoms between the patients who remained normal and those who developed mucosal injury. We conclude that PE chemotherapy can have a properly called gastroduodenal toxicity, leaving nausea and vomiting out which are rather due to central than peripheral mechanisms. Some trials are necessary to investigate which kind of drugs (H2-receptor blockers, sucralfate, prostaglandin E analogues) may be useful in preventing acute gastroduodenal mucosal injury induced by PE chemotherapy. PMID:1745480

  7. Protective Effects of the Traditional Herbal Formula Oryeongsan Water Extract on Ethanol-Induced Acute Gastric Mucosal Injury in Rats

    PubMed Central

    Jeon, Woo-Young; Lee, Mee-Young; Shin, In-Sik; Lim, Hye-Sun; Shin, Hyeun-Kyoo

    2012-01-01

    This study was performed to evaluate the protective effect and safety of Oryeongsan water extract (OSWE) on ethanol-induced acute gastric mucosal injury and an acute toxicity study in rats. Acute gastric lesions were induced via intragastric oral administration of absolute ethanol at a dose of 5 mL/kg. OSWE (100 and 200 mg/kg) was administered to rats 2 h prior to the oral administration of absolute ethanol. The stomach of animal models was opened and gastric mucosal lesions were examined. Gastric mucosal injuries were evaluated by measuring the levels of malondialdehyde (MDA), glutathione (GSH), and the activity of antioxidant enzymes. In the acute toxicity study, no adverse effects of OSWE were observed at doses up to 2000 mg/kg/day. Administration of OSWE reduced the damage by conditioning the gastric mucosa against ethanol-induced acute gastric injury, which included hemorrhage, hyperemia, and loss of epithelial cells. The level of MDA was reduced in OSWE-treated groups compared with the ethanol-induced group. Moreover, the level of GSH and the activity of antioxidant enzymes were significantly increased in the OSWE-treated groups. Our findings suggest that OSWE has a protective effect on the gastric mucosa against ethanol-induced acute gastric injury via the upregulation of antioxidant enzymes. PMID:23118790

  8. Pattern Analysis of Acute Mucosal Reactions in Patients With Head and Neck Cancer Treated With Conventional and Accelerated Irradiation

    SciTech Connect

    Wygoda, Andrzej Maciejewski, Boguslaw; Skladowski, Krzysztof; Hutnik, Marcin; Pilecki, Boleslaw; Golen, Maria; Rutkowski, Tomasz

    2009-02-01

    Purpose: To evaluate severity of acute mucosal reactions (AMR) caused by conventional (CF) and accelerated fractionation (AF) regimens using a modified Dische system and to analyze differences in incidence and severity of AMR according to frequency and regularity of scoring. Methods and Materials: Sixty-six consecutive patients (33 CF, 33 AF) with head and neck cancer irradiated with 5 fractions in 5 days per week (CF) or with 7 fractions in 7 days (AF) to a total dose of 70 Gy. A modified Dische system was used for daily quantitation of AMR during radiotherapy until complete healing. Results: Confluent mucositis (CM) was noted in 79% of patients in the CF group and 85% in the AF group. In 24% of the CF group and 18% of the AF group the CM presented a wave-like pattern. In 55% of CF and 67% of AF a classic triphasic pattern was noted. In 12 patients acute reactions did not transgress the level of spotted mucositis. The present study clearly shows that quantitation of the incidence and severity of acute mucosal effects strongly depends on frequent and regular scoring. A significant difference in the incidence of CM between the CF and AF groups was noted, mainly in weeks 4-6 of irradiation. When once-weekly irregular instead of daily scoring was evaluated, the incidence of CM was underestimated by approximately 20-36%. Conclusions: Acute mucosal reactions occur as a complex of morphologic and functional disorders with individual intensity, even among patients treated with the same fractionation regimen. In some cases they present a 'wave-like' pattern during irradiation. Therefore, precise quantitation of acute effects requires regular and frequent scoring.

  9. Initiation of ART during Early Acute HIV Infection Preserves Mucosal Th17 Function and Reverses HIV-Related Immune Activation

    PubMed Central

    Schuetz, Alexandra; Deleage, Claire; Sereti, Irini; Rerknimitr, Rungsun; Phanuphak, Nittaya; Phuang-Ngern, Yuwadee; Estes, Jacob D.; Sandler, Netanya G.; Sukhumvittaya, Suchada; Marovich, Mary; Jongrakthaitae, Surat; Akapirat, Siriwat; Fletscher, James L. K.; Kroon, Eugene; Dewar, Robin; Trichavaroj, Rapee; Chomchey, Nitiya; Douek, Daniel C.; O′Connell, Robert J.; Ngauy, Viseth; Robb, Merlin L.; Phanuphak, Praphan; Michael, Nelson L.; Excler, Jean-Louis; Kim, Jerome H.; de Souza, Mark S.; Ananworanich, Jintanat

    2014-01-01

    Mucosal Th17 cells play an important role in maintaining gut epithelium integrity and thus prevent microbial translocation. Chronic HIV infection is characterized by mucosal Th17 cell depletion, microbial translocation and subsequent immune-activation, which remain elevated despite antiretroviral therapy (ART) correlating with increased mortality. However, when Th17 depletion occurs following HIV infection is unknown. We analyzed mucosal Th17 cells in 42 acute HIV infection (AHI) subjects (Fiebig (F) stage I-V) with a median duration of infection of 16 days and the short-term impact of early initiation of ART. Th17 cells were defined as IL-17+ CD4+ T cells and their function was assessed by the co-expression of IL-22, IL-2 and IFNγ. While intact during FI/II, depletion of mucosal Th17 cell numbers and function was observed during FIII correlating with local and systemic markers of immune-activation. ART initiated at FI/II prevented loss of Th17 cell numbers and function, while initiation at FIII restored Th17 cell numbers but not their polyfunctionality. Furthermore, early initiation of ART in FI/II fully reversed the initially observed mucosal and systemic immune-activation. In contrast, patients treated later during AHI maintained elevated mucosal and systemic CD8+ T-cell activation post initiation of ART. These data support a loss of Th17 cells at early stages of acute HIV infection, and highlight that studies of ART initiation during early AHI should be further explored to assess the underlying mechanism of mucosal Th17 function preservation. PMID:25503054

  10. The influence of acute or chronic nicotine treatment on ethanol-induced gastric mucosal damage in rats.

    PubMed

    Cho, C H; Chen, B W; Hui, W M; Lam, S K

    1990-01-01

    The influences of acute or chronic nicotine pretreatment on ethanol-induced changes on gastric secretion, mucosal blood flow (GMBF), and glandular mucosal damage were studied in anesthetized rats. Ethanol administration decreased gastric acid secretion and GMBF, which were accompanied by a marked increase in gastric mucosal damage. Acute nicotine incubation 2 or 4 mg dose-dependently elevated both the titratable acid in the luminal solution and the gastric secretory volume; it also prevented the depressive action on GMBF and gastric mucosal damage in ethanol-treated animals. Chronic nicotine treatment for 10 days reduced the inhibitory action of ethanol on gastric acid secretion; the higher dose (25 micrograms/ml drinking water) potentiated the decrease of GMBF and the ulcerogenic property of ethanol. However, chronic treatment with the lower dose (5 micrograms/ml drinking water) had the opposite effects; it also markedly increased the gastric secretory volume. It is concluded that acute nicotine pretreatment elevates, whereas chronic nicotine pretreatment differentially affects GMBF. These effects could account for their protective or preventive actions on ethanol ulceration. The increase in nonacid gastric secretory volume by nicotine could partially explain its antiulcer effect. Furthermore, the acid secretory state of the stomach appears unrelated to the ulcerogenic property of ethanol. PMID:2295286

  11. Effect of low-power (He-Ne) laser on acute mucosal ulceration induced by indomethacin in rats

    NASA Astrophysics Data System (ADS)

    Djavid, Gholam-reza E.; Erfani, Rebecca; Amoohashemi, Nasim; Pazoki, Mahbobeh; Aghaee, Sanaz; Toroudi, Hamidreza P.

    2002-10-01

    Background: Low-level laser has been used for treatment of ulcer, as well as, pain relief and inflammatory processes. In the present work, the effect of low power laser on mucosal gastric ulceration-induced by indomethacin in rats has been investigated. Materials and Methods: 16 male Sprague Dawley rats were divided into control (8 rats) and laser exposed group (8 rats). After using ether for anesthesia, 30 mg/kg indomethacin was injected subcutaneously. Exposed stomachs received 30 J He-Ne laser. Five hours later animals were killed and their stomachs were checked and observed for presence of ulceration. Results and Discussion: Gastric mucosal ulceration index was significantly greater in the laser-exposed group than control group. (P=0.02) This experiment suggests that low power He-Ne laser intensified acute mucosal ulcer formation by indomethacin. Changes in the prostaglandin content ofthe stomach may be responsible for these results.

  12. Acute kidney injury by radiographic contrast media: pathogenesis and prevention.

    PubMed

    Andreucci, Michele; Faga, Teresa; Pisani, Antonio; Sabbatini, Massimo; Michael, Ashour

    2014-01-01

    It is well known that iodinated radiographic contrast media may cause kidney dysfunction, particularly in patients with preexisting renal impairment associated with diabetes. This dysfunction, when severe, will cause acute renal failure (ARF). We may define contrast-induced Acute Kidney Injury (AKI) as ARF occurring within 24-72 hrs after the intravascular injection of iodinated radiographic contrast media that cannot be attributed to other causes. The mechanisms underlying contrast media nephrotoxicity have not been fully elucidated and may be due to several factors, including renal ischaemia, particularly in the renal medulla, the formation of reactive oxygen species (ROS), reduction of nitric oxide (NO) production, and tubular epithelial and vascular endothelial injury. However, contrast-induced AKI can be prevented, but in order to do so, we need to know the risk factors. We have reviewed the risk factors for contrast-induced AKI and measures for its prevention, providing a long list of references enabling readers to deeply evaluate them both. PMID:25197639

  13. Acute Kidney Injury by Radiographic Contrast Media: Pathogenesis and Prevention

    PubMed Central

    Faga, Teresa; Pisani, Antonio; Michael, Ashour

    2014-01-01

    It is well known that iodinated radiographic contrast media may cause kidney dysfunction, particularly in patients with preexisting renal impairment associated with diabetes. This dysfunction, when severe, will cause acute renal failure (ARF). We may define contrast-induced Acute Kidney Injury (AKI) as ARF occurring within 24–72 hrs after the intravascular injection of iodinated radiographic contrast media that cannot be attributed to other causes. The mechanisms underlying contrast media nephrotoxicity have not been fully elucidated and may be due to several factors, including renal ischaemia, particularly in the renal medulla, the formation of reactive oxygen species (ROS), reduction of nitric oxide (NO) production, and tubular epithelial and vascular endothelial injury. However, contrast-induced AKI can be prevented, but in order to do so, we need to know the risk factors. We have reviewed the risk factors for contrast-induced AKI and measures for its prevention, providing a long list of references enabling readers to deeply evaluate them both. PMID:25197639

  14. Effect of diallyl disulfide on acute gastric mucosal damage induced by alcohol in rats.

    PubMed

    Lee, I-C; Baek, H-S; Kim, S-H; Moon, C; Park, S-H; Kim, S-H; Shin, I-S; Park, S-C; Kim, J-C

    2015-03-01

    This study investigated the gastroprotective effects of diallyl disulfide (DADS), a secondary organosulfur compound derived from garlic (Allium sativum L.) on experimental model of ethanol (EtOH)-induced gastric ulcer in rats. The antiulcerogenic activity of DADS was evaluated by gross/histopathological inspection, pro-inflammatory cytokines, and lipid peroxidation with antioxidant enzyme activities in the stomach. DADS (100 mg/kg) was administered by oral gavage 2 h prior to EtOH treatment (5 ml/kg). The animals were killed 1 h after receiving EtOH treatment. Pretreatment with DADS attenuated EtOH-induced gastric mucosal injury, as evidenced by decreased severity of hemorrhagic lesions and gastric ulcer index upon visual inspection. DADS also prevented histopathological alterations and gastric apoptotic changes caused by EtOH. An increase in tumor necrosis factor-α (TNF-α) and inducible nitric oxide synthase was observed in the gastric tissues of EtOH-treated rats that coincided with increased serum TNF-α and interleukin 6 levels. In contrast, DADS effectively suppressed production of pro-inflammatory mediators induced by EtOH. Furthermore, DADS prevented the formation of gastric malondialdehyde and the depletion of reduced glutathione content and restored antioxidant enzyme activities, such as catalase, glutathione peroxidase, and glutathione reductase in the gastric tissues of EtOH-treated rats. These results indicate that DADS prevents gastric mucosal damage induced by acute EtOH administration in rats and that the protective effects of DADS may be due to its potent antioxidant and anti-inflammatory activities. PMID:24972622

  15. Reduced gastric acid production in burn shock period and its significance in the prevention and treatment of acute gastric mucosal lesions.

    PubMed

    Zhu, Li; Yang, Zhong-Cheng; Li, Ao; Cheng, De-Chang

    2000-02-01

    AIM:To investigate the changes of gastric acid production and its mechanism in shock period of severe burn in rats.METHODS:A rat model with 30% TBSA full thickness burn injury was employed and the gastric acid production,together with gastric mucosal blood flow (GMBF) and energy charge (EC) were measured serially within 48h postburn.RESULTS:The gastric acid production in the acute shock period was markedly inhibited after severe burn injury.At the 3rd h postburn,the gastric juice volume, total acidity and acid output were already significantly decreased (P < 0.01 =, and reached the lowest point, 0.63mL/L ± 0.20mL/L, 10.81mmol/L ± 2.58mmol/L and 2.23mmol/h ± 0.73mmol/h respectively, at the 12th h postburn. Although restored to some degree 24h after thermal injury, the variables above were still statistically lower, compared with those of control animals at the 48th h postburn. The GMBF and EC were also significantly reduced after severe burns, consistent with the trend of gastric acid production changes.CONCLUSION:Gastric acid production, as well as GMBF and EC was predominantly decreased in the early postburn stage, suggesting that gastric mucosal ischemia and hypoxia with resultant disturbance in energy metabolism, but not gastric acid proper, might be the decisive factor in the pathogenesis of AGML after thermal injury, and that the preventive use of anti-acid drugs during burn shock period was unreasonable in some respects. Therefore, taking effective measures to improve gastric mucosal blood perfusion as early as possible postburn might be more preferable for the AGML prevention and treatment. PMID:11819529

  16. The acute lymphoblastic leukemia of Down Syndrome - Genetics and pathogenesis.

    PubMed

    Izraeli, Shai

    2016-03-01

    Children with Down Syndrome (DS) are at markedly increased risk for acute lymphoblastic leukemia (ALL). The ALL is of B cell precursor (BCP) phenotype. T-ALL is only rarely diagnosed as well as infant leukemia. Gene expression profiling and cytogenetics suggest that DS-ALL is an heterogeneous disease. More than half of the leukemias are characterized by aberrant expression of the thymic stromal lymphopoietin (TSLP) receptor CRLF2 caused by genomic rearrangements. These rearrangements are often associated with somatic activating mutations in the receptors or in the downstream components of the JAK-STAT pathway. The activation of JAK-STAT pathway suggests that targeted therapy with JAK or downstream inhibitors may be effective for children with DS-ALL. The basis of the increased risk of BCP-ALL and in particular of the CRLF2 aberrations is presently unknown. Neither is it known which genes on the trisomic chromosome 21 are involved. PMID:26631987

  17. The role of parvovirus B19 and the immune response in the pathogenesis of acute leukemia.

    PubMed

    Kerr, Jonathan R; Mattey, Derek L

    2015-05-01

    In this article, we review the evidence suggesting a possible role for B19 virus in the pathogenesis of a subset of cases of acute leukemia. Human parvovirus B19 infection may complicate the clinical course of patients with acute leukemia and may also precede the development of acute leukemia by up to 180 days. Parvovirus B19 targets erythroblasts in the bone marrow and may cause aplastic crisis in patients with shortened-red cell survival. Aplastic crisis represents a prodrome of acute lymphoblastic leukemia in 2% patients. There is a significant overlap between those HLA classes I and II alleles that are associated with a vigorous immune response and development of symptoms during B19 infection and those HLA alleles that predispose to development of acute leukemia. Acute symptomatic B19 infection is associated with low circulating IL-10 consistent with a vigorous immune response; deficient IL-10 production at birth was recently found to be associated with subsequent development of acute leukemia. Anti-B19 IgG has been associated with a particular profile of methylation of human cancer genes in patients with acute leukemia, suggesting an additional hit and run mechanism. The proposed role for parvovirus B19 in the pathogenesis of acute leukemia fits well with the delayed infection hypothesis and with the two-step mutation model, which describes carriage of the first mutation prior to birth, followed by suppression of hematopoiesis, which allows rapid proliferation of cells harboring the first mutation, acquisition of a second activating mutation, and expansion of cells carrying both mutations, resulting in acute leukemia. PMID:25855476

  18. Pathogenesis of acute ischemic mitral regurgitation in three dimensions.

    PubMed

    Gorman, R C; McCaughan, J S; Ratcliffe, M B; Gupta, K B; Streicher, J T; Ferrari, V A; St John-Sutton, M G; Bogen, D K; Edmunds, L H

    1995-04-01

    Changes in the geometric and intravalvular relationships between subunits of the ovine mitral valve were measured before and after acute posterior wall myocardial infarction in three dimensions by means of sonomicrometry array localization. In 13 sheep, nine sonomicrometer transducers were attached around the mitral anulus and to the tip and base of each papillary muscle. Five additional transducers were placed on the epicardium. Snares were placed around three branches of the circumflex coronary artery. One to 2 weeks later, echocardiograms, dimension measurements, and left ventricular pressures were obtained before and after the coronary arteries were occluded. Data were obtained from seven sheep. Coronary occlusion infarcted 32% of the posterior left ventricle and produced 2 to 3+ mitral regurgitation by Doppler color flow mapping. Multidimensional scaling of dimension measurements obtained from sonomicrometry transducers produced three-dimensional spatial coordinates of each transducer location throughout the cardiac cycle before and after infarction and onset of mitral regurgitation. After posterior infarction, the mitral anulus enlarges asymmetrically along the posterior anulus, and the tip of the posterior papillary muscle moves 1.5 +/- 0.3 mm closer to the posterior commissure at end-systole. The posterior papillary muscle also elongates 1.9 +/- 0.3 mm at end-systole. The left ventricle enlarges asymmetrically and ventricular torsion along the long axis changes. The development of postinfarction mitral regurgitation appears to be the consequence of multiple small changes in ventricular shape and contractile deformation and in the spatial relationship of mitral valvular subunits. PMID:7715215

  19. Gastroprotective activity of Nigella sativa L oil and its constituent, thymoquinone against acute alcohol-induced gastric mucosal injury in rats

    PubMed Central

    Kanter, Mehmet; Demir, Halit; Karakaya, Cengiz; Ozbek, Hanefi

    2005-01-01

    AIM: To evaluate the role of reactive oxygen species in the pathogenesis of acute ethanol-induced gastric mucosal lesions and the effect of Nigella sativa L oil (NS) and its constituent thymoquinone (TQ) in an exper-imental model. METHODS: Male Wistar albino rats were assigned into 4 groups. Control group was given physiologic saline orally (10 mL/kg body weight) as the vehicle (gavage); ethanol group was administrated 1 mL (per rat) absolute alcohol by gavage; the third and fourth groups were given NS (10 mL/kg body weight) and TQ (10 mg/kg body weight p.o) respectively 1 h prior to alcohol intake. One hour after ethanol administration, stomach tissues were excised for macroscopic examination and biochemical analysis. RESULTS: NS and TQ could protect gastric mucosa against the injurious effect of absolute alcohol and promote ulcer healing as evidenced from the ulcer index (UI) values. NS prevented alcohol-induced increase in thiobarbituric acid-reactive substances (TBARS), an index of lipid peroxidation. NS also increased gastric glutathione content (GSH), enzymatic activities of gastric superoxide dismutase (SOD) and glutathione-S-transferase (GST). Likewise, TQ protected against the ulcerating effect of alcohol and mitigated most of the biochemical adverse effects induced by alcohol in gastric mucosa, but to a lesser extent than NS. Neither NS nor TQ affected catalase activity in gastric tissue. CONCLUSION: Both NS and TQ, particularly NS can partly protect gastric mucosa from acute alcohol-induced mucosal injury, and these gastroprotective effects might be induced, at least partly by their radical scavenging activity. PMID:16425361

  20. Prediction of Acute Radiation Mucositis using an Oral Mucosal Dose Surface Model in Carbon Ion Radiotherapy for Head and Neck Tumors

    PubMed Central

    Musha, Atsushi; Shimada, Hirofumi; Shirai, Katsuyuki; Saitoh, Jun-ichi; Yokoo, Satoshi; Chikamatsu, Kazuaki; Ohno, Tatsuya; Nakano, Takashi

    2015-01-01

    Purpose To evaluate the dose-response relationship for development of acute radiation mucositis (ARM) using an oral mucosal dose surface model (OMDS-model) in carbon ion radiotherapy (C-ion RT) for head and neck tumors. Methods Thirty-nine patients receiving C-ion RT for head and neck cancer were evaluated for ARM (once per week for 6 weeks) according to the Common Terminology Criteria for Adverse Events (CTCAE), version 4.0, and the Radiation Therapy Oncology Group (RTOG) scoring systems. The irradiation schedule typically used was 64 Gy [relative biological effectiveness (RBE)] in 16 fractions for 4 weeks. Maximum point doses in the palate and tongue were compared with ARM in each patient. Results The location of the ARM coincided with the high-dose area in the OMDS-model. There was a clear dose-response relationship between maximum point dose and ARM grade assessed using the RTOG criteria but not the CTCAE. The threshold doses for grade 2–3 ARM in the palate and tongue were 43.0 Gy(RBE) and 54.3 Gy(RBE), respectively. Conclusions The OMDS-model was useful for predicting the location and severity of ARM. Maximum point doses in the model correlated well with grade 2–3 ARM. PMID:26512725

  1. Divergent mucosal and systemic responses in children in response to acute otitis media.

    PubMed

    Verhoeven, D; Pichichero, M E

    2014-10-01

    Acute otitis media (AOM), induced by respiratory bacteria, is a significant cause of children seeking medical attention worldwide. Some children are highly prone to AOMs, suffering three to four recurrent infections per year (prone). We previously determined that this population of children could have diminished anti-bacterial immune responses in peripheral blood that could fail to limit bacterial colonization in the nasopharynx (NP). Here, we examined local NP and middle ear (ME) responses and compared them to peripheral blood to examine whether the mucosa responses were similar to the peripheral blood responses. Moreover, we examined differences in effector cytokine responses between these two populations in the NP, ME and blood compartments at the onset of an AOM caused by either Streptococcus pneumoniae or non-typeable Haemophilus influenzae. We found that plasma effector cytokines patterned antigen-recall responses of CD4 T cells, with lower responses detected in prone children. ME cytokine levels did not mirror blood, but were more similar to the NP. Interferon (IFN)-γ and interleukin (IL)-17 in the NP were similar in prone and non-prone children, while IL-2 production was higher in prone children. The immune responses diverged in the mucosal and blood compartments at the onset of a bacterial ME infection, thus highlighting differences between local and systemic immune responses that could co-ordinate anti-bacterial immune responses in young children. PMID:24889648

  2. Trypanosoma cruzi Entrance through Systemic or Mucosal Infection Sites Differentially Modulates Regional Immune Response Following Acute Infection in Mice

    PubMed Central

    de Meis, Juliana; Barreto de Albuquerque, Juliana; Silva dos Santos, Danielle; Farias-de-Oliveira, Désio Aurélio; Berbert, Luiz Ricardo; Cotta-de-Almeida, Vinícius; Savino, Wilson

    2013-01-01

    Acute Chagas disease is characterized by a systemic infection that leads to the strong activation of the adaptive immune response. Outbreaks of oral contamination by the infective protozoan Trypanosoma cruzi are frequent in Brazil and other Latin American countries, and an increased severity of clinical manifestations and mortality is observed in infected patients. These findings have elicited questions about the specific responses triggered after T. cruzi entry via mucosal sites, possibly modulating local immune mechanisms, and further impacting regional and systemic immunity. Here, we provide evidence for the existence of differential lymphoid organ responses in experimental models of acute T. cruzi infection. PMID:23898334

  3. Antibody blockade of IL-17 family cytokines in immunity to acute murine oral mucosal candidiasis.

    PubMed

    Whibley, Natasha; Tritto, Elaine; Traggiai, Elisabetta; Kolbinger, Frank; Moulin, Pierre; Brees, Dominique; Coleman, Bianca M; Mamo, Anna J; Garg, Abhishek V; Jaycox, Jillian R; Siebenlist, Ulrich; Kammüller, Michael; Gaffen, Sarah L

    2016-06-01

    Antibodies targeting IL-17A or its receptor, IL-17RA, are approved to treat psoriasis and are being evaluated for other autoimmune conditions. Conversely, IL-17 signaling is critical for immunity to opportunistic mucosal infections caused by the commensal fungus Candida albicans, as mice and humans lacking the IL-17R experience chronic mucosal candidiasis. IL-17A, IL-17F, and IL-17AF bind the IL-17RA-IL-17RC heterodimeric complex and deliver qualitatively similar signals through the adaptor Act1. Here, we used a mouse model of acute oropharyngeal candidiasis to assess the impact of blocking IL-17 family cytokines compared with specific IL-17 cytokine gene knockout mice. Anti-IL-17A antibodies, which neutralize IL-17A and IL-17AF, caused elevated oral fungal loads, whereas anti-IL-17AF and anti-IL-17F antibodies did not. Notably, there was a cooperative effect of blocking IL-17A, IL-17AF, and IL-17F together. Termination of anti-IL-17A treatment was associated with rapid C. albicans clearance. IL-17F-deficient mice were fully resistant to oropharyngeal candidiasis, consistent with antibody blockade. However, IL-17A-deficient mice had lower fungal burdens than anti-IL-17A-treated mice. Act1-deficient mice were much more susceptible to oropharyngeal candidiasis than anti-IL-17A antibody-treated mice, yet anti-IL-17A and anti-IL-17RA treatment caused equivalent susceptibilities. Based on microarray analyses of the oral mucosa during infection, only a limited number of genes were associated with oropharyngeal candidiasis susceptibility. In sum, we conclude that IL-17A is the main cytokine mediator of immunity in murine oropharyngeal candidiasis, but a cooperative relationship among IL-17A, IL-17AF, and IL-17F exists in vivo. Susceptibility displays the following hierarchy: IL-17RA- or Act1-deficiency > anti-IL-17A + anti-IL-17F antibodies > anti-IL-17A or anti-IL-17RA antibodies > IL-17A deficiency. PMID:26729813

  4. Methotrexate-induced mucositis in acute leukemia patients is not associated with the MTHFR 677T allele in Mexico.

    PubMed

    Ruiz-Argüelles, Guillermo J; Coconi-Linares, Lucia Nancy; Garcés-Eisele, Javier; Reyes-Núñez, Virginia

    2007-10-01

    Methylenetetrahydrofolate reductase (MTHFR) has two common variants with reduced activity due to polymorphisms at nucleotides 677 and 1298. Both affect folate metabolism and thus remethylation of homocysteine, but are also thought to affect nucleotide synthesis and DNA methylation. Methotrexate (MTX), which interrupts folate metabolism, is used in the treatment of a variety of diseases including acute lymphoblastic leukemia (ALL), but exerts in some patients toxic effects on fast dividing tissues such as mucosal epithelia. The enhanced toxicity may be due to cooperative effects between MTX and MTHFR variants. Accordingly, it has been reported that carrying the 677T allele of the MTHFR is a risk factor for MTX-associated mucositis. As in the Mexican population, which is characterized by a high prevalence of the 677T MTHFR variant, several of its commonly associated defects have not been observed, we investigated the relationship between MTX toxicity and the 677T allele. Out of 28 patients with ALL (CC: 2, CT: 10, TT: 16), 16 had episodes of MTX-associated mucositis (CC: 0, CT: 6, TT: 10). Neither at the gene level nor at the genotype level was a significant association with mucositis found. It may be postulated that the risk of higher MTX toxicity in patients with decreased MTHFR activity could be neutralized by the normally folate rich diet in Mexico. PMID:17891601

  5. Spatiotemporal interplay of severe acute respiratory syndrome coronavirus and respiratory mucosal cells drives viral dissemination in rhesus macaques.

    PubMed

    Liu, L; Wei, Q; Nishiura, K; Peng, J; Wang, H; Midkiff, C; Alvarez, X; Qin, C; Lackner, A; Chen, Z

    2016-07-01

    Innate immune responses have a critical role in the control of early virus replication and dissemination. It remains unknown, however, how severe acute respiratory syndrome coronavirus (SARS-CoV) evades respiratory innate immunity to establish a systemic infection. Here we show in Chinese macaques that SARS-CoV traversed the mucosa through the respiratory tract within 2 days, resulting in extensive mucosal infiltration by T cells, MAC387(+), and CD163(+) monocytes/macrophages followed by limited viral replication in the lung but persistent viral shedding into the upper airway. Mucosal monocytes/macrophages sequestered virions in intracellular vesicles together with infected Langerhans cells and migrated into the tonsils and/or draining lymph nodes within 2 days. In lymphoid tissues, viral RNA and proteins were detected in infected monocytes upon differentiation into dendritic cells (DCs) within 3 days. Systemic viral dissemination was observed within 7 days. This study provides a comprehensive overview of the spatiotemporal interactions of SARS-CoV, monocytes/macrophages, and the DC network in mucosal tissues and highlights the fact that, while these innate cells contribute to viral clearance, they probably also serve as shelters and vehicles to provide a mechanism for the virus to escape host mucosal innate immunity and disseminate systemically. PMID:26647718

  6. Acute bovine viral diarrhea associated with extensive mucosal lesions, high morbidity, and mortality in a commercial feedlot.

    PubMed

    Hessman, Bill E; Sjeklocha, David B; Fulton, Robert W; Ridpath, Julia F; Johnson, Bill J; McElroy, Diana R

    2012-03-01

    In 2008, a northwest Texas feedlot underwent an outbreak of Bovine viral diarrhea virus (BVDV) causing high morbidity and mortality involving 2 lots of calves (lots A and B). Severe mucosal surface lesions were observed grossly in the oral cavity, larynx, and esophagus. Mucosal lesions varied from small (1-3 mm) infrequent mucosal ulcerations to large (5 mm to 1 cm) and coalescing ulcerations. Necrotic debris was present in ulcerations of some mortalities with some having plaque-like debris, but other mortalities presented more proliferative lesions. A calf persistently infected with BVDV arrived with one lot and the isolated virus was genotyped as BVDV-1b. Identical BVDV-1b strains were isolated from 2 other mortalities. A BVDV-2a genotype was also isolated in this outbreak. This genotype was identical to all BVDV-2a strains isolated in both lots. Serum samples were collected from exposed and unexposed animals and tested for antibodies for multiple viral pathogens. Seropositivity ranged from zero percent for calicivirus to 100% positive to Pseudocowpox virusx. At the end of the feeding period, the morbidity and mortality for the 2 lots involved was 76.2% and 30.8%, respectively, for lot A, and 49.0% and 5.6%, respectively, for lot B. Differential diagnoses included vesicular stomatitis viruses, Bovine papular stomatitis virus, and Foot-and-mouth disease virus. Based on the present case, acute BVDV should be considered when mucosal lesions are observed grossly. PMID:22379057

  7. Mucosal immunization with PsaA protein, using chitosan as a delivery system, increases protection against acute otitis media and invasive infection by Streptococcus pneumoniae.

    PubMed

    Xu, J-H; Dai, W-J; Chen, B; Fan, X-Y

    2015-03-01

    As infection with Streptococcus pneumoniae (mainly via the mucosal route) is a leading cause of acute otitis media, sinus and bacterial pneumonia, the mucosal immunity plays an important role in the prevention of pneumococcal diseases. Therefore, intranasal vaccination may be an effective immunization strategy, but requires appropriate mucosal vaccine delivery systems. In this work, chitosan was used as a mucosal delivery system to form chitosan-PsaA nanoparticles based on ionotropic gelation methods and used to immunize BALB/c mice intranasally. Compared to mice immunized with naked PsaA, levels of IFN-γ, IL-17A and IL-4 in spleen lymphocytes, the systemic (IgG in serum) and mucosal (IgA in mucosal lavage) specific antibodies were enhanced significantly in mice inoculated with chitosan-PsaA. Furthermore, increased protection against acute otitis media following middle ear challenge with pneumococcus serotype 14, and improved survival following intraperitoneal challenge with pneumococcus serotype 3 or serotype 14, was found in the mice immunized with chitosan-PsaA nanoparticles. Thus, intranasal immunization with chitosan-PsaA can successfully induce mucosal and systemic immune responses and increase protection against pneumococcal acute otitis media and invasive infections. Hence, intranasal immunization with PsaA protein, based on chitosan as a delivery system, is an efficient immunization strategy for preventing pneumococcal infections. PMID:25565478

  8. The effect of Aloe vera A. Berger (Liliaceae) on gastric acid secretion and acute gastric mucosal injury in rats.

    PubMed

    Yusuf, Sadiq; Agunu, Abdulkarim; Diana, Mshelia

    2004-07-01

    The effect of varying doses of ethanol extract of Aloe vera (Liliaceae) on acute gastric mucosal lesions induced by 0.6 M HCl and acid output was studied in the pylorus ligated and lumen perfuse rats, respectively. Acid secretion was determined by titration of the collected gastric juice to pH 7.0. Intraperitoneal injection of Aloe vera, dose dependently inhibited gastric acid secretion. The plant was more active as a gastroprotective agent at lower concentration against mucosal injury induced by 0.6 M HCl. In conclusion, Aloe vera is endowed with gastric acid anti-secretory activity and could protect the gastric mucosa at low concentrations against injurious agents. PMID:15182901

  9. Assessment of the effect of local application of amifostine on acute radiation-induced oral mucositis in guinea pigs.

    PubMed

    Li, Chang Jiang; Wang, Sheng Zi; Wang, Shu Yi; Zhang, Yan Ping

    2014-09-01

    The aim of present study was to assess the radioprotective effects of the local application of amifostine to treat acute buccal mucositis in guinea pigs. A total of 32 guinea pigs were randomized into four groups: (Group A) topically administered 50 mg of amifostine plus radiotherapy (RT); (Group B) 100 mg amifostine plus RT; (Group C) normal saline plus RT; and (Group D) normal saline plus sham RT. The opportunity for administration was 15 min before irradiation. When administered, the cotton pieces that had been soaked with 0.5 ml amifostine solution or saline were applied gently on the buccal mucosa of each guinea pig for 30 min. The animals in Groups A, B and C were irradiated individually with a single dose of 30 Gy to the bilateral buccal mucosa. Eight days after irradiation, the animals were scored macroscopically; they were then euthanized, and the buccal mucosal tissues were processed for hematoxylin-eosin staining and ICAM-1 immunohistochemical analysis. In Groups A and B, the mean macroscopic scores were 2.9 ± 0.6 and 2.4 ± 1.1, respectively. There was no significant difference between the two groups (P > 0.05). However, when they were separately compared with Group C (4.4 ± 0.7), a noticeable difference was obtained (P < 0.05). No mucositis was observed in Group D. Comparisons of the expression of ICAM-1 were in agreement with the macroscopic data. Histologically, superficial erosion, exudate and ulcer formation were all observed in the RT groups; only the severity and extent were different. The microscopic observations in the amifostine-treated groups were better than in Group C. The results demonstrated that topical administration of amifostine to the oral mucosa is effective treatment of acute radiation-induced mucositis. PMID:24706999

  10. Pathogenesis of acute and chronic lung injury induced by foreign compounds

    SciTech Connect

    Witschi, H.P.; Lindenschmidt, R.C.

    1984-01-01

    The lung may become damaged by both airborne or bloodborne agents. Mechanisms implicated in the pathogenesis of lung injury include formation of highly reactive metabolites formed by pulmonary mixed function oxidases or formation of free oxygen radicals. Acute and chronic damage can be evaluated by several methods, such as histology and quantitative morphometry, non-invasive and non-destructive respiratory function tests, and with biochemical techniques that include measuring lavage enzyme levels or quantitating the presence of macromolecules such as collagen. In addition, cell kinetics provide an additional method to explore events following lung damage. 34 references.

  11. Role of inflammation and infection in the pathogenesis of human acute liver failure: Clinical implications for monitoring and therapy

    PubMed Central

    Donnelly, Mhairi C; Hayes, Peter C; Simpson, Kenneth J

    2016-01-01

    Acute liver failure is a rare and devastating clinical condition. At present, emergency liver transplantation is the only life-saving therapy in advanced cases, yet the feasibility of transplantation is affected by the presence of systemic inflammation, infection and resultant multi-organ failure. The importance of immune dysregulation and acquisition of infection in the pathogenesis of acute liver failure and its associated complications is now recognised. In this review we discuss current thinking regarding the role of infection and inflammation in the pathogenesis of and outcome in human acute liver failure, the implications for the management of such patients and suggest directions for future research. PMID:27468190

  12. Role of inflammation and infection in the pathogenesis of human acute liver failure: Clinical implications for monitoring and therapy.

    PubMed

    Donnelly, Mhairi C; Hayes, Peter C; Simpson, Kenneth J

    2016-07-14

    Acute liver failure is a rare and devastating clinical condition. At present, emergency liver transplantation is the only life-saving therapy in advanced cases, yet the feasibility of transplantation is affected by the presence of systemic inflammation, infection and resultant multi-organ failure. The importance of immune dysregulation and acquisition of infection in the pathogenesis of acute liver failure and its associated complications is now recognised. In this review we discuss current thinking regarding the role of infection and inflammation in the pathogenesis of and outcome in human acute liver failure, the implications for the management of such patients and suggest directions for future research. PMID:27468190

  13. Coronavirus Pathogenesis and the Emerging Pathogen Severe Acute Respiratory Syndrome Coronavirus

    PubMed Central

    Weiss, Susan R.; Navas-Martin, Sonia

    2005-01-01

    Coronaviruses are a family of enveloped, single-stranded, positive-strand RNA viruses classified within the Nidovirales order. This coronavirus family consists of pathogens of many animal species and of humans, including the recently isolated severe acute respiratory syndrome coronavirus (SARS-CoV). This review is divided into two main parts; the first concerns the animal coronaviruses and their pathogenesis, with an emphasis on the functions of individual viral genes, and the second discusses the newly described human emerging pathogen, SARS-CoV. The coronavirus part covers (i) a description of a group of coronaviruses and the diseases they cause, including the prototype coronavirus, murine hepatitis virus, which is one of the recognized animal models for multiple sclerosis, as well as viruses of veterinary importance that infect the pig, chicken, and cat and a summary of the human viruses; (ii) a short summary of the replication cycle of coronaviruses in cell culture; (iii) the development and application of reverse genetics systems; and (iv) the roles of individual coronavirus proteins in replication and pathogenesis. The SARS-CoV part covers the pathogenesis of SARS, the developing animal models for infection, and the progress in vaccine development and antiviral therapies. The data gathered on the animal coronaviruses continue to be helpful in understanding SARS-CoV. PMID:16339739

  14. Gastroprotection Studies of Schiff Base Zinc (II) Derivative Complex against Acute Superficial Hemorrhagic Mucosal Lesions in Rats

    PubMed Central

    Golbabapour, Shahram; Gwaram, Nura Suleiman; Hassandarvish, Pouya; Hajrezaie, Maryam; Kamalidehghan, Behnam; Abdulla, Mahmood Ameen; Ali, Hapipah Mohd; Hadi, A. Hamid A; Majid, Nazia Abdul

    2013-01-01

    Background The study was carried out to assess the gastroprotective effect of the zinc (II) complex against ethanol-induced acute hemorrhagic lesions in rats. Methodology/Principal Finding The animals received their respective pre-treatments dissolved in tween 20 (5% v/v), orally. Ethanol (95% v/v) was orally administrated to induce superficial hemorrhagic mucosal lesions. Omeprazole (5.790×10−5 M/kg) was used as a reference medicine. The pre-treatment with the zinc (II) complex (2.181×10−5 and 4.362×10−5 M/kg) protected the gastric mucosa similar to the reference control. They significantly increased the activity levels of nitric oxide, catalase, superoxide dismutase, glutathione and prostaglandin E2, and decreased the level of malondialdehyde. The histology assessments confirmed the protection through remarkable reduction of mucosal lesions and increased the production of gastric mucosa. Immunohistochemistry and western blot analysis indicated that the complex might induced Hsp70 up-regulation and Bax down-regulation. The complex moderately increased the gastroprotectiveness in fine fettle. The acute toxicity approved the non-toxic characteristic of the complex (<87.241×10−5 M/kg). Conclusion/Significance The gastroprotective effect of the zinc (II) complex was mainly through its antioxidant activity, enzymatic stimulation of prostaglandins E2, and up-regulation of Hsp70. The gastric wall mucus was also a remarkable protective mechanism. PMID:24058648

  15. Normal tissue complication probability (NTCP) modelling using spatial dose metrics and machine learning methods for severe acute oral mucositis resulting from head and neck radiotherapy

    PubMed Central

    Dean, Jamie A; Wong, Kee H; Welsh, Liam C; Jones, Ann-Britt; Schick, Ulrike; Newbold, Kate L; Bhide, Shreerang A; Harrington, Kevin J; Nutting, Christopher M; Gulliford, Sarah L

    2016-01-01

    Background and Purpose Severe acute mucositis commonly results from head and neck (chemo)radiotherapy. A predictive model of mucositis could guide clinical decision-making and inform treatment planning. We aimed to generate such a model using spatial dose metrics and machine learning. Material and Methods Predictive models of severe acute mucositis were generated using radiotherapy dose (dose-volume and spatial dose metrics) and clinical data. Penalised logistic regression, support vector classification and random forest classification (RFC) models were generated and compared. Internal validation was performed (with 100-iteration cross-validation), using multiple metrics, including area under the receiver operating characteristic curve (AUC) and calibration slope, to assess performance. Associations between covariates and severe mucositis were explored using the models. Results The dose-volume-based models (standard) performed equally to those incorporating spatial information. Discrimination was similar between models, but the RFCstandard had the best calibration. The mean AUC and calibration slope for this model were 0.71 (s.d.=0.09) and 3.9 (s.d.=2.2), respectively. The volumes of oral cavity receiving intermediate and high doses were associated with severe mucositis. Conclusions The RFCstandard model performance is modest-to-good, but should be improved, and requires external validation. Reducing the volumes of oral cavity receiving intermediate and high doses may reduce mucositis incidence. PMID:27240717

  16. Tonometry revisited: perfusion-related, metabolic, and respiratory components of gastric mucosal acidosis in acute cardiorespiratory failure.

    PubMed

    Jakob, Stephan M; Parviainen, Ilkka; Ruokonen, Esko; Kogan, Alexander; Takala, Jukka

    2008-05-01

    Mucosal pH (pHi) is influenced by local perfusion and metabolism (mucosal-arterial pCO2 gradient, DeltapCO2), systemic metabolic acidosis (arterial bicarbonate), and respiration (arterial pCO2). We determined these components of pHi and their relation to outcome during the first 24 h of intensive care. We studied 103 patients with acute respiratory or circulatory failure (age, 63+/-2 [mean+/-SEM]; Acute Physiology and Chronic Health Evaluation II score, 20+/-1; Sequential Organ Failure Assessment score, 8+/-0). pHi, and the effects of bicarbonate and arterial and mucosal pCO2 on pHi, were assessed at admission, 6, and 24 h. pHi was reduced (at admission, 7.27+/-0.01) due to low arterial bicarbonate and increased DeltapCO2. Low pHi (<7.32) at admission (n=58; mortality, 29% vs. 13% in those with pHi>or=7.32 at admission; P=0.061) was associated with an increased DeltapCO2 in 59% of patients (mortality, 47% vs. 4% for patients with low pHi and normal DeltapCO2; P=0.0003). An increased versus normal DeltapCO2, regardless of pHi, was associated with increased mortality at admission (51% vs. 5%; P<0.0001; n=39) and at 6 h (34% vs. 13%; P=0.016; n=45). A delayed normalization or persistently low pHi (n=47) or high DeltapCO2 (n=25) was associated with high mortality (low pHi [34%] vs. high DeltapCO2 [60%]; P=0.046). In nonsurvivors, hypocapnia increased pHi at baseline, 6, and 24 h (all Pmucosal acidosis. Inadequate tissue perfusion may persist despite stable hemodynamics and contributes to poor outcome. PMID:18004228

  17. Beta-defensin 1 plays a role in acute mucosal defense to Candida albicans

    PubMed Central

    Tomalka, Jeffrey; Azodi, Elaheh; Narra, Hema P.; Patel, Krupen; O’Neill, Samantha; Cardwell, Cisley; Hall, Brian A.; Wilson, James M.; Hise, Amy G.

    2015-01-01

    Candida is an opportunistic fungal pathogen that colonizes the mucosal tract of humans. Pathogenic infection occurs in the presence of conditions causing perturbations to the commensal microbiota or host immunity. Early innate immune responses by the epithelium, including antimicrobial peptides (AMPs) and cytokines, are critical for protection against overgrowth. Reduced salivary AMP levels are associated with oral Candida infection and certain AMPs, including human beta-defensins 1 - 3, have direct fungicidal activity. Here we demonstrate that murine β-Defensin 1 (mBD1) is important for control of early mucosal Candida infection and plays a critical role in the induction of innate inflammatory mediators. Mice deficient in mBD1 exhibit elevated oral and systemic fungal burdens as compared to wild-type mice. Neutrophil infiltration to the sites of mucosal Candida invasion, an important step in limiting fungal infection, is significantly reduced in mBD1 deficient mice. These mice also exhibit defects in the expression of other antimicrobial peptides, including mBD2 and mBD4, which may have direct anti-Candida activity. We also show that mBD1 deficiency impacts the production of important anti-fungal inflammatory mediators including IL-1β, IL-6, KC, and IL-17. Collectively, these studies demonstrate a role for the mBD1 peptide in early control of Candida infection in a murine model of mucosal candidiasis, as well as on the modulation of host immunity through augmentation of leukocyte infiltration and inflammatory gene induction. PMID:25595775

  18. Mucosal immunisation with novel Streptococcus pneumoniae protein antigens enhances bacterial clearance in an acute mouse lung infection model.

    PubMed

    Jomaa, Maha; Kyd, Jennelle M; Cripps, Allan W

    2005-04-01

    Streptococcus pneumoniae contains many proteins that have not been evaluated as potential protective vaccine antigens. In this study we isolated proteins from a serotype 3 strain of S. pneumoniae for use in mouse immunisation studies. Separation of the protein mix was achieved by SDS-PAGE electrophoresis followed by electro-elution to isolate individual proteins. This procedure successfully separated 21 fractions from which six proteins were selected based on purity and quantity and were initially denoted by their molecular masses: 14-, 34-, 38-, 48-, 57- and 75-kDa. The immunogenicity of these proteins was investigated in a mucosal immunisation model in mice involving a primary inoculation to the intestinal Peyer's patches followed by an intra-tracheal boost two weeks later. The immune response was assessed by enhancement of pulmonary clearance of infection, recruitment of phagocytes to the lungs and induction of an antibody response. Two of the proteins, the 14-kDa identified as a L7/L12 ribosomal protein, and the 34-kDa identified as glyceraldehyde-3-phosphate dehydrogenase resulted in up to 99% and 94%, respectively, enhanced clearance of infection within 5 h following pulmonary challenge with S. pneumoniae. This study has shown that novel pneumococcal proteins have the potential to be vaccine candidates to enhance clearance of an acute mucosal S. pneumoniae infection. PMID:15780579

  19. The role of leukocytes in the pathogenesis of fibrin deposition in bovine acute lung injury.

    PubMed Central

    Car, B. D.; Suyemoto, M. M.; Neilsen, N. R.; Slauson, D. O.

    1991-01-01

    The peculiarly fibrinous nature of bovine acute lung injury due to infection with Pasteurella haemolytica A1 suggests an imbalance between leukocyte-directed procoagulant and profibrinolytic influences in the inflamed bovine lung. Calves with experimental pneumonia produced by intratracheal inoculation with P. haemolytica A1 developed acute locally extensive cranioventral fibrinopurulent bronchopneumonia. Pulmonary alveolar macrophages (PAM) recovered by segmental lavage from affected lung lobes were 30 times more procoagulant than PAM obtained from unaffected lung lobes and 37-fold more procoagulant than PAM from control calf lungs. Unlike the enhancement of procoagulant activity, profibrinolytic activity (plasminogen activator amidolysis) of total lung leukocytes (PAM and plasminogen activator neutrophils [PMN]) was decreased 23 times in cells obtained from affected lung lobes and also was decreased four times in cells obtained from unaffected lobes of infected animals. This marked imbalance in cellular procoagulant and fibrinolytic activity probably contributes significantly to enhanced fibrin deposition and retarded fibrin removal. In addition, PAM from inflamed lungs were strongly positive for bovine tissue factor antigen as demonstrated by immunocytochemistry. Intensely tissue factor-positive PAM enmeshed in fibrinocellular exudates and positive alveolar walls were situated such that they were likely to have, in concert, initiated extrinsic activation of coagulation in the acutely inflamed lung. These data collectively suggest that enhanced PAM-directed procoagulant activity and diminished PAM- and PMN-directed profibrinolytic activity represent important modifications of local leukocyte function in bovine acute lung injury that are central to the pathogenesis of lesion development with extensive fibrin deposition and retarded fibrin removal. Images Figure 2 Figure 3 PMID:2024707

  20. Acute Hendra virus infection: Analysis of the pathogenesis and passive antibody protection in the hamster model

    SciTech Connect

    Guillaume, Vanessa; Wong, K. Thong; Looi, R.Y.; Georges-Courbot, Marie-Claude; Barrot, Laura; Buckland, Robin; Wild, T. Fabian; Horvat, Branka

    2009-05-10

    Hendra virus (HeV) and Nipah virus (NiV) are recently-emerged, closely related and highly pathogenic paramyxoviruses. We have analysed here the pathogenesis of the acute HeV infection using the new animal model, golden hamster (Mesocricetus auratus), which is highly susceptible to HeV infection. HeV-specific RNA and viral antigens were found in multiple organs and virus was isolated from different tissues. Dual pathogenic mechanism was observed: parenchymal infection in various organs, including the brain, with vasculitis and multinucleated syncytia in many blood vessels. Furthermore, monoclonal antibodies specific for the NiV fusion protein neutralized HeV in vitro and efficiently protected hamsters from HeV if given before infection. These results reveal the similarities between HeV and NiV pathogenesis, particularly in affecting both respiratory and neuronal system. They demonstrate that hamster presents a convenient novel animal model to study HeV infection, opening new perspectives to evaluate vaccine and therapeutic approaches against this emergent infectious disease.

  1. Host immune response and acute disease in a zebrafish model of francisella pathogenesis

    USGS Publications Warehouse

    Vojtech, L.N.; Sanders, G.E.; Conway, C.; Ostland, V.; Hansen, J.D.

    2009-01-01

    Members of the bacterial genus Francisella are highly virulent and infectious pathogens. New models to study Francisella pathogenesis in evolutionarily distinct species are needed to provide comparative insight, as the mechanisms of host resistance and pathogen virulence are not well understood. We took advantage of the recent discovery of a novel species of Francisella to establish a zebrafish/Francisella comparative model of pathogenesis and host immune response. Adult zebraflsh were susceptible to acute Francisella-induced disease and suffered mortality in a dose-dependent manner. Using immunohistochemical analysis, we localized bacterial antigens primarily to lymphoid tissues and livers of zebraflsh following infection by intraperitoneal injection, which corresponded to regions of local cellular necrosis. Francisella sp. bacteria replicated rapidly in these tissues beginning 12 h postinfection, and bacterial titers rose steadily, leveled off, and then decreased by 7 days postinfection. Zebraflsh mounted a significant tissue-specific proinflammatory response to infection as measured by the upregulation of interleukin-l?? (IL-1??), gamma interferon, and tumor necrosis factor alpha mRNA beginning by 6 h postinfection and persisting for up to 7 days postinfection. In addition, exposure of zebraflsh to heat-killed bacteria demonstrated that the significant induction of IL-?? was highly specific to live bacteria. Taken together, the pathology and immune response to acute Francisella infection in zebraflsh share many features with those in mammals, highlighting the usefulness of this new model system for addressing both general and specific questions about Francisella host-pathogen interactions via an evolutionary approach. Copyright ?? 2009, American Society for Microbiology. All Rights Reserved.

  2. Acute-on-chronic liver failure: Pathogenesis, prognostic factors and management

    PubMed Central

    Blasco-Algora, Sara; Masegosa-Ataz, José; Gutiérrez-García, María Luisa; Alonso-López, Sonia; Fernández-Rodríguez, Conrado M

    2015-01-01

    Acute-on-chronic liver failure (ACLF) is increasingly recognized as a complex syndrome that is reversible in many cases. It is characterized by an acute deterioration of liver function in the background of a pre-existing chronic liver disease often associated with a high short-term mortality rate. Organ failure (OF) is always associated, and plays a key role in determining the course, and the outcome of the disease. The definition of ACLF remains controversial due to its overall ambiguity, with several disparate criteria among various associations dedicated to the study of liver diseases. Although the precise pathogenesis needs to be clarified, it appears that an altered host response to injury might be a contributing factor caused by immune dysfunction, ultimately leading to a pro-inflammatory status, and eventually to OF. The PIRO concept (Predisposition, Insult, Response and Organ Failure) has been proposed to better approach the underlying mechanisms. It is accepted that ACLF is a different and specific form of liver failure, where a precipitating event is always involved, even though it cannot always be ascertained. According to several studies, infections and active alcoholism often trigger ACLF. Viral hepatitis, gastrointestinal haemorrhage, or drug induced liver injury, which can also provoke the syndrome. This review mainly focuses on the physiopathology and prognostic aspects. We believe these features are essential to further understanding and providing the rationale for improveddisease management strategies. PMID:26576097

  3. Acute Generalized Exanthematous Pustulosis: Pathogenesis, Genetic Background, Clinical Variants and Therapy.

    PubMed

    Feldmeyer, Laurence; Heidemeyer, Kristine; Yawalkar, Nikhil

    2016-01-01

    Acute generalized exanthematous pustulosis (AGEP) is a severe, usually drug-related reaction, characterized by an acute onset of mainly small non-follicular pustules on an erythematous base and spontaneous resolution usually within two weeks. Systemic involvement occurs in about 20% of cases. The course is mostly benign, and only in rare cases complications lead to life-threatening situations. Recent studies highlight the importance of genetic variations in interleukin-36 receptor antagonist gene (IL-36RN) in the pathogenesis of this disease. The physiopathology of AGEP remains unclear, but an involvement of innate and acquired immune cells together with resident cells (keratinocytes), which recruit and activate neutrophils via production of cytokines/chemokines such as IL-17, IL-36, granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor alpha (TNFα) and chemokine (C-X-C motif) ligand 8 (CXCL8)/IL-8, has been postulated. Treatment is based on the removal of the causative drug, supportive care, infection prevention and use of potent topical or systemic steroids. PMID:27472323

  4. Acute Generalized Exanthematous Pustulosis: Pathogenesis, Genetic Background, Clinical Variants and Therapy

    PubMed Central

    Feldmeyer, Laurence; Heidemeyer, Kristine; Yawalkar, Nikhil

    2016-01-01

    Acute generalized exanthematous pustulosis (AGEP) is a severe, usually drug-related reaction, characterized by an acute onset of mainly small non-follicular pustules on an erythematous base and spontaneous resolution usually within two weeks. Systemic involvement occurs in about 20% of cases. The course is mostly benign, and only in rare cases complications lead to life-threatening situations. Recent studies highlight the importance of genetic variations in interleukin-36 receptor antagonist gene (IL-36RN) in the pathogenesis of this disease. The physiopathology of AGEP remains unclear, but an involvement of innate and acquired immune cells together with resident cells (keratinocytes), which recruit and activate neutrophils via production of cytokines/chemokines such as IL-17, IL-36, granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor alpha (TNFα) and chemokine (C-X-C motif) ligand 8 (CXCL8)/IL-8, has been postulated. Treatment is based on the removal of the causative drug, supportive care, infection prevention and use of potent topical or systemic steroids. PMID:27472323

  5. Efficacy and effects of palifermin for the treatment of oral mucositis in patients affected by acute lymphoblastic leukemia.

    PubMed

    Lucchese, Alessandra; Matarese, Giovanni; Ghislanzoni, Luis Huanca; Gastaldi, Giorgio; Manuelli, Maurizio; Gherlone, Enrico

    2016-01-01

    This randomized-controlled trial studied the efficacy of palifermin, administered as a dose during hematopoietic stem cell transplant (HSCT) therapy, as primary prophylaxis on pediatric patients with acute lymphoblastic leukemia in order to reduce oral mucositis (OM). Patients in the palifermin group were randomly assigned to receive palifermin, 60 μg/kg, intravenously as a single dose 3 days before and 0, +1, and +2 post autologous HSCT infusion. The patients in the control group received only a placebo treatment. OM-related assessments were the WHO oral-toxicity scale and the patient-reported outcomes. There was a statistically significant reduction in the incidence of OM grade 3 and 4 in the palifermin group compared to the control group. There was also a reduction in the degree of severity of OM in the palifermin group (1.65 grade respect to 2.33 in the control group). Palifermin could prevent the recurrence of severe OM and improve the quality of life in patients with acute lymphoblastic leukemia (ALL). PMID:26428409

  6. The Insect Peptide Coprisin Prevents Clostridium difficile-Mediated Acute Inflammation and Mucosal Damage through Selective Antimicrobial Activity▿

    PubMed Central

    Kang, Jin Ku; Hwang, Jae Sam; Nam, Hyo Jung; Ahn, Keun Jae; Seok, Heon; Kim, Sung-Kuk; Yun, Eun Young; Pothoulakis, Charalabos; Lamont, John Thomas; Kim, Ho

    2011-01-01

    Clostridium difficile-associated diarrhea and pseudomembranous colitis are typically treated with vancomycin or metronidazole, but recent increases in relapse incidence and the emergence of drug-resistant strains of C. difficile indicate the need for new antibiotics. We previously isolated coprisin, an antibacterial peptide from Copris tripartitus, a Korean dung beetle, and identified a nine-amino-acid peptide in the α-helical region of it (LLCIALRKK) that had antimicrobial activity (J.-S. Hwang et al., Int. J. Pept., 2009, doi:10.1155/2009/136284). Here, we examined whether treatment with a coprisin analogue (a disulfide dimer of the nine peptides) prevented inflammation and mucosal damage in a mouse model of acute gut inflammation established by administration of antibiotics followed by C. difficile infection. In this model, coprisin treatment significantly ameliorated body weight decreases, improved the survival rate, and decreased mucosal damage and proinflammatory cytokine production. In contrast, the coprisin analogue had no apparent antibiotic activity against commensal bacteria, including Lactobacillus and Bifidobacterium, which are known to inhibit the colonization of C. difficile. The exposure of C. difficile to the coprisin analogue caused a marked increase in nuclear propidium iodide (PI) staining, indicating membrane damage; the staining levels were similar to those seen with bacteria treated with a positive control for membrane disruption (EDTA). In contrast, coprisin analogue treatment did not trigger increases in the nuclear PI staining of Bifidobacterium thermophilum. This observation suggests that the antibiotic activity of the coprisin analogue may occur through specific membrane disruption of C. difficile. Thus, these results indicate that the coprisin analogue may prove useful as a therapeutic agent for C. difficile infection-associated inflammatory diarrhea and pseudomembranous colitis. PMID:21807975

  7. Probiotics Prevent Intestinal Barrier Dysfunction in Acute Pancreatitis in Rats via Induction of Ileal Mucosal Glutathione Biosynthesis

    PubMed Central

    Lutgendorff, Femke; Nijmeijer, Rian M.; Sandström, Per A.; Trulsson, Lena M.; Magnusson, Karl-Eric; Timmerman, Harro M.; van Minnen, L. Paul; Rijkers, Ger T.; Gooszen, Hein G.; Akkermans, Louis M. A.; Söderholm, Johan D.

    2009-01-01

    Background During acute pancreatitis (AP), oxidative stress contributes to intestinal barrier failure. We studied actions of multispecies probiotics on barrier dysfunction and oxidative stress in experimental AP. Methodology/Principal Findings Fifty-three male Spraque-Dawley rats were randomly allocated into five groups: 1) controls, non-operated, 2) sham-operated, 3) AP, 4) AP and probiotics and 5) AP and placebo. AP was induced by intraductal glycodeoxycholate infusion and intravenous cerulein (6 h). Daily probiotics or placebo were administered intragastrically, starting five days prior to AP. After cerulein infusion, ileal mucosa was collected for measurements of E. coli K12 and 51Cr-EDTA passage in Ussing chambers. Tight junction proteins were investigated by confocal immunofluorescence imaging. Ileal mucosal apoptosis, lipid peroxidation, and glutathione levels were determined and glutamate-cysteine-ligase activity and expression were quantified. AP-induced barrier dysfunction was characterized by epithelial cell apoptosis and alterations of tight junction proteins (i.e. disruption of occludin and claudin-1 and up-regulation of claudin-2) and correlated with lipid peroxidation (r>0.8). Probiotic pre-treatment diminished the AP-induced increase in E. coli passage (probiotics 57.4±33.5 vs. placebo 223.7±93.7 a.u.; P<0.001), 51Cr-EDTA flux (16.7±10.1 vs. 32.1±10.0 cm/s10−6; P<0.005), apoptosis, lipid peroxidation (0.42±0.13 vs. 1.62±0.53 pmol MDA/mg protein; P<0.001), and prevented tight junction protein disruption. AP-induced decline in glutathione was not only prevented (14.33±1.47 vs. 8.82±1.30 nmol/mg protein, P<0.001), but probiotics even increased mucosal glutathione compared with sham rats (14.33±1.47 vs. 10.70±1.74 nmol/mg protein, P<0.001). Glutamate-cysteine-ligase activity, which is rate-limiting in glutathione biosynthesis, was enhanced in probiotic pre-treated animals (probiotics 2.88±1.21 vs. placebo 1.94±0.55 nmol/min/mg protein; P<0

  8. Severe acute respiratory syndrome coronavirus envelope protein ion channel activity promotes virus fitness and pathogenesis.

    PubMed

    Nieto-Torres, Jose L; DeDiego, Marta L; Verdiá-Báguena, Carmina; Jimenez-Guardeño, Jose M; Regla-Nava, Jose A; Fernandez-Delgado, Raul; Castaño-Rodriguez, Carlos; Alcaraz, Antonio; Torres, Jaume; Aguilella, Vicente M; Enjuanes, Luis

    2014-05-01

    Deletion of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) envelope (E) gene attenuates the virus. E gene encodes a small multifunctional protein that possesses ion channel (IC) activity, an important function in virus-host interaction. To test the contribution of E protein IC activity in virus pathogenesis, two recombinant mouse-adapted SARS-CoVs, each containing one single amino acid mutation that suppressed ion conductivity, were engineered. After serial infections, mutant viruses, in general, incorporated compensatory mutations within E gene that rendered active ion channels. Furthermore, IC activity conferred better fitness in competition assays, suggesting that ion conductivity represents an advantage for the virus. Interestingly, mice infected with viruses displaying E protein IC activity, either with the wild-type E protein sequence or with the revertants that restored ion transport, rapidly lost weight and died. In contrast, mice infected with mutants lacking IC activity, which did not incorporate mutations within E gene during the experiment, recovered from disease and most survived. Knocking down E protein IC activity did not significantly affect virus growth in infected mice but decreased edema accumulation, the major determinant of acute respiratory distress syndrome (ARDS) leading to death. Reduced edema correlated with lung epithelia integrity and proper localization of Na+/K+ ATPase, which participates in edema resolution. Levels of inflammasome-activated IL-1β were reduced in the lung airways of the animals infected with viruses lacking E protein IC activity, indicating that E protein IC function is required for inflammasome activation. Reduction of IL-1β was accompanied by diminished amounts of TNF and IL-6 in the absence of E protein ion conductivity. All these key cytokines promote the progression of lung damage and ARDS pathology. In conclusion, E protein IC activity represents a new determinant for SARS-CoV virulence. PMID:24788150

  9. Severe Acute Respiratory Syndrome Coronavirus Envelope Protein Ion Channel Activity Promotes Virus Fitness and Pathogenesis

    PubMed Central

    Nieto-Torres, Jose L.; DeDiego, Marta L.; Verdiá-Báguena, Carmina; Jimenez-Guardeño, Jose M.; Regla-Nava, Jose A.; Fernandez-Delgado, Raul; Castaño-Rodriguez, Carlos; Alcaraz, Antonio; Torres, Jaume; Aguilella, Vicente M.; Enjuanes, Luis

    2014-01-01

    Deletion of Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) envelope (E) gene attenuates the virus. E gene encodes a small multifunctional protein that possesses ion channel (IC) activity, an important function in virus-host interaction. To test the contribution of E protein IC activity in virus pathogenesis, two recombinant mouse-adapted SARS-CoVs, each containing one single amino acid mutation that suppressed ion conductivity, were engineered. After serial infections, mutant viruses, in general, incorporated compensatory mutations within E gene that rendered active ion channels. Furthermore, IC activity conferred better fitness in competition assays, suggesting that ion conductivity represents an advantage for the virus. Interestingly, mice infected with viruses displaying E protein IC activity, either with the wild-type E protein sequence or with the revertants that restored ion transport, rapidly lost weight and died. In contrast, mice infected with mutants lacking IC activity, which did not incorporate mutations within E gene during the experiment, recovered from disease and most survived. Knocking down E protein IC activity did not significantly affect virus growth in infected mice but decreased edema accumulation, the major determinant of acute respiratory distress syndrome (ARDS) leading to death. Reduced edema correlated with lung epithelia integrity and proper localization of Na+/K+ ATPase, which participates in edema resolution. Levels of inflammasome-activated IL-1β were reduced in the lung airways of the animals infected with viruses lacking E protein IC activity, indicating that E protein IC function is required for inflammasome activation. Reduction of IL-1β was accompanied by diminished amounts of TNF and IL-6 in the absence of E protein ion conductivity. All these key cytokines promote the progression of lung damage and ARDS pathology. In conclusion, E protein IC activity represents a new determinant for SARS-CoV virulence. PMID:24788150

  10. Beneficial effects of Foeniculum vulgare on ethanol-induced acute gastric mucosal injury in rats

    PubMed Central

    Birdane, Fatih Mehmet; Cemek, Mustafa; Birdane, Yavuz Osman; Gülçin, İlhami; Büyükokuroğlu, Mehmet Emin

    2007-01-01

    AIM: To examine the anti-ulcerogenic and antioxidant effects of aqueous extracts of Foeniculum vulgare (FVE) on ethanol-induced gastric lesions in rats. METHODS: FVE was administered by gavage at doses of 75, 150 and 300 mg/kg, and famotidine was used at the dose of 20 mg/kg. Following a 60 min period, all the rats were given 1 mL of ethanol (80%) by gavage. One hour after the administration of ethanol, all groups were sacrificed, and the gastric ulcer index was calculated; whole blood malondialdehyde (MDA) and reduced glutathione (GSH), serum nitrate, nitrite, ascorbic acid, retinol and β-carotene levels were measured in all the groups. RESULTS: It was found that pretreatment with FVE significantly reduced ethanol-induced gastric damage. This effect of FVE was highest and statistically significant in 300 mg/kg group compared with the control (4.18 ± 2.81 vs 13.15 ± 4.08, P < 0.001). Also, pretreatment with FVE significantly reduced the MDA levels, while significantly increased GSH, nitrite, nitrate, ascorbic acid, retinol and β-carotene levels. CONCLUSION: FVE has clearly a protective effect against ethanol-induced gastric mucosal lesion, and this effect, at least in part, depends upon the reduction in lipid peroxidation and augmentation in the antioxidant activity. PMID:17278229

  11. Acute hematologic and mucosal toxicities in head and neck cancer patients undergoing chemoradiotherapy: a comparison of 3D-CRT, IMRT, and helical tomotherapy.

    PubMed

    Kruser, Tim J; Rice, Stephanie R; Cleary, Kevin P; Geye, Heather M; Tome, Wolfgang A; Harari, Paul M; Kozak, Kevin R

    2013-10-01

    IMRT and helical tomotherapy for head and neck cancer (HNC) treatment are associated with higher doses to certain non-target tissues than traditional static beam techniques. We hypothesized that this may lead to higher acute mucosal and hematologic toxicities. This analysis was limited to 178 patients receiving ≥60 Gy with concurrent weekly cisplatin. Radiation delivery used 3D-CRT in 41 patients (23%), conventional IMRT in 56 patients (31%), and helical tomotherapy in 81 patients (46%). Acute mucositis rates, weekly hematologic parameters, and ability to deliver planned chemotherapy cycles were examined for each patient during their course of chemoradiotherapy. Analysis showed patients were well balanced with regard to sex, age, and stage. Treatment time, as assessed by delivered monitor units, varied significantly between the 3D-CRT (median = 502), IMRT (median = 1087), and tomotherapy (median = 6757) cohorts. Acute mucositis grades did not significantly differ between the three subsets. Through six weeks of chemoradiotherapy, the median decline in hemoglobin was 15.6%, the median decline in platelets was 30.6%, and the median decline in leukocytes was 51.5%, but these drops were not significantly different between treatment cohorts. Chemotherapy was discontinued or held secondary to hematologic toxicity in 12% of 3D-CRT patients, 5% of IMRT patients and 15% of tomotherapy patients (p = 0.14). In conclusion, HNC patients undergoing high dose radiation with concurrent weekly cisplatin chemotherapy, the longer beam-on times and larger volumes of low-to-moderate radiation doses to non-target tissues associated with modern IMRT delivery techniques do not appear to result in increased acute hematologic or mucosal toxicities. PMID:23547974

  12. Gastric mucosal cell proliferation in ethanol-induced chronic mucosal injury is related to oxidative stress and lipid peroxidation in rats.

    PubMed

    Hernández-Muñoz, R; Montiel-Ruíz, C; Vázquez-Martínez, O

    2000-08-01

    The oxygen free radicals-induced lipid peroxidation (LP) has been implicated in the pathogenesis of acute ethanol-induced gastric mucosal lesions. However, the role of LP in the generation of chronic gastric mucosal injury is unknown. We have developed a model of chronic mucosal injury induced by continuous ethanol ingestion for 5 days and characterized by marked alterations in plasma membranes from gastric mucosa. Therefore, LP was evaluated in this experimental model. Indicators of peroxidative activity, mucosal glutathione content, thymidine kinase activity (an index of cell proliferation), and histamine H2-receptor (H2R) binding constants were quantified in animals undergoing gastric mucosal damage. The effect of famotidine, a H2R antagonist that readily ameliorates the chronic mucosal injury, was also tested. Increased free radicals and LP levels were detected during gastritis; however, a second, higher peak of LP was noted in mucosal plasma membranes after ethanol withdrawal (recovery period). This further increase of LP coincided with active cell proliferation, decreased mucosal glutathione levels, and diminished specific cimetidine binding by H2R. Administration of famotidine accelerated the mucosal proliferative process, inducing the second lipoperoxidative episode sooner, and preserved the content of glutathione. In addition, LP correlated directly with cell proliferation and inversely with mucosal membrane cimetidine binding. In conclusion, LP seems to be involved in chronic ethanol-induced gastric mucosal injury. However, a further enhancement of plasma membrane LP occurred, associated with increased DNA synthesis and diminished cimetidine binding by membrane H2R. Therefore, increased LP could also participate in the compensatory mucosal proliferation initiated after ethanol withdrawal. PMID:10950107

  13. MicroRNA signature of intestinal acute cellular rejection in formalin-fixed paraffin-embedded mucosal biopsies.

    PubMed

    Asaoka, T; Sotolongo, B; Island, E R; Tryphonopoulos, P; Selvaggi, G; Moon, J; Tekin, A; Amador, A; Levi, D M; Garcia, J; Smith, L; Nishida, S; Weppler, D; Tzakis, A G; Ruiz, P

    2012-02-01

    Despite continuous improvement of immunosuppression, small bowel transplantation (SBT) is plagued by a high incidence of acute cellular rejection (ACR) that is frequently intractable. Therefore, there is a need to uncover novel insights that will lead to strategies to achieve better control of ACR. We hypothesized that particular miRNAs provide critical regulation of the intragraft immune response. The aim of our study was to identify miRNAs involved in intestinal ACR. We examined 26 small intestinal mucosal biopsies (AR/NR group; 15/11) obtained from recipients after SBT or multivisceral transplantation. We investigated the expression of 384 mature human miRNAs and 280 mRNAs associated with immune, inflammation and apoptosis processes. We identified differentially expressed 28 miRNAs and 58 mRNAs that characterized intestinal ACR. We found a strong positive correlation between the intragraft expression levels of three miRNAs (miR-142-3p, miR-886-3p and miR-132) and 17 mRNAs including CTLA4 and GZMB. We visualized these miRNAs within cells expressing CD3 and CD14 proteins in explanted intestinal allografts with severe ACR. Our data suggested that miRNAs have a critical role in the activation of infiltrating cells during intestinal ACR. These differences in miRNA expression patterns can be used to identify novel biomarkers and therapeutic targets for immunosuppressive agents. PMID:22026534

  14. A New Model for Predicting Acute Mucosal Toxicity in Head-and-Neck Cancer Patients Undergoing Radiotherapy With Altered Schedules

    SciTech Connect

    Strigari, Lidia; Pedicini, Piernicola; D'Andrea, Marco; Pinnaro, Paola; Marucci, Laura; Giordano, Carolina; Benassi, Marcello

    2012-08-01

    Purpose: One of the worst radiation-induced acute effects in treating head-and-neck (HN) cancer is grade 3 or higher acute (oral and pharyngeal) mucosal toxicity (AMT), caused by the killing/depletion of mucosa cells. Here we aim to testing a predictive model of the AMT in HN cancer patients receiving different radiotherapy schedules. Methods and Materials: Various radiotherapeutic schedules have been reviewed and classified as tolerable or intolerable based on AMT severity. A modified normal tissue complication probability (NTCP) model has been investigated to describe AMT data in radiotherapy regimens, both conventional and altered in dose and overall treatment time (OTT). We tested the hypothesis that such a model could also be applied to identify intolerable treatment and to predict AMT. This AMT NTCP model has been compared with other published predictive models to identify schedules that are either tolerable or intolerable. The area under the curve (AUC) was calculated for all models, assuming treatment tolerance as the gold standard. The correlation between AMT and the predicted toxicity rate was assessed by a Pearson correlation test. Results: The AMT NTCP model was able to distinguish between acceptable and intolerable schedules among the data available for the study (AUC = 0.84, 95% confidence interval = 0.75-0.92). In the equivalent dose at 2 Gy/fraction (EQD2) vs OTT space, the proposed model shows a trend similar to that of models proposed by other authors, but was superior in detecting some intolerable schedules. Moreover, it was able to predict the incidence of {>=}G3 AMT. Conclusion: The proposed model is able to predict {>=}G3 AMT after HN cancer radiotherapy, and could be useful for designing altered/hypofractionated schedules to reduce the incidence of AMT.

  15. Comparative genomics reveals multistep pathogenesis of E2A-PBX1 acute lymphoblastic leukemia

    PubMed Central

    Duque-Afonso, Jesús; Feng, Jue; Scherer, Florian; Lin, Chiou-Hong; Wong, Stephen H.K.; Wang, Zhong; Iwasaki, Masayuki; Cleary, Michael L.

    2015-01-01

    Acute lymphoblastic leukemia (ALL) is the most common childhood cancer; however, its genetic diversity limits investigation into the molecular pathogenesis of disease and development of therapeutic strategies. Here, we engineered mice that conditionally express the E2A-PBX1 fusion oncogene, which results from chromosomal translocation t(1;19) and is present in 5% to 7% of pediatric ALL cases. The incidence of leukemia in these mice varied from 5% to 50%, dependent on the Cre-driving promoter (Cd19, Mb1, or Mx1) used to induce E2A-PBX1 expression. Two distinct but highly similar subtypes of B cell precursor ALLs that differed by their pre–B cell receptor (pre-BCR) status were induced and displayed maturation arrest at the pro-B/large pre–B II stages of differentiation, similar to human E2A-PBX1 ALL. Somatic activation of E2A-PBX1 in B cell progenitors enhanced self-renewal and led to acquisition of multiple secondary genomic aberrations, including prominent spontaneous loss of Pax5. In preleukemic mice, conditional Pax5 deletion cooperated with E2A-PBX1 to expand progenitor B cell subpopulations, increasing penetrance and shortening leukemia latency. Recurrent secondary activating mutations were detected in key signaling pathways, most notably JAK/STAT, that leukemia cells require for proliferation. These data support conditional E2A-PBX1 mice as a model of human ALL and suggest targeting pre-BCR signaling and JAK kinases as potential therapeutic strategies. PMID:26301816

  16. Mucosal and Parenteral Vaccination against Acute and Latent Murine Cytomegalovirus (MCMV) Infection by Using an Attenuated MCMV Mutant

    PubMed Central

    MacDonald, Margaret R.; Li, Xi-Yang; Stenberg, Richard M.; Campbell, Ann E.; Virgin, Herbert W.

    1998-01-01

    We used a live attenuated murine cytomegalovirus (MCMV) mutant to analyze mechanisms of vaccination against acute and latent CMV infection. We selected MCMV mutant RV7 as a vaccine candidate since this virus grows well in tissue culture but is profoundly attenuated for growth in normal and severe combined immunodeficient (SCID) mice (V. J. Cavanaugh et al., J. Virol. 70:1365–1374, 1996). BALB/c mice were immunized twice (0 and 14 days) subcutaneously (s.c.) with tissue culture-passaged RV7 and then challenged with salivary gland-passaged wild-type MCMV (sgMCMV) intraperitoneally (i.p.) on day 28. RV7 vaccination protected mice against challenge with 105 PFU of sgMCMV, a dose that killed 100% of mock-vaccinated mice. RV7 vaccination reduced MCMV replication 100- to 500-fold in the spleen between 1 and 8 days after challenge. We used the capacity to control replication of MCMV in the spleen 4 days after challenge as a surrogate for protection. Protection was antigen specific and required both live RV7 and antigen-specific lymphocytes. Interestingly, RV7 was effective when administered s.c., i.p., perorally, intranasally, and intragastrically, demonstrating that attenuated CMV applied to mucosal surfaces can elicit protection against parenteral virus challenge. B cells and immunoglobulin G were not essential for RV7-induced immunity since B-cell-deficient mice were effectively vaccinated by RV7. CD8 T cells, but not CD4 T cells, were critical for RV7-induced protection. Depletion of CD8 T cells by passive transfer of monoclonal anti-CD8 (but not anti-CD4) antibody abrogated RV7-mediated protection, and RV7 vaccination was less efficient in CD8 T-cell-deficient mice with a targeted mutation in the β2-microglobulin gene. Although gamma interferon is important for innate resistance to MCMV, it was not essential for RV7 vaccination since gamma interferon receptor-deficient mice were protected by RV7 vaccination. Establishment of and/or reactivation from latency by sg

  17. Acute bovine viral diarrhea associated with extensive mucosal lesions, high morbidity, and mortality in a commercial feedlot

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In 2008, a northwest Texas feedlot underwent an outbreak of bovine viral diarrhea virus (BVDV) disease causing high morbidity and mortality involving two lots of calves (Lots A and B). Severe mucosal surface lesions were observed grossly in the oral cavity, larynx and esophagus. Mucosal lesions vari...

  18. Dietary flaxseed intake exacerbates acute colonic mucosal injury and inflammation induced by dextran sodium sulfate.

    PubMed

    Zarepoor, Leila; Lu, Jenifer T; Zhang, Claire; Wu, Wenqing; Lepp, Dion; Robinson, Lindsay; Wanasundara, Janitha; Cui, Steve; Villeneuve, Sébastien; Fofana, Bourlaye; Tsao, Rong; Wood, Geoffrey A; Power, Krista A

    2014-06-15

    Flaxseed (FS), a dietary oilseed, contains a variety of anti-inflammatory bioactives, including fermentable fiber, phenolic compounds (lignans), and the n-3 polyunsaturated fatty acid (PUFA) α-linolenic acid. The objective of this study was to determine the effects of FS and its n-3 PUFA-rich kernel or lignan- and soluble fiber-rich hull on colitis severity in a mouse model of acute colonic inflammation. C57BL/6 male mice were fed a basal diet (negative control) or a basal diet supplemented with 10% FS, 6% kernel, or 4% hull for 3 wk prior to and during colitis induction via 5 days of 2% (wt/vol) dextran sodium sulfate (DSS) in their drinking water (n = 12/group). An increase in anti-inflammatory metabolites (hepatic n-3 PUFAs, serum mammalian lignans, and cecal short-chain fatty acids) was associated with consumption of all FS-based diets, but not with anti-inflammatory effects in DSS-exposed mice. Dietary FS exacerbated DSS-induced acute colitis, as indicated by a heightened disease activity index and an increase in colonic injury and inflammatory biomarkers [histological damage, apoptosis, myeloperoxidase, inflammatory cytokines (IL-6 and IL-1β), and NF-κB signaling-related genes (Nfkb1, Ccl5, Bcl2a1a, Egfr, Relb, Birc3, and Atf1)]. Additionally, the adverse effect of the FS diet was extended systemically, as serum cytokines (IL-6, IFNγ, and IL-1β) and hepatic cholesterol levels were increased. The adverse effects of FS were not associated with alterations in fecal microbial load or systemic bacterial translocation (endotoxemia). Collectively, this study demonstrates that although consumption of a 10% FS diet enhanced the levels of n-3 PUFAs, short-chain polyunsaturated fatty acids, and lignans in mice, it exacerbated DSS-induced colonic injury and inflammation. PMID:24763556

  19. Mucosal Immunization with Surface-Displayed Severe Acute Respiratory Syndrome Coronavirus Spike Protein on Lactobacillus casei Induces Neutralizing Antibodies in Mice

    PubMed Central

    Lee, Jong-Soo; Poo, Haryoung; Han, Dong P.; Hong, Seung-Pyo; Kim, Kwang; Cho, Michael W.; Kim, Eun; Sung, Moon-Hee; Kim, Chul-Joong

    2006-01-01

    Induction of mucosal immunity may be important for preventing SARS-CoV infections. For safe and effective delivery of viral antigens to the mucosal immune system, we have developed a novel surface antigen display system for lactic acid bacteria using the poly-γ-glutamic acid synthetase A protein (PgsA) of Bacillus subtilis as an anchoring matrix. Recombinant fusion proteins comprised of PgsA and the Spike (S) protein segments SA (residues 2 to 114) and SB (residues 264 to 596) were stably expressed in Lactobacillus casei. Surface localization of the fusion protein was verified by cellular fractionation analyses, immunofluorescence microscopy, and flow cytometry. Oral and nasal inoculations of recombinant L. casei into mice resulted in high levels of serum immunoglobulin G (IgG) and mucosal IgA, as demonstrated by enzyme-linked immunosorbent assays using S protein peptides. More importantly, these antibodies exhibited potent neutralizing activities against severe acute respiratory syndrome (SARS) pseudoviruses. Orally immunized mice mounted a greater neutralizing-antibody response than those immunized intranasally. Three new neutralizing epitopes were identified on the S protein using a peptide neutralization interference assay (residues 291 to 308, 520 to 529, and 564 to 581). These results indicate that mucosal immunization with recombinant L. casei expressing SARS-associated coronavirus S protein on its surface provides an effective means for eliciting protective immune response against the virus. PMID:16571824

  20. Defining and Regulating Acute Inflammatory Lesion Formation during the Pathogenesis of Multiple Sclerosis and Experimental Autoimmune Encephalomyelitis.

    PubMed

    Bolton, Christopher; Smith, Paul

    2015-01-01

    The primary pathology of the human central nervous system disease multiple sclerosis (MS) and the animal counterpart experimental autoimmune encephalomyelitis (EAE) includes immunological and inflammatory events. Immune system involvement in MS has been widely debated but the role of inflammation has received less attention. Classic acute inflammation features vasculitis, resident tissue macrophage and mast cell participation plus the involvement of circulatory-derived neutrophils and platelets. Pre-lesion development in MS incorporates cerebral vasculitis, activated resident microglia in normal appearing white matter together with infiltrating cell types and factors indicative of an acute inflammatory reaction. Similarly, the formation of perivascular lesions during early EAE includes characteristic neurovasculitis, the participation of central nervous system microglial phenotypes plus haemopoietic cells and mediators, signifying an ongoing acute inflammatory response. EAE has been extensively used as a screen to select drugs for MS treatment but has been criticised as unrepresentative of the human condition due to fundamental differences in disease induction and pathogenesis. The review provides compelling evidence for a distinct acute inflammatory phase in MS lesion formation that is convincingly reproduced in early EAE pathology. Moreover, consideration of drug efficacy studies undertaken during initial EAE validates the occurrence of an acute inflammatory phase in disease pathogenesis. Critical appraisal, recognition and acceptance of the mutual acute inflammatory components inherent in the primary pathology of MS and EAE reveals new targets and encourages confident and reliable employment of the animal model in the assessment of novel compounds for the control of key primary pathological events in human demyelinating disease. PMID:26177741

  1. Effect of acid secretion blockade on acute gastric mucosal lesions induced by Tityus serrulatus scorpion toxin in anaesthetized rats.

    PubMed

    Melo, Júnio Rios; de Araújo, Gnana Keith Marques; da Luz, Magda Maria Profeta; da Conceição, Sérgio Alexandre; Lisboa, Felipe Assis; Moraes-Santos, Tasso; Cunha-Melo, José Renan

    2006-10-01

    Scorpion venom (TX) promotes gastric acid and pepsin secretion leading to acute gastric mucosal lesions (AGML), when injected in animals. The goal of the present study was to observe the effects of acid gastric secretion blockers over the incidence of TX-induced AGML in vivo. To verify this model, we used male albino rats, fasted 18-20 h (n=122) and anaesthetized with urethane (1.4 g/kg, i.p.). Their trachea and left femoral vein were both cannulated; the first to avoid airway obstructions during scorpion intoxication and the second for administration of saline, TX and acid blockers. Following the surgical procedure, the animals were divided in 10 groups of at least 10 animals each. Control groups were injected with NaCl 0.9% 1 ml/kg (n=10) or TX 375 microg/kg (n=32). Test groups (n=10, each) received atropine 5 mg/kg, cimetidine 10mg/kg, ranitidine 2.5mg/kg, ranitidine 5mg/kg, omeprazol 1 mg/kg, omeprazol 4 mg/kg, octreotide 80 and octreotide 100 microg/kg 10 min before the TX was injected. After 1h of intoxication, the stomach was resected for macroscopic study and the gastric secretion was collected for volume, pH and acid output assessment. We observed that all blockers were able to completely or partially prevent the TX-induced acid secretion as well as the AGML (p<0.05). Our data suggest the TX-induced AGML can be prevented by different class of acid blockers injected before the intoxication. PMID:16926041

  2. Mucosal vaccines

    PubMed Central

    Nizard, Mevyn; Diniz, Mariana O; Roussel, Helene; Tran, Thi; Ferreira, Luis CS; Badoual, Cecile; Tartour, Eric

    2014-01-01

    The mucosal immune system displays several adaptations reflecting the exposure to the external environment. The efficient induction of mucosal immune responses also requires specific approaches, such as the use of appropriate administration routes and specific adjuvants and/or delivery systems. In contrast to vaccines delivered via parenteral routes, experimental, and clinical evidences demonstrated that mucosal vaccines can efficiently induce local immune responses to pathogens or tumors located at mucosal sites as well as systemic response. At least in part, such features can be explained by the compartmentalization of mucosal B and T cell populations that play important roles in the modulation of local immune responses. In the present review, we discuss molecular and cellular features of the mucosal immune system as well as novel immunization approaches that may lead to the development of innovative and efficient vaccines targeting pathogens and tumors at different mucosal sites. PMID:25424921

  3. Effects of near-infrared laser radiation on the survival and inflammatory potential of Candida spp. involved in the pathogenesis of chemotherapy-induced oral mucositis.

    PubMed

    Clemente, A M; Rizzetto, L; Castronovo, G; Perissi, E; Tanturli, M; Cozzolino, F; Cavalieri, D; Fusi, F; Cialdai, F; Vignali, L; Torcia, M G; Monici, M

    2015-10-01

    Candida spp. usually colonize ulcerative lesions of atrophic mucosa in patients with chemotherapy-induced oral mucositis inducing severe inflammation. The spread of antifungal-resistant strains strongly encouraged the search of complementary or alternative therapeutic strategies to cure inflamed mucosa. In this paper, we studied the effects of a near-infrared (NIR) laser system with dual-wavelength emission (808 nm + 904 nm) on the survival and inflammatory potential of C. albicans, C. glabrata, and C. parapsilosis. Laser treatment was performed with a Multiwave Locked System laser. Survival and apoptosis of fungal strains were evaluated by colony-forming units (CFU) counting and annexin V staining. Cytokine production was evaluated by ImmunoPlex array. Laser treatment significantly affected the survival of Candida spp. by inducing apoptosis and induced a lower production of inflammatory cytokines by dendritic cells compared to untreated fungi. No differences in the survival and inflammatory potential were recorded in treated or untreated Saccharomyces cerevisiae cells, used as the control non-pathogenic microorganism. Laser treatment altered the survival and inflammatory potential of pathogenic Candida spp. These data provide experimental support to the use of NIR laser radiation as a co-adjuvant of antifungal therapy in patients with oral mucositis (OM) complicated by Candida infections. PMID:26173694

  4. LeuX tRNA-dependent and -independent mechanisms of Escherichia coli pathogenesis in acute cystitis

    PubMed Central

    Hannan, Thomas J.; Mysorekar, Indira U.; Chen, Swaine L.; Walker, Jennifer N.; Jones, Jennifer M.; Pinkner, Jerome S.; Hultgren, Scott J.; Seed, Patrick C.

    2013-01-01

    Summary Uropathogenic Escherichia coli (UPEC) contain multiple horizontally acquired pathogenicity-associated islands (PAI) implicated in the pathogenesis of urinary tract infection. In a murine model of cystitis, type 1 pili-mediated bladder epithelial invasion and intracellular proliferation are key events associated with UPEC virulence. In this study, we examined the mechanisms by which a conserved PAI contributes to UPEC pathogenesis in acute cystitis. In the human UPEC strain UTI89, spontaneous excision of PAI IIUTI89 disrupts the adjacent leuX tRNA locus. Loss of wild-type leuX-encoded tRNA5Leu significantly delayed, but did not eliminate, FimB recombinase-mediated phase variation of type 1 pili. FimX, an additional FimB-like, leuX-independent recombinase, was also found to mediate type 1 pili phase variation. However, whereas FimX activity is relatively slow in vitro, it is rapid in vivo as a non-piliated strain lacking the other fim recombinases rapidly expressed type 1 pili upon experimental infection. Finally, we found that disruption of leuX, but not loss of PAI IIUTI89 genes, reduced bladder epithelial invasion and intracellular proliferation, independent of type 1 piliation. These findings indicate that the predominant mechanism for preservation of PAI IIUTI89 during the establishment of acute cystitis is maintenance of wild-type leuX, and not PAI IIUTI89 gene content. PMID:18036139

  5. A C-type lectin receptor pathway is responsible for the pathogenesis of acute cyclophosphamide-induced cystitis in mice.

    PubMed

    Dejima, Takashi; Shibata, Kensuke; Yamada, Hisakata; Takeuchi, Ario; Hara, Hiromitsu; Eto, Masatoshi; Naito, Seiji; Yoshikai, Yasunobu

    2013-12-01

    Hemorrhagic cystitis often arises after cyclophosphamide (CYP) administration. As yet, however, the mechanism involved in its pathogenesis is unknown. In this study, it was found that the Fc receptor γ chain (FcRγ)- caspase recruitment domain-containing protein 9 (CARD9)-dependent pathway rather than the myeloid differentiation primary response gene 88 (MyD88)-dependent pathway is involved in the pathogenesis of acute CYP-induced cystitis in mice. Rapid and transient production of interleukin (IL)-6 and IL-1β was detected in the bladder at 4 hr, preceding IL-23 and IL-17A production and an influx of neutrophils, which reached a peak at 24 hr after injection. As assessed by weight, edema and neutrophil infiltration, cystitis was significantly attenuated in CARD9 knockout (KO) and FcRγKO mice, this attenuation being accompanied by impaired production of IL-1β, IL-6, IL-23 and IL-17A. The major source of IL-17A is the vesical γδ T cell population: IL-17AKO, CδKO and Tyk2KO mice showed little IL-17A production and reduced neutrophil infiltration in the bladder after CYP injection. These results suggest that FcRγ-CARD9-dependent production of proinflammatory cytokines such as IL-1β, IL-6, and IL-23 and the subsequent activation of IL-17A-producing γδ T cells are at least partly involved in the pathogenesis of acute CYP-induced cystitis in mice. PMID:24102807

  6. Wilms tumor 1 mutations in the pathogenesis of acute myeloid leukemia

    PubMed Central

    Rampal, Raajit; Figueroa, Maria E.

    2016-01-01

    Wilms tumor 1 (WT1) has long been implicated in acute myeloid leukemia. It has been described to be both overexpressed and mutated in different forms of acute myeloid leukemia, and overexpression has been reported to play a prognostic role in this disease. However, the precise mechanism through which WT1 may play a role in leukemogenesis has remained elusive. In recent years, new evidence has emerged that points towards a novel role of WT1 mutations in the deregulation of epigenetic programs in leukemic cells through its interaction with TET proteins. Herein we review the current status of the field and its therapeutic and prognostic implications in acute myeloid leukemia. PMID:27252512

  7. Acute Toxicity and Gastroprotective Role of M. pruriens in Ethanol-Induced Gastric Mucosal Injuries in Rats

    PubMed Central

    Hassandarvish, Pouya; Abdul Majid, Nazia; Hadi, A. Hamid A.; Nordin, Noraziah; Abdulla, Mahmood A.

    2013-01-01

    The investigation was to evaluate gastroprotective effects of ethanolic extract of M. pruriens leaves on ethanol-induced gastric mucosal injuries in rats. Forty-eight rats were divided into 8 groups: negative control, extract control, ulcer control, reference control, and four experimental groups. As a pretreatment, the negative control and the ulcer control groups were orally administered carboxymethylcellulose (CMC). The reference control was administered omeprazole orally (20 mg/kg). The ethanolic extract of M. pruriens leaves was given orally to the extract control group (500 mg/kg) and the experimental groups (62.5, 125, 250, and 500 mg/kg). After 1 h, CMC was given orally to the negative and the extract control groups. The other groups received absolute ethanol. The rats were sacrificed after 1 h. The ulcer control group exhibited significant mucosal injuries with decreased gastric wall mucus and severe damage to the gastric mucosa. The extract caused upregulation of Hsp70 protein, downregulation of Bax protein, and intense periodic acid schiff uptake of glandular portion of stomach. Gastric mucosal homogenate showed significant antioxidant properties with increase in synthesis of PGE2, while MDA was significantly decreased. The ethanolic extract of M. pruriens leaves was nontoxic (<5 g/kg) and could enhance defensive mechanisms against hemorrhagic mucosal lesions. PMID:23781513

  8. Acute toxicity and gastroprotective role of M. pruriens in ethanol-induced gastric mucosal injuries in rats.

    PubMed

    Golbabapour, Shahram; Hajrezaie, Maryam; Hassandarvish, Pouya; Abdul Majid, Nazia; Hadi, A Hamid A; Nordin, Noraziah; Abdulla, Mahmood A

    2013-01-01

    The investigation was to evaluate gastroprotective effects of ethanolic extract of M. pruriens leaves on ethanol-induced gastric mucosal injuries in rats. Forty-eight rats were divided into 8 groups: negative control, extract control, ulcer control, reference control, and four experimental groups. As a pretreatment, the negative control and the ulcer control groups were orally administered carboxymethylcellulose (CMC). The reference control was administered omeprazole orally (20 mg/kg). The ethanolic extract of M. pruriens leaves was given orally to the extract control group (500 mg/kg) and the experimental groups (62.5, 125, 250, and 500 mg/kg). After 1 h, CMC was given orally to the negative and the extract control groups. The other groups received absolute ethanol. The rats were sacrificed after 1 h. The ulcer control group exhibited significant mucosal injuries with decreased gastric wall mucus and severe damage to the gastric mucosa. The extract caused upregulation of Hsp70 protein, downregulation of Bax protein, and intense periodic acid schiff uptake of glandular portion of stomach. Gastric mucosal homogenate showed significant antioxidant properties with increase in synthesis of PGE2, while MDA was significantly decreased. The ethanolic extract of M. pruriens leaves was nontoxic (<5 g/kg) and could enhance defensive mechanisms against hemorrhagic mucosal lesions. PMID:23781513

  9. Spatiotemporal Interplay of Severe Acute Respiratory Syndrome Coronavirus and Respiratory Mucosal Cells Drives Viral Dissemination in Rhesus Macaques

    PubMed Central

    Liu, Li; Wei, Qiang; Nishiura, Kenji; Peng, Jie; Wang, Haibo; Midkiff, Cecily; Alvarez, Xavier; Qin, Chuan; Lackner, Andrew; Chen, Zhiwei

    2015-01-01

    Innate immune responses play a critical role in the control of early virus replication and dissemination. It remains unknown, however, how SARS-CoV evades respiratory innate immunity to establish a systemic infection. Here, we show in Chinese macaques that SARS-CoV traversed the mucosa through the respiratory tract within 2 days, resulting in extensive mucosal infiltration by T cells, MAC387+ and CD163+ monocytes/macrophages followed by limited viral replication in the lung but persistent viral shedding into the upper airway. Mucosal monocytes/macrophages sequestered virions in intracellular vesicles together with infected Langerhans cells (LCs) and migrated into the tonsils and/or draining lymph nodes (LNs) within 2 days. In lymphoid tissues, viral RNA and proteins were detected in infected monocytes upon differentiation into dendritic cells (DCs) within 3 days. Systemic viral dissemination was observed within 7 days. This study provides a comprehensive overview of the spatiotemporal interactions of SARS-CoV, monocytes/macrophages and the dendritic cell network in mucosal tissues and highlights the fact that while these innate cells contribute to viral clearance, they probably also serve as shelters and vehicles to provide a mechanism for the virus to escape host mucosal innate immunity and disseminate systemically. PMID:26647718

  10. The NOTCH signaling pathway: role in the pathogenesis of T-cell acute lymphoblastic leukemia and implication for therapy

    PubMed Central

    Tosello, Valeria

    2013-01-01

    T-cell acute lymphoblastic leukemia/lymphoma (T-ALL) is characterized by aberrant activation of NOTCH1 in over 60% of T-ALL cases. The high prevalence of activating NOTCH1 mutations highlights the critical role of NOTCH signaling in the pathogenesis of this disease and has prompted the development of therapeutic approaches targeting the NOTCH signaling pathway. Small molecule gamma secretase inhibitors (GSIs) can effectively inhibit oncogenic NOTCH1 and are in clinical testing for the treatment of T-ALL. Treatment with GSIs and glucocorticoids are strongly synergistic and may overcome the gastrointestinal toxicity associated with systemic inhibition of the NOTCH pathway. In addition, emerging new anti-NOTCH1 therapies include selective inhibition of NOTCH1 with anti-NOTCH1 antibodies and stapled peptides targeting the NOTCH transcriptional complex in the nucleus. PMID:23730497

  11. [Changes in the management of acute pancreatitis as related to its pathogenesis].

    PubMed

    Bodnár, Zoltán

    2005-03-13

    Although acute pancreatitis runs a benign self limiting course in 80% of cases, acute necrotizing form of it still remained a severe disease associated with significant morbidity and mortality. Severity assessment thus plays an important role in identifying patients with high risk of local and/or systemic complications. Locally, development of necrosis especially if it becomes infected accounts for high mortality, but systemic inflammatory response syndrome (SIRS) and multiple organ failure (MOF) following necrosis further increases the risk of fatal outcome. Several scoring systems, contrast-enhanced CT scan can help to recognize patients requiring early intensive management. Prophylactic systemic antibiotic treatment and nasojejunal feeding improves prognosis by decreasing the gut derived infection of necrosis. CT guided fine needle aspiration sample must be cultured to detect infection. Conservative therapy should be continued while necrosis remains sterile, but surgical and/or CT guided percutaneous catheter drainage is mandatory when infected necrosis developed. Results of therapeutic influence on the proinflammatory cytokine cascade in acute pancreatitis are still controversial. Enteral feeding seems to be the only proven tool in attenuating acute phase response and improving disease severity. PMID:15813188

  12. Molecular pathogenesis of plasminogen Hakodate: the second Japanese family case of severe type I plasminogen deficiency manifested late-onset multi-organic chronic pseudomembranous mucositis.

    PubMed

    Osaki, Tsukasa; Souri, Masayoshi; Song, Young-Seok; Izumi, Naohiro; Law, Ruby; Ichinose, Akitada

    2016-08-01

    A 64-year-old man first developed ligneous conjunctivitis at the age of 58 years after right pulmonary resection because of suspected cancer; otherwise, he had been healthy. Since then, he began to suffer from various forms of chronic pseudomembranous mucositis. Laboratory tests demonstrated that he had 7.8 % of plasminogen activity and 5.9 % of the normal antigen level. Thus, he was diagnosed as having severe type I plasminogen deficiency, making him the third case in Japan. DNA sequencing and PCR-restriction fragment length polymorphism analyses revealed that this patient was a compound heterozygote of a G-to-A missense mutation (G266E) in exon VIII and a g-to-a mutation at the obligatory splicing acceptor site in intron 12 (IVS12-1g>a). These two mutations were confirmed to be novel. Molecular modeling and splice site strength calculation predicted conformational disorder(s) for the Glu266 mutant and a drastic decrease in splicing efficiency for intron 12, respectively. Western blot analysis demonstrated that the patient contained a small amount of the normal-sized plasminogen protein. Mass spectrometric analysis of the patient's plasminogen revealed a peptide containing the wild-type Gly266 residue and no peptides with mutations at Glu266. However, he had never suffered from thrombosis. Low levels of fibrinogen/fibrin degradation products (FDP), D-dimer, and plasmin-α2-plasmin inhibitor complex clearly indicated a hypo-fibrinolytic condition. However, his plasma concentration of elastase-digested crosslinked FDPs was 4.8 U/mL, suggesting the presence of an on-going plasmin(ogen)-independent "alternative" fibrinolytic system, which may protect the patient from thrombosis. The patient has been free from recurrence of ligneous conjunctivitis for approximately 2.5 years. PMID:27193180

  13. Efficacy of famotidine in patients with acute gastric mucosal injury after continuous infusion of cisplatin plus vindesine.

    PubMed

    Mori, K; Tominaga, K; Yokoyama, K; Suga, Y; Kishiro, I; Tsurui, M

    1995-01-01

    The effect of famotidine (H2 blocker) on the gastroduodenal mucosal injury induced by chemotherapy in non-small-cell lung cancer patients was prospectively evaluated from the clinical and endoscopic findings obtained in a randomized double-blind study. The patients, who were administered cisplatin (25 mg/m2/day, continuous infusion, days 1-5) and vindesine (3 mg/m2, bolus, days 1 and 8), were randomized into two groups, those administered famotidine (40 mg/day, oral) and those administered the placebo. The patients were examined by gastroduodenoscopy within 7 days before and after chemotherapy. There were 27 patients in the famotidine group and 28 patients in the placebo group. The gastric mucosal score after chemotherapy was significantly lower in the famotidine group than in the placebo group (P < 0.01), and in the 42 patients without symptoms than in the 13 patients (placebo group: 8, famotidine group: 5) with upper gastrointestinal symptoms (P < 0.01). The pH of the gastric juice after the chemotherapy significantly decreased in the placebo group (P < 0.05), and was significantly lower in the placebo group than in the famotidine group (P = 0.01). The co-administration of famotidine was effective in the prevention and control of chemotherapy-induced gastric mucosal injury. PMID:7797602

  14. The Role of Different Monocyte Subsets in the Pathogenesis of Atherosclerosis and Acute Coronary Syndromes.

    PubMed

    Idzkowska, E; Eljaszewicz, A; Miklasz, P; Musial, W J; Tycinska, A M; Moniuszko, M

    2015-09-01

    The inflammation underlying both atherosclerosis and acute coronary syndromes is strongly related to monocyte-related actions. However, different monocyte subsets can play differential roles in the formation and destabilization of atherosclerotic plaque as well as healing of damaged myocardial tissue. Monocytes are currently being divided into three functionally distinct subsets with different levels of CD14 (cluster of differentiation 14) and CD16 expression. Thus, there are classical CD14++CD16-, intermediate CD14++CD16+ and non-classical CD14+CD16++ monocytes. Here, we summarize the current knowledge on complex activities of different monocyte subsets in atherosclerosis and acute coronary syndromes. Moreover, we discuss which monocyte subsets can serve either as predictive biomarkers of cardiovascular risk or as potential targets used in atherosclerosis and its complications. PMID:25997925

  15. Central role of neutrophil in the pathogenesis of severe acute pancreatitis

    PubMed Central

    Yang, Zhi-wen; Meng, Xiao-xiao; Xu, Ping

    2015-01-01

    Severe acute pancreatitis (SAP) is an acute abdominal disease with the strong systemic inflammatory response, and rapidly progresses from a local pancreatic damage into multiple organ dysfunction. For many decades, the contributions of neutrophils to the pathology of SAP were traditionally thought to be the chemokine and cytokine cascades that accompany inflammation. In this review, we focus mainly on those recently recognized aspects of neutrophils in SAP processes. First, emerging evidence suggests that therapeutic interventions targeting neutrophils significantly lower tissue damage and protect against the occurrence of pancreatitis. Second, trypsin activation promotes the initial neutrophils recruitment into local pancreas, and subsequently neutrophils infiltration in turn triggers trypsin production. Finally, neutrophils have the unique ability to release neutrophil extracellular traps even in the absence of pathogens. PMID:26249268

  16. Central role of neutrophil in the pathogenesis of severe acute pancreatitis.

    PubMed

    Yang, Zhi-Wen; Meng, Xiao-Xiao; Xu, Ping

    2015-11-01

    Severe acute pancreatitis (SAP) is an acute abdominal disease with the strong systemic inflammatory response, and rapidly progresses from a local pancreatic damage into multiple organ dysfunction. For many decades, the contributions of neutrophils to the pathology of SAP were traditionally thought to be the chemokine and cytokine cascades that accompany inflammation. In this review, we focus mainly on those recently recognized aspects of neutrophils in SAP processes. First, emerging evidence suggests that therapeutic interventions targeting neutrophils significantly lower tissue damage and protect against the occurrence of pancreatitis. Second, trypsin activation promotes the initial neutrophils recruitment into local pancreas, and subsequently neutrophils infiltration in turn triggers trypsin production. Finally, neutrophils have the unique ability to release neutrophil extracellular traps even in the absence of pathogens. PMID:26249268

  17. Novel roles of reactive oxygen species in the pathogenesis of acute myeloid leukemia

    PubMed Central

    Zhou, Fuling; Shen, Qiang; Claret, François X.

    2013-01-01

    It has become apparent that regulation of ROS is important in cell signaling and homeostasis. Accumulation of ROS triggers oxidative stress in various cell types and contributes to the development, progression, and persistence of cancer. Recent research has demonstrated that redox dysregulation caused by ROS promotes proliferation, differentiation, genomic, and epigenetic alterations; immune evasion; and survival in leukemic cells. ROS act as signaling molecules to regulate redox-sensitive transcriptional factors, enzymes, oncogenes, and other downstream effectors. Thus, a thorough understanding the role of ROS as key mediators in leukemogenesis is likely to provide opportunities for improved pharmacological intervention. In this review, we summarize the recent findings that support a role for ROS in the pathogenesis of AML and outline innovative approaches in the implementation of redox therapies for myeloid malignancies. PMID:23715741

  18. Molecular determinants of severe acute respiratory syndrome coronavirus pathogenesis and virulence in young and aged mouse models of human disease.

    PubMed

    Frieman, Matthew; Yount, Boyd; Agnihothram, Sudhakar; Page, Carly; Donaldson, Eric; Roberts, Anjeanette; Vogel, Leatrice; Woodruff, Becky; Scorpio, Diana; Subbarao, Kanta; Baric, Ralph S

    2012-01-01

    SARS coronavirus (SARS-CoV) causes severe acute respiratory tract disease characterized by diffuse alveolar damage and hyaline membrane formation. This pathology often progresses to acute respiratory distress (such as acute respiratory distress syndrome [ARDS]) and atypical pneumonia in humans, with characteristic age-related mortality rates approaching 50% or more in immunosenescent populations. The molecular basis for the extreme virulence of SARS-CoV remains elusive. Since young and aged (1-year-old) mice do not develop severe clinical disease following infection with wild-type SARS-CoV, a mouse-adapted strain of SARS-CoV (called MA15) was developed and was shown to cause lethal infection in these animals. To understand the genetic contributions to the increased pathogenesis of MA15 in rodents, we used reverse genetics and evaluated the virulence of panels of derivative viruses encoding various combinations of mouse-adapted mutations. We found that mutations in the viral spike (S) glycoprotein and, to a much less rigorous extent, in the nsp9 nonstructural protein, were primarily associated with the acquisition of virulence in young animals. The mutations in S likely increase recognition of the mouse angiotensin-converting enzyme 2 (ACE2) receptor not only in MA15 but also in two additional, independently isolated mouse-adapted SARS-CoVs. In contrast to the findings for young animals, mutations to revert to the wild-type sequence in nsp9 and the S glycoprotein were not sufficient to significantly attenuate the virus compared to other combinations of mouse-adapted mutations in 12-month-old mice. This panel of SARS-CoVs provides novel reagents that we have used to further our understanding of differential, age-related pathogenic mechanisms in mouse models of human disease. PMID:22072787

  19. Molecular Determinants of Severe Acute Respiratory Syndrome Coronavirus Pathogenesis and Virulence in Young and Aged Mouse Models of Human Disease

    PubMed Central

    Yount, Boyd; Agnihothram, Sudhakar; Page, Carly; Donaldson, Eric; Roberts, Anjeanette; Vogel, Leatrice; Woodruff, Becky; Scorpio, Diana; Subbarao, Kanta; Baric, Ralph S.

    2012-01-01

    SARS coronavirus (SARS-CoV) causes severe acute respiratory tract disease characterized by diffuse alveolar damage and hyaline membrane formation. This pathology often progresses to acute respiratory distress (such as acute respiratory distress syndrome [ARDS]) and atypical pneumonia in humans, with characteristic age-related mortality rates approaching 50% or more in immunosenescent populations. The molecular basis for the extreme virulence of SARS-CoV remains elusive. Since young and aged (1-year-old) mice do not develop severe clinical disease following infection with wild-type SARS-CoV, a mouse-adapted strain of SARS-CoV (called MA15) was developed and was shown to cause lethal infection in these animals. To understand the genetic contributions to the increased pathogenesis of MA15 in rodents, we used reverse genetics and evaluated the virulence of panels of derivative viruses encoding various combinations of mouse-adapted mutations. We found that mutations in the viral spike (S) glycoprotein and, to a much less rigorous extent, in the nsp9 nonstructural protein, were primarily associated with the acquisition of virulence in young animals. The mutations in S likely increase recognition of the mouse angiotensin-converting enzyme 2 (ACE2) receptor not only in MA15 but also in two additional, independently isolated mouse-adapted SARS-CoVs. In contrast to the findings for young animals, mutations to revert to the wild-type sequence in nsp9 and the S glycoprotein were not sufficient to significantly attenuate the virus compared to other combinations of mouse-adapted mutations in 12-month-old mice. This panel of SARS-CoVs provides novel reagents that we have used to further our understanding of differential, age-related pathogenic mechanisms in mouse models of human disease. PMID:22072787

  20. On the dynamics of acute EBV infection and the pathogenesis of infectious mononucleosis

    PubMed Central

    Hadinoto, Vey; Shapiro, Michael; Greenough, Thomas C.; Sullivan, John L.; Luzuriaga, Katherine

    2008-01-01

    Memory B cells latently infected with Epstein-Barr virus (mBLats) in the blood disappear rapidly on presentation with acute symptomatic primary infection (acute infectious mononucleosis [AIM]). They undergo a simple exponential decay (average half-life: 7.5 ± 3.7 days) similar to that of normal memory B cells. The cytotoxic T lymphocyte (CTL) response to immediate early (IE) lytic antigens (CTLIEs) also decays over this time period, but no such correlation was observed for the CTL response to lytic or latent antigens or to the levels of virions shed into saliva. We have estimated the average half-life of CTLIEs to be 73 (± 23) days. We propose that cycles of infection and reactivation occur in the initial stages of infection that produce high levels of mBLats in the circulation. Eventually the immune response arises and minimizes these cycles leaving the high levels of mBLats in the blood to decay through simple memory B-cell homeostasis mechanisms. This triggers the cells to reactivate the virus whereupon most are killed by CTLIEs before they can release virus and infect new cells. The release of antigens caused by this large-scale destruction of infected cells may trigger the symptoms of AIM and be a cofactor in other AIM-associated diseases. PMID:17991806

  1. Effects of acute chemotherapy-induced mucositis on spontaneous behaviour and the grimace scale in laboratory rats.

    PubMed

    Whittaker, A L; Leach, M C; Preston, F L; Lymn, K A; Howarth, G S

    2016-04-01

    Intestinal mucositis is a frequent side-effect of chemotherapy treatment. Many oncological research programs aim to identify novel treatments for this distressing condition, and these programs frequently use rat models. Little is known about the presence and progression of pain in these models and how this can best be treated by analgesic therapy. We used a number of behaviour-based methods of pain assessment to determine which tools were best suited for pain identification. Baseline measures for behavioural assessment, rat grimace score and sociability were determined through analysis of continuously recorded video data and an applied social interaction test (n = 16). Mucositis was then induced by intraperitoneal injection of 5-fluorouracil (150 mg/kg) and further behavioural analyses undertaken. An assessment of enrichment interaction was also made by determining the mass of a plastic chew toy gnawed both pre- and post-chemotherapy injection. Behavioural scoring was performed 1, 6, 12, 24 and 48 h after injection, with facial expression being scored at the 12, 24 and 48 h time-points. Sociability testing was performed once during the post-injection period. No significant differences were found in grimace scores between baseline and later daily measures. Behaviours similar to those previously reported post-laparotomy were observed. Writhing, twitching and back-arching behaviours were most evident in rats affected by mucositis and were increased in frequency (respectivePvalues: 0.002, 0.004 and 0.008) 48 h after chemotherapy injection compared with baseline, implying that pain onset occurred around this time-point. Social investigatory behaviour was also increased (P = 0.002) following disease onset. Each day, rats post-5FU injection gnawed a greater percentage of their nylabone enrichment by weight than the saline-injected control rats (P = 0.046). These data suggest that, of the tools tested, behavioural assessment scoring may find greatest

  2. The role of acetaldehyde in the pathogenesis of acute alcoholic pancreatitis.

    PubMed Central

    Nordback, I H; MacGowan, S; Potter, J J; Cameron, J L

    1991-01-01

    Acetaldehyde (AA), the first product of ethanol metabolism, has been suggested as an important mediator in alcoholic pancreatitis, but experimental evidence has not been convincing. Prior work using the isolated perfused canine pancreas preparation has suggested that toxic oxygen metabolites generated by xanthine oxidase (XO) may mediate the early injury in pancreatitis. Xanthine oxidase is capable of oxidizing AA, and during this oxidation free radicals are released. The hypothesis that acute alcoholic pancreatitis may be initiated by AA in the presence of active XO (converted from xanthine dehydrogenase [XD]) was tested in the authors' experimental preparation by converting XD to XO by a period of ischemia, and infusing AA. Control preparations remained normal throughout the 4-hour perfusion (weight gain, 7 +/- 4 g; amylase activity, 1162 +/- 202 U/dL). One hour of ischemia or infusion of AA at 25 mg/hr or at 50 mg/hr without ischemia did not induce changes in the preparation. Acetaldehyde at 250 mg/hr induced minimal edema and weight gain (16 +/- 4 g; p less than 0.05), but not significant hyperamylasemia. Changes also were not observed when 1-hour ischemia was followed by a bolus of ethanol (1.5 g) or sodium acetate (3.0 g), or by infusion of 25 mg/hr of AA. One hour of ischemia followed by infusion of AA at 50 mg/hr or at 250 mg/hr induced edema, hemorrhage, weight gain (22 +/- 7 g [p less than 0.05] and 26 +/- 17 g [p less than 0.05]) and hyperamylasemia (2249 +/- 1034 U/dL [p less than 0.05] and 2602 +/- 1412 U/dL [p less than 0.05]). Moreover infusion of AA at 250 mg/hr after 2 hours of ischemia potentiated the weight gain (62 +/- 20 g versus 30 +/- 14 g [p less than 0.05]), but not the hyperamylasemia (3404 +/- 589 U/dL versus 2862 +/- 1525 U/dL) as compared with 2 hours of ischemia alone. Pancreatitis induced by 1 hour of ischemia followed by AA at 50 mg/hr could be inhibited by pretreatment with the free radical scavengers superoxide dismutase and

  3. Mouse Models for the Study of Mucosal Vaccination Against Otitis Media

    PubMed Central

    Sabirov, Albert; Metzger, Dennis W.

    2008-01-01

    Otitis media (OM) is one of the most common infectious diseases in humans. The pathogenesis of OM involves nasopharyngeal colonization (NP) and retrograde ascension of the pathogen up the Eustachian tube into the middle ear (ME). Due to increasing rates of antibiotic resistance, there is an urgent need for vaccines to prevent infections caused by the most common causes of bacterial OM, including nontypeable Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis. Current vaccine strategies aim to diminish bacterial NP carriage, thereby reducing the likelihood of developing acute OM. To be effective, vaccination should induce local mucosal mmunity both in the ME and in the NP. Studies in animal models have demonstrated that the intranasal route of vaccination is particularly effective at inducing immune responses in the nasal passage and ME for protection against OM. The mouse is increasingly used in these models, because of the availability of murine reagents and the existence of technology to manipulate murine models of disease immunologically and genetically. Previous studies confirmed the suitability of the mouse as a model for inflammatory processes in acute OM. Here, we discuss various murine models of OM and review the applicability of these models to assess the efficacy of mucosal vaccination and the mechanisms responsible for protection. In addition, we discuss various mucosal vaccine antigens, mucosal adjuvants and mucosal delivery systems. PMID:18295938

  4. Primary mucosal melanomas: a comprehensive review

    PubMed Central

    Mihajlovic, Marija; Vlajkovic, Slobodan; Jovanovic, Predrag; Stefanovic, Vladisav

    2012-01-01

    Primary mucosal melanomas arise from melanocytes located in mucosal membranes lining respiratory, gastrointestinal and urogenital tract. Although a majority of mucosal melanomas originate from the mucosa of the nasal cavity and accessory sinuses, oral cavity, anorectum, vulva and vagina, they can arise in almost any part of mucosal membranes. Most of mucosal melanomas occur in occult sites, which together with the lack of early and specific signs contribute to late diagnosis, and poor prognosis. Because of their rareness the knowledge about their pathogenesis and risk factors is insufficient, and also there are not well established protocols for staging and treatment of mucosal melanomas. Surgery is the mainstay of treatment, with trends toward more conservative treatment since radical surgery did not show an advantage for survival. Radiotherapy can provide better local control in some locations, but did not show improvement in survival. There is no effective systemic therapy for these aggressive tumors. Compared with cutaneous and ocular melanoma, mucosal melanomas have lowest percent of five-year survival. Recently revealed molecular changes underlying mucosal melanomas offer new hope for development of more effective systemic therapy for mucosal melanomas. Herein we presented a comprehensive review of various locations of primary melanoma along mucosal membranes, their epidemiological and clinical features, and treatment options. We also gave a short comparison of some characteristics of cutaneous and mucosal melanomas. PMID:23071856

  5. An overview of animal models for investigating the pathogenesis and therapeutic strategies in acute hepatic failure

    PubMed Central

    Tuñón, María Jesús; Alvarez, Marcelino; Culebras, Jesús M; González-Gallego, Javier

    2009-01-01

    Acute hepatic failure (AHF) is a severe liver injury accompanied by hepatic encephalopathy which causes multiorgan failure with an extremely high mortality rate, even if intensive care is provided. Management of severe AHF continues to be one of the most challenging problems in clinical medicine. Liver transplantation has been shown to be the most effective therapy, but the procedure is limited by shortage of donor organs. Although a number of clinical trials testing different liver assist devices are under way, these systems alone have no significant effect on patient survival and are only regarded as a useful approach to bridge patients with AHF to liver transplantation. As a result, reproducible experimental animal models resembling the clinical conditions are still needed. The three main approaches used to create an animal model for AHF are: surgical procedures, toxic liver injury and infective procedures. Most common models are based on surgical techniques (total/partial hepatectomy, complete/transient devascularization) or the use of hepatotoxic drugs (acetaminophen, galactosamine, thioacetamide, and others), and very few satisfactory viral models are available. We have recently developed a viral model of AHF by means of the inoculation of rabbits with the virus of rabbit hemorrhagic disease. This model displays biochemical and histological characteristics, and clinical features that resemble those in human AHF. In the present article an overview is given of the most widely used animal models of AHF, and their main advantages and disadvantages are reviewed. PMID:19575487

  6. A murine model of obesity implicates the adipokine milieu in the pathogenesis of severe acute pancreatitis.

    PubMed

    Zyromski, Nicholas J; Mathur, Abhishek; Pitt, Henry A; Lu, Debao; Gripe, John T; Walker, Julia J; Yancey, Kyle; Wade, Terence E; Swartz-Basile, Deborah A

    2008-09-01

    Obesity is clearly an independent risk factor for increased severity of acute pancreatitis (AP), although the mechanisms underlying this association are unknown. Adipokines (including leptin and adiponectin) are pleiotropic molecules produced by adipocytes that are important regulators of the inflammatory response. We hypothesized that the altered adipokine milieu observed in obesity contributes to the increased severity of pancreatitis. Lean (C57BL/6J), obese leptin-deficient (LepOb), and obese hyperleptinemic (LepDb) mice were subjected to AP by six hourly intraperitoneal injections of cerulein (50 microg/kg). Severity of AP was assessed by histology and by measuring pancreatic concentration of the proinflammatory cytokines IL-1beta and IL-6, the chemokine MCP-1, and the marker of neutrophil activation MPO. Both congenitally obese strains of mice developed significantly more severe AP than wild-type lean animals. Severity of AP was not solely related to adipose tissue volume: LepOb mice were heaviest; however, LepDb mice developed the most severe AP both histologically and biochemically. Circulating adiponectin concentrations inversely mirrored the severity of pancreatitis. These data demonstrate that congenitally obese mice develop more severe AP than lean animals when challenged by cerulein hyperstimulation and suggest that alteration of the adipokine milieu exacerbates the severity of AP in obesity. PMID:18583460

  7. Pathogenesis and early management of non-ST-segment elevation acute coronary syndromes.

    PubMed

    Ayala, Tomas H; Schulman, Steven P

    2006-02-01

    NSTE ACS is a clinically significant problem. Endothelial dysfunction triggered by traditional cardiovascular risk factors (and perhaps by other as yet unidentified risks) in the susceptible host leads to the formation and development of atherosclerotic plaque. Inflammatory mediators and mechanical stresses contribute to plaque rupture by disrupting the protective fibrous cap. In about 25% of patients who have ACS, typically those who are younger, female, or smokers, plaque erosion seems to be the main underlying pathologic mechanism. Endothelial alteration, inflammation,or exposure of the lipid core results in the release of TF, vWF, and PAF. The release of these factors leads to platelet activation and aggregation as well as to the formation of a fibrin clot, resulting in arterial thrombosis that occludes the vessel. A variety of factors, including circulating catecholamines, LDL levels, blood glucose levels, and systemic thrombogenic factors, can affect the extent and stability of the thrombus, thereby determining whether the occlusion is complete and fixed, labile and nonocclusive (NSTE ACS),or clinically silent resulting in a mural thrombus and plaque growth. The acute treatment of NSTEACS is directed at interrupting the prothrombotic environment surrounding the ruptured plaque; thus, antiplatelet agents such as aspirin, clopidogrel, and glycoprotein IIb/IIla receptor antagonists,as well as anticoagulants such as heparin, are the mainstays of early therapy. PMID:16326254

  8. Israeli Acute Paralysis Virus: Epidemiology, Pathogenesis and Implications for Honey Bee Health

    PubMed Central

    Chen, Yan Ping; Pettis, Jeffery S.; Corona, Miguel; Chen, Wei Ping; Li, Cong Jun; Spivak, Marla; Visscher, P. Kirk; DeGrandi-Hoffman, Gloria; Boncristiani, Humberto; Zhao, Yan; vanEngelsdorp, Dennis; Delaplane, Keith; Solter, Leellen; Drummond, Francis; Kramer, Matthew; Lipkin, W. Ian; Palacios, Gustavo; Hamilton, Michele C.; Smith, Barton; Huang, Shao Kang; Zheng, Huo Qing; Li, Ji Lian; Zhang, Xuan; Zhou, Ai Fen; Wu, Li You; Zhou, Ji Zhong; Lee, Myeong-L.; Teixeira, Erica W.; Li, Zhi Guo; Evans, Jay D.

    2014-01-01

    Israeli acute paralysis virus (IAPV) is a widespread RNA virus of honey bees that has been linked with colony losses. Here we describe the transmission, prevalence, and genetic traits of this virus, along with host transcriptional responses to infections. Further, we present RNAi-based strategies for limiting an important mechanism used by IAPV to subvert host defenses. Our study shows that IAPV is established as a persistent infection in honey bee populations, likely enabled by both horizontal and vertical transmission pathways. The phenotypic differences in pathology among different strains of IAPV found globally may be due to high levels of standing genetic variation. Microarray profiles of host responses to IAPV infection revealed that mitochondrial function is the most significantly affected biological process, suggesting that viral infection causes significant disturbance in energy-related host processes. The expression of genes involved in immune pathways in adult bees indicates that IAPV infection triggers active immune responses. The evidence that silencing an IAPV-encoded putative suppressor of RNAi reduces IAPV replication suggests a functional assignment for a particular genomic region of IAPV and closely related viruses from the Family Dicistroviridae, and indicates a novel therapeutic strategy for limiting multiple honey bee viruses simultaneously and reducing colony losses due to viral diseases. We believe that the knowledge and insights gained from this study will provide a new platform for continuing studies of the IAPV–host interactions and have positive implications for disease management that will lead to mitigation of escalating honey bee colony losses worldwide. PMID:25079600

  9. Israeli acute paralysis virus: epidemiology, pathogenesis and implications for honey bee health.

    PubMed

    Chen, Yan Ping; Pettis, Jeffery S; Corona, Miguel; Chen, Wei Ping; Li, Cong Jun; Spivak, Marla; Visscher, P Kirk; DeGrandi-Hoffman, Gloria; Boncristiani, Humberto; Zhao, Yan; vanEngelsdorp, Dennis; Delaplane, Keith; Solter, Leellen; Drummond, Francis; Kramer, Matthew; Lipkin, W Ian; Palacios, Gustavo; Hamilton, Michele C; Smith, Barton; Huang, Shao Kang; Zheng, Huo Qing; Li, Ji Lian; Zhang, Xuan; Zhou, Ai Fen; Wu, Li You; Zhou, Ji Zhong; Lee, Myeong-L; Teixeira, Erica W; Li, Zhi Guo; Evans, Jay D

    2014-07-01

    Israeli acute paralysis virus (IAPV) is a widespread RNA virus of honey bees that has been linked with colony losses. Here we describe the transmission, prevalence, and genetic traits of this virus, along with host transcriptional responses to infections. Further, we present RNAi-based strategies for limiting an important mechanism used by IAPV to subvert host defenses. Our study shows that IAPV is established as a persistent infection in honey bee populations, likely enabled by both horizontal and vertical transmission pathways. The phenotypic differences in pathology among different strains of IAPV found globally may be due to high levels of standing genetic variation. Microarray profiles of host responses to IAPV infection revealed that mitochondrial function is the most significantly affected biological process, suggesting that viral infection causes significant disturbance in energy-related host processes. The expression of genes involved in immune pathways in adult bees indicates that IAPV infection triggers active immune responses. The evidence that silencing an IAPV-encoded putative suppressor of RNAi reduces IAPV replication suggests a functional assignment for a particular genomic region of IAPV and closely related viruses from the Family Dicistroviridae, and indicates a novel therapeutic strategy for limiting multiple honey bee viruses simultaneously and reducing colony losses due to viral diseases. We believe that the knowledge and insights gained from this study will provide a new platform for continuing studies of the IAPV-host interactions and have positive implications for disease management that will lead to mitigation of escalating honey bee colony losses worldwide. PMID:25079600

  10. Do we know enough about the immune pathogenesis of acute coronary syndromes to improve clinical practice?

    PubMed

    Matusik, Pawel; Guzik, Bartlomiej; Weber, Christian; Guzik, Tomasz J

    2012-09-01

    Morbidities related to atherosclerosis, such as acute coronary syndromes (ACS) including unstable angina and myocardial infarction, remain leading causes of mortality. Unstable plaques are inflamed and infiltrated with macrophages and T lymphocytes. Activated dendritic cells interact with T cells, yielding predominantly Th1 responses involving interferon-gamma (IFN-γ) and tumour necrosis factor-alpha (TNF-α), while the role of interleukin 17 (IL-17) is questionable. The expansion of CD28nullCD4 or CD8 T cells as well as pattern recognition receptors activation (especially Toll-like receptors; TLR2 and TLR4) is characteristic for unstable plaque. Inflammation modifies platelet and fibrin clot characteristics, which are critical for ACS. Understanding of the inflammatory mechanisms of atherothrombosis, bridging inflammation, oxidative stress and immune regulation, will allow for the detection of subjects at risk, through the use of novel biomarkers and imaging techniques including intravascular ultrasound, molecular targeting, magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET). Moreover, understanding the specific inflammatory pathways of plaque rupture and atherothrombosis may allow for immunomodulation of ACS. Statins and anti-platelet drugs are anti-inflammatory, but importance of immune events in ACS warrants the introduction of novel, specific treatments directed either on cytokines, TLRs or inflammasomes. While the prime time for the introduction of immunologically inspired diagnostic tests and treatments for atherosclerosis have not come yet, we are closer than ever before to finally being able to benefit from this vast body of experimental and clinical evidence. This paper provides a comprehensive review of the role of the immune system and inflammation in ACS. PMID:22872109

  11. Mechanism of the beneficial effects of dantrolene sodium on ethanol-induced acute gastric mucosal injury in rats.

    PubMed

    Büyükokuroğlu, Mehmet Emin; Taysi, Seyithan; Polat, Fevzi; Göçer, Fatma

    2002-05-01

    In our study, we examined anti-ulcerogen and antioxidant effects of dantrolene sodium on ethanol-induced gastric lesions in rats. Dantrolene sodium was administered intraperitoneally (i.p.) in several doses, and famotidine was used at a dose of 20 mg kg (-1). It was found that pretreatment with dantrolene sodium at doses of 1, 5 and 10 mg kg(-1) significantly reduced ethanol-induced gastric damage and malondialdehyde levels, and significantly increased antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. We conclude that dantrolene sodium clearly has antioxidant properties and that the protective effect of dantrolene sodium against ethanol-induced gastric mucosal lesion, at least in part, depends upon the reduction in the lipid peroxidation and an increase in the activity of antioxidant enzymes SOD and GSH-Px. PMID:12123631

  12. Mucosal immunoglobulins.

    PubMed

    Woof, Jenny M; Mestecky, Jiri

    2005-08-01

    Due to their vast surface area, the mucosal surfaces of the body represent a major site of potential attack by invading pathogens. The secretions that bathe mucosal surfaces contain significant levels of immunoglobulins (Igs), which play key roles in immune defense of these surfaces. IgA is the predominant antibody class in many external secretions and has many functional attributes, both direct and indirect, that serve to prevent infective agents such as bacteria and viruses from breaching the mucosal barrier. This review details current understanding of the structural and functional characteristics of IgA, including interaction with specific receptors (such as Fc(alpha)RI, Fc(alpha)/microR, and CD71) and presents examples of the means by which certain pathogens circumvent the protective properties of this important Ig. PMID:16048542

  13. Transfusion-Related Acute Lung Injury: Incidence, Pathogenesis and the Role of Multicomponent Apheresis in Its Prevention.

    PubMed

    Popovsky, Mark A

    2008-01-01

    SUMMARY: Although transfusion-related acute lung injury (TRALI) is now appreciated as the most common cause of death from transfusion, its incidence remains unknown. The most frequently cited figure is 1:5,000 plasma-containing components. Certain patient groups may be at significantly higher risk. TRALI is both underdiagnosed and un-derreported. It is misdiagnosed as transfusion-associated circulatory overload. Several mechanisms have been proposed for its pathogenesis-leukocyte antibodies and the 2-hit model. These may overlap, and both involve transfusion of leukocyte antibodies. Passive transfusion of leukocyte antibodies is strongly associated with TRALI; these are identified in 60-85% of cases. Multiparous blood donors are the most frequent source of these antibody-containing components. The antibodies are HLA class I and II and/or granulocyte-specific. In 50% of cases the antibody corresponds to an epitope in the patient. HLA class I antibodies have been shown to prime and activate neutrophils. Clinical reports and animal models link HNA-3a antibodies with severe lung injury. A number of TRALI prevention and risk mitigation strategies have been proposed. In the UK and the USA, these strategies have centered upon excluding 'high risk' (HLA/HNA antibody containing) plasma from fresh frozen plasma and platelet products. Multicomponent apheresis collection of platelets, plasma and red blood cells is a means of accomplishing this objective. PMID:21512631

  14. Antioxidant Properties and Gastroprotective Effects of 2-(Ethylthio)Benzohydrazones on Ethanol-Induced Acute Gastric Mucosal Lesions in Rats

    PubMed Central

    Ariffin, Azhar; Abdulla, Mahmood A.; Abdullah, Zanariah

    2016-01-01

    A series of new 2-(ethylthio)benzohydrazone derivatives (1–6) were prepared and characterised by IR, 1H NMR, and 13C NMR spectroscopy and mass spectrometry. The newly prepared compounds were screened for their in vitro antioxidant activities using free radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Among them, most powerful antioxidant, compound 1 has been selected in order to illustrate anti-ulcer effect on ethanol-induced gastric mucosal lesions in rats. Four groups of Sprague Dawley rats were respectively treated with 10% Tween 20 as ulcer control group, 20 mg/kg omeprazole as reference group, 50 mg/kg and 100 mg/kg compound 1 as experimental animals. Macroscopically, ulcer control group showed extensive hemorrhagic lesions of gastric mucosa compared with omeprazole or compound 1. Rats pre-treated with compound 1 showed increased in gastric pH and gastric mucus. Histologically, ulcer control group showed severe damage to gastric mucosa with edema and leucocytes infiltration of submucosal layer. In immunohistochemical analysis, rats which were pre-treated with compound 1 showed up-regulation of HSP70 and down-regulation of Bax proteins. In conclusion, the gastroprotective effect of compound 1 may be due to its antioxidant activity, and/or due to up-regulation of HSP70 and down-regulation of Bax protein in stained tissue section. PMID:27272221

  15. Endoscopic measurements of canine colonic mucosal blood flow using hydrogen gas clearance

    SciTech Connect

    Soybel, D.I.; Wan, Y.L.; Ashley, S.W.; Yan, Z.Y.; Ordway, F.S.; Cheung, L.Y.

    1987-04-01

    We have examined the feasibility of hydrogen (H/sub 2/) clearance for endoscopic measurements of colonic mucosal blood flow in anesthetized dogs. In 6 animals, measurements of H2 clearance did not differ significantly in different regions of the sigmoid colon and they were highly reproducible on different days. In a total of 12 dogs, measurements of H2 clearance correlated closely with those obtained using radioactive microspheres under resting conditions and, in 4 dogs, during infusion of vasopressin. In 8 dogs, ligation of the major arteries supplying the sigmoid colon resulted in an acute 60% decrease in sigmoid mucosal blood flow; however, in 5 animals that survived the procedure, mucosal blood flow returned nearly to control levels as early as 3 days after operation. Endoscopic H/sub 2/ clearance thus appears to be feasible for measuring mucosal blood flow in the colon. Serial measurements of H/sub 2/ clearance may prove useful in characterizing the role of mucosal blood flow in the pathogenesis of various forms of human colonic disease.

  16. Identification of the interaction of VP1 with GM130 which may implicate in the pathogenesis of CVB3-induced acute pancreatitis

    PubMed Central

    Li, Xiuzhen; Xia, Yanhua; Huang, Shengping; Liu, Fadi; Ying, Ying; Xu, Qiufang; Liu, Xin; Jin, Guili; Papasian, Christopher J.; Chen, Jack; Fu, Mingui; Huang, Xiaotian

    2015-01-01

    Coxsackievirus B3 (CVB3) is a causative agent of viral myocarditis, pancreatitis, and meningitis in humans. Although the susceptibility of CVB3-induced acute pancreatitis is age-dependent, the underlying mechanisms remain unclear. Here we identified the host factor Golgi matrix protein 130 (GM130) as a novel target of CVB3 during CVB3-induced acute pancreatitis. The viral protein VP1 interacted with GM130, disrupted GM130-GRASP65 complexes, and caused GM130 degradation, which may lead to disruption of the Golgi ribbon and development of acute pancreatitis in mice. Interestingly, the expression level of GM130 in mouse pancreas was age-dependent, which was nicely correlated with the age-associated susceptibility of CVB3-induced acute pancreatitis. Furthermore, interference RNA-mediated knockdown of GM130 significantly reduced CVB3 replication in HeLa cells. Taken together, the study identified GM130 as a novel target of CVB3, which may implicate in the pathogenesis of CVB3-induced acute pancreatitis. PMID:26314804

  17. Targeting α4β7 integrin reduces mucosal transmission of SIV and protects GALT from infection

    PubMed Central

    Byrareddy, Siddappa N.; Kallam, Brianne; Arthos, James; Cicala, Claudia; Nawaz, Fatima; Hiatt, Joseph; Kersh, Ellen N.; McNicholl, Janet M.; Hanson, Debra; Reimann, Keith A.; Brameier, Markus; Walter, Lutz; Rogers, Kenneth; Mayne, Ann E.; Dunbar, Paul; Villinger, Tara; Little, Dawn; Parslow, Tristram G.; Santangelo, Philip J.; Villinger, Francois; Fauci, Anthony S.; Ansari, Aftab A.

    2014-01-01

    α4β7 integrin expressing CD4+ T cells preferentially traffic to gut-associated lymphoid tissues (GALT) and play a key role in HIV/SIV pathogenesis. The administration of an anti-α4β7 monoclonal antibody during acute infection protects macaques from transmission following repeated low-dose intra-vaginal challenges with SIVmac251. In treated animals that became infected the GALT was significantly protected and CD4+ T–cell numbers were maintained. Thus, targeting α4β7 reduces mucosal transmission of SIV in macaques. PMID:25419708

  18. In Vivo and Cadaver Studies of the Canalicular/Lacrimal Sac Mucosal Folds

    PubMed Central

    You, Yongsheng; Cao, Jing; Zhang, Xiaogang; Wu, Wencan; Xiao, Tianlin

    2016-01-01

    Purpose. The study aimed to investigate canalicular/lacrimal sac mucosal folds (CLS-MFs) in vivo and in cadavers in order to explore their functional roles in the lacrimal drainage system. Method. The observations of CLS-MFs in vivo were performed on 16 patients with chronic dacryocystitis after undergoing an endonasal endoscopic dacryocystorhinostomy (EE-DCR). The lacrimal sacs and common canaliculi of 19 adult cadavers were dissected. The opening/closing of an orifice and mucosal fold was recorded. All of the specimens were subjected to a histological examination. Results. The upper and lower lacrimal canaliculi in all of the samples united to form a common canaliculus that opened to the lacrimal sac. CLS-MFs were observed in 10 of the 16 patients (62.5%) and 9 of the 19 cadavers (47.4%). The orifices or mucosal folds could be opened or closed when related muscles contracted or relaxed. Histological sections showed a mucosal fold at one side of an orifice. Conclusion. Common canaliculus is the most common type that the canaliculus opens to lacrimal sac. CLS-MFs exist in a certain ratio that can be opened/closed with the movement of the orifices. They may be involved in the drainage of tears or the pathogenesis of acute dacryocystitis or lacrimal sac mucocele. PMID:27242921

  19. Replacing the acetyl linkage in aspirin with choline and magnesium moieties reduces the occurrence of gastric mucosal injury.

    PubMed

    Danesh, B J; Nelson, L M; Russell, R I; Docherty, C

    1987-02-01

    The acetyl moiety in aspirin (acetyl salicylic acid: ASA) is considered to play a major part in the pathogenesis of ASA-induced mucosal injury. At equivalent salicylate doses and pH values, the induction of acute gastric mucosal haemorrhagic erosions in rats by ASA and choline magnesium trisalicylate (CMT), a new non-acetylated salicylate, with and without the potentiating damaging effect of taurodeoxycholic acid (TDCA) were compared. Test solutions were administered by per oral intubation to five groups of fasting Sprague-Dawley rats (n = 24). Gastric mucosa were examined after 4 hours and mucosal injury assessed by a lesion-scoring system. The incidence and severity (median lesion scores with quartiles) of the lesions were 83% and 13 (7:20) respectively for ASA (128 mg kg-1) compared with 17% and 0 (0:0) for CMT (128 mg kg-1) (P less than 0.001 and P less than 0.001). TDCA increased mucosal damage to 100% and 29 (20:34) for ASA compared with 30% and 0 (0:4) for CMT (P less than 0.001) and P less than 0.001). Serum salicylate levels (median values of 1.4 for ASA and 1.5 mmol litre-1 for CMT) were not significantly different. It is concluded that replacing the acetyl moiety in ASA with choline and magnesium moieties reduces the ASA-induced mucosal injury, without affecting blood salicylate concentrations. PMID:2979212

  20. Protective effects of alginate–chitosan microspheres loaded with alkaloids from Coptis chinensis Franch. and Evodia rutaecarpa (Juss.) Benth. (Zuojin Pill) against ethanol-induced acute gastric mucosal injury in rats

    PubMed Central

    Wang, Qiang-Song; Zhu, Xiao-Ning; Jiang, Heng-Li; Wang, Gui-Fang; Cui, Yuan-Lu

    2015-01-01

    Zuojin Pill (ZJP), a traditional Chinese medicine formula, consists of Coptis chinensis Franch. and Evodia rutaecarpa (Juss.) Benth. in a ratio of 6:1 (w/w) and was first recorded in “Danxi’s experiential therapy” for treating gastrointestinal disorders in the 15th century. However, the poor solubility of alkaloids from ZJP restricted the protective effect in treating gastritis and gastric ulcer. The aim of the study was to investigate the protective mechanism of mucoadhesive microspheres loaded with alkaloids from C. chinensis Franch. and E. rutaecarpa (Juss.) Benth. on ethanol-induced acute gastric mucosal injury in rats. Surface morphology, particle size, drug loading, encapsulation efficiency, in vitro drug release, mucoadhesiveness, and fluorescent imaging of the microspheres in gastrointestinal tract were studied. The results showed that the mucoadhesive microspheres loaded with alkaloids could sustain the release of drugs beyond 12 hours and had gastric mucoadhesive property with 82.63% retention rate in vitro. The fluorescence tracer indicated high retention of mucoadhesive microspheres within 12 hours in vivo. The mucoadhesive microspheres loaded with alkaloids could reduce the gastric injury by decreasing the mucosal lesion index, increasing the percentage of inhibition and increasing the amount of mucus in the gastric mucosa in an ethanol-induced gastric mucosal injury rat model. Moreover, the mucoadhesive microspheres loaded with alkaloids reduce the inflammatory response by decreasing the levels of tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), downregulating the mRNA expression of inducible nitric oxide synthase, TNF-α, and IL-1β in gastric mucosa. All the results indicate that mucoadhesive microspheres loaded with alkaloids could not only increase the residence time of alkaloids in rat stomach, but also exert gastroprotective effects through reducing the inflammatory response on ethanol-induced gastric mucosal damage. Thus

  1. Neutrophil elastase mediates acute pathogenesis and is a determinant of long-term behavioral recovery after traumatic injury to the immature brain

    PubMed Central

    Semple, Bridgette D; Trivedi, Alpa; Gimlin, Kayleen; Noble-Haeusslein, Linda J

    2014-01-01

    , WT mice treated acutely with the NE inhibitor showed no long-term behavioral or structural improvements. Together, these findings validate the central role of NE in both acute pathogenesis and chronic functional recovery, and support future exploration of the therapeutic window, taking into account the prolonged period of neutrophil trafficking into the injured immature brain. PMID:25497734

  2. Neutrophil elastase mediates acute pathogenesis and is a determinant of long-term behavioral recovery after traumatic injury to the immature brain.

    PubMed

    Semple, Bridgette D; Trivedi, Alpa; Gimlin, Kayleen; Noble-Haeusslein, Linda J

    2015-02-01

    , WT mice treated acutely with the NE inhibitor showed no long-term behavioral or structural improvements. Together, these findings validate the central role of NE in both acute pathogenesis and chronic functional recovery, and support future exploration of the therapeutic window, taking into account the prolonged period of neutrophil trafficking into the injured immature brain. PMID:25497734

  3. Oral mucositis - self-care

    MedlinePlus

    Cancer treatment - mucositis; Cancer treatment - mouth pain; Cancer treatment - mouth sores; Chemotherapy - mucositis; Chemotherapy - mouth pain; Chemotherapy - mouth sores; Radiation therapy - mucositis; Radiation therapy - mouth pain; Radiation ...

  4. Sirt1-Positive Lymphocytes in Acute Cellular Cardiac Allograft Rejection: Contributor to Pathogenesis and a Therapeutic Target.

    PubMed

    Welsh, Kerry J; Zhao, Bihong; Buja, L Maximilian; Brown, Robert E

    2016-01-01

    Cardiac allograft rejection remains a problem, despite advances with immunosuppressants. Understanding the mechanisms behind rejection is essential for developing targeted therapies. The goal of this investigation is to explore Sirtuin 1 (Sirt1) as a therapeutic target for cardiac allograft rejection. Thirteen endomyocardial biopsy specimens with acute cellular rejection (grade 2R or 3R) were selected. CD3, CD4, CD8, CD20, CD68, T-cell intracytoplasmic antigen (TIA-1), and Sirt1 expressions were determined by immunohistochemical stains. Comparison of Sirt1 expression was made with 10 cases of grade 0R and grade 1R. Quantitative image analysis was performed. There were 2 cases of grade 3R and 11 cases of grade 2R acute cellular rejection. Sirtuin 1 expression was present in the majority of mononuclear cells (median percentage, 73.5; interquartile range, 51.2-100%); staining was also observed in cardiomyocytes. Twelve of the 13 cases (92.3%) had an elevated CD8/FoxP3 ratio, coinciding with acute cellular rejection. Sirtuin 1 expression in the nuclei of FoxP3+ cells can lead to deacetylation and inactivation of FoxP3 rendering the T-suppressor cells inactive and promoting acute cellular rejection. The use of a Sirt1 inhibitor may be a therapeutic option in expanding the functionality of the FoxP3+ T-suppressor cells and moderating the severity of such rejection. PMID:26771391

  5. Israeli acute paralysis virus: epidemiology, pathogenesis and implications for honey bee health and Colony Collapse Disorder (CCD)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Israeli acute paralysis virus (IAPV) is a widespread RNA virus that was linked with honey bee Colony Collapse Disorder (CCD), the sudden and massive die-off of honey bee colonies in the U.S. in 2006-2007. Here we describe the transmission, prevalence and genetic diversity of IAPV, host transcripti...

  6. Antibodies against acute phase proteins and their functions in the pathogenesis of disease: a collective profile of 25 different antibodies.

    PubMed

    Lakota, Katja; Zigon, Polona; Mrak-Poljsak, Katjusa; Rozman, Blaz; Shoenfeld, Yehuda; Sodin-Semrl, Snezna

    2011-10-01

    The acute phase response is a defense system in which the innate immune response is activated following injury or infection. Positive and negative acute phase proteins (APPs) are crucial for protecting the host organism, as well as returning it to homeostatic levels, the first with elevated concentrations and the latter with decreased concentrations during the acute phase. Reports about the presence of antibodies against APPs are known, however their individual, as well as potentially collective, pathological or physiological roles are still emerging. Some of these autoantibodies are specifically connected with diseases (such as pancreatic secretory trypsin inhibitor and C3, C4 nephritic factors), while others have been reported as natural antibodies. The persistent presence (even if only minor) of autoantibodies in healthy blood donors indicates an overlapping category of autoantibodies, which could become pathogenic, depending on the autoantibody characteristics such as avidity, epitope specificity, changes in the microenvironment leading to different oxidative status and others. This review uses the novel approach of studying the overall autoantibody population against APPs, their functions and connections to diseases. The primary function of autoantibodies against APPs (anti-APPs) is thought to promote their clearance, however autoantibodies against negative APPs have also been found and applying the same role to those is doubtful. There is also the theory of consumption in the stage of inflammation, which could be relevant to anti-APPs. Reports about protective roles of autoantibodies are also emerging, showing lowered levels of antibodies in diseases, which could be interesting for therapeutic intervention. PMID:21718807

  7. Impact of Mucosal Inflammation on Oral Simian Immunodeficiency Virus Transmission

    PubMed Central

    Chen, Hui-Ling; Hodara, Vida L.; Chu, Lianrui; Parodi, Laura M.; Smith, Lisa M.; Sexton, Valerie; Cappelli, David; Sodora, Donald L.

    2013-01-01

    Mucosal tissues are the primary route of transmission for most respiratory and sexually transmitted diseases, including human immunodeficiency virus (HIV). There is epidemiological evidence that genital mucosal inflammation leads to enhanced HIV type 1 (HIV-1) transmission. The objective of this study was to assess the influence of periodontal inflammation on oral HIV transmission using a nonhuman primate model of teeth ligature-induced periodontitis. Simian immunodeficiency virus (SIV) was nontraumatically applied to the gingiva after moderate gingivitis was identified through clinical and immunologic analyses (presence of inflammatory cytokines). Overall oral SIV infection rates were similar in the gingivitis-induced and control groups (5 infections following 12 SIV administrations for each), although more macaques were infected with multiple viral variants in the gingivitis group. SIV infection also affected the levels of antiviral and inflammatory cytokines in the gingival crevicular fluid, and a synergistic effect was observed, with alpha interferon and interferon-inducible protein 10 undergoing significant elevations following SIV infection in macaques with gingivitis compared to controls. These increases in antiviral and inflammatory immune modulators in the SIV-infected gingivitis macaques could also be observed in blood plasma, although the effects at both compartments were generally restricted to the acute phase of the infection. In conclusion, while moderate gingivitis was not associated with increased susceptibility to oral SIV infection, it resulted in elevated levels of cytokines in the oral mucosa and plasma of the SIV-infected macaques. These findings suggest a synergy between mucosal inflammation and SIV infection, creating an immune milieu that impacts the early stages of the SIV infection with potential implications for long-term pathogenesis. PMID:23175379

  8. The molecular mechanism of acute lung injury caused by Pseudomonas aeruginosa: from bacterial pathogenesis to host response.

    PubMed

    Sawa, Teiji

    2014-01-01

    Pseudomonas aeruginosa is the most common gram-negative pathogen causing pneumonia in immunocompromised patients. Acute lung injury induced by bacterial exoproducts is associated with a poor outcome in P. aeruginosa pneumonia. The major pathogenic toxins among the exoproducts of P. aeruginosa and the mechanism by which they cause acute lung injury have been investigated: exoenzyme S and co-regulated toxins were found to contribute to acute lung injury. P. aeruginosa secretes these toxins through the recently defined type III secretion system (TTSS), by which gram-negative bacteria directly translocate toxins into the cytosol of target eukaryotic cells. TTSS comprises the secretion apparatus (termed the injectisome), translocators, secreted toxins, and regulatory components. In the P. aeruginosa genome, a pathogenic gene cluster, the exoenzyme S regulon, encodes genes underlying the regulation, secretion, and translocation of TTSS. Four type III secretory toxins, namely ExoS, ExoT, ExoU, and ExoY, have been identified in P. aeruginosa. ExoS is a 49-kDa form of exoenzyme S, a bifunctional toxin that exerts ADP-ribosyltransferase and GTPase-activating protein (GAP) activity to disrupt endocytosis, the actin cytoskeleton, and cell proliferation. ExoT, a 53-kDa form of exoenzyme S with 75% sequence homology to ExoS, also exerts GAP activity to interfere with cell morphology and motility. ExoY is a nucleotidal cyclase that increases the intracellular levels of cyclic adenosine and guanosine monophosphates, resulting in edema formation. ExoU, which exhibits phospholipase A2 activity activated by host cell ubiquitination after translocation, is a major pathogenic cytotoxin that causes alveolar epithelial injury and macrophage necrosis. Approximately 20% of clinical isolates also secrete ExoU, a gene encoded within an insertional pathogenic gene cluster named P. aeruginosa pathogenicity island-2. The ExoU secretory phenotype is associated with a poor clinical outcome in P

  9. Histopathology and pathogenesis of caerulein-, duct ligation-, and arginine-induced acute pancreatitis in Sprague-Dawley rats and C57BL6 mice.

    PubMed

    Zhang, Jun; Rouse, Rodney L

    2014-09-01

    Three classical rodent models of acute pancreatitis were created in an effort to identify potential pre-clinical models of drug-induced pancreatitis (DIP) and candidate non-invasive biomarkers for improved detection of DIP. Study objectives included designing a lexicon to minimize bias by capturing normal variation and spontaneous and injury-induced changes while maintaining the ability to statistically differentiate degrees of change, defining morphologic anchors for novel pancreatic injury biomarkers, and improved understanding of mechanisms responsible for pancreatitis. Models were created in male Sprague-Dawley rats and C57BL6 mice through: 1) administration of the cholecystokinin analog, caerulein; 2) administration of arginine; 3) surgical ligation of the pancreatic duct. Nine morphologically detectable processes were used in the lexicon; acinar cell hypertrophy; acinar cell autophagy; acinar cell apoptosis; acinar cell necrosis; vascular injury; interstitial edema, inflammation and hemorrhage; fat necrosis; ductal changes; acinar cell atrophy. Criteria were defined for scoring levels (0 = absent, 1 = mild, 2 = moderate, 3 = severe) for each lexicon component. Consistent with previous studies, histopathology scores were significant greater in rats compared to mice at baseline and after treatment. The histopathology scores in caerulein and ligation-treated rats and mice were significantly greater than those of arginine-treated rats and mice. The present study supports a multifaceted pathogenesis for acute pancreatitis in which intra-acinar trypsinogen activation, damage to acinar cells, fat cells, and vascular cells as well as activation/degranulation of mast cells and activated macrophages all contribute to the initiation and/or progression of acute inflammation of the exocrine pancreas. PMID:24585404

  10. Phase 3 Trial of Domiciliary Humidification to Mitigate Acute Mucosal Toxicity During Radiation Therapy for Head-and-Neck Cancer: First Report of Trans Tasman Radiation Oncology Group (TROG) 07.03 RadioHUM Study

    SciTech Connect

    Macann, Andrew; Fua, Tsien; Milross, Chris G.; Porceddu, Sandro V.; Penniment, Michael; Wratten, Chris; Krawitz, Hedley; Poulsen, Michael; Tang, Colin I.; Morton, Randall P.; Hay, K. David; Thomson, Vicki; Bell, Melanie L.; King, Madeleine T.; Fraser-Browne, Carol L.; Hockey, Hans-Ulrich P.

    2014-03-01

    Purpose: To assess the impact of domicile-based humidification on symptom burden during radiation therapy (RT) for head-and-neck (H and N) cancer. Methods and Materials: From June 2007 through June 2011, 210 patients with H and N cancer receiving RT were randomized to either a control arm or to receive humidification using the Fisher and Paykel Healthcare MR880 humidifier. Humidification commenced on day 1 of RT and continued until Common Terminology Criteria for Adverse Events (CTCAE), version 3.0, clinical mucositis (CMuc) grade ≤1 occurred. Forty-three patients (42%) met a defined benchmark for humidification compliance and contributed to per protocol (PP) analysis. Acute toxicities, hospitalizations, and feeding tube events were recorded prospectively. The McMaster University Head and Neck Radiotherapy Questionnaire (HNRQ) was used for patient-reported outcomes. The primary endpoint was area under the curve (AUC) for CMuc grade ≥2. Results: There were no significant differences in AUC for CMuc ≥2 between the 2 arms. Humidification patients had significantly fewer days in hospital (P=.017). In compliant PP patients, the AUC for CTCAE functional mucositis score (FMuc) ≥2 was significantly reduced (P=.009), and the proportion who never required a feeding tube was significantly greater (P=.04). HNRQ PP analysis estimates also in the direction favoring humidification with less symptom severity, although differences at most time points did not reach significance. Conclusions: TROG 07.03 has provided efficacy signals consistent with a role for humidification in reducing symptom burden from mucositis, but the influence of humidification compliance on the results moderates recommendations regarding its practical utility.

  11. Mucosal dendritic cells shape mucosal immunity

    PubMed Central

    Chang, Sun-Young; Ko, Hyun-Jeong; Kweon, Mi-Na

    2014-01-01

    Dendritic cells (DCs) are key modulators that shape the immune system. In mucosal tissues, DCs act as surveillance systems to sense infection and also function as professional antigen-presenting cells that stimulate the differentiation of naive T and B cells. On the basis of their molecular expression, DCs can be divided into several subsets with unique functions. In this review, we focus on intestinal DC subsets and their function in bridging the innate signaling and adaptive immune systems to maintain the homeostasis of the intestinal immune environment. We also review the current strategies for manipulating mucosal DCs for the development of efficient mucosal vaccines to protect against infectious diseases. PMID:24626170

  12. Role of lysosomal enzymes released by alveolar macrophages in the pathogenesis of the acute phase of hypersensitivity pneumonitis

    PubMed Central

    Barrios, M. N.; Martín, T.; Sánchez, M. L.; Buitrago, J. M. González; Jiménez, A.

    1995-01-01

    Hydrolytic enzymes are the major constituents of alveolar macrophages (AM) and have been shown to be involved in many aspects of the inflammatory pulmonary response. The aim of this study was to evaluate the role of lysosomal enzymes in the acute phase of hypersensitivity pneumonitis (HPs). An experimental study on AM lysosomal enzymes of an HP-guinea-pig model was performed. The results obtained both in vivo and in vitro suggest that intracellular enzymatic activity decrease is, at least partly, due to release of lysosomal enzymes into the medium. A positive but slight correlation was found between extracellular lysosomal activity and four parameters of lung lesion (lung index, bronchoalveolar fluid total (BALF) protein concentration, BALF LDH and BALF alkaline phosphatase activities). All the above findings suggest that the AM release of lysosomal enzymes during HP is a factor involved, although possibly not the only one, in the pulmonary lesions appearing in this disease. PMID:18475615

  13. Pathogenesis of Hepatic Encephalopathy

    PubMed Central

    Ciećko-Michalska, Irena; Szczepanek, Małgorzata; Słowik, Agnieszka; Mach, Tomasz

    2012-01-01

    Hepatic encephalopathy can be a serious complication of acute liver failure and chronic liver diseases, predominantly liver cirrhosis. Hyperammonemia plays the most important role in the pathogenesis of hepatic encephalopathy. The brain-blood barrier disturbances, changes in neurotransmission, neuroinflammation, oxidative stress, GABA-ergic or benzodiazepine pathway abnormalities, manganese neurotoxicity, brain energetic disturbances, and brain blood flow abnormalities are considered to be involved in the development of hepatic encephalopathy. The influence of small intestine bacterial overgrowth (SIBO) on the induction of minimal hepatic encephalopathy is recently emphasized. The aim of this paper is to present the current views on the pathogenesis of hepatic encephalopathy. PMID:23316223

  14. Aberrant nuclear factor-kappa B activity in acute myeloid Leukemia: from molecular pathogenesis to therapeutic target

    PubMed Central

    Zhou, Jianbiao; Ching, Ying Qing; Chng, Wee-Joo

    2015-01-01

    The overall survival of patients with acute myeloid leukemia (AML) has not been improved significantly over the last decade. Molecularly targeted agents hold promise to change the therapeutic landscape in AML. The nuclear factor kappa B (NF-κB) controls a plethora of biological process through switching on and off its long list of target genes. In AML, constitutive NF-κB has been detected in 40% of cases and its aberrant activity enable leukemia cells to evade apoptosis and stimulate proliferation. These facts suggest that NF-κB signaling pathway plays a fundamental role in the development of AML and it represents an attractive target for the intervention of AML. This review summarizes our current knowledge of NF-κB signaling transduction including canonical and non-canonical NF-κB pathways. Then we specifically highlight what factors contribute to the aberrant activation of NF-κB activity in AML, followed by an overview of 8 important clinical trials of the first FDA approved proteasome inhibitor, Bortezomib (Velcade®), which is a NF-κB inhibitor too, in combination with other therapeutic agents in patients with AML. Finally, this review discusses the future directions of NF-κB inhibitor in treatment of AML, especially in targeting leukemia stem cells (LSCs). PMID:25823927

  15. Aberrant nuclear factor-kappa B activity in acute myeloid leukemia: from molecular pathogenesis to therapeutic target.

    PubMed

    Zhou, Jianbiao; Ching, Ying Qing; Chng, Wee-Joo

    2015-03-20

    The overall survival of patients with acute myeloid leukemia (AML) has not been improved significantly over the last decade. Molecularly targeted agents hold promise to change the therapeutic landscape in AML. The nuclear factor kappa B (NF-κB) controls a plethora of biological process through switching on and off its long list of target genes. In AML, constitutive NF-κB has been detected in 40% of cases and its aberrant activity enable leukemia cells to evade apoptosis and stimulate proliferation. These facts suggest that NF-κB signaling pathway plays a fundamental role in the development of AML and it represents an attractive target for the intervention of AML. This review summarizes our current knowledge of NF-κB signaling transduction including canonical and non-canonical NF-κB pathways. Then we specifically highlight what factors contribute to the aberrant activation of NF-κB activity in AML, followed by an overview of 8 important clinical trials of the first FDA approved proteasome inhibitor, Bortezomib (Velcade), which is a NF-κB inhibitor too, in combination with other therapeutic agents in patients with AML. Finally, this review discusses the future directions of NF-κB inhibitor in treatment of AML, especially in targeting leukemia stem cells (LSCs). PMID:25823927

  16. Mucosal Lesions in an Allergy Practice.

    PubMed

    Kohorst, John J; Bruce, Alison J; Torgerson, Rochelle R

    2016-04-01

    The diagnosis and treatment of mucosal disease with an allergic pathogenesis are challenging. Oral allergy is often a hypersensitivity reaction with variable symptoms and physical exam findings. Clinical diagnosis requires a history of prior allergen exposure, a delay from exposure to clinical findings, and improvement following allergen removal. The past decades have seen great contributions to the field of oral allergy. The aim of this review is to provide an approach to the diagnosis and treatment of oral dermatologic disease with a focus on diseases with an investigated allergic pathogenesis. PMID:26922434

  17. The pathogenesis of arthritis associated with acute hepatitis-B surface antigen-positive hepatitis. Complement activation and characterization of circulating immune complexes.

    PubMed Central

    Wands, J R; Mann, E; Alpert, E; Isselbacher, K J

    1975-01-01

    Circulating immune complexes were identified in cryoproteins isolated from serial samples of serum from six patients with acute viral hepatitis with and without arthritic symptoms. Cryoprecipitates were analyzed for the presence of hepatitis-B surface antigen (HBsAg) and hepatitis-B surface antibody (anti-HBs) by hemagglutination inhibition and hemagglutination. Complement components were detected by counter electrophoresis, and immunoglobulins were detected by gel diffusion. HBsAg, IgG, and IgM were identified in cryoprecipitates from all hepatitis patients, but were higher in concentration in patients with arthritis. Only cryoprecipitates from hepatitis patients with arthritis contained IgA and complement components C3, C4, and C5 as well as IgG and IgM, which disappear with resolution of the arthritis. The subtypes of IgG in these cryoprecipitates were predominantly the complement-fixing IgG1 and IgG3, HBsAg and anti-HBs were concentrated several-fold in the cryoprecipitates when compared to the serum concentration. Sequential studies in two patients demonstrated that the initial appearance of anti-HBs in the cryoprotein complex was associated with the detection in the complex of IgM suggesting a primary immune response to HBsAg. The C3 activator fragment (C3A) of the properdin complex was found in fresh serum obtained from three hepatitis patients with arthritis and not in uncomplicated hepatitis. The cryoprecipitable immune complexes from patients with arthritis converted C3PA in fresh normal sera to C3A in vitro whereas cryoprotein isolated from patients with uncomplicated hepatitis had no such effect. Thus, the transient appearance of circulating complement-fixing immune complexes in patients with the arthritis of acute hepatitis is associated with activation of both classical and alternate complement pathways and suggests that they play an important role in the pathogenesis of these serum sickness-like extrahepatic symptoms. Images PMID:1123429

  18. The PDZ-Binding Motif of Severe Acute Respiratory Syndrome Coronavirus Envelope Protein Is a Determinant of Viral Pathogenesis

    PubMed Central

    Jimenez-Guardeño, Jose M.; Nieto-Torres, Jose L.; DeDiego, Marta L.; Regla-Nava, Jose A.; Fernandez-Delgado, Raul; Castaño-Rodriguez, Carlos; Enjuanes, Luis

    2014-01-01

    A recombinant severe acute respiratory syndrome coronavirus (SARS-CoV) lacking the envelope (E) protein is attenuated in vivo. Here we report that E protein PDZ-binding motif (PBM), a domain involved in protein-protein interactions, is a major determinant of virulence. Elimination of SARS-CoV E protein PBM by using reverse genetics caused a reduction in the deleterious exacerbation of the immune response triggered during infection with the parental virus and virus attenuation. Cellular protein syntenin was identified to bind the E protein PBM during SARS-CoV infection by using three complementary strategies, yeast two-hybrid, reciprocal coimmunoprecipitation and confocal microscopy assays. Syntenin redistributed from the nucleus to the cell cytoplasm during infection with viruses containing the E protein PBM, activating p38 MAPK and leading to the overexpression of inflammatory cytokines. Silencing of syntenin using siRNAs led to a decrease in p38 MAPK activation in SARS-CoV infected cells, further reinforcing their functional relationship. Active p38 MAPK was reduced in lungs of mice infected with SARS-CoVs lacking E protein PBM as compared with the parental virus, leading to a decreased expression of inflammatory cytokines and to virus attenuation. Interestingly, administration of a p38 MAPK inhibitor led to an increase in mice survival after infection with SARS-CoV, confirming the relevance of this pathway in SARS-CoV virulence. Therefore, the E protein PBM is a virulence domain that activates immunopathology most likely by using syntenin as a mediator of p38 MAPK induced inflammation. PMID:25122212

  19. Involvement of leukotrienes in acute gastric damage.

    PubMed

    Boughton-Smith, N K

    1989-01-01

    The leukotrienes have potent inflammatory actions which could be of importance in gastric mucosal integrity. In animals, LTC4 produces vasoconstriction in the gastric mucosa. Furthermore, acute gastric damage produced by ethanol is accompanied by marked increases in the mucosal formation of LTC4 and LTB4. Depending on the extent of protection, prostaglandins either have no effect or prevent the increases in leukotriene formation which accompany ethanol-induced damage. Various non-specific inhibitors of leukotriene synthesis prevent ethanol and indomethacin-induced damage to the gastric mucosa. However, a novel selective 5-lipoxygenase inhibitor (BW A4C) had no effect on these models of acute gastric damage at doses which completely inhibited gastric mucosal leukotriene synthesis. These studies cast doubt on the role of the leukotrienes in these models of acute gastric damage. However, the potent biological actions of the leukotrienes may be of importance in the pathogenesis of other forms of gastric damage, or as mediators of chronic gastric ulceration or inflammation. PMID:2657289

  20. Pathogenesis of acute avian malaria. II. Anemia mediated by a cold-active autohemagglutinin from the blood of chickens with acute Plasmodium gallinaceum infection.

    PubMed

    Soni, J L; Cox, H W

    1975-03-01

    A cold-active hemagglutinin for trypsinized human type "O" erythrocytes (CAH) from blood of chickens with acute Plasmodium gallinaceum malaria was found to be associated with 19 S and 7 S globulin fractions of malarious chicken blood, but cleavage with 2-mercaptoethanol indicated that it was primarily of the IgM class of antibody. In serologic tests CAH reacted with trypsinized erythrocytes, and anti-chicken globulin. It did not react with other of the antigens or antibodies detected in the blood of malarious chickens. When the absorbed and eluted CAH was injected into normal chickens it produced an anaphylactic-like shock and caused a 25% reduction in red blood cell counts within 48 hours. Plasma samples collected during this interval showed signs of hemolysis. Reactions of blood cells from the recipient birds with fluorescein conjugated anti-chicken globulin indicated that CAH reacted with erythrocytes. The absence of fluorescent activity 3 days after injection suggested that these erythrocytes had been removed from the circulation. When normal chickens were injected with trypsinized autologous blood cells, CAH was detected within 3 days. The agglutination test again was active at temperatures below 22 degrees C and was negative when tested at 37 degrees C. In these birds the appearance of CAH was accompanied by reductions in red blood cell counts and by hemolysis. The results of these experiments suggest that CAH was not stimulated by plasmodial parasite antigen, but rather by autoantigens, which appear to be common to heterologous animal species, and which were in some manner expressed by the presence of the intracellular parasites, or by trypsin treatment. The experiments further suggest that this autohemagglutinin was partially causal of malarial anemia. The presence of other anemia factor(s) was indicated by anemia following injection of plasma that had been absorbed free of CAH. PMID:804265

  1. Why mucosal health?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aquaculture species depend more heavily on mucosal barriers than their terrestrial agricultural counterparts as they are continuously interacting with the aquatic microbiota. Unlike classical immune centers, such as the spleen and kidney, the accessibility of mucosal surfaces through immersion/dip t...

  2. Organ distribution of severe acute respiratory syndrome (SARS) associated coronavirus (SARS-CoV) in SARS patients: implications for pathogenesis and virus transmission pathways.

    PubMed

    Ding, Yanqing; He, Li; Zhang, Qingling; Huang, Zhongxi; Che, Xiaoyan; Hou, Jinlin; Wang, Huijun; Shen, Hong; Qiu, Liwen; Li, Zhuguo; Geng, Jian; Cai, Junjie; Han, Huixia; Li, Xin; Kang, Wei; Weng, Desheng; Liang, Ping; Jiang, Shibo

    2004-06-01

    We previously identified the major pathological changes in the respiratory and immune systems of patients who died of severe acute respiratory syndrome (SARS) but gained little information on the organ distribution of SARS-associated coronavirus (SARS-CoV). In the present study, we used a murine monoclonal antibody specific for SARS-CoV nucleoprotein, and probes specific for a SARS-CoV RNA polymerase gene fragment, for immunohistochemistry and in situ hybridization, respectively, to detect SARS-CoV systematically in tissues from patients who died of SARS. SARS-CoV was found in lung, trachea/bronchus, stomach, small intestine, distal convoluted renal tubule, sweat gland, parathyroid, pituitary, pancreas, adrenal gland, liver and cerebrum, but was not detected in oesophagus, spleen, lymph node, bone marrow, heart, aorta, cerebellum, thyroid, testis, ovary, uterus or muscle. These results suggest that, in addition to the respiratory system, the gastrointestinal tract and other organs with detectable SARS-CoV may also be targets of SARS-CoV infection. The pathological changes in these organs may be caused directly by the cytopathic effect mediated by local replication of the SARS-CoV; or indirectly as a result of systemic responses to respiratory failure or the harmful immune response induced by viral infection. In addition to viral spread through a respiratory route, SARS-CoV in the intestinal tract, kidney and sweat glands may be excreted via faeces, urine and sweat, thereby leading to virus transmission. This study provides important information for understanding the pathogenesis of SARS-CoV infection and sheds light on possible virus transmission pathways. This data will be useful for designing new strategies for prevention and treatment of SARS. PMID:15141376

  3. Endothelial microparticles carrying hedgehog-interacting protein induce continuous endothelial damage in the pathogenesis of acute graft-versus-host disease.

    PubMed

    Nie, Di-Min; Wu, Qiu-Ling; Zheng, Peng; Chen, Ping; Zhang, Ran; Li, Bei-Bei; Fang, Jun; Xia, Ling-Hui; Hong, Mei

    2016-05-15

    Accumulating evidence suggests that endothelial microparticles (EMPs), a marker of endothelial damage, are elevated in acute graft-versus-host disease (aGVHD), and that endothelial damage is implicated in the pathogenesis of aGVHD, but the mechanisms remain elusive. In this study, we detected the plasma EMP levels and endothelial damage in patients and mice with aGVHD in vivo and then examined the effects of EMPs derived from injured endothelial cells (ECs) on endothelial damage and the role of hedgehog-interacting protein (HHIP) carried by EMPs in these effects in vitro. Our results showed that EMPs were persistently increased in the early posttransplantation phase in patients and mice with aGVHD. Meanwhile, endothelial damage was continuous in aGVHD mice, but was temporary in non-aGVHD mice after transplantation. In vitro, EMPs induced endothelial damage, including increased EC apoptosis, enhanced reactive oxygen species, decreased nitric oxide production and impaired angiogenic activity. Enhanced expression of HHIP, an antagonist for the Sonic hedgehog (SHH) signaling pathway, was observed in patients and mice with aGVHD and EMPs from injured ECs. The endothelial damage induced by EMPs was reversed when the HHIP incorporated into EMPs was silenced with an HHIP small interfering RNA or inhibited with the SHH pathway agonist, Smoothened agonist. This work supports a feasible vicious cycle in which EMPs generated during endothelial injury, in turn, aggravate endothelial damage by carrying HHIP into target ECs, contributing to the continuously deteriorating endothelial damage in the development of aGVHD. EMPs harboring HHIP would represent a potential therapeutic target for aGVHD. PMID:27009877

  4. Gasoline-induced mucositis

    SciTech Connect

    Hoffman, D.L.; Swanson, B.Z. Jr.; Lutins, N.D.

    1980-02-01

    Gasoline-induced mucositis may become more common because of fuel shortages or increased fuel cost. Dentists should, therefore, consider this oral irritant in the differential diagnosis of oral lesions.

  5. Mucosal Health in Aquaculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Abstract The mucosal surfaces (skin, gill, and intestine) constitute the first line of defense against pathogen invasion while simultaneously carrying out a diverse array of other critical physiological processes, including nutrient absorption, osmoregulation, and waste excretion. Aquaculture specie...

  6. Nasal mucosal biopsy

    MedlinePlus

    Biopsy - nasal mucosa; Nose biopsy ... to fast for a few hours before the biopsy. ... Nasal mucosal biopsy is usually done when abnormal tissue is seen during examination of the nose. It may also be done ...

  7. Protective effects of Ankaferd blood stopper on aspirin-induced oxidative mucosal damage in a rat model of gastric injury.

    PubMed

    Hasgul, Rukiye; Uysal, Sema; Haltas, Hacer; Akyol, Sumeyye; Yuksel, Yasemin; Gurel, Ayse; Armutcu, Ferah

    2014-11-01

    The exposure of gastric mucosa to damaging factors, such as ethanol and some therapeutic drugs, produces pathological changes: inflammatory process, hemorrhagic erosions and even acute ulcers. Ankaferd blood stopper (ABS) comprises a standardized mixture of five different plant extracts. The purpose of our present investigations is to explain the participation of reactive oxygen species in acute gastric mucosal damage by acetylsalicylic acid (ASA) and the effects of new hemostatic agent ABS. Experiments were carried out on 23 male Wistar rats. To assess gastric mucosal damage, biochemical and histopathological data were used. The colorimetric assays were used to determine the malondialdehyde (MDA) and superoxide dismutase (SOD) activity. The level of myeloperoxidase (MPO) activity, the level of nitric oxide (NO) and the proinflammatory cytokine tumor necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent assay technique. We demonstrated that the biological effects of ROS were estimated by measuring the tissue and plasma levels of MDA, the products of lipid peroxidation, as well as the activity of SOD and the scavenger of ROS produced by ASA in the experiment group. Moreover, it was found that MPO activity as well as NO and TNF-α levels also demonstrated significant improvement by ABS treatment. The pathogenesis of experimental ASA-induced mucosal damage in rat stomach includes the generation of ROS that seems to play an important role, due to the generation of lipid peroxides, accompanied by the impairment of antioxidative enzyme activity of cells. ABS appeared to attenuate the oxidative and inflammatory changes caused by ASA-induced gastric mucosal damage in rats. PMID:23114375

  8. Mucosal delivery of vaccines.

    PubMed

    Del Giudice, G; Pizza, M; Rappuoli, R

    1999-09-01

    Oral delivery represents one of the most pursued approaches for large-scale human vaccination. Due to the different characteristics of mucosal immune response, as compared with systemic response, oral immunization requires particular methods of antigen preparation and selective strategies of adjuvanticity. In this paper, we describe the preparation and use of genetically detoxified bacterial toxins as mucosal adjuvants and envisage the possibility of their future exploitation for human oral vaccines. PMID:10525451

  9. Oral mucositis in myelosuppressive cancer therapy.

    PubMed

    Epstein, J B; Schubert, M M

    1999-09-01

    -inflammatory medications. These approaches to management have undergone initial study, but additional investigation is needed to determine their effectiveness with respect to the prevention of mucositis and symptom management and to determine appropriate doses and frequencies of intervention. Current studies and our increasing understanding of the pathogenesis of oral mucositis will lead to new approaches to management and improved quality of life for these patients. PMID:10503852

  10. Oral mucositis complicating chemotherapy and/or radiotherapy: options for prevention and treatment.

    PubMed

    Köstler, W J; Hejna, M; Wenzel, C; Zielinski, C C

    2001-01-01

    Chemotherapy- and radiotherapy-induced oral mucositis represents a therapeutic challenge frequently encountered in cancer patients. This side effect causes significant morbidity and may delay the treatment plan, as well as increase therapeutic expenses. The pathogenesis of this debilitating side effect can be attributed to the direct mucosal toxicity of cytotoxic agents and ionizing radiation and to indirect mucosal damage caused by a concomitant inflammatory reaction exacerbated in the presence of neutropenia, and the emergence of bacterial, mycotic, and viral infections. The prophylactic and therapeutic armamentarium for the treatment of oral mucositis consists of locally and systemically applied nonpharmacological measures and pharmacotherapeutics. PMID:11577493

  11. Pathogenesis of Candida vulvovaginitis.

    PubMed

    Sobel, J D

    1989-01-01

    The occurrence of candida vulvovaginitis (CVV) has been estimated based on statistical data from Great Britain to be an increase to 200/100,000 over 10 years to 1984. CVV in the US is the 2nd commonest cause of vaginal infection, with bacterial vaginosis occurring twice as often. 85-90% of the yeasts isolated from the vagina are candida albicans, based on biotyping rather that the newer methods of DNA hybridization. The pathogenesis of CVV is discussed in terms of the microbiology (virulence factors, adherence, germ tube and mycelium formation, proteinase secretion, and switching colonies), asymptomatic vaginal colonization, transformation to symptomatic vaginitis, host predisposing factors (pregnancy, oral contraceptives, diabetes mellitus, antimicrobes, and other), vaginal defense mechanisms (humoral system, phagocytic system, cell mediated immunity, vaginal flora, other), and pathogenesis of recurrent and chronic CVV (internal reservoir, sexual transmission, vaginal relapse, and experimental models) The discussion of the development of virulent symptoms is capsuled in the following comments. Vaginal cell receptivity varies among individuals, but all strains of C. Albicans adhere to both exfoliated vaginal and buccal epithelial cells, or mucosal surfaces, through the yeast surface mannoprotein. It is suggested from in vitro studies that germ tube and mycelium formation facilitates vaginal mucosal invasion. Exogenous and endogenous factors may enhance germination and precipitate symptomatic vaginitis, or inhibit germination. Increased proteinase secretion may be a result of the transformation from the blastoconidium/colonization phase to the germinated invasive vaginitis stage or an independent virulence factor. It is reported that hereditable spontaneous switching may occur spontaneously in vivo also. Colonizing yeasts with a change in environment can transform to a more virulent phase. Colonization rates vary from 10-25%, and the critical issue is understanding

  12. Radiation induced oral mucositis: a review of current literature on prevention and management.

    PubMed

    Mallick, Supriya; Benson, Rony; Rath, G K

    2016-09-01

    Oral mucositis (OM) is a major limiting acute side effect of radiotherapy for head and neck cancer. The spectrum of problems associated with mucositis includes oral pain, odynophagia, reduced oral intake, and secondary infections. Incidence of mucositis is increased with addition of concurrent chemotherapy as well as altered fractionation schedules. This leads to treatment interruption and suboptimal disease control. Hence, prevention as well as timely management of OM is necessary for optimum tumor control. We reviewed the English literature with key words "Radiation induced mucositis, Mucositis, Oral Mucositis" to find relevant articles describing incidence, pathophysiology, prophylaxis, and treatment of oral mucositis. Prevention and treatment of OM is an active area of research. Maintenance of oral hygiene is an important part in prevention of OM. A battery of agents including normal saline and alkali (soda bicarbonate) mouth washes, low level laser therapy, and benzydamine (non-steroidal analgesic and anti-inflammatory) have effectiveness in the prevention and treatment of radiation induced oral mucositis. Chlorhexidine mouth gargles are recommended for prevention of chemotherapy induced oral mucositis but is not recommended for radiotherapy associated mucositis. Treatment of co-existing infection is also important and both topical (povidone iodine) and systemic anti fungals should be used judiciously. Radiation induced oral mucositis is a common problem limiting the efficacy of radiation by increasing treatment breaks. Adequate prophylaxis and treatment may limit the severity of radiation mucositis and improve compliance to radiation which may translate in better disease control and survival. PMID:26116012

  13. Induction of apoptosis of lymphocytes in rat mucosal immune system

    PubMed Central

    Chen, Xue-Qing; Zhang, Wan-Dai; Song, Yu-Gang; Zhou, Dian-Yuan

    1998-01-01

    AIM: To undergo apoptosis during negative and positive selection processes in rat mucosal immune system which are implicated in the pathogenesis of various mucosal diseases. METHODS: Female Sprague-Dawley rats were given protein synthesis inhibitor, cycloheximide, intravenously or intraperitoneally, an apoptosis was recognized by morphological hallmark under light and electronmicroscopy, and the expression of proliferating cell nuclear antigen was visualized immunohistochemically. RESULTS: The apoptosis of mucosal lymphocytes in the digestive tract, as well as in trachea, uterus and lacrimal gland was induced by cycloheximide ( > 1.0 mg·kg-1 body weight), which were located mainly in lamina propria and germinal centers of lymphoid nodules. At the same time, a portion of crypt epithelial cells of proliferating zone in small and large intestine, and the epithelial cells in genital tract were also found to undergo apoptosis. Immunostainings showed that apoptotic cells expressed proliferating cell nuclear antigen. CONCLUSION: Apoptosis of lymphocytes in mucosal immune system can be induced by cycloheximide. This model will facilitate the understanding of normal mucosal immune system and its role in the pathogenesis of related diseases such as inflammatory bowel diseases. PMID:11819221

  14. Pathogenesis of rhinitis.

    PubMed

    Eifan, A O; Durham, S R

    2016-09-01

    Rhinitis is a heterogeneous condition that has been associated with inflammatory responses as in allergic rhinitis but can also occur in the absence of inflammation such as in so-called idiopathic (previously 'vasomotor') rhinitis. Allergic rhinitis affects approximately one in four of the population of westernized countries and is characterized by typical symptoms of nasal itching, sneezing, watery discharge and congestion. The intention of this review is to illustrate key concepts of the pathogenesis of rhinitis. Imbalance in innate and adaptive immunity together with environmental factors is likely to play major roles. In allergic rhinitis, initial allergen exposure and sensitization involves antigen-presenting cells, T and B lymphocytes and results in the generation of allergen-specific T cells and allergen-specific IgE antibodies. On re-exposure to relevant allergens, cross-linking of IgE on mast cells results in the release of mediators of hypersensitivity such as histamine and immediate nasal symptoms. Within hours, there is an infiltration by inflammatory cells, particularly Th2 T lymphocytes, eosinophils and basophils into nasal mucosal tissue that results in the late-phase allergic response. Evidence for nasal priming and whether or not remodelling may be a feature of allergic rhinitis will be reviewed. The occurrence of so-called local allergic rhinitis in the absence of systemic IgE will be discussed. Non-allergic (non-IgE-mediated) rhinitis will be considered in the context of inflammatory and non-inflammatory disorders. PMID:27434218

  15. Oral mucosal manifestations of autoimmune skin diseases.

    PubMed

    Mustafa, Mayson B; Porter, Stephen R; Smoller, Bruce R; Sitaru, Cassian

    2015-10-01

    A group of autoimmune diseases is characterised by autoantibodies against epithelial adhesion structures and/or tissue-tropic lymphocytes driving inflammatory processes resulting in specific pathology at the mucosal surfaces and the skin. The most frequent site of mucosal involvement in autoimmune diseases is the oral cavity. Broadly, these diseases include conditions affecting the cell-cell adhesion causing intra-epithelial blistering and those where autoantibodies or infiltration lymphocytes cause a loss of cell-matrix adhesion or interface inflammation. Clinically, patients present with blistering, erosions and ulcers that may affect the skin as well as further mucosal surfaces of the eyes, nose and genitalia. While the autoimmune disease may be suspected based on clinical manifestations, demonstration of tissue-bound and circulating autoantibodies, or lymphocytic infiltrates, by various methods including histological examination, direct and indirect immunofluorescence microscopy, immunoblotting and quantitative immunoassay is a prerequisite for definitive diagnosis. Given the frequency of oral involvement and the fact that oral mucosa is the initially affected site in many cases, the informed practitioner should be well acquainted with diagnostic and therapeutic aspects of autoimmune dermatosis with oral involvement. This paper reviews the pathogenesis and clinical presentation of these conditions in the oral cavity with a specific emphasis on their differential diagnosis and current management approaches. PMID:26117595

  16. Mucosal immunoregulation: transcription factors as possible therapeutic targets.

    PubMed

    Doganci, Aysefa; Neurath, Markus F; Finotto, Susetta

    2005-10-01

    Much progress has been recently made with regard to our understanding of the mucosal immune system in health and disease. In particular, it has been shown that uncontrolled mucosal immune responses driven by lymphocytes or non-lymphoid cells may lead to immunological diseases such as allergy, hypersensitivity and inflammation. Thus, a more detailed understanding of mucosal immune regulation and decision making at mucosal surfaces is essential for a better understanding of mucosal immune responses in health and disease. Antigen presenting cells and T lymphocytes play a key role in controlling mucosal immune responses. To deal with this key task, T helper cells differentiate into functionally distinct subsets: TH1 (CD4+ T Helper cells), TH2, TH3, Tr1, and CD4+CD25+ T (Treg) cells. This review summarizes the role of antigen presenting cells, eosinophils, mast cells and T-cell subsets in the pathogenesis of allergic inflammation and intestinal inflammation. Furthermore, we discuss novel immunological treatment modalities for allergic inflammation (e.g. allergic asthma) and chronic intestinal inflammation (e.g. inflammatory bowel diseases (IBD)) such as the control of the expression of transcription factors to redirect pathological immune responses. PMID:16248825

  17. Mucosal Immunology of HIV Infection

    PubMed Central

    Xu, Huanbin; Wang, Xiaolei; Veazey, Ronald S.

    2013-01-01

    Summary Recent advances in the immunology, pathogenesis, and prevention of human immunodeficiency virus (HIV) infection continue to reveal clues to the mechanisms involved in the progressive immunodeficiency attributed to infection but more importantly have shed light on the correlates of immunity to infection and disease progression. HIV selectively infects, eliminates, and/or dysregulates several key cells of the human immune system, thwarting multiple arms of the host immune response, and inflicting severe damage to mucosal barriers, resulting in tissue infiltration of ‘symbiotic’ intestinal bacteria and viruses that essentially become opportunistic infections promoting systemic immune activation. This leads to activation and recruitment or more target cells for perpetuating HIV infection, resulting in persistent, high level viral replication in lymphoid tissues, rapid evolution of resistant strains, and continued evasion of immune responses. However, vaccine studies and studies of spontaneous controllers are finally providing correlates of immunity from protection and disease progression, including virus-specific CD4+ T-cell responses, binding antibodies, innate immune responses, and generation of antibodies with potent antibody-dependent cell-mediated cytotoxicity activity. Emerging correlates of immunity indicate that prevention of HIV infection may be possible through effective vaccine strategies that protect and stimulate key regulatory cells and immune responses in susceptible hosts. Further, immune therapies specifically directed towards boosting specific aspects of the immune system may eventually lead to a cure for HIV-infected patients. PMID:23772612

  18. Anthrax Pathogenesis.

    PubMed

    Moayeri, Mahtab; Leppla, Stephen H; Vrentas, Catherine; Pomerantsev, Andrei P; Liu, Shihui

    2015-01-01

    Anthrax is caused by the spore-forming, gram-positive bacterium Bacillus anthracis. The bacterium's major virulence factors are (a) the anthrax toxins and (b) an antiphagocytic polyglutamic capsule. These are encoded by two large plasmids, the former by pXO1 and the latter by pXO2. The expression of both is controlled by the bicarbonate-responsive transcriptional regulator, AtxA. The anthrax toxins are three polypeptides-protective antigen (PA), lethal factor (LF), and edema factor (EF)-that come together in binary combinations to form lethal toxin and edema toxin. PA binds to cellular receptors to translocate LF (a protease) and EF (an adenylate cyclase) into cells. The toxins alter cell signaling pathways in the host to interfere with innate immune responses in early stages of infection and to induce vascular collapse at late stages. This review focuses on the role of anthrax toxins in pathogenesis. Other virulence determinants, as well as vaccines and therapeutics, are briefly discussed. PMID:26195305

  19. Temporal pathogenesis of experimental neonatal woodchuck hepatitis virus infection: increased initial viral load and decreased severity of acute hepatitis during the development of chronic viral infection.

    PubMed

    Cote, P J; Toshkov, I; Bellezza, C; Ascenzi, M; Roneker, C; Ann Graham, L; Baldwin, B H; Gaye, K; Nakamura, I; Korba, B E; Tennant, B C; Gerin, J L

    2000-10-01

    Acute hepatitis B virus (HBV) infections either resolve or progress to chronicity. Identification of early deviations in host-virus responses associated with these outcomes can further differentiate cause-effect mechanisms that initiate and maintain chronicity. Neonatal woodchucks were infected experimentally with the woodchuck hepatitis virus (WHV) at 3 days of age. At 8 or 14 weeks of age (i.e. , the early- or mid-acute stage of infection), whole blood and large surgical biopsies of the liver were obtained from infected animals and uninfected controls. These were stored for later correlating histopathologic responses and viral load with the subsequently determined outcome of infection. As of 1 year postinfection, half of the surgically treated infected woodchucks had developed self-limited infections, while the other half developed chronic infections. The self-limited outcome was characterized by decreased viral load in acute-phase liver and plasma and a generally robust acute hepatic inflammatory response. Comparisons at the same early time points revealed that the chronic outcome was characterized by increasing initial viral load in liver and plasma, and a detectable, but diminished, acute hepatic inflammation. These cotemporal comparisons indicate that there is an early host-response deviation during the acute phase of a developing chronic infection. Continued analysis of the tissues banked from this study will facilitate further temporal characterization of acute-phase mechanisms that determine resolution versus chronicity in WHV infection. Understanding such mechanisms may be useful in the rational design of therapy for established chronic HBV infection. PMID:11003627

  20. Gut Check: IFNγ Delays Mucosal Recovery during Antibiotic Therapy.

    PubMed

    Chung, Lawton K; Bliska, James B

    2016-08-10

    Antibiotic therapy has been largely ineffective in improving clinical outcomes following Salmonellosis, yet the reasons why remain obscure. In this issue of Cell Host & Microbe, Dolowschiak et al. (2016) report that IFNγ produced by NK and T cells following antibiotic treatment of acute Salmonella infection limits mucosal remission. PMID:27512899

  1. Prevention and treatment of oropharyngeal mucositis following cancer therapy: are there new approaches?

    PubMed

    Kwong, Karis K F

    2004-01-01

    Oropharyngeal mucositis is an acute and distressing toxic effect of chemotherapy and head and neck irradiation. This oral sequela significantly impairs the daily functioning and quality of life of patients. The biological basis of mucositis is quite complex, involving sequential interaction of chemotherapeutic drugs or irradiation on mitosis of proliferating epithelium, a number of cytokines, and elements of oral microbial environment. Various interventions based on biological attenuation have been tested for mucositis. Such interventions have been reviewed elsewhere; however, most reviews focus on biomedical outcomes. Little attention has been paid to mucositis outcomes with oral morbidity or psychosocial aspects. The purpose of this article is to review the current research studies on the prevention and treatment of oropharyngeal mucositis following chemotherapy, radiotherapy, and bone marrow transplantation with an emphasis on biomedical, oral symptomatic, and functional impairment outcomes. In addition, further avenues of mucositis management, including psychotherapeutic intervention and integrated and stage-based treatment approaches are discussed. PMID:15238805

  2. Topical cocaine for relief of mucosal pain.

    PubMed

    Newport, Kristina; Coyne, Patrick

    2010-06-01

    Painful mucosal lesions negatively affect quality of life. When located in the oral cavity, they can cause pain that interferes with speech and swallowing. Acute pain from intra-oral lesions is difficult to treat with conventional methods such as systemic opioids or viscous lidocaine. These cases exemplify a safe, fast and effective method for treating painful mouth lesions that are not responsive to standard treatments. Mr. D and Mr. G had from painful oral lesions caused by squamous cell carcinoma. Severe pain interfered with their ability to speak and swallow, resulting in poor nutrition and dehydration. 4% liquid cocaine, self-applied topically to the open mouth sores, resulted in relief within minutes in both cases. Repeated dosing every six hours allowed both patients to restart oral nutrition without any reported side effects. Topical cocaine has not been described for repeated dosing for oral or other mucosal pain. Potential side effects of mucosal administration include gingival recession and erythematous lesions. If the recommended topical doses are exceeded, liquid cocaine may be absorbed systemically causing a stimulant response or addiction. When used appropriately, however, this intervention can result in a dramatic improvement in quality of life and functional status. PMID:20504138

  3. Collaborative studies in mucosal immunology in Goroka.

    PubMed

    Clancy, Robert

    2010-01-01

    A collaborative program between the Papua New Guinea (PNG) Institute of Medical Research and the Hunter Mucosal Group has completed studies relevant to protection of the airways against bacterial infection. Specifically, these studies addressed the mucosal capacity to produce local immunoglobulins and the capacity of the airways to respond to an oral vaccine containing inactivated nontypeable Haemophilus influenzae (NTHi). The mucosal IgA response to NTHi antigens was blunted in both children and adults in PNG compared with that found in Australian children and adults, whose airways are colonized only intermittently. Despite this, when oral NTHi is given to Papua New Guinean adults with chronic airways disease, it is followed by a significant (50%) reduction in incidence of acute bronchitic episodes, and a 3-log reduction in density of colonization, which persisted about 10 months. The implications of these key findings are discussed with respect to both mechanism and wider control of pathology emanating from abnormal airways colonization in a PNG environment. PMID:23163182

  4. C-Reactive Protein Levels and Radiation-Induced Mucositis in Patients With Head-and-Neck Cancer

    SciTech Connect

    Ki, Yongkan; Kim, Wontaek Nam, Jiho; Kim, Donghyun; Park, Dahl; Kim, Dongwon

    2009-10-01

    Purpose: To evaluate the relationship between C-reactive protein (CRP) levels or the erythrocyte sedimentation rate (ESR) and the grade of acute radiation-induced mucositis in patients with head-and-neck cancer. Methods and Materials: This study was performed in 40 patients who received intensity-modulated radiation therapy as a radical treatment of primary laryngo-pharyngeal cancer. Serum CRP level and ESR were initially checked on the day of radiotherapy simulation and were measured every week during the irradiation schedule and two times biweekly after radiotherapy. Mucosal reactions were evaluated by radiation oncologists on days of blood sampling. Results: The distribution of the most severe mucositis was Grade I mucositis in 10% of the patients, Grade II in 60% of the patients and Grade III in 30% of the patients. Statistical analysis indicated a significant rise in the CRP level (p < 0.001) according to radiation fraction number and grade of mucositis. A change of the mean CRP level was correlated with progression of mean grade of mucositis according to fraction number. The ESR did not show any statistically significant relationship with radiotherapy fraction number and grade of acute mucositis. Conclusions: There was a significant correlation between the presence of acute mucositis and CRP level in this study. The CRP level could be conveniently determined along with evaluation of mucosal reactions during or after radiotherapy to provide further information on radiation-induced mucositis.

  5. Poxvirus pathogenesis.

    PubMed Central

    Buller, R M; Palumbo, G J

    1991-01-01

    Poxviruses are a highly successful family of pathogens, with variola virus, the causative agent of smallpox, being the most notable member. Poxviruses are unique among animal viruses in several respects. First, owing to the cytoplasmic site of virus replication, the virus encodes many enzymes required either for macromolecular precursor pool regulation or for biosynthetic processes. Second, these viruses have a very complex morphogenesis, which involves the de novo synthesis of virus-specific membranes and inclusion bodies. Third, and perhaps most surprising of all, the genomes of these viruses encode many proteins which interact with host processes at both the cellular and systemic levels. For example, a viral homolog of epidermal growth factor is active in vaccinia virus infections of cultured cells, rabbits, and mice. At least five virus proteins with homology to the serine protease inhibitor family have been identified and one, a 38-kDa protein encoded by cowpox virus, is thought to block a host pathway for generating a chemotactic substance. Finally, a protein which has homology with complement components interferes with the activation of the classical complement pathway. Poxviruses infect their hosts by all possible routes: through the skin by mechanical means (e.g., molluscum contagiosum infections of humans), via the respiratory tract (e.g., variola virus infections of humans), or by the oral route (e.g., ectromelia virus infection of the mouse). Poxvirus infections, in general, are acute, with no strong evidence for latent, persistent, or chronic infections. They can be localized or systemic. Ectromelia virus infection of the laboratory mouse can be systemic but inapparent with no mortality and little morbidity, or highly lethal with death in 10 days. On the other hand, molluscum contagiosum virus replicates only in the stratum spinosum of the human epidermis, with little or no involvement of the dermis, and does not spread systemically from the site of

  6. Hydrophobicity of mucosal surface and its relationship to gut barrier function.

    PubMed

    Qin, Xiaofa; Caputo, Francis J; Xu, Da-Zhong; Deitch, Edwin A

    2008-03-01

    Loss of the gut barrier has been implicated in the pathogenesis of the multiple organ dysfunction syndrome, and, thus, understanding the intestinal barrier is of potential clinical importance. An important, but relatively neglected, component of the gut barrier is the unstirred mucus layer, which through its hydrophobic and other properties serves as an important barrier to bacterial and other factors within the gut lumen. Thus, the goal of this study was to establish a reproducible method of measuring mucosal hydrophobicity and test the hypothesis that conditions that decrease mucosal hydrophobicity are associated with increased gut permeability. Hydrophobicity was measured in various segments of normal gut by measuring the contact angle of an aqueous droplet placed on the mucosal surface using a commercial goniometer. Second, the effect of the mucolytic agent N-acetyl cysteine on mucosal hydrophobicity and gut permeability was measured, as was the effects of increasing periods of in vivo gut ischemia on these parameters. Gut ischemia was induced by superior mesenteric artery occlusion, and gut permeability was measured by the mucosal-to-serosal passage of fluoresceine isothiocyanate-dextran (4.3 kDa) (FD4) across the everted sacs of ileum. Intestinal mucosal hydrophobicity showed a gradual increase from the duodenum to the end of the ileum and remained at high level in the cecum, colon, and rectum. Both N-acetyl cysteine treatment and ischemia caused a dose-dependent decrease in mucosal hydrophobicity, which significantly correlated increased gut permeability. Mucosal hydrophobicity of the intestine can be reproducibly measured, and decreases in mucosal hydrophobicity closely correlate with increased gut permeability. These results suggest that mucosal hydrophobicity can be a reliable method of measuring the barrier function of the unstirred mucus layer and a useful parameter in evaluating the pathogenesis of gut barrier dysfunction. PMID:17693944

  7. Head and neck mucosal melanoma: a review.

    PubMed

    Lourenço, Silvia V; Fernandes, Juliana D; Hsieh, Ricardo; Coutinho-Camillo, Claudia M; Bologna, Sheyla; Sangueza, Martin; Nico, Marcello M S

    2014-07-01

    Head and neck mucosal melanoma (MM) is an aggressive and rare neoplasm of melanocytic origin. To date, few retrospective series and case reports have been reported on MM. This article reviews the current evidence on head and neck MM and the molecular pathways that mediate the pathogenesis of this disease. Head and neck MM accounts for 0.7%-3.8% of all melanomas and involve (in decreasing order of frequency) the sinonasal cavity, oral cavity, pharynx, larynx, and upper esophagus. Although many studies have examined MM of the head and neck and the underlying molecular pathways, individual genetic and molecular alterations were less investigated. Further studies are needed to complement existing data and to increase our understanding of melanocytes tumorigenesis. PMID:24423929

  8. Renal Distribution Volumes of Indocyanine Green, [51Cr]EDTA, and 24Na in Man during Acute Renal Failure after Shock. IMPLICATIONS FOR THE PATHOGENESIS OF ANURIA

    PubMed Central

    Reubi, F. C.; Vorburger, C.; Tuckman, J.

    1973-01-01

    The mechanism responsible for the anuria in acute renal failure after shock is still controversial. Suppressed glomerular filtration and/or tubular back-diffusion of the filtrate are major possible causes. In the present investigation, seven patients with acute anuria, three of these seven again in the polyuric phase, six patients with moderate renal impairment, four patients with chronic renal failure, and eight subjects with normal renal function were studied by a multiple indicator-dilution method in which the total renal blood flow and renal distribution volumes of indocyanine green, [51Cr]EDTA, and 24Na were determined. In normal subjects the average values for one kidney were 582 ml/min, 42 ml, 92 ml, and 139 ml, respectively. The measurements in the patients with moderate renal impairment were similar to those in the normal subjects, but were decreased in chronic renal failure. In acute anuria, the average values were 269 ml/min, 40 ml, 101 ml, and 114 ml and the kidney volume, estimated radiographically, was increased by 40%. When expressed as milliliters per milliliters kidney, the average distribution volume of 24Na was decreased from 0.64 to 0.38. This decrease is consistent with the hypothesis that suppressed filtration is largely responsible for the anuria and that back-diffusion is, at most, a contributory factor. The apparent contradiction between the relatively well-preserved total blood flow and the suppressed filtration may be due to a combination of afferent vasoconstriction and efferent vasodilatation. This view is supported by the observation that low filtration fractions were found in clearance measurements performed during the polyuric phase. PMID:4630601

  9. Mucosal biofilms of Candida albicans.

    PubMed

    Ganguly, Shantanu; Mitchell, Aaron P

    2011-08-01

    Biofilms are microbial communities that form on surfaces and are embedded in an extracellular matrix. C. albicans forms pathogenic mucosal biofilms that are evoked by changes in host immunity or mucosal ecology. Mucosal surfaces are inhabited by many microbial species; hence these biofilms are polymicrobial. Several recent studies have applied paradigms of biofilm analysis to study mucosal C. albicans infections. These studies reveal that the Bcr1 transcription factor is a master regulator of C. albicans biofilm formation under diverse conditions, though the most relevant Bcr1 target genes can vary with the biofilm niche. An important determinant of mucosal biofilm formation is the interaction with host defenses. Finally, studies of interactions between bacterial species and C. albicans provide insight into the communication mechanisms that endow polymicrobial biofilms with unique properties. PMID:21741878

  10. Experience with registered mucosal vaccines.

    PubMed

    Dietrich, Guido; Griot-Wenk, Monika; Metcalfe, Ian C; Lang, Alois B; Viret, Jean-François

    2003-01-30

    Most pathogens gain access to their host through mucosal surfaces. It is therefore desirable to develop vaccination strategies that lead to mucosal immune responses. Ideally, a vaccine should be administered mucosally in order to elicit mucosal protection. Several attenuated live viral and bacterial pathogens are registered as oral vaccines for human use, including the oral polio vaccine (Sabin) as well as attenuated strains of Salmonella typhi and Vibrio cholerae. These attenuated bacterial live vaccines-S. typhi Ty21a as well as V. cholerae CVD 103-HgR-are employed as vaccines against typhoid and cholera, respectively. In this manuscript, we review the immune responses that are induced by these vaccines, with a focus on mucosal immunity. PMID:12531339

  11. The Role of Intestinal Microbiota in the Development and Severity of Chemotherapy-Induced Mucositis

    PubMed Central

    van Vliet, Michel J.; Harmsen, Hermie J. M.; de Bont, Eveline S. J. M.; Tissing, Wim J. E.

    2010-01-01

    Mucositis, also referred to as mucosal barrier injury, is one of the most debilitating side effects of radiotherapy and chemotherapy treatment. Clinically, mucositis is associated with pain, bacteremia, and malnutrition. Furthermore, mucositis is a frequent reason to postpone chemotherapy treatment, ultimately leading towards a higher mortality in cancer patients. According to the model introduced by Sonis, both inflammation and apoptosis of the mucosal barrier result in its discontinuity, thereby promoting bacterial translocation. According to this five-phase model, the intestinal microbiota plays no role in the pathophysiology of mucositis. However, research has implicated a prominent role for the commensal intestinal microbiota in the development of several inflammatory diseases like inflammatory bowel disease, pouchitis, and radiotherapy-induced diarrhea. Furthermore, chemotherapeutics have a detrimental effect on the intestinal microbial composition (strongly decreasing the numbers of anaerobic bacteria), coinciding in time with the development of chemotherapy-induced mucositis. We hypothesize that the commensal intestinal microbiota might play a pivotal role in chemotherapy-induced mucositis. In this review, we propose and discuss five pathways in the development of mucositis that are potentially influenced by the commensal intestinal microbiota: 1) the inflammatory process and oxidative stress, 2) intestinal permeability, 3) the composition of the mucus layer, 4) the resistance to harmful stimuli and epithelial repair mechanisms, and 5) the activation and release of immune effector molecules. Via these pathways, the commensal intestinal microbiota might influence all phases in the Sonis model of the pathogenesis of mucositis. Further research is needed to show the clinical relevance of restoring dysbiosis, thereby possibly decreasing the degree of intestinal mucositis. PMID:20523891

  12. Reverse Genetics for Fusogenic Bat-Borne Orthoreovirus Associated with Acute Respiratory Tract Infections in Humans: Role of Outer Capsid Protein σC in Viral Replication and Pathogenesis

    PubMed Central

    Kawagishi, Takahiro; Kanai, Yuta; Tani, Hideki; Shimojima, Masayuki; Saijo, Masayuki; Matsuura, Yoshiharu; Kobayashi, Takeshi

    2016-01-01

    Nelson Bay orthoreoviruses (NBVs) are members of the fusogenic orthoreoviruses and possess 10-segmented double-stranded RNA genomes. NBV was first isolated from a fruit bat in Australia more than 40 years ago, but it was not associated with any disease. However, several NBV strains have been recently identified as causative agents for respiratory tract infections in humans. Isolation of these pathogenic bat reoviruses from patients suggests that NBVs have evolved to propagate in humans in the form of zoonosis. To date, no strategy has been developed to rescue infectious viruses from cloned cDNA for any member of the fusogenic orthoreoviruses. In this study, we report the development of a plasmid-based reverse genetics system free of helper viruses and independent of any selection for NBV isolated from humans with acute respiratory infection. cDNAs corresponding to each of the 10 full-length RNA gene segments of NBV were cotransfected into culture cells expressing T7 RNA polymerase, and viable NBV was isolated using a plaque assay. The growth kinetics and cell-to-cell fusion activity of recombinant strains, rescued using the reverse genetics system, were indistinguishable from those of native strains. We used the reverse genetics system to generate viruses deficient in the cell attachment protein σC to define the biological function of this protein in the viral life cycle. Our results with σC-deficient viruses demonstrated that σC is dispensable for cell attachment in several cell lines, including murine fibroblast L929 cells but not in human lung epithelial A549 cells, and plays a critical role in viral pathogenesis. We also used the system to rescue a virus that expresses a yellow fluorescent protein. The reverse genetics system developed in this study can be applied to study the propagation and pathogenesis of pathogenic NBVs and in the generation of recombinant NBVs for future vaccines and therapeutics. PMID:26901882

  13. Pathogenesis of nasal polyps: an update.

    PubMed

    Pawliczak, Rafal; Lewandowska-Polak, Anna; Kowalski, Marek L

    2005-11-01

    The cause of nasal polyp formation is still unknown. Genetic predisposition has been suggested, but there are scanty data to support such theories. Activated epithelial cells may be the major source of mediators inducing influx of inflammatory cells (mostly eosinophils) and proliferation and activation of fibroblasts leading to nasal polyp formation. Infectious agents (including viruses, bacteria, or fungi) may be potential primary factors activating nasal epithelial cells. Proinflammatory cytokines and growth factors play important roles in the persistence of mucosal inflammation associated with nasal polyps. Arachidonic acid metabolites seem to be particularly important in the pathogenesis of nasal polyps in patients with aspirin hypersensitivity rhinosinusitis/asthma syndrome. PMID:16216171

  14. Pathogenesis of arenavirus hemorrhagic fevers.

    PubMed

    Moraz, Marie-Laurence; Kunz, Stefan

    2011-01-01

    Viral hemorrhagic fevers (VHFs) caused by arenaviruses belong to the most devastating emerging human diseases and represent serious public health problems. Arenavirus VHFs in humans are acute diseases characterized by fever and, in severe cases, different degrees of hemorrhages associated with a shock syndrome in the terminal stage. Over the past years, much has been learned about the pathogenesis of arenaviruses at the cellular level, in particular their ability to subvert the host cell's innate antiviral defenses. Clinical studies and novel animal models have provided important new information about the interaction of hemorrhagic arenaviruses with the host's adaptive immune system, in particular virus-induced immunosuppression, and have provided the first hints towards an understanding of the terminal hemorrhagic shock syndrome. The scope of this article is to review our current knowledge on arenavirus VHF pathogenesis with an emphasis on recent developments. PMID:21171877

  15. Alteration of the Redox State with Reactive Oxygen Species for 5-Fluorouracil-Induced Oral Mucositis in Hamsters

    PubMed Central

    Wada-Takahashi, Satoko; Takahashi, Shun-suke; Lee, Masaichi Chang-il

    2013-01-01

    Oral mucositis is often induced in patients receiving cancer chemotherapy treatment. It has been reported that oral mucositis can reduce quality of life, as well as increasing the incidence of mortality. The participation of reactive oxygen species (ROS) in the pathogenesis of oral mucositis is well known, but no report has actually demonstrated the presence of ROS. Thus, the purpose of this study was thus to demonstrate the involvement of ROS and the alteration of the redox state in oral mucositis using an in vivo L-band electron spin resonance (ESR) technique. An oral mucositis animal model induced by treatment of 5-fluorouracil with 10% acetic acid in hamster cheek pouch was used. Lipid peroxidation was measured as the level of malondialdehyde determined by the thiobarbituric acid reaction. The rate constants of the signal decay of nitroxyl compounds using in vivo L-band ESR were calculated from the signal decay curves. Firstly, we established the oral mucositis animal model induced by treatment of 5-fluorouracil with acetic acid in hamster cheek pouch. An increased level of lipid peroxidation in oral mucositis was found by measuring malondialdehyde using isolated hamster cheek pouch ulcer. In addition, as a result of in vivo L-band ESR measurements using our model animals, the decay rate constants of carbamoyl-PROXYL, which is a reagent for detecting the redox balance in tissue, were decreased. These results suggest that a redox imbalance might occur by excessive generation of ROS at an early stage of oral mucositis and the consumption of large quantities of antioxidants including glutathione in the locality of oral mucositis. These findings support the presence of ROS involved in the pathogenesis of oral mucositis with anti-cancer therapy, and is useful for the development of novel therapies drugs for oral mucositis. PMID:24376587

  16. Novel insights into phosgene-induced acute lung injury in rats: role of dysregulated cardiopulmonary reflexes and nitric oxide in lung edema pathogenesis.

    PubMed

    Li, Wenli; Liu, Fangfang; Wang, Chen; Truebel, Hubert; Pauluhn, Juergen

    2013-02-01

    Phosgene gas is a lower respiratory tract irritant. As such, it stimulates nociceptive vagal C-fiber-related reflexes in a dose-rate and concentration × exposure duration (C × t)-dependent manner. In rats, this reflex is characterized by extended apnea time periods, bradycardia, and hypothermia. Although inhalation exposures at nonlethal C × t products show rapid reversibility of reflexively induced changes in respiratory patterns, lethal C × t products seem to cause prolonged stimulation after discontinued exposure to phosgene. This observation has been taken as indirect evidence that phosgene-induced lethal lung edema is likely to be associated with a dysfunctional neurogenic control of cardiopulmonary and microvascular physiology. In order to verify this hypothesis, data from respiratory function measurements during and after the inhalation exposure to phosgene gas were compared with time-course measurements of cardiac function over 20 h post-phosgene exposure. These data were complemented by time-course analyses of nitric oxide (NO(e)) and carbon dioxide in exhaled breath, including time-dependent changes of extravasated protein in bronchoalveolar lavage fluid and hemoglobin in blood. The nitric oxidase synthetase inhibitors L-NAME and L-NIL were used to further elucidate the role of NO(e) in this type of acute lung injury and whether its analysis can serve as an early biomarker of pulmonary injury. Collectively, the sequence and time course of pathological events in phosgene-induced lung edema appear to suggest that overstimulated, continued sensorimotor vagal reflexes affect cardiopulmonary hemodynamics. A continued parasympathetic tone appears to be involved in this etiopathology. PMID:23143928

  17. Molecular Pathogenesis of Post-Transplant Acute Kidney Injury: Assessment of Whole-Genome mRNA and MiRNA Profiles

    PubMed Central

    Wilflingseder, Julia; Sunzenauer, Judith; Toronyi, Eva; Heinzel, Andreas; Kainz, Alexander; Mayer, Bernd; Perco, Paul; Telkes, Gábor; Langer, Robert M.; Oberbauer, Rainer

    2014-01-01

    Acute kidney injury (AKI) affects roughly 25% of all recipients of deceased donor organs. The prevention of post-transplant AKI is still an unmet clinical need. We prospectively collected zero-hour, indication as well as protocol kidney biopsies from 166 allografts between 2011 and 2013. In this cohort eight cases with AKI and ten matched allografts without pathology serving as control group were identified with a follow-up biopsy within the first twelve days after engraftment. For this set the zero-hour and follow-up biopsies were subjected to genome wide microRNA and mRNA profiling and analysis, followed by validation in independent expression profiles of 42 AKI and 21 protocol biopsies for strictly controlling the false discovery rate. Follow-up biopsies of AKI allografts compared to time-matched protocol biopsies, further baseline adjustment for zero-hour biopsy expression level and validation in independent datasets, revealed a molecular AKI signature holding 20 mRNAs and two miRNAs (miR-182-5p and miR-21-3p). Next to several established biomarkers such as lipocalin-2 also novel candidates of interest were identified in the signature. In further experimental evaluation the elevated transcript expression level of the secretory leukocyte peptidase inhibitor (SLPI) in AKI allografts was confirmed in plasma and urine on the protein level (p<0.001 and p = 0.003, respectively). miR-182-5p was identified as a molecular regulator of post-transplant AKI, strongly correlated with global gene expression changes during AKI. In summary, we identified an AKI-specific molecular signature providing the ground for novel biomarkers and target candidates such as SLPI and miR-182-5p in addressing AKI. PMID:25093671

  18. Pathogenesis of Alcoholic Liver Disease.

    PubMed

    Dunn, Winston; Shah, Vijay H

    2016-08-01

    Alcoholic liver disease includes a broad clinical-histological spectrum from simple steatosis, cirrhosis, acute alcoholic hepatitis with or without cirrhosis to hepatocellular carcinoma as a complication of cirrhosis. The pathogenesis of alcoholic liver disease can be conceptually divided into (1) ethanol-mediated liver injury, (2) inflammatory immune response to injury, (3) intestinal permeability and microbiome changes. Corticosteroids may improve outcomes, but this is controversial and probably only impacts short-term survival. New pathophysiology-based therapies are under study, including antibiotics, caspase inhibition, interleukin-22, anakinra, FXR agonist and others. These studies provide hope for better future outcomes for this difficult disease. PMID:27373608

  19. Pathogenesis of Aleutian mink disease parvovirus infection: effects of suppression of antibody response on viral mRNA levels and on development of acute disease.

    PubMed Central

    Alexandersen, S; Storgaard, T; Kamstrup, N; Aasted, B; Porter, D D

    1994-01-01

    We suppressed the B-cell development and antibody response in mink by using treatment with polyclonal anti-immunoglobulin M (anti-IgM) to study the effects of antiviral antibodies on development of Aleutian mink disease parvovirus (ADV)-induced disease in more detail. Newborn mink kits were injected intraperitoneally with 1 mg of either anti-IgM or a control preparation three times a week for 30 to 34 days. At 21 days after birth, groups of mink kits were infected with the highly virulent United isolate of ADV. At selected time points, i.e., postinfection days 9, 13, 29, and 200, randomly chosen mink kits were sacrificed, and blood and tissues were collected for analyses. The efficacy of immunosuppressive treatment was monitored by electrophoretic techniques and flow cytometry. Effects of treatment on viral replication, on viral mRNA levels, and on development of acute or chronic disease were determined by histopathological, immunoelectrophoretic, and molecular hybridization techniques. Several interesting findings emerged from these studies. First, antiviral antibodies decreased ADV mRNA levels more than DNA replication. Second, suppression of B-cell development and antibody response in mink kits infected at 21 days of age resulted in production of viral inclusion bodies in alveolar type II cells. Some of these kits showed mild clinical signs of respiratory disease, and one kit died of respiratory distress; however, clinical signs were seen only after release of immunosuppression, suggesting that the production of antiviral antibodies, in combination with the massive amounts of free viral antigen present, somehow is involved in the induction of respiratory distress. It is suggested that the antiviral antibody response observed in mink older than approximately 14 days primarily, by a yet unknown mechanism, decreases ADV mRNA levels which, if severe enough, results in restricted levels of DNA replication and virion production. Furthermore, such a restricted ADV

  20. Microbiome and mucosal inflammation as extra-articular triggers for rheumatoid arthritis and autoimmunity

    PubMed Central

    Brusca, Samuel B; Abramson, Steven B; Scher, Jose U

    2014-01-01

    Purpose of Review Despite progress towards understanding the molecular pathogenesis of Rheumatoid Arthritis (RA), its etiology remains elusive. Genes are important but rather insufficient to explain the majority of RA cases. This review describes novel data supporting the microbiome and its interactions with the human host as potential en(‘in’)vironmental factors in RA pathogenesis. Recent Findings Animal models of inflammatory arthritis have shown that the presence of bacteria in mucosal surfaces is sufficient to alter local and systemic host immune responses and elicit joint inflammation. Human RA studies have focused on three mucosal sites: the gut, the gingival, and the respiratory tree. The oral microbiome, and specifically Porphyromonas gingivalis (P. gingivalis), has long been implicated. Novel sequencing technologies have allowed investigations into the role of the gut microbiome in the development of autoimmune arthritis. Most recently, the pulmonary parenchyma has also been described as yet another possible mucosal site of initiation of autoimmunity in RA. Summary Emerging data implicates the microbiome in RA pathogenesis. Mucosal sites exposed to a high load of bacterial antigens - such as the periodontium, lung, and gut - may represent the initial site of autoimmune generation. If validated, these findings could lead to the discovery of potential biomarkers and therapeutic approaches in the pre-clinical and clinical phases of RA. PMID:24247114

  1. Mucosal leishmaniasis: an underestimated presentation of a neglected disease.

    PubMed

    Strazzulla, Alessio; Cocuzza, Salvatore; Pinzone, Marilia Rita; Postorino, Maria Concetta; Cosentino, Stefano; Serra, Agostino; Cacopardo, Bruno; Nunnari, Giuseppe

    2013-01-01

    We present a review of current knowledge about mucosal leishmaniasis (ML). Although involvement of mucous membranes is classically admitted in New World leishmaniasis, particularly occurring in infection by Leishmania (L.) braziliensis species complex, ML is also a possible presentation of Old World leishmaniasis, in either L. donovani or L. major species complex infections. Thus, ML has to be considered not only as a Latin American disease but as an Old and New World disease. We describe ML epidemiology, pathogenesis, clinics, diagnosis, and therapy. Considering both its highly disfiguring lesions and its possible lethal outcome, ML should not be underestimated by physicians. Moreover, leishmaniasis is expected to increase its burden in many countries as sandfly vector distribution is widespreading towards non-endemic areas. Finally, the lack of clear understanding of ML pathogenesis and the absence of effective human vaccines strongly claim for more research. PMID:23853773

  2. Intestinal mucosal tolerance and impact of gut microbiota to mucosal tolerance

    PubMed Central

    Chistiakov, Dimitry A.; Bobryshev, Yuri V.; Kozarov, Emil; Sobenin, Igor A.; Orekhov, Alexander N.

    2015-01-01

    The mucosal barriers are very sensitive to pathogenic infection, thereby assuming the capacity of the mucosal immune system to induce protective immunity to harmful antigens and tolerance against harmless substances. This review provides current information about mechanisms of induction of mucosal tolerance and about impact of gut microbiota to mucosal tolerance. PMID:25628617

  3. Mechanism-based management for mucositis: option for treating side effects without compromising the efficacy of cancer therapy.

    PubMed

    Kwon, Youngjoo

    2016-01-01

    Mucositis is a major side effect induced by chemotherapy and radiotherapy. Although mucositis is a leading cause of morbidity and mortality in cancer patients, management is largely limited to controlling symptoms, and few therapeutic agents are available for treatment. Since mucositis could be inhibited by the modulation of radiotherapy- or chemotherapy-induced pathways independently of cancer treatment, there is an opportunity for the development of more targeted therapies and interventions. This article examined potential therapeutic agents that have been investigated for the prevention and/or inhibition of mucositis induced by conventional chemotherapy and radiotherapy. They can be classified according to their mechanisms of action: scavenging reactive oxygen species, inhibition of specific cytokine production or inflammation, and inhibition of apoptosis. These early events may be good target pathways for preventing the pathogenesis of mucositis. Considering that both cancer therapy and therapeutic agents for mucositis act on both normal and cancer cells, agents that inhibit mucositis should act through mechanisms that selectively protect normal cells without compromising cancer treatment. Therefore, mechanism-based guidance for the treatment of mucositis is critical to prevent risky treatments for cancer patients and to relieve detrimental side effects effectively from cancer therapy. PMID:27103826

  4. Mechanism-based management for mucositis: option for treating side effects without compromising the efficacy of cancer therapy

    PubMed Central

    Kwon, Youngjoo

    2016-01-01

    Mucositis is a major side effect induced by chemotherapy and radiotherapy. Although mucositis is a leading cause of morbidity and mortality in cancer patients, management is largely limited to controlling symptoms, and few therapeutic agents are available for treatment. Since mucositis could be inhibited by the modulation of radiotherapy- or chemotherapy-induced pathways independently of cancer treatment, there is an opportunity for the development of more targeted therapies and interventions. This article examined potential therapeutic agents that have been investigated for the prevention and/or inhibition of mucositis induced by conventional chemotherapy and radiotherapy. They can be classified according to their mechanisms of action: scavenging reactive oxygen species, inhibition of specific cytokine production or inflammation, and inhibition of apoptosis. These early events may be good target pathways for preventing the pathogenesis of mucositis. Considering that both cancer therapy and therapeutic agents for mucositis act on both normal and cancer cells, agents that inhibit mucositis should act through mechanisms that selectively protect normal cells without compromising cancer treatment. Therefore, mechanism-based guidance for the treatment of mucositis is critical to prevent risky treatments for cancer patients and to relieve detrimental side effects effectively from cancer therapy. PMID:27103826

  5. Immunology of Gut Mucosal Vaccines

    PubMed Central

    Pasetti, Marcela F.; Simon, Jakub K.; Sztein, Marcelo B.; Levine, Myron M.

    2011-01-01

    Summary Understanding the mechanisms underlying the induction of immunity in the gastrointestinal mucosa following oral immunization and the cross-talk between mucosal and systemic immunity should expedite the development of vaccines to diminish the global burden caused by enteric pathogens. Identifying an immunological correlate of protection in the course of field trials of efficacy, animal models (when available), or human challenge studies is also invaluable. In industrialized country populations, live attenuated vaccines (e.g. polio, typhoid, and rotavirus) mimic natural infection and generate robust protective immune responses. In contrast, a major challenge is to understand and overcome the barriers responsible for the diminished immunogenicity and efficacy of the same enteric vaccines in underprivileged populations in developing countries. Success in developing vaccines against some enteric pathogens has heretofore been elusive (e.g. Shigella). Different types of oral vaccines can selectively or inclusively elicit mucosal secretory immunoglobulin A and serum immunoglobulin G antibodies and a variety of cell-mediated immune responses. Areas of research that require acceleration include interaction between the gut innate immune system and the stimulation of adaptive immunity, development of safe yet effective mucosal adjuvants, better understanding of homing to the mucosa of immunologically relevant cells, and elicitation of mucosal immunologic memory. This review dissects the immune responses elicited in humans by enteric vaccines. PMID:21198669

  6. Prevention and treatment of chemo- and radiotherapy-induced oral mucositis.

    PubMed

    Demarosi, F; Bez, C; Carrassi, A

    2002-05-01

    The administration of many chemo-radiotherapy regimens in patients with cancer may be complicated by toxicities that limit the clinicians' abilities to deliver the most effective doses of active agents. Oral mucositis is a major dose-limiting toxic effect and the most important cause of morbidity in patients undergoing chemo-radiotherapy for head and neck cancers, in patients undergoing bone marrow transplantation and those receiving certain chemotherapeutic agents for a variety of human malignancies. The intent of this paper is to review preventive strategies and treatment approaches for patients with established oral mucositis. Many agents of differing mechanisms of action have been used in the prevention and treatment of oral mucositis induced by anticancer therapies. Currently, no intervention is completely successful at preventing or treating oral mucositis. The several solutions, drugs and methods used and studied in the prophylaxis and therapy of chemotherapy or radiotherapy-induced oral mucositis reflects the need of new, more efficient tools in the management of this complication. Current studies and our increasing understanding of the etiology and pathogenesis of oral mucositis will lead to new approaches to the management and improved quality of life for these patients. PMID:12070468

  7. Preventive and therapeutic effects of Smad7 on radiation-induced oral mucositis

    PubMed Central

    Han, Gangwen; Bian, Li; Li, Fulun; Cotrim, Ana; Wang, Donna; Lu, Jian Bo; Deng, Yu; Bird, Gregory; Sowers, Anastasia; Mitchell, James B.; Gutkind, J. Silvio; Zhao, Rui; Raben, David; Dijke, Peter ten; Refaeli, Yosef; Zhang, Qinghong; Wang, Xiao-Jing

    2013-01-01

    We report that K5.Smad7 mice, which express Smad7 transgene by a keratin-5 promoter, were resistant to radiation-induced oral mucositis, a painful oral ulceration. In addition to NF-κB activation known to contribute to oral mucositis, we found activated TGF-β signaling in oral mucositis. Smad7 dampened both pathways to attenuate inflammation, growth inhibition and apoptosis. Additionally, Smad7 promoted oral epithelial migration to close the wound. Further analyses revealed that TGF-β signaling Smads and their co-repressor CtBP1 transcriptionally repressed Rac1, and Smad7 abrogated this repression. Knocking down Rac1 in mouse keratinocytes abrogated Smad7-induced migration. Topically applying Smad7 protein with a cell permeable Tat-tag (Tat-Smad7) to oral mucosa showed preventive and therapeutic effects on radiation-induced oral mucositis in mice. Thus, we have identified novel molecular mechanisms involved in oral mucositis pathogenesis and our data suggest an alternative therapeutic strategy to block multiple pathological processes of oral mucositis. PMID:23475202

  8. Immune Responses to HIV and SIV in Mucosal Tissues: “Location, Location, Location”

    PubMed Central

    Shacklett, Barbara L.

    2010-01-01

    Purpose of review This review summarizes research literature regarding mucosal immunity to HIV and SIV, with an emphasis on work published within the past 18 months. Recent findings Notable recent studies have focused on the pivotal events occurring within mucosal tissues during acute HIV/SIV infection that serve to establish a balance between detrimental immune activation and beneficial adaptive responses. In cervicovaginal mucosa, an early inflammatory response leads to recruitment of susceptible target cells. At this acute stage, the in vivo ratio between CD8+ effector cells and infected CD4+ T-cells may be critical for limiting viral dissemination. Acute infection is also accompanied by loss of germinal center architecture and T/B cell apoptosis in Peyer’s patches of the gastrointestinal tract. During chronic infection, mucosal CD8+ T-cells may play a role in immune control, as suggested by studies of elite controllers. Summary Mucosal tissues serve as the major portal of entry for HIV, and house a majority of the body’s lymphocytes, including CD4+ T-cells that are targets for infection. Recent studies have focused renewed attention on events occurring immediately after transmission, and underscore the concept that the balance between inflammation and protective immunity is established by host responses in mucosal tissues. PMID:20543589

  9. The Mucosal Immune System of Teleost Fish

    PubMed Central

    Salinas, Irene

    2015-01-01

    Teleost fish possess an adaptive immune system associated with each of their mucosal body surfaces. Evidence obtained from mucosal vaccination and mucosal infection studies reveal that adaptive immune responses take place at the different mucosal surfaces of teleost. The main mucosa-associated lymphoid tissues (MALT) of teleosts are the gut-associated lymphoid tissue (GALT), skin-associated lymphoid tissue (SALT), the gill-associated lymphoid tissue (GIALT) and the recently discovered nasopharynx-associated lymphoid tissue (NALT). Teleost MALT includes diffuse B cells and T cells with specific phenotypes different from their systemic counterparts that have co-evolved to defend the microbe-rich mucosal environment. Both B and T cells respond to mucosal infection or vaccination. Specific antibody responses can be measured in the gills, gut and skin mucosal secretions of teleost fish following mucosal infection or vaccination. Rainbow trout studies have shown that IgT antibodies and IgT+ B cells are the predominant B cell subset in all MALT and respond in a compartmentalized manner to mucosal infection. Our current knowledge on adaptive immunity in teleosts is limited compared to the mammalian literature. New research tools and in vivo models are currently being developed in order to help reveal the great intricacy of teleost mucosal adaptive immunity and help improve mucosal vaccination protocols for use in aquaculture. PMID:26274978

  10. Viral diseases and pathogenesis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It includes classification of viral infection. It describes common ways of virus entry, replication, and transmission. It introduces the routes of viral invasion and molecular basis for viral pathogenesis....

  11. Arterivirus molecular biology and pathogenesis.

    PubMed

    Snijder, Eric J; Kikkert, Marjolein; Fang, Ying

    2013-10-01

    Arteriviruses are positive-stranded RNA viruses that infect mammals. They can cause persistent or asymptomatic infections, but also acute disease associated with a respiratory syndrome, abortion or lethal haemorrhagic fever. During the past two decades, porcine reproductive and respiratory syndrome virus (PRRSV) and, to a lesser extent, equine arteritis virus (EAV) have attracted attention as veterinary pathogens with significant economic impact. Particularly noteworthy were the 'porcine high fever disease' outbreaks in South-East Asia and the emergence of new virulent PRRSV strains in the USA. Recently, the family was expanded with several previously unknown arteriviruses isolated from different African monkey species. At the molecular level, arteriviruses share an intriguing but distant evolutionary relationship with coronaviruses and other members of the order Nidovirales. Nevertheless, several of their characteristics are unique, including virion composition and structure, and the conservation of only a subset of the replicase domains encountered in nidoviruses with larger genomes. During the past 15 years, the advent of reverse genetics systems for EAV and PRRSV has changed and accelerated the structure-function analysis of arterivirus RNA and protein sequences. These systems now also facilitate studies into host immune responses and arterivirus immune evasion and pathogenesis. In this review, we have summarized recent advances in the areas of arterivirus genome expression, RNA and protein functions, virion architecture, virus-host interactions, immunity, and pathogenesis. We have also briefly reviewed the impact of these advances on disease management, the engineering of novel candidate live vaccines and the diagnosis of arterivirus infection. PMID:23939974

  12. Dendritic cell-targeting DNA-based mucosal adjuvants for the development of mucosal vaccines

    PubMed Central

    Kataoka, Kosuke; Fujihashi, Kohtaro

    2009-01-01

    In order to establish effective mucosal immunity against various mucosal pathogens, vaccines must be delivered via the mucosal route and contain effective adjuvant(s). Since mucosal adjuvants can simply mix with the antigen, it is relatively easy to adapt them for different types of vaccine development. Even in simple admixture vaccines, the adjuvant itself must be prepared without any complications. Thus, CpG oligodeoxynucleotides or plasmids encoding certain cDNA(s) would be potent mucosal adjuvant candidates when compared with other substances that can be used as mucosal adjuvants. The strategy of a DNA-based mucosal adjuvant facilitates the targeting of mucosal dendritic cells, and thus is an effective and safe approach. It would also provide great flexibility for the development of effective vaccines for various mucosal pathogens. PMID:19722892

  13. Doxepin Rinse Versus Placebo in the Treatment of Acute Oral Mucositis Pain in Patients Receiving Head and Neck Radiotherapy With or Without Chemotherapy: A Phase III, Randomized, Double-Blind Trial (NCCTG-N09C6 [Alliance])

    PubMed Central

    Leenstra, James L.; Miller, Robert C.; Qin, Rui; Martenson, James A.; Dornfeld, Kenneth J.; Bearden, James D.; Puri, Dev R.; Stella, Philip J.; Mazurczak, Miroslaw A.; Klish, Marie D.; Novotny, Paul J.; Foote, Robert L.; Loprinzi, Charles L.

    2014-01-01

    Purpose Painful oral mucositis (OM) is a significant toxicity during radiotherapy for head and neck cancers. The aim of this randomized, double-blind, placebo-controlled trial was to test the efficacy of doxepin hydrochloride in the reduction of radiotherapy-induced OM pain. Patients and Methods In all, 155 patients were randomly allocated to a doxepin oral rinse or a placebo for the treatment of radiotherapy-related OM pain. Patients received a single dose of doxepin or placebo on day 1 and then crossed over to receive the opposite agent on a subsequent day. Pain questionnaires were administered at baseline and at 5, 15, 30, 60, 120, and 240 minutes. Patients were then given the option to continue doxepin. The primary end point was pain reduction as measured by the area under the curve (AUC) of the pain scale using data from day 1. Results Primary end point analysis revealed that the AUC for mouth and throat pain reduction was greater for doxepin (−9.1) than for placebo (−4.7; P < .001). Crossover analysis of patients completing both phases confirmed that patients experienced greater mouth and throat pain reduction with doxepin (intrapatient changes of 4.1 for doxepin-placebo arm and −2.8 for placebo-doxepin arm; P < .001). Doxepin was associated with more stinging or burning, unpleasant taste, and greater drowsiness than the placebo rinse. More patients receiving doxepin expressed a desire to continue treatment than did patients with placebo after completion of each of the randomized phases of the study. Conclusion A doxepin rinse diminishes OM pain. Further studies are warranted to determine its role in the management of OM. PMID:24733799

  14. Mucosal vaccination: lung versus nose.

    PubMed

    Vujanic, Ana; Sutton, Philip; Snibson, Kenneth J; Yen, Hung-Hsun; Scheerlinck, Jean-Pierre Y

    2012-07-15

    The induction of potent mucosal immune responses able to prevent the establishment of infection at the onset of mucosal pathogen colonisation represents a desirable but challenging goal for vaccine development. Here we compare nasal vaccine delivery with intra-pulmonary vaccination using a sheep lymphatic cannulation model. Our results demonstrate that nasal delivery of a non-infective ISCOMATRIX(®) influenza vaccine does not induce primary immune responses in the lymph draining the nasal lymph nodes, suggesting that local immune responses in the lymph nodes draining the nasal cavity are relatively weak. However, this mode of delivery can boost existing immunity in the nasal lymph. Using the same adjuvant we were able to induce very potent immune responses in both blood and bronchoalveolar lavage (BAL), following intra-pulmonary delivery of ISCOMATRIX(®) influenza vaccine, even when very small doses of antigen were employed. Lung delivery could also induce comparable immune responses against other recombinant antigens mixed with ISCOMATRIX(®) adjuvant and could therefore become a method of choice for the induction of immunity to mucosal pathogens infecting the lower respiratory tract. PMID:21492942

  15. Cryopreservation of Human Mucosal Leukocytes

    PubMed Central

    Shu, Zhiquan; Levy, Claire N.; Ferre, April L.; Hartig, Heather; Fang, Cifeng; Lentz, Gretchen; Fialkow, Michael; Kirby, Anna C.; Adams Waldorf, Kristina M.; Veazey, Ronald S.; Germann, Anja; von Briesen, Hagen; McElrath, M. Juliana; Dezzutti, Charlene S.; Sinclair, Elizabeth; Baker, Chris A. R.; Shacklett, Barbara L.; Gao, Dayong; Hladik, Florian

    2016-01-01

    Background Understanding how leukocytes in the cervicovaginal and colorectal mucosae respond to pathogens, and how medical interventions affect these responses, is important for developing better tools to prevent HIV and other sexually transmitted infections. An effective cryopreservation protocol for these cells following their isolation will make studying them more feasible. Methods and Findings To find an optimal cryopreservation protocol for mucosal mononuclear leukocytes, we compared cryopreservation media and procedures using human vaginal leukocytes and confirmed our results with endocervical and colorectal leukocytes. Specifically, we measured the recovery of viable vaginal T cells and macrophages after cryopreservation with different cryopreservation media and handling procedures. We found several cryopreservation media that led to recoveries above 75%. Limiting the number and volume of washes increased the fraction of cells recovered by 10–15%, possibly due to the small cell numbers in mucosal samples. We confirmed that our cryopreservation protocol also works well for both endocervical and colorectal leukocytes. Cryopreserved leukocytes had slightly increased cytokine responses to antigenic stimulation relative to the same cells tested fresh. Additionally, we tested whether it is better to cryopreserve endocervical cells on the cytobrush or in suspension. Conclusions Leukocytes from cervicovaginal and colorectal tissues can be cryopreserved with good recovery of functional, viable cells using several different cryopreservation media. The number and volume of washes has an experimentally meaningful effect on the percentage of cells recovered. We provide a detailed, step-by-step protocol with best practices for cryopreservation of mucosal leukocytes. PMID:27232996

  16. Mucosal Immunology of Food Allergy

    PubMed Central

    Berin, M. Cecilia; Sampson, Hugh A.

    2013-01-01

    Food allergies are increasing in prevalence at a higher rate than can be explained by genetic factors, suggesting a role for as yet unidentified environmental factors. In this review, we summarize the state of knowledge about the healthy immune response to antigens in the diet and the basis of immune deviation that results in IgE sensitization and allergic reactivity to foods. The intestinal epithelium forms the interface between the external environment and the mucosal immune system, and emerging data suggest that the interaction between intestinal epithelial cells and mucosal dendritic cells is of particular importance in determining the outcome of immune responses to dietary antigens. Exposure to food allergens through non-oral routes, in particular through the skin, is increasingly recognized as a potentially important factor in the increasing rate of food allergy. There are many open questions on the role of environmental factors such as dietary factors and microbiota in the development of food allergy, but data suggest that both have an important modulatory effect on the mucosal immune system. Finally, we discuss recent developments in our understanding of immune mechanisms of clinical manifestations of food allergy. New experimental tools, particularly in the field of genomics and microbiome, are likely to shed light on factors responsible for the growing clinical problem of food allergy. PMID:23660362

  17. Serum zinc levels in 368 patients with oral mucosal diseases: A preliminary study

    PubMed Central

    Bao, Zhe-Xuan; Yang, Xiao-Wen; Shi, Jing

    2016-01-01

    Background The aim of this study was to assess the serum zinc levels in patients with common oral mucosal diseases by comparing these to healthy controls. Material and Methods A total of 368 patients, which consisted of 156 recurrent aphthous stomatitis (RAS) patients, 57 oral lichen planus (OLP) patients, 55 burning mouth syndrome (BMS) patients, 54 atrophic glossitis (AG) patients, 46 xerostomia patients, and 115 sex-and age-matched healthy control subjects were enrolled in this study. Serum zinc levels were measured in all participants. Statistical analysis was performed using a one-way ANOVA, t-test, and Chi-square test. Results The mean serum zinc level in the healthy control group was significantly higher than the levels of all other groups (p < 0.001). No individual in the healthy control group had a serum zinc level less than the minimum normal value. However, up to 24.7% (13/54) of patients with AG presented with zinc deficiency, while 21.2% (33/156) of patients with RAS, 16.4% (9/55) of patients with BMS, 15.2% (7/46) of patients with xerostomia, and 14.0% (8/57) of patients with OLP were zinc deficient. Altogether, the zinc deficiency rate was 19.02% (70/368) in the oral mucosal diseases (OMD) group (all patients with OMD). The difference between the OMD and healthy control group was significant (p <0.001). Gender differences in serum zinc levels were also present, although not statistically significant. Conclusions Zinc deficiency may be involved in the pathogenesis of common oral mucosal diseases. Zinc supplementation may be a useful treatment for oral mucosal diseases, but this requires further investigation; the optimal serum level of zinc, for the prevention and treatment of oral mucosal diseases, remains to be determined. Key words:Oral mucosal diseases, Zinc deficiency, pathogenesis. PMID:27031065

  18. Acute Pneumonia.

    PubMed

    Arshad, Hammad; Fasanya, Adebayo; Cheema, Tariq; Singh, Anil C

    2016-01-01

    Acute pneumonia is an active infection of the lungs that results when an individual at risk gets exposed to a particular microbiological pathogen. Acute pneumonia is the leading cause of death in the United States that is attributable to an infection. The risk factors, pathogenesis, and microbiological organisms involved differ if the pneumonia develops in the community versus health care-associated environment. The development of concise and comprehensive guidelines has led to an improvement in the management of the problem. However, the emergence of multidrug-resistant organisms and the increase in the percentage of elderly population keep mortality risk very substantial. PMID:26919676

  19. Management of chemo/radiation-induced oral mucositis in patients with head and neck cancer: A review of the current literature.

    PubMed

    Moslemi, Dariush; Nokhandani, Akram Mohammadi; Otaghsaraei, Mahsa Taheri; Moghadamnia, Yasaman; Kazemi, Sohrab; Moghadamnia, Ali Akbar

    2016-07-01

    Oropharyngeal mucositis is an important complication in non-surgical cancer treatments. It represents the major complication in radiotherapy of tumors located in head and neck areas. Many results have been published in order to define the best clinical protocol for prophylaxis or treatment of mucositis, but a consensus has not been attained yet. In this review, some recent topics in prophylaxis and treatment of mucositis related to radiation therapy are reconsidered using PUBMED and GOOGLE SCHOOLAR search engines from 2000 to 2015. In this review, more than 100 clinical studies have been selected and divided into the prophylactic or therapeutic uses of the evaluated treatment agents. The number of patients and kind of study design, the clinical features, prevalence, risk factors, pathogenesis, diagnosis, complication, prophylaxis and the treatment of mucositis were also specified. Nevertheless, it has not been truly achieved a consensus protocol of prophylaxis and treatment of oral mucositis. PMID:27113797

  20. Pathogenesis of Castleman's Disease.

    PubMed

    Zhang, Lu; Li, Jian

    2016-02-01

    Castleman's disease (CD) is a rare lymphoproliferative disorder that comprises at least two distinct clinical subtypes (unicentric and multicentric). Three pathologic variants (hyaline vascular variant, plasma cell variant, and mixed variant) have been recognized. In addition to interleukin-6 and human herpes virus 8, some other cytokines and viruses may also be involved in the pathogenesis of CD. This review summarizes the recent advances in the underlying pathogenesis of CD, with an attempt to provide evidence for new treatment options that may change the current treatment strategies and improve patients' outcomes. PMID:26956866

  1. Pathogenesis of Crohn's disease

    PubMed Central

    Boyapati, Ray; Satsangi, Jack

    2015-01-01

    Significant progress in our understanding of Crohn's disease (CD), an archetypal common, complex disease, has now been achieved. Our ability to interrogate the deep complexities of the biological processes involved in maintaining gut mucosal homeostasis is a major over-riding factor underpinning this rapid progress. Key studies now offer many novel and expansive insights into the interacting roles of genetic susceptibility, immune function, and the gut microbiota in CD. Here, we provide overviews of these recent advances and new mechanistic themes, and address the challenges and prospects for translation from concept to clinic. PMID:26097717

  2. Pathogenesis of Crohn's disease.

    PubMed

    Boyapati, Ray; Satsangi, Jack; Ho, Gwo-Tzer

    2015-01-01

    Significant progress in our understanding of Crohn's disease (CD), an archetypal common, complex disease, has now been achieved. Our ability to interrogate the deep complexities of the biological processes involved in maintaining gut mucosal homeostasis is a major over-riding factor underpinning this rapid progress. Key studies now offer many novel and expansive insights into the interacting roles of genetic susceptibility, immune function, and the gut microbiota in CD. Here, we provide overviews of these recent advances and new mechanistic themes, and address the challenges and prospects for translation from concept to clinic. PMID:26097717

  3. A Metaproteomic Approach to Study Human-Microbial Ecosystems at the Mucosal Luminal Interface

    PubMed Central

    Li, Xiaoxiao; LeBlanc, James; Truong, Allison; Vuthoori, Ravi; Chen, Sharon S.; Lustgarten, Jonathan L.; Roth, Bennett; Allard, Jeff; Ippoliti, Andrew; Presley, Laura L.; Borneman, James; Bigbee, William L.; Gopalakrishnan, Vanathi; Graeber, Thomas G.; Elashoff, David

    2011-01-01

    Aberrant interactions between the host and the intestinal bacteria are thought to contribute to the pathogenesis of many digestive diseases. However, studying the complex ecosystem at the human mucosal-luminal interface (MLI) is challenging and requires an integrative systems biology approach. Therefore, we developed a novel method integrating lavage sampling of the human mucosal surface, high-throughput proteomics, and a unique suite of bioinformatic and statistical analyses. Shotgun proteomic analysis of secreted proteins recovered from the MLI confirmed the presence of both human and bacterial components. To profile the MLI metaproteome, we collected 205 mucosal lavage samples from 38 healthy subjects, and subjected them to high-throughput proteomics. The spectral data were subjected to a rigorous data processing pipeline to optimize suitability for quantitation and analysis, and then were evaluated using a set of biostatistical tools. Compared to the mucosal transcriptome, the MLI metaproteome was enriched for extracellular proteins involved in response to stimulus and immune system processes. Analysis of the metaproteome revealed significant individual-related as well as anatomic region-related (biogeographic) features. Quantitative shotgun proteomics established the identity and confirmed the biogeographic association of 49 proteins (including 3 functional protein networks) demarcating the proximal and distal colon. This robust and integrated proteomic approach is thus effective for identifying functional features of the human mucosal ecosystem, and a fresh understanding of the basic biology and disease processes at the MLI. PMID:22132074

  4. Irritable bowel syndrome: diagnosis and pathogenesis.

    PubMed

    El-Salhy, Magdy

    2012-10-01

    Irritable bowel syndrome (IBS) is a common gastrointestinal (GI) disorder that considerably reduces the quality of life. It further represents an economic burden on society due to the high consumption of healthcare resources and the non-productivity of IBS patients. The diagnosis of IBS is based on symptom assessment and the Rome III criteria. A combination of the Rome III criteria, a physical examination, blood tests, gastroscopy and colonoscopy with biopsies is believed to be necessary for diagnosis. Duodenal chromogranin A cell density is a promising biomarker for the diagnosis of IBS. The pathogenesis of IBS seems to be multifactorial, with the following factors playing a central role in the pathogenesis of IBS: heritability and genetics, dietary/intestinal microbiota, low-grade inflammation, and disturbances in the neuroendocrine system (NES) of the gut. One hypothesis proposes that the cause of IBS is an altered NES, which would cause abnormal GI motility, secretions and sensation. All of these abnormalities are characteristic of IBS. Alterations in the NES could be the result of one or more of the following: genetic factors, dietary intake, intestinal flora, or low-grade inflammation. Post-infectious IBS (PI-IBS) and inflammatory bowel disease-associated IBS (IBD-IBS) represent a considerable subset of IBS cases. Patients with PI- and IBD-IBS exhibit low-grade mucosal inflammation, as well as abnormalities in the NES of the gut. PMID:23066308

  5. Helicobacter pylori virulence and cancer pathogenesis

    PubMed Central

    Yamaoka, Yoshio; Graham, David Y

    2014-01-01

    Helicobacter pylori is human gastric pathogen that causes chronic and progressive gastric mucosal inflammation and is responsible for the gastric inflammation-associated diseases, gastric cancer and peptic ulcer disease. specific outcomes reflect the interplay between host-, environmental- and bacterial-specific factors. Progress in understanding putative virulence factors in disease pathogenesis has been limited and many false leads have consumed scarce resources. Few in vitro–in vivo correlations or translational applications have proved clinically relevant. Reported virulence factor-related outcomes reflect differences in relative risk of disease rather than specificity for any specific outcome. Studies of individual virulence factor associations have provided conflicting results. Since virulence factors are linked, studies of groups of putative virulence factors are needed to provide clinically useful information. Here, the authors discuss the progress made in understanding the role of H. pylori virulence factors CagA, vacuolating cytotoxin, OipA and DupA in disease pathogenesis and provide suggestions for future studies. PMID:25052757

  6. Irritable bowel syndrome: Diagnosis and pathogenesis

    PubMed Central

    El-Salhy, Magdy

    2012-01-01

    Irritable bowel syndrome (IBS) is a common gastrointestinal (GI) disorder that considerably reduces the quality of life. It further represents an economic burden on society due to the high consumption of healthcare resources and the non-productivity of IBS patients. The diagnosis of IBS is based on symptom assessment and the Rome III criteria. A combination of the Rome III criteria, a physical examination, blood tests, gastroscopy and colonoscopy with biopsies is believed to be necessary for diagnosis. Duodenal chromogranin A cell density is a promising biomarker for the diagnosis of IBS. The pathogenesis of IBS seems to be multifactorial, with the following factors playing a central role in the pathogenesis of IBS: heritability and genetics, dietary/intestinal microbiota, low-grade inflammation, and disturbances in the neuroendocrine system (NES) of the gut. One hypothesis proposes that the cause of IBS is an altered NES, which would cause abnormal GI motility, secretions and sensation. All of these abnormalities are characteristic of IBS. Alterations in the NES could be the result of one or more of the following: genetic factors, dietary intake, intestinal flora, or low-grade inflammation. Post-infectious IBS (PI-IBS) and inflammatory bowel disease-associated IBS (IBD-IBS) represent a considerable subset of IBS cases. Patients with PI- and IBD-IBS exhibit low-grade mucosal inflammation, as well as abnormalities in the NES of the gut. PMID:23066308

  7. Voice Disorders in Mucosal Leishmaniasis

    PubMed Central

    Ruas, Ana Cristina Nunes; Lucena, Márcia Mendonça; da Costa, Ananda Dutra; Vieira, Jéssica Rafael; de Araújo-Melo, Maria Helena; Terceiro, Benivaldo Ramos Ferreira; de Sousa Torraca, Tania Salgado; de Oliveira Schubach, Armando; Valete-Rosalino, Claudia Maria

    2014-01-01

    Introduction Leishmaniasis is considered as one of the six most important infectious diseases because of its high detection coefficient and ability to produce deformities. In most cases, mucosal leishmaniasis (ML) occurs as a consequence of cutaneous leishmaniasis. If left untreated, mucosal lesions can leave sequelae, interfering in the swallowing, breathing, voice and speech processes and requiring rehabilitation. Objective To describe the anatomical characteristics and voice quality of ML patients. Materials and Methods A descriptive transversal study was conducted in a cohort of ML patients treated at the Laboratory for Leishmaniasis Surveillance of the Evandro Chagas National Institute of Infectious Diseases - Fiocruz, between 2010 and 2013. The patients were submitted to otorhinolaryngologic clinical examination by endoscopy of the upper airways and digestive tract and to speech-language assessment through directed anamnesis, auditory perception, phonation times and vocal acoustic analysis. The variables of interest were epidemiologic (sex and age) and clinic (lesion location, associated symptoms and voice quality. Results 26 patients under ML treatment and monitored by speech therapists were studied. 21 (81%) were male and five (19%) female, with ages ranging from 15 to 78 years (54.5+15.0 years). The lesions were distributed in the following structures 88.5% nasal, 38.5% oral, 34.6% pharyngeal and 19.2% laryngeal, with some patients presenting lesions in more than one anatomic site. The main complaint was nasal obstruction (73.1%), followed by dysphonia (38.5%), odynophagia (30.8%) and dysphagia (26.9%). 23 patients (84.6%) presented voice quality perturbations. Dysphonia was significantly associated to lesions in the larynx, pharynx and oral cavity. Conclusion We observed that vocal quality perturbations are frequent in patients with mucosal leishmaniasis, even without laryngeal lesions; they are probably associated to disorders of some resonance

  8. Inflammatory bowel disease: Pathogenesis

    PubMed Central

    Zhang, Yi-Zhen; Li, Yong-Yu

    2014-01-01

    Inflammatory bowel disease (IBD), including Crohn’s disease and ulcerative colitis, is characterized by chronic relapsing intestinal inflammation. It has been a worldwide health-care problem with a continually increasing incidence. It is thought that IBD results from an aberrant and continuing immune response to the microbes in the gut, catalyzed by the genetic susceptibility of the individual. Although the etiology of IBD remains largely unknown, it involves a complex interaction between the genetic, environmental or microbial factors and the immune responses. Of the four components of IBD pathogenesis, most rapid progress has been made in the genetic study of gut inflammation. The latest internationally collaborative studies have ascertained 163 susceptibility gene loci for IBD. The genes implicated in childhood-onset and adult-onset IBD overlap, suggesting similar genetic predispositions. However, the fact that genetic factors account for only a portion of overall disease variance indicates that microbial and environmental factors may interact with genetic elements in the pathogenesis of IBD. Meanwhile, the adaptive immune response has been classically considered to play a major role in the pathogenesis of IBD, as new studies in immunology and genetics have clarified that the innate immune response maintains the same importance in inducing gut inflammation. Recent progress in understanding IBD pathogenesis sheds lights on relevant disease mechanisms, including the innate and adaptive immunity, and the interactions between genetic factors and microbial and environmental cues. In this review, we provide an update on the major advances that have occurred in above areas. PMID:24415861

  9. Hepatitis E Pathogenesis.

    PubMed

    Lhomme, Sébastien; Marion, Olivier; Abravanel, Florence; Chapuy-Regaud, Sabine; Kamar, Nassim; Izopet, Jacques

    2016-01-01

    Although most hepatitis E virus (HEV) infections are asymptomatic, some can be severe, causing fulminant hepatitis and extra-hepatic manifestations, including neurological and kidney injuries. Chronic HEV infections may also occur in immunocompromised patients. This review describes how our understanding of the pathogenesis of HEV infection has progressed in recent years. PMID:27527210

  10. [Pathogenesis of hypophosphatemia].

    PubMed

    Takeuchi, Yasuhiro

    2016-02-01

    Chronic hypophosphatemia is seriously involved in several disorders of musculoskeletal system. Symptoms of patients are usually non-specific, such as pain with or without muscle weakness on lower extremities and are often hard to be correctly diagnosed. It is clinically important for physicians to understand pathogenesis and clinical features of hypophosphatemia and its related diseases. PMID:26813499

  11. Hepatitis E Pathogenesis

    PubMed Central

    Lhomme, Sébastien; Marion, Olivier; Abravanel, Florence; Chapuy-Regaud, Sabine; Kamar, Nassim; Izopet, Jacques

    2016-01-01

    Although most hepatitis E virus (HEV) infections are asymptomatic, some can be severe, causing fulminant hepatitis and extra-hepatic manifestations, including neurological and kidney injuries. Chronic HEV infections may also occur in immunocompromised patients. This review describes how our understanding of the pathogenesis of HEV infection has progressed in recent years. PMID:27527210

  12. Eosinophils in mucosal immune responses

    PubMed Central

    Travers, J; Rothenberg, M E

    2015-01-01

    Eosinophils, multifunctional cells that contribute to both innate and adaptive immunity, are involved in the initiation, propagation and resolution of immune responses, including tissue repair. They achieve this multifunctionality by expression of a diverse set of activation receptors, including those that directly recognize pathogens and opsonized targets, and by their ability to store and release preformed cytotoxic mediators that participate in host defense, to produce a variety of de novo pleotropic mediators and cytokines and to interact directly and indirectly with diverse cell types, including adaptive and innate immunocytes and structural cells. Herein, we review the basic biology of eosinophils and then focus on new emerging concepts about their role in mucosal immune homeostasis, particularly maintenance of intestinal IgA. We review emerging data about their development and regulation and describe new concepts concerning mucosal eosinophilic diseases. We describe recently developed therapeutic strategies to modify eosinophil levels and function and provide collective insight about the beneficial and detrimental functions of these enigmatic cells. PMID:25807184

  13. Biology and Mucosal Immunity to Myxozoans

    PubMed Central

    Gómez, Daniela; Bartholomew, Jerri; Sunyer, J. Oriol

    2014-01-01

    Myxozoans are among the most abundant parasites in nature. Their life cycles involve two hosts: an invertebrate, usually an annelid, and a vertebrate, usually a fish. They affect fish species in their natural habitats but also constitute a menace for fish aquaculture. Using different strategies they are able to parasitize and cause damage in multiple organs, including mucosal tissues, which they use also as portals of entry. In fish, the main mucosal sites include the intestine, skin and gills. Recently the finding of a specific mucosal immunoglobulin in teleost (IgT), analogous to mammalian IgA, and the capacity of fish to develop a specific mucosal immune response against different pathogens, has highlighted the importance of studying immune responses at mucosal sites. In this review, we describe the major biological characteristics of myxozoan parasites and present the data available regarding immune responses for species that infect mucosal sites. As models for mucosal immunity we review the responses to Enteromyxum spp. and Ceratomyxa shasta, both of which parasitize the intestine. The immune response at the skin and gills is also described, as these mucosal tissues are used by myxozoans as attaching surfaces and portal of entry, and some species also parasitize these sites. Finally, the development of immunoprophylactic strategies is discussed. PMID:23994774

  14. Vaccination Strategies for Mucosal Immune Responses

    PubMed Central

    Ogra, Pearay L.; Faden, Howard; Welliver, Robert C.

    2001-01-01

    Mucosal administration of vaccines is an important approach to the induction of appropriate immune responses to microbial and other environmental antigens in systemic sites and peripheral blood as well as in most external mucosal surfaces. The development of specific antibody- or T-cell-mediated immunologic responses and the induction of mucosally induced systemic immunologic hyporesponsiveness (oral or mucosal tolerance) depend on complex sets of immunologic events, including the nature of the antigenic stimulation of specialized lymphoid structures in the host, antigen-induced activation of different populations of regulatory T cells (Th1 versus Th2), and the expression of proinflammatory and immunoregulatory cytokines. Availability of mucosal vaccines will provide a painless approach to deliver large numbers of vaccine antigens for human immunization. Currently, an average infant will receive 20 to 25 percutaneous injections for vaccination against different childhood infections by 18 months of age. It should be possible to develop for human use effective, nonliving, recombinant, replicating, transgenic, and microbial vector- or plant-based mucosal vaccines to prevent infections. Based on the experience with many dietary antigens, it is also possible to manipulate the mucosal immune system to induce systemic tolerance against environmental, dietary, and possibly other autoantigens associated with allergic and autoimmune disorders. Mucosal immunity offers new strategies to induce protective immune responses against a variety of infectious agents. Such immunization may also provide new prophylactic or therapeutic avenues in the control of autoimmune diseases in humans. PMID:11292646

  15. An outbreak of mucosal disease in a dairy herd.

    PubMed

    Løken, T; Gamlem, H; Lysbakken, O

    1989-01-01

    An outbreak of mucosal disease (MD) was studied in a dairy herd, comprising 12 cows, 9 heifers and 18 calves. During a period of 1 month, six 5 to 8 month-old calves showed typical signs of MD. They all died or were killed in extremis after 2-8 days with progressively worsening clinical signs. Post mortem lesions were examined in one calf. Non-cytopathogenic MD virus was isolated from serum or tissues from 3 clinically affected calves and from 1 healthy heifer. All cows and heifers except for the viremic one possessed neutralizing antibodies against bovine pestivirus. According to the current MD-pathogenesis concept, the affected calves were probably infected transplacentally during the first half of foetal life with pestivirus from the persistently infected heifer in the herd. PMID:2629507

  16. Schwannomas and their pathogenesis.

    PubMed

    Hilton, David A; Hanemann, Clemens Oliver

    2014-04-01

    Schwannomas may occur spontaneously, or in the context of a familial tumor syndrome such as neurofibromatosis type 2 (NF2), schwannomatosis and Carney's complex. Schwannomas have a variety of morphological appearances, but they behave as World Health Organization (WHO) grade I tumors, and only very rarely undergo malignant transformation. Central to the pathogenesis of these tumors is loss of function of merlin, either by direct genetic change involving the NF2 gene on chromosome 22 or secondarily to merlin inactivation. The genetic pathways and morphological features of schwannomas associated with different genetic syndromes will be discussed. Merlin has multiple functions, including within the nucleus and at the cell membrane, and this review summarizes our current understanding of the mechanisms by which merlin loss is involved in schwannoma pathogenesis, highlighting potential areas for therapeutic intervention. PMID:24450866

  17. Chronic rhinosinusitis pathogenesis.

    PubMed

    Stevens, Whitney W; Lee, Robert J; Schleimer, Robert P; Cohen, Noam A

    2015-12-01

    There are a variety of medical conditions associated with chronic sinonasal inflammation, including chronic rhinosinusitis (CRS) and cystic fibrosis. In particular, CRS can be divided into 2 major subgroups based on whether nasal polyps are present or absent. Unfortunately, clinical treatment strategies for patients with chronic sinonasal inflammation are limited, in part because the underlying mechanisms contributing to disease pathology are heterogeneous and not entirely known. It is hypothesized that alterations in mucociliary clearance, abnormalities in the sinonasal epithelial cell barrier, and tissue remodeling all contribute to the chronic inflammatory and tissue-deforming processes characteristic of CRS. Additionally, the host innate and adaptive immune responses are also significantly activated and might be involved in pathogenesis. Recent advancements in the understanding of CRS pathogenesis are highlighted in this review, with special focus placed on the roles of epithelial cells and the host immune response in patients with cystic fibrosis, CRS without nasal polyps, or CRS with nasal polyps. PMID:26654193

  18. [Pathogenesis of psoriasis].

    PubMed

    Schäkel, K; Schön, M P; Ghoreschi, K

    2016-06-01

    Psoriasis is an inflammatory T cell-mediated autoimmune disease of skin and joints that affects 2-4 % of the adult population and 0.1-1 % of children. Genetic susceptibility, environmental triggering factors, and innate immune processes initiate psoriasis pathogenesis that results in an adaptive autoreactive response. The T cell response is orchestrated by CD 8(+) T cells in the epidermis and by CD 4(+) T cells in the dermis that predominantly produce interleukin-17 (IL‑17). Research of the past 15 years unraveled cellular and molecular mechanisms as well as cytokines like TNF-α or IL‑23 that contribute to psoriatic inflammation. This knowledge has been translated into clinical practice and a number of antipsoriatic small molecules and immunobiologics are now available. Here, we discuss the current principles of psoriasis pathogenesis in the context of modern therapies. PMID:27246016

  19. Mucosal Antibodies Induced by Intranasal but Not Intramuscular Immunization Block Norovirus GII.4 Virus-Like Particle Receptor Binding.

    PubMed

    Tamminen, Kirsi; Malm, Maria; Vesikari, Timo; Blazevic, Vesna

    2016-06-01

    Noroviruses (NoVs) account for the majority of diagnosed cases of viral acute gastroenteritis worldwide. Virus-like particle (VLP)-based vaccines against NoV are currently under development. Serum antibodies that block the binding of NoV VLPs to histo-blood group antigens, the putative receptors for NoV, correlate with protection against NoV infection. The role of functional mucosal antibodies in protection is largely unknown, even though the intestinal mucosa is the entry port for NoV. Balb/c mice were immunized intramuscularly (IM) or intranasally (IN) with NoV GII.4 VLPs, and systemic and mucosal blocking antibody responses were studied. IN immunization elicited NoV-specific serum and mucosal IgG and IgA antibodies, whereas IM immunized animals completely lacked IgA. Both immunization routes induced similar blocking activity in serum but only IN route generated blocking antibodies in mucosa. The level of IgA in the mucosal (nasal) lavages strongly correlated (r = 0.841) with the blocking activity, suggesting that IgA, but not IgG, is the major NoV blocking antibody on mucosal surfaces. The results indicate that only mucosal immunization route induces the development of functional anti-NoV IgA on mucosal surface. PMID:27135874

  20. An NK Cell Perforin Response Elicited via IL-18 Controls Mucosal Inflammation Kinetics during Salmonella Gut Infection.

    PubMed

    Müller, Anna A; Dolowschiak, Tamas; Sellin, Mikael E; Felmy, Boas; Verbree, Carolin; Gadient, Sandra; Westermann, Alexander J; Vogel, Jörg; LeibundGut-Landmann, Salome; Hardt, Wolf-Dietrich

    2016-06-01

    Salmonella Typhimurium (S.Tm) is a common cause of self-limiting diarrhea. The mucosal inflammation is thought to arise from a standoff between the pathogen's virulence factors and the host's mucosal innate immune defenses, particularly the mucosal NAIP/NLRC4 inflammasome. However, it had remained unclear how this switches the gut from homeostasis to inflammation. This was studied using the streptomycin mouse model. S.Tm infections in knockout mice, cytokine inhibition and -injection experiments revealed that caspase-1 (not -11) dependent IL-18 is pivotal for inducing acute inflammation. IL-18 boosted NK cell chemoattractants and enhanced the NK cells' migratory capacity, thus promoting mucosal accumulation of mature, activated NK cells. NK cell depletion and Prf-/- ablation (but not granulocyte-depletion or T-cell deficiency) delayed tissue inflammation. Our data suggest an NK cell perforin response as one limiting factor in mounting gut mucosal inflammation. Thus, IL-18-elicited NK cell perforin responses seem to be critical for coordinating mucosal inflammation during early infection, when S.Tm strongly relies on virulence factors detectable by the inflammasome. This may have broad relevance for mucosal defense against microbial pathogens. PMID:27341123

  1. An NK Cell Perforin Response Elicited via IL-18 Controls Mucosal Inflammation Kinetics during Salmonella Gut Infection

    PubMed Central

    Müller, Anna A.; Dolowschiak, Tamas; Sellin, Mikael E.; Felmy, Boas; Verbree, Carolin; Gadient, Sandra; Westermann, Alexander J.; Vogel, Jörg; LeibundGut-Landmann, Salome; Hardt, Wolf-Dietrich

    2016-01-01

    Salmonella Typhimurium (S.Tm) is a common cause of self-limiting diarrhea. The mucosal inflammation is thought to arise from a standoff between the pathogen's virulence factors and the host's mucosal innate immune defenses, particularly the mucosal NAIP/NLRC4 inflammasome. However, it had remained unclear how this switches the gut from homeostasis to inflammation. This was studied using the streptomycin mouse model. S.Tm infections in knockout mice, cytokine inhibition and –injection experiments revealed that caspase-1 (not -11) dependent IL-18 is pivotal for inducing acute inflammation. IL-18 boosted NK cell chemoattractants and enhanced the NK cells' migratory capacity, thus promoting mucosal accumulation of mature, activated NK cells. NK cell depletion and Prf-/- ablation (but not granulocyte-depletion or T-cell deficiency) delayed tissue inflammation. Our data suggest an NK cell perforin response as one limiting factor in mounting gut mucosal inflammation. Thus, IL-18-elicited NK cell perforin responses seem to be critical for coordinating mucosal inflammation during early infection, when S.Tm strongly relies on virulence factors detectable by the inflammasome. This may have broad relevance for mucosal defense against microbial pathogens. PMID:27341123

  2. Respiratory mucosal permeability in asthma

    SciTech Connect

    Elwood, R.K.; Kennedy, S.; Belzberg, A.; Hogg, J.C.; Pare, P.D.

    1983-09-01

    The permeability of respiratory mucosa to technetium-labeled diethylenetriamine pentacetic acid (/sup 99m/Tc-DTPA) was measured in 10 clinically stable chronic asthmatics and the results were compared with those in 9 nonasthmatic control subjects. Nonspecific bronchial reactivity was measured using methacholine, and the PC20 was calculated. The intrapulmonary distribution and dose of the inhaled /sup 99m/Tc-DTPA was determined by a gamma camera and the half-life of the aerosolized label in the lung was calculated. The accumulation of radioactivity in the blood was monitored and a permeability index was calculated at 10, 25, and 60 min after aerosolization. Despite marked differences in airway reactivity, no differences in either parameter of permeability could be detected between the asthmatics and the control group. It is concluded that clinically stable asthmatics do not demonstrate increase mucosal permeability to small solutes when compared with normal subjects.

  3. Treatment of oral mucositis due to chemotherapy

    PubMed Central

    Bagán-Sebastián, José V

    2016-01-01

    Introduction The management of oral mucositis is a challenge, due to its complex biological nature. Over the last 10 years, different strategies have been developed for the management of oral mucositis caused by chemotherapy in cancer patients. Material and Methods An exhaustive search was made of the PubMed-Medline, Cochrane Library and Scopus databases, crossing the key words “oral mucositis”, “prevention” and “treatment” with the terms “chemotherapy” and “radiotherapy” by means of the boolean operators “AND” and “NOT”. A total of 268 articles were obtained, of which 96 met the inclusion criteria. Results Several interventions for the prevention of oral mucositis, such as oral hygiene protocols, amifostine, benzidamine, calcium phosphate, cryotherapy and iseganan, among others, were found to yield only limited benefits. Other studies have reported a decrease in the appearance and severity of mucositis with the use of cytoprotectors (sucralfate, oral glutamine, hyaluronic acid), growth factors, topical polyvinylpyrrolidone, and low power laser irradiation. Conclusions Very few interventions of confirmed efficacy are available for the management of oral mucositis due to chemotherapy. However, according to the reviewed literature, the use of palifermin, cryotherapy and low power laser offers benefits, reducing the incidence and severity of oral mucositis – though further studies are needed to confirm the results obtained. Key words:Chemotherapy-Induced Oral Mucositis Treatment. PMID:27034762

  4. Hepatitis E: Molecular Virology and Pathogenesis

    PubMed Central

    Panda, Subrat K.; Varma, Satya P.K.

    2013-01-01

    Hepatitis E virus is a single, positive-sense, capped and poly A tailed RNA virus classified under the family Hepeviridae. Enteric transmission, acute self-limiting hepatitis, frequent epidemic and sporadic occurrence, high mortality in affected pregnants are hallmarks of hepatitis E infection. Lack of an efficient culture system and resulting reductionist approaches for the study of replication and pathogenesis of HEV made it to be a less understood agent. Early studies on animal models, sub-genomic expression of open reading frames (ORF) and infectious cDNA clones have helped in elucidating the genome organization, important stages in HEV replication and pathogenesis. The genome contains three ORF's and three untranslated regions (UTR). The 5′ distal ORF, ORF1 is translated by host ribosomes in a cap dependent manner to form the non-structural polyprotein including the viral replicase. HEV replicates via a negative-sense RNA intermediate which helps in the formation of the positive-sense genomic RNA and a single bi-cistronic sub-genomic RNA. The 3′ distal ORF's including the major structural protein pORF2 and the multifunctional host interacting protein pORF3 are translated from the sub-genomic RNA. Pathogenesis in HEV infections is not well articulated, and remains a concern due to the many aspects like host dependent and genotype specific variations. Animal HEV, zoonosis, chronicity in immunosuppressed patients, and rapid decompensation in affected chronic liver diseased patients warrants detailed investigation of the underlying pathogenesis. Recent advances about structure, entry, egress and functional characterization of ORF1 domains has furthered our understanding about HEV. This article is an effort to review our present understanding about molecular biology and pathogenesis of HEV. PMID:25755485

  5. The mucosal immune system for vaccine development.

    PubMed

    Lamichhane, Aayam; Azegamia, Tatsuhiko; Kiyonoa, Hiroshi

    2014-11-20

    Mucosal surfaces are continuously exposed to the external environment and therefore represent the largest lymphoid organ of the body. In the mucosal immune system, gut-associated lymphoid tissues (GALTs), including Peyer's patches and isolated lymphoid follicles, play an important role in the induction of antigen-specific immune responses in the gut. GALTs have unique organogenesis characteristics and interact with the network of dendritic cells and T cells for the simultaneous induction and regulation of IgA responses and oral tolerance. In these lymphoid tissues, antigens are up taken by M cells in the epithelial layer, and antigen-specific immune responses are subsequently initiated by GALT cells. Nasopharynx- and tear-duct-associated lymphoid tissues (NALTs and TALTs) are key organized lymphoid structures in the respiratory tract and ocular cavities, respectively, and have been shown to interact with each other. Mucosal surfaces are also characterized by host-microbe interactions that affect the genesis and maturation of mucosa-associated lymphoid tissues and the induction and regulation of innate and acquired mucosal immune responses. Because most harmful pathogens enter the body through mucosal surfaces by ingestion, inhalation, or sexual contact, the mucosa is a candidate site for vaccination. Mucosal vaccination has some physiological and practical advantages, such as decreased costs and reduced risk of needle-stick injuries and transmission of bloodborne diseases, and it is painless. Recently, the application of modern bioengineering and biochemical engineering technologies, including gene transformation and manipulation systems, resulted in the development of systems to express vaccine antigens in transgenic plants and nanogels, which will usher in a new era of delivery systems for mucosal vaccine antigens. In this review, based on some of our research group's thirty seven years of progress and effort, we highlight the unique features of mucosal immune

  6. Sinusitis (acute)

    PubMed Central

    2008-01-01

    Introduction Acute sinusitis is defined pathologically, by transient inflammation of the mucosal lining of the paranasal sinuses lasting less than 4 weeks. Clinically, it is characterised by nasal congestion, rhinorrhoea, facial pain, hyposmia, sneezing, and, if more severe, additional malaise and fever. It affects 1−5% of the adult population each year in Europe. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments in people with clinically diagnosed acute sinusitis, and with radiologically or bacteriologically confirmed acute sinusitis? We searched: Medline, Embase, The Cochrane Library and other important databases up to August 2007 (BMJ Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 19 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotics (amoxicillin, co-amoxiclav, doxycycline, cephalosporins, macrolides, different doses [amoxicillin, co-amoxiclav, doxycycline, cephalosporins, macrolides], long-course regimens), antihistamines, cephalosporins or macrolides, decongestants (xylometazoline, phenylephrine, pseudoephedrine), doxycycline, saline nasal washes, steam inhalation, and topical corticosteroids (intra-nasal). PMID:19450327

  7. Sinusitis (acute)

    PubMed Central

    2011-01-01

    Introduction Acute sinusitis is defined pathologically, by transient inflammation of the mucosal lining of the paranasal sinuses lasting less than 4 weeks. Clinically, it is characterised by nasal congestion, rhinorrhoea, facial pain, hyposmia, sneezing, and, if more severe, additional malaise and fever. It affects 1% to 5% of the adult population each year in Europe. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments in people with clinically diagnosed acute sinusitis, and in people with radiologically or bacteriologically confirmed acute sinusitis? We searched: Medline, Embase, The Cochrane Library, and other important databases up to June 2011 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found 19 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review we present information relating to the effectiveness and safety of the following interventions: antibiotics (amoxicillin, amoxicillin–clavulanic acid [co-amoxiclav], doxycycline, cephalosporins, macrolides; different doses, long-course regimens), antihistamines, decongestants (xylometazoline, phenylephrine, pseudoephedrine), saline nasal washes, steam inhalation, and topical corticosteroids (intranasal). PMID:22189346

  8. Imbalanced secondary mucosal antioxidant response in inflammatory bowel disease.

    PubMed

    Kruidenier, Laurens; Kuiper, Ineke; Van Duijn, Wim; Mieremet-Ooms, Marij A C; van Hogezand, Ruud A; Lamers, Cornelis B H W; Verspaget, Hein W

    2003-09-01

    Intestinal mucosal damage in the inflammatory bowel diseases (IBD) Crohn's disease (CD) and ulcerative colitis (UC) involves reactive oxygen metabolites (ROMs). ROMs are neutralized by endogenous antioxidant enzymes in a carefully balanced two-step pathway. Superoxide dismutases (SODs) convert superoxide anion to hydrogen peroxide (H(2)O(2)), which is subsequently neutralized to water by catalase (CAT) or glutathione peroxidase (GPO). Remarkably changed expression levels of the three isoforms of SOD in paired non-inflamed and inflamed mucosae from CD and UC patients have been previously reported in comparison to normal control mucosa. Most notable was the strong up-regulation of Mn-SOD in inflamed epithelium. It was hypothesized that in order to provide optimal protection against ROM-mediated damage, these changes should be coordinately counterbalanced by an increased H(2)O(2)-neutralizing capacity. Therefore, the same tissue samples were used to assess the levels, activities, and/or localization of the most prominent mucosal H(2)O(2)-related antioxidants CAT, GPO, glutathione (GSH), myeloperoxidase (MPO), and metallothionein (MT). Quantitative measurements showed that in both CD and UC patients, intestinal inflammation was associated with increased activities of CAT, GPO, and MPO, whereas the mucosal GSH content was unaffected and the concentration of MT was decreased. Despite this overall increase in mucosal H(2)O(2)-metabolizing enzyme capacity, immunohistochemical analysis revealed a differentially disturbed antioxidant balance in IBD epithelium and lamina propria. In the lamina propria, the risk of direct H(2)O(2)-mediated damage seemed to be restrained by the increasing numbers of CAT- and MPO-positive monocytes/macrophages and neutrophils that infiltrated the inflamed areas. On the other hand, MPO overexpression might increase the lamina propria levels of hypochlorous acid, a stable ROM with multiple pro-inflammatory effects. In the epithelium, the number of

  9. Perinatal Asphyxia I: Pathogenesis of Multisystemic Sequelae

    PubMed Central

    Fomufod, Antoine K.; Rahbar, Fariborz; White, Penny L.; Holloway, Albert Z.; Rampersaud, Swami R.; Henry, Lionel A.

    1979-01-01

    This paper describes the clinical and pathologic sequelae of perinatal asphyxia manifested by 17 neonates treated at Howard University Hospital over an 18-month period. Multiple systemic complications, occurring in 76.5 percent of the patients, were the rule rather than the exception. All vital organs were involved, singly or in combination. Understanding the pathogenesis and extent of these complications is of utmost importance not only to those rendering health care to acutely ill newborns, but also to those responsible for prenatal and maternal intrapartum care. PMID:537116

  10. Palliation of radiation-related mucositis

    SciTech Connect

    Rothwell, B.R.; Spektor, W.S.

    1990-01-01

    Oral mucositis associated with head and neck radiotherapy can substantially hinder completion of cancer therapy. Alleviation of this often severe stomatitis can provide enhanced patient comfort and facilitate appropriate care. A double-blind format was used in a pilot project to measure, against a control rinse, the effectiveness of an oral rinse consisting of hydrocortisone, nystatin, tetracycline, and diphenhydramine in controlling radiation-related mucositis. A combination of clinical evaluation and patient responses to a questionnaire was used to judge the results of the topical medications. Patients using the experimental medication developed less mucositis than did patients in the control group.

  11. Oral mucositis. A complication of radiotherapy

    SciTech Connect

    Rider, C.A. )

    1990-11-01

    Oral mucositis is a complication of head and neck radiotherapy. It is understood what causes the inflammation and what biological tissue changes occur, however, a definite cure for oral mucositis has not yet been found. Supportive treatments, analgesics, antimicrobials and anti-inflammatory agents have been prescribed, none of which has been a thorough measure of treatment. An effective cure for oral mucositis is still in the midst of scientific research. In the interim local palliative treatments will help to alleviate the patients', debilitating symptoms.

  12. Pathogenesis of Necrotizing Enterocolitis

    PubMed Central

    Tanner, Scott M.; Berryhill, Taylor F.; Ellenburg, James L.; Jilling, Tamas; Cleveland, Dava S.; Lorenz, Robin G.; Martin, Colin A.

    2016-01-01

    Necrotizing enterocolitis (NEC) is a major cause of morbidity and mortality in premature infants. The pathophysiology is likely secondary to innate immune responses to intestinal microbiota by the premature infant's intestinal tract, leading to inflammation and injury. This review provides an updated summary of the components of the innate immune system involved in NEC pathogenesis. In addition, we evaluate the animal models that have been used to study NEC with regard to the involvement of innate immune factors and histopathological changes as compared to those seen in infants with NEC. Finally, we discuss new approaches to studying NEC, including mathematical models of intestinal injury and the use of humanized mice. PMID:25447054

  13. Complement and Viral Pathogenesis

    PubMed Central

    Stoermer, Kristina A.; Morrison, Thomas E.

    2011-01-01

    The complement system functions as an immune surveillance system that rapidly responds to infection. Activation of the complement system by specific recognition pathways triggers a protease cascade, generating cleavage products that function to eliminate pathogens, regulate inflammatory responses, and shape adaptive immune responses. However, when dysregulated, these powerful functions can become destructive and the complement system has been implicated as a pathogenic effector in numerous diseases, including infectious diseases. This review highlights recent discoveries that have identified critical roles for the complement system in the pathogenesis of viral infection. PMID:21292294

  14. The Pathogenesis and Immunobiology of Mousepox.

    PubMed

    Sigal, Luis J

    2016-01-01

    Ectromelia virus is a mouse-specific orthopoxvirus that, following footpad infection or natural transmission, causes mousepox in most strains of mice, while a few strains, such as C57BL/6, are resistant to the disease but not to the infection. Mousepox is an acute, systemic, highly lethal disease of remarkable semblance to smallpox, caused by the human-specific variola virus. Starting in 1929 with its discovery by Marchal, work with ECTV has provided essential information for our current understanding on how viruses spread lympho-hematogenously, the genetic control of antiviral resistance, the role of different components of the innate and adaptive immune system in the control of primary and secondary infections with acute viruses, and how the mechanisms of immune evasion deployed by the virus affect virulence in vivo. Here, I review the literature on the pathogenesis and immunobiology of ECTV infection in vivo. PMID:26791861

  15. Tissular senescence and modifications of oral ecosystem in the elderly: risk factors for mucosal pathologies.

    PubMed

    Bodineau, Agnès; Folliguet, Marysette; Séguier, Sylvie

    2009-07-01

    The aim of this present review is to describe the pathogenesis and mechanisms behind mucosal pathologies in the elderly including a description of the risk factors for these pathologies. The oral cavity - and particularly oral mucosae - is exposed to many stresses as well as physical, chemical, thermic and pathogenic agents. In the elderly, mucosae are less resistant to the insults, and this increases the occurrence of diseases. Several factors contribute to the prevalence of mucosal pathologies with aging. There are two categories: intrinsic factors linked to the senescence of the tissues and functions, and extrinsic factors related to the older people general health status. The intrinsic factors are: 1) mucosal senescence which induces fragility 2) immunosenescence which causes a decrease in the host response against micro-organisms and an increase in the autoimmune diseases and 3) senescence of salivary glands and reduction of the saliva protective function. Furthermore, there are extrinsic factors which contribute to change the oral ecosystem during aging, such as polypathologies and polymedications, malnutrition, degradation of oral hygiene, pathogen proliferation (mainly bacteria and Candida species) and old or ill-fitted removable dentures. In the elderly several diseases occur on the oral mucosae: inflammation, bacterial infections or candidiasis, ulcerations, autoimmune dermatosis, tumoral processes. This review describes some common oral mucosal pathologies in the older people, which illustrate the impact of different risk factors described in the first part. PMID:20021405

  16. Inflammatory Bowel Disease: Autoimmune or Immune-mediated Pathogenesis?

    PubMed Central

    Wen, Zhonghui

    2004-01-01

    The pathogenesis of Crohn's disease (CD) and ulcerative colitis (UC), the two main forms of inflammatory bowel disease (IBD), is still unclear, but both autoimmune and immune-mediated phenomena are involved. Autoimmune phenomena include the presence of serum and mucosal autoantibodies against intestinal epithelial cells in either form of IBD, and against human tropomyosin fraction five selectively in UC. In addition, perinuclear antineutrophil cytoplasmic antibodies (pANCA) are common in UC, whereas antibodies against Saccharomyces cerevisiae (ASCA) are frequently found in CD. Immune-mediate phenomena include a variety of abnormalities of humoral and cell-mediated immunity, and a generalized enhanced reactivity against intestinal bacterial antigens in both CD and UC. It is currently believed that loss of tolerance against the indigenous enteric flora is the central event in IBD pathogenesis. Various complementary factors probably contribute to the loss of tolerance to commensal bacteria in IBD. They include defects in regulatory T-cell function, excessive stimulation of mucosal dendritic cells, infections or variants of proteins critically involved in bacterial antigen recognition, such as the products of CD-associated NOD2/CARD15 mutations. PMID:15559364

  17. Pathogenesis of Arrhythmogenic Cardiomyopathy.

    PubMed

    Asimaki, Angeliki; Kleber, Andre G; Saffitz, Jeffrey E

    2015-11-01

    Arrhythmogenic cardiomyopathy (ACM) is a primary myocardial disease. It is characterized by frequent ventricular arrhythmias and increased risk of sudden cardiac death typically arising as an early manifestation before the onset of significant myocardial remodelling. Myocardial degeneration, often confined to the right ventricular free wall, with replacement by fibrofatty scar tissue, develops in many patients. ACM is a familial disease but genetic penetrance can be low and disease expression is highly variable. Inflammation might promote disease progression. It also appears that exercise increases disease penetrance and accelerates its development. More than 60% of probands harbour mutations in genes that encode desmosomal proteins, which has raised the possibility that defective cell-cell adhesion might play a role in disease pathogenesis. Recent advances have implicated changes in the canonical wingless-type mouse mammary tumour virus integration site (Wnt)/β-catenin and Hippo signalling pathways and defects in forwarding trafficking of ion channels and other proteins to the intercalated disk in cardiac myocytes. In this review we summarize the current understanding of the pathogenesis of ACM and highlight future research directions. PMID:26199027

  18. Update on mucormycosis pathogenesis

    PubMed Central

    Ibrahim, Ashraf S.; Kontoyiannis, Dimitrios P.

    2014-01-01

    Purpose of review Mucormycosis is an increasingly common fungal infection with unacceptably high mortality. The recent sequencing genome projects of Mucorales and the development of gene manipulation have enabled significant advances in understanding the pathogenesis of mucormycosis. Therefore, we review the pathogenesis of mucormycosis and highlight potential development of novel diagnostic and therapeutic modalities against this lethal disease. Recent findings Much of the work has been focused on the role of iron uptake in the virulence of Mucorales. Additionally, host receptors and fungal ligands involved in the process of tissue invasion as well as sporangiospore size and sex loci and their contribution to virulence of Mucorales are discussed. Finally, the role of innate and adaptive immunity in protection against Mucorales and new evidence about drug-induced apoptosis in these fungi are discussed. Summary Recent discoveries introduce several potentially novel diagnostic and therapeutic modalities, which are likely to improve management and outcome for mucormycosis. Future preclinical and clinical research is warranted to develop these diagnostic and therapeutic strategies. PMID:24126718

  19. Mucosal barrier, bacteria and inflammatory bowel disease: possibilities for therapy.

    PubMed

    Merga, Yvette; Campbell, Barry J; Rhodes, Jonathan M

    2014-01-01

    The mucosal barrier has three major components, the mucus layer, the epithelial glycocalyx and the surface epithelium itself, whose integrity largely depends on tight junction function. In health, there is relatively little direct interaction between the luminal microbiota and the epithelium - the continuous mucus layer in the colon keeps the surface epithelium out of contact with bacteria and the ileo-caecal valve ensures that the distal small intestine is relatively microbe free. Most interaction takes place at the Peyer's patches in the distal ileum and their smaller colonic equivalents, the lymphoid follicles. Peyer's patches are overlain by a 'dome' epithelium, 5% of whose cells are specialised M (microfold) epithelial cells, which act as the major portal of entry for bacteria. There are no goblet cells in the dome epithelium and M cells have a very sparse glycocalyx allowing easy microbial interaction. It is intriguing that the typical age range for the onset of Crohn's disease (CD) is similar to the age at which the number of Peyer's patches is greatest. Peyer's patches are commonly the sites of the initial lesions in CD and the 'anti-pancreatic' antibody associated with CD has been shown to have as its epitope the glycoprotein 2 that is the receptor for type-1 bacterial fimbrial protein (fimH) on M cells. There are many reasons to believe that the mucosal barrier is critically important in the pathogenesis of inflammatory bowel disease (IBD). These include (i) associations between both CD and ulcerative colitis (UC) with genes that are relevant to the mucosal barrier; (ii) increased intestinal permeability in unaffected relatives of CD patients; (iii) increased immune reactivity against bacterial antigens, and (iv) animal models in which altered mucosal barrier, e.g. denudation of the mucus layer associated with oral dextran sulphate in rodents, induces colitis. Whilst some IBD patients may have genetic factors leading to weakening of the mucosal barrier

  20. Microbiota and Mucosal Immunity in Amphibians

    PubMed Central

    Colombo, Bruno M.; Scalvenzi, Thibault; Benlamara, Sarah; Pollet, Nicolas

    2015-01-01

    We know that animals live in a world dominated by bacteria. In the last 20 years, we have learned that microbes are essential regulators of mucosal immunity. Bacteria, archeas, and viruses influence different aspects of mucosal development and function. Yet, the literature mainly covers findings obtained in mammals. In this review, we focus on two major themes that emerge from the comparative analysis of mammals and amphibians. These themes concern: (i) the structure and functions of lymphoid organs and immune cells in amphibians, with a focus on the gut mucosal immune system; and (ii) the characteristics of the amphibian microbiota and its influence on mucosal immunity. Lastly, we propose to use Xenopus tadpoles as an alternative small-animal model to improve the fundamental knowledge on immunological functions of gut microbiota. PMID:25821449

  1. Exploiting Mucosal Immunity for Antiviral Vaccines.

    PubMed

    Iwasaki, Akiko

    2016-05-20

    Mucosal surfaces provide a remarkably effective barrier against potentially dangerous pathogens. Therefore, enhancing mucosal immunity through vaccines-strengthening that first line of defense-holds significant promise for reducing the burden of viral diseases. The large and varied class of viral pathogens, however, continues to present thorny challenges to vaccine development. Two primary difficulties exist: Viruses exhibit a stunning diversity of strategies for evading the host immune response, and even when we understand the nature of effective immune protection against a given virus, eliciting that protection is technically challenging. Only a few mucosal vaccines have surmounted these obstacles thus far. Recent developments, however, could greatly improve vaccine design. In this review, we first sketch out our understanding of mucosal immunity and then compare the herpes simplex virus, human immunodeficiency virus, and influenza virus to illustrate the distinct challenges of developing successful vaccines and to outline potential solutions. PMID:27168245

  2. Efficiency of Cell-Free and Cell-Associated Virus in Mucosal Transmission of Human Immunodeficiency Virus Type 1 and Simian Immunodeficiency Virus

    PubMed Central

    Hulot, Sandrine L.; Korioth-Schmitz, Birgit; Gombos, Randi B.; Zheng, Yi; Owuor, Joshua; Lifton, Michelle A.; Ayeni, Christian; Najarian, Robert M.; Yeh, Wendy W.; Asmal, Mohammed; Zamir, Gideon; Letvin, Norman L.

    2013-01-01

    Effective strategies are needed to block mucosal transmission of human immunodeficiency virus type 1 (HIV-1). Here, we address a crucial question in HIV-1 pathogenesis: whether infected donor mononuclear cells or cell-free virus plays the more important role in initiating mucosal infection by HIV-1. This distinction is critical, as effective strategies for blocking cell-free and cell-associated virus transmission may be different. We describe a novel ex vivo model system that utilizes sealed human colonic mucosa explants and demonstrate in both the ex vivo model and in vivo using the rectal challenge model in rhesus monkeys that HIV-1-infected lymphocytes can transmit infection across the mucosa more efficiently than cell-free virus. These findings may have significant implications for our understanding of the pathogenesis of mucosal transmission of HIV-1 and for the development of strategies to prevent HIV-1 transmission. PMID:24109227

  3. Localized Pemphigus Vegetans without Mucosal Involvement

    PubMed Central

    Jain, VK; Jindal, N; Imchen, S

    2014-01-01

    Pemphigus vegetans is a rare variant of pemphigus vulgaris. A 62-year-old woman presented with erythematous moist vegetative plaque on the left breast and left groin. There was no mucosal involvement. Histopathological and direct immunofluorescence findings were suggestive of pemphigus vegetans. She showed excellent response to oral steroids. Literature is scarcely available on the limited involvement with pemphigus vegetans without mucosal involvement. PMID:24700958

  4. Intestinal inflammation and mucosal barrier function.

    PubMed

    Sánchez de Medina, Fermín; Romero-Calvo, Isabel; Mascaraque, Cristina; Martínez-Augustin, Olga

    2014-12-01

    Intestinal mucosal barrier function is the capacity of the intestine to provide adequate containment of luminal microorganisms and molecules while preserving the ability to absorb nutrients. The central element is the epithelial layer, which physically separates the lumen and the internal milieu and is in charge of vectorial transport of ions, nutrients, and other substances. The secretion of mucus-forming mucins, sIgA, and antimicrobial peptides reinforces the mucosal barrier on the extraepithelial side, while a variety of immune cells contributes to mucosal defense in the inner side. Thus, the mucosal barrier is of physical, biochemical, and immune nature. In addition, the microbiota may be viewed as part of this system because of the mutual influence occurring between the host and the luminal microorganisms. Alteration of the mucosal barrier function with accompanying increased permeability and/or bacterial translocation has been linked with a variety of conditions, including inflammatory bowel disease. Genetic and environmental factors may converge to evoke a defective function of the barrier, which in turn may lead to overt inflammation of the intestine as a result of an exacerbated immune reaction toward the microbiota. According to this hypothesis, inflammatory bowel disease may be both precipitated and treated by either stimulation or downregulation of the different elements of the mucosal barrier, with the outcome depending on timing, the cell type affected, and other factors. In this review, we cover briefly the elements of the barrier and their involvement in functional defects and the resulting phenotype. PMID:25222662

  5. Role of bombesin on gut mucosal growth.

    PubMed Central

    Chu, K U; Evers, B M; Ishizuka, J; Townsend, C M; Thompson, J C

    1995-01-01

    OBJECTIVE: The authors examined the effects of exogenous bombesin (BBS) on gut mucosal growth in chow-fed rats and the mucosal regeneration after gut atrophy brought about by feeding an elemental diet and after intestinal injury produced by methotrexate (MTX). SUMMARY BACKGROUND DATA: Bombesin is one of many gastrointestinal peptides implicated in the regulation of gut mucosal growth. Although BBS is known to stimulate growth of normal pancreatic tissue, the trophic effect of BBS on gut mucosa is less clear and its exact role in gut mucosal regeneration and repair is not known. METHODS: Rats were fed a regular chow diet (control) or an elemental diet plus either saline or BBS (10 micrograms/kg). In another experiment, rats fed a chow diet and treated with saline or BBS were given MTX (20 micrograms/kg) or a single intraperitoneal injection. In all experiments, small and large bowel mucosa and pancreas were removed and analyzed for BBS-mediated proliferation. RESULTS: Bombesin produced significant mucosal proliferation of the small bowel at day 14, but not at day 7, in rats fed regular chow. In contrast, BBS treatment for 7 days produced significant proliferation in both the atrophic and injured gut mucosa of rats given elemental diet or MTX. CONCLUSIONS: Bombesin may be an important enterotrophic factor for normal mucosal proliferation and may be clinically beneficial as an agent to restore or maintain gut mucosa during periods of atrophy or injury. PMID:7618976

  6. Gut Mucosal FOXP3+ Regulatory CD4+ T Cells and Nonregulatory CD4+ T Cells Are Differentially Affected by Simian Immunodeficiency Virus Infection in Rhesus Macaques▿

    PubMed Central

    Allers, Kristina; Loddenkemper, Christoph; Hofmann, Jörg; Unbehaun, Anett; Kunkel, Désirée; Moos, Verena; Kaup, Franz-Josef; Stahl-Hennig, Christiane; Sauermann, Ulrike; Epple, Hans-Jörg; Schneider, Thomas

    2010-01-01

    The gastrointestinal tract represents a major site for human and simian immunodeficiency virus (HIV and SIV) replication and CD4+ T-cell depletion. Despite severe depletion of mucosal CD4+ T cells, FOXP3+ regulatory CD4+ T cells (Treg) are highly increased in the gut mucosa of chronically HIV-infected individuals and may contribute to HIV pathogenesis, either by their immunosuppressive function or as a significant target cell population for virus production. Little is known about the susceptibility of mucosal Treg to viral infection and the longitudinal effect of HIV/SIV infection on Treg dynamics. In this study, we determined the level of SIV infection in Treg and nonregulatory CD4+ T cells (non-Treg) isolated from the colon of SIV-infected rhesus macaques. The dynamics of mucosal Treg and alterations in the mucosal CD4+ T-cell pool were examined longitudinally. Our findings indicate that mucosal Treg were less susceptible to productive SIV infection than non-Treg and thus were selectively spared from SIV-mediated cell death. In addition to improved survival, local expansion of Treg by SIV-induced proliferation of the mucosal CD4+ T-cell pool facilitated the accumulation of mucosal Treg during the course of infection. High frequency of mucosal Treg in chronic SIV infection was strongly related to a reduction of perforin-expressing cells. In conclusion, this study suggests that mucosal Treg are less affected by productive SIV infection than non-Treg and therefore spared from depletion. Although SIV production is limited in mucosal Treg, Treg accumulation may indirectly contribute to viral persistence by suppressing antiviral immune responses. PMID:20071575

  7. Fungal Aflatoxins Reduce Respiratory Mucosal Ciliary Function.

    PubMed

    Lee, Robert J; Workman, Alan D; Carey, Ryan M; Chen, Bei; Rosen, Phillip L; Doghramji, Laurel; Adappa, Nithin D; Palmer, James N; Kennedy, David W; Cohen, Noam A

    2016-01-01

    Aflatoxins are mycotoxins secreted by Aspergillus flavus, which can colonize the respiratory tract and cause fungal rhinosinusitis or bronchopulmonary aspergillosis. A. flavus is the second leading cause of invasive aspergillosis worldwide. Because many respiratory pathogens secrete toxins to impair mucociliary immunity, we examined the effects of acute exposure to aflatoxins on airway cell physiology. Using air-liquid interface cultures of primary human sinonasal and bronchial cells, we imaged ciliary beat frequency (CBF), intracellular calcium, and nitric oxide (NO). Exposure to aflatoxins (0.1 to 10 μM; 5 to 10 minutes) reduced baseline (~6-12%) and agonist-stimulated CBF. Conditioned media (CM) from A. fumigatus, A. niger, and A. flavus cultures also reduced CBF by ~10% after 60 min exposure, but effects were blocked by an anti-aflatoxin antibody only with A. flavus CM. CBF reduction required protein kinase C but was not associated with changes in calcium or NO. However, AFB2 reduced NO production by ~50% during stimulation of the ciliary-localized T2R38 receptor. Using a fluorescent reporter construct expressed in A549 cells, we directly observed activation of PKC activity by AFB2. Aflatoxins secreted by respiratory A. flavus may impair motile and chemosensory functions of airway cilia, contributing to pathogenesis of fungal airway diseases. PMID:27623953

  8. Pathogenesis of Group A Streptococcal Infections

    PubMed Central

    Cunningham, Madeleine W.

    2000-01-01

    Group A streptococci are model extracellular gram-positive pathogens responsible for pharyngitis, impetigo, rheumatic fever, and acute glomerulonephritis. A resurgence of invasive streptococcal diseases and rheumatic fever has appeared in outbreaks over the past 10 years, with a predominant M1 serotype as well as others identified with the outbreaks. emm (M protein) gene sequencing has changed serotyping, and new virulence genes and new virulence regulatory networks have been defined. The emm gene superfamily has expanded to include antiphagocytic molecules and immunoglobulin-binding proteins with common structural features. At least nine superantigens have been characterized, all of which may contribute to toxic streptococcal syndrome. An emerging theme is the dichotomy between skin and throat strains in their epidemiology and genetic makeup. Eleven adhesins have been reported, and surface plasmin-binding proteins have been defined. The strong resistance of the group A streptococcus to phagocytosis is related to factor H and fibrinogen binding by M protein and to disarming complement component C5a by the C5a peptidase. Molecular mimicry appears to play a role in autoimmune mechanisms involved in rheumatic fever, while nephritis strain-associated proteins may lead to immune-mediated acute glomerulonephritis. Vaccine strategies have focused on recombinant M protein and C5a peptidase vaccines, and mucosal vaccine delivery systems are under investigation. PMID:10885988

  9. Microbial pathogenesis meets biomechanics.

    PubMed

    Charles-Orszag, Arthur; Lemichez, Emmanuel; Tran Van Nhieu, Guy; Duménil, Guillaume

    2016-02-01

    Introducing concepts from soft matter physics and mechanics has largely contributed to our understanding of a variety of biological processes. In this review, we argue that this holds true for bacterial pathogenesis. We base this argument on three examples of bacterial pathogens and their interaction with host cells during infection: (i) Shigella flexneri exploits actin-dependent forces to come into close contact with epithelial cells prior to invasion of the epithelium; (ii) Neisseria meningitidis manipulates endothelial cells to resist shear stress during vascular colonization; (iii) bacterial toxins take advantage of the biophysical properties of the host cell plasma membrane to generate transcellular macroapertures in the vascular wall. Together, these examples show that a multidisciplinary approach integrating physics and biology is more necessary than ever to understand complex infectious phenomena. Moreover, this avenue of research will allow the exploration of general processes in cell biology, highlighted by pathogens, in the context of other non-communicable human diseases. PMID:26849533

  10. Molecular pathogenesis of emphysema

    PubMed Central

    Taraseviciene-Stewart, Laimute; Voelkel, Norbert F.

    2008-01-01

    Emphysema is one manifestation of a group of chronic, obstructive, and frequently progressive destructive lung diseases. Cigarette smoking and air pollution are the main causes of emphysema in humans, and cigarette smoking causes emphysema in rodents. This review examines the concept of a homeostatically active lung structure maintenance program that, when attacked by proteases and oxidants, leads to the loss of alveolar septal cells and airspace enlargement. Inflammatory and noninflammatory mechanisms of disease pathogenesis, as well as the role of the innate and adaptive immune systems, are being explored in genetically altered animals and in exposure models of this disease. These recent scientific advances support a model whereby alveolar destruction resulting from a coalescence of mechanical forces, such as hyperinflation, and more recently recognized cellular and molecular events, including apoptosis, cellular senescence, and failed lung tissue repair, produces the clinically recognized syndrome of emphysema. PMID:18246188