Passage of Microorganisms Through the Intestinal Wall Effect of Surgical Stress, Hydrocortisone and the Impairment of Normal Defense Mechanisms

Diarrheal episodes and diarrheal disease are often considered to be acute events of limited duration; a review of current literature indicates that this is not true. Diarrheal episodes caused by many bacteria, viruses, protozoans and other parasites cause alteration of intestinal structure and function. Consequences of such diarrhea-associated gut alterations include loss of normal defense mechanisms against secondary opportunistic pathogens and the ability to exclude macromolecules from systemic circulation. Additionally, loss of endogenous nutrients and malabsorption of essential nutrients result from diarrheal episodes; the consequences of such losses, even of a single essential nutrient, is compromised immune function, which predisposes to further infection. The net result of such events in some persons is long-term debilitating disease(s) such as allergy, autoimmune disorders and neoplasia.

Download Full-text

Effect of Oxymetazoline Nose Drops on Acute Sinusitis in the Rabbit

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348949610500309 ◽

1996 ◽

Vol 105 (3) ◽

pp. 222-225 ◽

Cited By ~ 24

Author(s):

Mats Bende ◽

Masaya Fukami ◽

Karl E. Arfors ◽

Joakim Mark ◽

Pontus Sterna ◽

...

Keyword(s):

Blood Flow ◽

Defense Mechanisms ◽

Mucosal Blood Flow ◽

The Other ◽

Nasal Decongestant ◽

Inflammatory Score ◽

The Common ◽

Acute Rhinitis ◽

Maxillary Sinuses ◽

Normal Defense

This investigation was designed to evaluate the effect of the common topical nasal decongestant oxymetazoline hydrochloride on the early local tissue defense in an experimental bacterial infection. For that purpose, a bilateral infection of the maxillary sinus was induced in 14 rabbits. Nose drops (oxymetazoline) were instilled in one nasal cavity, and placebo in the other. After 48 hours, the degree of infection was judged by using a semiquantitative inflammatory score to evaluate histologic preparations of the maxillary sinuses. On the oxymetazoline-treated side, we found a significantly higher degree of inflammation. We conclude that oxymetazoline nose drops, commonly used in acute rhinitis and sinusitis, interfere with the normal defense mechanisms during bacterially induced sinusitis, possibly by a decrease in mucosal blood flow.

Download Full-text

Enteral insufficiency syndrome: current provisions about the terminology, pathogenesis and treatment (review of literature)

Grekov s Bulletin of Surgery ◽

10.24884/0042-4625-2020-179-6-101-106 ◽

2021 ◽

Vol 179 (6) ◽

pp. 101-106

Author(s):

S. A. Aliev ◽

E. S. Aliev

Keyword(s):

Defense Mechanisms ◽

Structural Changes ◽

Intestinal Wall ◽

Modern Concept ◽

Review Of Literature ◽

Pathogenetic Mechanisms ◽

Abdominal Organs ◽

Treatment Review ◽

Analytical Review ◽

Insufficiency Syndrome

An analytical review of the literature on the pathogenesis of disorders of the motor-evacuation function of the intestine, which underlies the enteral insufficiency syndrome (EIS), which develops in various acute intra-abdominal surgical diseases, is presented. On the basis of a multivariate analysis of literature data, various pathogenetic mechanisms of enteric dysfunctions caused by morphological and structural changes in the wall of the small intestine, violations of its local defense mechanisms are described. The essence of the modern concept of the pathogenesis of enteral insufficiency – enteral distress syndrome (EDS) according to the literature is presented. According to new views, EDS is a combination of various pathogenetic mechanisms that are formed as a result of dysregulation and destabilization of biological membranes of tissue structures of the intestinal wall (especially its mucous membrane) and a violation of the functional and metabolic status of the intestine, developing in acute surgical diseases of the abdominal organs. Recognition of the validity of the concept will allow unifying the terminology and creating more evidence-based and generally accepted teaching about the nature of EIS.

Download Full-text

Gut dysfunction in critically ill patients: a review of the literature

American Journal of Critical Care ◽

10.4037/ajcc1997.6.3.204 ◽

1997 ◽

Vol 6 (3) ◽

pp. 204-209 ◽

Cited By ~ 72

Author(s):

JK Stechmiller ◽

D Treloar ◽

N Allen

Keyword(s):

Critical Illness ◽

Enteral Nutrition ◽

Critically Ill ◽

Organ Dysfunction ◽

Critically Ill Patients ◽

Defense Mechanisms ◽

Multiple Organ ◽

Multiple Organ Dysfunction ◽

Gut Function ◽

Normal Defense

BACKGROUND: Critically ill patients are susceptible to injury of the intestinal mucosa, changes in gut permeability, and failure of intestinal defense mechanisms. These conditions put the patients at risk for infection and multiple organ dysfunction syndrome. Specific therapies are needed to prevent gut failure during critical illness. OBJECTIVE: The purpose of this literature review is to provide a better understanding of the normal defense mechanisms of the gut and alterations associated with ischemia-reperfusion injury, risk of infection, and the link to multiple organ dysfunction syndrome in critically ill patients. Implications for early enteral stimulation and nutrition are included. METHODS: Medical and nursing studies on the intestinal response to critical illness and on the implications for early enteral nutrition in critically ill patients were reviewed. RESULTS: Significant advances have been made in understanding the normal defense mechanisms of the gut, including barrier and immune functions. Translocation of bacteria, mediators of the inflammatory response, and the microcirculation play a role in the response to critical illness. Enteral nutrition that includes glutamine and arginine enhances gut function and improves patients' outcomes in some clinical states. DISCUSSION: Further research should focus on specific strategies to enhance gut function, prevent loss of gut integrity, and improve patients' outcomes. These strategies include maintaining mesenteric blood flow, using gastric tonometry to assess oxygenation, inhibiting inflammatory mediators, and using growth factors to modify the metabolic state in patients who are critically ill.

Download Full-text

Bacterial-Mucosal Cell Junctional Complexes

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050731 ◽

1974 ◽

Vol 32 ◽

pp. 144-145

Author(s):

Roger C. Wagner

Keyword(s):

Intestinal Wall ◽

Rat Colon ◽

Mucosal Cell ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Mucosal Cells ◽

Mucosal Lining ◽

Degenerative Alterations ◽

Junctional Complexes ◽

Intestinal Mucosal Cells

Bacteria exhibit the ability to adhere to the apical surfaces of intestinal mucosal cells. These attachments either precede invasion of the intestinal wall by the bacteria with accompanying inflammation and degeneration of the mucosa or represent permanent anchoring sites where the bacteria never totally penetrate the mucosal cells.Endemic gram negative bacteria were found attached to the surface of mucosal cells lining the walls of crypts in the rat colon. The bacteria did not intrude deeper than 0.5 urn into the mucosal cells and no degenerative alterations were detectable in the mucosal lining.

Download Full-text

New Ultrastructural Observations on Injury and Regeneration of Cilia in Mammalian Conducting Airway Epithelium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099544 ◽

1981 ◽

Vol 39 ◽

pp. 624-625

Author(s):

J.L. Carson ◽

A.M. Collier

Keyword(s):

Respiratory Tract ◽

Airway Epithelium ◽

Defense Mechanisms ◽

Normal Growth ◽

Fetal Lung ◽

Secretory Cells ◽

Airway Epithelial ◽

Ciliated Cells ◽

Conducting Airway ◽

Conducting Airways

The ciliated cells lining the conducting airways of mammals are integral to the defense mechanisms of the respiratory tract, functioning in coordination with secretory cells in the removal of inhaled and cellular debris. The effects of various infectious and toxic agents on the structure and function of airway epithelial cell cilia have been studied in our laboratory, both of which have been shown to affect ciliary ultrastructure.These observations have led to questions about ciliary regeneration as well as the possible induction of ciliogenesis in response to cellular injury. Classical models of ciliogenesis in the conducting airway epithelium of the mammalian respiratory tract have been based primarily on observations of the developing fetal lung. These observations provide a plausible explanation for the embryological generation of ciliary beds lining the conducting airways but do little to account for subsequent differentiation of ciliated cells and ciliogenesis during normal growth and development.

Download Full-text

Parasite defense mechanisms in bees: behavior, immunity, antimicrobials, and symbionts

Emerging Topics in Life Sciences ◽

10.1042/etls20190069 ◽

2019 ◽

Vol 4 (1) ◽

pp. 59-76 ◽

Cited By ~ 2

Author(s):

Alison E. Fowler ◽

Rebecca E. Irwin ◽

Lynn S. Adler

Keyword(s):

Defense Mechanisms ◽

Poor Quality ◽

Future Research ◽

Immune Priming ◽

Social Bees ◽

Bee Health ◽

Landscape Scales ◽

And Function ◽

Solitary Species

Parasites are linked to the decline of some bee populations; thus, understanding defense mechanisms has important implications for bee health. Recent advances have improved our understanding of factors mediating bee health ranging from molecular to landscape scales, but often as disparate literatures. Here, we bring together these fields and summarize our current understanding of bee defense mechanisms including immunity, immunization, and transgenerational immune priming in social and solitary species. Additionally, the characterization of microbial diversity and function in some bee taxa has shed light on the importance of microbes for bee health, but we lack information that links microbial communities to parasite infection in most bee species. Studies are beginning to identify how bee defense mechanisms are affected by stressors such as poor-quality diets and pesticides, but further research on this topic is needed. We discuss how integrating research on host traits, microbial partners, and nutrition, as well as improving our knowledge base on wild and semi-social bees, will help inform future research, conservation efforts, and management.

Download Full-text