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Sample records for arachidonic acid-induced ear

  1. Arachidonic acid induces brain endothelial cell apoptosis via p38-MAPK and intracellular calcium signaling.

    PubMed

    Evans, Justin; Ko, YooSeung; Mata, Wilmer; Saquib, Muhammad; Eldridge, Joel; Cohen-Gadol, Aaron; Leaver, H Anne; Wang, Shukun; Rizzo, Maria Teresa

    2015-03-01

    Arachidonic acid (AA), a bioactive fatty acid whose levels increase during neuroinflammation, contributes to cerebral vascular damage and dysfunction. However, the mode of injury and underlying signaling mechanisms remain unknown. Challenge of primary human brain endothelial cells (HBECs) with AA activated a stress response resulting in caspase-3 activation, poly(ADP-ribose) polymerase cleavage, and disruption of monolayer integrity. AA also induced loss of mitochondrial membrane potential and cytochrome c release consistent with activation of intrinsic apoptosis. HBEC stimulation with AA resulted in sustained p38-MAPK activation and subsequent phosphorylation of mitogen-activated protein kinase activated protein-2 (MAPKAP-2) kinase and heat shock protein-27 (Hsp27). Conversely, other unsaturated and saturated fatty acids had no effect. Pharmacological and RNA interference-mediated p38? or p38? suppression abrogated AA signaling to caspase-3 and Hsp27, suggesting involvement of both p38 isoforms in AA-induced HBEC apoptosis. Hsp27 silencing also blocked caspase-3 activation. AA stimulated intracellular calcium release, which was attenuated by inositol 1,4,5-trisphosphate (IP3) receptor antagonists. Blockade of intracellular calcium release decreased caspase-3 activation, but had no effect on AA-induced p38-MAPK activation. However, inhibition of p38-MAPK or blockade of intracellular calcium mobilization abrogated AA-induced cytochrome c release. AA-induced caspase-3 activation was abrogated by pharmacological inhibition of lipooxygenases. These findings support a previously unrecognized signaling cooperation between p38-MAPK/MAPKAP-2/Hsp27 and intracellular calcium release in AA-induced HBEC apoptosis and suggest its relevance to neurological disorders associated with vascular inflammation. PMID:24802256

  2. The Polyunsaturated Fatty Acids Arachidonic Acid and Docosahexaenoic Acid Induce Mouse Dendritic Cells Maturation but Reduce T-Cell Responses In Vitro

    PubMed Central

    Carlsson, Johan A.; Wold, Agnes E.; Sandberg, Ann-Sofie; stman, Sofia M.

    2015-01-01

    Long-chain polyunsaturated fatty acids (PUFAs) might regulate T-cell activation and lineage commitment. Here, we measured the effects of omega-3 (n-3), n-6 and n-9 fatty acids on the interaction between dendritic cells (DCs) and nave T cells. Spleen DCs from BALB/c mice were cultured in vitro with ovalbumin (OVA) with 50 ?M fatty acids; ?-linolenic acid, arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), linoleic acid or oleic acid and thereafter OVA-specific DO11.10 T cells were added to the cultures. Fatty acids were taken up by the DCs, as shown by gas chromatography analysis. After culture with arachidonic acid or DHA CD11c+ CD11b+ and CD11c+ CD11bneg DCs expressed more CD40, CD80, CD83, CD86 and PDL-1, while IAd remained unchanged. However, fewer T cells co-cultured with these DCs proliferated (CellTrace Violetlow) and expressed CD69 or CD25, while more were necrotic (7AAD+). We noted an increased proportion of T cells with a regulatory T cell (Treg) phenotype, i.e., when gating on CD4+ FoxP3+ CTLA-4+, CD4+ FoxP3+ Helios+ or CD4+ FoxP3+ PD-1+, in co-cultures with arachidonic acid- or DHA-primed DCs relative to control cultures. The proportion of putative Tregs was inversely correlated to T-cell proliferation, indicating a suppressive function of these cells. With arachidonic acid DCs produced higher levels of prostaglandin E2 while T cells produced lower amounts of IL-10 and IFN?. In conclusion arachidonic acid and DHA induced up-regulation of activation markers on DCs. However arachidonic acid- and DHA-primed DCs reduced T-cell proliferation and increased the proportion of T cells expressing FoxP3, indicating that these fatty acids can promote induction of regulatory T cells. PMID:26619195

  3. Anti-Inflammatory and Analgesic Effects of Pyeongwisan on LPS-Stimulated Murine Macrophages and Mouse Models of Acetic Acid-Induced Writhing Response and Xylene-Induced Ear Edema

    PubMed Central

    Oh, You-Chang; Jeong, Yun Hee; Cho, Won-Kyung; Ha, Jeong-Ho; Gu, Min Jung; Ma, Jin Yeul

    2015-01-01

    Pyeongwisan (PW) is an herbal medication used in traditional East Asian medicine to treat anorexia, abdominal distension, borborygmus and diarrhea caused by gastric catarrh, atony and dilatation. However, its effects on inflammation-related diseases are unknown. In this study, we investigated the biological effects of PW on lipopolysaccharide (LPS)-mediated inflammation in macrophages and on local inflammation in vivo. We investigated the biological effects of PW on the production of inflammatory mediators, pro-inflammatory cytokines and related products as well as the activation of nuclear factor kappa B (NF-?B) and mitogen-activated protein kinases (MAPKs) in LPS-stimulated macrophages. Additionally, we evaluated the analgesic effect on the acetic acid-induced writhing response and the inhibitory activity on xylene-induced ear edema in mice. PW showed anti-inflammatory effects by inhibiting the production of nitric oxide (NO), tumor necrosis factor-? (TNF-?) and interleukin-6 (IL-6) and interleukin-1? (IL-1?). In addition, PW strongly suppressed inducible nitric oxide synthase (iNOS), a NO synthesis enzyme, induced heme oxygenase-1 (HO-1) expression and inhibited NF-?B activation and MAPK phosphorylation. Also, PW suppressed TNF-?, IL-6 and IL-1? cytokine production in LPS-stimulated peritoneal macrophage cells. Furthermore, PW showed an analgesic effect on the writhing response and an inhibitory effect on mice ear edema. We demonstrated the anti-inflammatory effects and inhibitory mechanism in macrophages as well as inhibitory activity of PW in vivo for the first time. Our results suggest the potential value of PW as an inflammatory therapeutic agent developed from a natural substance. PMID:25569097

  4. Calcium mobilization by arachidonic acid in trypanosomatids.

    PubMed

    Catisti, R; Uyemura, S A; Docampo, R; Vercesi, A E

    2000-02-01

    A recent report (Eintracht J, Maathai R, Mellors A, Ruben L. Calcium entry in Trypanosoma brucei is regulated by phospholipase A, and arachidonic acid, Biochem J 1998:336:659-66) provided evidence that calcium entry in Trypanosoma brucei bloodstream trypomastigotes is regulated via a signaling pathway involving phospholipase A2-mediated generation of arachidonic acid and stimulation of a plasma membrane-located calcium channel. Here we show that Ca2+ influx in T. brucei procyclic trypomastigotes, Leishmania donovani promastigotes and T. cruzi amastigotes was also stimulated in a dose-dependent manner (50-400 nM) by the amphiphilic peptide melittin. This effect was blocked by the phospholipase A, inhibitor 3-(4-octadecyl)-benzoylacrylic acid. The unsaturated fatty acid arachidonic acid, in the range of 10-75 microM, induced Ca2+ entry by a mechanism sensitive to LaCl3. However, both melittin and arachidonic acid induced an increase in [Ca2+]i in T. brucei procyclic trypomastigotes incubated in Ca2+-free medium implying Ca2+ mobilization from intracellular stores. This hypothesis was supported by experiments showing that arachidonic acid promoted Ca2+ release from the acidocalcisomes of these cells. The results showing changes in mitochondrial membrane potential, release of acridine orange and Ca2+ from the acidocalcisomes and Ca2+ transport across the plasma membrane suggest that in addition to the possible stimulation of a Ca2+ channel-mediated process, arachidonic acid, in the range of concentrations used here, have other nonspecific effects on the trypanosomatids membranes. PMID:10693748

  5. Pierced Ears

    MedlinePLUS

    ... Skiing, Snowboarding, Skating Crushes What's a Booger? Pierced Ears KidsHealth > For Kids > Pierced Ears Print A A ... cool, but infected ears do not! Getting Your Ears Pierced It's important to get your ears pierced ...

  6. Ear Infections

    MedlinePLUS

    MENU Return to Web version Ear Infections Overview How does the ear work? The ear works by receiving sound waves and sending messages to the brain. The outer ear includes the part of the ear you can ...

  7. Arachidonic acid is a physiological activator of the ryanodine receptor in pancreatic beta-cells.

    PubMed

    Woolcott, Orison O; Gustafsson, Amanda J; Dzabic, Mensur; Pierro, Cristina; Tedeschi, Patrizia; Sandgren, Johanna; Bari, M Rizuanul; Nguyen, K Hoa; Bianchi, Marta; Rakonjac, Marija; Rdmark, Olof; Ostenson, Claes-Gran; Islam, Md Shahidul

    2006-06-01

    Pancreatic beta-cells have ryanodine receptors but little is known about their physiological regulation. Previous studies have shown that arachidonic acid releases Ca(2+) from intracellular stores in beta-cells but the identity of the channels involved in the Ca(2+) release has not been elucidated. We studied the mechanism by which arachidonic acid induces Ca(2+) concentration changes in pancreatic beta-cells. Cytosolic free Ca(2+) concentration was measured in fura-2-loaded INS-1E cells and in primary beta-cells from Wistar rats. The increase of cytosolic Ca(2+) concentration induced by arachidonic acid (150microM) was due to both Ca(2+) release from intracellular stores and influx of Ca(2+) from extracellular medium. 5,8,11,14-Eicosatetraynoic acid, a non-metabolizable analogue of arachidonic acid, mimicked the effect of arachidonic acid, indicating that arachidonic acid itself mediated Ca(2+) increase. The Ca(2+) release induced by arachidonic acid was from the endoplasmic reticulum since it was blocked by thapsigargin. 2-Aminoethyl diphenylborinate (50microM), which is known to inhibit 1,4,5-inositol-triphosphate-receptors, did not block Ca(2+) release by arachidonic acid. However, ryanodine (100microM), a blocker of ryanodine receptors, abolished the effect of arachidonic acid on Ca(2+) release in both types of cells. These observations indicate that arachidonic acid is a physiological activator of ryanodine receptors in beta-cells. PMID:16620964

  8. Ear Tubes

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    ... Meeting Calendar Find an ENT Doctor Near You Ear Tubes Ear Tubes Patient Health Information News media ... and throat specialist) may be considered. What are ear tubes? Ear tubes are tiny cylinders placed through ...

  9. Ear emergencies

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    Ear emergencies include objects in the ear canal and ruptured eardrums. ... Children often put objects into their ears. These objects can be hard to remove. The ear canal is a tube of solid bone that is lined with thin, sensitive ...

  10. Swimmer's Ear

    MedlinePLUS

    ... Skiing, Snowboarding, Skating Crushes What's a Booger? Swimmer's Ear KidsHealth > For Kids > Swimmer's Ear Print A A ... How Do I Know if I Have Swimmer's Ear? Swimmer's ear may start with some itching, but ...

  11. Pierced Ears

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    ... System How the Body Works Main Page Pierced Ears KidsHealth > Kids > Puberty & Growing Up > Girl Stuff > Pierced ... cool, but infected ears do not! Getting Your Ears Pierced It's important to get your ears pierced ...

  12. Ear examination

    MedlinePLUS

    An ear exam is performed when a health care provider looks inside your ear using an instrument called an otoscope. ... the head tilted toward the shoulder opposite the ear being examined. The provider will gently pull up, ...

  13. Cauliflower Ear

    MedlinePLUS

    ... Snowboarding, Skating Crushes What's a Booger? What's Cauliflower Ear? KidsHealth > For Kids > What's Cauliflower Ear? Print A A A Text Size Have you ever seen someone whose ear looks bumpy and lumpy? The person might have ...

  14. Ear Infections

    MedlinePLUS

    ... middle ear and is called otitis media. The tubes inside the ears become clogged with fluid and ... infections often may need surgery to place small tubes inside their ears. The tubes relieve pressure in ...

  15. Ear Disorders

    MedlinePLUS

    ... ear, where they make your eardrum vibrate. The vibrations are transmitted through three tiny bones, called ossicles, in your middle ear. The vibrations travel to your inner ear, a snail-shaped ...

  16. Ear Pieces

    ERIC Educational Resources Information Center

    DiJulio, Betsy

    2011-01-01

    In this article, the author describes an art project wherein students make fanciful connections between art and medicine. This project challenges students to interpret "ear idioms" (e.g. "blow it out your ear," "in one ear and out the other") by relying almost entirely on realistic ear drawings, the placement of them, marks, and values. In that…

  17. Ear Pieces

    ERIC Educational Resources Information Center

    DiJulio, Betsy

    2011-01-01

    In this article, the author describes an art project wherein students make fanciful connections between art and medicine. This project challenges students to interpret "ear idioms" (e.g. "blow it out your ear," "in one ear and out the other") by relying almost entirely on realistic ear drawings, the placement of them, marks, and values. In that

  18. Your Ears

    MedlinePLUS

    ... Protect your hearing by wearing earplugs at loud music concerts and around noisy machinery, like in wood ... For Parents MORE ON THIS TOPIC Can Loud Music Hurt My Ears? What Is an Ear Infection? ...

  19. Ear Injury

    MedlinePLUS

    ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ... Drugs Ear, Nose, and Throat Disorders Eye Disorders Fundamentals Heart and Blood Vessel Disorders Hormonal and Metabolic ...

  20. Ear Injury

    MedlinePLUS

    ... Video) Rotator Cuff Injury Additional Content Medical News Ear Injury By Sam P. Most, MD NOTE: This ... Professional Version Facial Injuries Introduction to Facial Injuries Ear Injury Fractures of the Nose Fractures of the ...

  1. Elephant ear

    MedlinePLUS

    Elephant ear plants are indoor or outdoor plants with very large, arrow-shaped leaves. Poisoning may occur if you ... Elephant ear grows naturally in tropical and subtropical areas, but is easily found in northern climates as well.

  2. Ear barotrauma

    MedlinePLUS

    Barotitis media; Barotrauma; Ear popping; Pressure-related ear pain; Eustachian tube dysfunction ... The air pressure in the middle ear is most often the same as the air pressure outside of the body. The Eustachian tube is a connection between the middle ...

  3. Ear Infections in Children

    MedlinePLUS

    ... Home » Health Info » Hearing, Ear Infections, and Deafness Ear Infections in Children On this page: What is ... additional information about ear infections? What is an ear infection? An ear infection is an inflammation of ...

  4. Swimmer's ear

    MedlinePLUS

    ... or a respiratory infection such as a cold. Swimming in unclean water can lead to swimmer's ear. ... very well after it has gotten wet. Avoid swimming in polluted water. Use earplugs when swimming. Try ...

  5. Effects of NSAIDs on the Inner Ear: Possible Involvement in Cochlear Protection

    PubMed Central

    Hoshino, Tomofumi; Tabuchi, Keiji; Hara, Akira

    2010-01-01

    Cyclooxygenase and lipoxygenase, two important enzymes involved in arachidonic acid metabolism, are major targets of non-steroidal anti-inflammatory drugs (NSAIDs). Recent investigations suggest that arachidonic cascades and their metabolites may be involved in maintaining inner ear functions. The excessive use of aspirin may cause tinnitus in humans and impairment of the outer hair cell functions in experimental animals. On the other hand, NSAIDs reportedly exhibit protective effects against various kinds of inner ear disorder. The present review summarizes the effects of NSAIDs on cochlear pathophysiology. NSAIDs are a useful ameliorative adjunct in the management of inner ear disorders.

  6. Ear wax

    MedlinePLUS

    ... is one of the most common causes of hearing loss. ... is plugged Noises in the ear (tinnitus) Partial hearing loss, may get worse ... become blocked with wax again in the future. Hearing loss is often temporary. In most cases, hearing returns ...

  7. Ear Plastic Surgery

    MedlinePLUS

    ... Meeting Calendar Find an ENT Doctor Near You Ear Plastic Surgery Ear Plastic Surgery Patient Health Information ... they may improve appearance and self-confidence. Can Ear Deformities Be Corrected? Formation of the ear during ...

  8. Better Ear Health

    MedlinePLUS

    ... Calendar Find an ENT Doctor Near You Better Ear Health Better Ear Health Patient Health Information News ... often helpful to those with this condition. Swimmer’s Ear An infection of the outer ear structures caused ...

  9. How the Ear Works

    MedlinePLUS

    ... Find an ENT Doctor Near You How the Ear Works How the Ear Works Patient Health Information News media interested in ... public relations staff at newsroom@entnet.org . The ear has three main parts: the outer ear (including ...

  10. Ear Infection and Vaccines

    MedlinePLUS

    ... Meeting Calendar Find an ENT Doctor Near You Ear Infection and Vaccines Ear Infection and Vaccines Patient Health Information News media ... who suffer from the most common type of ear infection, called middle ear infection or otitis media ( ...

  11. Autoimmune Inner Ear Disease

    MedlinePLUS

    ... Find an ENT Doctor Near You Autoimmune Inner Ear Disease Autoimmune Inner Ear Disease Patient Health Information ... with a hearing loss. How Does the Healthy Ear Work? The ear has three main parts: the ...

  12. Caring for Pierced Ears

    MedlinePLUS

    ... care Caring for pierced ears Caring for pierced ears Although ear piercings are more common and can be less ... handled safely. For anyone thinking about getting their ears pierced, dermatologists urge people to follow these steps ...

  13. Swimmer's Ear (For Parents)

    MedlinePLUS

    ... Emergency Cerebral Palsy: Caring for Your Child Swimmer's Ear (Otitis Externa) KidsHealth > For Parents > Swimmer's Ear (Otitis ... espaol Otitis del nadador (otitis externa) About Swimmer's Ear Otitis externa commonly known as swimmer's ear is ...

  14. Role of arachidonic acid cascade in Rhinella arenarum oocyte maturation.

    PubMed

    Ortiz, Maria Eugenia; Arias-Torres, Ana Josefina; Zelarayn, Liliana Isabel

    2015-08-01

    There are no studies that document the production of prostaglandins (PGs) or their role in Rhinella arenarum oocyte maturation. In this study, we analysed the effect of arachidonic acid (AA) and prostaglandins (PGs) on maturation, activation and pronuclear formation in R. arenarum oocytes. Our results demonstrated that AA was capable of inducing maturation in time-dependent and dose-dependent manner. Arachidonic acid-induced maturation was inhibited by indomethacin. PGs from AA hydrolysis, such as prostaglandin F2? (PGF2?) and, to a lesser extent, PGE2, induced meiosis resumption. Oocyte maturation in response to PGF2? was similar to that produced by progesterone (P4). Oocyte response to PGE1 was scarce. Rhinella arenarum oocyte PGF2?-induced maturation showed seasonal variation. From February to June, oocytes presented low sensitivity to PGF2?. In following periods, this response increased until a maximum was reached during October to January, a close temporal correlation with oocyte response to P4 being observed. The effect of PGF2? on maturation was verified by analysing the capacity of oocytes to activate and form pronuclei after being injected with homologous sperm. The cytological analysis of activated oocytes demonstrated the absence of cortical granules in oocytes, suggesting that PGF2? induces germinal vesicle breakdown (GVBD) and meiosis resumption up to metaphase II. In turn, oocytes matured by the action of PGF2? were able to form pronuclei after fertilization in a similar way to oocyte maturated by P4. In microinjection of mature cytoplasm experiments, the transformation of pre-maturation promoting factor (pre-MPF) to MPF was observed when oocytes were treated with PGF2?. In summary, our results illustrated the participation of the AA cascade and its metabolites in maturation, activation and pronuclei formation in R. arenarum. PMID:24964276

  15. Caring for Pierced Ears

    MedlinePLUS

    ... Video library Find a dermatologist Caring for pierced ears Although ear piercings are more common and can be less ... handled safely. For anyone thinking about getting their ears pierced, dermatologists urge people to follow these steps ...

  16. Ears and Altitude

    MedlinePLUS

    ... Meeting Calendar Find an ENT Doctor Near You Ears and Altitude Ears and Altitude Patient Health Information ... uncomfortable feeling of fullness or pressure. Why do ears pop? Normally, swallowing causes a little click or ...

  17. Ear infection - chronic

    MedlinePLUS

    Middle ear infection - chronic; Otitis media - chronic; Chronic otitis media; Chronic ear infection ... blocked, fluid can build up. When this happens, infection can occur. A chronic ear infection develops when ...

  18. "Swimmer's Ear" (Otitis Externa) Prevention

    MedlinePLUS

    ... Healthy Swimming Healthy Water Home Share Compartir "Swimmer’s Ear" (Otitis Externa) Prevention Swimmer's ear (also known as ... Health with CDC: Keep Your Ears Dry Swimmer’s Ear Prevention Tips DO keep your ears as dry ...

  19. Swimmer's Ear (External Otitis)

    MedlinePLUS

    ... Can I Help a Friend Who Cuts? Swimmer's Ear (External Otitis) KidsHealth > For Teens > Swimmer's Ear (External Otitis) Print A A A Text Size ... Ryan woke with a sharp pain in his ear — it really hurt! He remembered having ear infections ...

  20. Swimmer's Ear (External Otitis)

    MedlinePLUS

    ... Can I Help a Friend Who Cuts? Swimmer's Ear (External Otitis) KidsHealth > For Teens > Swimmer's Ear (External Otitis) Print A A A Text Size ... Ryan woke with a sharp pain in his ear it really hurt! He remembered having ear infections ...

  1. Ear drainage culture

    MedlinePLUS

    ... needed. Your health care provider will use a cotton swab to collect the sample from inside the ... Using a cotton swab to take a sample of drainage from the outer ear is not painful. However, ear pain may ...

  2. Middle ear infection (image)

    MedlinePLUS

    A middle ear infection is also known as otitis media. It is one of the most common of childhood infections. With this illness, the middle ear becomes red, swollen, and inflamed because of bacteria ...

  3. Middle Ear Infections

    MedlinePLUS

    ... Listen Español Text Size Email Print Share Middle Ear Infections Page Content Article Body What are the ... illness. What if a child with a middle ear infection is in great pain and discomfort? The ...

  4. Travel Inside the Ear

    MedlinePLUS Videos and Cool Tools

    ... Deafness Travel Inside the Ear Video When sound waves reach your ear, you know you've heard ... the sound through the hair cells to your brain. Last Updated Date: July 30, 2014 Languages Español ...

  5. Stimulation of arachidonic acid release from thyroid phospholipids.

    PubMed

    Stelmach, H; Jaroszewicz, L

    1995-12-01

    The present study demonstrates that exposure of pig thyroid slices to thyrotropin stimulates the arachidonate release from endogenous phospholipids. The experiments with 14C-arachidonic acid show that the release of arachidonic acid is mostly from phosphatidylcholine, phosphatidylinositol and neutral lipids. The liberation of arachidonate from thyroid phospholipids is Ca2+ dependent. The addition of calcium ionophore A23187 to medium augments the release of arachidonate. Addition of ionophore and egzogenous Ca2+ markedly stimulates the arachidonate release, what suggests that thyroid phospholipase A2 can be regulated by the extend of saturation of the enzyme with Ca2+. The arachidonate release from phospholipids caused by thyrotropin is potentiated by adenosine. This effect shows that adenosine modulates TSH action and supports the idea that adenosine takes part in the physiological regulation of thyroid cells. PMID:8770788

  6. Middle Ear Infections (For Parents)

    MedlinePLUS

    ... for Your Child All About Food Allergies Middle Ear Infections KidsHealth > For Parents > Middle Ear Infections Print ... 3 years old. A Close Look at the Ear To understand how ear infections develop, let's review ...

  7. Fusion of the ear bones

    MedlinePLUS

    Fusion of the ear bones is the joining of the bones of the inner ear. These are the incus, malleus, and stapes bones. Related topics include: Chronic ear infection Otosclerosis Middle ear malformations

  8. Flying and Your Child's Ears

    MedlinePLUS

    ... All About Food Allergies Flying and Your Child's Ears KidsHealth > For Parents > Flying and Your Child's Ears ... a) cuando vuele en avión Flying's Effects on Ears Many of us have felt that weird ear- ...

  9. What Is an Ear Infection?

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    ... System How the Body Works Main Page What Is an Ear Infection? KidsHealth > Kids > Illnesses & Injuries > I ... can cause ear pain and a fever . What Is a Middle Ear Infection? Middle ear infections are ...

  10. What Is an Ear Infection?

    MedlinePLUS

    ... Skiing, Snowboarding, Skating Crushes What's a Booger? What Is an Ear Infection? KidsHealth > For Kids > What Is ... can cause ear pain and a fever . What Is a Middle Ear Infection? Middle ear infections are ...

  11. Flying and Your Child's Ears

    MedlinePLUS

    ... Caring for Your Child Flying and Your Child's Ears KidsHealth > For Parents > Flying and Your Child's Ears ... a) cuando vuele en avin Flying's Effects on Ears Many of us have felt that weird ear- ...

  12. Middle Ear Infections (For Parents)

    MedlinePLUS

    ... Emergency Cerebral Palsy: Caring for Your Child Middle Ear Infections KidsHealth > For Parents > Middle Ear Infections Print ... 3 years old. A Close Look at the Ear To understand how ear infections develop, let's review ...

  13. Ear, Nose & Throat Issues & Down Syndrome

    MedlinePLUS

    ... Associated Conditions » Ear, Nose & Throat Issues & Down Syndrome Ear, Nose & Throat Issues & Down Syndrome Ear, nose, and ... Are Common in Children With Down Syndrome? External Ear Canal Stenosis Stenotic ear canals (narrow ear canals) ...

  14. Pathology of the Ear

    PubMed Central

    Orengo, Ida; Robbins, Kerri; Marsch, Amanda

    2011-01-01

    The external ear is exposed to weathering and trauma; it also has sparse vascularity, making it prone to infection and disease. The external location of the cutaneous ear makes it easily visible for diagnosis and accessible for treatment. In this article, the authors focus on diseases of the ear that are most commonly encountered and may be subject to surgical and medical evaluation and/or treatment. Epidemiology, pathogenesis, clinical course, and treatment for each disease entity are discussed. PMID:23115534

  15. Ear - blocked at high altitudes

    MedlinePLUS

    ... ears; Flying and blocked ears; Eustachian tube dysfunction - high altitude ... the middle ear and the back of the nose and upper throat. ... down from high altitudes. Chewing gum the entire time you are ...

  16. How to Use Ear Drops

    MedlinePLUS

    How to Use Ear Drops(Having someone else give you the ear drops may make this procedure easier.) Wash your hands thoroughly with soap and warm water. Gently clean your ear with a damp facecloth and then dry your ...

  17. Avoiding Infection After Ear Piercing

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    ... Text Size Email Print Share Avoiding Infection After Ear Piercing Page Content Article Body What is the best way to avoid infection after ear piercing? Ears may be pierced for cosmetic reasons ...

  18. Taking Care of Your Ears

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    ... Body Works Main Page Taking Care of Your Ears KidsHealth > Kids > Staying Healthy > Being Good to My ... you clean it out. Taking Care of Pierced Ears Pierced ears may look pretty, but you need ...

  19. Ear tube insertion - series (image)

    MedlinePLUS

    Ear tube insertion is recommended for: fluid in the middle ear (present for more than 12 weeks) recurrent ear ... the accumulated fluid is suctioned out. A small tube is inserted through the incised eardrum in order ...

  20. New uses of bioglycerin: production of arachidonic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Filamentous fungi of the genus Mortierella are known to produce arachidonic acid from glucose and M. alpina is currently used in industrial scale production of arachidonic acid in Japan. In anticipation of a large excess of co-product bioglycerin from the national biodiesel program, we would like ...

  1. Mefenamic Acid Induced Nephrotoxicity: An Animal Model

    PubMed Central

    Somchit, Muhammad Nazrul; Sanat, Faizah; Hui, Gan Eng; Wahab, Shahrin Iskandar; Ahmad, Zuraini

    2014-01-01

    Purpose: Nonsteroidal anti-inflammatory drugs (NSAIDs) are used for the treatment of many joint disorders, inflammation and to control pain. Numerous reports have indicated that NSAIDs are capable of producing nephrotoxicity in human. Therefore, the objective of this study was to evaluate mefenamic acid, a NSAID nephrotoxicity in an animal model. Methods: Mice were dosed intraperitoneally with mefenamic acid either as a single dose (100 or 200 mg/kg in 10% Dimethyl sulfoxide/Palm oil) or as single daily doses for 14 days (50 or 100 mg/kg in 10% Dimethyl sulfoxide/Palm oil per day). Venous blood samples from mice during the dosing period were taken prior to and 14 days post-dosing from cardiac puncture into heparinized vials. Plasma blood urea nitrogen (BUN) and creatinine activities were measured. Results: Single dose of mefenamic acid induced mild alteration of kidney histology mainly mild glomerular necrosis and tubular atrophy. Interestingly, chronic doses induced a dose dependent glomerular necrosis, massive degeneration, inflammation and tubular atrophy. Plasma blood urea nitrogen was statistically elevated in mice treated with mefenamic acid for 14 days similar to plasma creatinine. Conclusion: Results from this study suggest that mefenamic acid as with other NSAIDs capable of producing nephrotoxicity. Therefore, the study of the exact mechanism of mefenamic acid induced severe nephrotoxicity can be done in this animal model. PMID:25436198

  2. [Peroxidation of arachidonic acid and brain edema].

    PubMed

    Aritake, K; Wakai, S; Asano, T; Takakura, K

    1983-10-01

    Recent studies suggest that peroxidation of arachidonic acid (AA) accumulating during ischemic insult, may be related to the occurrence of post-ischemic brain damage. Since the influence of the increased brain content of AA remains unclear, the present study was undertaken to explore whether the intracerebral injection of AA is associated with the injury of the surrounding brain tissues such as brain edema. Rats received the intracerebral injection of 10 microliters of test solution (160 microgram of AA emulsified in 1% bovine serum albumin, BSA) or the same volume of BSA as the control. The measurement of specific gravity (SG) (74 rats) and the local CBF by H2 clearance technique (21 rats), and electron microscopical studies with tracers (Evans blue and horseradish peroxidase, HRP) (24 rats) were carried out. The effect of pretreatment with indomethacin (PI, 10 mg/kg) was evaluated in separate groups. AA transiently produced a significant decrease in SG and in 1CBF adjacent to the injection sites (p less than 0.01). The increased pinocytotic transportation, an accumulation of edema fluid containing HRP in extracellular space and endothelial injuries were observed only after AA injection. The above-mentioned falls in SG and in 1CBF, and the extravasation of HRP were inhibited by PI. The fact that PI prevented the edema formation, 1CBF change and the disturbance of blood-brain barrier induced by AA, indicates that peoxidation of AA through the arachidonate cascade is involved in the mechanism of brain edema formation.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6651981

  3. Ear infection - acute

    MedlinePLUS

    ... Risk factors for acute ear infections include: Attending day care (especially centers with more than 6 children) Changes ... hands and toys often. If possible, choose a day care that has 6 or fewer children. This can ...

  4. Ear Injuries (For Parents)

    MedlinePLUS

    ... head, sports injuries, and even listening to loud music can cause ear damage, which can affect hearing ... But for kids and teens, listening to loud music (at concerts, in the car, through headphones) is ...

  5. Ear Infections in Children

    MedlinePLUS

    ... have identified colonies of antibiotic-resistant bacteria, called biofilms, that are present in the middle ears of ... infections. Understanding how to attack and kill these biofilms would be one way to successfully treat chronic ...

  6. ANALYSIS OF ARACHIDONIC ACID METABOLITE AND PLATELET ACTIVATING FACTOR PRODUCTION

    EPA Science Inventory

    Metabolites of arachidonic acid ("eicosanoids") and platelet activating factor are important bioactive lipids that may be involved in the pathobiological alterations in animals induced by pollutant exposure. nalysis of these substances in biological tissue and fluids is important...

  7. Human polymorphonuclear neutrophil activation with arachidonic acid.

    PubMed Central

    Smith, R. J.; Sam, L. M.; Justen, J. M.; Leach, K. L.; Epps, D. E.

    1987-01-01

    The capacity of arachidonic acid (AA) to stimulate granule exocytosis from human polymorphonuclear neutrophils (PMNs) was investigated. AA induced the selected extracellular release of azurophil (myeloperoxidase, lysozyme) and specific (lysozyme, vitamin B12 binding protein) granule constituents from human PMNs in a time- and concentration-dependent manner. Cytochalasin B (CB) enhanced but was not required for PMN activation with AA. Although extracellular calcium had no effect on granule exocytosis, AA did stimulate the mobilization of intracellular sequestered Ca2+ which resulted in an increase in cytosolic-free Ca2+ ([Ca2+]i) as reflected by increased fluorescence of Fura-2-treated cells. AA stimulated Ca2+/phospholipid-dependent protein kinase C (PK-C) activity in PMNs. 4,4'-Diisothiocyano-2,2'-disulphonic acid stilbene (DIDS), an anion channel blocker, caused a concentration-dependent inhibition of granule enzyme release. Activation of PMNs with AA was unaffected by the lipoxygenase/cycle-oxygenase inhibitors, 5,8,11, 14-eicosatetraynoic acid (ETYA) and benoxaprofen, a lipoxygenase inhibitor, 6, 9, deepoxy-6,9-(phenylimino) delta 6,8-prostaglandin 1(1) (piriprost potassium) or a pure cyclo-oxygenase inhibitor, flurbiprofen. These data define the properties of AA as a secretory stimulus for human PMNs. PMID:3111576

  8. Biochemical and subcellular distribution of arachidonic acid in rat myocardium

    SciTech Connect

    Miyazaki, Y.; Gross, R.W.; Sobel, B.E.; Saffitz, J.E. )

    1987-12-01

    Selective release of arachidonic acid from prelabeled phospholipid pools has been observed following exposure of neonatal rat cardiac myocytes to metabolic inhibitors in vitro and has been correlated temporally with the development of irreversible sarcolemmal damage. Hydrolysis of phospholipids with release of arachidonic acid may be an important mechanism in the pathogenesis of sarcolemmal damage induced by ischemia. To elucidate potential subcellular loci of arachidonic acid release in ischemic myocardium, the authors characterized the phospholipid composition of adult rat myocardial sarcolemma and delineated the biochemical and subcellular distribution of radiolabeled arachidonic acid in neonatal rat myocytes incubated with ({sup 3}H)-arachidonic acid for selected intervals. Radioactivity was located almost exclusively in mitochondria and internal cytoplasmic membranes (primarily sarcoplasmic reticulum), which collectively contained 90% of myocyte radioactivity. These results indicate that radiolabeled arachidonic acid released from prelabeled phospholipid pools on exposure of neonatal rat myocytes to oxidative inhibitors is derived from mitochondria and internal cell membranes. The diminutive labeling of the sarcolemma suggests that turnover of arachidonoyl phospholipids is slower in the sarcolemma than in other membranous organelles.

  9. Ear replantation without microsurgery.

    PubMed

    Pribaz, J J; Crespo, L D; Orgill, D P; Pousti, T J; Bartlett, R A

    1997-06-01

    Reconstitution of the amputated ear remains a challenge to the plastic surgeon. Reattachment as a composite graft of the total or subtotal amputated ear is unreliable. Microsurgical replantation can be performed in a minority of cases; however, difficulty with adequate venous drainage complicates the technical complexity of these cases. To enhance survival of a reattached ear segment, Mladick et al. advocated use of the retroauricular pocket principle. This technique involves deepithelialization of the amputated part, followed by anatomic reattachment to the amputation stump and then burial in a retroauricular pocket. This simple technique increases the surface area of the avulsed segment in contact with surrounding nutrients, maximizing the probability of "take." The relationship between the dermis and cartilage is preserved, thus minimizing the deformity from cartilage warping. The undisturbed dermis on the involved segment can reepithelialize spontaneously, negating the need for a skin graft. We have used this technique successfully in five of six patients. PMID:9180709

  10. Amoxicillin/Clavulanic Acid-Induced Thrombocytopenia

    PubMed Central

    Saad, Aline; Azar, Marina; Khoueiry, Paul

    2014-01-01

    Introduction and Objective: Drug-induced thrombocytopenia is a common adverse effect reported in the literature. Typically patients present with a low platelet count with signs and symptoms ranging from bruising to bleeding, and major organ damage. Penicillin-induced thrombocytopenia previously reported in the literature is explained primarily through the hapten-dependent antibody process. The goal of this report is to present a case of an amoxicillin/clavulanic acid-induced thrombocytopenia. Case Presentation: A 23-year-old male presented to the emergency department with bruises on his arms and legs after completing a full course of amoxicillin/clavulanic acid of 625 mg twice a day for 5 days for tonsillitis. After several tests, the patient was diagnosed with thrombocytopenia induced by amoxicillin/clavulanic acid. The patient was treated with a corticosteroids taper regimen for 3 weeks. He was discharged after 3 days of inpatient treatment with instructions to avoid physical activity for 2 weeks. Two weeks post discharge, the follow-up showed that the platelet count had increased. Discussion: Penicillin-induced thrombocytopenia has been previously reported in the inpatient setting where bleeding was observed. However, the patient in this case report presented with bruises on his arms and legs. The diagnosis was made by the process of elimination; not all possible tests were conducted. The patient was prescribed corticosteroids that are not indicated for drug-induced thrombocytopenia. The Naranjo scale showed that this is a probable adverse event of amoxicillin/clavulanic acid. Conclusion: This is a unique case where amoxicillin/clavulanic acid was reported to be a probable cause of thrombocytopenia in an outpatient setting without signs of bleeding and without concomitant medications. PMID:25477568

  11. Hearing, Ear Infections, and Deafness

    MedlinePLUS

    ... Involved You are here Home » Health Info Hearing, Ear Infections, and Deafness Diseases and Conditions Age-Related Hearing Loss Auditory Neuropathy Auditory Processing Disorder Ear Infections in Children Enlarged Vestibular Aqueducts and Childhood ...

  12. From Ear to Brain

    ERIC Educational Resources Information Center

    Kimura, Doreen

    2011-01-01

    In this paper Doreen Kimura gives a personal history of the "right-ear effect" in dichotic listening. The focus is on the early ground-breaking papers, describing how she did the first dichotic listening studies relating the effects to brain asymmetry. The paper also gives a description of the visual half-field technique for lateralized stimulus…

  13. Travel Inside the Ear

    MedlinePLUS Videos and Cool Tools

    ... form Search A–Z Index Español Menu Home Health Info Hearing, Ear Infections, and Deafness Balance Taste ... Voice, Speech, and Language Información en español Statistics Health Resources Clinical Studies Research Extramural Research Intramural Research ...

  14. From Ear to Brain

    ERIC Educational Resources Information Center

    Kimura, Doreen

    2011-01-01

    In this paper Doreen Kimura gives a personal history of the "right-ear effect" in dichotic listening. The focus is on the early ground-breaking papers, describing how she did the first dichotic listening studies relating the effects to brain asymmetry. The paper also gives a description of the visual half-field technique for lateralized stimulus

  15. D-2 dopamine receptor activation reduces free ( sup 3 H)arachidonate release induced by hypophysiotropic peptides in anterior pituitary cells

    SciTech Connect

    Canonico, P.L. )

    1989-09-01

    Dopamine reduces the stimulation of intracellular ({sup 3}H)arachidonate release produced by the two PRL-stimulating peptides angiotensin-II and TRH. This effect is concentration dependent and is mediated by stimulation of D-2 dopamine receptors. D-2 receptor agonists (bromocriptine, dihydroergocryptine, and dihydroergocristine) inhibit the release of fatty acid induced by angiotensin-II with a potency that parallels their ability to inhibit PRL release in vitro. Conversely, the selective D-2 receptor antagonist L-sulpiride completely prevents dopamine's effect, whereas SCH 23390 (a D-1 receptor antagonist) is ineffective. The inhibitory action of dopamine does not seem to be consequent to an action on the adenylate cyclase-cAMP system, as 8-bromo-cAMP (1 mM) does not affect either basal or dopamine-inhibited ({sup 3}H)arachidonate release. However, a 24-h pertussis toxin pretreatment significantly reduces the action of dopamine on fatty acid release. Collectively, these results suggest that D-2 dopamine receptor-mediated inhibition of intracellular ({sup 3}H)arachidonate release requires the action of a GTP-binding protein, but is not a consequence of an inhibitory action on cAMP levels.

  16. Pinna abnormalities and low-set ears

    MedlinePLUS

    Low-set ears; Microtia; "Lop" ear ... conditions: Abnormal folds or location of the pinna Low-set ears No opening to the ear canal ... Common conditions that can cause low-set and unusually formed ears ... conditions that can cause low-set and malformed ears include: ...

  17. Ear recognition: a complete system

    NASA Astrophysics Data System (ADS)

    Abaza, Ayman; Harrison, Mary Ann F.

    2013-05-01

    Ear Recognition has recently received significant attention in the literature. Even though current ear recognition systems have reached a certain level of maturity, their success is still limited. This paper presents an efficient complete ear-based biometric system that can process five frames/sec; Hence it can be used for surveillance applications. The ear detection is achieved using Haar features arranged in a cascaded Adaboost classifier. The feature extraction is based on dividing the ear image into several blocks from which Local Binary Pattern feature distributions are extracted. These feature distributions are then fused at the feature level to represent the original ear texture in the classification stage. The contribution of this paper is three fold: (i) Applying a new technique for ear feature extraction, and studying various optimization parameters for that technique; (ii) Presenting a practical ear recognition system and a detailed analysis about error propagation in that system; (iii) Studying the occlusion effect of several ear parts. Detailed experiments show that the proposed ear recognition system achieved better performance (94:34%) compared to other shape-based systems as Scale-invariant feature transform (67:92%). The proposed approach can also handle efficiently hair occlusion. Experimental results show that the proposed system can achieve about (78%) rank-1 identification, even in presence of 60% occlusion.

  18. Salicylate enables cochlear arachidonic-acid-sensitive NMDA receptor responses.

    PubMed

    Ruel, Jrme; Chabbert, Christian; Nouvian, Rgis; Bendris, Rim; Eybalin, Michel; Leger, Claude Louis; Bourien, Jrme; Mersel, Marcel; Puel, Jean-Luc

    2008-07-16

    Currently, many millions of people treated for various ailments receive high doses of salicylate. Consequently, understanding the mechanisms by which salicylate induces tinnitus is an important issue for the research community. Behavioral testing in rats have shown that tinnitus induced by salicylate or mefenamate (both cyclooxygenase blockers) are mediated by cochlear NMDA receptors. Here we report that the synapses between the sensory inner hair cells and the dendrites of the cochlear spiral ganglion neurons express NMDA receptors. Patch-clamp recordings and two-photon calcium imaging demonstrated that salicylate and arachidonate (a substrate of cyclooxygenase) enabled the calcium flux and the neural excitatory effects of NMDA on cochlear spiral ganglion neurons. Salicylate also increased the arachidonate content of the whole cochlea in vivo. Single-unit recordings of auditory nerve fibers in adult guinea pig confirmed the neural excitatory effect of salicylate and the blockade of this effect by NMDA antagonist. These results suggest that salicylate inhibits cochlear cyclooxygenase, which increased levels of arachidonate. The increased levels of arachidonate then act on NMDA receptors to enable NMDA responses to glutamate that inner hair cells spontaneously release. This new pharmacological profile of salicylate provides a molecular mechanism for the generation of tinnitus at the periphery of the auditory system. PMID:18632935

  19. EFFECTS OF PHOSGENE EXPOSURE ON LUNG ARACHIDONIC ACID METABOLISM

    EPA Science Inventory

    Phosgene is a pulmonary toxicant that can produce lung edema, bronchoconstriction, and immune suppression following an acute exposure. he response of the lung to phosgene inhalation may be mediated through alternations in the metabolism of arachidonic acid to the biologically pot...

  20. Tympanometry revealing middle ear pathology.

    PubMed

    Renvall, U; Holmquist, J

    1976-01-01

    In order to evaluate the usefulness of impedance audiometry as a screening method for school children, two different pilot studies were performed. The results indicated that impedance audiometry (tympanometry and stapedius reflex test) was more efficient than otoscopy and pure tone screening in the detection of ears with secretory otitis media (SOM). In order to gain some more experience, an extended study of 800 7-year-olds was performed. The results from this investigation showed 6.5% pathological values with pure tone screening, 13.5% pathological values with tympanometry and 32% elevated or nonelicitable stapedius reflexes. Analysis of our observations indicates that the stapedius reflex may be too sensitive a test to be used as a screening method. Tympanometry, however, is recommended as a complement to pure tone screening in screening of children. A 6-12 months follow-up was also performed on 357 ears in which an initial study had shown a middle ear pressure of less than or equal to -100 mm H2O. At the repeated test 20% had pathological pure tone screening, 40% had a middle ear pressure of less than or equal to -100 mm H2O, 57% had elevated or nonelicitable stapedius reflexes, and 14% had middle ear effusion. The high frequency of persisting abnormal middle ear pressure and effusion in these 357 ears suggests that a middle ear pressure of less than or equal to -100 mm H2O can be a predisposing factor for SOM. In an experimental study on human temporal bones it was demonstrated that the tympanogram preserves its original appearance when the water level is low in the middle ear, while a higher level gives rise to a pathological tympanogram. It is also demonstrated that there is a discrepancy between the tympanometrically, indirectly recorded middle ear pressure and the middle ear pressure as measured manometrically, directly from the middle ear. PMID:1267350

  1. The ear: Diagnostic imaging

    SciTech Connect

    Vignaud, J.; Jardin, C.; Rosen, L.

    1986-01-01

    This is an English translation of volume 17-1 of Traite de radiodiagnostic and represents a reasonably complete documentation of the diseases of the temporal bone that have imaging manifestations. The book begins with chapters on embryology, anatomy and radiography anatomy; it continues with blood supply and an overview of temporal bone pathology. Subsequent chapters cover malformations, trauma, infections, tumors, postoperative changes, glomus tumors, vertebasilar insufficiency, and facial nerve canal lesions. A final chapter demonstrates and discusses magnetic resonance images of the ear and cerebellopontine angle.

  2. Red Ear Syndrome.

    PubMed

    Raieli, V; Compagno, A; D'Amelio, M

    2016-03-01

    The Red ear syndrome (RES) is an intriguing syndrome originally described for the first time nearly 20years ago. RES is characterized by unilateral/bilateral episodes of pain and burning sensation of the ear, associated with ipsilateral erythema. RES episodes are indeed isolated in some patients, but they can occur in association with primary headaches, including in particular migraine in the developmental age. Although the underlying pathophysiological mechanisms are still uncertain, in the recent years the described comorbidities have aroused increasing interest because of possible clinical implications. Moreover, RES seems to be more often associated with clinical features of migraine partially provoked by the involvement of the parasympathetic system. This clinical association has shed new light on the pathophysiology of RES, supporting the hypothesis of a shared pathophysiological background, for example, through the activation of the trigeminal autonomic reflex. Current therapies of RES will be also discussed. Finally, we will resume the more controversial aspects of this relatively new and probably underestimated neurological syndrome. PMID:26879877

  3. [MIDDLE EAR INFECTION].

    PubMed

    Mari?i?, Martina; Bonjak, Zrinka; Branica, Sre?ko

    2015-01-01

    Middle ear infection is one of the most common childhood infections and the leading reason for antibiotic prescriptions. Although the etiological diagnosis is rarely discovered, successful identification of pathogens depends on properly collected sample, chosen method and microbiological analysis made on time. The most common bacterial pathogen is Streptococcus pneumoniae. Others include Haemophilus influenzae, Moraxella catarrhalis and Pseudomonas aeruginosa, known as the most common bacterial pathogen of chronic inflamations. Viral or polimicrobial upper respiratory tract infections often precede this infection. Pneumococcal conjugate vaccines given during infancy decrease rates of acute middle ear inflammation. It is a self-limited disease with rare complications. The best treatment is watchful waiting for two days followed by amoxicillin during 7 days, only if it is necessary. If there is resistance, then combination of amoxicillin and beta lactamase inhibitor is second line. The best choice for patients allergic to penicillin are macrolides. Antibiotic treatment has contributed to frequent relapses and increase of multi-drug resistant pathogens by permitting their colonization, which eliminates protective nasopharyngeal flora. PMID:26749955

  4. Otoscopic exam of the ear (image)

    MedlinePLUS

    ... intrument which is used to look into the ear canal. The ear speculum (a cone-shaped viewing piece of the otoscope) is slowly inserted into the ear canal while looking into the otoscope. The speculum ...

  5. Wax blockage in the ear (image)

    MedlinePLUS

    The ear canal is lined with hair follicles and glands that produce a waxy oil called cerumen. Sometimes the ... wax than can be easily excreted out the ear. This extra wax may harden within the ear ...

  6. Middle ear infection (otitis media) (image)

    MedlinePLUS

    ... is an inflammation and/or infection of the middle ear. Acute otitis media (acute ear infection) occurs ... or viral infection of the fluid of the middle ear, which causes production of fluid or pus. ...

  7. Ear Reconstruction in Young Children.

    PubMed

    Reinisch, John

    2015-12-01

    The use of a porous high-density polyethylene ear implant, rather than a costal cartilage framework, allows ear reconstruction in young children before they enter school. The fact that the growth of the normal ear matures early allows for good symmetry. If the implant is covered completely with a large, well-vascularized superficial parietal fascia flap and appropriately color-matched skin, an ear with excellent projection and definition can be obtained with minimal complications and long-term viability. Ear reconstruction in young children is preferred by the author because the necessary fascial flap coverage is thinner, easier to harvest than in older patients, and can be done in a single outpatient procedure with minimal discomfort or psychological trauma. PMID:26667634

  8. Surgical correction of constricted ear combined with Stahl's ear.

    PubMed

    Bi, Ye; Lin, Lin; Yang, Qinhua; Pan, Bo; Zhao, Yanyong; He, Leren; Jiang, Haiyue

    2015-07-01

    Constricted ear combined with Stahl's ear is a rare ear deformity, which is a kind of complex congenital auricular deformity. From 1 January 2007 to 1 January 2014, 19 patients with constricted ear combined with Stahl's ear (Spock ear) were enrolled in this study, most of which were unilaterally deformed. To correct the deformity, a double Z-shaped skin incision was made on the posterior side of the auricle, with the entire layer of cartilage cut parallel to the helix traversing the third crus to form a fan-shaped cartilage flap. The superior crura of the antihelix were shaped by the folding cartilage rim. The cartilage of the abnormal third crus was made part of the new superior crura of antihelix, and the third crus was eliminated. The postoperative aesthetic assessment of the reshaped auricle was graded by both doctors and patients (or their parents). Out of the 19 patients, the number of satisfying cases of the symmetry, helix stretch, elimination of the third crus, the cranioauricular angle, and the substructure of the reshaped ears was 14 (nine excellent and five good), 16 (six excellent and 10 good), 17 (eight excellent and nine good), 15 (five excellent and 10 good), and 13 (two excellent and 11 good), respectively. With a maximum of a 90-month follow-up, no complication was observed. The results of the study suggested that this rare deformity could be corrected by appropriate surgical treatment, with a satisfied postoperative appearance. PMID:25921912

  9. Identification of a novel class of endoperoxides from arachidonate autoxidation.

    PubMed

    Yin, Huiyong; Morrow, Jason D; Porter, Ned A

    2004-01-30

    Free radical-initiated lipid autoxidation in low density lipoprotein (LDL) has been implicated in the pathogenesis of atherosclerosis. Oxidation of the lipid components of LDL leads to a complex mixture of hydroperoxides, bicyclic endoperoxides, monocyclic peroxides, and serial cyclic peroxides. The oxidation compounds and/or their decomposition products can modify protein components, which may lead to various diseases. A novel class of peroxides (termed dioxolane-isoprostanes) having a bicyclic endoperoxide moiety characteristic of the isoprostanes and a dioxolane peroxide functionality in the same molecule was identified in the product mixture formed from in vitro autoxidation of cholesteryl arachidonate. The same products are also detected in in vitro oxidized LDL. Various mass spectrometric techniques have been applied to characterize these new peroxides. The structure of these compounds has also been confirmed by independent synthesis. We reason, based on the free radical mechanism of the transformation, that only the 12- and 8-peroxyl radicals (those leading to 12-HPETE and 8-HPETE) of arachidonate can form these new peroxides. We also suggest that the formation of these peroxides provides a rationale to explain the fact that 5- and 15-series isoprostanes are formed in preference to 8- and 12-series. Furthermore, series of other isoprostanes, such as dioxolane A(2), D(2), E(2), etc., can be derived from the dioxolane-isoprostane peroxides. These findings offer further insights into the oxidation products of arachidonate and the opportunity to study their potential biological relevance. PMID:14594817

  10. Middle Ear Infections and Ear Tube Surgery (For Parents)

    MedlinePLUS

    ... them because of environmental and lifestyle factors (like attendance at a group childcare, secondhand tobacco smoke exposure, ... Disorder (ANSD) Preparing Your Child for Surgery Hearing Evaluation in Children Anesthesia Basics Ears Eardrum Injuries Middle ...

  11. [Inner ear cochlear processes].

    PubMed

    Livshits, M S

    1995-01-01

    The processes accompanying the propagation across the basilar membrane (BM) of waves from a wide-band sound signal have been analyzed by physical methods. Particular emphasis in placed on the fact that BM is a low frequency filter. The characteristics of wave envelope from each of the sinusoidal components of the signal are given. The use of a simple mechanical model makes it possible to explain an initial increase in these envelopes. The steep slope of the envelope in its terminal part is explained in terms of the lighthill hydrodynamic model of cochlea. This provides a theoretical basis for adequate description of the periphery of the ear analyzer, with allowance for the active role of external auditory hair cells (EHC). Further research is needed to solve the problem completely. This is dictated by the complexity of the oscillatory system (BM in the region of the critical layer of cochlea plus EHC) and by its interaction with the autoregulation system in the air analyzer, which is described elsewhere. PMID:7662742

  12. Taking Care of Your Ears

    MedlinePLUS

    ... ll also want to prevent infections in your newly pierced ears. Wash your hands before touching your ... The Nemours Foundation, iStock, Getty Images, Corbis, Veer, Science Photo Library, Science Source Images, Shutterstock, and Clipart. ...

  13. Ototoxicity (Ear Poisoning) (For Parents)

    MedlinePLUS

    ... Speech or Language Development Speech-Language Therapy Physical Therapy Hearing Evaluation in Children The Danger of Antibiotic Overuse Eardrum Injuries Hearing Impairment: Advice From Kristin What's Hearing Loss? Can Loud Music Hurt My Ears? Going to the Audiologist Hearing ...

  14. Ototoxicity (Ear Poisoning) (For Parents)

    MedlinePLUS

    ... KidsHealth in the Classroom What Other Parents Are Reading Signing Kids Up for Sports 15-Minute Meal: ... from auditory or listening therapy and speech (lip) reading. Those with serious damage to the inner ear ...

  15. 21 CFR 870.2710 - Ear oximeter.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear oximeter. 870.2710 Section 870.2710 Food and... CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An ear... ear. The amount of reflected or scattered light as indicated by this device is used to measure...

  16. 21 CFR 870.2710 - Ear oximeter.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear oximeter. 870.2710 Section 870.2710 Food and... CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An ear... ear. The amount of reflected or scattered light as indicated by this device is used to measure...

  17. 21 CFR 870.2710 - Ear oximeter.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear oximeter. 870.2710 Section 870.2710 Food and... CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An ear... ear. The amount of reflected or scattered light as indicated by this device is used to measure...

  18. 21 CFR 870.2710 - Ear oximeter.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear oximeter. 870.2710 Section 870.2710 Food and... CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An ear... ear. The amount of reflected or scattered light as indicated by this device is used to measure...

  19. 21 CFR 870.2710 - Ear oximeter.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear oximeter. 870.2710 Section 870.2710 Food and... CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An ear... ear. The amount of reflected or scattered light as indicated by this device is used to measure...

  20. The visible ear surgery simulator.

    PubMed

    Trier, Peter; Noe, Karsten Østergaard; Sørensen, Mads Sølvsten; Mosegaard, Jesper

    2008-01-01

    This paper presents a real-time computer simulation of surgical procedures in the ear, in which a surgeon drills into the temporal bone to gain access to the middle or inner ear. The purpose of this simulator is to support development of anatomical insight and training of drilling skills for both medical students and experienced otologists. The key contributions in this application are the visualization and interaction models in the context of ear surgical simulation. The visualization is based on an existing data set, "The Visible Ear", containing a unique volume depicting the inner ear in natural colours. The applied visualization is based on GPU ray casting, allowing high quality and flexible volume rendering using modern graphics card. In connection with the visualization model, different methods for optimizing the GPU ray casting procedure are presented, along with a method for combining polygon based graphics with volume rendering. In addition, different light models are presented that contribute to a realistic rendering of the different parts of the inner ear. To achieve a physically plausible drilling experience, a Phantom Omni force feedback device is utilized. The applied interaction model facilitates a realistic user experience of the response forces from the drilling tool. PMID:18391361

  1. Proliferation-dependent changes in release of arachidonic acid from endothelial cells.

    PubMed Central

    Whatley, R E; Satoh, K; Zimmerman, G A; McIntyre, T M; Prescott, S M

    1994-01-01

    Stimulation of endothelial cells resulted in release of arachidonic acid from phospholipids. The magnitude of this response decreased as the cells became confluent and the change coincided with a decrease in the percentage of cells in growth phases (G2+M); this was not a consequence of time in culture or a factor in the growth medium. Preconfluent cells released approximately 30% of arachidonic acid; confluent cells released only 6%. The decreasing release of arachidonic acid was demonstrated using metabolic labeling, mass measurements of arachidonic acid, and measurement of PGI2. The decrease was not due to a changing pool of arachidonic acid, and mass measurements showed no depletion of arachidonic acid. Release from each phospholipid and from each phospholipid class decreased with confluence. Conversion of confluent cells to the proliferative phenotype by mechanical wounding of the monolayer caused increased release of arachidonic acid. Potential mechanisms for these changes were investigated using assays of phospholipase activity. Phospholipase A2 activity changed in concert with the alteration in release, a consequence of changes in phosphorylation of the enzyme. The increased release of arachidonic acid from preconfluent, actively dividing cells may have important physiologic implications and may help elucidate mechanisms regulating release of arachidonic acid. Images PMID:7962534

  2. Attachment of substrate metabolite to prostaglandin H synthase upon reaction with arachidonic acid

    SciTech Connect

    Kulmacz, R.J.

    1987-10-29

    Prostaglandin H synthase was incubated with (/sup 14/C)arachidonate and then analyzed by polyacrylamide gel electrophoresis under denaturing conditions and by high pressure liquid chromatography. A maximum of 1 mol of arachidonate metabolite was found to become attached per mol of synthase subunit in a time-dependent process that was much slower than the rate of self-catalyzed inactivation of the cyclooxygenase activity. Incubation of a mixture of the synthase and ovalbumin with (/sup 14/C)arachidonate resulted in a selective attachment of radiolabel to the synthase. These results suggest the presence of a single site on the synthase that is susceptible to reaction with an arachidonate metabolite.

  3. Arachidonate epoxygenase: identification of epoxyeicosatrienoic acids in rabbit kidney.

    PubMed

    Falck, J R; Schueler, V J; Jacobson, H R; Siddhanta, A K; Pramanik, B; Capdevila, J

    1987-07-01

    Epoxyeicosatrienoic acids were isolated and purified from female rabbit kidneys. They were identified as a group, prior to resolution, by packed column gas-liquid chromatography-mass spectroscopic techniques as their methyl esters as well as their trimethylsilyl bromohydrin methyl esters. Initial capillary gas-liquid chromatography-mass spectral analysis of the corresponding hydrogenated pentafluorobenzyl esters revealed the presence of the 8,9- and 14,15-epoxyeicosatrienoate regioisomers. These results, in conjunction with the documented in vitro biological activities of the arachidonate epoxygenase metabolites, suggest a role for them in renal function. PMID:3625040

  4. Arachidonic acid enhances reproduction in Daphnia magna and mitigates changes in sex ratios induced by pyriproxyfen.

    PubMed

    Ginjupalli, Gautam K; Gerard, Patrick D; Baldwin, William S

    2015-03-01

    Arachidonic acid is 1 of only 2 unsaturated fatty acids retained in the ovaries of crustaceans and an inhibitor of HR97g, a nuclear receptor expressed in adult ovaries. The authors hypothesized that, as a key fatty acid, arachidonic acid may be associated with reproduction and potentially environmental sex determination in Daphnia. Reproduction assays with arachidonic acid indicate that it alters female:male sex ratios by increasing female production. This reproductive effect only occurred during a restricted Pseudokirchneriella subcapitata diet. Next, the authors tested whether enriching a poorer algal diet (Chlorella vulgaris) with arachidonic acid enhances overall reproduction and sex ratios. Arachidonic acid enrichment of a C. vulgaris diet also enhances fecundity at 1.0 µM and 4.0 µM by 30% to 40% in the presence and absence of pyriproxyfen. This indicates that arachidonic acid is crucial in reproduction regardless of environmental sex determination. Furthermore, the data indicate that P. subcapitata may provide a threshold concentration of arachidonic acid needed for reproduction. Diet-switch experiments from P. subcapitata to C. vulgaris mitigate some, but not all, of arachidonic acid's effects when compared with a C. vulgaris-only diet, suggesting that some arachidonic acid provided by P. subcapitata is retained. In summary, arachidonic acid supplementation increases reproduction and represses pyriproxyfen-induced environmental sex determination in D. magna in restricted diets. A diet rich in arachidonic acid may provide protection from some reproductive toxicants such as the juvenile hormone agonist pyriproxyfen. Environ Toxicol Chem 2015;34:527-535. © 2014 SETAC. PMID:25393616

  5. 3D Printed Bionic Ears

    PubMed Central

    Mannoor, Manu S.; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A.; Soboyejo, Winston O.; Verma, Naveen; Gracias, David H.; McAlpine, Michael C.

    2013-01-01

    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the precise anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing. PMID:23635097

  6. Ear disorders in scuba divers.

    PubMed

    Azizi, M H

    2011-01-01

    History of underwater diving dates back to antiquity. Breath-hold technique in diving was known to the ancient nations. However, deep diving progressed only in the early decades of the 19th century as the result of advancements in efficient underwater technologies which subsequently led to invention of sophisticated sets of scuba diving in the 20th century. Currently, diving is performed for various purposes including commercial, recreational, military, underwater construction, oil industry, underwater archeology and scientific assessment of marine life. By increasing popularity of underwater diving, dive-related medical conditions gradually became more evident and created a new challenge for the health care professionals, so that eventually, a specialty the so-called "diving medicine" was established. Most of the diving-associated disorders appear in the head and neck. The most common of all occupational disorders associated with diving are otologic diseases. External otitis has been reported as the most common otolaryngologic problem in underwater divers. Exostosis of the external ear canal may be formed in divers as the result of prolonged diving in cold waters. Other disorders of the ear and paranasal sinuses in underwater divers are caused by barometric pressure change (i.e., barotraumas), and to a lesser extent by decompression sickness. Barotrauma of the middle ear is the most prevalent barotrauma in divers. The inner ear barotraumas, though important, is less common. The present paper is a brief overview of diving-related ear disorders particularly in scuba divers. PMID:23022815

  7. 3D printed bionic ears.

    PubMed

    Mannoor, Manu S; Jiang, Ziwen; James, Teena; Kong, Yong Lin; Malatesta, Karen A; Soboyejo, Winston O; Verma, Naveen; Gracias, David H; McAlpine, Michael C

    2013-06-12

    The ability to three-dimensionally interweave biological tissue with functional electronics could enable the creation of bionic organs possessing enhanced functionalities over their human counterparts. Conventional electronic devices are inherently two-dimensional, preventing seamless multidimensional integration with synthetic biology, as the processes and materials are very different. Here, we present a novel strategy for overcoming these difficulties via additive manufacturing of biological cells with structural and nanoparticle derived electronic elements. As a proof of concept, we generated a bionic ear via 3D printing of a cell-seeded hydrogel matrix in the anatomic geometry of a human ear, along with an intertwined conducting polymer consisting of infused silver nanoparticles. This allowed for in vitro culturing of cartilage tissue around an inductive coil antenna in the ear, which subsequently enables readout of inductively-coupled signals from cochlea-shaped electrodes. The printed ear exhibits enhanced auditory sensing for radio frequency reception, and complementary left and right ears can listen to stereo audio music. Overall, our approach suggests a means to intricately merge biologic and nanoelectronic functionalities via 3D printing. PMID:23635097

  8. Ear problems and injuries in athletes.

    PubMed

    Cassaday, Kacie; Vazquez, Gerardo; Wright, Justin M

    2014-01-01

    The ear is an unique organ--the principal structure involved in both hearing and balance. Although not common, problems with the ear may be encountered in specific sporting populations. Common conditions affecting the ear in the athlete include otitis externa, an infection of the external ear; external auditory canal exostoses, or abnormal bony growths in the canal; and otitis media, an infection of the middle ear. Given its position on the head, the ear is subject to trauma, often resulting in an auricular hematoma. Divers, due to pressure changes on descent and ascent, are subject to both ear barotrauma and ear decompression sickness. This article will discuss recognition, treatment, and prevention of these conditions affecting the ear in the athlete. PMID:24412886

  9. Altered arachidonic acid metabolism and platelet size in atopic subjects

    SciTech Connect

    Audera, C.; Rocklin, R.; Vaillancourt, R.; Jakubowski, J.A.; Deykin, D.

    1988-03-01

    The release and metabolism of endogenous arachidonic acid (AA) in physiologically activated platelets obtained from 11 atopic patients with allergic rhinitis and/or asthma was compared to that of sex- and age-matched nonatopic controls. Prelabeled (/sup 3/H)AA platelets were stimulated with thrombin or collagen and the amount of free (/sup 3/H)AA and radiolabeled metabolites released were measured by high-performance liquid chromatography. The results obtained indicate that although the incorporation of (/sup 3/H)AA into platelet phospholipids and total release of /sup 3/H-radioactivity upon stimulation were comparable in the two groups, the percentage of /sup 3/H-radioactivity released from platelets as free AA was significantly lower (P less than 0.01) in the atopic group. The reduction in free (/sup 3/H)AA was accompanied by an increase (P less than 0.01) in the percentage of /sup 3/H-radioactivity released as cyclooxygenase products in atopic platelets (compared to nonatopic cells) after stimulation with 10 and 25 micrograms/ml collagen. The amount of platelet lipoxygenase product released was comparable between the two groups. Although the blood platelet counts were similar, the mean platelet volume was statistically higher (P less than 0.01) in the atopic group. These results indicate that arachidonic acid metabolism in atopic platelets is altered, the pathophysiological significance of which remains to be clarified.

  10. Cannabinoids influence lipid-arachidonic acid pathways in schizophrenia.

    PubMed

    Smesny, Stefan; Rosburg, Timm; Baur, Kati; Rudolph, Nicole; Sauer, Heinrich

    2007-10-01

    Increasing evidence suggests modulating effects of cannabinoids on time of onset, severity, and outcome of schizophrenia. Efforts to discover the underlying pathomechanism have led to the assumption of gene x environment interactions, including premorbid genetical vulnerability and worsening effects of continuing cannabis use. The objective of this cross-sectional study is to investigate the relationship between delta-9-tetrahydrocannabinol intake and niacin sensitivity in schizophrenia patients and healthy controls. Intensity of niacin skin flushing, indicating disturbed prostaglandin-mediated processes, was used as peripheral marker of lipid-arachidonic acid pathways and investigated in cannabis-consuming and nonconsuming schizophrenia patients and in healthy controls. Methylnicotinate was applied in three concentrations onto the forearm skin. Flush response was assessed in 3-min intervals over 15 min using optical reflection spectroscopy. In controls, skin flushing was significantly decreased in cannabis-consuming as compared to nonconsuming individuals. When comparing the nonconsuming subgroups, patients showed significantly decreased flush response. The populations as a whole (patients and controls) showed an inverse association between skin flushing and sum scores of Symptom Check List 90-R. Results demonstrate an impact of long-term cannabis use on lipid-arachidonic acid pathways. Considering pre-existing vulnerability of lipid metabolism in schizophrenia, observed effects of cannabis use support the notion of a gene x environment interaction. PMID:17314920

  11. Oxygenation products of arachidonic acid: third messengers for insulin release.

    PubMed

    Metz, S A; Fujimoto, W Y; Robertson, R P

    1984-09-01

    Although an association between membrane phospholipid turnover and exocytotic hormone release has long been recognized, a causal relationship has not been firmly established. Recent studies suggest that glucose (and probably other insulin secretagogues) activates phospholipases and thereby releases membrane-bound arachidonic acid (AA). AA is then converted through islet 12-lipoxygenase to mediators or modulators of insulin release (tentatively identified as peroxides and epoxides of arachidonate). These products may be critical links in stimulus-secretion coupling, since blockade of either AA release or lipoxygenation abrogates insulin release induced by glucose and many other (but not all) stimuli. Cogeneration of prostaglandins from AA through the cyclooxygenase pathway may directly or indirectly modulate the formation and/or effect of lipoxygenase products. A critical role for lipoxygenase products (and possibly metabolites of AA synthesized by other pathways, such as P-450-dependent monooxygenases) may extend to many secretory cells in addition to pancreatic beta cells. The phasic release of AA described in many cells could explain the biphasic pattern of insulin release induced by glucose. Since some phospholipases and lipoxygenases are Ca++ activated, the release of AA in conjunction with its oxygenation appears to be a concerted system generating "third messengers" for hormone release. PMID:6432880

  12. Tuning in the bullfrog ear.

    PubMed Central

    Lewis, E R

    1988-01-01

    When electrical resonances were observed in acoustic sensory cells of lower vertebrates, the hearing research community was presented with the exciting possibility that tuning in the ears of those animals might be explained directly in terms of familiar molecular devices. It is reported here that in the frog sacculus, where electrical resonances have been observed in isolated hair cells, the effects of those resonances are completely obscured in the tuning properties of the sacculus in the intact ear. This observation has important implications not only for students of the ear, but for reductionist biologists in general. All of the dynamic properties of a system of connected, bidirectional processes are consequences of all of those processes at once; in such a system, the properties of an experimentally isolated subsystem may be totally obscured in the operation of the system as a whole. PMID:3258166

  13. Development of the inner ear.

    PubMed

    Whitfield, Tanya T

    2015-06-01

    The vertebrate inner ear is a sensory organ of exquisite design and sensitivity. It responds to sound, gravity and movement, serving both auditory (hearing) and vestibular (balance) functions. Almost all cell types of the inner ear, including sensory hair cells, sensory neurons, secretory cells and supporting cells, derive from the otic placode, one of the several ectodermal thickenings that arise around the edge of the anterior neural plate in the early embryo. The developmental patterning mechanisms that underlie formation of the inner ear from the otic placode are varied and complex, involving the reiterative use of familiar signalling pathways, together with roles for transcription factors, transmembrane proteins, and extracellular matrix components. In this review, I have selected highlights that illustrate just a few of the many recent discoveries relating to the development of this fascinating organ system. PMID:25796080

  14. Arachidonic Acid Enhances Turnover of the Dermal Skeleton: Studies on Zebrafish Scales

    PubMed Central

    de Vrieze, Erik; Moren, Mari; Metz, Juriaan R.; Flik, Gert; Lie, Kai Kristoffer

    2014-01-01

    In fish nutrition, the ratio between omega-3 and omega-6 poly-unsaturated fatty acids influences skeletal development. Supplementation of fish oils with vegetable oils increases the content of omega-6 fatty acids, such as arachidonic acid in the diet. Arachidonic acid is metabolized by cyclooxygenases to prostaglandin E2, an eicosanoid with effects on bone formation and remodeling. To elucidate effects of poly-unsaturated fatty acids on developing and existing skeletal tissues, zebrafish (Danio rerio) were fed (micro-) diets low and high in arachidonic acid content. Elasmoid scales, dermal skeletal plates, are ideal to study skeletal metabolism in zebrafish and were exploited in the present study. The fatty acid profile resulting from a high arachidonic acid diet induced mild but significant increase in matrix resorption in ontogenetic scales of adult zebrafish. Arachidonic acid affected scale regeneration (following removal of ontogenetic scales): mineral deposition was altered and both gene expression and enzymatic matrix metalloproteinase activity changed towards enhanced osteoclastic activity. Arachidonic acid also clearly stimulates matrix metalloproteinase activity in vitro, which implies that resorptive effects of arachidonic acid are mediated by matrix metalloproteinases. The gene expression profile further suggests that arachidonic acid increases maturation rate of the regenerating scale; in other words, enhances turnover. The zebrafish scale is an excellent model to study how and which fatty acids affect skeletal formation. PMID:24586706

  15. Classification and diagnosis of ear malformations

    PubMed Central

    Bartel-Friedrich, Sylva; Wulke, Cornelia

    2008-01-01

    In the ENT region 50% of the malformations affect the ear. Malformations of the outer and middle ear are predominantly unilateral (ca. 70-90%) and mostly involve the right ear. Inner ear malformations can be unilateral or bilateral. The incidence of ear malformations is approximately 1 in 3800 newborns. Ear malformations may be genetic (associated with syndromes or not, with family history, spontaneous mutations) or acquired in nature. Malformations can affect the outer ear (pinna and external auditory canal, EAC), middle ear and inner ear, not infrequently in combination. Formal classification is advisable in order to be able to predict the prognosis and compare treatment schedules. Various classifications have been proposed: pinna and EAC malformations according to Weerda [1], middle ear malformations according to Kösling [2], and inner ear malformations according to Jackler [3], [4], to Marangos [5] and to Sennaroglu [6]. Additionally, we describe Altmann’s classification of atresia auris congenita [7] and the Siegert-Mayer-Weerda score [8] for EAC and middle ear malformations, systems of great practicability that are in widespread clinical use. The diagnostic steps include clinical examination, audiological testing, genetic analysis and, especially, CT and MRI. These imaging methods are most usefully employed in combination. Precise description of the malformations by means of CT and MRI is indispensable for the planning and successful outcome of operative ear reconstruction and rehabilitation procedures, including cochlear implantation. PMID:22073081

  16. Attenuation of acid induced oesophagitis in VR?1 deficient mice

    PubMed Central

    Fujino, K; de la Fuente, S G; Takami, Y; Takahashi, T; Mantyh, C R

    2006-01-01

    Background and aims Activation of the vanilloid receptor subtype 1 (VR?1) results in release of proinflammatory peptides which initiate an inflammatory cascade known as neurogenic inflammation. We investigated its role in an acute model of surgically induced oesophagitis. Methods Oesophagitis was induced by pyloric ligation in wild?type and VR?1 deficient mice. A subset of animals were administered the VR?1 antagonist capsazepine, famotidine, or omeprazole one hour before surgery. Five hours after surgery, myeloperoxidase activity (MPO), histological damage scores, intragastric pH, and immunocytochemical analysis of substance P (SP) receptor endocytosis were determined. Results Oesophagitis induced knockout mice exhibited significantly lower levels of MPO activity, histological damage scores, and SP receptor endocytosis than wild?type mice. Inflammatory parameters were significantly reduced by acid inhibition and capsazepine in wild?type mice. Conclusions We conclude that acute acid induced oesophagitis is reduced in animals lacking VR?1. This suggests that acid induced oesophagitis may act through VR?1 and that inhibition of the receptor may reduce inflammation. PMID:16091555

  17. Physiological functioning of the ear and masking

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The physiological functions of the ear and the role masking plays in speech communication are examined. Topics under investigation include sound analysis of the ear, the aural reflex, and various types of noise masking.

  18. Inner Ear Drug Delivery for Auditory Applications

    PubMed Central

    Swan, Erin E. Leary; Mescher, Mark J.; Sewell, William F.; Tao, Sarah L.; Borenstein, Jeffrey T.

    2008-01-01

    Many inner ear disorders cannot be adequately treated by systemic drug delivery. A blood-cochlear barrier exists, similar physiologically to the blood-brain barrier, which limits the concentration and size of molecules able to leave the circulation and gain access to the cells of the inner ear. However, research in novel therapeutics and delivery systems has led to significant progress in the development of local methods of drug delivery to the inner ear. Intratympanic approaches, which deliver therapeutics to the middle ear, rely on permeation through tissue for access to the structures of the inner ear, whereas intracochlear methods are able to directly insert drugs into the inner ear. Innovative drug delivery systems to treat various inner ear ailments such as ototoxicity, sudden sensorineural hearing loss, autoimmune inner ear disease, and for preserving neurons and regenerating sensory cells are being explored. PMID:18848590

  19. Mechanics of the frog ear

    PubMed Central

    van Dijk, Pim; Mason, Matthew J.; Schoffelen, Richard L. M.; Narins, Peter M.; Meenderink, Sebastiaan W. F.

    2010-01-01

    The frog inner ear contains three regions that are sensitive to airborne sound and which are functionally distinct. (1) The responses of nerve fibres innervating the low-frequency, rostral part of the amphibian papilla (AP) are complex. Electrical tuning of hair cells presumably contributes to the frequency selectivity of these responses. (2) The caudal part of the AP covers the mid-frequency portion of the frog's auditory range. It shares the ability to generate both evoked and spontaneous otoacoustic emissions with the mammalian cochlea and other vertebrate ears. (3) The basilar papilla functions mainly as a single auditory filter. Its simple anatomy and function provide a model system for testing hypotheses concerning emission generation. Group delays of stimulus frequency otoacoustic emissions (SFOAEs) from the basilar papilla are accounted for by assuming that they result from forward and reverse transmission through the middle ear, a mechanical delay due to tectorial membrane filtering and a rapid forward and reverse propagation through the inner ear fluids, with negligible delay. PMID:20149854

  20. Reconstruction of middle ear malformations

    PubMed Central

    Schwager, Konrad

    2008-01-01

    Malformations of the middle ear are classified as minor and major malformations. Minor malformations appear with regular external auditory canal, tympanic membrane and aerated middle ear space. The conducting hearing loss is due to fixation or interruption of the ossicular chain. The treatment is surgical, following the rules of ossiculoplasty and stapes surgery. In major malformations (congenital aural atresia) there is no external auditory canal and a deformed or missing pinna. The mastoid and the middle ear space may be underdevelopped, the ossicular chain is dysplastic. Surgical therapy is possible in patients with good aeration of the temporal bone, existing windows, a near normal positioned facial nerve and a mobile ossicular chain. Plastic and reconstructive surgery of the pinna should proceed the reconstruction of the external auditory canal and middle ear. In cases of good prognosis unilateral aural atresia can be approached already in childhood. In patients with high risk of surgical failure, bone anchored hearing aids are the treatment of choice. Recent reports of implantable hearing devices may be discussed as an alternative treatment for selected patients. PMID:22073077

  1. The caecilian ear: further observations.

    PubMed

    Wever, E G; Gans, C

    1976-10-01

    The structure of the ear is examined in two species of caecilians, Ichthyophis glutinosus and I. orthoplicatus, and the sensitivity to aerial sounds is assessed in terms of the electrical potentials of the cochlea. The results are in general agreement with previous reports on other caecilian species. PMID:1068485

  2. Pediatric Obesity and Ear, Nose, and Throat Disorders

    MedlinePLUS

    ... an ENT Doctor Near You Pediatric Obesity and Ear, Nose, and Throat Disorders Pediatric Obesity and Ear, ... all children be regularly screened for snoring. Middle ear infections Acute otitis media (AOM) and chronic ear ...

  3. Normative inner ear volumetric measurements.

    PubMed

    Teixido, Michael T; Kirkilas, Gary; Seymour, Peter; Sem, Kanik; Iaia, Alberto; Sabra, Omar; Isildak, Huseyin

    2015-01-01

    In the current study, we attempted to determine normative inner ear volumetric measurements generated from three-dimensional computed tomography (CT) images. In addition, we investigated a correlation between the axial length and the volume of the labyrinth and discussed clinical outcomes of this correlation. Amira 5.2.2 software was used to create three-dimensional isosurface images of the human labyrinth using two-dimensional CT images from 35 anatomically normal patients. With the three-dimensional labyrinths, complete dimensional analysis was performed to gain insight into both the volume and the greatest axial length of the inner ear. Paired t test and Pearson correlation were used. Our volume of the inner ear inquiry reported a mean volume of 221.5 with SD of 24.3 ?L (0.228 ?L for males and 0.218 ?L for females). The length showed a mean of 1.713 cm with SD of 0.064 cm (1.753 cm for males and 1.695 cm for females). The length was used to estimate the volume, and the estimates were within 10% of the measured volume 74.3% of the time. Normative volumetric measurements of the inner ear can be obtained by using three-dimensional CT Imaging by Amira 5.2.2 software. There was a statistically significant positive correlation between the axial length of the labyrinth and the volume of the labyrinth. The axial length of the labyrinth could be used to estimate the volume of the labyrinth, which may be clinically important to estimate the concentration of the drug distributed in the inner ear. PMID:25490572

  4. Immunologic Disorders of the Inner Ear.

    ERIC Educational Resources Information Center

    Kinney, William C.; Hughes, Gordon B.

    1997-01-01

    Immune inner ear disease represents a series of immune system mediated problems that can present with hearing loss, dizziness, or both. The etiology, presentation, testing, and treatment of primary immune inner ear disease is discussed. A review of secondary immune inner ear disease is presented for comparison. (Contains references.) (Author/CR)

  5. Can Loud Music Hurt My Ears?

    MedlinePLUS

    ... Snowboarding, Skating Crushes What's a Booger? Can Loud Music Hurt My Ears? KidsHealth > For Kids > Can Loud Music Hurt My Ears? Print A A A Text ... up? Oh! You want to know if loud music can hurt your ears . Are you asking because ...

  6. 21 CFR 878.3590 - Ear prosthesis.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and... GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An ear prosthesis is a silicone rubber solid device intended to be implanted to reconstruct the...

  7. 21 CFR 878.3590 - Ear prosthesis.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and... GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An ear prosthesis is a silicone rubber solid device intended to be implanted to reconstruct the...

  8. 21 CFR 878.3590 - Ear prosthesis.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and... GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An ear prosthesis is a silicone rubber solid device intended to be implanted to reconstruct the...

  9. 21 CFR 878.3590 - Ear prosthesis.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and... GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An ear prosthesis is a silicone rubber solid device intended to be implanted to reconstruct the...

  10. 21 CFR 878.3590 - Ear prosthesis.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear prosthesis. 878.3590 Section 878.3590 Food and... GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification. An ear prosthesis is a silicone rubber solid device intended to be implanted to reconstruct the...

  11. Can Loud Music Hurt My Ears?

    MedlinePLUS

    ... What's a Booger? Can Loud Music Hurt My Ears? KidsHealth > For Kids > Can Loud Music Hurt My Ears? Print A A A Text Size en espaol ... to know if loud music can hurt your ears . Are you asking because you like to put ...

  12. Hyperalgesic properties of 15-lipoxygenase products of arachidonic acid.

    PubMed Central

    Levine, J D; Lam, D; Taiwo, Y O; Donatoni, P; Goetzl, E J

    1986-01-01

    Induction of hyperalgesia by leukotriene B4 (LTB4), a potent chemotactic factor for polymorphonuclear leukocytes (PMNLs), depends on the generation by cutaneous PMNLs of mediators that are probably derived from the 15-lipoxygenation of arachidonic acid. The capacity of dihydroxyeicosatetraenoic acid (diHETE) products of the 15-lipoxygenation of arachidonic acid in PMNL to elicit hyperalgesia was evaluated by assessing the effects of intradermal injection of synthetic diHETEs on the pressure nociceptive threshold in rats. (8R,15S)-Dihydroxyeicosa-(5E-9,11,13Z)-tetraenoic acid [(8R,15S)-diHETE] produced a dose-dependent hyperalgesia, as measured by decrease in threshold for paw withdrawal. The isomer (8S,15S)-diHETE antagonized in a dose-dependent manner this hyperalgesia due to (8R,15S)-diHETE but did not suppress prostaglandin E2-induced hyperalgesia. (8S,15S)-DiHETE produced a dose-dependent hypoalgesia, as reflected by an increase in nociceptive threshold, suggesting a contribution of endogenous (8R,15S)-diHETE to normal nociceptive threshold. The hypoalgesic effect of (8S,15S)-diHETE was blocked by corticosteroids but not by the cyclooxygenase inhibitor indomethacin. Neither (8R,15S)-dihydroxyeicosa-(5,15E-9,11Z)-tetraenoic acid nor (8R,15S)-dihydroxyeicosa-(5,11E-9,13Z)-tetraenoic acid exhibited any hyperalgesic or hypoalgesic activity. The stereospecificity of the effect of (8R,15S)-diHETE suggests that the induction of hyperalgesia is a receptor-dependent phenomenon and that (8S,15S)-diHETE may be an effective receptor-directed antagonist. The (8R,15S)-diHETE and (8S,15S)-diHETE from PMNL, keratinocytes, and other epithelial cells may modulate normal primary afferent function and contribute to inflammatory hyperalgesia. PMID:3014543

  13. Increased isoprostane levels in oleic acid-induced lung injury

    SciTech Connect

    Ono, Koichi; Koizumi, Tomonobu; Tsushima, Kenji; Yoshikawa, Sumiko; Yokoyama, Toshiki; Nakagawa, Rikimaru; Obata, Toru

    2009-10-16

    The present study was performed to examine a role of oxidative stress in oleic acid-induced lung injury model. Fifteen anesthetized sheep were ventilated and instrumented with a lung lymph fistula and vascular catheters for blood gas analysis and measurement of isoprostanes (8-epi prostaglandin F2{alpha}). Following stable baseline measurements, oleic acid (0.08 ml/kg) was administered and observed 4 h. Isoprostane was measured by gas chromatography mass spectrometry with the isotope dilution method. Isoprostane levels in plasma and lung lymph were significantly increased 2 h after oleic acid administration and then decreased at 4 h. The percent increases in isoprostane levels in plasma and lung lymph at 2 h were significantly correlated with deteriorated oxygenation at the same time point, respectively. These findings suggest that oxidative stress is involved in the pathogenesis of the pulmonary fat embolism-induced acute lung injury model in sheep and that the increase relates with the deteriorated oxygenation.

  14. γ-Hydroxybutyric Acid-Induced Electrographic Seizures

    PubMed Central

    Cheung, Joseph; Lucey, Brendan P.; Duntley, Stephen P.; Darken, Rachel S.

    2014-01-01

    We describe a case of absence-like electrographic seizures during NREM sleep in a patient who was taking sodium oxybate, a sodium salt of γ-hydroxybutyric acid (GHB). An overnight full montage electroencephalography (EEG) study revealed numerous frontally predominant rhythmic 1.5-2 Hz sharp waves and spike-wave activity during stage N2 and N3 sleep at the peak dose time for sodium oxybate, resembling atypical absence-like electrographic seizures. The patient was later weaned off sodium oxybate, and a repeat study did not show any such electrographic seizures. Absence-like seizures induced by GHB had previously been described in experimental animal models. We present the first reported human case of absence-like electrographic seizure associated with sodium oxybate. Citation: Cheung J, Lucey BP, Duntley SP, Darken RS. γ-hydroxybutyric acid-induced electrographic seizures. J Clin Sleep Med 2014;10(7):811-812. PMID:25024661

  15. [Sunitinib and zoledronic acid induced osteonecrosis of the jaw].

    PubMed

    Sos, Balzs; Vajta, Lszl; Szalma, Jzsef

    2015-11-15

    The tendency for bisphosphonate and non-bisphosphonate (eg.: antiresorptive or anti-angiogenesis drugs) induced osteonecrosis is increasing. Treatment of these patients is a challenge both for dentists and for oral and maxillofacial surgeons. Cooperation with the drug prescribing general medicine colleagues to prevent osteonecrosis is extremely important. Furthermore, prevention should include dental focus elimination, oral hygienic instructions and education, dental follow-up and, in case of manifest necrosis, referral to maxillofacial departments. Authors outline the difficulties of conservative and surgical treatment of a patient with sunitinib and zoledronic acid induced osteonecrosis. The patient became symptomless and the operated area healed entirely six and twelve months postoperatively. A long term success further follow-up is necessary to verify long-term success. PMID:26548471

  16. The Effect of Ear Canal Pressure on Spontaneous Otoacoustic Emissions:. Comparison Between Human and Lizard Ears

    NASA Astrophysics Data System (ADS)

    van Dijk, P.; Manley, G. A.

    2009-02-01

    The center frequency, height and width of peaks in SOAE spectra depend on ear canal pressure. The width is interpreted as a measure of the inner ear source-signal-to-(e.g. thermal)-noise ratio. In humans, width increases with decreasing height. Apparently, ear canal pressure modifies the amplitude of the inner ear emission source signal. In lizards, the relation between peak width and height is not consistent. Here, middle ear transmission changes may account for many the observed amplitude effects.

  17. Postoperative ramifications of total ear replantation.

    PubMed

    Finical, S J; Keller, K M; Lovett, J E

    1998-12-01

    Complete avulsion of the external ear, much less common than other minor ear trauma, presents a complex and difficult problem. The authors present a 35-year-old male cigarette smoker who suffered traumatic avulsion of the right ear, and describe the replantation procedure and the patient's postoperative course. Aesthetic positioning of the replanted ear, treating the external auditory meatus, protecting the ear against exposure to the sun, and counseling the patient about issues related to sensation are important factors in the care of patients who have undergone such a procedure. PMID:9869143

  18. [Gas ventilation through middle ear mucosa].

    PubMed

    Ohno, F; Imakiire, T; Nobori, T; Ohyama, M

    1993-11-01

    The possible effects of gas ventilation via the middle ear mucosa on middle ear pressure changes with N2O inhalation were studied. Sixty-seven ears without otologic problems were selected from among cases undergoing ENT surgery under general anesthesia. Anesthesia was induced by isoflurane or sevoflurane, and inhalation with a gas mixture of 21/min O2 and 31/min N2O was started under controlled respiration via endotracheal tube. Middle ear pressure was measured each minute with tympanometry just before and during N2O inhalation. Changes in pressure were plotted against time on an X-Y plotter, and the rate of middle ear pressure change and pressure change in 10 minutes were calculated. The following results were obtained; 1. In all cases, the middle ear pressure rose with N2O inhalation. However, the same concentration of N2O created different middle ear pressure changes in different individuals varying from 1.6 mmH2O to 107.8 mmH2O per minute. 2. The rate of middle ear pressure elevation tended to be greater in younger subjects, especially in children aged 4 to 7. 3. There was a negative correlation between the middle ear pressure change and pneumatization of the middle ear. 4. Sex, pulmonary function, and the N2O expiratory flow concentration did not contribute to the variability in the rate of the middle ear pressure elevation. PMID:8283337

  19. EEG Recorded from the Ear: Characterizing the Ear-EEG Method

    PubMed Central

    Mikkelsen, Kaare B.; Kappel, Simon L.; Mandic, Danilo P.; Kidmose, Preben

    2015-01-01

    Highlights Auditory middle and late latency responses can be recorded reliably from ear-EEG.For sources close to the ear, ear-EEG has the same signal-to-noise-ratio as scalp.Ear-EEG is an excellent match for power spectrum-based analysis. A method for measuring electroencephalograms (EEG) from the outer ear, so-called ear-EEG, has recently been proposed. The method could potentially enable robust recording of EEG in natural environments. The objective of this study was to substantiate the ear-EEG method by using a larger population of subjects and several paradigms. For rigor, we considered simultaneous scalp and ear-EEG recordings with common reference. More precisely, 32 conventional scalp electrodes and 12 ear electrodes allowed a thorough comparison between conventional and ear electrodes, testing several different placements of references. The paradigms probed auditory onset response, mismatch negativity, auditory steady-state response and alpha power attenuation. By comparing event related potential (ERP) waveforms from the mismatch response paradigm, the signal measured from the ear electrodes was found to reflect the same cortical activity as that from nearby scalp electrodes. It was also found that referencing the ear-EEG electrodes to another within-ear electrode affects the time-domain recorded waveform (relative to scalp recordings), but not the timing of individual components. It was furthermore found that auditory steady-state responses and alpha-band modulation were measured reliably with the ear-EEG modality. Finally, our findings showed that the auditory mismatch response was difficult to monitor with the ear-EEG. We conclude that ear-EEG yields similar performance as conventional EEG for spectrogram-based analysis, similar timing of ERP components, and equal signal strength for sources close to the ear. Ear-EEG can reliably measure activity from regions of the cortex which are located close to the ears, especially in paradigms employing frequency-domain analyses. PMID:26635514

  20. The War of Jenkins Ear

    PubMed Central

    Graboyes, Evan M.; Hullar, Timothy E.

    2012-01-01

    Objective In 1731, Spanish sailors boarded the British brig Rebecca off the coast of Cuba and sliced off the left ear of its captain, Robert Jenkins. This traumatic auriculectomy was used as a pretext by the British to declare war on Spain in 1739, a conflict that is now known as the War of Jenkins Ear. Here, we examine the techniques available for auricular repair at the time of Jenkins injury and relate them to the historical events surrounding the incident. Methods Review of relevant original published manuscripts and monographs. Results Surgeons in the mid-18th century did not have experience with repair of traumatic total auriculectomies. Some contemporary surgeons favored auricular prostheses over surgical treatment. Methods for the reconstruction of partial defects were available, and most authors advocated a local post-auricular flap instead of a free tissue transfer. Techniques for repair of defects of the auricle lagged behind those for repair of the nose. Conclusion Limitations in care of traumatic auricular defects may have intensified the significance of Jenkins injury and helped lead to the War of Jenkins Ear, but conflict between Britain and Spain was probably unavoidable due to their conflicting commercial interests in the Caribbean. PMID:23444484

  1. Ear canal dynamic motion as a source of power for in-ear devices

    NASA Astrophysics Data System (ADS)

    Delnavaz, Aidin; Voix, Jrmie

    2013-02-01

    Ear canal deformation caused by temporomandibular joint (jaw joint) activity, also known as "ear canal dynamic motion," is introduced in this paper as a candidate source of power to possibly recharge hearing aid batteries. The geometrical deformation of the ear canal is quantified in 3D by laser scanning of different custom ear moulds. An experimental setup is proposed to measure the amount of power potentially available from this source. The results show that 9 mW of power is available from a 15 mm3 dynamic change in the ear canal volume. Finally, the dynamic motion and power capability of the ear canal are investigated in a group of 12 subjects.

  2. Regulation of vascular prostaglandin synthesis by metabolites of arachidonic acid in perfused rabbit aorta.

    PubMed Central

    Kent, R S; Diedrich, S L; Whorton, A R

    1983-01-01

    To address the hypothesis that metabolites of arachidonic acid are important regulators of prostaglandin (PG) synthesis in intact vascular tissue, we studied arachidonate metabolism in rabbit aortas in response to a continuous infusion of arachidonic acid, 10 micrograms/ml. Prostacyclin (PGI2; measured as 6-keto-PGF1 alpha) production rate accelerated during the first 2 min, reached peak velocity at 2 min, and then progressively decelerated. The velocity profile of PGI2 production was similar to that previously reported for cyclooxygenase holoenzyme assayed in vitro, and was consistent with progressive inactivation of the enzymes leading to PGI2 synthesis. We determined the specific inhibition of cyclooxygenase and prostacyclin synthetase by measuring PGI2 and PGE2 production rates and by infusing cyclic endoperoxides. Our results indicate preferential inactivation of cyclooxygenase during arachidonate metabolism, most likely due to cyclooxygenase-derived oxidative intermediates. This was a dose-dependent response and resulted in a progressive decrease in the 6-keto-PGF1 alpha/PGE2 ratio. Exogenously added 15-hydroperoxy eicosatetraenoic acid, on the other hand, actually stimulated cyclooxygenase activity at low doses, while markedly inhibiting prostacyclin synthetase. This finding, along with the accelerating nature of arachidonate metabolism, is consistent with the concept of "peroxide tone" as a mediator of cyclooxygenase activity in this system. These results demonstrate that arachidonate metabolites regulate PG synthesis in intact blood vessels. The progressive enzymatic inhibition intrinsic to arachidonate metabolism may be a model for similar changes occurring in states of enhanced lipid peroxidation. These metabolic alterations might greatly influence the numerous vascular functions known to involve arachidonic acid metabolism. PMID:6409932

  3. Arachidonic acid metabolism in fibroblasts derived from canine myocardium

    SciTech Connect

    Weber, D.R.; Prescott, S.M.

    1986-03-05

    Canine fibroblasts from normal or healing infarcted myocardium were grown in culture. The cells were morphologically indistinguishable, but the doubling time of cells from healing myocardium was 39.6 +/- 3.5 hr whereas that of normals was 24 +/- 3.7 (n=5, p < .025). Fibroblasts incorporated (/sup 3/H)arachidonate (AA) into phospholipids. Calcium ionophore A23187 (10 ..mu..M) caused release and metabolism of (/sup 3/H) AA. A23187 or AA (10..mu..M) induced production of 6-keto PGF1..cap alpha.., PGE2, and a hydroxy metabolite of AA. RIA of 6-keto PGF1..cap alpha.. showed that subconfluent cells from healing myocardium produced 1202 +/- 354 pg/mg protein whereas that of normals was 551 +/- 222 (n=7, p < .025). Histamine and bradykinin also induced AA metabolism but were less potent. They examined the effect of AA released from deteriorating myocytes on AA metabolism by cultured fibroblasts. They confirmed that isolated myocytes labelled with (/sup 3/H)AA released but did not metabolize (/sup 3/H)AA. In coincubations, fibroblasts incorporated myocyte-derived AA. Subsequent stimulation of the fibroblasts with A23187 induced the synthesis of 6-keto PGF1..cap alpha.., PGE2 and a hydroxy metabolite. The fibroblast content of healing myocardium was 35-1000 times that of normal tissue (n=7). Thus even a moderate change in AA metabolism, amplified by the AA released from deteriorating myocytes, may be a significant physiologic or pathologic event.

  4. Ancestral genetic complexity of arachidonic acid metabolism in Metazoa.

    PubMed

    Yuan, Dongjuan; Zou, Qiuqiong; Yu, Ting; Song, Cuikai; Huang, Shengfeng; Chen, Shangwu; Ren, Zhenghua; Xu, Anlong

    2014-09-01

    Eicosanoids play an important role in inducing complex and crucial physiological processes in animals. Eicosanoid biosynthesis in animals is widely reported; however, eicosanoid production in invertebrate tissue is remarkably different to vertebrates and in certain respects remains elusive. We, for the first time, compared the orthologs involved in arachidonic acid (AA) metabolism in 14 species of invertebrates and 3 species of vertebrates. Based on parsimony, a complex AA-metabolic system may have existed in the common ancestor of the Metazoa, and then expanded and diversified through invertebrate lineages. A primary vertebrate-like AA-metabolic system via cyclooxygenase (COX), lipoxygenase (LOX), and cytochrome P450 (CYP) pathways was further identified in the basal chordate, amphioxus. The expression profiling of AA-metabolic enzymes and lipidomic analysis of eicosanoid production in the tissues of amphioxus supported our supposition. Thus, we proposed that the ancestral complexity of AA-metabolic network diversified with the different lineages of invertebrates, adapting with the diversity of body plans and ecological opportunity, and arriving at the vertebrate-like pattern in the basal chordate, amphioxus. PMID:24801744

  5. Dietary arachidonic acid in perinatal nutrition: a commentary.

    PubMed

    Lauritzen, Lotte; Fewtrell, Mary; Agostoni, Carlo

    2015-01-01

    Arachidonic acid (AA) is supplied together with docosahexaenoic acid (DHA) in infant formulas, but we have limited knowledge about the effects of supplementation with either of these long-chain polyunsaturated fatty acids (LCPUFA) on growth and developmental outcomes. AA is present in similar levels in breast milk throughout the world, whereas the level of DHA is highly diet dependent. Autopsy studies show similar diet-dependent variation in brain DHA, whereas AA is little affected by intake. Early intake of DHA has been shown to affect visual development, but the effect of LCPUFA on neurodevelopment remains to be established. Few studies have found any functional difference between infants supplemented with DHA alone compared to DHA+AA, but some studies show neurodevelopmental advantages in breast-fed infants of mothers supplemented with n-3 LCPUFA alone. It also remains to be established whether the AA/DHA balance could affect allergic and inflammatory outcomes later in life. Disentangling effects of genetic variability and dietary intake on AA and DHA-status and on functional outcomes may be an important step in the process of determining whether AA-intake is of any physiological or clinical importance. However, based on the current evidence we hypothesize that dietary AA plays a minor role on growth and development relative to the impact of dietary DHA. PMID:25314584

  6. Arachidonate 12-lipoxygenases with reference to their selective inhibitors

    SciTech Connect

    Yamamoto, Shozo . E-mail: yamamosh@kyoto-wu.ac.jp; Katsukawa, Michiko; Nakano, Ayumi; Hiraki, Emi; Nishimura, Kohji; Jisaka, Mitsuo; Yokota, Kazushige; Ueda, Natsuo

    2005-12-09

    Lipoxygenase is a dioxygenase recognizing a 1-cis,4-cis-pentadiene of polyunsaturated fatty acids. The enzyme oxygenates various carbon atoms of arachidonic acid as a substrate and produces 5-, 8-, 12- or 15-hydroperoxy eicosatetraenoic acid with a conjugated diene chromophore. The enzyme is referred to as 5-, 8-, 12- or 15-lipoxygenase, respectively. Earlier we found two isoforms of 12-lipoxygenase, leukocyte- and platelet-type enzymes, which were distinguished by substrate specificity, catalytic activity, primary structure, gene intron size, and antigenicity. Recently, the epidermis-type enzyme was found as the third isoform. Attempts have been made to find isozyme-specific inhibitors of 12-lipoxygenase, and earlier we found hinokitol, a tropolone, as a potent inhibitor selective for the platelet-type 12-lipoxygenase. More recently, we tested various catechins of tea leaves and found that (-)-geotechnical gallate was a potent and selective inhibitor of human platelet 12-lipoxygenase with an IC{sub 5} of 0.14 {mu}M. The compound was much less active with 12-lipoxygenase of leukocyte-type, 15-, 8-, and 5-lipoxygenases, and cyclo oxygenases-1 and -2.

  7. The rabbit pulmonary cytochrome P450 arachidonic acid metabolic pathway: characterization and significance.

    PubMed Central

    Zeldin, D C; Plitman, J D; Kobayashi, J; Miller, R F; Snapper, J R; Falck, J R; Szarek, J L; Philpot, R M; Capdevila, J H

    1995-01-01

    Cytochrome P450 metabolizes arachidonic acid to several unique and biologically active compounds in rabbit liver and kidney. Microsomal fractions prepared from rabbit lung homogenates metabolized arachidonic acid through cytochrome P450 pathways, yielding cis-epoxyeicosatrienoic acids (EETs) and their hydration products, vic-dihydroxyeicosatrienoic acids, mid-chain cis-trans conjugated dienols, and 19- and 20-hydroxyeicosatetraenoic acids. Inhibition studies using polyclonal antibodies prepared against purified CYP2B4 demonstrated 100% inhibition of arachidonic acid epoxide formation. Purified CYP2B4, reconstituted in the presence of NADPH-cytochrome P450 reductase and cytochrome b5, metabolized arachidonic acid, producing primarily EETs. EETs were detected in lung homogenate using gas chromatography/mass spectroscopy, providing evidence for the in vivo pulmonary cytochrome P450 epoxidation of arachidonic acid. Chiral analysis of these lung EETs demonstrated a preference for the 14(R),15(S)-, 11(S),12(R)-, and 8(S),9(R)-EET enantiomers. Both EETs and vic-dihydroxyeicosatrienoic acids were detected in bronchoalveolar lavage fluid. At micromolar concentrations, methylated 5,6-EET and 8,9-EET significantly relaxed histamine-contracted guinea pig hilar bronchi in vitro. In contrast, 20-hydroxyeicosatetraenoic acid caused contraction to near maximal tension. We conclude that CYP2B4, an abundant rabbit lung cytochrome P450 enzyme, is the primary constitutive pulmonary arachidonic acid epoxygenase and that these locally produced, biologically active eicosanoids may be involved in maintaining homeostasis within the lung. Images PMID:7738183

  8. Ionophore and Arachidonic Acid Stimulation of Airway Responses in Rhesus Monkeys

    PubMed Central

    Patterson, Roy; Harris, Kathleen E.; Greenberger, Paul A.

    1979-01-01

    Aerosolized doses of the ionophore, A23187, and arachidonic acid individually resulted in no airway response in rhesus monkeys. When these two agents were given simultaneously, by aerosol, an airway response occurred. The pulmonary function abnormalities that occurred qualitatively simulated those of an antigen-induced airway response. This is the first demonstration in our laboratory of two agents which singly will not produce a response but which are reactive when delivered in combination. Other fatty acids did not produce a similar response. The response to A23187 and arachidonic acid occurred only in rhesus monkeys from our colony which had been demonstrated to have airway responses to aerosolized antigen challenge, a response shown previously to be associated with hyperreactive airways to pharmacologic stimuli. The A23187 and arachidonic acid response was inhibited by aerosolized 5,8,11,14-eicosatetraynoic acid, an inhibitor of the cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism. Further, indomethacin, a prostaglandin synthetase inhibitor of the cyclooxygenase pathway, inhibited the response, although previous studies showed that this drug will potentiate an antigen-induced response in this animal model of asthma. The slow-reacting substance of anaphylaxis antagonist, FPL 55712, did not inhibit the A23187-arachidonic acid response under the conditions of these experiments. The mechanism of the A23187-arachidonic acid airway response in rhesus monkeys may or may not be the same as the antigen-induced response. PMID:109472

  9. In vitro release of arachidonic acid and in vivo responses to respirable fractions of cotton dust

    SciTech Connect

    Thomson, T.A.; Edwards, J.H.; Al-Zubaidy, T.S.; Brown, R.C.; Poole, A.; Nicholls, P.J.

    1986-04-01

    It was considered that the fall in lung function seen after exposure to cotton dust may be attributable in part to the activity of arachidonic acid metabolites, such as leucotrienes as well as to the more established release of histamine by cotton dust. However, we found that cotton and barley dusts elicited poor release of arachidonic acid from an established macrophage like cell line compared with that observed with other organic dusts. In the experimental animal, pulmonary cellular responses to both cotton and barley dust were similar to those evoked by moldy hay and pigeon dropping dusts, although after multiple doses a more severe response was seen to cotton and barley. Since both moldy hay and pigeon droppings elicit a greater arachidonic acid release than cotton or barley, a role for arachidonic acid in inducing the cellular response is less likely than other factors. There are limitations to our conclusions using this system, i.e., the arachidonic acid may be released in a nonmetabolized form, although it is noted that the two dusts with the greatest arachidonic acid release produce their clinical responses in humans largely by hypersensitivity mechanisms.

  10. Activation and regulation of arachidonic acid release in rabbit peritoneal neutrophils

    SciTech Connect

    Tao, W.

    1988-01-01

    Arachidonic acid release in rabbit neutrophils can be enhanced by the addition of chemotactic fMet-Leu-Phe, platelet-activating factor, PAF, or the calcium ionophore A23187. Over 80% of the release ({sup 3}H)arachidonic acid comes from phosphatidylcholine and phosphatidylinositol. The release is dose-dependent and increases with increasing concentration of the stimulus. The A23187-induced release increases with increasing time of the stimulation. ({sup 3}H)arachidonic acid release, but not the rise in the concentration of intracellular calcium, is inhibited in pertussis toxin-treated neutrophils stimulated with PAF. The ({sup 3}H)arachidonic acid released by A23187 is potentiated while that release by fMET-Leu-Phe or PAF is inhibited in phorbol 12-myristate 13-acetate, PMA, treated rabbit neutrophils. The protein kinase C inhibitor 1-(5-isoquinoline sulfonyl)-2-methylpiperazine, H-7, has no effect on the potentiation by PMA of the A23187-induced release, it prevents the inhibition by PMA of the release produced by PAF or fMet-Leu-Phe. In addition, PMA increases arachidonic acid release in H-7-treated cells stimulated with fMet-Leu-Phe. The diacylglycerol kinase inhibitor R59022 increases the level of diacylglycerol in neutrophils stimulated with fMet-Leu-Phe. Furthermore, R59022 potentiates ({sup 3}H) arachidonic acid release produced by fMet-Leu-Phe. This potentiation is not inhibited by H-7, in fact, it is increased in H-7-treated neutrophils.

  11. Arachidonic acid stimulates /sup 45/calcium efflux and HPL release in isolated trophoblast cells

    SciTech Connect

    Zeitler, P.; Murphy, E.; Handwerger, S.

    1986-01-13

    Previous investigations from this laboratory have indicated that arachidonic acid stimulates a rapid, dose-dependent and reversible increase in hPL release which is not dependent on cyclooxygenase or lipoxygenase metabolism. To investigate further the mechanism by which arachidonic acid stimulates the release of hPL, the effect of arachidonic acid on the release of /sup 45/Ca from perifused cells prelabelled with /sup 45/Ca was examined in an enriched cell culture population of term human syncytiotrophoblast. Arachidonic acid (10-100 ..mu..M) stimulated a dose-dependent, rapid, and reversible increase in the release of both /sup 45/Ca and hPL from the perifused placental cells. On the other hand, palmitic acid had little effect on either hPL release or /sup 45/Ca release even at concentrations as high as 100 ..mu..M. Ionophore A23187 (1-10..mu..M) also stimulated a dose-dependent and reversible increase in hPL release. Since arachidonic acid increases the mobilization of cellular calcium, as reflected by the increased /sup 45/calcium efflux, and since an increase in the intracellular calcium concentration appears to stimulate an increase in hPL release, these results suggest that the stimulation of hPL release by arachidonic acid may be due, at least in part, to the effects of the fatty acid on cellular calcium mobilization. 26 references, 5 figures.

  12. Sphingoid bases inhibit acid-induced demineralization of hydroxyapatite.

    PubMed

    Valentijn-Benz, Marianne; van 't Hof, Wim; Bikker, Floris J; Nazmi, Kamran; Brand, Henk S; Sotres, Javier; Lindh, Liselott; Arnebrant, Thomas; Veerman, Enno C I

    2015-01-01

    Calcium hydroxyapatite (HAp), the main constituent of dental enamel, is inherently susceptible to the etching and dissolving action of acids, resulting in tooth decay such as dental caries and dental erosion. Since the prevalence of erosive wear is gradually increasing, there is urgent need for agents that protect the enamel against erosive attacks. In the present study we studied in vitro the anti-erosive effects of a number of sphingolipids and sphingoid bases, which form the backbone of sphingolipids. Pretreatment of HAp discs with sphingosine, phytosphingosine (PHS), PHS phosphate and sphinganine significantly protected these against acid-induced demineralization by 80 17%, 78 17%, 78 7% and 81 8%, respectively (p < 0.001). On the other hand, sphingomyelin, acetyl PHS, octanoyl PHS and stearoyl PHS had no anti-erosive effects. Atomic force measurement revealed that HAp discs treated with PHS were almost completely and homogeneously covered by patches of PHS. This suggests that PHS and other sphingoid bases form layers on the surface of HAp, which act as diffusion barriers against H(+) ions. In principle, these anti-erosive properties make PHS and related sphingosines promising and attractive candidates as ingredients in oral care products. PMID:25300299

  13. Computerized image analysis for acetic acid induced intraepithelial lesions

    NASA Astrophysics Data System (ADS)

    Li, Wenjing; Ferris, Daron G.; Lieberman, Rich W.

    2008-03-01

    Cervical Intraepithelial Neoplasia (CIN) exhibits certain morphologic features that can be identified during a visual inspection exam. Immature and dysphasic cervical squamous epithelium turns white after application of acetic acid during the exam. The whitening process occurs visually over several minutes and subjectively discriminates between dysphasic and normal tissue. Digital imaging technologies allow us to assist the physician analyzing the acetic acid induced lesions (acetowhite region) in a fully automatic way. This paper reports a study designed to measure multiple parameters of the acetowhitening process from two images captured with a digital colposcope. One image is captured before the acetic acid application, and the other is captured after the acetic acid application. The spatial change of the acetowhitening is extracted using color and texture information in the post acetic acid image; the temporal change is extracted from the intensity and color changes between the post acetic acid and pre acetic acid images with an automatic alignment. The imaging and data analysis system has been evaluated with a total of 99 human subjects and demonstrate its potential to screening underserved women where access to skilled colposcopists is limited.

  14. Unsaturated fatty acids induce non-canonical autophagy.

    PubMed

    Niso-Santano, Mireia; Malik, Shoaib Ahmad; Pietrocola, Federico; Bravo-San Pedro, Jos Manuel; Mario, Guillermo; Cianfanelli, Valentina; Ben-Youns, Amena; Troncoso, Rodrigo; Markaki, Maria; Sica, Valentina; Izzo, Valentina; Chaba, Kariman; Bauvy, Chantal; Dupont, Nicolas; Kepp, Oliver; Rockenfeller, Patrick; Wolinski, Heimo; Madeo, Frank; Lavandero, Sergio; Codogno, Patrice; Harper, Francis; Pierron, Grard; Tavernarakis, Nektarios; Cecconi, Francesco; Maiuri, Maria Chiara; Galluzzi, Lorenzo; Kroemer, Guido

    2015-04-15

    To obtain mechanistic insights into the cross talk between lipolysis and autophagy, two key metabolic responses to starvation, we screened the autophagy-inducing potential of a panel of fatty acids in human cancer cells. Both saturated and unsaturated fatty acids such as palmitate and oleate, respectively, triggered autophagy, but the underlying molecular mechanisms differed. Oleate, but not palmitate, stimulated an autophagic response that required an intact Golgi apparatus. Conversely, autophagy triggered by palmitate, but not oleate, required AMPK, PKR and JNK1 and involved the activation of the BECN1/PIK3C3 lipid kinase complex. Accordingly, the downregulation of BECN1 and PIK3C3 abolished palmitate-induced, but not oleate-induced, autophagy in human cancer cells. Moreover, Becn1(+/-) mice as well as yeast cells and nematodes lacking the ortholog of human BECN1 mounted an autophagic response to oleate, but not palmitate. Thus, unsaturated fatty acids induce a non-canonical, phylogenetically conserved, autophagic response that in mammalian cells relies on the Golgi apparatus. PMID:25586377

  15. Numerical simulation of the human ear and the dynamic analysis of the middle ear sound transmission

    NASA Astrophysics Data System (ADS)

    Yao, W.; Ma, J.; Huang, X.

    2013-06-01

    Based on the clinical CT of normal right ear, a 3-D ?nite element (FE) model of the human ear consisting of the external ear canal, middle ear(tympanic membrane, ossicular chain, ligaments, tendons), and inner ear (including semicircular canals, vestibular, spiral cochlear)was constructed in this paper. The complicated structures and inner boundary conditions of middle ear were described in this model. Model analysis and acoustic-structure-?uid coupled dynamic frequency response analysis were conducted on the model. The validity of this model was confirmed by comparing the results with published experimental data. The amplitudes and velocities of tympanic membrane and stapes footplate, sound pressure gain across the middle ear, and the cochlear input impedance were derived. Besides, it was concluded that the ear canal can amplify the sound signal in low frequencies.The modes of vibration of middle ear auditory ossicles, oval window and round window have been analysed. This model can well simulate the acoustic behavior with the interaction of external ear, middle ear and inner ear, which can supply more valuable theoretical support for development and improvement of hearing-aid and artificial inner ear.

  16. Prominent ears: Anthropometric study of the external ear of primary school children of Harare, Zimbabwe

    PubMed Central

    Muteweye, Wilfred; Muguti, Godfrey I.

    2015-01-01

    Background Prominent ear is the most common congenital ear deformity affecting 5% of children in the Western world and has profound psychosocial effects on the bearer. It is important to know the prevalence in the local population to have a better appreciation of the local burden of the abnormality as well as to know the parameters of ear morphology locally. These parameters can be useful in the diagnosis and evaluation of ear anomalies and may help reconstructive surgeons in reproducing an anatomically correct ear of an African/Zimbabwean child. Objectives To evaluate the frequency of prominent ears in black school going children in Zimbabwe and to establish morphometric properties of the ear. Design Prospective observational, cross sectional study. Setting Three Primary schools in Harare. Two in a high density area and one in a low density area. Materials and methods Three Primary schools in Harare were selected at random. The following measurements were taken: ear lengths, ear projection and face height using a sliding caliper. Three hundred and five healthy pupils of the age range 9–13 years of both sexes were included in the study, whilst children with congenital anomalies, ear tumours and history of ear trauma were excluded. Results The mean ear height across the cohort was 56.95 ± 5.00 (right ear) and 56.86 ± 4.92 (left ear). Ear projection was 19.52 ± 2.14 (right ear) and 19.59 ± 2.09 (left ear). Gender related differences were noted. Mean ear height was significantly higher in males (p-value = 0.000). Ear projection was higher in males compared to females. A total of 6.89% had prominent ears. Among males, 7.69% had prominent ears whilst 6.17% of females had prominent ears. Conclusion The prevalence of prominent ear among black African children in the studied population is comparable to that of Caucasians. The study provides a set of biometric data of auricular dimensions for normal black African children aged 9–13 years. PMID:26468372

  17. Bacteriology of the chronically discharging middle ear.

    PubMed

    Karma, P; Jokippi, L; Ojala, K; Jokipii, A M

    1978-01-01

    Suitable bacteriological techniques revealed anaerobic bacteria in 38 (33%) of 114 chronically discharging middle ears. The genus Bacteroides was cultured from 25 ears. Aerobic bacteriology showed the predominance of staphylococci, facultative enteric gramnegative rods, diphtheroid bacilli and Pseudomonas species. Anaerobic bacterial cultures were always mixed with aerobic bacteria. 12 ears were culture-negative, and 9 of the 108 Gram-stained smers revealed no bacteria. No significant difference in bacteriology was noted between ears with or without local antimicrobial treatment, or between profusely draining or only moist ears. The ears with postoperative recurrent infection or with clinical suspicion of cholesteatoma grew anaerobes significantly more often, and were seldom sterile. Because anaerobic bacteria are frequently associated with chronic otitis media, their characteristics with regard to susceptibility to antimicrobials and to air must be remembered in the choice of therapy. PMID:358732

  18. Local Inner Ear Drug Delivery and Pharmacokinetics

    PubMed Central

    Salt, Alec N.; Plontke, Stefan K.R.

    2008-01-01

    Summary A number of drugs are in widespread clinical use for the treatment of inner ear disorders by applying them directly to the inner ear. Many new substances and drug delivery systems specific to the inner ear are under development, and in some cases are undergoing evaluations in animal experiments and in clinical studies. The pharmacokinetics of drugs in the inner ear, however, is not well defined and the field is plagued by technical problems in obtaining pure samples of the inner ear fluids for analysis. Nevertheless, a basic understanding of the mechanisms of drug dispersal in the inner ear has emerged that facilitates the design and interpretation of future pharmacokinetic studies. PMID:16214674

  19. Listening to Nature's orchestra with peculiar ears

    NASA Astrophysics Data System (ADS)

    Yager, David D.

    2003-04-01

    Insects use hearing for the crucial tasks of communicating with conspecifics and avoiding predators. Although all are based on the same acoustic principles, the diversity of insect ears is staggering and instructive. For instance, a South African grasshopper demonstrates that hearing conspecific calls is possible over distances 1 km with ears that do not have tympana. Actually, these creatures have six pairs of ears that play different roles in behavior. In numerical contrast, praying mantises have just a single ear in the ventral midline. The ear is very effective at detecting ultrasonic bat cries. However, the bioacoustics of sound transduction by two tympana facing each other in a deep, narrow slit is a puzzle. Tachinid flies demonstrate that directional hearing at 5 kHz is possible with a pair of ears fused together to give a total size of 1 mm. The ears are under the fly's chin. Hawk moths have their ears built into their mouthparts and the tympanum is more like a hollow ball than the usual membrane. As an apt last example, cicada ears are actually part of the orchestra: their tympana function both in sound reception and sound production.

  20. Milestones in the History of Ear Reconstruction.

    PubMed

    Berghaus, Alexander; Nicol, Marion San

    2015-12-01

    The reconstruction of ear deformities has been challenging plastic surgeons since centuries. However, it is only in the 19th century that reports on partial and total ear reconstruction start increasing. In the quest for an aesthetically pleasing and natural-looking result, surgeons worked on the perfect framework and skin coverage. Different materials and flap techniques have evolved. Some were abandoned out of frustration, while others kept evolving over the years. In this article, we discuss the milestones in ear reconstruction-from ancient times to early attempts in Western civilization to the key chapters of ear reconstruction in the 20th century leading to the current techniques. PMID:26667630

  1. An Effective 3D Ear Acquisition System

    PubMed Central

    Liu, Yahui; Lu, Guangming; Zhang, David

    2015-01-01

    The human ear is a new feature in biometrics that has several merits over the more common face, fingerprint and iris biometrics. It can be easily captured from a distance without a fully cooperative subject. Also, the ear has a relatively stable structure that does not change much with the age and facial expressions. In this paper, we present a novel method of 3D ear acquisition system by using triangulation imaging principle, and the experiment results show that this design is efficient and can be used for ear recognition. PMID:26061553

  2. Management of Chronic Middle Ear Effusion

    PubMed Central

    Thomas, Gary L.

    1969-01-01

    Management of chronic middle ear effusion must center around the reestablishment of normal eustachian tube function. If fluid does not clear with medical management, aspiration becomes necessary. A prosthetic eustachian tube is placed in the tympanic membrane in order to artificially ventilate the middle ear space while primary etiologic factors are being corrected. Unless recurrent or chronic ear disease of this nature is diligently treated, progressive damage may bring about irreversible hearing loss and the potentially dangerous disease, cholesteatoma of the ear. ImagesFigure 1.Figure 2. PMID:5798499

  3. Heart arachidonic acid is uniquely sensitive to dietary arachidonic acid and docosahexaenoic acid content in domestic piglets

    PubMed Central

    Tyburczy, Cynthia; Kothapalli, Kumar S. D.; Park, Woo Jung; Blank, Bryant S.; Bradford, Kathryn Lee; Zimmer, J. Paul; Butt, Christopher M.; Salem, Norman; Brenna, J. Thomas

    2011-01-01

    This study determined the sensitivity of heart and brain arachidonic acid (ARA) and docosahexaenoic acid (DHA) to the dietary ARA level in a dose-response design with constant, high DHA in neonatal piglets. On day 3 of age, pigs were assigned to 1 of 6 dietary formulas varying in ARA/DHA as follows (% fatty acid, FA/FA): (A1) 0.1/1.0; (A2) 0.53/1.0; (A3-D3) 0.69/1.0; (A4) 1.1/1.0; (D2) 0.67/0.62; (D1) 0.66/0.33. At necropsy (day 28) higher levels of dietary ARA were associated with increased heart and liver ARA, while brain ARA remained unaffected. Dietary ARA had no effect on tissue DHA accretion. Heart was particularly sensitive, with pigs in the intermediate groups having different ARA (A2, 18.6 0.7%; A3, 19.4 1.0%) and a 0.17% increase in dietary ARA resulted in a 0.84% increase in heart ARA. Further investigations are warranted to determine the clinical significance of heart ARA status in developing neonates. PMID:21885269

  4. Photodynamic drug action on isolated rat pancreatic acini. Mobilization of arachidonic acid and prostaglandin production.

    PubMed

    al-Laith, M; Matthews, E K; Cui, Z J

    1993-08-17

    Chloro-aluminium phthalocyanine sulphonate (SALPC) when photon-activated generates singlet oxygen, elicits amylase release and causes plasma membrane permeabilization of pancreatic acinar cells (Matthews and Cui, Biochem Pharmacol 39: 1444-1457, 1990). Amylase release precedes membrane permeabilization suggesting that the initial release of amylase may be due to direct stimulation by singlet oxygen of secretagogue receptors or their coupled guanine nucleotide binding proteins (G-proteins) and effector systems including phospholipase A2 (PLA2). The aim of the experiments reported here was to establish the extent to which PLA2 activation, arachidonic acid mobilization, and prostaglandin production are involved in the photon-induced action of SALPC on dispersed, perifused acini isolated from the rat pancreas. The mobilization of arachidonic acid by a major secretory stimulant of pancreatic exocrine cells, cholecystokinin octapeptide, was also assessed: it produced a time- and concentration-dependent (10(-10)-10(-6) M) stimulation of arachidonic acid output from acini prelabelled with [1-14C]arachidonic acid. In contrast, the kinetics of arachidonic acid mobilization with photon-activated SALPC 1 microM, 4500 or 18,400 lux light intensity (lambda > 570 mm), was biphasic, an intensity-dependent stimulation being preceded by a more immediate initial inhibition of output. Light activation of SALPC and singlet oxygen generation may evoke the stimulatory phase of arachidonic acid release by an action on G-proteins, or by PLA2 activated directly, or via calcium influx, because NaF 20 mM, mellitin 2 mg/mL and the calcium ionophore A23187 1 microM caused a 2.9-, 33- and 5-fold increase, respectively, in arachidonic acid output. However, not only was the arachidonate stimulation delayed in response to SALPC but in other experiments designed to gain more insight into the turnover of arachidonic acid and its metabolites, the photodynamic release of amylase preceded maximum prostaglandin E2 (PGE2) output and amylase release was completely unaffected when PGE2 production was blocked by the cyclo-oxygenase inhibitor, indomethacin 10 microM. It is therefore likely that the rapid initial photodynamic release of amylase from pancreatic acini induced by SALPC is mediated by activation of the signal transduction pathway involving the release of intracellular calcium; arachidonic acid mobilization and prostanoid production may then be linked to the longer-term, cytolytic action of SALPC, especially in tumour cells. PMID:7689843

  5. Acid-induced unfolding mechanism of recombinant human endostatin.

    PubMed

    Li, Bing; Wu, Xiaoyu; Zhou, Hao; Chen, Qianjie; Luo, Yongzhang

    2004-03-01

    Endostatin is a potent angiogenesis inhibitor. The structure of endostatin is unique in that its secondary structure is mainly irregular loops and beta-sheets and contains only a small fraction of alpha-helices with two pairs of disulfide bonds in a nested pattern. We choose human endostatin as a model system to study the folding mechanism of this kind. Nuclear magnetic resonance (NMR), tryptophan emission fluorescence, and circular dichroism (CD) were used to monitor the unfolding process of endostatin upon acid titration. Urea-induced unfolding was used to measure the stability of endostatin under different conditions. Our results show that endostatin is very acid-resistant; some native structure still remains even at pH 2 as evidenced by (1)H NMR. Trifluoroethanol (TFE) destabilizes native endostatin, while it makes endostatin even more acid-resistant in the low pH region. Stability measurement of endostatin suggests that endostatin is still in native structure at pH 3.5 despite the decreased stability. Acid-induced unfolding of endostatin is reversible, although it requires a long time to reach equilibrium below pH 3. Surprisingly, the alpha-helical content of endostatin is increased when it is unfolded at pH 1.6, and the alpha-helical content of the polypeptide chain of unfolded endostatin increases linearly with TFE concentration in the range of 0-30%. This observation indicates that the polypeptide chain of unfolded endostatin has an intrinsic alpha-helical propensity. Our discoveries may provide clues for refolding endostatin more efficiently. The acid-resistance property of endostatin may have biological significance in that it cannot be easily digested by proteases in an acidic environment such as in a lysosome in the cell. PMID:14992592

  6. Costs and benefits of jasmonic acid induced responses in soybean.

    PubMed

    Accamando, A K; Cronin, J T

    2012-06-01

    In response to herbivory, plants have evolved defense strategies to reduce herbivore preference and performance. A strategy whereby defenses are induced only upon herbivory can mitigate costs of defense when herbivores are scarce. Although costs and benefits of induced responses are generally assumed, empirical evidence for many species is lacking. Soybean (Glycine max L. Merr.) has emerged as a model species with which to address questions about induced responses. To our knowledge, this is the first study to examine the fitness costs and benefits of jasmonic acid-induced responses by soybean in the absence and presence of soybean loopers (Chrysodeix includens Walker) (Lepidoptera: Noctuidae). In a greenhouse experiment we demonstrated that soybean induction was costly. Induced plants produced 10.1% fewer seeds that were 9.0% lighter, and had 19.2% lower germination rates than noninduced plants. However, induction provided only modest benefits to soybeans. In a choice experiment, soybean loopers significantly preferred leaves from noninduced plants, consuming 62% more tissue than from induced plants. Soybean loopers that fed on plants that were previously subjected to treatment with jasmonic acid matured at the same rate and to the same size as those that fed on control plants. However, at high conspecific density, soybean looper survivorship was reduced by 44% on previously induced relative to control plants. Reduced soybean looper preference and survivorship did not translate into fitness benefits for soybeans. Our findings support theoretical predictions of costly induced defenses and highlight the importance of considering the environmental context in studies of plant defense. PMID:22732613

  7. Role of Arachidonic Acid in Promoting Hair Growth

    PubMed Central

    Munkhbayar, Semchin; Jang, Sunhyae; Cho, A-Ri; Choi, Soon-Jin; Shin, Chang Yup; Eun, Hee Chul; Kim, Kyu Han

    2016-01-01

    Background Arachidonic acid (AA) is an omega-6 polyunsaturated fatty acid present in all mammalian cell membranes, and involved in the regulation of many cellular processes, including cell survival, angiogenesis, and mitogenesis. The dermal papilla, composed of specialized fibroblasts located in the bulb of the hair follicle, contributes to the control of hair growth and the hair cycle. Objective This study investigated the effect of AA on hair growth by using in vivo and in vitro models. Methods The effect of AA on human dermal papilla cells (hDPCs) and hair shaft elongation was evaluated by MTT assay and hair follicle organ culture, respectively. The expression of various growth and survival factors in hDPCs were investigated by western blot or immunohistochemistry. The ability of AA to induce and prolong anagen phase in C57BL/6 mice was analyzed. Results AA was found to enhance the viability of hDPCs and promote the expression of several factors responsible for hair growth, including fibroblast growth factor-7 (FGF-7) and FGF-10. Western blotting identified the role of AA in the phosphorylation of various transcription factors (ERK, CREB, and AKT) and increased expression of Bcl-2 in hDPCs. In addition, AA significantly promoted hair shaft elongation, with increased proliferation of matrix keratinocytes, during ex vivo hair follicle culture. It was also found to promote hair growth by induction and prolongation of anagen phase in telogen-stage C57BL/6 mice. Conclusion This study concludes that AA plays a role in promoting hair growth by increasing the expression of growth factors in hDPCs and enhancing follicle proliferation and survival. PMID:26848219

  8. Arachidonic acid release mediated by OX1 orexin receptors

    PubMed Central

    Turunen, Pauli M; Ekholm, Marie E; Somerharju, Pentti; Kukkonen, Jyrki P

    2010-01-01

    Background and purpose: We have previously shown that lipid mediators, produced by phospholipase D and C, are generated in OX1 orexin receptor signalling with high potency, and presumably mediate some of the physiological responses to orexin. In this study, we investigated whether the ubiquitous phospholipase A2 (PLA2) signalling system is also involved in orexin receptor signalling. Experimental approach: Recombinant Chinese hamster ovary-K1 cells, expressing human OX1 receptors, were used as a model system. Arachidonic acid (AA) release was measured from 3H-AA-labelled cells. Ca2+ signalling was assessed using single-cell imaging. Key results: Orexins strongly stimulated [3H]-AA release (maximally 4.4-fold). Orexin-A was somewhat more potent than orexin-B (pEC50= 8.90 and 8.38 respectively). The concentration–response curves appeared biphasic. The release was fully inhibited by the potent cPLA2 and iPLA2 inhibitor, methyl arachidonyl fluorophosphonate, whereas the iPLA2 inhibitors, R- and S-bromoenol lactone, caused only a partial inhibition. The response was also fully dependent on Ca2+ influx, and the inhibitor studies suggested involvement of the receptor-operated influx pathway. The receptor-operated pathway, on the other hand, was partially dependent on PLA2 activity. The extracellular signal-regulated kinase, but not protein kinase C, were involved in the PLA2 activation at low orexin concentrations. Conclusions and implications: Activation of OX1 orexin receptors induced a strong, high-potency AA release, possibly via multiple PLA2 species, and this response may be important for the receptor-operated Ca2+ influx. The response coincided with other high-potency lipid messenger responses, and may interact with these signals. PMID:20002100

  9. Playing by Ear: Foundation or Frill?

    ERIC Educational Resources Information Center

    Woody, Robert H.

    2012-01-01

    Many people divide musicians into two types: those who can read music and those who play by ear. Formal music education tends to place great emphasis on producing musically literate performers but devotes much less attention to teaching students to make music without notation. Some would suggest that playing by ear is a specialized skill that is…

  10. INNER EAR EMBRYOGENESIS: GENETIC AND ENVIRONMENTAL DETERMINANTS

    EPA Science Inventory

    The anatomy and developmental molecular genetics of the inner ear from establishment of the otic placode to formation of the definitive cochlea and vestibular apparatus will be reviewed and the complex 3-D structural changes that shape the developing inner ear will be illustrated...

  11. Middle ear malformations in identical twins.

    PubMed

    Kidowaki, Naoko; Kamitani, Toru; Nakamura, Takashi; Taki, Masakatsu; Sakaguchi, Hirofumi; Suzuki, Toshihiro; Hisa, Yasuo

    2014-06-01

    The majority of the congenital anomalies of middle ear are solitary and a non-hereditary. We report cases of identical twins with congenital incudo-stapedial disconnection. Case 1 was an 8-year-old girl. Hearing impairment was identified at the age of three. She was referred to our university hospital in April 2005. Pure-tone audiogram showed conductive hearing impairments. Computed tomography (CT) revealed the incudo-stapedial disconnections in both ears. The exploratory tympanotomies on the right and left ears were performed in May and July 2005, respectively. The surgical findings showed absence of the long process and presence of the lenticular process of the incus in both ears. After the reconstructions of ossicular chain, the hearing of both ears improved. Case 2 was an 11-year-old girl. The hearing impairment of the right ear was identified in May 2008. She was referred to our university hospital three months later. Pure-tone audiogram showed the conductive hearing impairment in the right ear. CT revealed the incudo-stapedial disconnection in the right ear. The surgery showed the same findings as those of case 1. Anomalies of both cases suggest that the lenticular process of the incus and the stapes originate from a common primordium. PMID:24355584

  12. Playing by Ear: Foundation or Frill?

    ERIC Educational Resources Information Center

    Woody, Robert H.

    2012-01-01

    Many people divide musicians into two types: those who can read music and those who play by ear. Formal music education tends to place great emphasis on producing musically literate performers but devotes much less attention to teaching students to make music without notation. Some would suggest that playing by ear is a specialized skill that is

  13. Arachidonic acid hydroperoxide stimulates lipid peroxidation in rat liver nuclei and chromatin fractions.

    PubMed

    Marmunti, Mnica; Catal, Angel

    2007-04-01

    Arachidonic acid, the most abundant polyunsaturated fatty acid in rat liver nuclei phospholipids is a major target of free radical attack, which induces lipid peroxidation. The non-enzymatic lipid peroxidation process in intact rat liver nuclei and in several chromatin fractions indicated that the most sensitive fatty acid for peroxidation is arachidonic acid C20:4 n-6. In this study, the effect of different amounts of arachidonic acid hydroperoxide on the lipid peroxidation of rat liver nuclei and chromatin fractions was studied; rat liver nuclei and chromatin fractions deprived of exogenous added hydroperoxide were utilized as control. The addition of arachidonic acid hydroperoxide to liver nuclei produces a marked increase in light emission that was hydroperoxide concentration dependent. The maximal peak of chemiluminescence displayed by the different chromatin fractions analyzed was observed between 20 and 80 min of incubation. The highest value of light emission was displayed by the high-density chromatin fractions, the 27.5 K fraction showed intermediate values of light emission, whereas the lowest density fraction produced very low chemiluminescence. A high correlation between arachidonic acid hydroperoxide concentration and chemiluminescence in the different chromatin fractions was observed. PMID:17136439

  14. The stimulation of arachidonic acid metabolism in human platelets by hydrodynamic stresses

    NASA Technical Reports Server (NTRS)

    Rajagopalan, Sridhar; Mcintire, Larry V.; Hall, Elizabeth R.; Wu, Kenneth K.

    1988-01-01

    The effects of stimulating human platelets by thrombin and by hydrodynamic stresses on the platelets' arachidonic acid metabolism were investigated using (1-C-14)-arachidonic acid label and a specially designed viscometer that ensured laminar shear flow with a nearly uniform shear rate throughout the flow region. It was found that platelets activated by thrombin formed principally thromboxane A2, 12-hydroxy 5,8,10-heptadecatrienoic acid and 12-hydroxy 5,8,10,14-eicosatetraenoic acid (12-HETE). On the other hand, platelets activated by shear, formed only 12-HETE (although arachidonic acid metabolism was stimulated); no cyclooxygenase metabolites were detected. Results indicate that platelets may greatly increase their 12-HETE production when activated by passage through a high-stress region of the circulation, such as an atherosclerotic stenosis.

  15. Effect of progesterone on the release of arachidonic acid from human endometrial cells stimulated by histamine

    SciTech Connect

    Wilson, T.; Liggins, G.C.; Aimer, G.P.; Watkins, E.J.

    1986-02-01

    Progesterone at concentrations of 10(-7)M and 10(-8)M inhibits release of (/sup 3/H)-arachidonic acid from stimulated, perfused, endometrial cells. The effect is independent of the mechanism of stimulation. Cortisol (10(-5)M but not 10(-7)M) has a similar effect in this system but estradiol (10(-7)M) is without effect. There was a positive correlation (p less than 0.05) between the magnitude of inhibition by progesterone and the day of cycle. The inhibitory action of progesterone on the release of arachidonic acid was greater in endometrial cells than in decidual cells and was apparent after fifteen minutes. The activities of commercial and endometrial cell-free preparations of phospholipase A2 and phospholipase C were unaffected by the presence of progesterone. We conclude that progesterone modulates release of (/sup 3/H)-arachidonic acid from endometrial cells by a rapid, indirect action on phospholipase activity.

  16. Evidence for, and taxonomic value of, an arachidonic acid cascade in the Lipomycetaceae.

    PubMed

    Kock, J L; Coetzee, D J; van Dyk, M S; Truscott, M; Botha, A; Augustyn, O P

    1992-11-01

    By using specific inhibitors of the lipoxygenase and cyclo-oxygenase pathways, arachidonic acid metabolites with similar sensitivities towards these inhibitors as in humans, were detected in Dipodascopsis uninucleata. The taxonomic value of aspirin sensitive arachidonic acid metabolites in the Lipomycetaceae was next assessed. No metabolites of which the production is inhibited by aspirin were detected in strains representing the following species: Lipomyces starkeyi, Lipomyces kononenkoae, Lipomyces tetrasporus, Myxozyma melibiosi, Myxozyma mucilagina, Myxozyma kluyveri, Waltomyces lipofer, Zygozyma oligophaga and Zygozyma arxii. The detection of such aspirin sensitive arachidonic acid metabolites in representative strains of Lipomyces anomalus and the genus Dipodascopsis, emphasises the isolated position of these taxa in the genus Lipomyces and the family Lipomycetaceae, respectively. Finally using long chain fatty acid analyses, electrophoretic karyotyping and other phenotypic characters, a phylogenetic scheme is proposed for some genera in the Lipomycetaceae. PMID:1285641

  17. Effects of middle-ear disorders on power reflectance measured in cadaveric ear canals

    PubMed Central

    Merchant, Gabrielle R.; Horton, Nicholas J.

    2011-01-01

    Objective Reflectance measured in the ear canal offers a noninvasive method to monitor the acoustic properties of the middle ear, and few systematic measurements exist on the effects of various middle-ear disorders on the reflectance. This work utilizes a human cadaver-ear preparation and a mathematical middle-ear model to both measure and predict how power reflectance ? is affected by the middle-ear disorders of static middle-ear pressures, middle-ear fluid, fixed stapes, disarticulated incudo-stapedial joint, and tympanic-membrane perforations. Design ? was calculated from ear-canal pressure measurements made on human-cadaver ears in the normal condition and five states: (1) positive and negative pressure in the middle-ear cavity, (2) fluid-filled middle ear, (3) stapes fixed with dental cement, (4) incudo-stapedial joint disarticulated, and (5) tympanic-membrane perforations. The middle-ear model of Kringlebotn (1988) was modified to represent the middle-ear disorders. Model predictions are compared to measurements. Results For a given disorder, the general trends of the measurements and model were similar. The changes from normal in ?, induced by the simulated disorder, generally depend on frequency and the extent of the disorder (except for the disarticulation). Systematic changes in middle-ear static pressure (up to 300 daPa) resulted in systematic increases in ?. These affects were most pronounced for frequencies up to 1000 to 2000 Hz. Above about 2000 Hz there were some asymmetries in behavior between negative and positive pressures. Results with fluid in the middle-ear air space were highly dependent on the percentage of the air space that was filled. Changes in ? were minimal when a smaller fraction of the air space was filled with fluid, and as the air space was filled with more saline, ? increased at most frequencies. Fixation of the stapes generally resulted in a relatively small low-frequency increase in ?. Disarticulation of the incus with the stapes led to a consistent low-frequency decreases in ? with a distinctive minimum below 1000 Hz. Perforations of the tympanic membrane resulted in a decrease in ? for frequencies up to about 2000 Hz; at these lower frequencies, smaller perforations led to larger changes from normal as compared to larger perforations. Conclusions These preliminary measurements help assess the utility of power reflectance as a diagnostic tool for middle-ear disorders. In particular, the measurements document (1) the frequency ranges for which the changes are largest and (2) the extent of the changes from normal for a spectrum of middle-ear disorders. PMID:22037477

  18. Protein kinase C, arachidonate metabolism, and tracheal smooth muscle - effects of temperature

    SciTech Connect

    Huang, C.; Baraban, J.; Menkes, H.

    1986-03-01

    Cooling causes airway obstruction in asthma. Contractions of airway smooth muscle may be produced through the phosphatidylinositol cycle and the activation of protein kinase C. Protein kinase C can be activated directly with phorbol esters. The authors studied the effects of temperature on responses to phorbol 12,13-diacetate (PDA) in guinea pig tracheal rings bathed in Krebs-Henseleit solution. At 37/sup 0/C, 1 ..mu..M PDA relaxed the tissue (tension fell 0.60 +/- S.E. 0.04 g). At 27/sub 0/C, 1 ..mu..M PDA contracted the tissue (tension rose 0.050 +/- 0.05 g). In comparison, near maximum contractions produced by 4 ..mu..M carbachol were 2.00 +/- 0.09 g at 37/sub 0/C and 1.90 +/- 0.09 g at 27/sup 0/C. Butler-Gralla et al. showed that phorbol esters may stimulate the release of arachidonic acid from cultured cells. In order to determine whether arachidonate metabolites play a role in responses observed in guinea pig trachea, the authors used indomethacin (a cyclooxygenase inhibitor), FPL 55712 (a leukotriene receptor antagonist) and Na arachidonate. At 37/sup 0/C, 3 ..mu..M indomethacin pretreatment abolished relaxationby 1 uM PDA. At 27/sup 0/C, 10 uM FPL 55712 pretreatment abolished contractions by 1 ..mu..M PDA. Like PDA, 1 ..mu..M Na arachidonate produced relaxation at 37/sup 0/C and contraction at 27/sup 0/C. The authors conclude that the effects of PDA at different temperatures parallel the effects of Na arachidonate. These results suggest that the effects of PDA in the guinea pig trachea are related to the release of endogenous arachidonic acid and that the cyclooxygenase pathway predominates at high temperature and the lipoxygenase pathway predominates at low temperature.

  19. The effect of fluid mechanical stress on cellular arachidonic acid metabolism

    NASA Technical Reports Server (NTRS)

    Mcintire, L. V.; Frangos, J. A.; Rhee, B. G.; Eskin, S. G.; Hall, E. R.

    1987-01-01

    The effect of sublytic levels of mechanical perturations of cells on cell metabolism were investigated by analyzing the products of arachidonic acid (used as a marker metabolite) in blood platelets, polymorphonuclear leucocytes, and cultured umbilical-vein endothelial cells after the suspensions of these cells were subjected to a shear stress in a modified viscometer. It is shown that the sublytic levels of mechanical stress stimulated the arachidonic acid metabolism in all these cell types. Possible biological implications of this stress-metabolism coupling are discussed.

  20. Arachidonic acid activation of a new family of K+ channels in cultured rat neuronal cells.

    PubMed Central

    Kim, D; Sladek, C D; Aguado-Velasco, C; Mathiasen, J R

    1995-01-01

    1. The presence and properties of K+ channels activated by arachidonic acid were studied in neuronal cells cultured from the mesencephalic and hypothalamic areas of rat brain. 2. Arachidonic acid produced a concentration-dependent (5-50 microM) and reversible activation of whole-cell currents. 3. In excised membrane patches, arachidonic acid applied to the cytoplasmic or extracellular side of the membrane caused opening of three types of channels whose current-voltage relationships were slightly outwardly rectifying, inwardly rectifying and linear, and whose single channel slope conductances at +60 mV were 143, 45 and 52 pS, respectively. 4. All three currents were K+ selective and blocked by 2 mM Ba2+ but not by other K+ channel blockers such as tetraethylammonium chloride, 4-aminopyridine and quinidine. The outwardly and inwardly rectifying currents were slightly voltage dependent with higher channel activity at more depolarized potentials. 5. Arachidonic acid activated the K+ channels in cells treated with cyclo-oxygenase and lipoxygenase inhibitors (indomethacin and nordihydroguaiaretic acid), indicating that arachidonic acid itself can directly activate the channels. Alcohol and methyl ester derivatives of arachidonic acid failed to activate the K+ channels, indicating that the charged carboxyl group is important for activation. 6. Certain unsaturated fatty acids (linoleic, linolenic and docosahexaenoic acids), but not saturated fatty acids (myristic, palmitic, stearic acids), also reversibly activated all three types of K+ channel. 7. All three K+ channels were activated by pressure applied to the membrane (i.e. channels were stretch sensitive) with a half-maximal pressure of approximately 18 mmHg. The K+ channels were not blocked by 100 microM GdCl3. 8. A decrease in intracellular pH (over the range 5.6-7.2) caused a reversible, pH-dependent increase in channel activity whether the channel was initially activated by arachidonic acid or stretch. 9. Glutamate, a neurotransmitter reported to generate arachidonic acid in striatal neurons, did not cause activation of the K+ channels when applied extracellularly in cell-attached patches. 10. It is suggested that the K+ channels described here belong to a distinct family of ion channels that are activated by either fatty acids or membrane stretch. Although the physiological roles of these K+ channels are not yet known, they may be involved in cellular processes such as cell volume regulation and ischaemia-induced elevation of K+ loss. Images Figure 1 PMID:7623282

  1. Surgical Management of Ear Diseases in Rabbits.

    PubMed

    Csomos, Rebecca; Bosscher, Georgia; Mans, Christoph; Hardie, Robert

    2016-01-01

    Otitis externa and media are frequently diagnosed disorders in rabbits and are particularly common in lop-eared breeds because of the specific anatomy of the ear canal. Medical management for otitis externa and media often provides only a temporary improvement in clinical signs. Surgery by means of partial or total ear canal ablation (PECA or TECA) combined with lateral bulla osteotomy (LBO) represents a feasible approach that is well tolerated and provides a good clinical outcome. Short-term complications associated with PECA/TECA-LBO include facial nerve paralysis and vestibular disease. PMID:26611929

  2. Tranexamic acid induces kaolin intake stimulating a pathway involving tachykinin neurokinin 1 receptors in rats.

    PubMed

    Kakiuchi, Hitoshi; Kawarai-Shimamura, Asako; Kuwagata, Makiko; Orito, Kensuke

    2014-01-15

    Tranexamic acid suppresses post-partum haemorrhage and idiopathic menorrhagia through its anti-fibrinolytic action. Although it is clinically useful, it is associated with high risks of side effects such as emesis. Understanding the mechanisms underlying tranexamic acid-induced emesis is very important to explore appropriate anti-emetic drugs for the prevention and/or suppression of emesis. In this study, we examined the receptors involved in tranexamic acid-induced kaolin intake in rats, which reflects the drug's clinical emetogenic potential in humans. Further, we examined the brain regions activated by administration of tranexamic acid and elucidated pivotal pathways of tranexamic acid-induced kaolin intake. We examined the effects of ondansetron, a 5-hydroxytryptamine 3 receptor antagonist, domperidone, a dopamine 2 receptor antagonist, and aprepitant, a tachykinin neurokinin 1 (NK1) receptor antagonist, on tranexamic acid-induced kaolin intake in rats. Then, we determined the brain regions that showed increased numbers of c-Fos immunoreactive cells. Finally, we examined the effects of an antagonist(s) that reduced tranexamic acid-induced kaolin intake on the increase in c-Fos immunoreactive cells. Aprepitant significantly decreased tranexamic acid-induced kaolin intake. However, neither ondansetron nor domperidone decreased kaolin intake. Tranexamic acid significantly increased c-Fos immunoreactive cells by approximately 5.5-fold and 22-fold in the area postrema and nucleus of solitary tract, respectively. Aprepitant decreased the number of c-Fos immunoreactive cells in both areas. Tranexamic acid induced kaolin intake possibly via stimulation of tachykinin NK1 receptors in rats. The tachykinin NK1 receptor could be targeted to prevent and/or suppress emesis in patients receiving tranexamic acid. PMID:24333477

  3. Mozart ear: diagnosis, treatment, and literature review.

    PubMed

    Yamashita, Ken; Yotsuyanagi, Takatoshi; Saito, Tamotsu; Isogai, Noritaka; Mori, Hiromasa; Itani, Yoshihito

    2011-11-01

    Mozart ear is a congenital auricular deformity, which is mainly characterized by a bulging appearance of the anterosuperior portion of the auricle, a convexly protruded cavum conchae, and a slit-like narrowing of the orifice of the external auditory meatus. It is said to be uncommon, and because no one has yet fully described neither the disease nor the treatment, the concept of Mozart ear has not been unified. This report describes a case of a 13-year-old girl presented with an unusual congenital deformity which showed the features of Mozart ear. It is an extremely rare deformity that only about 4 clinical cases have been reported in medical literature thereby a treatment method has not been fully discussed. For surgical correction of our cases, we excised deformed conchal cartilage, turned it over, regrafted, and maintained a cosmetically positive result. We also reviewed and described the origin, current concept, and treatment method of Mozart ear. PMID:21587051

  4. Design Factors and Use of Ear Protection*

    PubMed Central

    Rice, C. G.; Coles, R. R. A.

    1966-01-01

    The problems of protecting the ear against hazardous noise are the subject of a general review, supported where relevant by data from the authors' own researches. Ear protectors are classified into two main types?plugs and muffsand the general principles of their function and limitations are stated. Examples of representative ear protectors are given in more detail, with particular respect to their relative merits and pure-tone attenuation characteristics. The effects of earplugs on speech communication are considered and the relationships between pure-tone attenuation and protection against continuous noise are discussed in some detail. The results of temporary threshold shift (T.T.S.) reduction studies of the efficiency of V.51R and Selectone-K earplugs in protecting against reverberant and non-reverberant impulsive noises are presented. The design requirements of ear protectors and some of the problems created by them are also outlined. Images PMID:5946129

  5. [Middle ear effusion and allergy in childhood].

    PubMed

    Bachert, C; Keilmann, A; Ganzer, U

    1989-04-01

    Besides mechanical or infectious factors in the genesis of secretory otitis media IgE-mediated hypersensitivity has often been discussed. In order to estimate the importance of an allergic reaction in the development of middle ear disease, we examined 27 children having adenoids and a secretory otitis media. We documented the patients' history of allergy and determined the IgE-levels in the serum, the middle ear effusions and the adenoid tissue. 5 out of 27 children suffered from an allergy of the upper respiratory tract, but only in one child we found an elevated level of IgE in middle ear effusion. On the basis of our investigations and recent literature, we suggest that an allergic rhinitis might cause an Eustachian tube dysfunction in a few patients. There is no evidence of a local allergic reaction of the middle ear mucosa. PMID:2742640

  6. 21 CFR 874.4140 - Ear, nose, and throat bur.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat bur. 874.4140 Section 874...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4140 Ear, nose, and throat bur. (a) Identification. An ear, nose, and throat bur is a device consisting of an interchangeable drill bit that...

  7. 38 CFR 4.87 - Schedule of ratings-ear.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2011-07-01 2011-07-01 false Schedule of ratings-ear...—ear. Diseases of the Ear Rating 6200Chronic suppurative otitis media, mastoiditis, or cholesteatoma... of the substance 10 6208Malignant neoplasm of the ear (other than skin only) 100 Note: A rating...

  8. 21 CFR 874.4140 - Ear, nose, and throat bur.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat bur. 874.4140 Section 874...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4140 Ear, nose, and throat bur. (a) Identification. An ear, nose, and throat bur is a device consisting of an interchangeable drill bit that...

  9. 21 CFR 874.3430 - Middle ear mold.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food... DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is intended to be implanted to reconstruct the middle...

  10. 38 CFR 4.87 - Schedule of ratings-ear.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2014-07-01 2014-07-01 false Schedule of ratings-ear...—ear. Diseases of the Ear Rating 6200Chronic suppurative otitis media, mastoiditis, or cholesteatoma... of the substance 10 6208Malignant neoplasm of the ear (other than skin only) 100 Note: A rating...

  11. 21 CFR 874.3430 - Middle ear mold.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food... DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is intended to be implanted to reconstruct the middle...

  12. 21 CFR 874.3430 - Middle ear mold.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food... DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is intended to be implanted to reconstruct the middle...

  13. 21 CFR 874.4140 - Ear, nose, and throat bur.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat bur. 874.4140 Section 874...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4140 Ear, nose, and throat bur. (a) Identification. An ear, nose, and throat bur is a device consisting of an interchangeable drill bit that...

  14. 38 CFR 4.87 - Schedule of ratings-ear.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2012-07-01 2012-07-01 false Schedule of ratings-ear...—ear. Diseases of the Ear Rating 6200Chronic suppurative otitis media, mastoiditis, or cholesteatoma... of the substance 10 6208Malignant neoplasm of the ear (other than skin only) 100 Note: A rating...

  15. 21 CFR 874.4140 - Ear, nose, and throat bur.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat bur. 874.4140 Section 874...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4140 Ear, nose, and throat bur. (a) Identification. An ear, nose, and throat bur is a device consisting of an interchangeable drill bit that...

  16. 38 CFR 4.87 - Schedule of ratings-ear.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2013-07-01 2013-07-01 false Schedule of ratings-ear...—ear. Diseases of the Ear Rating 6200Chronic suppurative otitis media, mastoiditis, or cholesteatoma... of the substance 10 6208Malignant neoplasm of the ear (other than skin only) 100 Note: A rating...

  17. 38 CFR 4.87 - Schedule of ratings-ear.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Schedule of ratings-ear...—ear. Diseases of the Ear Rating 6200Chronic suppurative otitis media, mastoiditis, or cholesteatoma... of the substance 10 6208Malignant neoplasm of the ear (other than skin only) 100 Note: A rating...

  18. 21 CFR 874.3430 - Middle ear mold.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food... DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is intended to be implanted to reconstruct the middle...

  19. 21 CFR 874.4140 - Ear, nose, and throat bur.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat bur. 874.4140 Section 874...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4140 Ear, nose, and throat bur. (a) Identification. An ear, nose, and throat bur is a device consisting of an interchangeable drill bit that...

  20. 21 CFR 874.3430 - Middle ear mold.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food... DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is intended to be implanted to reconstruct the middle...

  1. Ear Infections in Autistic and Normal Children. Brief Report.

    ERIC Educational Resources Information Center

    Konstantareas, M. Mary; Homatidis, Soula

    1987-01-01

    Evaluation of the frequency of ear infections, ear tube drainage, and deafness for 51 autistic children (ages 2-18) indicated that autistic children had a greater incidence of ear infections than matched normal peers and lower functioning children had an earlier onset of ear infections than higher functioning autistic peers. (Author)

  2. An analysis of the acoustic input impedance of the ear.

    PubMed

    Withnell, Robert H; Gowdy, Lauren E

    2013-10-01

    Ear canal acoustics was examined using a one-dimensional lossy transmission line with a distributed load impedance to model the ear. The acoustic input impedance of the ear was derived from sound pressure measurements in the ear canal of healthy human ears. A nonlinear least squares fit of the model to data generated estimates for ear canal radius, ear canal length, and quantified the resistance that would produce transmission losses. Derivation of ear canal radius has application to quantifying the impedance mismatch at the eardrum between the ear canal and the middle ear. The length of the ear canal was found, in general, to be longer than the length derived from the one-quarter wavelength standing wave frequency, consistent with the middle ear being mass-controlled at the standing wave frequency. Viscothermal losses in the ear canal, in some cases, may exceed that attributable to a smooth rigid wall. Resistance in the middle ear was found to contribute significantly to the total resistance. In effect, this analysis "reverse engineers" physical parameters of the ear from sound pressure measurements in the ear canal. PMID:23917695

  3. Middle ear muscles of the frog.

    PubMed Central

    Wever, E G

    1979-01-01

    The anuran middle ear in its complete form includes two skeletal elements, the columella and operculum, each occupying a portion of the oval window of the otic capsule and each provided with a middle ear muscle. The two elements have an interlocking arrangement of a form that makes it possible for these muscles to exercise a high degree of control of sound transmission from tympanic membrane to inner ear receptors. From the anatomical relations it is inferred that the two muscles operate as antagonists so that contraction of the opercular muscle and relaxation of the columellar muscle leave the columella free to move in and out of the oval window in response to sound vibrations, whereas a contraction of the columellar muscle and relaxation of the opercular muscle tend to immobilize the columella and reduce the transmission inward. The frog thus achieves a degree of control of sound reception that probably is unmatched among vertebrate ears. The purpose of the middle ear mechanism is no doubt the protection of the inner ear receptors (the amphibian and basilar papillae) from overstimulation by sounds, including the animal's own cries and the intense clamor produced by a group of frogs calling in chorus. Images PMID:288086

  4. CHEMICAL NATURE AND IMMUNOTOXICOLOGICAL PROPERTIES OF ARACHIDONIC ACID DEGRADATION PRODUCTS FORMED BY EXPOSURE TO OZONE

    EPA Science Inventory

    Ozone (O3) exposure in vivo has been reported to degrade arachidonic acid (AA) in the lungs of rodents. The O3-degraded AA products may play a role in the lung responses to this toxicant. In order to study the chemical nature and biological activity of O3-exposed AA, we exposed A...

  5. Arachidonic acid and docosahexaenoic acid are increased in human colorectal cancer.

    PubMed Central

    Neoptolemos, J P; Husband, D; Imray, C; Rowley, S; Lawson, N

    1991-01-01

    Increased arachidonic acid concentrations in experimental rodent colonic cancer have been described recently. In humans, a reduced erythrocyte stearic acid to oleic acid ratio has been reported in patients with colorectal cancer and it has been proposed that similar changes exist in the cancer tissue. The long chain fatty acids in the cancers of 15 patients with colorectal cancer were measured and compared with values in the unaffected mucosa. The values were expressed as mean (SD) mg fatty acid/g tissue and compared by analysis of variance. In the cancer tissue arachidonic acid was increased (0.703 (0.109) mg/g v 0.603 (0.127) mg/g, p less than 0.05) as was docosahexaenoic acid (0.211 (0.066) mg/g v 0.148 (0.039) mg/g, p less than 0.001). In contrast, the stearic acid to oleic acid ratio in the cancer tissue was increased rather than decreased, as previously suggested (0.36 (0.05) v 0.29 (0.7), p less than 0.01). Increased arachidonic acid and docosahexaenoic acid concentrations may be related to reduced lipid peroxidation, which is a feature of rapidly growing cells. Alternatively, the increased arachidonic acid values could be due to enhanced desaturase activity upon linoleic and linolenic acid, leading perhaps to increased formation of prostaglandins and other lipoxygenase products. PMID:1826490

  6. Amyloid Plaque-Associated Oxidative Degradation of Uniformly Radiolabeled Arachidonic Acid.

    PubMed

    Furman, Ran; Murray, Ian V J; Schall, Hayley E; Liu, Qiwei; Ghiwot, Yonatan; Axelsen, Paul H

    2016-03-16

    Oxidative stress is a frequently observed feature of Alzheimer's disease, but its pathological significance is not understood. To explore the relationship between oxidative stress and amyloid plaques, uniformly radiolabeled arachidonate was introduced into transgenic mouse models of Alzheimer's disease via intracerebroventricular injection. Uniform labeling with carbon-14 is used here for the first time, and made possible meaningful quantification of arachidonate oxidative degradation products. The injected arachidonate entered a fatty acid pool that was subject to oxidative degradation in both transgenic and wild-type animals. However, the extent of its degradation was markedly greater in the hippocampus of transgenic animals where amyloid plaques were abundant. In human Alzheimer's brain, plaque-associated proteins were post-translationally modified by hydroxynonenal, a well-known oxidative degradation product of arachidonate. These results suggest that several recurring themes in Alzheimer's pathogenesis, amyloid β proteins, transition metal ions, oxidative stress, and apolipoprotein isoforms, may be involved in a common mechanism that has the potential to explain both neuronal loss and fibril formation in this disease. PMID:26800372

  7. Arachidonate 5-lipoxygenase gene variants affect response to fish oil supplementation by healthy African Americans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objective: To determine the effects of arachidonate 5-lipoxygenase gene (ALOX5) variants on plasma lipid and lipoprotein concentrations and changes in response to fish oil supplementation. We hypothesized that Sp1 variants in the ALOX5 promoter, which have previously been associated with cardiovascu...

  8. Ozone-induced alterations in arachidonic acid metabolism in cultured lung cell types

    SciTech Connect

    Madden, M.C.

    1986-01-01

    One of the most sensitive cells to ozone (O/sub 3/) damage is the pulmonary endothelial cell which may mediate the response of the lung to injury by productions of the autacoid prostacyclin (PGl/sub 2/), a metabolite of arachidonic acid. Exposure of endothelial cell cultures to ozone produced a concentration dependent decreases in the synthesis of PGl/sub 2/. Release of /sup 3/H-arachidonic acid from endothelial cells was increased after two hours of 0.3 and 1.0 ppm O/sub 3/ exposure while incubation of cells with 20 ..mu..M and arachidonate (4 min) after exposure resulted in a decreased PGl/sub 2/ synthesis. Cells exposed to 1.0 ppm O/sub 3/ did not have a decreased PGl/sub 2/ production when incubated with 5 ..mu..M PGH/sub 2/ immediately after exposure. These results are consistent with an O/sub 3/-induced inhibition of cyclooxygenase activity. O/sub 3/ exposure (1.0 ppm) produced a rapid decrease in endothelial PGl/sub 2/ synthesis. The data suggest that cyclooxygenase was not inactivated by increased autooxidation due to metabolism of increased free arachidonate. PGl/sub 2/ synthesis returned to control amounts within 12 hours after ozone exposure similar to the recovery time of irreversibly inhibited cyclooxygenase suggesting that recovery was due to de novo synthesis of enzyme. Lipid peroxides and/or hydrogen peroxide (H/sub 2/O/sub 2/) may have caused the inhibition of cyclooxygenase. Incubation of cells with catalase (5 U/ml) protected against the O/sub 3/-induced depression in PGl/sub 2/ synthesis. Exogenously added H/sub 2/O/sub 2/ (greater than or equal to 75 ..mu..M) caused a stimulation of basal PGl/sub 2/ production but depressed arachidonate-stimulated synthesis. O/sub 3/ exposure (2 hr, 1.0 ppm) produced altered metabolism of arachidonate in other important lung cell types, e.g., a decreased PGl/sub 2/ synthesis in smooth muscle cultures. Exposure of lung macrophages to O/sub 3/ caused an increase in almost all arachidonate metabolites produced.

  9. Identification of Novel Endogenous Cytochrome P450 Arachidonate Metabolites with High Affinity for Cannabinoid Receptors*

    PubMed Central

    Chen, Jian-Kang; Chen, Jianchun; Imig, John D.; Wei, Shouzuo; Hachey, David L.; Guthi, Jagadeesh Setti; Falck, John R.; Capdevila, Jorge H.; Harris, Raymond C.

    2008-01-01

    Arachidonic acid is an essential constituent of cell membranes that is esterified to the sn-2-position of glycerophospholipids and is released from selected lipid pools by phospholipase cleavage. The released arachidonic acid can be metabolized by three enzymatic pathways: the cyclooxygenase pathway forming prostaglandins and thromboxanes, the lipoxygenase pathway generating leukotrienes and lipoxins, and the cytochrome P450 (cP450) pathway producing epoxyeicosatrienoic acids and hydroxyeicosatetraenoic acids. The present study describes a novel group of cP450 epoxygenase-dependent metabolites of arachidonic acid, termed 2-epoxyeicosatrienoylglycerols (2-EG), including two regioisomers, 2-(11,12-epoxyeicosatrienoyl)glycerol (2-11,12-EG) and 2-(14,15-epoxyeicosatrienoyl)glycerol (2-14,15-EG), which are both produced in the kidney and spleen, whereas 2-11,12-EG is also detected in the brain. Both 2-11,12-EG and 2-14,15-EG activated the two cannabinoid (CB) receptor subtypes, CB1 and CB2, with high affinity and elicited biological responses in cultured cells expressing CB receptors and in intact animals. In contrast, the parental arachidonic acid and epoxyeicosatrienoic acids failed to activate CB1 or CB2 receptors. Thus, these cP450 epoxygenase-dependent metabolites are a novel class of endogenously produced, biologically active lipid mediators with the characteristics of endocannabinoids. This is the first evidence of a cytochrome P450-dependent arachidonate metabolite that can activate G-protein-coupled cell membrane receptors and suggests a functional link between the cytochrome P450 enzyme system and the endocannabinoid system. PMID:18606824

  10. Uptake and release of arachidonic acid by platelets and cultured cells

    SciTech Connect

    Neufeld, E.J.

    1985-01-01

    The release by thrombin of arachidonic acid, and the accompanying phospholipid metabolism, were studied in human platelets. At 23/sup 0/C, arachidonate release was half-maximal by 10-30 sec after stimulation, and preceded substantial increase in phosphatidic acid (PA) mass. (/sup 3/H)-glycerol-labeled platelets synthesized phospholipids from (/sup 3/H) PA at a rate of 0.08-0.3 nmol/min/10/sup 9/ cells at 37/sup 0/C. This rate of PA turnover was not enhanced by thrombin stimulation. Thus, an increase in PA mass is not a necessary event in the pathway loading to arachidonate release, and the release of several nmol of arachidonate from PI in the first minute after thrombin stimulation could not have arisen via PA as an intermediate. Biological function of arachidonate-specific acyl-CoA synthetase was examined in platelets and in HSDM/sub 1/C/sub 1/ murine fibrosarcoma cells. Washed platelets were found to take up and esterify into cellular phospholipids eicosanoid precursor fatty acids present at concentrations of 5-500 nM. The uptake process was saturable with respect to fatty acid concentration, with apparent K/sub m/ less than or equal to 85 nM. Stearate, oleate and linoleate were taken up less rapidly, and with higher apparent K/sub m/'s (greater than or equal to 170 nM). High affinity uptake was also found in HSDM/sub 1/C/sub 1/ cells. The fatty acid structural requirements of arachidonoyl-CoA synthetase were examined. Among common mammalian fatty acids, only eicosanoid precursors and docosahexaenoate could serve as substrates. These studies strongly suggest that the synthetase is required for normal eicosanoid homeostasis.

  11. Sensitization of group III muscle afferents to static contraction by arachidonic acid.

    PubMed

    Rotto, D M; Schultz, H D; Longhurst, J C; Kaufman, M P

    1990-03-01

    The afferent arm of the reflex are responsible for the pressor response to static contraction is comprised of group III and IV fibers. The nature of the contraction-induced stimulus activating these fibers remains unclear. Evidence suggests that most group III afferents are sensitive to mechanical stimuli, whereas most group IV afferents are sensitive to metabolic stimuli. Recently, in anesthetized cats, stimulation of group III mechanoreceptors has been shown to have a role in the reflex pressor response to static contraction. In skin, the sensitivity of thin fiber mechanoreceptors to distortion of their receptive fields has been shown to be increased by both cyclooxygenase and lipoxygenase products of arachidonic acid metabolism. Therefore, in barbiturate-anesthetized cats we recorded the responses of group III muscle afferents to static contraction before and after arachidonic acid (1-2 mg ia) and/or indomethacin (5 mg/kg iv). Arachidonic acid increased the responses of group III afferents (n = 11) to contraction by 265% (from 0.17 +/- 0.07 to 0.62 +/- 0.24 impulses/s; P less than 0.025). Indomethacin decreased the responses of group III afferents (n = 9) to contraction by 61% (from 1.00 +/- 0.37 to 0.39 +/- 0.16 impulses/s; P less than 0.025). Arachidonic acid given after indomethacin increased the responses of two of four group III afferents to contraction. We conclude that both cyclooxygenase and lipoxygenase products of arachidonic acid metabolism sensitize group III muscle afferents to static contraction. PMID:2111312

  12. UVB irradiation induces changes in the distribution and release of 14C-arachidonic acid in human keratinocytes in culture.

    PubMed

    Punnonen, K; Puustinen, T; Jansn, C T

    1986-01-01

    Following labeling of human keratinocytes in culture for 48 h with 14C-arachidonic acid (800,000 cpm), 86.8 +/- 0.5% (mean +/- SEM) of the radioactivity was incorporated into the cells. Two hours after exposure to UVB irradiation at doses up to 392 mJ/cm2 of erythemally effective (EE) UVB irradiation, only slight changes in the distribution of arachidonic acid could be detected. However, 24 h after irradiation the release of arachidonic acid into the culture medium was significantly increased. The distribution of arachidonic acid was also changed: there was a considerable loss in the amount of radioactivity associated with phosphatidylethanolamine. With doses up to 174 mJ/cm2 (EE) of UVB, the decrease in the labeling of phospholipids was accompanied by an increased arachidonic acid content in the nonphosphorus lipids, especially in the triacylglycerols. Following a high dose of UVB (392 mJ/cm2, EE), a substantial release of label was detected, but the labeling of triacylglycerols was unaltered. The present study suggests that in human keratinocytes UVB irradiation induces the release of arachidonic acid from the cellular lipids and that the major source of the released arachidonic acid is phosphatidylethanolamine. PMID:2431656

  13. Structure and function of the mammalian middle ear. I: Large middle ears in small desert mammals.

    PubMed

    Mason, Matthew J

    2016-02-01

    Many species of small desert mammals are known to have expanded auditory bullae. The ears of gerbils and heteromyids have been well described, but much less is known about the middle ear anatomy of other desert mammals. In this study, the middle ears of three gerbils (Meriones, Desmodillus and Gerbillurus), two jerboas (Jaculus) and two sengis (elephant-shrews: Macroscelides and Elephantulus) were examined and compared, using micro-computed tomography and light microscopy. Middle ear cavity expansion has occurred in members of all three groups, apparently in association with an essentially 'freely mobile' ossicular morphology and the development of bony tubes for the middle ear arteries. Cavity expansion can occur in different ways, resulting in different subcavity patterns even between different species of gerbils. Having enlarged middle ear cavities aids low-frequency audition, and several adaptive advantages of low-frequency hearing to small desert mammals have been proposed. However, while Macroscelides was found here to have middle ear cavities so large that together they exceed brain volume, the bullae of Elephantulus are considerably smaller. Why middle ear cavities are enlarged in some desert species but not others remains unclear, but it may relate to microhabitat. PMID:26104342

  14. Delayed ear reconstruction: case report of reconstruction of an avulsed ear 2 days after injury.

    PubMed

    Brockhoff, Hans C; Zide, Michael

    2014-07-01

    Auricular reattachment and reconstruction following traumatic ear avulsion is a challenging surgical problem. Suggested reconstruction methods include direct reattachment, composite grafting, pocket methods, coverage with periauricular flaps, and microsurgical repair. A published alternative is reattachment and burial of the amputated part under a postauricular flap. If circumstances delay the surgical intervention, what is a safe window to still consider this form of treatment? In the current report, we present a case of a complete partial ear avulsion, which was reattached in the ER as a free graft. Two days later the cartilage was banked under a postauricular flap. A 22 year-old male had his ear was completely bitten off which was re-attached. Two days later the skin of the avulsed segment was dark and bloodless. The avulsed segment was removed from the ear. The overlying skin was dissected off of the attached ear leaving perichondrium on the medial aspect of the ear. The cartilage was then reattached. A postauricular pocket/flap was created and the ear tucked and secured to the postauricular fascia and skin closed overtop. Five weeks later, the patient had division and inset of the flap with a full thickness skin graft to the posterior aspect of the ear. Our results and experiences suggest that immediate reconstruction may not be crucial. PMID:24793138

  15. Do magnesium infusions protect the inner ear during middle ear surgery? A randomized double blind study.

    PubMed

    Pilgramm, M; Kchy, H P; Schfer, M; Weibel, H P

    1993-01-01

    Joachims et al. recently demonstrated that magnesium was able to protect the inner ear during exposure to noise and fire arms. During middle ear surgery, the inner ear is subjected to noise from fraising and drilling. We saw fit, therefore, to conduct a random double blind study to establish whether magnesium infusions would protect the inner ear during middle ear surgery. We examined 80 patients (38 verum, 42 placebo). The verum patients received 10 mg/kg body weight magnesium 12 hours and 1 hour prior to operation. Plasma and red cell magnesium levels were measured pre-operatively and intra-operatively; they rose as expected. Post-operative auditory tests showed that magnesium had no tendency to prevent inner ear damage. Advocates of magnesium criticize the limited number of patients in our study as well as the administration of the magnesium substitute. In our opinion, however, it should be borne in mind when evaluating these findings that noise from drilling and fraising is only one factor among many which can induce inner ear injury during middle ear surgery. PMID:8460391

  16. An evaluation of tympanometric estimates of ear canal volume.

    PubMed

    Shanks, J E; Lilly, D J

    1981-12-01

    The accuracy of tympanometric estimates of ear canal volume was evaluated by testing the following two assumptions on which the procedure is based: (a) ear canal volume does not change when ear canal pressure is varied, and (b) an ear canal pressure of 200 daPa drives the impedance of the middle ear transmission system to infinity so the immittance measured at 200 daPa can be attributed to the ear canal volume alone. The first assumption was tested by measuring the changes in ear canal volume in eight normal subjects for ear canal pressures between +/- 400 daPa using a manometric procedure based on Boyle's gas law. The data did not support the first assumption. Ear canal volume changed by a mean of .113 ml over the +/- 400 daPa pressure range with slightly larger volume changes occurring for negative ear canal pressures than for positive ear canal pressures. Most of the volume change was attributed to movement of the probe and to movement of the cartilaginous walls of the ear canal. The second assumption was tested by comparing estimates of ear canal volume from susceptance tympanograms with a direct measurement of ear canal volume adjusted for changes in volume due to changes in ear canal pressure between +/- 400 daPa. These data failed to support the second assumption. All tympanometric estimates of ear canal volume were larger than the measured volumes. The largest error (39%) occurred for an ear canal pressure of 200 daPa at 220 Hz, whereas the smallest error (10%) occurred for an ear canal pressure of -400 daPa at 660 Hz. This latter susceptance value (-400 daPa at 660 Hz) divided by three is suggested to correct the 220-Hz tympanogram to the plane of the tympanic membrane. Finally, the effects of errors in estimating ear canal volume on static immittance and on tympanometry are discussed. PMID:7329051

  17. The effect of endogenous essential and nonessential fatty acids on the uptake and subsequent agonist-induced release of arachidonate

    SciTech Connect

    Furth, E.E.; Hurtubise, V.; Schott, M.A.; Laposata, M. )

    1989-11-05

    We have demonstrated that the uptake and agonist-induced release of a pulse of arachidonate are influenced by the size and composition of preexisting endogenous fatty acid pools. EFD-1 cells, an essential fatty acid-deficient mouse fibrosarcoma cell line, were incubated with radiolabeled (14C or 3H) arachidonate, linoleate, eicosapentaenoate (EPA), palmitate, or oleate in concentrations of 0-33 microM for 24 h. After 24 h, the cells were pulsed with 0.67 microM radiolabeled (3H or 14C, opposite first label) arachidonate for 15 min and then stimulated with 10 microM bradykinin for 4 min. Because EFD-1 cells contain no endogenous essential fatty acids, we were able to create essential fatty acid-repleted cells for which the specific activity of the newly constructed endogenous essential fatty acid pool was known. Loading the endogenous pool with the essential fatty acids arachidonate, eicosapentaenoate, or linoleate (15-20 nmol of fatty acid incorporated/10(6) cells) decreased the uptake of a pulse of arachidonate from 200 to 100 pmol/10(6) cells but had no effect on palmitate uptake. The percent of arachidonate incorporated during the pulse which was released upon agonist stimulation increased 2-fold (4-8%) as the endogenous pool of essential fatty acids was increased from 0 to 15-20 nmol/10(6) cells. This 8% release was at least 3-fold greater than the percent release from the various endogenous essential fatty acid pools. In contrast, loading the endogenous pool with the nonessential fatty acids oleate or palmitate to more than 2-3 times their preexisting cellular level had no effect on the uptake of an arachidonate pulse. Like the essential fatty acids, increasing endogenous oleate increased (by 2-fold) the percent release of arachidonate incorporated during the pulse, whereas endogenous palmitate had no effect on subsequent agonist-induced release from this arachidonate pool.

  18. Prolonged Radiant Exposure of the Middle Ear during Transcanal Endoscopic Ear Surgery.

    PubMed

    Shah, Parth V; Kozin, Elliott D; Remenschneider, Aaron K; Dedmon, Matthew M; Nakajima, Hideko Heidi; Cohen, Michael S; Lee, Daniel J

    2015-07-01

    Transcanal endoscopic ear surgery (EES) provides a high-resolution, wide-field view of the middle ear compared with the conventional operating microscope, reducing the need for a postauricular incision or mastoidectomy. Our group has shown in cadaveric human temporal bone studies that radiant energy from the endoscope tip can quickly elevate temperatures of the tympanic cavity. Elevated temperatures of the middle ear are associated with acute auditory brainstem response shifts in animal models. In EES, proposed methods to decrease middle ear temperature include frequent removal of the endoscope and the use of suction to rapidly dissipate heat; however, the routine application of such cooling techniques remains unknown. Herein, we aim to quantify the duration that the tympanic cavity is typically exposed to the endoscope during routine endoscopic middle ear surgery. We find that the tympanic cavity is exposed to the endoscope without a cooling mechanism for a prolonged period of time. PMID:25779471

  19. Passive and active middle ear implants

    PubMed Central

    Beutner, Dirk; Httenbrink, Karl-Bernd

    2011-01-01

    Besides eradication of chronic middle ear disease, the reconstruction of the sound conduction apparatus is a major goal of modern ear microsurgery. The material of choice in cases of partial ossicular replacement prosthesis is the autogenous ossicle. In the event of more extensive destruction of the ossicular chain diverse alloplastic materials, e.g. metals, ceramics, plastics or composits are used for total reconstruction. Their specialised role in conducting sound energy within a half-open implant bed sets high demands on the biocompatibility as well as the acoustic-mechanic properties of the prosthesis. Recently, sophisticated titanium middle ear implants allowing individual adaptation to anatomical variations are widely used for this procedure. However, despite modern developments, hearing restoration with passive implants often faces its limitations due to tubal-middle-ear dysfunction. Here, implantable hearing aids, successfully used in cases of sensorineural hearing loss, offer a promising alternative. This article reviews the actual state of affairs of passive and active middle ear implants. PMID:22073102

  20. Extracellular Melanin in Inflammatory Middle Ear Disease

    PubMed Central

    Fritz, Mark; Roehm, Pamela C.; Bannan, Michael A.; Lalwani, Anil K.

    2015-01-01

    Objective Melanin is a pigmented polymer with a known role in dermal solar protection. In vertebrates, melanogenesis has been reported in leukocyte population suggesting a potential role in innate immunity. In this study, we report the novel finding of melanin associated with chronic inflammation and speculate on its potential role in the middle ear and mastoid. Study Design Retrospective review of case series Methods Medical records of 6 patients who demonstrated melanin in the ear were reviewed. Results Six patients, ages from 1 to 63 were identified with extracellular melanin within middle ear and/or mastoid air cells at time of surgery. Intraoperative findings included cholesteatoma (n=3), chronic suppurative OM (n=2), and coalescent mastoiditis (n=1). Histologically, extracellular melanin was identified by Fontana-Masson stain; absence of melanocytes was confirmed by the absence of Melan-A and Prussian Blue stain. One patient had a positive stain for CD163 (a marker for macrophages). Conclusion This case series is the first demonstration of extracellular melanin within middle ear mucosa not associated with melanocytes or metastatic melanocytic lesions. The presence of melanin is either a variant of normal anatomy, a pathway of cholesteatoma formation, or a marker of the inflammatory immune response. Melanin's presence in the setting of inflammation suggests that there may be a heretofore unreported link between the pigmentary and immune systems in the ear. PMID:24999501

  1. Evolution and development of the vertebrate ear

    NASA Technical Reports Server (NTRS)

    Fritzsch, B.; Beisel, K. W.

    2001-01-01

    This review outlines major aspects of development and evolution of the ear, specifically addressing issues of cell fate commitment and the emerging molecular governance of these decisions. Available data support the notion of homology of subsets of mechanosensors across phyla (proprioreceptive mechanosensory neurons in insects, hair cells in vertebrates). It is argued that this conservation is primarily related to the specific transducing environment needed to achieve mechanosensation. Achieving this requires highly conserved transcription factors that regulate the expression of the relevant structural genes for mechanosensory transduction. While conserved at the level of some cell fate assignment genes (atonal and its mammalian homologue), the ear has also radically reorganized its development by implementing genes used for cell fate assignment in other parts of the developing nervous systems (e.g., neurogenin 1) and by evolving novel sets of genes specifically associated with the novel formation of sensory neurons that contact hair cells (neurotrophins and their receptors). Numerous genes have been identified that regulate morphogenesis, but there is only one common feature that emerges at the moment: the ear appears to have co-opted genes from a large variety of other parts of the developing body (forebrain, limbs, kidneys) and establishes, in combination with existing transcription factors, an environment in which those genes govern novel, ear-related morphogenetic aspects. The ear thus represents a unique mix of highly conserved developmental elements combined with co-opted and newly evolved developmental elements.

  2. Assessment of Ear Disorders Using Power Reflectance

    PubMed Central

    Nakajima, Hideko Heidi; Rosowski, John J.; Shahnaz, Navid; Voss, Susan E.

    2013-01-01

    This paper describes the effect of various pathologies on power reflectance (PR) and absorbance measured in human adults. The pathologies studied include those affecting the tympanic membrane, the middle-ear ossicles, the middle-ear cavity, the inner ear, and intracranial pressure. Interesting pathology-induced changes in PR that are statistically significant have been reported. Nevertheless, because measurements of PR obtained from normal-hearing subjects have large variations and some pathology-induced changes are small, it can be difficult to use PR alone for differential diagnosis. There are, however, common clinical situations without reliable diagnostic methods that can benefit from PR measurements. These conditions include ears with a normal-appearing tympanic membrane, aerated middle-ear cavity and unknown etiology of conductive hearing loss. PR measurements in conjunction with audiometric measurements of air-bone gap have promise in differentiating among stapes fixation, ossicular discontinuity and superior semicircular canal dehiscence. Another possible application is to monitor an individual for possible changes in intracranial pressure. Descriptions of mechanisms affecting PR change and utilization of PR measurements in clinical scenarios are presented. PMID:23900180

  3. Sciaenid inner ears: a study in diversity.

    PubMed

    Ramcharitar, J; Higgs, D M; Popper, A N

    2001-01-01

    Sciaenid fishes (Family Sciaenidae) could potentially serve as models for understanding the relationship between structure and function in the teleost auditory system, as they show a broad range of variation in not only the structure of the ear but also in the relationship between the ear and swim bladder. In this study, scanning electron microscopy (SEM) was used to investigate inner ear ultrastructure of the Atlantic croaker (Micropogonias undulatus), spotted seatrout (Cynoscion nebulosus), kingfish (Menticirrhus americanus) and spot (Leiostomus xanthurus). These species reflect the diversity of otolith and swim bladder morphology in sciaenids. The distribution of different hair cell bundle types, as well as hair cell orientation patterns on the saccular and lagenar maculae of these fishes were similar to one another. The rostral ends of the saccular sensory epithelia (maculae) were highly expanded in a dorsal-ventral direction in the Atlantic croaker and spotted seatrout as compared to the kingfish and spot. Also, ciliary bundles of the saccular maculae contained more stereocilia in the Atlantic croaker and spotted seatrout as compared with kingfish and spot. The shapes of the lagenar maculae were similar in all four species. In the Atlantic croaker and spotted seatrout lagenar maculae, the number of stereocilia per bundle was greater than those for the kingfish and spot. Given that saccular macula shape and numbers of stereocilia per bundle correlate with swim bladder proximity to the ear in the studied species, it is possible that inner ear ultrastructure could be indicative of auditory ability in fishes. PMID:11910172

  4. Ear Acupuncture in European Traditional Medicine

    PubMed Central

    Firenzuoli, Fabio

    2007-01-01

    Auricular acupuncture is a diagnostic and treatment system based on normalizing the body's dysfunction through stimulation of definite points on the ear. Rudimentary forms of acupuncture which probably arose during the Stone Age have survived in many parts of the world right down to present day. It was used in the ancient Egypt, Rome, Greece and all the Mediterranean area. It is a microacupuncture technique similar to reflexology, and was first described in France in 1950 by Paul Nogier who is considered the Father of modern ear acupuncture. It was speculated that the technique works because groups of pluripotent cells contain information from the whole organism and create regional organization centers representing different parts of the body. Nevertheless stimulation of a reflex point in the ear seems relieve symptoms of distant pathologies. Modern research is confirming the efficacy of ear acupuncture for analgesia and anxiety related disease, while tobacco dependence and other substance abuse still need confirmation. Actually main methodological problems with auricular acupuncture are that exist too many maps with little agreement regarding point location in the ear, and that the correspondence or reflex systems does not correlated with modern knowledge of anatomy and physiology. PMID:18227925

  5. Precise individualized armature for ear reconstruction

    NASA Astrophysics Data System (ADS)

    Evenhouse, Raymond J.; Chen, Xiaoming

    1991-04-01

    The cosmetic result of an ear restored surgically or via prosthetics is dependent on the surgeon''s ability to carve a precise cartilage armature at the time of surgery or the prosthetist''s ability to sculpt in wax an exact duplicate of the patient''s " missing" ear. Introducing CAD/CAM technology into the process benefits the esthetic outcome of these procedures. By utilizing serial section information derived from CAT MRI or moulage techniques a mirrorimage of the patient''s " donor" ear is generated. The resulting earform data is then used for the design of a cartilage armature produced by multi-axis milling or to produce by stereolithography a model which serves as the basis for a prosthesis.

  6. Microsurgical reattachment of totally amputated ears.

    PubMed

    Mutimer, K L; Banis, J C; Upton, J

    1987-04-01

    At a time when microsurgical reattachment of amputated limbs is commonplace, successful reattachment of total ear amputations is rare. Avulsed vessels, small diameters (0.3 to 0.7 mm), and technical difficulties provide primary obstacles. Three clinical cases of ear reattachments are presented which encompass the clinical spectrum of an uncomplicated success, a salvage of an impending failure, and a late failure due to venous thrombosis. In all cases there was difficulty with identification of vessels, with differentiation of arteries from veins, and in the performance of venous anastomoses. Vein grafts were necessary in two of the three patients. Anticoagulation was essential in alleviating venous thrombosis. Medicinal leeches (Hirudo medicinalis) were used to salvage one case with venous thrombosis. Despite the technical difficulties and long operative times, successful microvascular reattachment of an amputated ear is superior to any other means of reattachment or reconstruction. PMID:3823244

  7. Middle ear gas exchange in isobaric counterdiffusion.

    PubMed

    Dueker, C W; Lambertsen, C J; Rosowski, J J; Saunders, J C

    1979-12-01

    Nitrous oxide entry into the middle ear gas space was studied in cats in relation to anesthesia and the vestibular dysfunction caused by isobaric inert gas counter-diffusion in diving. A catheter implanted in the auditory bulla was used for direct gas sampling and pressure measurements. Experiments were designed to evaluate the participation of the eustachian tube, mucosal blood vessels, and tympanic membrane in middle ear gas exchange. The eustachian tube did not contribute to N2O entry and the mucosal blood supply only contributed about one-third of the total N2O accumulation. Diffusion across the tympanic membrane accounted for most of the N2O entering the middle ear from ambient and respiratory environments containing N2O. PMID:536296

  8. [Complications Resulting from Taking Ear Impressions].

    PubMed

    Sugiuchi, Tomoko; Kodera, Kazuoki; Zusho, Hiroyuki; Asano, Yoshikazu; Kanesada, Keiko; Hayashida, Mitsuhiro; Kanaya, Koichiro; Tokumaru, Takeshi

    2015-08-01

    In 2012, we carried out a study in a large sample to understand the secondary injuries caused during the taking ear impressions for hearing aids. This study is a follow-up of previous research conducted in 1986 (285 medical institutions) and 1999 (98 medical institutions). We posted a questionnaire survey to the otolaryngology departments of 3,257 medical institutions. The response rate to the questionnaire was 62.9% (2,050 of the 3,257 institutions), and the results indicated that 301 of the 2050 institutions (14.7%) had experience with secondary injuries, with a total of 460 cases reported. In 342 of the 460 cases (74.3%), the secondary injuries occurred at hearing-aid dealerships, followed by 67 cases (14.6%) at affiliated medical institutions, and 51 cases (11.1%) in other locations, including other medical institutions, rehabilitation counseling centers, and educational institutions. The most common type of secondary injury (298 cases, 64.8%) was caused by the presence of foreign bodies in the ear, which in turn was a result of complications occurring during the removal of residual ear impression material. Of these 298 cases, 32 required excision of the foreign bodies and surgical intervention under general anesthesia. The remaining 10 cases exhibited isolated tympanic membrane perforation without foreign body-related complications. Furthermore, 146 cases (31.7%) developed bleeding and otitis externa following removal of the ear impression, and there were reports of cases with bleeding that required long-term outpatient care and treatment. Therefore, since retention of a foreign body in the ear and tympanic membrane perforation can occur even in patients without a history of surgery or prior otologic history, adjustment of hearing aids requires prior otorhinolaryngological examination. Furthermore, because of the risk of secondary injury when taking ear impressions, this procedure must be performed with caution under the guidance of an otolaryngologist. PMID:26548100

  9. MICROARRAY ANALYSIS OF DICHLOROACETIC ACID-INDUCED CHANGES IN GENE EXPRESSION

    EPA Science Inventory


    MICROARRAY ANALYSIS OF DICHLOROACETIC ACID-INDUCED CHANGES IN GENE EXPRESSION

    Dichloroacetic acid (DCA) is a major by-product of water disinfection by chlorination. Several studies have demonstrated the hepatocarcinogenicity of DCA in rodents when administered in dri...

  10. Dysmorphism of the middle ear: case report

    PubMed Central

    Solero, P; Ferrara, M; Musto, R; Pira, A; Di Lisi, D

    2005-01-01

    Summary Although there are numerous publications in the literature describing the wide range of diagnosis, classifications and treatment of malformations of the hearing apparatus, even more variations can be found in clinical practice. Indeed, each individual case is unique as far as concerns pathogenesis, clinical course and treatment. The case reported herein describes a 12-year-old boy affected by cranio-facial dysmorphism and monolateral conductive hearing loss in the right ear: followed from radiological diagnosis carried out to study a malformation of the ear pinna to surgical treatment. PMID:16602328

  11. High intensity anthropogenic sound damages fish ears

    NASA Astrophysics Data System (ADS)

    McCauley, Robert D.; Fewtrell, Jane; Popper, Arthur N.

    2003-01-01

    Marine petroleum exploration involves the repetitive use of high-energy noise sources, air-guns, that produce a short, sharp, low-frequency sound. Despite reports of behavioral responses of fishes and marine mammals to such noise, it is not known whether exposure to air-guns has the potential to damage the ears of aquatic vertebrates. It is shown here that the ears of fish exposed to an operating air-gun sustained extensive damage to their sensory epithelia that was apparent as ablated hair cells. The damage was regionally severe, with no evidence of repair or replacement of damaged sensory cells up to 58 days after air-gun exposure.

  12. Middle ear cholesteatoma in 11 dogs

    PubMed Central

    Greci, Valentina; Travetti, Olga; Di Giancamillo, Mauro; Lombardo, Rocco; Giudice, Chiara; Banco, Barbara; Mortellaro, Carlo M.

    2011-01-01

    Middle ear cholesteatoma is a rare condition in dogs with chronic otitis. Otorrhea, otodinia, and pain on temporomandibular joint palpation are the most common clinical signs. Neurological abnormalities are often detectable. Computed tomography reveals the presence of an expansive and invasive unvascularized lesion involving the tympanic cavity and the bulla, with little or no contrast enhancement after administration of contrast mediu. Video-otoscopy may detect pearly growth or white/yellowish scales in the middle ear cavity. Surgery is the only therapy but is associated with a high risk of recurrence. PMID:22131579

  13. Growth hormone releasing factor (GRF) increases free arachidonate levels in the pituitary: a role for lipoxygenase products

    SciTech Connect

    Canonico, P.L.; Speciale, C.; Sortino, M.A.; Cronin, M.J.; MacLeod, R.M.; Scapagnini, U.

    1986-01-20

    GRF, a specific stimulator of GH release, increased in a concentration- and time-dependent manner pituitary (/sup 3/H)-arachidonate levels in vitro. This effect was antagonized by 100 nM somatostatin. Exogenous arachidonate also stimulated GH release in vitro. Quinacrine, a phospholipase A2 inhibitor, reduced both basal and GRF-stimulated free arachidonate levels as well as GH release. The cyclooxygenase inhibitor indomethacin was ineffective, while BW755c, which also inhibits the lipoxygenase pathway, produced a further increase in the levels of the fatty acid stimulated by GRF and potently reduced GH release. These results provide additional evidence for the involvement of arachidonate metabolism in the hormone-releasing effect of GRF at the somatotroph. 14 references, 1 figure, 2 tables.

  14. Melanocyte-stimulating properties of arachidonic acid metabolites: possible role in postinflammatory pigmentation.

    PubMed

    Tomita, Y; Maeda, K; Tagami, H

    1992-11-01

    Normal human epidermal melanocytes became swollen and more dendritic with an increase in the amount of tyrosinase and immunoreactive b-locus protein when they were cultured for 2 days with the following arachidonic acid metabolites: prostaglandin (PG) D2, leukotriene (LT) B4, LTC4, LTD4, LTE4, thromboxane (TX) B2 and 12-hydroxy eicosatetraenoic acid (12-HETE). The effect of LTC4 was particularly strong compared to that of PGE2, about which we have previously reported. On the other hand, PGE1, PGF2 alpha and 6-ketoPGF1 alpha did not show any significant stimulatory effect. These data suggest that arachidonate-derived chemical mediators, especially LTC4, may be responsible for the induction of post-inflammatory hyperpigmentation of the skin. PMID:1292020

  15. Expression analysis for genes involved in arachidonic acid biosynthesis in Mortierella alpina CBS 754.68

    PubMed Central

    Samadlouie, Hamid-Reza; Hamidi-Esfahani, Zohreh; Alavi, Seyed-Mehdi; Varastegani, Boshra

    2014-01-01

    The time courses for production of fungal biomass, lipid, phenolic and arachidonic acid (ARA) as well as expression of the genes involved in biosynthesis of ARA and lipid were examined in Mortierella alpina CBS 754.68. A significant increase in the arachidonic acid content in lipids that coincided with reduced levels of lipid was obtained. Reduced gene expression occurred presumably due to the steady reduction of carbon and nitrogen resources. However, these energy resources were inefficiently compensated by the breakdown of the accumulated lipids that in turn, induced up-regulated expression of the candidate genes. The results further indicated that the expression of the GLELO encoding gene is a rate-limiting step in the biosynthesis of ARA in the early growth phase. PMID:25242926

  16. Molecular Dynamics Simulations of Arachidonic Acid Complexes with COX-1 and COX-2

    PubMed Central

    Furse, Kristina E.; Pratt, Derek A.; Porter, Ned A.; Lybrand, Terry P.

    2008-01-01

    The cyclooxygenase (COX) enzymes are responsible for the committed step in prostaglandin biosynthesis, the generation of prostaglandin H2. As a result, these enzymes are pharmacologically important targets for non-steroidal anti-inflammatory drugs, such as aspirin and newer COX-2 selective inhibitors. The cyclooxygenases are functional homodimers, and each subunit contains both a cyclooxygenase and a peroxidase active site. These enzymes are quite interesting mechanistically, as the conversion of arachidonic acid to prostaglandin H2 requires two oxygenation and two cyclization reactions, resulting in the formation of five new chiral centers with nearly absolute regio- and stereochemical fidelity. We have used molecular dynamics (MD) simulations to investigate the equilibrium behavior of both COX-1 and COX-2 enzyme isoforms with bound arachidonate. These simulations were compared with reference simulations of arachidonate in solution to explore the effect of enzyme on substrate conformation and positioning in the active site. The simulations suggest that the substrate has greater conformational freedom in the COX-2 active site, consistent with the larger COX-2 active site volume observed in X-ray crystal structures. The simulations reveal different conformational behavior for arachidonate in each subunit over the course of extended equilibrium MD simulations. The simulations also provide detailed information for several protein channels that might be important for oxygen and water transport to or from active sites, or for intermediate trafficking between the cyclooxygenase and peroxidase active sites. The detailed comparisons for COX-1 versus COX-2 active site structural fluctuations may also provide useful information for design of new isozyme-selective inhibitors. PMID:16519514

  17. Differential stimulation of luminol-enhanced chemiluminescence (CL) and arachidonic acid metabolism in rat peritoneal neutrophils

    SciTech Connect

    Sturm, R.J.; Adams, L.M.; Cullinan, C.A.; Berkenkopf, J.W.; Weichman, B.M.

    1986-03-05

    Phorbol 12-myristate, 13-acetate (PMA) induced the production of radical oxygen species (ROS) from rat peritoneal neutrophils as assessed by CL. ROS generation occurred in a time- (maximum at 13.5 min) and dose- (concentration range of 1.7-498 nM) related fashion. However, 166 nM PMA did not induce either cyclooxygenase (CO) or lipoxygenase (LPO) product formation by 20 min post-stimulation. Conversely, A23187, at concentrations between 0.1 and 10 ..mu..M, stimulated both pathways of arachidonic acid metabolism, but had little or no effect upon ROS production. When suboptimal concentrations of PMA (5.5 nM) and A23187 (0.1-1 ..mu..M) were coincubated with the neutrophils, a synergistic ROS response was elicited. However, arachidonic acid metabolism in the presence of PMA was unchanged relative to A12187 alone. Nordihydroguaiaretic acid (NDGA) inhibited both PMA-induced CL (IC/sub 50/ = 0.9 ..mu..M) and A23187-induced arachidonic acid metabolism (IC/sub 50/ = 1.7 ..mu..M and 6.0 ..mu..M for LPO and CO, respectively). The mixed LPO-CO inhibitor, BW755C, behaved in a qualitatively similar manner to NDGA, whereas the CO inhibitors, indomethacin, piroxicam and naproxen had no inhibitory effect on ROS generation at concentrations as high as 100 ..mu..M. These results suggest that NDGA and BW755C may inhibit CL and arachidonic acid metabolism by distinct mechanisms in rat neutrophils.

  18. Lipoxygenase-mediated pro-radical effect of melatonin via stimulation of arachidonic acid metabolism

    SciTech Connect

    Radogna, F.; Sestili, P.; Martinelli, C.; Paolillo, M.; Paternoster, L.; Albertini, M.C.; Accorsi, A.; Gualandi, G.; Ghibelli, L.

    2009-07-15

    We have shown that melatonin immediately and transiently stimulates intracellular free radical production on a set of leukocytes, possibly as a consequence of calmodulin binding. We show here that melatonin-induced ROS are produced by lipoxygenase (LOX), since they are prevented by a set of LOX inhibitors, and are accompanied by increase of the 5-LOX product 5-HETE. LOX activation is accompanied by strong liberation of AA; inhibition of Ca{sup 2+}-independent, but not Ca{sup 2+}-dependent, phospholipase A2 (PLA2), prevents both melatonin-induced arachidonic acid and ROS production, whereas LOX inhibition only prevents ROS, indicating that PLA2 is upstream with respect to LOX, as occurs in many signaling pathways. Chlorpromazine, an inhibitor of melatonin-calmodulin interaction, inhibits both ROS and arachidonic acid production, thus possibly placing calmodulin at the origin of a melatonin-induced pro-radical pathway. Interestingly, it is known that Ca{sup 2+}-independent PLA2 binds to calmodulin: our results are compatible with PLA2 being liberated by melatonin from a steady-state calmodulin sequestration, thus initiating an arachidonate signal transduction. These results delineate a novel molecular pathway through which melatonin may participate to the inflammatory response.

  19. Targeted Chiral Analysis of Bioactive Arachidonic Acid Metabolites Using Liquid-Chromatography-Mass Spectrometry

    PubMed Central

    Mesaros, Clementina; Blair, Ian A.

    2012-01-01

    A complex structurally diverse series of eicosanoids arises from the metabolism of arachidonic acid. The metabolic profile is further complicated by the enantioselectivity of eicosanoid formation and the variety of regioisomers that arise. In order to investigate the metabolism of arachidonic acid in vitro or in vivo, targeted methods are advantageous in order to distinguish between the complex isomeric mixtures that can arise by different metabolic pathways. Over the last several years this targeted approach has become more popular, although there are still relatively few examples where chiral targeted approaches have been employed to directly analyze complex enantiomeric mixtures. To efficiently conduct targeted eicosanoid analyses, LC separations are coupled with collision induced dissociation (CID) and tandem mass spectrometry (MS/MS). Product ion profiles are often diagnostic for particular regioisomers. The highest sensitivity that can be achieved involves the use of selected reaction monitoring/mass spectrometry (SRM/MS); whereas the highest specificity is obtained with an SRM transitions between an intense parent ion, which contains the intact molecule (M) and a structurally significant product ion. This review article provides an overview of arachidonic acid metabolism and targeted chiral methods that have been utilized for the analysis of the structurally diverse eicosanoids that arise. PMID:24957514

  20. Glucose increases the synthesis of lipoxygenase-mediated metabolites of arachidonic acid in intact rat islets.

    PubMed Central

    Metz, S A

    1985-01-01

    Previous studies suggested that products of a 12-lipoxygenase pathway in the pancreatic islet may promote insulin release. To determine whether glucose augments the production of such metabolites, intact rat islets prelabeled with [3H]arachidonate were stimulated with glucose, and 12-hydroxy-5,8,10,14-icosatetraenoic acid (12-HETE) release was measured by using HPLC. D-Glucose (16.7 mM) augmented the enzymatic synthesis of 12-HETE by 271% above that seen with 0-1.7 mM glucose. The glucose effect was stereospecific and preferential for the alpha anomer; it was modestly potentiated by the cyclo-oxygenase inhibitor ibuprofen. Glucose-stimulated 12-HETE accumulation was abrogated by mannoheptulose and was reproduced by the trioses glyceraldehyde or dihydroxyacetone, suggesting that the metabolism of glucose to glucose 6-phosphate or triose phosphates (or both) is critical. Glucose also augmented [3H]arachidonate labeling of islets, suggesting an action at the level of substrate release or re-uptake (or both). These features of islet 12-HETE synthesis accord well with other known effects of glucose on beta cell function and suggest that lipoxygenase-mediated metabolites of arachidonate may be suitable candidates to mediate or amplify glucose's effects on insulin release. PMID:3918302

  1. Arachidonic acid metabolites in antrochoanal polyp and nasal polyp associated with chronic paranasal sinusitis.

    PubMed

    Jang, Y J; Rhee, C K; Oh, C H; Ryoo, H G; Kim, H G; Ha, M

    2000-06-01

    The aim of this study was to investigate the role of arachidonic acid metabolites (AAMs) in the pathogenesis of antrochoanal polyp (ACP). Using high-performance liquid chromatography (HPLC), we assayed the tissue concentrations of 6-keto-PGF1alpha, leukotrienes (LTs) and hydroxyeicosatetraenoic acids (HETE). Concentrations of AAMs in ACP were compared with the level in the control turbinate tissues and nasal polyps associated with chronic paranasal sinusitis (NPS). The concentrations of 6-keto-PGF1alpha were not significantly different in the control turbinate, ACP and NPS groups. In ACP, concentrations of LTC4, 15-HETE and 12-HETE were significantly lower than in the control turbinate. The striking differences in the profile of AAMs between ACP and NPS included a lack of production of LTD4 and LTE4 in ACP, also detectable in NPS, and markedly lower concentrations of 15-HETE and 12-HETE in ACP. The results of this study indicate that decreased lipoxygenase pathway products in arachidonic acid metabolism may be involved in the pathogenesis of ACP. However, in the pathogenesis of NPS, increased production of LTD4 and LTE4 may have an important role. Taken together, our results demonstrate a difference in pathogenesis between ACP and NPS, particularly in terms of arachidonic acid metabolism. PMID:10958407

  2. Get Smart: Know When Antibiotics Work - Ear Infections

    MedlinePLUS

    ... on the Farm Get Smart About Antibiotics Week Ear Infection Language: English Español (Spanish) Recommend on Facebook ... Antibiotics are not recommended to help treat many ear infections. Your healthcare professional will be able to ...

  3. Middle Ear Infection (Chronic Otitis Media) and Hearing Loss

    MedlinePLUS

    ... Doctor Near You Middle Ear Infection (Chronic Otitis Media) and Hearing Loss Middle Ear Infection (Chronic Otitis ... staff at newsroom@entnet.org . What is otitis media? Otitis media refers to inflammation of the middle ...

  4. "Hot Tub Rash" and "Swimmer's Ear" (Pseudomonas)

    MedlinePLUS

    Facts About “Hot Tub Rash” and “Swimmer’s Ear” (Pseudomonas) What is Pseudomonas and how can it affect me? Pseudomonas (sue-doh- ... a major cause of infections commonly known as “hot tub rash” and “swimmer’s ear.” This germ is ...

  5. Mule Ear Drapery in Jewel Cave

    USGS Multimedia Gallery

    Jewel Cave is currently the 3rd most extensive cave network in the world. It is believed to have formed completely underwater, thus leading to the extensive coating of calcite crystals. In the center of this image, a cave formation known as mule-ear drapery can be seen....

  6. Getting Teens to Read with Their Ears

    ERIC Educational Resources Information Center

    Fues, Marianne Cole

    2009-01-01

    Audiobooks have been around for years in various formats, like cassette tapes and CDs. This article describes a new type of audiobook on the market which is generating an interest in "reading." The device, called Playaway, is the size of a MP3 player and comes with a lanyard and ear buds. Buttons on the back of the player control the speed and…

  7. Ear biometric recognition using local texture descriptors

    NASA Astrophysics Data System (ADS)

    Benzaoui, Amir; Hadid, Abdenour; Boukrouche, Abdelhani

    2014-09-01

    Automated personal identification using the shape of the human ear is emerging as an appealing modality in biometric and forensic domains. This is mainly due to the fact that the ear pattern can provide rich and stable information to differentiate and recognize people. In the literature, there are many approaches and descriptors that achieve relatively good results in constrained environments. The recognition performance tends, however, to significantly decrease under illumination variation, pose variation, and partial occlusion. In this work, we investigate the use of local texture descriptors, namely local binary patterns, local phase quantization, and binarized statistical image features for robust human identification from two-dimensional ear imaging. In contrast to global image descriptors which compute features directly from the entire image, local descriptors representing the features in small local image patches have proven to be more effective in real-world conditions. Our extensive experimental results on the benchmarks IIT Delhi-1, IIT Delhi-2, and USTB ear databases show that local texture features in general and BSIF in particular provide a significant performance improvement compared to the state-of-the-art.

  8. Ear Infections - Multiple Languages: MedlinePlus

    MedlinePLUS

    ... List of All Topics All Ear Infections - Multiple Languages To use the sharing features on this page, please enable JavaScript. French (français) Japanese (日本語) Korean (한국어) Russian (Русский) Somali ( ...

  9. Keep Your Ear-Lids Open.

    ERIC Educational Resources Information Center

    Ferrington, Gary

    1994-01-01

    This article suggests that the development of listening skills should extend to the "soundscape" of nonspeech acoustical information. It presents a model for effective aural processing, identifies categories of information obtained from nonverbal sound, and explores "ear-tuning" or listening exercises that use sound to glean information about

  10. Getting Teens to Read with Their Ears

    ERIC Educational Resources Information Center

    Fues, Marianne Cole

    2009-01-01

    Audiobooks have been around for years in various formats, like cassette tapes and CDs. This article describes a new type of audiobook on the market which is generating an interest in "reading." The device, called Playaway, is the size of a MP3 player and comes with a lanyard and ear buds. Buttons on the back of the player control the speed and

  11. Diving injuries to the inner ear.

    PubMed

    Farmer, J C

    1977-01-01

    Most of the previous literature concerning otologic problems in compressed gas environments has emphasized middle ear barotrauma. With recent increases in commercial, military, and sport diving to deeper depths, inner ear disturbances during these exposures have been noted more frequently. Studies of inner ear physiology and pathology during diving indicate that the causes and treatment of these problems differ depending upon the phase and type of diving. Humans exposed to simulated depths of up to 305 meters without barotrauma or decompression sickness develop transient, conductive hearing losses with no audiometric evidence of cochlear dysfunction. Transient vertigo and nystagmus during diving have been noted with caloric stimulation, resulting from the unequal entry of cold water into the external auditory canals, and with asymmetric middle ear pressure equilibration during ascent and descent (alternobaric vertigo). Equilibrium disturbances noted with nitrogen narcosis, oxygen toxicity, hypercarbia, or hypoxia appear primarily related to the effects of these conditions upon the central nervous system and not to specific vestibular end-organ dysfunction. Compression of humans in helium-oxygen at depths greater than 152.4 meters results in transient symptoms of tremor, dizziness, and nausea plus decrements in postural equilibrium and psychomotor performance, the high pressure nervous syndrome. Vestibular function studies during these conditions indicate that these problems are due to central dysfunction and not to vestibular end-organ dysfunction. Persistent inner ear injuries have been noted during several phases of diving: 1) Such injuries during compression (inner ear barotrauma) have been related to round window ruptures occurring with straining, or a Valsalva's maneuver during inadequate middle ear pressure equilibration. Divers who develop cochlear and/or vestibular symptoms during shallow diving in which decompression sickness is unlikely or during compression in deeper diving, should be placed on bed rest with head elevation and avoidance of maneuvers which result in increased cerebrospinal fluid and intralabyrinthine pressure. With no improvement in symptoms after 48 hours, exploratory tympanotomy and repair of a possible labyrinthine window fistula should be considered. Recompression therapy is contraindicated in these cases... PMID:402882

  12. Percentages of oleic acid and arachidonic acid are inversely related in phospholipids of human sera

    PubMed Central

    2013-01-01

    Background Many health effects of oils rich in oleic acid (18:1 n9) seem to be opposite those of arachidonic acid (20:4 n6), i.e. concerning cardiovascular risk. In recent study in rats we observed that percentages of oleic acid and arachidonic acid were inversely related in total serum lipids. In the present work we investigate whether an inverse relationship between this couple of fatty acids also exists in the phospholipid fraction of human sera. Methods The study group consisted of 11 men and 35 women. Mean age was 23.8 ± 2.5 years (mean ± SD), and the body mass index was 23.5 ± 3.2 kg/m2. After fasting overnight, blood was drawn and the concentration of fatty acids in serum phospholipids was determined, using gas chromatography. We studied the association between percentages of oleic acid and arachidonic acid using bivariate correlations (Pearson), and multiple linear regressions. Results We found an inverse relationship (r = −0.563, p < 0.001; n = 46) between % oleic acid and % arachidonic acid in the serum phosholipid fraction of the 46 fasting subjects. By multiple linear regression, and % 20:4 n6 as the dependent variable, the inverse association with % 18:1 n9 persisted when controlling for sex, age, body mass index, and percentages of the other fatty acids measured (t = −17.6, p < 0.001). Per cent 20:4 n6 seemed to correlate negatively (r = −0.289, p = 0.05) with the (18:1 n9)/(18:0) ratio, estimating Delta9 desaturase activity, and % oleic acid correlated negatively (r = −0.321, p = 0.029) with the (20:4)/(18:2) ratio, estimating desaturases/elongase activities. Conclusions In a group of healthy human subjects, percentages of oleic acid and arachidonic acid were inversely related, and the inverse association persisted when controlling for possible confounding variables. The findings might contribute to explain positive health effects of foods rich in oleic acid. PMID:23870138

  13. 40 CFR 211.206-1 - Real ear method.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation...

  14. 15 CFR 734.2 - Important EAR terms and principles.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 2 2011-01-01 2011-01-01 false Important EAR terms and principles... OF THE EXPORT ADMINISTRATION REGULATIONS § 734.2 Important EAR terms and principles. (a) Subject to the EAR—Definition. (1) “Subject to the EAR” is a term used in the EAR to describe those items...

  15. 14 CFR 67.105 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Ear, nose, throat, and equilibrium. 67.105... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION First-Class Airman Medical Certificate § 67.105 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a first-class...

  16. 15 CFR 734.2 - Important EAR terms and principles.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 2 2014-01-01 2014-01-01 false Important EAR terms and principles... OF THE EXPORT ADMINISTRATION REGULATIONS § 734.2 Important EAR terms and principles. (a) Subject to the EAR—Definition. (1) “Subject to the EAR” is a term used in the EAR to describe those items...

  17. 14 CFR 67.205 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Ear, nose, throat, and equilibrium. 67.205... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Second-Class Airman Medical Certificate § 67.205 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a second-class...

  18. 14 CFR 67.305 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Ear, nose, throat, and equilibrium. 67.305... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Third-Class Airman Medical Certificate § 67.305 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a third-class...

  19. 14 CFR 67.205 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Ear, nose, throat, and equilibrium. 67.205... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Second-Class Airman Medical Certificate § 67.205 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a second-class...

  20. 14 CFR 67.105 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Ear, nose, throat, and equilibrium. 67.105... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION First-Class Airman Medical Certificate § 67.105 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a first-class...

  1. 14 CFR 67.205 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Ear, nose, throat, and equilibrium. 67.205... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Second-Class Airman Medical Certificate § 67.205 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a second-class...

  2. 40 CFR 211.206-1 - Real ear method.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation...

  3. 14 CFR 67.305 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Ear, nose, throat, and equilibrium. 67.305... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Third-Class Airman Medical Certificate § 67.305 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a third-class...

  4. 40 CFR 211.206-1 - Real ear method.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation...

  5. 40 CFR 211.206-1 - Real ear method.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation...

  6. 14 CFR 67.205 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Ear, nose, throat, and equilibrium. 67.205... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Second-Class Airman Medical Certificate § 67.205 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a second-class...

  7. 40 CFR 211.206-1 - Real ear method.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Real ear method. 211.206-1 Section 211... PRODUCT NOISE LABELING Hearing Protective Devices § 211.206-1 Real ear method. (a) The value of sound... “Method for the Measurement of Real-Ear Protection of Hearing Protectors and Physical Attenuation...

  8. 14 CFR 67.105 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Ear, nose, throat, and equilibrium. 67.105... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION First-Class Airman Medical Certificate § 67.105 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a first-class...

  9. 15 CFR 734.2 - Important EAR terms and principles.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Important EAR terms and principles... OF THE EXPORT ADMINISTRATION REGULATIONS § 734.2 Important EAR terms and principles. (a) Subject to the EAR—Definition. (1) “Subject to the EAR” is a term used in the EAR to describe those items...

  10. 14 CFR 67.305 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Ear, nose, throat, and equilibrium. 67.305... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Third-Class Airman Medical Certificate § 67.305 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a third-class...

  11. 15 CFR 734.2 - Important EAR terms and principles.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 2 2013-01-01 2013-01-01 false Important EAR terms and principles... OF THE EXPORT ADMINISTRATION REGULATIONS § 734.2 Important EAR terms and principles. (a) Subject to the EAR—Definition. (1) “Subject to the EAR” is a term used in the EAR to describe those items...

  12. 15 CFR 734.2 - Important EAR terms and principles.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 2 2012-01-01 2012-01-01 false Important EAR terms and principles... OF THE EXPORT ADMINISTRATION REGULATIONS § 734.2 Important EAR terms and principles. (a) Subject to the EAR—Definition. (1) “Subject to the EAR” is a term used in the EAR to describe those items...

  13. 14 CFR 67.105 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Ear, nose, throat, and equilibrium. 67.105... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION First-Class Airman Medical Certificate § 67.105 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a first-class...

  14. 14 CFR 67.305 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Ear, nose, throat, and equilibrium. 67.305... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Third-Class Airman Medical Certificate § 67.305 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a third-class...

  15. 14 CFR 67.205 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Ear, nose, throat, and equilibrium. 67.205... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Second-Class Airman Medical Certificate § 67.205 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a second-class...

  16. 14 CFR 67.305 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Ear, nose, throat, and equilibrium. 67.305... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION Third-Class Airman Medical Certificate § 67.305 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a third-class...

  17. 14 CFR 67.105 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Ear, nose, throat, and equilibrium. 67.105... (CONTINUED) AIRMEN MEDICAL STANDARDS AND CERTIFICATION First-Class Airman Medical Certificate § 67.105 Ear, nose, throat, and equilibrium. Ear, nose, throat, and equilibrium standards for a first-class...

  18. The development of the mammalian outer and middleear.

    PubMed

    Anthwal, Neal; Thompson, Hannah

    2016-02-01

    The mammalian ear is a complex structure divided into three main parts: the outer; middle; and inner ear. These parts are formed from all three germ layers and neural crest cells, which have to integrate successfully in order to form a fully functioning organ of hearing. Any defect in development of the outer and middle ear leads to conductive hearing loss, while defects in the inner ear can lead to sensorineural hearing loss. This review focuses on the development of the parts of the ear involved with sound transduction into the inner ear, and the parts largely ignored in the world of hearing research: the outer and middle ear. The published data on the embryonic origin, signalling, genetic control, development and timing of the mammalian middle and outer ear are reviewed here along with new data showing the Eustachian tube cartilage is of dual embryonic origin. The embryonic origin of some of these structures has only recently been uncovered (Science, 339, 2013, 1453; Development, 140, 2013, 4386), while the molecular mechanisms controlling the growth, structure and integration of many outer and middle ear components are hardly known. The genetic analysis of outer and middle ear development is rather limited, with a small number of genes often affecting either more than one part of the ear or having only very small effects on development. This review therefore highlights the necessity for further research into the development of outer and middle ear structures, which will be important for the understanding and treatment of conductive hearing loss. PMID:26227955

  19. Ear deformity in children following high ear-piercing: current practice, consent issues and legislation.

    PubMed

    Jervis, P N; Clifton, N J; Woolford, T J

    2001-07-01

    In this presentation we examine the practice of high ear-piercing in children, the issue of informed consent and current legislation. We sampled current practice and consent policy by visiting nine establishments in Sheffield providing this service. There were two high street department stores, two fashion accessory outlets and five body-piercing studios. Enquiries were made as to the technique used, knowledge of complications, customer counselling and consent policy. A photograph of an ear with a cosmetic deformity following high ear-piercing was shown and awareness of this possible outcome was noted. Two ear-piercing techniques were identified, either a spring-loaded gun firing a blunt stud or the use of a body-piercing needle. The fashion accessory outlets were prepared to pierce any part of the ear using a spring-loaded gun in children under 16 years of age. There was a general lack of knowledge about possible serious complications. Two of the body piercers would not perform high ear-piercing on clients under the age of 16 years. The body piercers use a disposable needle and were of the opinion that using a spring-loaded gun shatters the cartilage and increases the risk of infection. The best technique is open to debate and it may be that the perceived unsavoury environment of the body-piercing studio represents a safer option than the more respectable or cheaper alternatives. The practice of body piercing in the UK remains uncontrolled. PMID:11485579

  20. Knowledge, Attitude and Practice of Ear Care in Coastal Karnataka

    PubMed Central

    Ganapathi, Keerthan; Kanthila, Jayashree

    2015-01-01

    Introduction Ear as an organ is necessary for the perception of sound and body balance. Ear infection, diabetes mellitus, hypertension and excessive use of mobile phone for listening to music at high volume all can reduce hearing. No earlier study was available in the costal Karnataka population, regarding the practice of ear care. The study objective was to ascertain the level of knowledge of the community regarding ear care, to find out whether some of the common conditions affecting hearing are known and to find out the common practices involved in maintaining ear hygiene. Materials and Methods This cross-sectional study was conducted on 500 subjects in two tertiary care hospitals by convenient sampling, using self-administered questionnaire. Knowledge, Attitude and Practice across the age groups, religion & education background were studied. Results Across different education groups, 66.7%-90% did not know that cold can cause ear infection and 46.7%-75.0% did not know that diabetes and hypertension can reduce hearing. When there is ear pain or discharge, people put ear drops available at home in 48.3%-75.0% across 3 age groups; 58.5%-61.5% across 3 religions and 44.8%-67.9% across 5 education groups. No statistically significant difference was found in the practice of pouring oil into ears across religions. A total of 58.6%-100% daily clean inside the ear and 70-100% use cotton buds. Conclusion General perception of the people is that ear is necessary only for hearing. Majority did not know that nasal infection can affect the ear and that DM and hypertension can cause hearing loss. When there is ear pain and discharge, most of the adults put drops that are available at home. Pouring oil into the ears and cleaning inside the ear canals is routinely practiced in costal Karnataka. PMID:26816922

  1. Acid-induced exchange of the imino proton in G.C pairs.

    PubMed

    Nonin, S; Leroy, J L; Gueron, M

    1996-02-15

    Acid-induced catalysis of imino proton exchange in G.C pairs of DNA duplexes is surprisingly fast, being nearly as fast as for the isolated nucleoside, despite base-pair dissociation constants in the range of 10(-5) at neutral or basic pH. It is also observed in terminal G.C pairs of duplexes and in base pairs of drug-DNA complexes. We have measured imino proton exchange in deoxyguanosine and in the duplex (ATATAGATCTATAT) as a function of pH. We show that acid-induced exchange can be assigned to proton transfer from N7-protonated guanosine to cytidine in the open state of the pair. This is faster than transfer from neutral guanosine (the process of intrinsic catalysis previously characterized at neutral ph) due to the lower imino proton pK of the protonated form, 7.2 instead of 9.4. Other interpretations are excluded by a study of exchange catalysis by formiate and cytidine as exchange catalysts. The cross-over pH between the regimes of pH-independent and acid-induced exchange rates is more basic in the case of base pairs than in the mononucleoside, suggestive of an increase by one to two decades in the dissociation constant of the base pair upon N7 protonation of G. Acid-induced catalysis is much weaker in A.T base pairs, as expected in view of the low pK for protonation of thymidine. PMID:8604298

  2. Minocycline ameliorates prenatal valproic acid induced autistic behaviour, biochemistry and blood brain barrier impairments in rats.

    PubMed

    Kumar, Hariom; Sharma, Bhupesh

    2016-01-01

    Autism is a neurodevelopment disorder. One percent worldwide population suffers with autism and males suffer more than females. Microglia plays an important role in neurodevelopment, neuropsychiatric and neurodegenerative disorders. The present study has been designed to investigate the role of minocycline in prenatal valproic acid induced autism in rats. Animals with prenatal valproic acid have reduced social interaction (three chamber social behaviour apparatus), spontaneous alteration (Y-Maze), exploratory activity (Hole board test), intestinal motility, serotonin levels (both in prefrontal cortex and ileum) and prefrontal cortex mitochondrial complex activity (complexes I, II, IV). Furthermore, prenatal valproic acid treated animals have shown an increase in locomotion (actophotometer), anxiety (elevated plus maze), brain oxidative stress (thiobarbituric acid reactive species, glutathione, catalase), nitrosative stress (nitrite/nitrate), inflammation (both in brain and ileum myeloperoxidase activity), calcium and blood brain barrier permeability. Treatment with minocycline significantly attenuated prenatal valproic acid induced reduction in social interaction, spontaneous alteration, exploratory activity intestinal motility, serotonin levels and prefrontal cortex mitochondrial complex activity. Furthermore, minocycline has also attenuated prenatal valproic acid induced increase in locomotion, anxiety, brain oxidative and nitrosative stress, inflammation, calcium and blood brain barrier permeability. Thus, it may be concluded that prenatal valproic acid has induced autistic behaviour, biochemistry and blood brain barrier impairment in animals, which were significantly attenuated by minocycline. Minocycline should be explored further for its therapeutic benefits in autism. PMID:26551768

  3. Houttuyniae Herba Attenuates Kainic Acid-Induced Neurotoxicity via Calcium Response Modulation in the Mouse Hippocampus.

    PubMed

    Kim, Hyo Geun; Jeong, Hyun Uk; Hong, Sung In; Oh, Myung Sook

    2015-12-01

    Epilepsy is a complex neurological disorder characterized by the repeated occurrence of electrical activity known as seizures. This activity induces increased intracellular calcium, which ultimately leads to neuronal damage. Houttuyniae Herba, the aerial part of Houttuynia cordata, has various pharmacological effects and is widely used as a traditional herb. In the present study, we evaluated the protective effects of Houttuyniae Herba water extract on kainic acid-induced neurotoxicity. Kainic acid directly acts on calcium release, resulting in seizure behavior, neuronal damage, and cognitive impairment. In a rat primary hippocampal culture system, Houttuyniae Herba water extract significantly protected neuronal cells from kainic acid toxicity. In a seizure model where mice received intracerebellar kainic acid injections, Houttuyniae Herba water extract treatment resulted in a lower seizure stage score, ameliorated cognitive impairment, protected neuronal cells against kainic acid-induced toxicity, and suppressed neuronal degeneration in the hippocampus. In addition, Houttuyniae Herba water extract regulated increases in the intracellular calcium level, its related downstream pathways (reactive oxygen species production and mitochondrial dysfunction), and calcium/calmodulin complex kinase type II immunoreactivity in the mouse hippocampus, which resulted from calcium influx stimulation induced by kainic acid. These results demonstrate the neuroprotective effects of Houttuyniae Herba water extract through inhibition of calcium generation in a kainic acid-induced epileptic model. PMID:26366753

  4. Estimation of outer-middle ear transmission using DPOAEs and fractional-order modeling of human middle ear

    NASA Astrophysics Data System (ADS)

    Naghibolhosseini, Maryam

    Our ability to hear depends primarily on sound waves traveling through the outer and middle ear toward the inner ear. Hence, the characteristics of the outer and middle ear affect sound transmission to/from the inner ear. The role of the middle and outer ear in sound transmission is particularly important for otoacoustic emissions (OAEs), which are sound signals generated in a healthy cochlea, and recorded by a sensitive microphone placed in the ear canal. OAEs are used to evaluate the health and function of the cochlea; however, they are also affected by outer and middle ear characteristics. To better assess cochlear health using OAEs, it is critical to quantify the impact of the outer and middle ear on sound transmission. The reported research introduces a noninvasive approach to estimate outer-middle ear transmission using distortion product otoacoustic emissions (DPOAEs). In addition, the role of the outer and middle ear on sound transmission was investigated by developing a physical/mathematical model, which employed fractional-order lumped elements to include the viscoelastic characteristics of biological tissues. Impedance estimations from wideband refectance measurements were used for parameter fitting of the model. The model was validated comparing its estimates of the outer-middle ear sound transmission with those given by DPOAEs. The outer-middle ear transmission by the model was defined as the sum of forward and reverse outer-middle ear transmissions. To estimate the reverse transmission by the model, the probe-microphone impedance was calculated through estimating the Thevenin-equivalent circuit of the probe-microphone. The Thevenin-equivalent circuit was calculated using measurements in a number of test cavities. Such modeling enhances our understanding of the roles of different parts of the outer and middle ear and how they work together to determine their function. In addition, the model would be potentially helpful in diagnosing pathologies of cochlear or middle ear origin.

  5. Structures that Contribute to Middle-Ear Admittance in Chinchilla

    PubMed Central

    Rosowski, John J.; Ravicz, Michael E.; Songer, Jocelyn E.

    2009-01-01

    We describe measurements of middle-ear input admittance in chinchillas (Chinchilla lanigera) before and after various manipulations that define the contributions of different middle-ear components to function. The chinchillas middle-ear air spaces have a large effect on the low-frequency compliance of the middle ear, and removing the influences of these spaces reveals a highly admittant tympanic membrane and ossicular chain. Measurements of the admittance of the air spaces reveal that the high-degree of segmentation of these spaces has only a small effect on the admittance. Draining the cochlea further increases the middle-ear admittance at low frequencies and removes a low-frequency (less than 300 Hz) level dependence in the admittance. Spontaneous or sound-driven contractions of the middle-ear muscles in deeply anesthetized animals were associated with significant changes in middle-ear admittance. PMID:16944166

  6. High intensity anthropogenic sound damages fish ears.

    PubMed

    McCauley, Robert D; Fewtrell, Jane; Popper, Arthur N

    2003-01-01

    Marine petroleum exploration involves the repetitive use of high-energy noise sources, air-guns, that produce a short, sharp, low-frequency sound. Despite reports of behavioral responses of fishes and marine mammals to such noise, it is not known whether exposure to air-guns has the potential to damage the ears of aquatic vertebrates. It is shown here that the ears of fish exposed to an operating air-gun sustained extensive damage to their sensory epithelia that was apparent as ablated hair cells. The damage was regionally severe, with no evidence of repair or replacement of damaged sensory cells up to 58 days after air-gun exposure. PMID:12558299

  7. Gene expression profiling of the inner ear.

    PubMed

    Schimmang, Thomas; Maconochie, Mark

    2016-02-01

    The identification of transcriptional differences has served as an important starting point in understanding the molecular mechanisms behind biological processes and systems. The developmental biology of the inner ear, the biology of hearing and of course the pathology of deafness are all processes that warrant a molecular description if we are to improve human health. To this end, technological innovation has meant that larger scale analysis of gene transcription has been possible for a number of years now, extending our molecular analysis of genes to beyond those that are currently in vogue for a given system. In this review, some of the contributions gene profiling has made to understanding developmental, pathological and physiological processes in the inner ear are highlighted. PMID:26403558

  8. Diseases of the middle ear in childhood

    PubMed Central

    Minovi, Amir; Dazert, Stefan

    2014-01-01

    Middle ear diseases in childhood play an important role in daily ENT practice due to their high incidence. Some of these like acute otitis media or otitis media with effusion have been studied extensively within the last decades. In this article, we present a selection of important childhood middle ear diseases and discuss the actual literature concerning their treatment, management of complications and outcome. Another main topic of this paper deals with the possibilities of surgical hearing rehabilitation in childhood. The bone-anchored hearing aid BAHA and the active partially implantable device Vibrant Soundbridge could successfully be applied for children. In this manuscript, we discuss the actual literature concerning clinical outcomes of these implantable hearing aids. PMID:25587371

  9. An Ear-Worn Vital Signs Monitor.

    PubMed

    He, David Da; Winokur, Eric S; Sodini, Charles G

    2015-11-01

    This paper presents a wearable vital signs monitor at the ear. The monitor measures the electrocardiogram (ECG), ballistocardiogram (BCG), and photoplethysmogram (PPG) to obtain pre-ejection period (PEP), stroke volume (SV), cardiac output (CO), and pulse transit time (PTT). The ear is demonstrated as a natural anchoring point for the integrated sensing of physiological signals. All three signals measured can be used to obtain heart rate (HR). Combining the ECG and BCG allows for the estimation of the PEP, while combining the BCG and PPG allows for the measurement of PTT. Additionally, the J-wave amplitude of the BCG is correlated with the SV and, when combined with HR, yields CO. Results from a clinical human study on 13 subjects demonstrate this proof-of-concept device. PMID:26208264

  10. The mast cells of the inner ear.

    PubMed

    Sleeckx, J P; Shea, J J; Peremans, J M

    1976-01-01

    The presence of mast cells in the subepithelial connective tissue of the human endolymphatic sac has, to the best of our knowledge for the first time, been described. A hypothesis has been put forward in which these cells, which are known to contain histamin, heparin and serotonin, play an important role in the physiologic functions of the endolymphatic sac as well as in some pathologic states of the inner ear. PMID:1023741

  11. Why Do Elephants Flap Their Ears?

    NASA Astrophysics Data System (ADS)

    Koffi, Moise; Jiji, Latif; Andreopoulos, Yiannis

    2009-11-01

    It is estimated that a 4200 kg elephant generates as much as 5.12 kW of heat. How the elephant dissipates its metabolic heat and regulates its body temperature has been investigated during the past seven decades. Findings and conclusions differ sharply. The high rate of metabolic heat coupled with low surface area to volume ratio and the absence of sweat glands eliminate surface convection as the primary mechanism for heat removal. Noting that the elephant ears have high surface area to volume ratio and an extensive vascular network, ear flapping is thought to be the principal thermoregulatory mechanism. A computational and experimental program is carried out to examine flow and heat transfer characteristics. The ear is modeled as a uniformly heated oscillating rectangular plate. Our computational work involves a three-dimensional time dependent CFD code with heat transfer capabilities to obtain predictions of the flow field and surface temperature distributions. This information was used to design an experimental setup with a uniformly heated plate of size 0.2m x 0.3m oscillating at 1.6 cycles per second. Results show that surface temperature increases and reaches a steady periodic oscillation after a period of transient oscillation. The role of the vortices shed off the plate in heat transfer enhancement will be discussed.

  12. The glue ear 'epidemic': a historical perspective.

    PubMed

    Alderson, David

    2011-12-01

    This paper explores the historical context of the dramatic rise in surgery for glue ear in the mid-20th century, and questions the published assertion that this represented a manufactured 'epidemic'. In examining historical sources, the reader's theoretical viewpoint greatly influences their conclusions: the sustained rise in treatment for glue ear may be seen as the advance of science in a golden age or the resistance of insular professionals to reason in the light of new scientific study methods. Current views on the practice of medicine, consumerism, science and standardisation, rationing and the nature of 'truth' all affect the way that we see this period. Technological advances clearly allowed better diagnosis and more effective treatment, but these did not appear to drive an 'epidemic', rather they were developed to meet the pre-existing challenges of otological practice. The proposition that an 'epidemic' was created does not appear to have any solid grounding. Society's perception of what constitutes disease and what needs treatment may have evolved, but the prevalence of other important diseases changed dramatically over this time period, and a real change in the epidemiology of glue ear cannot be dismissed. In defining the case for and against surgical treatment, a solely positivist, quantitative worldview cannot give us a complete picture of benefit and risk to individuals, families and society at large. PMID:21653931

  13. Ear Recognition from One Sample Per Person

    PubMed Central

    Chen, Long; Mu, Zhichun; Zhang, Baoqing; Zhang, Yi

    2015-01-01

    Biometrics has the advantages of efficiency and convenience in identity authentication. As one of the most promising biometric-based methods, ear recognition has received broad attention and research. Previous studies have achieved remarkable performance with multiple samples per person (MSPP) in the gallery. However, most conventional methods are insufficient when there is only one sample per person (OSPP) available in the gallery. To solve the OSPP problem by maximizing the use of a single sample, this paper proposes a hybrid multi-keypoint descriptor sparse representation-based classification (MKD-SRC) ear recognition approach based on 2D and 3D information. Because most 3D sensors capture 3D data accessorizing the corresponding 2D data, it is sensible to use both types of information. First, the ear region is extracted from the profile. Second, keypoints are detected and described for both the 2D texture image and 3D range image. Then, the hybrid MKD-SRC algorithm is used to complete the recognition with only OSPP in the gallery. Experimental results on a benchmark dataset have demonstrated the feasibility and effectiveness of the proposed method in resolving the OSPP problem. A Rank-one recognition rate of 96.4% is achieved for a gallery of 415 subjects, and the time involved in the computation is satisfactory compared to conventional methods. PMID:26024226

  14. An investigation of ear necrosis in pigs

    PubMed Central

    Park, Jeonghwa; Friendship, Robert M.; Poljak, Zvonimir; DeLay, Josepha; Slavic, Durda; Dewey, Catherine E.

    2013-01-01

    Porcine ear necrosis was investigated in 23 conveniently chosen farms, consisting of 14 case farms and 9 control farms. Biopsies of lesions and oral swabs from pigs on 11 case farms were examined by histology and bacterial culture. All farms were visited for observations and a survey on management, housing, and the presence of other clinical signs or behavioral vices. Histological examination revealed that the lesions began on the surface and progressed to deeper layers, and that vascular damage did not appear to be the initiating cause. Spirochetes were only rarely observed in histological examination and were not cultured from biopsies and oral swabs. Staphylococcus aureus and Staphylococcus hyicus were cultured from 91% and 66% of samples, respectively. Ear biting and a humid environment were associated with ear necrosis. On some farms large numbers of pigs were affected and lesions were sometimes extensive. The condition appears to be an infectious disease beginning on the surface of the skin; contributing environmental and management factors are likely. PMID:24155434

  15. Arachidonic acid-dependent carbon-eight volatile synthesis from wounded liverwort (Marchantia polymorpha).

    PubMed

    Kihara, Hirotomo; Tanaka, Maya; Yamato, Katsuyuki T; Horibata, Akira; Yamada, Atsushi; Kita, Sayaka; Ishizaki, Kimitsune; Kajikawa, Masataka; Fukuzawa, Hideya; Kohchi, Takayuki; Akakabe, Yoshihiko; Matsui, Kenji

    2014-11-01

    Eight-carbon (C8) volatiles, such as 1-octen-3-ol, octan-3-one, and octan-3-ol, are ubiquitously found among fungi and bryophytes. In this study, it was found that the thalli of the common liverwort Marchantia polymorpha, a model plant species, emitted high amounts of C8 volatiles mainly consisting of (R)-1-octen-3-ol and octan-3-one upon mechanical wounding. The induction of emission took place within 40min. In intact thalli, 1-octen-3-yl acetate was the predominant C8 volatile while tissue disruption resulted in conversion of the acetate to 1-octen-3-ol. This conversion was carried out by an esterase showing stereospecificity to (R)-1-octen-3-yl acetate. From the transgenic line of M. polymorpha (des6(KO)) lacking arachidonic acid and eicosapentaenoic acid, formation of C8 volatiles was only minimally observed, which indicated that arachidonic and/or eicosapentaenoic acids were essential to form C8 volatiles in M. polymorpha. When des6(KO) thalli were exposed to the vapor of 1-octen-3-ol, they absorbed the alcohol and converted it into 1-octen-3-yl acetate and octan-3-one. Therefore, this implied that 1-octen-3-ol was the primary C8 product formed from arachidonic acid, and further metabolism involving acetylation and oxidoreduction occurred to diversify the C8 products. Octan-3-one was only minimally formed from completely disrupted thalli, while it was formed as the most abundant product in partially disrupted thalli. Therefore, it is assumed that the remaining intact tissues were involved in the conversion of 1-octen-3-ol to octan-3-one in the partially disrupted thalli. The conversion was partly promoted by addition of NAD(P)H into the completely disrupted tissues, suggesting an NAD(P)H-dependent oxidoreductase was involved in the conversion. PMID:25174554

  16. Predicting skin deficits through surface area measurements in ear reconstruction and adult ear surface area norms.

    PubMed

    Yazar, Memet; Sevim, Kamuran Zeynep; Irmak, Fatih; Yazar, Sevgi Kurt; Ye?ilada, Ay?in Karasoy; Kar?ida??, Semra Hacikerim; Tatlidede, Hamit Soner

    2013-07-01

    Ear reconstruction is one of the most challenging procedures in plastic surgery practice. Many studies and techniques have been described in the literature for carving a well-pronounced framework. However, just as important as the cartilage framework is the ample amount of delicate skin coverage of the framework. In this report, we introduce an innovative method of measuring the skin surface area of the auricle from a three-dimensional template created from the healthy ear.The study group consisted of 60 adult Turkish individuals who were randomly selected (30 men and 30 women). The participant ages ranged from 18 to 45 years (mean, 31.5 years), and they had no history of trauma or congenital anomalies. The template is created by dividing the ear into aesthetic subunits and using ImageJ software to estimate the necessary amount of total skin surface area required.Reconstruction of the auricle is a complicated process that requires experience and patience to provide the auricular details. We believe this estimate will shorten the learning curve for residents and surgeons interested in ear reconstruction and will help surgeons obtain adequate skin to drape over the well-sculpted cartilage frameworks by providing a reference list of total ear skin surface area measurements for Turkish men and women. PMID:23851770

  17. Pitfalls in the use of arachidonic acid oxidation products to assign lipoxygenase activity in cancer cells.

    PubMed

    Niknami, Marzieh; Dong, Qihan; Witting, Paul K

    2009-10-01

    Arachidonic acid (AA) reaction with cyclooxygenase (COX) and lipoxygenases (LOX) yield eicosanoids that can mediate prostate cancer proliferation and enhance both tumour vascularization and metastasis. Increasingly measurement of eicosanoids with liquid chromatography is employed to implicate LOX activity in different biological systems and in particular link LOX activity to the progression of cancer in experimental models. This study demonstrates that simply identifying patterns of eicosanoid regio-isomerism is insufficient to designate LOX activity in prostate cancer cells and the analysis must include complete stereochemical assignment of the various isomers in order to validate the assignment of LOX activity. PMID:19680997

  18. Synthesis of site-specifically deuterated arachidonic acid derivatives containing a remote tritium radiolabel

    PubMed Central

    McGinley, Chris M.; van der Donk, Wilfred A.

    2010-01-01

    Summary The synthesis of arachidonic acid derivatives containing site-specifically incorporated deuterium atoms and also a remote tritium label are described. Deuterium incorporation at the C11 and/or C15 position was achieved using Wittig chemistry, while the radiolabel was introduced at a remote position using [3H]NaBH4 as the radiolabel source. These compounds can be used to measure secondary kinetic isotope effects for both cyclooxygenase and lipoxygenase enzymes under aerobic turnover with high precision. PMID:20414469

  19. Phospholipase A2 and Arachidonic Acid in Alzheimers Disease

    PubMed Central

    Sanchez-Mejia, Rene O.; Mucke, Lennart

    2011-01-01

    Essential fatty acids (EFA) play a critical role in the brain and regulate many of the processes altered in Alzheimers disease (AD). Technical advances are allowing for the dissection of complex lipid pathways in normal and diseased states. Arachidonic acid (AA) and specific isoforms of phospholipase A2 (PLA2) appear to play critical mediator roles in amyloid-? (A?) - induced pathogenesis, leading to learning, memory, and behavioral impairments in mouse models of AD. These findings and ongoing research into lipid biology in AD and related disorders promise to reveal new pharmacological targets that may lead to better treatments for these devastating conditions. PMID:20553961

  20. Thiyl radical-induced cis-trans-isomerization of arachidonic acid inhibits prostaglandin metabolism

    NASA Astrophysics Data System (ADS)

    Kratzsch, S.; Drssler, K.; Sprinz, H.; Brede, Ortwin

    2003-06-01

    Thiyl radicals isomerize the olefinic bonds of natural all- cis-polyunsaturated fatty acids into their trans-state. Using low doses of gamma-irradiation we partially converted arachidonic acid (AA) by thiyl radical attack into its mono- trans-forms. The enzyme-driven prostaglandin metabolism was studied in these samples in liquid model as well as in in vivo conditions with four different detection methods. A dramatic inhibition of the metabolism explained by blocking of the cyclooxygenase by trans-isomers has been found.

  1. Production of arachidonic and linoleic acid metabolites by guinea pig tracheal epithelial cells

    SciTech Connect

    Oosthuizen, M.J.; Engels, F.; Van Esch, B.; Henricks, P.A.; Nijkamp, F.P. )

    1990-08-01

    Pulmonary epithelial cells may be responsible for regulating airway smooth muscle function, in part by release of fatty acid-derived mediators. Incubation of isolated guinea pig tracheal epithelial cells with radiolabeled arachidonic acid (AA) leads to the production of 5- and 15-hydroxyeicosatetraenoic acid (5- and 15-HETE) and smaller amounts of leukotriene (LT) B4 and C4 and 12-hydroxyheptadecatrienoic acid (HHT). Epithelial cells also are able to release linoleic acid (LA) metabolites. Incubation with radiolabeled linoleic acid leads to the formation of 9- and 13-hydroxyoctadecadienoic acid (9- and 13-HODE). The biological significance of these mediators produced by epithelial cells is discussed.

  2. Photoreactivation of ultraviolet radiation-induced release of arachidonic acid from marsupial cells.

    PubMed

    Kaleta, E W; Applegate, L A; Ley, R D

    1991-11-01

    Exposure of an established marsupial cell line, PtK2 (Potorous tridactylus), to ultraviolet radiation (UVR) from an FS-40 sunlamp (280-400 nm) resulted in a fluence-dependent release of radiolabeled arachidonic acid (AA) from cell membranes. Post-UVR, but not pre-UVR, exposure to photoreactivating light reversed UVR-induced pyrimidine dimers in DNA and suppressed the UVR-induced release of AA. These data indicate that DNA damage contributes to the release of AA from membrane phospholipids. PMID:1665911

  3. Sham Control Methods Used in Ear-Acupuncture/Ear-Acupressure Randomized Controlled Trials: A Systematic Review

    PubMed Central

    Zhang, Claire Shuiqing; Yang, Angela Weihong; Zhang, Anthony Lin; May, Brian H.

    2014-01-01

    Abstract Ear-acupuncture/ear-acupressure (EAP) has been used for a range of health conditions with numerous randomized controlled trials (RCTs) investigating its efficacy and safety. However, the design of sham interventions in these RCTs varied significantly. This study systematically reviewed RCTs on EAP for all clinical conditions involving a number of sham EAPs as a control intervention. The review is guided by the Cochrane Handbook for Systematic Reviews of Interventions 5.1.0 and investigated the types and differences of sham EAP interventions. Four electronic English databases (The Cochrane Library, PubMed, Embase, CINAHL®) and two Chinese databases (CQVIP, CNKI) were searched in December 2012 and 55 published RCTs comparing real and sham EAP for any clinical condition were included. Characteristics of participants, real and sham interventions, and outcomes were extracted. Four types of sham methods were identified. Among the 55 RCTs, 25 studies involved treatment on nonspecific ear acupoints as the sham method; seven studies used nonacupoints on the ear; nine studies selected placebo needles or placebo ear-acupressure on the same ear acupoints for the real treatment; 10 studies employed pseudo-intervention; and five studies combined two of the above methods to be the sham control. Other factors of treatment such as number of points, treatment duration, and frequency also varied greatly. Risk of bias assessment suggests that 32 RCTs were “high risk” in terms of participants blinding, and 45 RCTs were “high risk” in terms of personnel blinding. Meta-analysis was not conducted due to the high clinical heterogeneity across included studies. No relationship was found between the sham designs and efficacy outcomes, or between the sham types and dropout rate. No solid conclusion of which design is the most appropriate sham control of EAP could be drawn in this review. PMID:24138333

  4. Effects of ear-canal pressurization on middle-ear bone- and air-conduction responses

    PubMed Central

    Homma, Kenji; Shimizu, Yoshitaka; Kim, Namkeun; Du, Yu; Puria, Sunil

    2014-01-01

    In extremely loud noise environments, it is important to not only protect ones hearing against noise transmitted through the air-conduction (AC) pathway, but also through the bone-conduction (BC) pathways. Much of the energy transmitted through the BC pathways is concentrated in the mid-frequency range around 1.52 kHz, which is likely due to the structural resonance of the middle ear. One potential approach for mitigating this mid-frequency BC noise transmission is to introduce a positive or negative static pressure in the ear canal, which is known to reduce BC as well as AC hearing sensitivity. In the present study, middle-ear ossicular velocities at the umbo and stapes were measured using human cadaver temporal bones in response to both BC and AC excitations, while static air pressures of 400 mm H2O were applied in the ear canal. For the maximum negative pressure of ?400 mm H2O, mean BC stapes-velocity reductions of about 58 dB were observed in the frequency range from 0.8 to 2.5 kHz, with a peak reduction of 8.6( 4.7) dB at 1.6 kHz. Finite-element analysis indicates that the peak BC-response reduction tends to be in the mid-frequency range because the middle-ear BC resonance, which is typically around 1.52 kHz, is suppressed by the pressure-induced stiffening of the middle-ear structure. The measured data also show that the BC responses are reduced more for negative static pressures than for positive static pressures. This may be attributable to a difference in the distribution of the stiffening among the middle-ear components depending on the polarity of the static pressure. The characteristics of the BC-response reductions are found to be largely consistent with the available psychoacoustic data, and are therefore indicative of the relative importance of the middle-ear mechanism in BC hearing. PMID:19944139

  5. Changes in adrenergic nerves and tissue perfusion after freezing injury to the ear skin of rabbits.

    PubMed

    Junila, J

    1993-09-01

    The aim of the present study was to investigate by a combined trypan blue and catecholamine fluorescence technique the sequential changes in cutaneous adrenergic nerves, the distribution of blood flow, and vascular permeability at the demarcation line that occurred after experimental cold injury. Nine New Zealand white rabbits weighing 4.0-4.4 kg had frostbite induced by pressing the bottom of a glass bottle 2 cm in diameter filled with liquid nitrogen against the shaved skin of the ear. All the rabbits were anaesthetised with ketamine hydrochloride (Ketamine) and xylazine hydrochloride (Rompun). Specimens were taken one and three days, and two weeks after frostbite. Control samples were taken from the opposite normal ear. Trypan blue was injected into a saphenous vein just before the specimens were taken. The specimens were always taken in the same way and selected so that the probable demarcation line of the frostbite ran across the middle. The glyoxylic acid-induced fluorescence method was used to show the adrenergic nerves. There were no adrenergic nerves around the vessels and no arteriovenous anastomoses in the central area of the injury after one day, but catecholamines had started to accumulate in the adrenergic nerve endings at the margins of the injured area. This accumulation was still more obvious three days after frostbite. Some fluorescent regenerating adrenergic nerves could already be seen at the probable demarcation line two weeks after frostbite. There was increased trypan blue fluorescence near the margin of the injured area after one day, indicating extravasation and vascular damage.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8272767

  6. Inhibition by arachidonic acid and other fatty acids of dopamine uptake at the human dopamine transporter.

    PubMed

    Chen, Nianhang; Appell, Michael; Berfield, Janet L; Reith, Maarten E A

    2003-10-01

    It is known that arachidonic acid, in addition to promoting release of dopamine, can inhibit its transport. The present study provides preliminary information on structure-activity relationships for uptake inhibition by rotating disk voltammetry in human embryonic kidney-293 cells expressing the human dopamine transporter. Except for anandamide, all other fatty acids studied at a pretreatment concentration of 80 microM caused significant reductions in Vmax but not Km. Increasing saturation of the hydrocarbon tails (partial saturation: oleic acid, linoleic acid; full saturation: arachidic acid, stearic acid, stearic acid ethyl ester) removed inhibitory activity incrementally, suggesting a role for cis-unsaturation (folding/bending of hydrocarbon tails). The relative lack of effect of 5,8,11,14-eicosatetraynoic acid also supports the idea that less linear structures are less inhibitory on dopamine uptake. Esterification of the free carboxylic group (arachidonic acid ethyl ester) prevented most of the inhibitory activity, arguing against mere membrane lipid disruption. Finally, the endogenous cannabinoid anandamide greatly reduced uptake Vmax accompanied by a small decrease in Km, a potentially important effect on dopaminergic neurotransmission. PMID:14575792

  7. Evaluation of Bioequivalency and Toxicological Effects of Three Sources of Arachidonic Acid (ARA) in Domestic Piglets

    PubMed Central

    Tyburczy, Cynthia; Brenna, Margaret E.; DeMari, Joseph A.; Kothapalli, Kumar S. D.; Blank, Bryant S.; Valentine, Helen; McDonough, Sean P.; Banavara, Dattatreya; Diersen-Schade, Deborah A.; Brenna, J. Thomas

    2011-01-01

    Arachidonic acid (ARA) and docosahexaenoic acid (DHA) are routinely added to infant formula to support growth and development. We evaluated the bioequivalence and safety of three ARA-rich oils for potential use in infant formula using the neonatal pig model. The primary outcome for bioequivalence was brain accretion of ARA and DHA. Days 3 to 22 of age, domestic pigs fed one of three formulas, each containing ARA at ~0.64% and DHA at ~0.34% total fatty acids (FA). Control diet ARA was provided by ARASCO and all diets had DHA from DHASCO (Martek Biosciences Corp., Columbia, MD). The experimental diets a1 and a2 provided ARA from Refined Arachidonic acid-rich Oil (RAO; Cargill, Inc., Wuhan, China) and SUNTGA40S (Nissui, Nippon Suisan Kaisha, Ltd., Tokyo, Japan), respectively. Formula intake and growth were similar across all diets, and ARA was bioequivalent across treatments in the brain, retina, heart, liver and day 21 RBC. DHA levels in the brain, retina and heart were unaffected by diet. Liver sections, clinical chemistry, and hematological parameters were normal. We conclude that RAO and SUNTGA40S, when added to formula to supply ~0.64% ARA are safe and nutritionally bioequivalent to ARASCO in domestic piglets. PMID:21722692

  8. Arachidonic acid metabolism in the platelets and neutrophils of diabetic rabbit and human subjects

    SciTech Connect

    Greco, N.J.

    1985-01-01

    An alteration of arachidonic acid metabolism to prostaglandins and leukotrienes from platelets and polymorphonuclear leukocytes respectively is evident in subjects with diabetes mellitus. There is evidence of altered platelet/vascular wall interactions in diabetes mellitus and evidence that polymorphonuclear leukocytes influence the vascular walls. Theories on the pathogenesis of atherosclerosis include both blood cells. Platelet hypersensitivity is evident in those platelets from the alloxan-induced diabetic rabbit either suspended in plasma or buffer. Arachidonic acid- and collagen-induced platelet aggregation, release of /sup 14/serotonin, and T x B/sub 2/ and 12-HETE production is enhanced when responses of diabetic platelets are compared to control platelets. Control rabbit neutrophils produce more LTB/sub 4/, LTB/sub 4/ isomers and 5-HETE than diabetic rabbits neutrophils. Decreased synthesis from diabetic rabbit neutrophils is not explained by increased catabolism of LTB/sub 4/, reesterification of 5-HETE, or increased eicosanoid formation. These experiments demonstrate both platelet and neutrophil dysfunction in diabetic subjects. Because of the involvement of these cells in regulating circulatory homeostatis, abnormal behavior could aggravate the atherosclerotic process. Platelet and neutrophil dysfunctions are noted before macroscopic vascular lesions are apparent suggesting an important role in the pathogenesis of atherosclerosis.

  9. Association between polymorphisms of arachidonate 12-lipoxygenase (ALOX12) and schizophrenia in a Korean population.

    PubMed

    Kim, Tae; Kim, Hak-Jae; Park, Jin Kyung; Kim, Jong Woo; Chung, Joo-Ho

    2010-01-01

    Arachidonic acid (AA), an essential polyunsaturated fatty acid, is one of the major components of neural membranes, which show an altered phospholipid composition in schizophrenia. Arachidonate 12-lipoxygenase (ALOX12), an important enzyme, metabolizes AA to 12-HPETE, which affects catecholamine synthesis. However, research has yet to show the genetic association between ALOX12 and schizophrenia. Therefore, we investigated single nucleotide polymorphisms (SNP) of the ALOX12 gene in schizophrenia, recruiting patients with schizophrenia (n = 289) and normal controls (n = 306) from a Korean population. We selected three SNPs (rs1126667, rs434473, and rs1042357) of the ALOX12 gene and genotyped them by direct sequencing. We reviewed the schizophrenic patients' medical records and assessed them clinically using the Brief Psychiatric Rating Scale (BPRS), the Scale for the Assessment of Negative Symptoms (SANS), and the Operational Criteria Checklist (OPCRIT). Then we statistically analyzed the genetic associations between the SNPs and schizophrenia, finding a genetic association between both rs1126667 and rs1042357 and schizophrenia, in the recessive model (p = 0.015 and 0.015, respectively). We also found an association between rs434473 and negative symptoms, defined through a factor analysis of the OPCRIT data (p = 0.040). Consequently, we suggest that SNPs of the ALOX12 gene might be associated with schizophrenia and negative symptoms in this Korean population. These weak positives require additional study. PMID:20626912

  10. Inhibition of neutral sphingomyelinase decreases arachidonic acid mediated inflammation in liver ischemia-reperfusion injury

    PubMed Central

    Aslan, Mutay; Özcan, Filiz; Tuzcu, Hazal; Kıraç, Ebru; Elpek, Gulsum O

    2014-01-01

    This study aimed to determine the role of selective neutral sphingomyelinase (N-SMase) inhibition on arachidonic acid (AA) mediated inflammation following liver ischemia-reperfusion (IR) injury. Selective N-SMase inhibitor was administered via intraperitoneal injections. Liver IR injury was created by clamping blood vessels supplying the median and left lateral hepatic lobes for 60 min, followed by 60 min reperfusion. Levels of AA in liver tissue were determined by multiple reaction monitoring (MRM) using ultra fast-liquid chromatography (UFLC) coupled with tandem mass spectrometry (MS/MS). Phospholipase A2 (PLA2), cyclooxygenase (COX) and prostaglandin E2 (PGE2) were measured in liver tissue. Arachidonic acid levels, activity of PLA2, COX and PGE2 levels were significantly increased in postischemic liver tissue compared to nonischemic controls. N-SMase inhibition significantly decreased COX activity and PGE2 levels in postischemic liver. Future studies evaluating agents blocking N-SMase activity can facilitate the development of treatment strategies to alleviate inflammation in liver I/R injury. PMID:25550821

  11. Human immunodeficiency virus glycoprotein (gp120) induction of monocyte arachidonic acid metabolites and interleukin 1.

    PubMed Central

    Wahl, L M; Corcoran, M L; Pyle, S W; Arthur, L O; Harel-Bellan, A; Farrar, W L

    1989-01-01

    This study reports on the direct effect of the envelope glycoprotein (gp120) of the human immunodeficiency virus type 1 (HIV-1) on human monocyte function. Addition of preparations of purified gp120 from the HIV-1 to human monocytes resulted in the production of interleukin 1 (IL-1) and arachidonic acid metabolites from the cyclooxygenase and lipoxygenase pathways. Quantification of prostaglandin E2 (PGE2) and IL-1 revealed an increase in both mediators with 50 ng of gp120 per ml and an increase of 12- and 30- to 40-fold with 200-400 ng of gp120 per ml, respectively. Unlike native gp120, the recombinant nonglycosylated gp120 fragments PB1-RF and PB1-IIIB, as well as one of the core structural proteins of HIV-1, p24, did not increase arachidonic acid metabolism or IL-1 activity. Cytofluorometric analysis revealed that gp120 blocked the binding of OKT4A to the CD4 on monocytes, whereas OKT4 binding was unaffected. Involvement of the CD4 in signal transduction was further demonstrated by the ability of OKT4 and OKT4A monoclonal antibodies to increase monocyte PGE2, IL-1 activity, and nanogram amounts of IL-1 beta. PMID:2536171

  12. Omega-3 PUFAs Lower the Propensity for Arachidonic Acid Cascade Overreactions

    PubMed Central

    Lands, Bill

    2015-01-01

    A productive view of the benefits from omega-3 (n-3) nutrients is that the dietary essential omega-6 (n-6) linoleic acid has a very narrow therapeutic window which is widened by n-3 nutrients. The benefit from moderate physiological actions of the arachidonic acid cascade can easily shift to harm from excessive pathophysiological actions. Recognizing the factors that predispose the cascade to an unwanted overactivity gives a rational approach for arranging beneficial interactions between the n-3 and n-6 essential nutrients that are initial components of the cascade. Much detailed evidence for harmful cascade actions was collected by pharmaceutical companies as they developed drugs to decrease those actions. A remaining challenge is to understand the factors that predispose the cascade toward unwanted outcomes and create the need for therapeutic interventions. Such understanding involves recognizing the similar dynamics for dietary n-3 and n-6 nutrients in forming the immediate precursors of the cascade plus the more vigorous actions of the n-6 precursor, arachidonic acid, in forming potent mediators that amplify unwanted cascade outcomes. Tools have been developed to aid deliberate day-to-day quantitative management of the propensity for cascade overactivity in ways that can decrease the need for drug treatments. PMID:26301244

  13. Plasma phospholipid arachidonic acid and lignoceric acid are associated with the risk of cardioembolic stroke.

    PubMed

    Chung, Hye-Kyung; Cho, Yoonsu; Do, Hyun Ju; Oh, Kyungmi; Seo, Woo-Keun; Shin, Min-Jeong

    2015-11-01

    Cardioembolic (CE) stroke is the most severe subtype of ischemic stroke with high recurrence and mortality. However, there is still little information on the association of plasma fatty acid (FA) with CE stroke. The objective of this study was to test the hypothesis whether the composition of plasma phospholipid FA is associated with the risk of CE stroke. The study subjects were collected from the Korea University Stroke Registry. Twenty-one subjects were selected as CE stroke group, and 39 age- and sex-matched subjects with non-CE stroke were selected as controls. Sociodemographic factors, clinical measurements, and plasma phospholipid FA compositions were compared between the groups. Logistic regression was used to obtain estimates of the associations between the relevant FAs and CE stroke. The result showed that the CE stroke group had higher levels of free FA and lower levels of triglycerides before and after adjustment (all P < .05). In the regression analysis, elaidic acid (18:1Tn9) and arachidonic acid (20:4n6) were positively related, but lignoceric acid (24:0) was negatively related to CE stroke in all constructed models (all P < .05). In conclusion, plasma phospholipid FA composition was associated with CE stroke risk in Korean population, with higher proportions of elaidic acid and arachidonic acid and lower proportion of lignoceric acid in CE stroke. PMID:26452419

  14. Endogenous biosynthesis of arachidonic acid epoxides in humans: Increased formation in pregnancy-induced hypertension

    SciTech Connect

    Catella, F.; Lawson, J.A.; Fitzgerald, D.J.; FitzGerald, G.A. )

    1990-08-01

    Arachidonic acid is metabolized by means of P450 isoenzyme(s) to form epoxyeicosatrienoic acids (EETs) and their corresponding dihydroxy derivatives (DHETs). In the present study, we established the presence in human urine of 8,9-, 11,12-, and 14,15-EETs and their corresponding DHETs by developing quantitative assays and using negative ion, chemical ionization GC/MS and octadeuterated internal standards. Urinary excretion of 8,9- and 11,12-DHET increased in healthy pregnant women compared with nonpregnant female volunteers. By contrast, excretion of 11,12-DHET and 14,15-DHET, but not the 8,9-DHET regioisomer, increased even further in patients with pregnancy-induced hypertension. Intravenous administration of (3H)14,15-EET to three dogs markedly increased its DHET in plasma. The terminal half-life ranged from 7.9-12.3 min and the volume of distribution (3.5-5.3 liters) suggested limited distribution outside the plasma compartment. Negligible radioactivity was detected in urine; this fact infers that under physiological circumstances, urinary DHETs largely derive from the kidney. That P450 metabolites of arachidonic acid are formed in humans supports the hypothesis that these metabolites contribute to the physiological response to normal pregnancy and the pathophysiology of pregnancy-induced hypertension.

  15. Percentage oleic acid is inversely related to percentage arachidonic acid in total lipids of rat serum

    PubMed Central

    2013-01-01

    Background Since many health effects of oils rich in oleic acid (18:1, n-9) seem to be opposite those of arachidonic acid (20:4, n-6), i.e. concerning cardiovascular risk, we examined whether % 18:1 might be negatively associated with % 20:4. Methods Fatty acid separation by gas chromatography was performed in total serum lipids of 36 male rats. Using bivariate correlations and multiple linear regressions we studied the association between oleic acid and arachidonic acid. Results We found an inverse relationship (r = -0.885, p < 0.001; n = 36) between percentages of 18:1 and 20:4 in total lipids of rat serum, persisting when controlling for the other fatty acids measured. In a multiple linear regression model with % 20:4 as the dependent variable and percentages of the other fatty acids entered simultaneously as independents, oleic acid and linoleic acid contributed most to predict % 20:4. Per cent 20:4 correlated negatively (p< 0.01) with a Delta-9 desaturase index, i.e. the (18:1)/(18:0) ratio, and with the (20:4)/(18:2) ratio, estimating desaturases/elongase. Conclusions Percentages of 18:1 and 20:4 seem to be inversely related and desaturase/elongase inhibition could be involved. The results might partly explain positive health effects of foods rich in oleic acid. PMID:23521743

  16. Equine tracheal epithelial membrane strips - An alternate method for examining epithelial cell arachidonic acid metabolism

    SciTech Connect

    Gray, P.R.; Derksen, F.J.; Robinson, N.E.; Peter-Golden, M.L. Univ. of Michigan, Ann Arbor )

    1990-02-26

    Arachidonic acid metabolism by tracheal epithelium can be studied using enzymatically dispersed cell suspensions or cell cultures. Both techniques require considerable tissue disruption and manipulation and may not accurately represent in vivo activity. The authors have developed an alternate method for obtaining strips of equine tracheal epithelium without enzymatic digestion. In the horse, a prominent elastic lamina supports the tracheal epithelium. By physical splitting this lamina, they obtained strips ({le}12 x 1.5 cm) of pseudostratified columnar epithelium attached to a layer of elastic tissue 30-100 {mu}m thick. Epithelial strips (1.2 x 0.5 cm) were attached to plexiglass rods and incubated with ({sup 3}H)arachidonic acid in M199 medium (0.5 {mu}Ci/ml) for 24 hours at 37C. The strips incorporated 36{+-}4% (mean {+-} SEM) of the total radioactivity and released 8.0{+-}1.2% of incorporated radioactivity when stimulated by 5.0 {mu}M calcium ionophore A23187. The extracted supernatant was processed using HPLC, resulting in peaks of radioactivity that co-eluted with authentic PGE{sub 2}, PGF{sub 2}{alpha}, and 12-HETE standards. The greatest activity corresponded to the PGE{sub 2} and PGF{sub 2}{alpha} standards, which is a similar pattern to that reported for cultured human tracheal epithelium.

  17. Glucocorticoids shift arachidonic acid metabolism toward endocannabinoid synthesis: a non-genomic anti-inflammatory switch

    PubMed Central

    Malcher-Lopes, Renato; Franco, Alier; Tasker, Jeffrey G.

    2008-01-01

    Glucocorticoids are capable of exerting both genomic and non-genomic actions in target cells of multiple tissues, including the brain, which trigger an array of electrophysiological, metabolic, secretory and inflammatory regulatory responses. Here, we have attempted to show how glucocorticoids may generate a rapid anti-inflammatory response by promoting arachidonic acid-derived endocannabinoid biosynthesis. According to our hypothesized model, non-genomic action of glucocorticoids results in the global shift of membrane lipid metabolism, subverting metabolic pathways toward the synthesis of the anti-inflammatory endocannabinoids, anandamide (AEA) and 2-arachidonoyl-glycerol (2-AG), and away from arachidonic acid production. Post-transcriptional inhibition of cyclooxygenase-2 (COX2) synthesis by glucocorticoids assists this mechanism by suppressing the synthesis of pro-inflammatory prostaglandins as well as endocannabinoid-derived prostanoids. In the central nervous system (CNS) this may represent a major neuroprotective system, which may cross-talk with leptin signaling in the hypothalamus allowing for the coordination between energy homeostasis and the inflammatory response. PMID:18295199

  18. Endocannabinoid system modulates relapse to methamphetamine seeking: possible mediation by the arachidonic acid cascade.

    PubMed

    Anggadiredja, Kusnandar; Nakamichi, Masanori; Hiranita, Takato; Tanaka, Hiroyuki; Shoyama, Yukihiro; Watanabe, Shigenori; Yamamoto, Tsuneyuki

    2004-08-01

    We clarified the modulating action of the endocannabinoid system, and its possible mediation by the arachidonic acid cascade, on the reinstatement of methamphetamine (METH)-seeking behavior, using the intravenous self-administration paradigm in rats. Following 12 days of self-administration of METH, the replacement of METH with saline resulted in a gradual decrease in lever press responses (extinction). Under extinction conditions, METH-priming or re-exposure to cues previously paired with METH infusion markedly increased the responses (reinstatement of drug-seeking). The cannabinoid CB1 receptor antagonist, SR141716A, blocked this behavior. Although the cannabinoid agonist, Delta8-tetrahydrocannabinol (THC), had no effects by itself, coadministration of the agonist and METH at small doses reinstated the drug-seeking behavior. THC attenuated the effects of the reinstatement-inducing dose of METH, but enhanced the effect of cues. Either given repeatedly during the extinction or singly, 24 h before the first METH-priming or cues challenge, THC suppressed the reinstatement. In another set of experiments, we found that diclofenac, a cyclooxygenase inhibitor, also attenuated the reinstatement induced by exposure to cues or drug-priming. These results suggest that the endocannabinoid system, through possible mediation by the arachidonic acid cascade, serves as a modulator of the reinstating effects of METH-priming and cues. Extending the current view on the treatment of drug dependence, these results indicate that endocannabinoid-activating substances as well as cyclooxygenase inhibitors may be promising as antirelapse agents. PMID:15085091

  19. Manual therapy and ear pain: a report of four cases

    PubMed Central

    Murphy, Donald R.; Gay, Charles W.

    2011-01-01

    Purpose: To report and discuss four cases of ear pain which were treated successfully with manual therapy. Methods: Report of four cases. Results: Four patients with ear pain were referred for chiropractic consult. They were all treated with a combination of manual therapy and exercise with resolution of their ear symptoms. Conclusions: The mechanism of idiopathic ear pain that may be amenable to manual therapy is not fully known. Further research is needed to investigate the etiology of this disorder and to determine whether manual therapy and exercise are viable options in some patients with idiopathic ear pain. In the meantime, it may be advantageous for otolaryngologists to seek input from physicians skilled in assessment and treatment of the musculoskeletal system in cases ear pain for which an otolarygologic etiology cannot be found. PMID:21403781

  20. A preliminary theoretical model of hydrodynamics in the inner ear.

    PubMed

    Yu, Vivian M; Strykowski, Paul J; Odland, Rick M

    2010-04-01

    Head movement should create a transient pressure imbalance across the membranous inner ear. We used basic concepts of fluid dynamics to develop a theoretical model of the inner ear. According to this model, two contiguous fluidic systems-the perilymphatic system and the endolymphatic system-are in hydrostatic equilibrium across a compliant membrane. Our model demonstrates that changes in resistance or compliance in one system results in a transient distortion of the membranous inner ear until equilibrium between the two systems is restored. The concept of hydrodynamic pressure changes in the inner ear has received little attention, but it may represent a new approach to understanding the inner ear and treating inner ear diseases. PMID:20397144

  1. Computed Tomography Staging of Middle Ear Cholesteatoma

    PubMed Central

    Razek, Ahmed Abdel Khalek Abdel; Ghonim, Mohamed Rashad; Ashraf, Bassem

    2015-01-01

    Summary Background To establish computed tomography (CT) staging of middle ear cholesteatoma and assess its impact on the selection of the surgical procedure. Material/Methods Prospective study was conducted on 61 consecutive patients (mean age 26.8 years) with middle ear cholesteatoma. CT scan of the temporal bone and surgery were performed in all patients. CT staging classified cholesteatoma according to its location in the tympanic cavity (T); extension into the mastoid (M); and associated complications (C). Cholesteatoma was staged as stage I (T1, T2), stage II (T3, M1, M2, C1), and stage III (C2). Results The overall sensitivity of CT staging of cholesteatoma compared to surgery was 88% with excellent agreement and correlation between CT findings and intra-operative findings (K=0.863, r=0.86, P=0.001). There was excellent agreement and correlation of CT staging with surgical findings for T location (K=0.811, r=0.89, P=0.001), good for M extension (K=0.734, r=0.88, P=0.001), and excellent for associated C complications (K=1.00, r=1.0, P=0.001). Atticotympanotomy was carried out in stage I (n=14), intact canal wall surgery was performed in stage II (n=38), and canal wall down surgery was done in stage III (n=5) and stage II (n=4). Conclusions We established CT staging of middle ear cholesteatoma that helps surgeons to select an appropriate surgery. PMID:26171086

  2. STAT pathway in the regulation of zoledronic acid-induced apoptosis in chronic myeloid leukemia cells.

    PubMed

    Kiper, Hatice Demet; Tezcanli Kaymaz, Burcin; Gokbulut, Aysun Adan; Selvi, Nur; Avci, Cigir Biray; Kosova, Buket; Iskender, Guniz; Yandim, Melis Kartal; Gunduz, Cumhur; Sahin, Fahri; Baran, Yusuf; Saydam, Guray

    2013-07-01

    In this study, we aimed to evaluate the cytotoxic and apoptotic effects of zoledronic acid on K562 chronic myeloid leukemia (CML) cells and to examine the roles of STAT genes on zoledronic acid-induced apoptosis. The results showed that zoledronic acid decreased proliferation, and induced apoptosis in K562 cells in a dose- and time-dependent manner. mRNA and protein levels of STAT3, -5A and -5B genes were significantly reduced in zoledronic acid-treated K562 cells. These data indicated that STAT inhibition by zoledronic acid may be therapeutic in CML patients following the confirmation with clinical studies. PMID:23725755

  3. On hearing with more than one ear: lessons from evolution

    PubMed Central

    Schnupp, Jan W H; Carr, Catherine E

    2011-01-01

    Although ears capable of detecting airborne sound have arisen repeatedly and independently in different species, most animals that are capable of hearing have a pair of ears. We review the advantages that arise from having two ears and discuss recent research on the similarities and differences in the binaural processing strategies adopted by birds and mammals. We also ask how these different adaptations for binaural and spatial hearing might inform and inspire the development of techniques for future auditory prosthetic devices. PMID:19471267

  4. Epiphyseal, vertebral, and ear (EVE) dysplasia: a new syndrome?

    PubMed Central

    Amiel, J.; Cormier-Daire, V.; Journeau, P.; Mussat, P.; Munnich, A.; Lyonnet, S.

    1999-01-01

    We report on the association of epiphyseal, vertebral, and ear dysplasia in two sisters with normal stature and psychomotor development born to distantly related, healthy parents. This distinctive association has not been reported previously and is likely to represent a new condition with an autosomal recessive mode of inheritance. For this syndrome, we propose the acronym EVE standing for epiphyseal, vertebral, and ear dysplasia.???Keywords: epiphyseal; verterbal; and ear (EVE) dysplasia; new syndrome PMID:10424819

  5. Sebaceous Hyperplasia Mimicking Linear Wart over Ear

    PubMed Central

    Nair, Pragya A; Diwan, Nilofar G

    2015-01-01

    Sebaceous hyperplasia (SH), a common, benign condition of sebaceous gland, presents most commonly over face. Lesions are usually described as asymptomatic, soft, discrete, and yellow with a surface that ranges from smooth to slightly verrucous. The pathogenesis is not fully understood. It does not require treatment, but many time lesions can be cosmetically unfavorable than, need to be destroyed or excised. A case of 23-year-old male presenting with the skin colored to hyperpigmented linear hyperkeratotic plaque mimicking a wart, over the right ear is presented here, which was diagnosed as SH.

  6. Incorporating anthropometry into design of ear-related products.

    PubMed

    Liu, Bor-Shong

    2008-01-01

    To achieve mass customization and collaborative product design, human factors and ergonomics should play a key development role. The purpose of this study was to provide product designers with the anthropometic dimensions of outer ears for different demographic data, including gender and age. The second purpose was to compare the dimensions of various ear-related products (i.e., earphone, bluetooth earphone and ear-cup earphone) with the anthropometic database and recommend appropriate solutions for design. Two hundred subjects aged 20-59 was selected for this study and divided into four age stratifications. Further, three different dimensions of the outer ear (i.e., the earhole length, the ear connection length and the length of the pinna) were measured by superimposed grid photographic technique. The analysis of variance (ANOVA) was used to investigate the effects of gender, and age on ear dimensions. The results showed that all ear dimensions had significant gender effects. A comparison between the anthropometric dimensions and those of current products revealed that most current ear-related products need to be redesigned using anthropometric data. The shapes of earhole and pinna are not circular. Consequently, ear products need to be elongated so that users may feel more comfortably and not have the product slip off easily. PMID:17374520

  7. Customized tissue engineering for ear reconstruction.

    PubMed

    Staudenmaier, Rainer; Hoang, Nguyen The; Mandlik, Veronika; Schurr, Christian; Burghartz, Marc; Hauber, Katharina; Meier, Gerhard; Kadegge, Gnter; Blunk, Torsten

    2010-01-01

    Tissue engineering (TE) of cartilage for reconstructive surgery has proven to be a promising option for obtaining tissue for 3D structures that results in minimal donor site morbidity. Technological advances in this area are important since many defects can only be treated with customized implants. Most TE strategies rely on the use of resorbable 3D scaffolds to guide the growing tissue, with each tissue requiring a specific scaffold that has precisely defined properties depending on the physiological environment. Rapid prototyping (RP) technologies allow the fabrication of scaffolds of various geometric complexities from a variety of materials and as composites, while even allowing the inner architecture of the object to be varied in a defined manner at any given location. Scaffolds can be manufactured using RP techniques directly from computer aided design (CAD) data sources, e.g. via an STL file. The combination of TE and RP serves as the basis for the production of customized implants, for example the cartilage ear framework, and provides new perspectives for autologous ear reconstruction. PMID:20442566

  8. Enhanced visualization of inner ear structures

    NASA Astrophysics Data System (ADS)

    Niemczyk, Kazimierz; Kucharski, Tomasz; Kujawinska, Malgorzata; Bruzgielewicz, Antoni

    2004-07-01

    Recently surgery requires extensive support from imaging technologies in order to increase effectiveness and safety of operations. One of important tasks is to enhance visualisation of quasi-phase (transparent) 3d structures. Those structures are characterized by very low contrast. It makes differentiation of tissues in field of view very difficult. For that reason the surgeon may be extremly uncertain during operation. This problem is connected with supporting operations of inner ear during which physician has to perform cuts at specific places of quasi-transparent velums. Conventionally during such operations medical doctor views the operating field through stereoscopic microscope. In the paper we propose a 3D visualisation system based on Helmet Mounted Display. Two CCD cameras placed at the output of microscope perform acquisition of stereo pairs of images. The images are processed in real-time with the goal of enhancement of quasi-phased structures. The main task is to create algorithm that is not sensitive to changes in intensity distribution. The disadvantages of existing algorithms is their lack of adaptation to occuring reflexes and shadows in field of view. The processed images from both left and right channels are overlaid on the actual images exported and displayed at LCD's of Helmet Mounted Display. A physician observes by HMD (Helmet Mounted Display) a stereoscopic operating scene with indication of the places of special interest. The authors present the hardware ,procedures applied and initial results of inner ear structure visualisation. Several problems connected with processing of stereo-pair images are discussed.

  9. Obestatin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats

    PubMed Central

    Matuszyk, Aleksandra; Ceranowicz, Piotr; Warzecha, Zygmunt; Cieszkowski, Jakub; Bonior, Joanna; Jaworek, Jolanta; Kuśnierz-Cabala, Beata; Konturek, Peter; Ambroży, Tadeusz; Dembiński, Artur

    2016-01-01

    Obestatin, a 23-amino acid peptide derived from the proghrelin, has been shown to exhibit some protective and therapeutic effects in the gut. The aim of present study was to determine the effect of obestatin administration on the course of acetic acid-induced colitis in rats. Materials and Methods. Studies have been performed on male Wistar rats. Colitis was induced by a rectal enema with 3.5% acetic acid solution. Obestatin was administered intraperitoneally twice a day at a dose of 8 nmol/kg, starting 24 h after the induction of colitis. Seven or 14 days after the induction of colitis, the healing rate of the colon was evaluated. Results. Treatment with obestatin after induction of colitis accelerated the healing of colonic wall damage and this effect was associated with a decrease in the colitis-evoked increase in mucosal activity of myeloperoxidase and content of interleukin-1β. Moreover, obestatin administration significantly reversed the colitis-evoked decrease in mucosal blood flow and DNA synthesis. Conclusion. Administration of exogenous obestatin exhibits therapeutic effects in the course of acetic acid-induced colitis and this effect is related, at least in part, to the obestatin-evoked anti-inflammatory effect, an improvement of local blood flow, and an increase in cell proliferation in colonic mucosa. PMID:26798415

  10. Hepatoprotective effect of vitamin C on lithocholic acid-induced cholestatic liver injury in Gulo(-/-) mice.

    PubMed

    Yu, Su Jong; Bae, Seyeon; Kang, Jae Seung; Yoon, Jung-Hwan; Cho, Eun Ju; Lee, Jeong-Hoon; Kim, Yoon Jun; Lee, Wang Jae; Kim, Chung Yong; Lee, Hyo-Suk

    2015-09-01

    Prevention and restoration of hepatic fibrosis from chronic liver injury is essential for the treatment of patients with chronic liver diseases. Vitamin C is known to have hepatoprotective effects, but their underlying mechanisms are unclear, especially those associated with hepatic fibrosis. Here, we analyzed the impact of vitamin C on bile acid induced hepatocyte apoptosis in vitro and lithocholic acid (LCA)-induced liver injury in vitamin C-insufficient Gulo(-/-) mice, which cannot synthesize vitamin C similarly to humans. When Huh-BAT cells were treated with bile acid, apoptosis was induced by endoplasmic reticulum stress-related JNK activation but vitamin C attenuated bile acid-induced hepatocyte apoptosis in vitro. In our in vivo experiments, LCA feeding increased plasma marker of cholestasis and resulted in more extensive liver damage and hepatic fibrosis by more prominent apoptotic cell death and recruiting more intrahepatic inflammatory CD11b(+) cells in the liver of vitamin C-insufficient Gulo(-/-) mice compared to wild type mice which have minimal hepatic fibrosis. However, when vitamin C was supplemented to vitamin C-insufficient Gulo(-/-) mice, hepatic fibrosis was significantly attenuated in the liver of vitamin C-sufficient Gulo(-/-) mice like in wild type mice and this hepatoprotective effect of vitamin C was thought to be associated with both decreased hepatic apoptosis and necrosis. These results suggested that vitamin C had hepatoprotective effect against cholestatic liver injury. PMID:26057690

  11. STRUCTURAL REMODELING OF PROTEOGLYCANS UPON RETINOIC ACID-INDUCED DIFFERENTIATION OF NCCIT CELLS*

    PubMed Central

    Gasimli, Leyla; Stansfield, Hope E.; Nairn, Alison V.; Liu, Haiying; Paluh, Janet L.; Yang, Bo; Dordick, Jonathan S.; Moremen, Kelley W.; Linhardt, Robert J.

    2012-01-01

    Pluripotent and multipotent cells become increasingly lineage restricted through differentiation. Alterations to the cellular proteoglycan composition and structure should accompany these changes to influence cell proliferation, delineation of tissues and acquisition of cell migration capabilities. Retinoic acid plays an important role in pre-patterning of the early embryo. Retinoic acid can be used in vitro to induce differentiation, causing pluripotent and multipotent cells to become increasingly lineage restricted. We examined retinoic acid-induced changes in the cellular proteoglycan composition of the well-characterized teratocarcinoma line NCCIT. Our analysis revealed changes in the abundance of transcripts for genes encoding core proteins, enzymes that are responsible for early and late linkage region biosynthesis, as well as enzymes for GAG chain extension and modification. Transcript levels for genes encoding core proteins used as backbones for polysaccharide synthesis revealed highly significant increases in expression of lumican and decorin, 1500-fold and 2800-fold, respectively. Similarly, glypican 3, glypican 5, versican and glypican 6 showed increases between 5 and 70-fold. Significant decreases in biglycan, serglycin, glypican 4, aggrecan, neurocan, CD74 and glypican 1 were observed. Disaccharide analysis of the glycans in heparin/heparan sulfate and chondroitin/dermatan sulfate revealed retinoic acid-induced changes restricted to chondroitin/dermatan sulfate glycans. Our study provides the first detailed analysis of changes in the glycosaminoglycan profile of human pluripotent cells upon treatment with the retinoic acid morphogen. PMID:23053635

  12. Nucleic acid-induced antiviral immunity in invertebrates: an evolutionary perspective.

    PubMed

    Wang, Pei-Hui; Weng, Shao-Ping; He, Jian-Guo

    2015-02-01

    Nucleic acids derived from viral pathogens are typical pathogen associated molecular patterns (PAMPs). In mammals, the recognition of viral nucleic acids by pattern recognition receptors (PRRs), which include Toll-like receptors (TLRs) and retinoic acid-inducible gene (RIG)-I-like receptors (RLRs), induces the release of inflammatory cytokines and type I interferons (IFNs) through the activation of nuclear factor κB (NF-κB) and interferon regulatory factor (IRF) 3/7 pathways, triggering the host antiviral state. However, whether nucleic acids can induce similar antiviral immunity in invertebrates remains ambiguous. Several studies have reported that nucleic acid mimics, especially dsRNA mimic poly(I:C), can strongly induce non-specific antiviral immune responses in insects, shrimp, and oyster. This behavior shows multiple similarities to the hallmarks of mammalian IFN responses. In this review, we highlight the current understanding of nucleic acid-induced antiviral immunity in invertebrates. We also discuss the potential recognition and regulatory mechanisms that confer non-specific antiviral immunity on invertebrate hosts. PMID:24685509

  13. Obestatin Accelerates the Healing of Acetic Acid-Induced Colitis in Rats.

    PubMed

    Matuszyk, Aleksandra; Ceranowicz, Piotr; Warzecha, Zygmunt; Cieszkowski, Jakub; Bonior, Joanna; Jaworek, Jolanta; Ku?nierz-Cabala, Beata; Konturek, Peter; Ambro?y, Tadeusz; Dembi?ski, Artur

    2016-01-01

    Obestatin, a 23-amino acid peptide derived from the proghrelin, has been shown to exhibit some protective and therapeutic effects in the gut. The aim of present study was to determine the effect of obestatin administration on the course of acetic acid-induced colitis in rats. Materials and Methods. Studies have been performed on male Wistar rats. Colitis was induced by a rectal enema with 3.5% acetic acid solution. Obestatin was administered intraperitoneally twice a day at a dose of 8?nmol/kg, starting 24?h after the induction of colitis. Seven or 14 days after the induction of colitis, the healing rate of the colon was evaluated. Results. Treatment with obestatin after induction of colitis accelerated the healing of colonic wall damage and this effect was associated with a decrease in the colitis-evoked increase in mucosal activity of myeloperoxidase and content of interleukin-1?. Moreover, obestatin administration significantly reversed the colitis-evoked decrease in mucosal blood flow and DNA synthesis. Conclusion. Administration of exogenous obestatin exhibits therapeutic effects in the course of acetic acid-induced colitis and this effect is related, at least in part, to the obestatin-evoked anti-inflammatory effect, an improvement of local blood flow, and an increase in cell proliferation in colonic mucosa. PMID:26798415

  14. Expression in the human brain of retinoic acid induced 1, a protein associated with neurobehavioural disorders.

    PubMed

    Fragoso, Yara Dadalti; Stoney, Patrick N; Shearer, Kirsty D; Sementilli, Angelo; Nanescu, Sonia E; Sementilli, Pietro; McCaffery, Peter

    2015-03-01

    Retinoic acid induced 1 (RAI1) is a protein of uncertain mechanism of action which nevertheless has been the focus of attention because it is a major contributing factor in several human developmental disorders including Smith-Magenis and Potocki-Lupski syndromes. Further, RAI1 may be linked to adult neural disorders with developmental origins such as schizophrenia and autism. The protein has been extensively examined in the rodent but very little is known about its distribution in the human central nervous system. This study demonstrated the presence of RAI1 transcript in multiple regions of the human brain. The cellular expression of RAI1 protein in the human brain was found to be similar to that described in the mouse, with high levels in neurons, but not glia, of the dentate gyrus and cornus ammonis of the hippocampus. In the cerebellum, a second region of high expression, RAI1 was present in Purkinje cells, but not granule cells. RAI1 was also found in neurons of the occipital cortex. The expression of this retinoic acid-induced protein matched well in the hippocampus with expression of the retinoic acid receptors. The subcellular distribution of human neuronal RAI1 indicated its presence in both cytoplasm and nucleus. Overall, human RAI1 protein was found to be a highly expressed neuronal protein whose distribution matches well with its role in cognitive and motor skills. PMID:24519454

  15. NMDA receptor-mediated arachidonic acid release in neurons: role in signal transduction and pathological aspects.

    PubMed

    Lazarewicz, J W; Salinska, E; Wroblewski, J T

    1992-01-01

    The N-methyl-D-aspartate (NMDA)-sensitive subtype of glutamate receptor, which gates Ca(2+)-permeable ion channels, is known for its role in learning and memory formation, in the induction of long-term potentiation, and also in seizure activity and neurotoxicity. In primary cultures of cerebellar neurons, agonists of NMDA receptors induce a dose-dependent release of [3H]arachidonic acid ([3H]AA), which is potentiated by activation of the glycine-positive modulatory site and inhibited by NMDA receptor antagonists. NMDA receptor-induced [3H]AA release is inhibited by quinacrine and partially depends on the presence of extracellular calcium. The [3H]AA release is not sensitive, however, to pretreatment with pertussis or cholera toxin, which suggests a Ca(2+)-dependent activation of phospholipase A2 not employing G proteins. Pretreatment of cultures with the natural and semisynthetic sphingolipids GT1b and PKS 3, respectively, inhibits NMDA receptor-mediated [3H]AA release. We also demonstrated glutamate-evoked [3H]AA release from rat hippocampal slices, which is NMDA receptor mediated, calcium dependent and sensitive to quinacrine. Arachidonic acid and its metabolites have been shown to play a role as second messengers and to modulate neuronal activity. Moreover, they are thought to act as transsynaptic modulators in the mechanism of NMDA receptor-induced long-term potentiation in the hippocampus. Their role in ischemic brain pathology has also been postulated. Our experiments on cultured cerebellar granule cells, incubated in a Mg(2+)-free medium deprived of glucose and oxygen, demonstrated a time-dependent stimulation of [3H]AA release. This release was inhibited by antagonists of NMDA receptors and by quinacrine. Stimulation of NMDA-sensitive glutamate receptors and the subsequent calcium-mediated activation of phospholipase A2 may play a role in the in vivo release of arachidonic acid during brain ischemia. This hypothesis is supported by the observation that the enhanced level of thromboxane B2 in the gerbil brain after 5 min of global ischemia is reduced by the systemic application of either the NMDA antagonist MK-801 or the ganglioside GM1. PMID:1386178

  16. Acute doxorubicin cardiotoxicity alters cardiac cytochrome P450 expression and arachidonic acid metabolism in rats

    SciTech Connect

    Zordoky, Beshay N.M.; Anwar-Mohamed, Anwar; Aboutabl, Mona E.

    2010-01-01

    Doxorubicin (DOX) is a potent anti-neoplastic antibiotic used to treat a variety of malignancies; however, its use is limited by dose-dependent cardiotoxicity. Moreover, there is a strong correlation between cytochrome P450 (CYP)-mediated arachidonic acid metabolites and the pathogenesis of many cardiovascular diseases. Therefore, in the current study, we have investigated the effect of acute DOX toxicity on the expression of several CYP enzymes and their associated arachidonic acid metabolites in the heart of male Sprague-Dawley rats. Acute DOX toxicity was induced by a single intraperitoneal injection of 15 mg/kg of the drug. Our results showed that DOX treatment for 24 h caused a significant induction of CYP1A1, CYP1B1, CYP2C11, CYP2J3, CYP4A1, CYP4A3, CYP4F1, CYP4F4, and EPHX2 gene expression in the heart of DOX-treated rats as compared to the control. Similarly, there was a significant induction of CYP1A1, CYP1B1, CYP2C11, CYP2J3, CYP4A, and sEH proteins after 24 h of DOX administration. In the heart microsomes, acute DOX toxicity significantly increased the formation of 20-HETE which is consistent with the induction of the major CYP omega-hydroxylases: CYP4A1, CYP4A3, CYP4F1, and CYP4F4. On the other hand, the formation of 5,6-, 8,9-, 11,12-, and 14,15-epoxyeicosatrienoic acids (EETs) was significantly reduced, whereas the formation of their corresponding dihydroxyeicosatrienoic acids was significantly increased. The decrease in the cardioprotective EETs can be attributed to the increase of sEH activity parallel to the induction of the EPHX2 gene expression in the heart of DOX-treated rats. In conclusion, acute DOX toxicity alters the expression of several CYP and sEH enzymes with a consequent alteration in arachidonic acid metabolism. These results may represent a novel mechanism by which this drug causes progressive cardiotoxicity.

  17. Probing the Xenopus laevis inner ear transcriptome for biological function

    PubMed Central

    2012-01-01

    Background The senses of hearing and balance depend upon mechanoreception, a process that originates in the inner ear and shares features across species. Amphibians have been widely used for physiological studies of mechanotransduction by sensory hair cells. In contrast, much less is known of the genetic basis of auditory and vestibular function in this class of animals. Among amphibians, the genus Xenopus is a well-characterized genetic and developmental model that offers unique opportunities for inner ear research because of the amphibian capacity for tissue and organ regeneration. For these reasons, we implemented a functional genomics approach as a means to undertake a large-scale analysis of the Xenopus laevis inner ear transcriptome through microarray analysis. Results Microarray analysis uncovered genes within the X. laevis inner ear transcriptome associated with inner ear function and impairment in other organisms, thereby supporting the inclusion of Xenopus in cross-species genetic studies of the inner ear. The use of gene categories (inner ear tissue; deafness; ion channels; ion transporters; transcription factors) facilitated the assignment of functional significance to probe set identifiers. We enhanced the biological relevance of our microarray data by using a variety of curation approaches to increase the annotation of the Affymetrix GeneChip® Xenopus laevis Genome array. In addition, annotation analysis revealed the prevalence of inner ear transcripts represented by probe set identifiers that lack functional characterization. Conclusions We identified an abundance of targets for genetic analysis of auditory and vestibular function. The orthologues to human genes with known inner ear function and the highly expressed transcripts that lack annotation are particularly interesting candidates for future analyses. We used informatics approaches to impart biologically relevant information to the Xenopus inner ear transcriptome, thereby addressing the impediment imposed by insufficient gene annotation. These findings heighten the relevance of Xenopus as a model organism for genetic investigations of inner ear organogenesis, morphogenesis, and regeneration. PMID:22676585

  18. Cauliflower Ear and Skin Infections among Wrestlers in Tehran

    PubMed Central

    Kordi, Ramin; Mansournai, Mohammad Ali; Nourian, Roh Allah; Wallace, W. Angus

    2007-01-01

    The purpose of the study was to describe the magnitude of the selected sports medicine problems (i.e. cauliflower ear and skin infections) among wrestlers in Tehran. A number of 411 wrestlers were randomly selected from wrestling clubs in Tehran employing cluster sample setting method. The participants were interviewed using a specially designed and validated questionnaire. Nearly half of the participants (44%) had cauliflower ears. Only 23% of these participants had received any kind of treatment for their acute ear haematomas that are known to result in cauliflower ears. The prevalence of reported hearing loss among participants with cauliflower ears (11.5%, 95%CI: 6.9 to 16.2) was significantly more than this prevalence among those participants without cauliflower ears (1.8%, 95%CI: 0.1 to 3.5) (p < 0.05). More than half of the participants (52%) had skin infection diagnosed by a physician during the previous year. This study has identified evidence of an increase in hearing loss as a possible side effect of either cauliflower ear or ear injury in wrestling in Iran. There has been an outbreak of ringworm and there is a significant potential for an outbreak of impetigo among wrestlers in Tehran. Key points Skin infections are prevalent among wrestlers in Tehran. Commonly wrestlers in Tehran continue to carry out wrestling training while affected by skin infections. Cauliflower ear is common among wrestlers in Tehran. More research is needed to investigate hearing loss as a possible side effect of either cauliflower ear or ear injury in wrestling in Iran. PMID:24198702

  19. Plasma oxylipin profiling identifies polyunsaturated vicinal diols as responsive to arachidonic acid and docosahexaenoic acid intake in growing piglets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The dose-responsiveness of plasma oxylipins to incremental dietary intake of arachidonic (20:4n-6; ARA) and docosahexaenoic (22:6n-3; DHA) acid was determined in piglets. Piglets randomly received one of six formulas (n=8 per group) from day 3 to 27 postnatally. Diets contained varying ARA and DHA l...

  20. Role of arachidonic acid metabolism in transcriptional induction of tumor necrosis factor gene expression by phorbol ester

    SciTech Connect

    Horiguchi, J.; Spriggs, D.; Imamura, K.; Stone, R.; Luebbers, R.; Kufe, D.

    1989-01-01

    The treatment of human HL-60 promyelocytic leukemia cells with 12-0 tetradecanoylphorbol-13-acetate (TPA) is associated with induction of tumor necrosis factor (TNF) transcripts. The study reported here has examined TPA-induced signaling mechanisms responsible for the regulation of TNF gene expression in these cells. Run-on assays demonstrated that TPA increases TNS mRNA levels by transcriptional activation of this gene. The induction of TNF transcripts by TPA was inhibited by the isoquinolinesulfonamide derivative H7 but not by HA1004, suggesting that this effect of TPA is mediated by activation of protein kinase C. TPA treatment also resulted in increased arachidonic acid release. Moreover, inhibitors of phospholipase, A/sub 2/ blocked both the increase in arachidonic acid release and the induction of TNF transcripts. These findings suggest that TPA induces TNF gene expression through the formation of arachidonic acid metabolites. Although indomethacin had no detectable effect on this induction of TNF transcripts, ketoconazole, an inhibitor of 5-lipoxygenase, blocked TPA-induced increases in TNF mRNA levels. Moreover, TNF mRNA levels were increased by the 5-lipoxygenase metabolite leukotriene B/sub 4/. In contrast, the cyclooxygenase metabolite prostaglandin E/sub 2/ inhibited the induction of TNF transcripts by TPA. Taken together, these results suggest that TPA induces TNF gene expression through the arachidonic acid cascade and that the level of TNF transcripts is regulated by metabolites of the pathway, leukotriene B/sub 4/ and prostaglandin E/sub 2/.

  1. Increased neuroinflammatory and arachidonic acid cascade markers, and reduced synaptic proteins, in brain of HIV-1 transgenic rats

    PubMed Central

    2012-01-01

    Correction to Rao J S, Kim H W, Kellom M, Greenstein D, Chen M, Kraft A D, Harry G J, Rapoport S I, Basselin M. Increased neuroinflammatory and arachidonic acid cascade markers, and reduced synaptic proteins, in brain of HIV-1 transgenic rats. Journal of Neuroinflammation 8:101.

  2. IDENTIFICATION AND FUNCTIONAL CHARACTERIZATION OF THE MOSS PHYSCOMITRELLA PATENS DELTA5-DESATURASE GENE INVOLVED IN ARACHIDONIC AND EICOSAPENTAENOIC ACID BIOSYNTHESIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The moss Physcomitrella patens contains high levels of arachidonic acid and lesser amounts of eicosapentaenoic acid. In general, these C20 polyunsaturated fatty acids are synthesized from linoleic and alpha-linolenic acids, respectively, by a series of reactions catalyzed by a delta6-desaturase, an ...

  3. Mechanism for release of arachidonic acid during guinea pig platelet aggregation: a role for the diacylglycerol lipase inhibitor RHC 80267

    SciTech Connect

    Amin, D.

    1986-01-01

    The mechanism of the release of arachidonic acid from phospholipids after the stimulation of guinea pig platelets with collagen, thrombin and platelet activating factor (PAF) was studied. RHC 80267, a diacylglycerol lipase inhibitor, and indomethacin, a cyclooxygenase inhibitor, were used. Various in vitro assays for enzymes involved in arachidonic acid release and metabolism were conducted. Platelet aggregation and simultaneous release of ADP from platelets were monitored using a Chrono-log Lumiaggregometer. Platelets were labeled with (/sup 14/C)arachidonic acid to facilitate sensitive determination of small changes in platelet phospholipids during platelet aggregation. In the present investigation it is shown that collagen, thrombin and PAF increased phospholipase C activity. It was also discovered that cyclooxygenase products were responsible for further stimulation (a positive feed-back) of phospholipase C activity, while diacylglycerol provided a negative feed-back control over receptor-stimulated phospholipase C activity and inhibited ADP release. The guinea pig platelet is an ideal model to study phospholipase C-diacylglycerol lipase pathway for the release of arachidonic acid from platelet phospholipids because it does not have any phospholipase A/sub 2/ activity. It was observed that cyclooxygenase products were responsible for collagen-induced guinea pig platelet aggregation. Indomethacin completely inhibited collagen-induced platelet aggregation, was less effective against thrombin, and had no effect on PAF-induced platelet aggregation. On the other hand, RHC 80267 was a powerful inhibitor of aggregation and ADP release induced by all three of these potent aggregating agents.

  4. Human tumour necrosis factor-alpha (TNF-alpha) directly stimulates arachidonic acid release in human neutrophils.

    PubMed Central

    Atkinson, Y H; Murray, A W; Krilis, S; Vadas, M A; Lopez, A F

    1990-01-01

    The ability of tumour necrosis factor-alpha (TNF-alpha) to directly stimulate phospholipid turnover from human neutrophils was studied. Stimulation with recombinant human (rH) TNF-alpha induced the release of significant amounts of radioactivity from [3H]arachidonic acid-labelled neutrophils. This stimulation was equipotent to that induced by the bacterial tripeptide formyl-methionyl-leucylphenylalanine (FMLP). The time of maximum stimulated release varied between donors, with the most common maximal stimulation being 45 min. Dose-response experiments indicated that 100-1000 U/ml rH TNF-alpha were required for the maximum stimulatory effect. High-performance liquid chromatography analysis of the supernatants revealed that the radioactivity was associated with arachidonic acid, but not with its metabolites, indicating that TNF-alpha stimulates the release of arachidonic acid from cellular phospholipids but does not stimulate its metabolism. A comparison of TNF-alpha with other cytokines indicated that stimulation of arachidonic acid release paralleled the 'priming' of neutrophils for enhanced superoxide production, raising the possibility that phospholipid turnover and priming of neutrophils are causally related. PMID:2162326

  5. Eicosanoids Derived From Arachidonic Acid and Their Family Prostaglandins and Cyclooxygenase in Psychiatric Disorders.

    PubMed

    Yui, Kunio; Imataka, George; Nakamura, Hiroyuki; Ohara, Naoki; Naito, Yukiko

    2015-11-26

    Arachidonic acid (AA)-derived lipid mediators are called eicosanoids. Eicosanoids have emerged as key regulators of a wide variety of physiological responses and pathological processes, and control important cellular processes. AA can be converted into biologically active compounds by metabolism by cyclooxygenases (COX). Beneficial effect of COX-2 inhibitor celecoxib add-on therapy has been reported in early stage of schizophrenia. Moreover, add-on treatment of celecoxib attenuated refractory depression and bipolar depression. Further, the COX/prostaglandin E pathway play an important role in synaptic plasticity and may be included in pathophysiology in autism spectrum disorders (ASD). In this regard, plasma transferrin, which is an iron mediator related to eicosanoid signaling, may be related to social impairment of ASD. COX-2 is typically induced by inflammatory stimuli in the majority of tissues, and the only isoform responsible for propagating the inflammatory response. Thus, COX-2 inhibitors considered as the best target for Alzheimer's disease. PMID:26521945

  6. Altered Arachidonate Distribution in Macrophages from Caveolin-1 Null Mice Leading to Reduced Eicosanoid Synthesis*

    PubMed Central

    Astudillo, Alma M.; Prez-Chacn, Gema; Meana, Clara; Balgoma, David; Pol, Albert; del Pozo, Miguel A.; Balboa, Mara A.; Balsinde, Jess

    2011-01-01

    In this work we have studied the effect of caveolin-1 deficiency on the mechanisms that regulate free arachidonic acid (AA) availability. The results presented here demonstrate that macrophages from caveolin-1-deficient mice exhibit elevated fatty acid incorporation and remodeling and a constitutively increased CoA-independent transacylase activity. Mass spectrometry-based lipidomic analyses reveal stable alterations in the profile of AA distribution among phospholipids, manifested by reduced levels of AA in choline glycerophospholipids but elevated levels in ethanolamine glycerophospholipids and phosphatidylinositol. Furthermore, macrophages from caveolin-1 null mice show decreased AA mobilization and prostaglandin E2 and LTB4 production upon cell stimulation. Collectively, these results provide insight into the role of caveolin-1 in AA homeostasis and suggest an important role for this protein in the eicosanoid biosynthetic response. PMID:21852231

  7. Liquid human milk fortifier significantly improves docosahexaenoic and arachidonic acid status in preterm infants.

    PubMed

    Berseth, C L; Harris, C L; Wampler, J L; Hoffman, D R; Diersen-Schade, D A

    2014-09-01

    We report the fatty acid composition of mother?s own human milk from one of the largest US cohorts of lactating mothers of preterm infants. Milk fatty acid data were used as a proxy for intake at enrollment in infants (n=150) who received human milk with a powder human milk fortifier (HMF; Control) or liquid HMF [LHMF; provided additional 12mg docosahexaenoic acid (DHA), 20mg arachidonic acid (ARA)/100mL human milk]. Mothers provided milk samples (n=129) and reported maternal DHA consumption (n=128). Infant blood samples were drawn at study completion (Study Day 28). Human milk and infant PPL fatty acids were analyzed using capillary column gas chromatography. DHA and ARA were within ranges previously published for US term and preterm human milk. Compared to Control HMF (providing no DHA or ARA), human milk fortified with LHMF significantly increased infant PPL DHA and ARA and improved preterm infant DHA and ARA status. PMID:24863250

  8. Neutrophil chemotaxis and arachidonic acid metabolism are not linked: evidence from metal ion probe studies

    SciTech Connect

    Turner, S.R.; Turner, R.A.; Smith, D.M.; Johnson, J.A.

    1986-03-05

    Heavy metal ions can inhibit arachidonic acid (AA) metabolism protect against ionophore cytotoxicity (ibid) and inhibit neutrophil chemotaxis. In this study they used Au/sup 3 +/, Zn/sup 2 +/, Cr/sup 3 +/, Mn/sup 2 +/ and Cu/sup 2 +/ as probes of the interrelationships among AA metabolism, ionophore-mediated cytotoxicity, and chemotaxis. Phospholipid deacylation was measured in ionophore-treated cells prelabeled with /sup 3/H-AA. Eicosanoid release from ionophore-treated cells was monitored by radioimmunoassay. Cytoprotection was quantitated as ability to exclude trypan blue. Chemotaxis toward f-met-leu-phe was measured by leading front analysis. The results imply that metal ions attenuate ionophore cytotoxicity by blocking phospholipid deacylation and eicosanoid release. In contrast to previous reports, no correlation between AA metabolism and chemotaxis was demonstrated, suggesting that these 2 processes are not linked.

  9. On the reaction of wheat lipoxygenase with arachidonic acid and its oxygenated derivatives.

    PubMed

    Heydeck, D; Wiesner, R; Khn, H; Schewe, T

    1991-01-01

    Lipoxygenase was purified from wheat kernels by means of ammonium sulfate precipitation, gel chromatography on Sephadex G-200 and anion exchange chromatography on DEAE-Sephadex A-50. Arachidonic acid was mainly converted by the wheat lipoxygenase to 5D-hydroperoxy-6E,8Z,11Z,14Z-eicosatetraenoic acid (5D8-HPETE) with other HPETE isomers including 8-HPETE being minor products. At higher concentrations of lipoxygenase, multiple oxygenation products such as 5,15-dihydroxyeicosatetraenoic acid (5,15-diHETE) and, to a lower extent, 8,15-diHETE and lipoxin isomers were detected after reduction of the hydroperoxy derivatives primarily formed. Similar results were obtained with 5D8- or 15L8-hydroxyeicosatetraenoic acid as substrate. Moreover, evidence was obtained for leukotriene A4 synthase activity of the wheat lipoxygenase. PMID:1907133

  10. Arachidonic acid diet attenuates brain Aβ deposition in Tg2576 mice.

    PubMed

    Hosono, Takashi; Nishitsuji, Kazuchika; Nakamura, Toshiyuki; Jung, Cha-Gyun; Kontani, Masanori; Tokuda, Hisanori; Kawashima, Hiroshi; Kiso, Yoshinobu; Suzuki, Toshiharu; Michikawa, Makoto

    2015-07-10

    The amyloid β-protein (Aβ) is believed to play a causative role in the development of Alzheimer's disease (AD). Because the amyloid precursor protein (APP), a substrate of Aβ, and β-secretase and γ-secretase complex proteins, which process APP to generate Aβ, are all membrane proteins, it is possible to assume that alterations in brain lipid metabolism modulate APP and/or Aβ metabolism. However, the role of polyunsaturated fatty acids in Aβ metabolism remains unknown. We report here that 9 months-treatment of Tg2576 mice with arachidonic acid (ARA)-containing (ARA+) diet prevented brain Aβ deposition in 17-month-old Tg2576 mice. APP processing to generate soluble APPα, CTF-β, and Aβ synthesis was attenuated in Tg2576 mice fed with the ARA+ diet. These findings suggest that ARA+ diet could prevent Aβ deposition through the alteration of APP processing in Tg2576 mice. PMID:25881896

  11. 21 CFR 344.12 - Ear drying aid active ingredient.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Ear drying aid active ingredient. 344.12 Section 344.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....12 Ear drying aid active ingredient. The active ingredient of the product consists of...

  12. CT of adenomas of the middle ear and mastoid cavity

    SciTech Connect

    Van Thong Ho; Rao, V.J.; Mikaelian, D.O.

    1996-03-01

    A case of mixed type adenoma of the middle ear and mastoid is presented in which CT showed complete opacification of the middle ear and mastoid air cells with bulging of the tympanic membrane but without ossicular or bony destruction. 7 refs., 1 figs.

  13. 21 CFR 344.12 - Ear drying aid active ingredient.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 5 2012-04-01 2012-04-01 false Ear drying aid active ingredient. 344.12 Section 344.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....12 Ear drying aid active ingredient. The active ingredient of the product consists of...

  14. 21 CFR 344.12 - Ear drying aid active ingredient.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 5 2014-04-01 2014-04-01 false Ear drying aid active ingredient. 344.12 Section 344.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....12 Ear drying aid active ingredient. The active ingredient of the product consists of...

  15. 21 CFR 344.12 - Ear drying aid active ingredient.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Ear drying aid active ingredient. 344.12 Section 344.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....12 Ear drying aid active ingredient. The active ingredient of the product consists of...

  16. 21 CFR 344.12 - Ear drying aid active ingredient.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false Ear drying aid active ingredient. 344.12 Section 344.12 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....12 Ear drying aid active ingredient. The active ingredient of the product consists of...

  17. Replantation of an avulsed ear, using a single arterial anastamosis.

    PubMed

    O'Toole, G; Bhatti, K; Masood, S

    2008-01-01

    Avulsion of the ear is relatively uncommon and replantation a technical challenge. A case in which an avulsed ear was successfully replanted using a single arterial anastamosis is described. The surgical difficulties encountered, the pharmaceutical approach to postoperative care and the problems which resulted from the lack of venous drainage are discussed. PMID:18061545

  18. Middle Ear Resonance and Acoustic Immittance Measures in Children.

    ERIC Educational Resources Information Center

    Hanks, Wendy D.; Rose, Katie J.

    1993-01-01

    This study established a normal middle ear resonance estimated from sweep frequency tympanometry, established normal equivalent ear canal volume, static acoustic admittance, and tympanometric peak pressure at 226 hertz in 90 children with normal hearing and 68 children with deafness, ages 6-15. No significant intergroup or age differences were

  19. [Significance of the ear in the determination of age].

    PubMed

    Röhm, E; Adam, E

    1986-01-01

    The morphology of human ear conch is said to be rather individual, but a perfect person-identification by this mean is not possible. It is demonstrated by photographs-made in a 15 years' interval-that ear conch and auricular area can be typically marked by proceeding age and specific diseases. PMID:3741048

  20. Preventing Cauliflower Ear with a Modified Tie-Through Technique.

    ERIC Educational Resources Information Center

    Dimeff, Robert J.; Hough, David O.

    1989-01-01

    Describes a quick, simple tie-through suture technique (in which a collodion packing is secured to the auricle with two buttons) for preventing cauliflower ear following external ear trauma in wrestlers and boxers. The technique ensures constant compression; multiple treatments for fluid reaccumulation are rarely necessary. (SM)

  1. Inner ear contribution to bone conduction hearing in the human.

    PubMed

    Stenfelt, Stefan

    2015-11-01

    Bone conduction (BC) hearing relies on sound vibration transmission in the skull bone. Several clinical findings indicate that in the human, the skull vibration of the inner ear dominates the response for BC sound. Two phenomena transform the vibrations of the skull surrounding the inner ear to an excitation of the basilar membrane, (1) inertia of the inner ear fluid and (2) compression and expansion of the inner ear space. The relative importance of these two contributors were investigated using an impedance lumped element model. By dividing the motion of the inner ear boundary in common and differential motion it was found that the common motion dominated at frequencies below 7 kHz but above this frequency differential motion was greatest. When these motions were used to excite the model it was found that for the normal ear, the fluid inertia response was up to 20 dB greater than the compression response. This changed in the pathological ear where, for example, otosclerosis of the stapes depressed the fluid inertia response and improved the compression response so that inner ear compression dominated BC hearing at frequencies above 400 Hz. The model was also able to predict experimental and clinical findings of BC sensitivity in the literature, for example the so called Carhart notch in otosclerosis, increased BC sensitivity in superior semicircular canal dehiscence, and altered BC sensitivity following a vestibular fenestration and RW atresia. PMID:25528492

  2. The maize rachis affects Aspergillus flavus movement during ear development

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aspergillus flavus expressing green fluorescent protein (GFP) was used to follow infection in ears of maize hybrids resistant and susceptible to the fungus. Developing ears were needle-inoculated with GFP-transformed A. flavus 20 days after silk emergence, and GFP fluorescence in the pith was evalu...

  3. The interaction between ear and sex differences and stimulus rate.

    PubMed

    Ismail, Hasnaa; Thornton, A Roger D

    2003-05-01

    Evoked otoacoustic emissions (EOAEs) are produced by the cochlea in response to acoustic stimuli and provide an objective and non-invasive measure of cochlear function. A new technique, based on maximum length sequences (MLSs), enables stimulus rates of up to 5000 clicks/s to be used. Conventional EOAE amplitude differs between ears and sexes, female subjects having responses of greater amplitude than male subjects and right ears larger responses than left ears. As a prerequisite to clinical use it is necessary to establish if these differences occur with the MLS OAE technique and whether they change with stimulus rate. Eighty ears of normally hearing adults between the ages of 18 and 40 years were tested. MLS OAEs were recorded at eight stimulus rates ranging from 40/s to 5000/s. Two stimulus levels and two recordings were made at each stimulus rate. Female subjects were found to have statistically significantly larger MLS OAEs than male subjects and gave larger amplitude responses in the right ears. The difference was not significant between male right and left ears. A rate effect was also demonstrated with the amplitude of the MLS OAEs decreasing with an increase in rate. The study provides normative data for MLS OAE testing and shows that females have MLS OAEs of larger amplitude than males and that as the click stimulus rate increases the significance of this difference decreases. Female right ears also have MLS OAEs of greater amplitude than female left ears. PMID:12742242

  4. 5-Lipoxygenase metabolites of arachidonic acid regulate volume decrease by mudpuppy red blood cells.

    PubMed

    Light, D B; Mertins, T M; Belongia, J A; Witt, C A

    1997-08-01

    We examined whether metabolites of arachidonic acid (AA) regulate K+ efflux during regulatory volume decrease (RVD) by mudpuppy red blood cells (RBCs). Volume regulation was inhibited by the phospholipase A2 antagonists mepacrine (10 microM) and ONO-RS-082 (10 microM); the inhibitory effect of ONO-RS-082 was reversed by gramicidin (5 microM). Eicosatetraynoic acid (ETYA, 100 microM), a general antagonist of AA metabolism, also blocked RVD. In addition, volume regulation was inhibited by the lipoxygenase pathway antagonist nordihydroguaiaretic acid (NDGA, 10 microM), the 5 lipoxygenase antagonists AA-861 (5 microM) and curcumin (20 microM), and by the 5-lipoxygenase activating protein inhibitor L-655,298 (5 microM). Inhibition by all four of these agents was reversed with gramicidin. In contrast, the 12- and 15-lipoxygenase pathway inhibitor ethyl-3,4-dihydroxy-benzylidene-cyanoacetate (EDBCA, 1 microM) and the cytochrome P-450 monooxygenase pathway blocker ketoconazole (20 microM) had no effect. On the other hand, the cyclooxygenase pathway inhibitor aspirin (100 microM) slightly enhanced RVD. Consistent with these findings, a K(+)-selective whole cell conductance responsible for K+ efflux during cell swelling was inhibited by ONO-RS-082 (10 microM), NDGA (10 microM), AA-861 (5 microM), curcumin (20 microM), and L-655,298 (5 microM). In contrast, EDBCA (1 microM), ketoconazole (20 microM), and indomethacin (10 microM) did not block this whole cell conductance. These results indicate that a channel mediating K+ loss during RVD is regulated by a 5-lipoxygenase metabolite of arachidonic acid. PMID:9263885

  5. The vasodilatation induced by hydroperoxy metabolites of arachidonic acid in the rat mesenteric and pulmonary circulation.

    PubMed Central

    d'Alarcao, M.; Corey, E. J.; Cunard, C.; Ramwell, P.; Uotila, P.; Vargas, R.; Wroblewska, B.

    1987-01-01

    The effects of 15-hydroperoxy metabolites of arachidonic acid on vascular tone were evaluated in the perfused mesenteric preparation, the isolated perfused lung and segments of pulmonary arteries of the rat. In the mesenteric preparation, precontracted with phenylephrine, both 15-hydroperoxy-5,8,11,13-eicosatetraenoic acid (15-HPETE, ED50 1.6 nmol) and 8,15-dihydroperoxy-5,9,11,13-eicosatetraenoic acid (8,15-diHPETE, ED50 0.3 nmol) induced dose-dependent vasodilatation, whereas 5,15-diHPETE (0.2-100 nmol) had no effect. Prostacyclin (ED50 0.01 nmol) was, however, more potent than the hydroperoxides. In the rat isolated lung, precontracted with the stable thromboxane agonist U-46619, dose-dependent decrease in the perfusion pressure occurred with 15-HPETE(ED50 40 nmol), 5,15-diHPETE (ED50 30 nmol) and 8, 15-diHPETE (ED50 7 nmol) while 13-hydroperoxide of linoleic acid had no effect. Prostacyclin was 10 times more potent than 8, 15-diHPETE. The vasodilator effects were not affected by indomethacin. In both endothelium intact and denuded rat pulmonary arteries the hydroperoxides 15-HPETE, 8,15-diHPETE, and 5,15-diPETE induced dose-dependent relaxation. The hydroperoxide, 8,15-diHPETE was at least 3 times more potent than 15-HPETE or 5,15--diHPETE. The hydroperoxides had no effect on the basal tone of vessel segments and the relaxation induced by 15-HPETE was not attenuated by methylene blue (5 microM). These data indicate that 8,15-diHPETE may be a significant endothelium-independent vasodilator product of arachidonate lipoxygenation. PMID:3607370

  6. Imaging upregulated brain arachidonic acid metabolism in HIV-1 transgenic rats.

    PubMed

    Basselin, Mireille; Ramadan, Epolia; Igarashi, Miki; Chang, Lisa; Chen, Mei; Kraft, Andrew D; Harry, G Jean; Rapoport, Stanley I

    2011-02-01

    Human immunodeficiency virus (HIV)-associated infection involves the entry of virus-bearing monocytes into the brain, followed by microglial activation, neuroinflammation, and upregulated arachidonic acid (AA) metabolism. The HIV-1 transgenic (Tg) rat, a noninfectious HIV-1 model, shows neurologic and behavioral abnormalities after 5 months of age. We hypothesized that brain AA metabolism would be elevated in older HIV-1 Tg rats in vivo. Arachidonic acid incorporation from the plasma into the brain of unanesthetized 7-to-9-month-old rats was imaged using quantitative autoradiography, after [1-(14)C]AA infusion. Brain phospholipase (PLA(2)) activities and eicosanoid concentrations were measured, and enzymes were localized by immunostaining. AA incorporation coefficients k* and rates J(in), measures of AA metabolism, were significantly higher in 69 of 81 brain regions in HIV-1 Tg than in control rats, as were activities of cytosolic (c)PLA(2)-IV, secretory (s)PLA(2), and calcium independent (i)PLA(2)-VI, as well as prostaglandin E(2) and leukotriene B(4) concentrations. Immunostaining of somatosensory cortex showed elevated cPLA(2)-IV, sPLA(2)-IIA, and cyclooxygenase-2 in neurons. Brain AA incorporation and other markers of AA metabolism are upregulated in HIV-1 Tg rats, in which neurologic changes and neuroinflammation have been reported. Positron emission tomography with [1-(11)C]AA could be used to test whether brain AA metabolism is upregulated in HIV-1-infected patients, in relation to cognitive and behavioral disturbances. PMID:20664612

  7. Rapid Stimulation of 5-Lipoxygenase Activity in Potato by the Fungal Elicitor Arachidonic Acid 1

    PubMed Central

    Bostock, Richard M.; Yamamoto, Hiroyuki; Choi, Doil; Ricker, Karin E.; Ward, Bernard L.

    1992-01-01

    The activity of lipoxygenase (LOX) in aged potato tuber discs increased by almost 2-fold following treatment of the discs with the fungal elicitor arachidonic acid (AA). Enzyme activity increased above that in untreated discs within 30 min after AA treatment, peaked at 1 to 3 h, and returned to near control levels by 6 h. The majority of the activity was detected in a soluble fraction (105,000g supernatant), but a minor portion was also associated with a particulate fraction enriched in microsomal membranes (105,000g pellet); both activities were similarly induced. 5-Hydroperoxyeicosatetraenoic acid was the principal product following incubation of these extracts with AA. Antibodies to soybean LOX strongly reacted with a protein with a molecular mass of approximately 95-kD present in both soluble and particulate fractions whose abundance generally corresponded with LOX activity in extracts. LOX activity was not enhanced by treatment of the discs with nonelicitor fatty acids or by branched ?-glucans from the mycelium of Phytophthora infestans. Prior treatment of the discs with abscisic acid, salicylhydroxamic acid, or n-propyl gallate, all of which have been shown to suppress AA induction of the hypersensitive response, inhibited the AA-induced increment in LOX activity. Cycloheximide pretreatment, which abolishes AA elicitor activity for other responses such as phytoalexin induction, did not inhibit LOX activity in water- or elicitor-treated discs but enhanced activity similar to that observed by AA treatment. The elicitor-induced increase in 5-LOX activity preceded or temporally paralleled the induction of other studied responses to AA, including the accumulation of mRNAs for 3-hydroxy-3-methylglutaryl coenzyme A reductase and phenylalanine ammonia lyase reported here. The results are discussed in relation to the proposed role of the 5-LOX in signal-response coupling of arachidonate elicitation of the hypersensitive response. Images Figure 4 Figure 7 PMID:16653144

  8. Imaging upregulated brain arachidonic acid metabolism in HIV-1 transgenic rats

    PubMed Central

    Basselin, Mireille; Ramadan, Epolia; Igarashi, Miki; Chang, Lisa; Chen, Mei; Kraft, Andrew D; Harry, G Jean; Rapoport, Stanley I

    2011-01-01

    Human immunodeficiency virus (HIV)-associated infection involves the entry of virus-bearing monocytes into the brain, followed by microglial activation, neuroinflammation, and upregulated arachidonic acid (AA) metabolism. The HIV-1 transgenic (Tg) rat, a noninfectious HIV-1 model, shows neurologic and behavioral abnormalities after 5 months of age. We hypothesized that brain AA metabolism would be elevated in older HIV-1 Tg rats in vivo. Arachidonic acid incorporation from the plasma into the brain of unanesthetized 7-to-9-month-old rats was imaged using quantitative autoradiography, after [1-14C]AA infusion. Brain phospholipase (PLA2) activities and eicosanoid concentrations were measured, and enzymes were localized by immunostaining. AA incorporation coefficients k* and rates Jin, measures of AA metabolism, were significantly higher in 69 of 81 brain regions in HIV-1 Tg than in control rats, as were activities of cytosolic (c)PLA2-IV, secretory (s)PLA2, and calcium independent (i)PLA2-VI, as well as prostaglandin E2 and leukotriene B4 concentrations. Immunostaining of somatosensory cortex showed elevated cPLA2-IV, sPLA2-IIA, and cyclooxygenase-2 in neurons. Brain AA incorporation and other markers of AA metabolism are upregulated in HIV-1 Tg rats, in which neurologic changes and neuroinflammation have been reported. Positron emission tomography with [1-11C]AA could be used to test whether brain AA metabolism is upregulated in HIV-1-infected patients, in relation to cognitive and behavioral disturbances. PMID:20664612

  9. Arachidonic acid metabolites do not mediate toluene diisocyanate-induced airway hyperresponsiveness in guinea pigs

    SciTech Connect

    Gordon, T.; Thompson, J.E.; Sheppard, D.

    1988-05-01

    Arachidonic acid metabolites have previously been demonstrated to mediate the airway hyperresponsiveness observed in guinea pigs and dogs after exposure to ozone. Guinea pigs were treated with indomethacin (a cyclooxygenase inhibitor), U-60,257 (piriprost, a 5-lipoxygenase inhibitor), or BW775c (a lipoxygenase and cyclooxygenase inhibitor) and exposed to air or 3 ppm TDI. Airway responsiveness to acetylcholine aerosol was examined 2 h after exposure. In control animals, the provocative concentration of acetylcholine which caused a 200% increase in pulmonary resistance over baseline (PC200) was significantly less (p less than 0.05) after exposure to TDI (8.6 +/- 2.0 mg/ml, geometric mean + geometric SE, n = 10) than after exposure to air (23.9 + 2.5 mg/ml, n = 14). The airway responsiveness to acetylcholine in animals treated with indomethacin or piriprost and exposed to TDI was not different from that of control animals exposed to TDI. Treatment with BW755c enhanced the airway hyperresponsiveness observed in animals exposed to TDI without altering the PC200 of animals exposed to air. The PC200 of animals treated with BW755c and exposed to TDI (2.3 + 0.8 mg/ml, n = 8) was significantly lower than the PC200 of control animals exposed to TDI (p less than 0.025). These results suggest that products of arachidonic acid metabolism are not responsible for TDI-induced airway hyperresponsiveness in guinea pigs. BW755c, however, appears to potentiate the TDI-induced airway hyperresponsiveness to acetylcholine by an as yet unidentified mechanism.

  10. In vitro and in vivo activities of arachidonic acid against Schistosoma mansoni and Schistosoma haematobium.

    PubMed

    El Ridi, Rashika; Aboueldahab, Marwa; Tallima, Hatem; Salah, Mohamed; Mahana, Noha; Fawzi, Samia; Mohamed, Shadia H; Fahmy, Omar M

    2010-08-01

    The development of arachidonic acid (ARA) for treatment of schistosomiasis is an entirely novel approach based on a breakthrough discovery in schistosome biology revealing that activation of parasite tegument-bound neutral sphingomyelinase (nSMase) by unsaturated fatty acids, such as ARA, induces exposure of parasite surface membrane antigens to antibody binding and eventual attrition of developing schistosomula and adult worms. Here, we demonstrate that 5 mM ARA leads to irreversible killing of ex vivo 1-, 3-, 4-, 5-, and 6-week-old Schistosoma mansoni and 9-, 10-, and 12-week-old Schistosoma haematobium worms within 3 to 4 h, depending on the parasite age, even when the worms were maintained in up to 50% fetal calf serum. ARA-mediated worm attrition was prevented by nSMase inhibitors, such as CaCl(2) and GW4869. Scanning and transmission electron microscopy revealed that ARA-mediated worm killing was associated with spine destruction, membrane blebbing, and disorganization of the apical membrane structure. ARA-mediated S. mansoni and S. haematobium worm attrition was reproduced in vivo in a series of 6 independent experiments using BALB/c or C57BL/6 mice, indicating that ARA in a pure form (Sigma) or included in infant formula (Nestle) consistently led to 40 to 80% decrease in the total worm burden. Arachidonic acid is already marketed for human use in the United States and Canada for proper development of newborns and muscle growth of athletes; thus, ARA has potential as a safe and cost-effective addition to antischistosomal therapy. PMID:20479203

  11. Effect of selenium and vitamin E deficiencies on the fate of arachidonic acid in rat isolated lungs

    SciTech Connect

    Uotila, P.; Puustinen, T.

    1985-06-01

    The fate of exogenous /sup 14/C-arachidonic acid (/sup 14/C-AA) was investigated in the isolated lungs of rats fed selenium and vitamin E deficient diet or diets supplemented with selenium and/or vitamin E. When 80 nmol of /sup 14/C-AA was infused into the pulmonary circulation most of the infused /sup 14/C-AA was found in different phospholipid and neutral lipid fractions of the perfused lungs. Only less than ten percent of the infused radioactivity was recovered in the perfusion effluent. The amount of arachidonate metabolites in the perfusion effluent was negligible, and most of the radioactivity in the perfusion effluent consisted of unmetabolized arachidonate. Selenium deficiency had no significant effect on the distribution of /sup 14/C-AA in different lung lipid fractions. However, in the lungs of vitamin E deficient rats the amount of radioactivity was slightly increased in the neutral lipid fraction, which was due to the increased amount of /sup 14/C-AA in the diacylglycerols. The amount of radioactivity was increased especially in the 1,3-diacylglycerols. The amount of radioactivity was increased especially in the 1,3-diacylglycerols. The amount of /sup 14/C-AA in the triacylglycerols and in different phospholipids was not significantly changed. The present study might indicate that selenium deficiency has no significant effect on the fate of exogenous arachidonic acid in isolated rat lungs, and that vitamin E deficiency would slightly increase the amount of arachidonic acid in the diacylglycerols.

  12. Anatomy of the Human Ear/Questions to Ask your Hearing Professional

    MedlinePLUS

    ... Section: Focus on Communication Anatomy of the Human Ear/ Questions to Ask your Hearing Professional Past Issues / ... A feeling of fullness or fluid in the ear Ringing in your ears (called tinnitus) Causes Aging ...

  13. Inner ear symptoms and disease: Pathophysiological understanding and therapeutic options

    PubMed Central

    Ciuman, Raphael R.

    2013-01-01

    In recent years, huge advances have taken place in understanding of inner ear pathophysiology causing sensorineural hearing loss, tinnitus, and vertigo. Advances in understanding comprise biochemical and physiological research of stimulus perception and conduction, inner ear homeostasis, and hereditary diseases with underlying genetics. This review describes and tabulates the various causes of inner ear disease and defines inner ear and non-inner ear causes of hearing loss, tinnitus, and vertigo. The aim of this review was to comprehensively breakdown this field of otorhinolaryngology for specialists and non-specialists and to discuss current therapeutic options in distinct diseases and promising research for future therapies, especially pharmaceutic, genetic, or stem cell therapy. PMID:24362017

  14. Segmentation algorithms for ear image data towards biomechanical studies.

    PubMed

    Ferreira, Ana; Gentil, Fernanda; Tavares, Joo Manuel R S

    2014-01-01

    In recent years, the segmentation, i.e. the identification, of ear structures in video-otoscopy, computerised tomography (CT) and magnetic resonance (MR) image data, has gained significant importance in the medical imaging area, particularly those in CT and MR imaging. Segmentation is the fundamental step of any automated technique for supporting the medical diagnosis and, in particular, in biomechanics studies, for building realistic geometric models of ear structures. In this paper, a review of the algorithms used in ear segmentation is presented. The review includes an introduction to the usually biomechanical modelling approaches and also to the common imaging modalities. Afterwards, several segmentation algorithms for ear image data are described, and their specificities and difficulties as well as their advantages and disadvantages are identified and analysed using experimental examples. Finally, the conclusions are presented as well as a discussion about possible trends for future research concerning the ear segmentation. PMID:22994296

  15. [Local drug therapy for inner ear hearing loss].

    PubMed

    Liebau, A; Plontke, S K

    2015-06-01

    The indications for local drug therapy of inner ear hearing loss include sudden sensorineural hearing loss, Menière's disease, autoimmune-associated hearing loss, ototoxicity as a side effect of other therapies, acute acoustic trauma and improvement of the safety and performance of cochlear implants. Various drugs are currently being used and tested for local treatment of inner ear hearing loss, including glucocorticoids, growth factors, apoptosis inhibitors, antioxidants, TNF-α inhibitors and antibodies. To further a better understanding of pharmacokinetics and the development of rational pharmacotherapy of the inner ear, the"liberation, absorption, distribution, metabolism, elimination" (LADME) principle can be applied to local therapy of the inner ear. Local application strategies can be differentiated into intratympanic applications to the middle ear cavity and direct intralabyrinthine or intracochlear applications. PMID:25008276

  16. Day care ear surgery: our experience of 4years.

    PubMed

    Khan, Mubarak M; Parab, Sapna R

    2012-09-01

    Day care surgery is gaining wide popularity not only in the West, but also in our country. We present our experience of 4years of day care surgery in otological practice. To identify the scope of day care ear surgery in our rural setup and to determine the rate of complications, if any, of day care ear surgery. A prospective study of major ear cases operated in M.I.M.E.R. Medical College and Sushrut ENT Hospital was carried out from January 2005 to December 2008 with a minimum follow up of 2years. In the period from 2005 to 2008, a total of 527 major ear cases were operated. There was re-admission of 5 operated patients (0.94%). The acceptance of day care ear surgery is enormous in our rural setup due to its obvious advantages. PMID:23998036

  17. Bovine chromosomal regions affecting rheological traits in acid-induced skim milk gels.

    PubMed

    Glantz, M; Gustavsson, F; Bertelsen, H P; Stålhammar, H; Lindmark-Månsson, H; Paulsson, M; Bendixen, C; Gregersen, V R

    2015-02-01

    The production of fermented milk products has increased worldwide during the last decade and is expected to continue to increase during the coming decade. The quality of these products may be optimized through breeding practices; however, the relations between cow genetics and technological properties of acid milk gels are not fully known. Therefore, the aim of this study was to identify chromosomal regions affecting acid-induced coagulation properties and possible candidate genes. Skim milk samples from 377 Swedish Red cows were rheologically analyzed for acid-induced coagulation properties using low-amplitude oscillation measurements. The resulting traits, including gel strength, coagulation time, and yield stress, were used to conduct a genome-wide association study. Single nucleotide polymorphisms (SNP) were identified using the BovineHD SNPChip (Illumina Inc., San Diego, CA), resulting in almost 621,000 segregating markers. The genome was scanned for putative quantitative trait loci (QTL) regions, haplotypes based on highly associated SNP were inferred, and the additive genetic effects of haplotypes within each QTL region were analyzed using mixed models. A total of 8 genomic regions were identified, with large effects of the significant haplotype explaining between 4.8 and 9.8% of the phenotypic variance of the studied traits. One major QTL was identified to overlap between gel strength and yield stress, the QTL identified with the most significant SNP closest to the gene coding for κ-casein (CSN3). In addition, a chromosome-wide significant region affecting yield stress on BTA 11 was identified to be colocated with PAEP, coding for β-lactoglobulin. Furthermore, the coagulation properties of the genetic variants within the 2 genes were compared with the coagulation properties identified by the patterns of the haplotypes within the regions, and it was discovered that the haplotypes were more diverse and in one case slightly better at explaining the phenotypic variance. Besides these significant QTL comprising the 2 milk proteins, 3 additional genes are proposed as possible candidates, namely RAB22A, CDH13, and STAT1, and all have previously been found to be expressed in the mammary gland. To our knowledge, this is the first attempt to map QTL regions for acid-induced coagulation properties. PMID:25529417

  18. Analysis of Earing in Deep Drawn Cups

    NASA Astrophysics Data System (ADS)

    Aretz, Holger; Aegerter, Johannes; Engler, Olaf

    2010-06-01

    The cup-drawing of a strongly anisotropic sheet metal is simulated using a commercial finite element software along with a user material subroutine. In order to accurately describe the plastic anisotropy of the material the well-known recent yield function `Yld2004-18p' is extended. Regarding the experimental characterization of the considered material the occurrence of dynamic strain aging lead to an oscillating signal of the width change of the tensile samples, which prevented a reliable determination of plastic strain ratios (r-values). Thus, an improved measurement concept was developed that leads to a very robust and reproducible determination of r-values. Furthermore, a novel plane-strain tensile test sample is presented which is used for the characterization of the plastic anisotropy in biaxial loading states. A quantitative comparison with measured earing profiles of deep drawn cups illustrates the predictive capabilities of the numerical simulation.

  19. Mechanics of the exceptional anuran ear

    PubMed Central

    Segenhout, Johannes M.; van Dijk, Pim

    2008-01-01

    The anuran ear is frequently used for studying fundamental properties of vertebrate auditory systems. This is due to its unique anatomical features, most prominently the lack of a basilar membrane and the presence of two dedicated acoustic end organs, the basilar papilla and the amphibian papilla. Our current anatomical and functional knowledge implies that three distinct regions can be identified within these two organs. The basilar papilla functions as a single auditory filter. The low-frequency portion of the amphibian papilla is an electrically tuned, tonotopically organized auditory end organ. The high-frequency portion of the amphibian papilla is mechanically tuned and tonotopically organized, and it emits spontaneous otoacoustic emissions. This high-frequency portion of the amphibian papilla shows a remarkable, functional resemblance to the mammalian cochlea. PMID:18386018

  20. Problems in alloplastic middle ear reconstruction.

    PubMed

    Blayney, A W; Williams, K R; Erre, J P; Lesser, T H; Portmann, M

    1992-01-01

    Alloplastic materials have been used in middle ear reconstruction since 1952. Biologically, biomaterials and specifically ceramics can be defined as being bioinert, bioactive or biodegradable; these terms being descriptive of the biochemical response provoked by the material in the host tissue. Various ceramics, carbons and polymers and their reactions have been studied by the author and his colleagues over the past 5 years utilising animal implantation and fibroblast culture studies aligned with experience from clinical usage. The qualities of the ideal alloplastic implant namely: biocompatibility, stabilisation and incorporation, the consistency of the implant and bioactive bonding and the biofunctionality or mechanics, are applied to the materials currently available. No single alloplastic material fulfills all criteria, the problems encountered in relation to the biomaterials are reported. A better understanding of the microstresses, fatigue and microfractures is necessary, before the ideal alloplastic biomaterial becomes available. PMID:1605000

  1. The prevalence of middle ear pathogens in the outer ear canal and the nasopharyngeal cavity of healthy young adults.

    PubMed

    De Baere, T; Vaneechoutte, M; Deschaght, P; Huyghe, J; Dhooge, I

    2010-07-01

    Culturing middle ear fluid samples from children with chronic otitis media with effusion (OME) using standard techniques results in the isolation of bacterial species in approximately 30-50% of the cases. Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis, the classic middle ear pathogens of acute otitis media, are involved but, recently, several studies suggested Alloiococcus otitidis as an additional pathogen. In the present study, we used species-specific PCRs to establish the prevalence, in both the nasopharyngeal cavity and the outer ear, of H. influenzae, M. catarrhalis, S. pneumoniae and A. otitidis. The study group consisted of 70 healthy volunteers (aged 19-22 years). The results indicate a high prevalence (>80%) of A. otitidis in the outer ear in contrast to its absence in the nasopharynx. H. influenzae was found in both the outer ear and the nasopharynx (6% and 14%, respectively), whereas S. pneumoniae and M. catarrhalis were found only in the nasopharynx (9% and 34%, respectively).A. otitidis, described as a fastidious organism, were able to be cultured using an optimized culture protocol, with prolonged incubation, which allowed the isolation of A. otitidis in five of the nine PCR-positive samples out of the total of ten samples tested. Given the absence of the outer ear inhabitant A. otitidis from the nasopharynx, its role in the aetiology of OME remains ambiguous because middle ear infecting organisms are considered to invade the middle ear from the nasopharynx through the Eustachian tube. PMID:19895585

  2. "Play It by Ear"--Teachers' Responses to Ear-Playing Tasks during One-to-One Instrumental Lessons

    ERIC Educational Resources Information Center

    Varvarigou, Maria

    2014-01-01

    This paper reports findings from the Ear-Playing Project in relation to the teaching strategies that 15 instrumental teachers adopted during one-to-one instrumental lessons whilst helping their students to copy music by ear from a recording. Overall, the teachers used a variety of strategies including singing and humming along with or without the…

  3. "Play It by Ear"--Teachers' Responses to Ear-Playing Tasks during One-to-One Instrumental Lessons

    ERIC Educational Resources Information Center

    Varvarigou, Maria

    2014-01-01

    This paper reports findings from the Ear-Playing Project in relation to the teaching strategies that 15 instrumental teachers adopted during one-to-one instrumental lessons whilst helping their students to copy music by ear from a recording. Overall, the teachers used a variety of strategies including singing and humming along with or without the

  4. A stochastic model featuring acid-induced gaps during tumor progression

    NASA Astrophysics Data System (ADS)

    Athni Hiremath, Sandesh; Surulescu, Christina

    2016-03-01

    In this paper we propose a phenomenological model for the formation of an interstitial gap between the tumor and the stroma. The gap is mainly filled with acid produced by the progressing edge of the tumor front. Our setting extends existing models for acid-induced tumor invasion models to incorporate several features of local invasion like formation of gaps, spikes, buds, islands, and cavities. These behaviors are obtained mainly due to the random dynamics at the intracellular level, the go-or-grow-or-recede dynamics on the population scale, together with the nonlinear coupling between the microscopic (intracellular) and macroscopic (population) levels. The wellposedness of the model is proved using the semigroup technique and 1D and 2D numerical simulations are performed to illustrate model predictions and draw conclusions based on the observed behavior.

  5. Characterization of acid-induced molten globule like state of ficin.

    PubMed

    Devaraj, K B; Kumar, Parigi Ramesh; Prakash, V

    2009-10-01

    Effect of pH on the conformational behaviour of ficin (EC 3.4.22.3), a cysteine protease from the latex of Ficus carica was monitored by circular dichroism, fluorescence spectroscopy, ANS binding and hydrodynamic studies. The results obtained from near- and far-UV CD, intrinsic fluorescence and ANS binding studies demonstrate that ficin exhibits the characteristic properties of molten globule at acidic conditions between pH 1.4 and 2.0. Ficin at pH 1.4 retained about approximately 74% secondary structure with a substantial loss of tertiary structure. The acid-induced state was found to have a compact shape as measured by Stokes radius on size exclusion chromatography. PMID:19482042

  6. Valproic Acid-Induced Severe Acute Pancreatitis with Pseudocyst Formation: Report of a Case.

    PubMed

    Ray, Sukanta; Khamrui, Sujan; Kataria, Mohnish; Biswas, Jayanta; Saha, Suman

    2015-08-01

    Valproic acid is the most widely used anti-epilep-tic drug in children, and it is probably the most frequent cause of drug-induced acute pancreatitis. Outcomes for patients with valproic acid-associated pancreatitis vary from full recovery after discontinuation of the drug to severe acute pancreatitis and death. Here, we present a case of valproic acid-induced severe acute pancreatitis with pseudocyst formation in a 10-year-old girl with cerebral palsy and generalized tonic-clonic seizure. There was no resolution of the pseudocyst after discontinuation of valproic acid. The patient became symptomatic with a progressive increase in the size of the pseudocyst. She was successfully treated with cystogastrostomy and was well at 12-month follow-up. PMID:26366333

  7. CA3 Synaptic Silencing Attenuates Kainic Acid-Induced Seizures and Hippocampal Network Oscillations123

    PubMed Central

    Yu, Lily M. Y.; Wintzer, Marie E.

    2016-01-01

    Abstract Epilepsy is a neurological disorder defined by the presence of seizure activity, manifest both behaviorally and as abnormal activity in neuronal networks. An established model to study the disorder in rodents is the systemic injection of kainic acid, an excitatory neurotoxin that at low doses quickly induces behavioral and electrophysiological seizures. Although the CA3 region of the hippocampus has been suggested to be crucial for kainic acid-induced seizure, because of its strong expression of kainate glutamate receptors and its high degree of recurrent connectivity, the precise role of excitatory transmission in CA3 in the generation of seizure and the accompanying increase in neuronal oscillations remains largely untested. Here we use transgenic mice in which CA3 pyramidal cell synaptic transmission can be inducibly silenced in the adult to demonstrate CA3 excitatory output is required for both the generation of epileptiform oscillatory activity and the progression of behavioral seizures.

  8. Passage of albumin from the middle ear to the inner ear in otitis media in the chinchilla

    SciTech Connect

    Goldberg, B.; Goycoolea, M.V.; Schleivert, P.M.; Shea, D.; Schachern, P.; Paparella, M.M.; Carpenter, A.M.

    1981-08-01

    A study of the permeability of the middle ear-inner ear interface for macromolecules was carried out in chinchillas with open and obstructed eustachian tubes utilizing tritiated human serum albumin and immunoelectrophoresis. Tritiated albumin was placed in the round window niche area or normal animals and animals in which the eustachian tubes had been obstructed for 24 hours or 14 days. The tritiated albumin was allowed to remain in the middle ear cavity for 24 hours, Samples of middle ear effusion, perilymph, blood and cerebrospinal fluid were collected and measured for radioactivity. Radioactivity was demonstrated in the perilymph. Samples of middle ear effusions and perilymph were also studied by immunoelectrophoresis with goat antihuman albumin. Albumin placed in the round window niche of an experimental animal could be recovered unchanged in the perilymph. The results suggest a pathophysiologic explanation for the association of otitis media and sensorineural hearing loss or endolymphatic hydrops.

  9. Montelukast potentiates the protective effect of rofecoxib against kainic acid-induced cognitive dysfunction in rats.

    PubMed

    Kumar, Anil; Prakash, Atish; Pahwa, Deeksha; Mishra, Jitendriya

    2012-11-01

    There is an evolving consensus that mild cognitive impairment (MCI) serves as a prodrome to Alzheimer's disease. Antioxidants and COX-2 (cyclo-oxygenase-2) inhibitors have also been reported to have beneficial effects against conditions of memory impairment. Newer drugs like cysteinyl leukotriene inhibitors have shown neuroprotective effect in animal models of ischemia. Thus, the present study purports to explore the potential role of montelukast (a cysteinyl leukotriene inhibitor) in concert with rofecoxib (COX-2 inhibitor) and caffeic acid (a 5-LOX inhibitor and potent antioxidant) against kainic acid induced cognitive dysfunction in rats. In the experimental protocol, kainic acid (0.4 ?g/2 ?l) in artificial cerebrospinal fluid (ACSF) was given intrahippocampally (CA3 region) to induce a condition similar to MCI. Memory performance was measured on days 10-14 and the locomotor activity was measured on days 1, 7 and 14. For estimation of biochemical, mitochondrial and histopathological parameters, animals were sacrificed on day 14, stored at -80 C and the estimation was done on the 15th day. The treatment groups consisting of montelukast (0.5 and 1 mg/kg), rofecoxib (5 and 10 mg/kg) and caffeic acid (5 and 10 mg/kg) showed significant improvement in memory performance, oxidative stress parameters and mitochondrial function as compared to that of control (kainic acid treated), however, combination of montelukast with rofecoxib showed significant improvement in their protective effect. Thus the present study emphasizes the positive modulation of cysteinyl leukotriene receptor inhibition on COX (cyclooxygenase) and LOX (lipoxygenase) pathways in the control of the neuroinflammation in kainic acid induced cognitive dysfunction in rats. PMID:22878042

  10. Dietary fish oil potentiates bile acid-induced cholesterol secretion into bile in rats.

    PubMed

    Smit, M J; Verkade, H J; Havinga, R; Vonk, R J; Scherphof, G L; In 't Veld, G; Kuipers, F

    1994-02-01

    Recently we demonstrated that dietary fish oil (FO) causes changes in intrahepatic cholesterol transport and hypersecretion of cholesterol into bile in rats (J. Clin. Invest. 88: 943-951, 1991). We have now investigated in more detail the relationship between cholesterol and bile acid secretion in rats with chronic bile diversion fed purified diets supplemented (9% wt/wt) with either FO or corn oil (CO) for 2 weeks. Effects of FO on biliary cholesterol secretion (+ 400% as compared to CO after 14 days) were much more pronounced than previously observed in rats with intact enterohepatic circulation (+50%). Biliary bile acid (+30%) and phospholipid (+120%) secretion were increased to a much lesser extent than that of cholesterol resulting in the formation of bile supersaturated with cholesterol. The biliary cholesterol/bile acid molar ratio was 0.069 and 0.032 in FO- and CO-fed rats, respectively, at noon of day 14. This ratio increased to 0.108 in FO-fed rats at midnight, when bile acid output was maximal, but remained unchanged in CO-fed rats during the day-night cycle. Intravenous administration of taurochenodeoxycholic acid (15 mumol/kg) resulted in a 2-fold increase in bile acid output and a simultaneous 1.6-fold stimulation of cholesterol secretion in both groups, implying that administration of the bile acid induced the secretion of 2-3 times as much cholesterol in FO- than in CO-fed rats. Likewise, administration of bilirubin ditaurate (30 mumol/kg), an inhibitor of bile acid-induced biliary lipid secretion, reduced cholesterol output in both groups by about 50% while bile acid output remained unchanged. It is concluded that, in rats, dietary fish oil increases the disposition of cholesterol into bile by potentiating bile acid-dependent cholesterol secretion, presumably by facilitating the recruitment of bile-destined cholesterol. PMID:8169534

  11. Proteomic Investigation into Betulinic Acid-Induced Apoptosis of Human Cervical Cancer HeLa Cells

    PubMed Central

    Xu, Tao; Pang, Qiuying; Zhou, Dong; Zhang, Aiqin; Luo, Shaman; Wang, Yang; Yan, Xiufeng

    2014-01-01

    Betulinic acid is a pentacyclic triterpenoid that exhibits anticancer functions in human cancer cells. This study provides evidence that betulinic acid is highly effective against the human cervical cancer cell line HeLa by inducing dose- and time-dependent apoptosis. The apoptotic process was further investigated using a proteomics approach to reveal protein expression changes in HeLa cells following betulinic acid treatment. Proteomic analysis revealed that there were six up- and thirty down-regulated proteins in betulinic acid-induced HeLa cells, and these proteins were then subjected to functional pathway analysis using multiple analysis software. UDP-glucose 6-dehydrogenase, 6-phosphogluconate dehydrogenase decarboxylating, chain A Horf6-a novel human peroxidase enzyme that involved in redox process, was found to be down-regulated during the apoptosis process of the oxidative stress response pathway. Consistent with our results at the protein level, an increase in intracellular reactive oxygen species was observed in betulinic acid-treated cells. The proteins glucose-regulated protein and cargo-selection protein TIP47, which are involved in the endoplasmic reticulum pathway, were up-regulated by betulinic acid treatment. Meanwhile, 14-3-3 family proteins, including 14-3-3? and 14-3-3?, were down-regulated in response to betulinic acid treatment, which is consistent with the decrease in expression of the target genes 14-3-3? and 14-3-3?. Furthermore, it was found that the antiapoptotic bcl-2 gene was down-regulated while the proapoptotic bax gene was up-regulated after betulinic acid treatment in HeLa cells. These results suggest that betulinic acid induces apoptosis of HeLa cells by triggering both the endoplasmic reticulum pathway and the ROS-mediated mitochondrial pathway. PMID:25148076

  12. Hydrostatic pressure in the inner ear fluid compartments and its effects on inner ear function.

    PubMed

    Bhmer, A

    1993-01-01

    The present study summarizes the experimental findings obtained on the pressure in the inner ear fluids and on the effects of pressure changes on cochlear function in the guinea pig. Two types of pressures have to be distinguished in the inner ear fluid compartments: (i) hydrostatic fluid pressure and (ii) superimposed hydrodynamic high frequency (> 100 Hz) sound pressure oscillations. Hydrostatic pressure in the inner ear fluids in guinea pigs is in the order of 200 Pa (2 cm H2O) and shows slow (< 5 Hz) respiratory and pulsatory oscillations as well as considerable physiological variations in the range of -100 to +700 Pa. In normal ears, hydrostatic pressure in the perilymph equals pressure in the endolymph, and pressure changes applied to one compartment are immediately transmitted to the other one. A high compliance of Reissner's membrane seems to be the cause of this endolymphatic-perilymphatic pressure equalization. In experimental endolymphatic hydrops, a unique animal model for Meniere's disease, endolymphatic pressure is higher (100 Pa and above) than perilymphatic pressure. These pressure gradients occur only in late stages of hydrops, probably when Reissner's membrane has lost its high compliance after long standing distension. Positive endolymphatic-perilymphatic pressure gradients are secondary to and not the primary cause of hydrops formation. Changes of hydrostatic pressure do not affect auditory function as long as they stay in the physiological range. This includes the sudden loss of positive inner ear pressure that occurs in perilymph fistulas. The rationale for surgical repair of perilymph fistulas in patients in order to restore the hearing function thus becomes questionable. Other aspects of surgical repair, however, as e.g. prevention of labyrinthitis due to permanently open fistula, could not be investigated in this model, because in guinea pigs even large fistulas heal spontaneously within a few days. In experimental endolymphatic hydrops, deterioration of auditory thresholds was partially correlated to the presence of positive endolymphatic-perilymphatic pressure gradients. A change in pressure, however, occurred later than the first deterioration in auditory function. Therefore positive endo-perilymphatic pressure gradients may contribute to, but are not the only cause of hearing impairment. PMID:8273452

  13. Twelve oxo-eicosatetraenoic acid induces fetal membrane release after delivery in cows.

    PubMed

    Kamada, H; Matsui, Y; Sakurai, Y; Tanigawa, T; Itoh, M; Kawamoto, S; Kai, K; Sasaki, T; Takahashi, K; Hayashi, M; Takayama, Y; Nakamura, M; Kadokawa, H; Ueda, Y; Sutoh, M; Murai, M

    2012-02-01

    Fetal fibroblast cell culture from cotyledons of bovine placenta and animal experiments close to term were used to elucidate afterbirth release and factors missing in the signal transduction mechanism for retained fetal membranes (RFM) after delivery. In cell culture the addition of arachidonic acid (Ara) to the medium caused rapid release to free floating cell in the culture dish, accompanied by matrix metalloproteinase (MMP) activation, being consistent with previous invivo observations, where a relation between MMP and fetal membrane release had been shown. Ara-induced cell floating was not inhibited by the addition of cyclooxygenase (COX) inhibitor, and not induced by the addition of PGF2? or PGE2 to replace Ara, while 12-lipoxygenase (12-LOX) metabolite of Ara, 12-oxo-eicosatetraenoic acid (12-oxoETE), strongly induced cell floating. In the animal experiments, 12-oxoETE injection to delivery-induced cows (n=6) using prostaglandin (PG) and dexamethazone resulted in rapid release of fetal membranes. In cows with natural calf delivery, a 12-oxoETE peak (11.7-16.8ng/ml) was observed in maternal blood plasma prior to release of fetal membranes. This investigation thus gives new indications for that the mediator for fetal membrane release is 12-oxoETE and not PG. PMID:22118869

  14. Surgical and Technical Modalities for Hearing Restoration in Ear Malformations.

    PubMed

    Dazert, Stefan; Thomas, Jan Peter; Volkenstein, Stefan

    2015-12-01

    Malformations of the external and middle ear often go along with an aesthetic and functional handicap. Independent of additional aesthetic procedures, a successful functional hearing restoration leads to a tremendous gain in quality of life for affected patients. The introduction of implantable hearing systems (bone conduction and middle ear devices) offers new therapeutic options in this field. We focus on functional rehabilitation of patients with malformations, either by surgical reconstruction or the use of different implantable hearing devices, depending on the disease itself and the severity of malformation as well as hearing impairment. Patients with an open ear canal and minor malformations are good candidates for surgical hearing restoration of middle ear structures with passive titanium or autologous implants. In cases with complete fibrous or bony atresia of the ear canal, the most promising functional outcome and gain in quality of life can be expected with an active middle ear implant or a bone conduction device combined with a surgical aesthetic rehabilitation in a single or multi-step procedure. Although the surgical procedure for bone conduction devices is straightforward and safe, more sophisticated operations for active middle ear implants (e.g., Vibrant Soundbridge, MED-EL, Innsbruck, Austria) provide an improved speech discrimination in noise and the ability of sound localization compared with bone conduction devices where the stimulation reaches both cochleae. PMID:26667632

  15. Zwislocki's model of the middle ear re-visited

    NASA Astrophysics Data System (ADS)

    Withnell, Robert H.; Fields, Taylor N.

    2015-12-01

    Zwislocki's circuit model of the middle ear [11] has been used, in original or modified form, in subsequent studies modeling the ear [4, 6]. The model includes two eardrum modes of vibration, a shunt for flexible coupling between the incus and stapes, and a single tuned oscillator for ossicular vibration. The contribution of each of these mechanisms was examined by fitting a model of the ear to acoustic input impedance data from healthy human ears. The circuit elements for a non-ossicular eardrum vibration and a flexible coupling between the incus and stapes were found to be detrimental or non-essential for the model-fit-to-data. A single mode of eardrum vibration for sound transmission to the middle ear is consistent with the eardrum acting as an impedance-matching device, with pars-tensa eardrum vibration coupled to the ossicles [1]. A single-tuned oscillator was insufficient to account for the bandwidth of the ear. The frequency response of the ear suggests multiple resonant modes of ossicular vibration.

  16. Prenatal Ultrasound Screening for External Ear Abnormality in the Fetuses

    PubMed Central

    Wei, Jun; Ran, Suzhen; Yang, Zhengchun; Lin, Yun; Tang, Jing

    2014-01-01

    Objectives. To investigate the best time of examination and section chosen of routine prenatal ultrasound screening for external ear abnormalities and evaluate the feasibility of examining the fetal external ear with ultrasonography. Methods. From July 2010 until August 2011, 42118 pregnant women with single fetus during 16–40 weeks of pregnancy were enrolled in the study. Fetal auricles and external auditory canal in the second trimester of pregnancy were evaluated by routine color Doppler ultrasound screening and systematic screening. Ultrasound images of fetal external ears were obtained on transverse-incline view at cervical vertebra level and mandible level and on parasagittal view and coronal view at external ear level. Results. Five fetuses had anomalous ears including bilateral malformed auricles with malformed external auditory canal, unilateral deformed external ear, and unilateral microtia. The detection rate of both auricles was negatively correlated with gestational age. Of the 5843 fetuses undergoing a routine ultrasound screening, 5797 (99.21%) had bilateral auricles. Of the 4955 fetuses following systematic screening, all fetuses (100%) had bilateral auricles. The best time for fetal auricles observation with ultrasonography is 20–24 weeks of pregnancy. Conclusions. Detection of external ear abnormalities may assist in the diagnosis of chromosomal abnormalities. PMID:25050343

  17. Inverse solution of ear-canal area function from reflectance

    PubMed Central

    Rasetshwane, Daniel M.; Neely, Stephen T.

    2011-01-01

    A number of acoustical applications require the transformation of acoustical quantities, such as impedance and pressure that are measured at the entrance of the ear canal, to quantities at the eardrum. This transformation often requires knowledge of the shape of the ear canal. Previous attempts to measure ear-canal area functions were either invasive, non-reproducible, or could only measure the area function up to a point mid-way along the canal. A method to determine the area function of the ear canal from measurements of acoustic impedance at the entrance of the ear canal is described. The method is based on a solution to the inverse problem in which measurements of impedance are used to calculate reflectance, which is then used to determine the area function of the canal. The mean ear-canal area function determined using this method is similar to mean ear-canal area functions measured by other researchers using different techniques. The advantage of the proposed method over previous methods is that it is non- invasive, fast, and reproducible. PMID:22225043

  18. Fetal ear measurements in the prenatal detection of trisomy 21.

    PubMed

    Gill, P; Vanhook, J; Fitzsimmons, J; Pascoe-Mason, J; Fantel, A

    1994-08-01

    Although prominent fetal nuchal folds, short long bones, echogenic bowel, and renal pelviectasis have been shown to be associated with trisomy 21, none has acceptable diagnostic efficacy. Diminished fetal ear lengths measured by ultrasound have recently been reported as yet another potential morphological marker for the prenatal detection of trisomy 21. To investigate this further, we measured ear lengths and widths of normal (n = 107) and trisomy 21 (n = 25) second-trimester formalin-preserved fetuses. The normal ear growth characteristics are described and compared with those of trisomy 21 fetuses. The normal fetal ear shape, not unlike that of the neonates, manifested a marked variation. When the ear lengths and widths were regressed against gestational age, the slopes of the regression lines for the two groups were found to be different (P < 0.001). However, despite the statistically significant difference between the ear sizes of normal and trisomy 21 fetuses, the wide range of normal variation seen at each gestational age means that the fetal ear measurements are not diagnostically helpful. PMID:7991515

  19. 3D visualization of middle ear structures

    NASA Astrophysics Data System (ADS)

    Vogel, Uwe; Schmitt, Thomas

    1998-06-01

    The achievement of volume geometry data from middle ear structures and surrounding components performs a necessary supposition for the finite element simulation of the vibrational and transfer characteristics of the ossicular chain. So far those models base on generalized figures and size data from anatomy textbooks or particular manual and one- or two-dimensional distance measurements of single ossicles, mostly obtained by light microscopy, respectively. Therefore the goal of this study is to create a procedure for complete three-dimensional imaging of real middle ear structures (tympanic membrane, ossicles, ligaments) in vitro or even in vivo. The main problems are their microscopic size with relevant structures from 10 micrometer to 5 mm, representing various tissue properties (bone, soft tissue). Additionally, these structures are surrounded by the temporal bone, the most solid bone of the human body. Generally there exist several established diagnostic tools for medical imaging that could be used for geometry data acquisition, e.g., X-ray computed tomography and magnetic resonance imaging. Basically they image different tissue parameters, either bony structures (ossicles), or soft tissue (tympanic membrane, ligaments). But considering this application those standard techniques allow low spatial resolution only, usually in the 0.5 - 1mm range, at least in one spatial direction. Thus particular structures of the middle ear region could even be missed completely because of their spatial location. In vitro there is a way out by collecting three complete data sets, each distinguished by 90 degree rotation of a cube-shaped temporal bone specimen. That allows high-resolution imaging in three orthogonal planes, which essentially supports the three-dimensional interpolation of the unknown elements, starting from the regularly set elements of the cubic grid with an edge extension given by the original two-dimensional matrix. A different approach represents the application of a micro- tomographic imaging device. Therefore an X-ray beam focused down to few microns passes the object in a tomographic arrangement. Subsequently the slices become reconstructed. Generally spatial resolution down to 10 micrometer may be obtained by using this procedure. But there exist few devices only, it is not available as standard equipment. The best results concerning spatial resolution should be achieved by applying conventional histologic sectioning techniques. Of course the target will become destroyed during the procedure. It is cut into sections (e.g., 10 micrometer thick), every layer is stained, and the image acquired and stored by a digital still-camera with appropriate resolution (e.g., 2024 X 3036). Three-dimensional reconstruction is done with the computer. The staining allows visual selection of bones and soft tissues, resolutions down to 10 micrometer are possible without target segmentation. But there arise some practical problems. Mainly the geometric context of the layers is affected by the cutting procedure, especially if cutting bone. Another problem performs the adjustment of the -- possibly distorted -- slices to each other. Artificial markers are necessary, which could allow automatic adjustment too. But the introduction and imaging of the markers is difficult inside the temporal bone specimen, that is interspersed by several cavities. Of course the internal target structures must not be destroyed by the marker introduction. Furthermore the embedding compound could disturb the image acquisition, e.g., by optical scattering of paraffin. A related alternative is given by layered ablation/grinding and imaging of the top layer. This saves the geometric consistency, but requires very tricky and time-consuming embedding procedures. Both approaches require considerable expenditures. The possible approaches are evaluated in detail and first results are compared. So far none of the above-mentioned procedures has been established as a standard tool for three-dimensional geometry data acquisition of the middle ear. Otherwise the establishment of a high-resolution imaging technique for those structures, even in vivo, would be of high interest in diagnostics, anatomy and middle ear modeling and research at all.

  20. Human fetal inner ear involvement in congenital cytomegalovirus infection

    PubMed Central

    2013-01-01

    Background Congenital cytomegalovirus (CMV) infection is a leading cause of sensorineural hearing loss (SNHL). The mechanisms of pathogenesis of CMV-related SNHL are still unclear. The aim is to study congenital CMV-related damage in the fetal inner ear, in order to better understand the underlying pathophysiology behind CMV-SNHL. Results We studied inner ears and brains of 20 human fetuses, all at 21week gestational age, with a high viral load in the amniotic fluid, with and without ultrasound (US) brain abnormalities. We evaluated histological brain damage, inner ear infection, local inflammatory response and tissue viral load. Immunohistochemistry revealed that CMV was positive in 14/20 brains (70%) and in the inner ears of 9/20 fetuses (45%). In the cases with inner ear infection, the marginal cell layer of the stria vascularis was always infected, followed by infection in the Reissners membrane. The highest tissue viral load was observed in the inner ear with infected Organ of Corti. Vestibular labyrinth showed CMV infection of sensory cells in the utricle and in the crista ampullaris. US cerebral anomalies were detected in 6 cases, and in all those cases, the inner ear was always involved. In the other 14 cases with normal brain scan, histological brain damage was present in 8 fetuses and 3 of them presented inner ear infection. Conclusions CMV-infection of the marginal cell layer of the stria vascularis may alter potassium and ion circulation, dissipating the endocochlear potential with consequent SNHL. Although abnormal cerebral US is highly predictive of brain and inner ear damage, normal US findings cannot exclude them either. PMID:24252374

  1. Cells, molecules and morphogenesis: The making of the vertebrate ear

    PubMed Central

    Fritzsch, Bernd; Pauley, Sarah; Beisel, Kirk W.

    2014-01-01

    The development and evolution of mechanosensory cells and the vertebrate ear is reviewed with an emphasis on delineating the cellular, molecular and developmental basis of these changes. Outgroup comparisons suggests that mechanosensory cells are ancient features of multicellular organisms. Molecular evidence suggests that key genes involved in mechanosensory cell function and development are also conserved among metazoans. The divergent morphology of mechanosensory cells across phyla is interpreted here as deep molecular homology that was in parallel shaped into different forms in each lineage. The vertebrate mechanosensory hair cell and its associated neuron are interpreted as uniquely derived features of vertebrates. It is proposed that the vertebrate otic placode presents a unique embryonic adaptation in which the diffusely distributed ancestral mechanosensory cells became concentrated to generate a large neurosensory precursor population. Morphogenesis of the inner ear is reviewed and shown to depend on genes expressed in and around the hindbrain that interact with the otic placode to define boundaries and polarities. These patterning genes affect downstream genes needed to maintain proliferation and to execute ear morphogenesis. We propose that fibroblast growth factors (FGFs) and their receptors (FGFRs) are a crucial central node to translate patterning into the complex morphology of the vertebrate ear. Unfortunately, the FGF and FGFR genes have not been fully analyzed in the many mutants with morphogenetic ear defects described thus far. Likewise, little information exists on the ear histogenesis and neurogenesis in many mutants. Nevertheless, a molecular mechanism is now emerging for the formation of the horizontal canal, an evolutionary novelty of the gnathostome ear. The existing general module mediating vertical canal growth and morphogenesis was modified by two sets of new genes: one set responsible for horizontal canal morphogenesis and another set for neurosensory formation of the horizontal crista and associated sensory neurons. The dramatic progress in deciphering the molecular basis of ear morphogenesis offers grounds for optimism for translational research toward intervention in human morphogenetic defects of the ear. PMID:16643865

  2. 3D ear identification based on sparse representation.

    PubMed

    Zhang, Lin; Ding, Zhixuan; Li, Hongyu; Shen, Ying

    2014-01-01

    Biometrics based personal authentication is an effective way for automatically recognizing, with a high confidence, a person's identity. Recently, 3D ear shape has attracted tremendous interests in research field due to its richness of feature and ease of acquisition. However, the existing ICP (Iterative Closet Point)-based 3D ear matching methods prevalent in the literature are not quite efficient to cope with the one-to-many identification case. In this paper, we aim to fill this gap by proposing a novel effective fully automatic 3D ear identification system. We at first propose an accurate and efficient template-based ear detection method. By utilizing such a method, the extracted ear regions are represented in a common canonical coordinate system determined by the ear contour template, which facilitates much the following stages of feature extraction and classification. For each extracted 3D ear, a feature vector is generated as its representation by making use of a PCA-based local feature descriptor. At the stage of classification, we resort to the sparse representation based classification approach, which actually solves an l1-minimization problem. To the best of our knowledge, this is the first work introducing the sparse representation framework into the field of 3D ear identification. Extensive experiments conducted on a benchmark dataset corroborate the effectiveness and efficiency of the proposed approach. The associated Matlab source code and the evaluation results have been made publicly online available at http://sse.tongji.edu.cn/linzhang/ear/srcear/srcear.htm. PMID:24740247

  3. Subgridding method for FDTD modeling in the inner ear

    NASA Astrophysics Data System (ADS)

    Kopecky, Rudolf; Persson, Mikael

    2004-04-01

    A detailed dosimetry in the inner ear is performed using the FDTD algorithm with a subgridding method. A head model is exposed to a mobile phone radiation and the electromagnetic field in the region of the inner ear is computed with increased numerical resolution by factor of 3, 5 and 7. Results show that increase of the numerical resolution without increase of the geometrical resolution does not give more detailed SAR distribution in the inner ear. Therefore a new model of the cochlea with increasing the geometrical resolution from 1 mm to 1/7 mm and dosimetry in this model is presented.

  4. [Introduction to the surgery of the middle ear: general principles].

    PubMed

    Babighian, G; Domnguez, M J

    1993-01-01

    We study the basic guidelines of the middle ear surgery, having as target the recuperation of the anatomic functional integrity of ear. There are different important elements in the quality/quantity of the functional results as follows: The surgery technical method used. The actual pathology in the middle ear. The quality of eustachian tube function. The surgeon's experience and ability and several factors. We review the concept introduced by Wullstein called it tympanoplasty from 1952 till nowadays. Finally, we described the most frequent surgery procedures used in the daily practice. PMID:8129965

  5. Shaping sound in space: the regulation of inner ear patterning

    PubMed Central

    Groves, Andrew K.; Fekete, Donna M.

    2012-01-01

    The inner ear is one of the most morphologically elaborate tissues in vertebrates, containing a group of mechanosensitive sensory organs that mediate hearing and balance. These organs are arranged precisely in space and contain intricately patterned sensory epithelia. Here, we review recent studies of inner ear development and patterning which reveal that multiple stages of ear development – ranging from its early induction from the embryonic ectoderm to the establishment of the three cardinal axes and the fine-grained arrangement of sensory cells – are orchestrated by gradients of signaling molecules. PMID:22186725

  6. Neonatal Hairy Ear Pinnae and Gestational Diabetes: Just a Coincidence?

    PubMed

    Valerio, Enrico; Riello, Laura; Chirico, Michela; Semenzato, Rossella; Cutrone, Mario

    2015-01-01

    A newborn girl of 36 weeks gestation was noted to have several anomalies, including bilateral low ear attachment with ear pinnae hypertrichosis, left preauricular pit, micrognathia, short lingual frenulum, and short neck. Pregnancy history revealed poorly controlled maternal gestational diabetes (GD). Localized hypertrichosis of the ear pinnae may represent a potential marker of GD and thereby alert physicians to suspect other potentially GD-associated conditions such as macrosomia, asphyxia, respiratory distress, hypoglycemia, hypocalcemia, hyperbilirubinemia, polycythemia, hypertrophic cardiomyopathy, and congenital anomalies, particularly those involving the central nervous system. PMID:26391439

  7. A Case of Atypical Granuloma Annulare Involving Both Ears

    PubMed Central

    Kim, Jin Gu; Lee, Seung Hun

    2009-01-01

    We report a rare case of granuloma annulare (GA), affecting both ear antihelixes, in a 28-year old male patient that presented with a 1-year history of non-tender, firm, skin-colored, 1~5 mm papules on both ear antihelixes. There was no history of trauma. An excisional biopsy specimen taken from one of the lesions of the right ear revealed infiltration of histiocytes and lymphocytes around a zone of collagen alteration in the dermis. Based on the clinical and pathological findings, the patient was diagnosed with a rare case of bilateral GA of both antihelixes; this is the first report in the Korean dermatology literature. PMID:20523836

  8. Acute effects of irradiation on middle ear mucosa

    SciTech Connect

    Ohashi, Y.; Nakai, Y.; Esaki, Y.; Ikeoka, H.; Koshimo, H.; Onoyama, Y.

    1988-03-01

    Single field, fixed irradiation of bilateral tympanic cavities using 200-kV x-rays was administered to five guinea pigs. The irradiation dose was 30 Gy. They were killed immediately after irradiation, and bilateral middle ear mucosa was examined for ciliary activity and epithelial structure. Significant deterioration of the ciliary activity in the middle ear mucosa was observed, proximal as well as distal to the eustachian tube. Electron microscopy showed various changes in the irradiated middle ear mucosa. The most conspicuous findings were hyperreactivity in secretion, vacuolation of ciliated cells, and stomal edema.

  9. Evolution of Gravity Receptors in the Ear

    NASA Technical Reports Server (NTRS)

    Popper, Arthur N. (Principal Investigator)

    1996-01-01

    The general status of a grant to investigate the origins and evolution of two hair cell types in the ears of a teleost fish, Astronotus ocellatus (the oscar), is presented. First, it was demonstrated that the cells in the rostral end of the saccule of the , Carassius auratus, are type 1-like, while those at the caudal end are type 2 cells. It was demonstrated that the dichotomy of hair cell types found in the utricle of the oscar is also found in the goldfish. Second, the lateral line system of the oscar was examined using gentamicin sulphate, an ototocix drug that destroys type 1- like hair cells but does not appear to damage type 2 hair cells. It was demonstrated that the hair cells found in neuromasts of lateral line canal organs were totally destroyed within 1 day of treatment, while the hair cells in free neuromasts were undamaged after 12 days of treatment. Third, it was demonstrated that the calyx, the specialized nerve ending, is not unique to amniotes and that it is present at least in the cristae of semicirular canals in goldfish. These results have demonstrated that: (1) there are multiple hair cell types in the vestibular endorgans of the ear of fishes, (2) these hair cell types are very similar to those found in the mammalian vestibular endorgans, (3) the nerve calyx is also present in fishes, and (4) multiple hair cell types and the calyx have evolved far earlier in the course of vertebrate evolution than heretofore thought. Understanding the structure of the vestibular endorgans has important implications for being able to understand how these organs respond to gravistatic, acceleration and acoustic input. The vestibular endorgans of fishes may provide an ideal system in which to analyze functional differences in hair cells. Not only are the two hair cell types similar to those found in mammals, they are located in very discrete regions in each endorgan. Thus, it is relatively easy to gain access to cells of one or the other type. The presence of two cell types in the lateral line have equally significant implications for studies of the vestibular system.

  10. 2-Hydroxy Arachidonic Acid: A New Non-Steroidal Anti-Inflammatory Drug

    PubMed Central

    Lopez, Daniel H.; Fiol-deRoque, Maria A.; Noguera-Salv, Maria A.; Ters, Silvia; Campana, Federica; Piotto, Stefano; Castro, Jos A.; Mohaibes, Raheem J.; Escrib, Pablo V.; Busquets, Xavier

    2013-01-01

    Background Nonsteroidal anti-inflammatory drugs (NSAIDs) are a family of COX1 and COX2 inhibitors used to reduce the synthesis of pro-inflammatory mediators. In addition, inflammation often leads to a harmful generation of nitric oxide. Efforts are being done in discovering safer NSAIDs molecules capable of inhibiting the synthesis of pro-inflammatory lipid mediators and nitric oxide to reduce the side effects associated with long term therapies. Methodology/Principal Findings The analogue of arachidonic acid (AA), 2-hydroxy-arachidonic acid (2OAA), was designed to inhibit the activities of COX1 and COX2 and it was predicted to have similar binding energies as AA for the catalytic sites of COX1 and COX2. The interaction of AA and 2OAA with COX1 and COX2 was investigated calculating the free energy of binding and the Fukui function. Toxicity was determined in mouse microglial BV-2 cells. COX1 and COX2 (PGH2 production) activities were measured in vitro. COX1 and COX2 expression in human macrophage-like U937 cells were carried out by Western blot, immunocytochemistry and RT-PCR analysis. NO production (Griess method) and iNOS (Western blot) were determined in mouse microglial BV-2 cells. The comparative efficacy of 2OAA, ibuprofen and cortisone in lowering TNF-? serum levels was determined in C57BL6/J mice challenged with LPS. We show that the presence of the OH group reduces the likelihood of 2OAA being subjected to H* abstraction in COX, without altering significantly the free energy of binding. The 2OAA inhibited COX1 and COX2 activities and the expression of COX2 in human U937 derived macrophages challenged with LPS. In addition, 2OAA inhibited iNOS expression and the production of NO in BV-2 microglial cells. Finally, oral administration of 2OAA decreased the plasma TNF-? levels in vivo. Conclusion/Significance These findings demonstrate the potential of 2OAA as a NSAID. PMID:24015204

  11. DIBROMOACETIC ACID-INDUCED ELEVATIONS IN CIRCULATING ESTRADIOL: EFFECTS IN BOTH CYCLING AND OVARIECTOMIZED/STEROID-PRIMED FEMALE RATS

    EPA Science Inventory

    RTD-03-031
    Goldman, JM and Murr, AS. Dibromoacetic Acid-induced Elevations in Circulating Estradiol: Effects in Both Cycling and Ovariectomized/Steroid-primed Female Rats. Reproductive Toxicology (in press).

    Abstract

    Oral exposures to high concentrations of th...

  12. DIBROMOACETIC ACID-INDUCED ELEVATIONS OF ESTRADIOL IN THE CYCLING AND OVARIECTOMOZED/ESTRADIOL-IMPLANTED FEMALE RAT

    EPA Science Inventory

    Goldman, JM and Murr, AS. Dibromoacetic Acid-induced Elevations of Estradiol in Both Cycling and Ovariectomized / Estradiol-implanted Female Rats

    ABSTRACT
    Haloacetic acids are one of the principal classes of disinfection by-products generated by the chlorination of mun...

  13. Effect of p-bromophenacyl bromide, an inhibitor of phospholipase A2, on arachidonic acid release and prostaglandin synthesis by the guinea-pig uterus in vitro.

    PubMed Central

    Mitchell, S; Poyser, N L; Wilson, N H

    1977-01-01

    The synthesis of prostaglandins F2alpha and E2 by guinea-pig uterine homogenates was inhibited by p-bromophenacyl bromide (PBPAB), an inhibitor of phospholipase A2. 2 Metabolism of prostaglandin F2alpha by uterine homogenates was undetectable; this was not affected by PBPAB. 3 There was no significant difference between the amounts of arachidonic acid released from uterine homogenates on days 7 and 1k of the oestrous cycle. Small amounts of dihomo-gamma-linolenic acid were detected in the homogenates. 4 The release of arachidonic acid from uterine homogenates was greatly inhibited by PBPAB. 5 Addition of exogenous arachidonic acid to uterine homogenates did not overcome the inhibition of uterine prostaglandin F2alpha synthesis produced by PBPAB. 6 It is concluded that PBPAB inhibits both the release of arachidonic acid from the guinea-pig uterus and its subsequent conversion into prostaglandins. PMID:836991

  14. Extract of a spice--omum (Trachyspermum ammi)-shows antiaggregatory effects and alters arachidonic acid metabolism in human platelets.

    PubMed

    Srivastava, K C

    1988-07-01

    An ethereal extract of omum (Trachyspermum ammi; Hindustani: ajwan)--a frequently consumed spice--was found to inhibit platelet aggregation induced by arachidonic acid (AA), epinephrine and collagen; in this respect it was most effective against AA-induced aggregation. Inhibition of aggregation by omum could be explained by its effect on platelet thromboxane production as suggested by the following experimental observation. (i) Omum reduced TxB2 formation in intact platelet preparations from added arachidonate, and (ii) it reduced the formation of TxB2 from AA-labelled platelets after stimulation with Ca2+-ionophore A23187 by a direct action on cyclooxygenase as it did not affect the release of AA from labelled platelets. An increased formation of lipoxygenase-derived products from exogenous AA in omum-treated platelets was apparently due to redirection of AA from cyclooxygenase to the lipoxygenase pathway. PMID:3141935

  15. Laser vibrometer measurements and middle ear prostheses

    NASA Astrophysics Data System (ADS)

    Flock, Stephen T.; Dornhoffer, John; Ferguson, Scott

    1997-05-01

    One of us has developed an improved partial ossicular replacement prosthesis that is easier to implant and, based on pilot clinical measurements, results in better high-frequency hearing as compared to patients receiving one of the alternative prostheses. It is hypothesized that the primary reason for this is because of the relatively light weight (about 25 mg) and low compliance of the prosthesis, which could conceivably result in better high frequency vibrational characteristics. The purpose of our initial work was to develop an instrument suitable for objectively testing the vibrational characteristics of prostheses. We have developed a laser based device suitable for measuring the vibrational characteristics of the oval window or other structures of the middle ear. We have tested this device using a piezoelectric transducer excited at audio frequencies, as well as on the oval window in human temporal bones harvested from cadavers. The results illustrate that it is possible to non-invasively monitor the vibrational characteristics of anatomic structures with a very inexpensive photonic device.

  16. Image analysis of the human inner ear.

    PubMed

    Kubo, T; Anniko, M; Hsu, W J

    1998-01-01

    The KS 300 is a multifunctional software image analysis system using an object-oriented programming environment. The possibility of its application for the inner ear was studied by using specimens from humans and squirrel monkeys, immunostained for the brain-derived calcium-binding protein, S-100 protein. Grey images were used for measurements. The cell borders were outlined by hand, using a digitizer. The absolute grey values of the pixels changed when the brightness of the images or other conditions changed. By contrast, the relative grey values, i.e. the absolute grey values correlated to the mean grey values of the histoimage, remained constant. By utilizing these relative grey values, it was possible to compare cells both between different specimens and between different areas within the same specimen. The different grey values of spiral ganglion cells stained for S-100 protein are objective quantitative measurements and are believed to reflect differences in their function. In some regions of both human and squirrel monkey specimens, relatively intensely stained cells predominated, whereas in other regions, relatively weakly stained cells were mainly observed. Thus, our image analysis system using the relative grey values has proved suitable for quantitative analysis of immunostained specimens in order to compare them and to assess cell function. PMID:9504164

  17. Changes in bacteriology of discharging ears.

    PubMed

    Hwang, Juen-Haur; Chu, Chih-Kai; Liu, Tien-Chen

    2002-09-01

    A bacteriological study on 161 consecutive out-patients presenting with otorrhoea was performed prospectively at a local teaching hospital in Taiwan between August 2000 and June 2001. A total of 177 isolates were recovered. Staphylococcus aureus was found in 77 (43.5 per cent) isolates, and non-Staphylococcus aureus in 100 (56.5 per cent) isolates. Pseudomas sp was found to be the most common pathogen (28.8 per cent) in the non-Staphylococcus aureus group. Staphylococcus aureus had become more common than Pseudomonas aeruginosa in acute otitis externa, granular myringitis, and chronic otitis media in Taiwan. Methicillin-resistant Staphylococcus aureus (MRSA) was also an increasing problem in all three disease entities. The prevalence of community-acquired MRSA infections in discharging ears was found to be 13.7 per cent (22/161). MRSAs were highly susceptible to vancomycin, teicoplanin, fusidic acid, and minocycline. More studies should be done to determine the susceptibility of MRSA to ofloxacin in the future. PMID:12437801

  18. Why Internally Coupled Ears (ICE) Work Well

    NASA Astrophysics Data System (ADS)

    van Hemmen, J. Leo

    2014-03-01

    Many vertebrates, such as frogs and lizards, have an air-filled cavity between left and right eardrum, i.e., internally coupled ears (ICE). Depending on source direction, internal time (iTD) and level (iLD) difference as experienced by the animal's auditory system may greatly exceed [C. Vossen et al., JASA 128 (2010) 909-918] the external, or interaural, time and level difference (ITD and ILD). Sensory processing only encodes iTD and iLD. We present an extension of ICE theory so as to elucidate the underlying physics. First, the membrane properties of the eardrum explain why for low frequencies iTD dominates whereas iLD does so for higher frequencies. Second, the plateau of iTD = ? ITD for constant 1 < ? < 5 and variable input frequency

  19. Green laser light activates the inner ear

    NASA Astrophysics Data System (ADS)

    Wenzel, Gentiana I.; Balster, Sven; Zhang, Kaiyin; Lim, Hubert H.; Reich, Uta; Massow, Ole; Lubatschowski, Holger; Ertmer, Wolfgang; Lenarz, Thomas; Reuter, Guenter

    2009-07-01

    The hearing performance with conventional hearing aids and cochlear implants is dramatically reduced in noisy environments and for sounds more complex than speech (e. g. music), partially due to the lack of localized sensorineural activation across different frequency regions with these devices. Laser light can be focused in a controlled manner and may provide more localized activation of the inner ear, the cochlea. We sought to assess whether visible light with parameters that could induce an optoacoustic effect (532 nm, 10-ns pulses) would activate the cochlea. Auditory brainstem responses (ABRs) were recorded preoperatively in anesthetized guinea pigs to confirm normal hearing. After opening the bulla, a 50-μm core-diameter optical fiber was positioned in the round window niche and directed toward the basilar membrane. Optically induced ABRs (OABRs), similar in shape to those of acoustic stimulation, were elicited with single pulses. The OABR peaks increased with energy level (0.6 to 23 μJ/pulse) and remained consistent even after 30 minutes of continuous stimulation at 13 μJ, indicating minimal or no stimulation-induced damage within the cochlea. Our findings demonstrate that visible light can effectively and reliably activate the cochlea without any apparent damage. Further studies are in progress to investigate the frequency-specific nature and mechanism of green light cochlear activation.

  20. Groovy flow patterns in the fish ear

    NASA Astrophysics Data System (ADS)

    Kotas, Charlotte W.; Rogers, Peter H.; Yoda, Minami

    2007-11-01

    The dense, bony otoliths contained in the fish ear oscillate with respect to their surrounding tissue and endolymph in the presence of sound waves. How an otolith actually transduces this acoustically induced fluid motion into the hair cell displacements that the fish ``hears'' is not fully understood, however. The fluid flow created by the oscillation of the irregularly shaped otolith has both steady and unsteady components. Since most of the hair cells are next to a grooved area on the otolith, the sulcus, the otolith was modeled as a grooved spheroid oscillating in a quiescent Newtonian fluid. Particle-image velocimetry and pathline visualizations for the steady streaming flows within the groove are presented for oscillation at 0 --90 with respect to the body axis of symmetry Re=2?f,^2/?=O(10-10^2), and ?=s/L 0.025-0.05. Here, ? is the fluid kinematic viscosity, L is a typical length based on the spheroid, and f and s are the oscillation frequency and amplitude, respectively. Results for bodies oscillated by multiple frequencies f1 and f2 along the same direction imply that the velocity fields are the superposition of those due to the component frequencies for small values of ?.

  1. Blackbody for metrological control of ear thermometers

    NASA Astrophysics Data System (ADS)

    Crdenas-Garca, D.; Mndez-Lango, E.

    2013-09-01

    Body temperature is an important parameter in medical practice, and most of health diagnoses are made based upon measured temperature values. Non-contact measurements are attractive to both patients and physicians, and ear thermometers (ET) are part of the set of infrared thermometers for medical applications. ETs sense the tympanic membrane temperature which best represents body temperature. They take advantage of the natural high effective emissivity cavity that is formed as radiation source. To calibrate or to check the performance of ETs, we designed a high-emissivity spherical cavity as a blackbody source which can be placed in a dry block oven. Although the blackbody cavity can have any shape, we decided to build it spherical because its effective emissivity can be easily calculated in a closed form. The cavity is made of Aluminum to take advantage of its high thermal conductivity while its inner side is covered with a black paint to increase the cavity effective emissivity. Based on paint emissivity measurements and the geometrical shape, we calculated that the cavity has an effective emissivity higher than 0.999. Blackbody temperature is measured with a calibrated contact thermometer placed inside the bottom wall of the cavity. We present the design of the cavity, the experimental setup, and results of three commercial ETs compared with this cavity.

  2. Molecular dynamics simulations of arachidonic acid complexes with COX-1 and COX-2: insights into equilibrium behavior.

    PubMed

    Furse, Kristina E; Pratt, Derek A; Porter, Ned A; Lybrand, Terry P

    2006-03-14

    The cyclooxygenase (COX) enzymes are responsible for the committed step in prostaglandin biosynthesis, the generation of prostaglandin H(2). As a result, these enzymes are pharmacologically important targets for nonsteroidal antiinflammatory drugs, such as aspirin and newer COX-2 selective inhibitors. The cyclooxygenases are functional homodimers, and each subunit contains both a cyclooxygenase and a peroxidase active site. These enzymes are quite interesting mechanistically, as the conversion of arachidonic acid to prostaglandin H(2) requires two oxygenation and two cyclization reactions, resulting in the formation of five new chiral centers with nearly absolute regio- and stereochemical fidelity. We have used molecular dynamics (MD) simulations to investigate the equilibrium behavior of both COX-1 and COX-2 enzyme isoforms with bound arachidonate. These simulations were compared with reference simulations of arachidonate in solution to explore the effect of enzyme on substrate conformation and positioning in the active site. The simulations suggest that the substrate has greater conformational freedom in the COX-2 active site, consistent with the larger COX-2 active site volume observed in X-ray crystal structures. The simulations reveal different conformational behavior for arachidonate in each subunit over the course of extended equilibrium MD simulations. The simulations also provide detailed information for several protein channels that might be important for oxygen and water transport to or from active sites or for intermediate trafficking between the cyclooxygenase and peroxidase active sites. The detailed comparisons for COX-1 versus COX-2 active site structural fluctuations may also provide useful information for design of new isozyme-selective inhibitors. PMID:16519514

  3. Peroxisome-proliferator-activated receptors and the control of levels of prostaglandin-endoperoxide synthase 2 by arachidonic acid in the bovine uterus

    PubMed Central

    Sheldrick, E.LindaR.; Derecka, Kamila; Marshall, Elaine; Chin, EvonneC.; Hodges, Louise; Wathes, D.Claire; Abayasekara, D.RobertE.; Flint, AnthonyP.F.

    2007-01-01

    Arachidonic acid is a potential paracrine agent released by the uterine endometrial epithelium to induce PTGS2 [PG (prostaglandin)-endoperoxide synthase 2] in the stroma. In the present study, bovine endometrial stromal cells were used to determine whether PTGS2 is induced by arachidonic acid in stromal cells, and to investigate the potential role of PPARs (peroxisome-proliferator-activated receptors) in this effect. Arachidonic acid increased PTGS2 levels up to 7.5-fold within 6h. The cells expressed PPAR? and PPAR? (also known as PPAR?) (but not PPAR?). PTGS2 protein level was increased by PPAR agonists, including polyunsaturated fatty acids, synthetic PPAR ligands, PGA1 and NSAIDs (non-steroidal anti-inflammatory drugs) with a time course resembling that of arachidonic acid. Use of agonists and antagonists indicated PPAR? (but not PPAR? or PPAR?) was responsible for PTGS2 induction. PTGS2 induction by arachidonic acid did not require PG synthesis. PTGS2 levels were increased by the PKC (protein kinase C) activators 4?-PMA and PGF2?, and the effects of arachidonic acid, NSAIDs, synthetic PPAR ligands and 4?-PMA were blocked by PKC inhibitors. This is consistent with PPAR phosphorylation by PKC. Induction of PTGS2 protein by 4?-PMA in the absence of a PPAR ligand was decreased by the NF-?B (nuclear factor ?B) inhibitors MG132 and parthenolide, suggesting that PKC acted through NF-?B in addition to PPAR phosphorylation. Use of NF-?B inhibitors allowed the action of arachidonic acid as a PPAR agonist to be dissociated from an effect through PKC. The results are consistent with the hypothesis that arachidonic acid acts via PPAR? to increase PTGS2 levels in bovine endometrial stromal cells. PMID:17516915

  4. Making an Effort to Listen: Mechanical Amplification in the Ear

    PubMed Central

    Hudspeth, A. J.

    2009-01-01

    The inner ears performance is greatly enhanced by an active process defined by four features: amplification, frequency selectivity, compressive nonlinearity, and spontaneous otoacoustic emission. These characteristics emerge naturally if the mechanoelectrical transduction process operates near a dynamical instability, the Hopf bifurcation, whose mathematical properties account for specific aspects of our hearing. The active process of non-mammalian tetrapods depends upon active hair-bundle motility, which emerges from the interaction of negative hair-bundle stiffness and myosin-based adaptation motors. Taken together, these phenomena explain the four characteristics of the ears active process. In the high-frequency region of the mammalian cochlea, the active process is dominated instead by the phenomenon of electromotility, in which the cell bodies of outer hair cells extend and contract as the protein prestin alters its membrane surface area in response to changes in membrane potential. PMID:18760690

  5. How minute sooglossid frogs hear without a middle ear.

    PubMed

    Boistel, Renaud; Aubin, Thierry; Cloetens, Peter; Peyrin, Franoise; Scotti, Thierry; Herzog, Philippe; Gerlach, Justin; Pollet, Nicolas; Aubry, Jean-Franois

    2013-09-17

    Acoustic communication is widespread in animals. According to the sensory drive hypothesis [Endler JA (1993) Philos Trans R Soc Lond B Biol Sci 340(1292):215-225], communication signals and perceptual systems have coevolved. A clear illustration of this is the evolution of the tetrapod middle ear, adapted to life on land. Here we report the discovery of a bone conduction-mediated stimulation of the ear by wave propagation in Sechellophryne gardineri, one of the world's smallest terrestrial tetrapods, which lacks a middle ear yet produces acoustic signals. Based on X-ray synchrotron holotomography, we measured the biomechanical properties of the otic tissues and modeled the acoustic propagation. Our models show how bone conduction enhanced by the resonating role of the mouth allows these seemingly deaf frogs to communicate effectively without a middle ear. PMID:24003145

  6. How minute sooglossid frogs hear without a middle ear

    PubMed Central

    Boistel, Renaud; Aubin, Thierry; Cloetens, Peter; Peyrin, Françoise; Scotti, Thierry; Herzog, Philippe; Gerlach, Justin; Pollet, Nicolas; Aubry, Jean-François

    2013-01-01

    Acoustic communication is widespread in animals. According to the sensory drive hypothesis [Endler JA (1993) Philos Trans R Soc Lond B Biol Sci 340(1292):215–225], communication signals and perceptual systems have coevolved. A clear illustration of this is the evolution of the tetrapod middle ear, adapted to life on land. Here we report the discovery of a bone conduction–mediated stimulation of the ear by wave propagation in Sechellophryne gardineri, one of the world’s smallest terrestrial tetrapods, which lacks a middle ear yet produces acoustic signals. Based on X-ray synchrotron holotomography, we measured the biomechanical properties of the otic tissues and modeled the acoustic propagation. Our models show how bone conduction enhanced by the resonating role of the mouth allows these seemingly deaf frogs to communicate effectively without a middle ear. PMID:24003145

  7. Ensemble training to improve recognition using 2D ear

    NASA Astrophysics Data System (ADS)

    Middendorff, Christopher; Bowyer, Kevin W.

    2009-05-01

    The ear has gained popularity as a biometric feature due to the robustness of the shape over time and across emotional expression. Popular methods of ear biometrics analyze the ear as a whole, leaving these methods vulnerable to error due to occlusion. Many researchers explore ear recognition using an ensemble, but none present a method for designing the individual parts that comprise the ensemble. In this work, we introduce a method of modifying the ensemble shapes to improve performance. We determine how different properties of an ensemble training system can affect overall performance. We show that ensembles built from small parts will outperform ensembles built with larger parts, and that incorporating a large number of parts improves the performance of the ensemble.

  8. Tympanostomy Tubes: A Rational Clinical Treatment for Middle Ear Disease.

    ERIC Educational Resources Information Center

    Roland, Peter S.; Brown, Orval

    1990-01-01

    The use of tympanostomy tubes to treat middle ear disease including otitis media is discussed with sections on the eustachian tube; acute otitis media; persistent effusion; changes in the tympanic membrane; special populations; and complications. (DB)

  9. Carnosic Acid Induces Apoptosis Through Reactive Oxygen Species-mediated Endoplasmic Reticulum Stress Induction in Human Renal Carcinoma Caki Cells

    PubMed Central

    Min, Kyoung-jin; Jung, Kyong-Jin; Kwon, Taeg Kyu

    2014-01-01

    Background: Carnosic acid, which is one of extract components of rosemary, has anti-inflammatory, anti-oxidant, and anti-cancer effects. However, the anti-cancer effect of carnosic acid in human renal carcinoma cells is unknown. Methods: Flow cytometry analysis was used to examine the effects of carnosic acid on apoptosis, and Asp-Glu-Val-Asp-ase activity assay kit was used to investigate the involvement of caspase activation. To determine protein expression of apoptotic and endoplasmic reticulum (ER) stress-related proteins, we used Western blotting. Intracellular accumulation of reactive oxygen species (ROS) was determined using the fluorescent probes 2, 7-dichlorodihydrofluorescein diacetate (H2DCFDA). Results: Carnosic acid induced sub-diploid DNA content, sub-G1, population and poly (ADP-ribose) polymerase (PARP) cleavage and activated caspase-3. A pan-caspase inhibitor, a benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone, markedly reduced apoptosis in carnosic acid-treated cells. Carnosic acid promoted intracellular ROS production, and pretreatment with the ROS scavengers (N-acetyl-L-cysteine and glutathione ethyl ester) inhibited carnosic acid-induced apoptosis. Furthermore, carnosic acid also induced expression of ER stress marker proteins, including activating transcription factor 4 (ATF4) and CCAAT/enhancer-binding protein-homologous protein (CHOP), in a dose- and time-dependent manner. Down-regulation of ATF4 and CHOP by small interfering RNA (siRNA) markedly reduced carnosic acid-induced sub-G1 population and PARP cleavage. In addition, carnosic acid induced apoptosis in human breast carcinoma MDA-MB-361 and human hepatocellular carcinoma SK-HEP1 cells, but not in normal human skin fibroblast cells and normal mouse kidney epithelial TMCK-1 cells. Conclusion: Carnosic acid induced apoptosis through production of ROS and induction of ER stress in human renal carcinoma Caki cells. PMID:25337586

  10. Rho Kinase ROCK2 Mediates Acid-Induced NADPH Oxidase NOX5-S Expression in Human Esophageal Adenocarcinoma Cells

    PubMed Central

    Cao, Weibiao

    2016-01-01

    Mechanisms of the progression from Barrett’s esophagus (BE) to esophageal adenocarcinoma (EA) are not fully understood. We have shown that NOX5-S may be involved in this progression. However, how acid upregulates NOX5-S is not well known. We found that acid-induced increase in NOX5-S expression was significantly decreased by the Rho kinase (ROCK) inhibitor Y27632 in BE mucosal biopsies and FLO-1 EA cells. In addition, acid treatment significantly increased the Rho kinase activity in FLO-1 cells. The acid-induced increase in NOX5-S expression and H2O2 production was significantly decreased by knockdown of Rho kinase ROCK2, but not by knockdown of ROCK1. Conversely, the overexpression of the constitutively active ROCK2, but not the constitutively active ROCK1, significantly enhanced the NOX5-S expression and H2O2 production. Moreover, the acid-induced increase in Rho kinase activity and in NOX5-S mRNA expression was blocked by the removal of calcium in both FLO-1 and OE33 cells. The calcium ionophore A23187 significantly increased the Rho kinase activity and NOX5-S mRNA expression. We conclude that acid-induced increase in NOX5-S expression and H2O2 production may depend on the activation of ROCK2, but not ROCK1, in EA cells. The acid-induced activation of Rho kinase may be mediated by the intracellular calcium increase. It is possible that persistent acid reflux present in BE patients may increase the intracellular calcium, activate ROCK2 and thereby upregulate NOX5-S. High levels of reactive oxygen species derived from NOX5-S may cause DNA damage and thereby contribute to the progression from BE to EA. PMID:26901778

  11. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  12. 21 CFR 874.4420 - Ear, nose, and throat manual surgical instrument.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat manual surgical instrument... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4420 Ear, nose, and throat manual surgical instrument. (a) Identification. An ear, nose, and throat manual...

  13. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat drug administration device... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose, and throat drug administration device. (a) Identification. An ear, nose, and throat...

  14. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat synthetic polymer material... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3620 Ear, nose, and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic...

  15. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat drug administration device... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose, and throat drug administration device. (a) Identification. An ear, nose, and throat...

  16. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat synthetic polymer material... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3620 Ear, nose, and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic...

  17. 21 CFR 874.4350 - Ear, nose, and throat fiberoptic light source and carrier.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat fiberoptic light source and... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4350 Ear, nose, and throat fiberoptic light source and carrier. (a) Identification. An ear, nose, and...

  18. 21 CFR 874.4350 - Ear, nose, and throat fiberoptic light source and carrier.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat fiberoptic light source and... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4350 Ear, nose, and throat fiberoptic light source and carrier. (a) Identification. An ear, nose, and...

  19. 21 CFR 874.4350 - Ear, nose, and throat fiberoptic light source and carrier.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat fiberoptic light source and... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4350 Ear, nose, and throat fiberoptic light source and carrier. (a) Identification. An ear, nose, and...

  20. 21 CFR 874.4420 - Ear, nose, and throat manual surgical instrument.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat manual surgical instrument... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4420 Ear, nose, and throat manual surgical instrument. (a) Identification. An ear, nose, and throat manual...

  1. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat microsurgical carbon dioxide... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4500 Ear, nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and...

  2. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  3. 15 CFR 732.2 - Steps regarding scope of the EAR.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 2 2011-01-01 2011-01-01 false Steps regarding scope of the EAR. 732... FOR USING THE EAR § 732.2 Steps regarding scope of the EAR. Steps 1 though 6 are designed to aid you in determining the scope of the EAR. A flow chart describing these steps is contained in...

  4. 21 CFR 874.4350 - Ear, nose, and throat fiberoptic light source and carrier.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat fiberoptic light source and... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4350 Ear, nose, and throat fiberoptic light source and carrier. (a) Identification. An ear, nose, and...

  5. 21 CFR 874.4420 - Ear, nose, and throat manual surgical instrument.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat manual surgical instrument... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4420 Ear, nose, and throat manual surgical instrument. (a) Identification. An ear, nose, and throat manual...

  6. 21 CFR 874.4250 - Ear, nose, and throat electric or pneumatic surgical drill.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat electric or pneumatic... AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4250 Ear, nose, and throat electric or pneumatic surgical drill. (a) Identification. An ear, nose,...

  7. 21 CFR 874.4250 - Ear, nose, and throat electric or pneumatic surgical drill.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat electric or pneumatic... AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4250 Ear, nose, and throat electric or pneumatic surgical drill. (a) Identification. An ear, nose,...

  8. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat synthetic polymer material... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3620 Ear, nose, and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic...

  9. 15 CFR 732.2 - Steps regarding scope of the EAR.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 2 2010-01-01 2010-01-01 false Steps regarding scope of the EAR. 732... FOR USING THE EAR § 732.2 Steps regarding scope of the EAR. Steps 1 though 6 are designed to aid you in determining the scope of the EAR. A flow chart describing these steps is contained in...

  10. 21 CFR 874.4250 - Ear, nose, and throat electric or pneumatic surgical drill.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat electric or pneumatic... AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4250 Ear, nose, and throat electric or pneumatic surgical drill. (a) Identification. An ear, nose,...

  11. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  12. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat microsurgical carbon dioxide... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4500 Ear, nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and...

  13. 21 CFR 874.4250 - Ear, nose, and throat electric or pneumatic surgical drill.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat electric or pneumatic... AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4250 Ear, nose, and throat electric or pneumatic surgical drill. (a) Identification. An ear, nose,...

  14. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat microsurgical carbon dioxide... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4500 Ear, nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and...

  15. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  16. 21 CFR 874.4350 - Ear, nose, and throat fiberoptic light source and carrier.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat fiberoptic light source and... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4350 Ear, nose, and throat fiberoptic light source and carrier. (a) Identification. An ear, nose, and...

  17. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat examination and treatment... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5300 Ear, nose, and throat examination and treatment unit. (a) Identification. An ear, nose, and...

  18. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat synthetic polymer material... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3620 Ear, nose, and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic...

  19. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat drug administration device... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose, and throat drug administration device. (a) Identification. An ear, nose, and throat...

  20. 21 CFR 874.4250 - Ear, nose, and throat electric or pneumatic surgical drill.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat electric or pneumatic... AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4250 Ear, nose, and throat electric or pneumatic surgical drill. (a) Identification. An ear, nose,...

  1. 21 CFR 874.4420 - Ear, nose, and throat manual surgical instrument.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Ear, nose, and throat manual surgical instrument... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4420 Ear, nose, and throat manual surgical instrument. (a) Identification. An ear, nose, and throat manual...

  2. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat microsurgical carbon dioxide... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4500 Ear, nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and...

  3. 21 CFR 874.3620 - Ear, nose, and throat synthetic polymer material.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat synthetic polymer material... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3620 Ear, nose, and throat synthetic polymer material. (a) Identification. Ear, nose, and throat synthetic...

  4. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat drug administration device... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose, and throat drug administration device. (a) Identification. An ear, nose, and throat...

  5. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Ear, nose, and throat microsurgical carbon dioxide... HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4500 Ear, nose, and throat microsurgical carbon dioxide laser. (a) Identification. An ear, nose, and...

  6. 21 CFR 874.4420 - Ear, nose, and throat manual surgical instrument.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat manual surgical instrument... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4420 Ear, nose, and throat manual surgical instrument. (a) Identification. An ear, nose, and throat manual...

  7. 21 CFR 874.5220 - Ear, nose, and throat drug administration device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Ear, nose, and throat drug administration device... SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Therapeutic Devices § 874.5220 Ear, nose, and throat drug administration device. (a) Identification. An ear, nose, and throat...

  8. Sonographic Measurement of Fetal Ear Length in Turkish Women with a Normal Pregnancy

    PubMed Central

    zdemir, Mucize Eri; Uzun, I??l; Karahasano?lu, Ay?e; Aygn, Mehmet; Ak?n, Hale; Yaz?c?o?lu, Fehmi

    2014-01-01

    Background: Abnormal fetal ear length is a feature of chromosomal disorders. Fetal ear length measurement is a simple measurement that can be obtained during ultrasonographic examinations. Aims: To develop a nomogram for fetal ear length measurements in our population and investigate the correlation between fetal ear length, gestational age, and other standard fetal biometric measurements. Study Design: Cohort study. Methods: Ear lengths of the fetuses were measured in normal singleton pregnancies. The relationship between gestational age and fetal ear length in millimetres was analysed by simple linear regression. In addition, the correlation of fetal ear length measurements with biparietal diameter, head circumference, abdominal circumference, and femur length were evaluated.Ear length measurements were obtained from fetuses in 389 normal singleton pregnancies ranging between 16 and 28 weeks of gestation. Results: A nomogram was developed by linear regression analysis of the parameters ear length and gestational age. Fetal ear length (mm) = y = (1.348 X gestational age)?12.265), where gestational ages is in weeks. A high correlation was found between fetal ear length and gestational age, and a significant correlation was also found between fetal ear length and the biparietal diameter (r=0.962; p<0.001). Similar correlations were found between fetal ear length and head circumference, and fetal ear length and femur length. Conclusion: The results of this study provide a nomogram for fetal ear length. The study also demonstrates the relationship between ear length and other biometric measurements. PMID:25667783

  9. Arachidonate 5 Lipoxygenase Expression in Papillary Thyroid Carcinoma Promotes Invasion via MMP-9 Induction

    PubMed Central

    Kummer, Nicolas T.; Nowicki, Theodore S; Azzi, Jean Paul; Reyes, Ismael; Iacob, Codrin; Xie, Suqing; Swati, Ismatun; Suslina, Nina; Schantz, Stimson; Tiwari, Raj K.; Geliebter, Jan

    2012-01-01

    Arachidonate 5-lipoxygenase (ALOX5) expression and activity has been implicated in tumor pathogenesis, yet its role in papillary thyroid carcinoma (PTC) has not been characterized. ALOX5 protein and mRNA were upregulated in PTC compared to matched, normal thyroid tissue, and ALOX5 expression correlated with invasive tumor histopathology. Evidence suggests that PTC invasion is mediated through the induction of matrix metalloproteinases (MMPs) that can degrade and remodel the extracellular matrix (ECM). A correlation between MMP-9 and ALOX5 protein expression was established by immunohistochemical analysis of PTC and normal thyroid tissues using a tissue array. Transfection of ALOX5 into a PTC cell line (BCPAP) increased MMP-9 secretion and cell invasion across an ECM barrier. The ALOX5 product, 5(S)-hydroxyeicosatetraenoic acid also increased MMP-9 protein expression by BCPAP in a dose-dependent manner. Inhibitors of MMP-9 and ALOX5 reversed ALOX5-enhanced invasion. Here we describe a new role for ALOX5 as a mediator of invasion via MMP-9 induction; this ALOX5/MMP9 pathway represents a new avenue in the search for functional biomarkers and/or potential therapeutic targets for aggressive PTC. PMID:22253131

  10. What is the relationship between gestational age and docosahexaenoic acid (DHA) and arachidonic acid (ARA) levels?

    PubMed

    Baack, Michelle L; Puumala, Susan E; Messier, Stephen E; Pritchett, Deborah K; Harris, William S

    2015-09-01

    Long chain polyunsaturated fatty acids (LCPUFA) including docosahexaenoic acid (DHA) and arachidonic acid (ARA) are increasingly transferred from mother to fetus late in pregnancy. Infants born before this transfer is complete are at risk for deficiency. This study determines the relationship between gestational age (GA) and circulating LCPUFA levels to better understand the unique needs of premature infants born at various GAs. Whole blood was collected within the first 7 days of life from 60 preterm (≤34 weeks GA) and 30 term infants (≥38 weeks GA) and FA levels were analyzed. Since concurrent intravenous lipid emulsion can skew composition data, blood LCPUFA concentrations were also measured. Levels were compared among groups, and linear regression models were used to examine the association between FA composition and GA. Preterm infants had significantly lower DHA and ARA levels than term peers, and whether assessed as concentrations or compositions, both directly correlated with GA (p<0.0001). Moreover, FA comparisons suggest that premature infants have impaired synthesis of LCPUFAs from precursors and may require preformed DHA and ARA. This study confirms that essential FA status is strongly related to GA, and that those babies born the earliest are at the greatest risk of LCPUFA deficiency. PMID:26205427

  11. Epoxygenase metabolites of arachidonic acid inhibit vasopressin response in toad bladder

    SciTech Connect

    Schlondorff, D.; Petty, E.; Oates, J.A.; Jacoby, M.; Levine, S.D. Vanderbilt Univ., Nashville, TN )

    1987-09-01

    In addition to cyclooxygenase and lipoxygenase pathways, the kidney can also metabolize arachidonic acid by a NADPH-dependent cytochrome P-450 enzyme to epoxyeicosatrienoic acids (EETs); furthermore, 5,6-EET has been shown to alter electrolyte transport across isolated renal tubules. The authors examined the effects of three ({sup 14}C-labeled)-EETs (5,6-, 11,12-, and 14,15-EET) on osmotic water flow across toad urinary bladder. All three EETs reversibly inhibited vasopressin-stimulated osmotic water flow with 5,6- and 11,12-EET being the most potent. The effects appeared to be independent of prostaglandins EETs inhibited the water flow response to forskolin but not the response to adenosine 3{prime},5{prime}-cyclic monophosphate (cAMP) or 8-BrcAMP, consistent with an effect on cAMP generation. To determine whether these effects were due to the EETs or to products of their metabolism, they examined the effects of their vicinal diol hydrolysis products, the dihydroxyeicosatrienoic acids. Nonenzymatic conversion of labeled 5,6-EET to its vicinal diol occurred rapidly in the buffer, whereas 11,12-EET was hydrolyzed in a saturable manner only when incubated in the presence of bladder tissue. The dihydroxyeicosatrienoic acids formed inhibited water flow in a manner paralleling that of the EETs. The data support the hypothesis that EETs and their physiologically active dihydroxyeicosatrienoic acid metabolites inhibit vasopressin-stimulated water flow predominantly via inhibition of adenylate cyclase.

  12. Dual regulation of ?-opioid receptor function by arachidonic acid metabolites in rat peripheral sensory neurons.

    PubMed

    Sullivan, Laura C; Berg, Kelly A; Clarke, William P

    2015-04-01

    The regulation of opioid receptor system function in peripheral sensory neurons is not well understood. Opioid agonist efficacy to inhibit nociceptor function and to promote antinociception is generally weak under basal conditions and frequently no response occurs. However, in response to a cyclooxygenase-dependent metabolite of arachidonic acid (AA) after exposure to inflammatory mediators, such as bradykinin (BK) or exogenous AA, peripheral opioid receptor systems become much more responsive to opioid agonists. In this study, we examined the time course for the induction and maintenance of functional competence of the ?-opioid receptor (DOR) system in adult rat nociceptors in culture and in vivo. We found that the responsive state of DOR after pretreatment with BK or exogenous AA is transient (30-60 minutes) and persists for 15-30 minutes after a 15-minute exposure of nociceptors to BK or AA. Interestingly, whereas functional competence of the DOR system could be reinduced with a second application of BK 60 minutes after the first, responsiveness of the DOR system could not be reinduced after an initial exposure to AA. This nonresponsive state of DOR after exogenous AA was mediated by a lipoxygenase (LOX)-dependent metabolite of AA. Intraplantar carrageenan also produced transient DOR functional competence and responsiveness was also reinduced by inhibition of LOX. Thus, the DOR system expressed by peripheral sensory neurons is under dual regulation by cyclooxygenase- and LOX-dependent metabolites of AA. PMID:25637601

  13. Oral gold compound auranofin triggers arachidonate release and cyclooxygenase metabolism in the alveolar macrophage

    SciTech Connect

    Peters-Golden, M.; Shelly, C.

    1988-12-01

    We examined the effect of in vitro incubation with the oral gold compound auranofin (AF) on arachidonic acid (AA) release and metabolism by rat alveolar macrophages (AMs). AF stimulated dose- and time-dependent release of /sup 14/C-AA from prelabeled AMs, which reached 4.7 +/- 0.3% (mean +/- SEM) of incorporated radioactivity at 10 micrograms/ml for 90 min, as compared to 0.5 +/- 0.1% release following control incubation for 90 min (p less than 0.001). Similar dose- and time-dependent synthesis of thromboxane (Tx) A2 (measured as TxB2) and prostaglandin (PG) E2 was demonstrated by radioimmunoassay of medium from unlabeled cultures, reaching 18-fold and 9-fold, respectively, of the control values at 10 micrograms/ml AF for 90 min (p less than 0.001 for both). AF-induced TxB2 and PGE2 synthesis was inhibited by indomethacin as well as by pretreatment with methylprednisolone. No increase in the synthesis of immunoreactive leukotrienes (LT) B4 or C4 was noted at any dose or time of AF. High performance liquid chromatographic separation of /sup 14/C-eicosanoids synthesized by prelabeled AMs confirmed that AF induced the release of free AA and its metabolism to cyclooxygenase, but not 5-lipoxygenase, metabolites. The ability of AF to trigger macrophage AA metabolism may be relevant to the exacerbation of certain inflammatory processes which sometimes accompany gold therapy.

  14. Visible light-sensitized oxidation of arachidonic acid in the presence of inperatorin.

    PubMed

    Fukui, Y; Morita, M; Osakada, K; Nakayama, T; Matsuoka, M; Hirota, R; Iizumi, H; Ueda, T

    1995-06-01

    To understand the mechanism of the phototoxic effects of inperatorin, a psoralen derivative used as a pigmentation agent, we have investigated the photosensitized oxidation of arachidonic acid (ARA) by irradiation with visible light (> 400 nm) in the presence of inperatorin. HPLC and GC/MS analyses of the products showed the formation of many hydroperoxyeicosatetraenoic acids (HPETEs) including the products of lipoxygenase-catalyzed reactions such as 5- and 15-HPETEs, which are the precursors of chemical mediators such as leukotrienes and lipoxins, during the reaction. Active oxygen scavening agents such as D-mannitol, superoxide dismutase, and beta-carotene inhibited the formation of the oxidation products, indicating that the oxidation reaction was mediated by various active oxygen species. These results suggest that the phototoxic effects of inperatorin could also be induced by visible light and could be explained at least partially in terms of inflammation initiated by the biologically active HPETEs arising from photosensitized oxygenation reactions of ARA with the drug. PMID:7472682

  15. IMAGING BRAIN SIGNAL TRANSDUCTION AND METABOLISM VIA ARACHIDONIC AND DOCOSAHEXAENOIC ACID IN ANIMALS AND HUMANS

    PubMed Central

    Basselin, Mireille; Ramadan, Epolia; Rapoport, Stanley I.

    2012-01-01

    The polyunsaturated fatty acids (PUFAs), arachidonic acid (AA, 20:4n-6) and docosahexaenoic acid (DHA, 22:6n-3), important second messengers in brain, are released from membrane phospholipid following receptor-mediated activation of specific phospholipase A2 (PLA2) enzymes. We developed an in vivo method in rodents using quantitative autoradiography to image PUFA incorporation into brain from plasma, and showed that their incorporation rates equal their rates of metabolic consumption by brain. Thus, quantitative imaging of unesterified plasma AA or DHA incorporation into brain can be used as a biomarker of brain PUFA metabolism and neurotransmission. We have employed our method to image and quantify effects of mood stabilizers on brain AA/DHA incorporation during neurotransmission by muscarinic M1,3,5, serotonergic 5-HT2A/2C, dopaminergic D2-like (D2, D3, D4) or glutamatergic N-methyl-D-aspartic acid (NMDA) receptors, and effects of inhibition of acetylcholinesterase, of selective serotonin and dopamine reuptake transporter inhibitors, of neuroinflammation (HIV-1 and lipopolysaccharide) and excitotoxicity, and in genetically modified rodents. The method has been extended for the use with positron emission tomography (PET), and can be employed to determine how human brain AA/DHA signaling and consumption are influenced by diet, aging, disease and genetics. PMID:22178644

  16. LPIAT1 regulates arachidonic acid content in phosphatidylinositol and is required for cortical lamination in mice

    PubMed Central

    Lee, Hyeon-Cheol; Inoue, Takao; Sasaki, Junko; Kubo, Takuya; Matsuda, Shinji; Nakasaki, Yasuko; Hattori, Mitsuharu; Tanaka, Fumiharu; Udagawa, Osamu; Kono, Nozomu; Itoh, Toshiki; Ogiso, Hideo; Taguchi, Ryo; Arita, Makoto; Sasaki, Takehiko; Arai, Hiroyuki

    2012-01-01

    Dietary arachidonic acid (AA) has roles in growth, neuronal development, and cognitive function in infants. AA is remarkably enriched in phosphatidylinositol (PI), an important constituent of biological membranes in mammals; however, the physiological significance of AA-containing PI remains unknown. In an RNA interferencebased genetic screen using Caenorhabditis elegans, we recently cloned mboa-7 as an acyltransferase that selectively incorporates AA into PI. Here we show that lysophosphatidylinositol acyltransferase 1 (LPIAT1, also known as MBOAT7), the closest mammalian homologue, plays a crucial role in brain development in mice. Lpiat1?/? mice show almost no LPIAT activity with arachidonoyl-CoA as an acyl donor and show reduced AA contents in PI and PI phosphates. Lpiat1?/? mice die within a month and show atrophy of the cerebral cortex and hippocampus. Immunohistochemical analysis reveals disordered cortical lamination and delayed neuronal migration in the cortex of E18.5 Lpiat1?/? mice. LPIAT1 deficiency also causes disordered neuronal processes in the cortex and reduced neurite outgrowth in vitro. Taken together, these results demonstrate that AA-containing PI/PI phosphates play an important role in normal cortical lamination during brain development in mice. PMID:23097495

  17. Pharmacological manipulation of arachidonic acid-epoxygenase results in divergent effects on renal damage

    PubMed Central

    Li, Jing; Stier, Charles T.; Chander, Praveen N.; Manthati, Vijay L.; Falck, John R.; Carroll, Mairad A.

    2014-01-01

    Kidney damage is markedly accelerated by high-salt (HS) intake in stroke-prone spontaneously hypertensive rats (SHRSP). Epoxyeicosatrienoic acids (EETs) are epoxygenase products of arachidonic acid which possess vasodepressor, natriuretic, and anti-inflammatory activities. We examined whether up-regulation (clofibrate) or inhibition [N-methylsulfonyl-6-(2-propargyloxyphenyl)hexanamide (MS-PPOH)] of epoxygenase would alter systolic blood pressure (SBP) and/or renal pathology in SHRSP on HS intake (1% NaCl drinking solution). Three weeks of treatment with clofibrate induced renal cortical protein expression of CYP2C23 and increased urinary excretion of EETs compared with vehicle-treated SHRSP. SBP and urinary protein excretion (UPE) were significantly lowered with clofibrate treatment. Kidneys from vehicle-treated SHRSP, which were on HS intake for 3 weeks, demonstrated focal lesions of vascular fibrinoid degeneration, which were markedly attenuated with clofibrate treatment. In contrast, 2 weeks of treatment with the selective epoxygenase inhibitor, MS-PPOH, increased UPE without significantly altering neither urinary EET levels nor SBP. Kidneys from vehicle-treated SHRSP, which were on HS intake for 11 days, demonstrated occasional mild damage whereas kidneys from MS-PPOH-treated rats exhibited widespread malignant nephrosclerosis. These results suggest that pharmacological manipulation of epoxygenase results in divergent effects on renal damage and that interventions to increase EET levels may provide therapeutic strategies for treating salt-sensitive hypertension and renal damage. PMID:25177296

  18. Chronic lithium feeding reduces upregulated brain arachidonic acid metabolism in HIV-1 transgenic rat.

    PubMed

    Ramadan, Epolia; Basselin, Mireille; Chang, Lisa; Chen, Mei; Ma, Kaizong; Rapoport, Stanley I

    2012-09-01

    HIV-1 transgenic (Tg) rats, a model for human HIV-1 associated neurocognitive disorder (HAND), show upregulated markers of brain arachidonic acid (AA) metabolism with neuroinflammation after 7months of age. Since lithium decreases AA metabolism in a rat lipopolysaccharide model of neuroinflammation, and may be useful in HAND, we hypothesized that lithium would dampen upregulated brain AA metabolism in HIV-1 Tg rats. Regional brain AA incorporation coefficients k* and rates J ( in ), markers of AA signaling and metabolism, were measured in 81 brain regions using quantitative autoradiography, after intravenous [1-(14)?C]AA infusion in unanesthetized 10-month-old HIV-1 Tg and age-matched wildtype rats that had been fed a control or LiCl diet for 6weeks. k* and J ( in ) for AA were significantly higher in HIV-1 Tg than wildtype rats fed the control diet. Lithium feeding reduced plasma unesterified AA concentration in both groups and J ( in ) in wildtype rats, and blocked increments in k* (19 of 54 regions) and J ( in ) (77 of 81 regions) in HIV-1 Tg rats. These in vivo neuroimaging data indicate that lithium treatment dampened upregulated brain AA metabolism in HIV-1 Tg rats. Lithium may improve cognitive dysfunction and be neuroprotective in HIV-1 patients with HAND through a comparable effect. PMID:22760927

  19. Arachidonate release and prostaglandin production by group IVC phospholipase A2 (cytosolic phospholipase A2gamma).

    PubMed Central

    Murakami, Makoto; Masuda, Seiko; Kudo, Ichiro

    2003-01-01

    While the role of the group IVA Ca(2+)-dependent cytosolic phospholipase A(2)alpha (cPLA(2)alpha) in arachidonic acid (AA) metabolism has been well documented, that of its paralogue, Ca(2+)-independent group IVC PLA(2) (cPLA(2)gamma), has remained uncertain. Here we show, using a transfection strategy, that cPLA(2)gamma has the ability to increase the spontaneous and stimulus-induced release of cellular fatty acids. The AA released by cPLA(2)gamma was metabolized further to prostaglandin E(2) via cyclo-oxygenase-1 (COX-1) in the immediate response, and via COX-2 in the delayed response. Mutation of the putative catalytic-centre residue Ser(82) abrogated the AA-releasing function of cPLA(2)gamma both in vitro and in vivo. Confocal microscopy revealed that cPLA(2)gamma was distributed in the perinuclear endoplasmic reticulum membranes. Mutating the C-terminal prenylation site of cPLA(2)gamma abrogated its intracellular membrane localization and cellular AA-releasing function, without reducing its enzyme activity in vitro. Our results indicate that cPLA(2)gamma is the second cPLA(2) enzyme that contributes to cellular AA metabolism and phospholipid remodelling under appropriate conditions. PMID:12611587

  20. Arachidonate 5 lipoxygenase expression in papillary thyroid carcinoma promotes invasion via MMP-9 induction.

    PubMed

    Kummer, Nicolas T; Nowicki, Theodore S; Azzi, Jean P; Reyes, Ismael; Iacob, Codrin; Xie, Suqing; Swati, Ismatun; Darzynkiewicz, Zbigniew; Gotlinger, Katherine H; Suslina, Nina; Schantz, Stimson; Tiwari, Raj K; Geliebter, Jan

    2012-06-01

    Arachidonate 5-lipoxygenase (ALOX5) expression and activity has been implicated in tumor pathogenesis, yet its role in papillary thyroid carcinoma (PTC) has not been characterized. ALOX5 protein and mRNA were upregulated in PTC compared to matched, normal thyroid tissue, and ALOX5 expression correlated with invasive tumor histopathology. Evidence suggests that PTC invasion is mediated through the induction of matrix metalloproteinases (MMPs) that can degrade and remodel the extracellular matrix (ECM). A correlation between MMP-9 and ALOX5 protein expression was established by immunohistochemical analysis of PTC and normal thyroid tissues using a tissue array. Transfection of ALOX5 into a PTC cell line (BCPAP) increased MMP-9 secretion and cell invasion across an ECM barrier. The ALOX5 product, 5(S)-hydroxyeicosatetraenoic acid also increased MMP-9 protein expression by BCPAP in a dose-dependent manner. Inhibitors of MMP-9 and ALOX5 reversed ALOX5-enhanced invasion. Here we describe a new role for ALOX5 as a mediator of invasion via MMP-9 induction; this ALOX5/MMP9 pathway represents a new avenue in the search for functional biomarkers and/or potential therapeutic targets for aggressive PTC. PMID:22253131

  1. Associations between a fatty acid desaturase gene polymorphism and blood arachidonic acid compositions in Japanese elderly.

    PubMed

    Horiguchi, Sayaka; Nakayama, Kazuhiro; Iwamoto, Sadahiko; Ishijima, Akiko; Minezaki, Takayuki; Baba, Mamiko; Kontai, Yoshiko; Horikawa, Chika; Kawashima, Hiroshi; Shibata, Hiroshi; Kagawa, Yasuo; Kawabata, Terue

    2016-02-01

    We investigated whether the single nucleotide polymorphism rs174547 (T/C) of the fatty acid desaturase-1 gene, FADS1, is associated with changes in erythrocyte membrane and plasma phospholipid (PL) long-chain polyunsaturated fatty acid (LCPUFA) composition in elderly Japanese participants (n=124; 65 years or older; self-feeding and oral intake). The rs174547 C-allele carriers had significantly lower arachidonic acid (ARA; n-6 PUFA) and higher linoleic acid (LA, n-6 PUFA precursor) levels in erythrocyte membrane and plasma PL (15% and 6% ARA reduction, respectively, per C-allele), suggesting a low LA to ARA conversion rate in erythrocyte membrane and plasma PL of C-allele carriers. α-linolenic acid (n-3 PUFA precursor) levels were higher in the plasma PL of C-allele carriers, whereas levels of the n-3 LCPUFAs eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) were unchanged in erythrocyte membrane and plasma PL. Thus, rs174547 genotypes were significantly associated with different ARA compositions of the blood of elderly Japanese. PMID:26869086

  2. Characterization of arachidonate 5-lipoxygenase and leukotriene A4 synthetase from RBL-1 cells

    SciTech Connect

    Cook, M.; Hogaboom, G.K.; Sarau, H.M.; Foley, J.J.; Crooke, S.T.

    1986-05-01

    5-lipoxygenase (LO) and leukotriene (LT) A4 synthetase from RBL-1 high speed (105,000 x g for 60 min) supernatants were partially purified by protein-high performance liquid chromatography (HPLC) and characterized in detail. The partially purified preparation contained only 5-LO and LTA4 synthetase and was isolated from 12-LO, peroxidase and LTA4 hydrolase activities. Reaction products were separated by reversed phase HPLC and quantitated by absorption spectrophotometry and radiochemical detection. The enzyme preparation rapidly converted (/sup 14/C)arachidonate to (/sup 14/C)5-hydroperoxyeicosatetraenoic acid (HPETE) and (/sup 14/C)5,12-dihydroperoxyeicosatetraenoic acids (diHETEs). The 5,12-diHETEs were primarily non-enzymatic breakdown products of LTA4 (e.g., 6-trans-LTB4 and 6-trans-12-epi-LTB4). Both the 5-LO and LTA4 synthetase activities were Ca/sup 2 + -/ and ATP-dependent. For both enzyme activities, the CA/sup 2 +/ stimulation required the presence of ATP. The fatty acid hydroperoxides, 5-,12-, and 15-HPETE, both stimulated ((< 1 ..mu..M)) and inhibited ((> 3 ..mu..M)) 5-LO and LTA4 synthetase activities. The rapid isolation and subsequent characterization of 5-LO and LTA4 synthetase provide the bases for the further understanding of the role of the LO pathway in biological processes.

  3. The effect of trinitrobenzene sulfonic acid (TNB) on colonocyte arachidonic acid metabolism.

    PubMed

    Stratton, M D; Sexe, R; Peterson, B; Kaminski, D L; Li, A P; Longo, W E

    1996-02-01

    In previous studies we found that luminal perfusion of the isolated left colon of the rabbit with the hapten, trinitrobenzene, resulted in the production of an acute inflammatory process associated with alterations in eicosanoid metabolism. As the colitis was attenuated by cyclooxygenase inhibitors it is possible that the inflammation was mediated by arachidonic acid metabolites. In the present study it was intended to evaluate the effect of trinitrobenzene on eicosanoid metabolism in transformed human colonic cells by exposing Caco-2++ cells to various doses of trinitrobenzene. Cell injury was evaluated by measuring lactate dehydrogenase levels and cyclooxygenase and lipoxygenase activity was evaluated by measuring prostanoid and leukotriene production. In separate experiments resting and trinitrobenzene stimulated cells were treated with indomethacin and dexamethasone. Trinitrobenzene produced increased prostaglandin E2 and 6-keto prostaglandin F1alpha++ and increased lactate dehydrogenase levels. Leukotriene B4 was significantly increased compared to control values at the highest TNB concentration administered. Indomethacin inhibited the lactate dehydrogenase and prostanoid changes, suggesting that the inflammatory changes produced were mediated by the prostanoids. Dexamethasone administered for 1 hr prior to trinitrobenzene decreased the 6-keto prostaglandin F1alpha but did not alter trinitrobenzene produced changes in lactate dehydrogenase concentrations. Exposure of Caco-2 cells to dexamethasone for 24 hr decreased the trinitrobenzene produced lactate dehydrogenase and eicosanoid changes. The results suggest that trinitrobenzene produces an acute injury to Caco-2 cells that may be mediated by the cyclooxygenase enzymes. PMID:8598672

  4. Effects of Angiotensin II Receptor Blockers on Metabolism of Arachidonic Acid via CYP2C8.

    PubMed

    Senda, Asuna; Mukai, Yuji; Toda, Takaki; Hayakawa, Toru; Yamashita, Miki; Eliasson, Erik; Rane, Anders; Inotsume, Nobuo

    2015-01-01

    Arachidonic acid (AA) is metabolized to epoxyeicosatrienoic acids (EETs) via cytochrome enzymes such as CYP 2C9, 2C8 and 2J2. EETs play a role in cardioprotection and regulation of blood pressure. Recently, adverse reactions such as sudden heart attack and fatal myocardial infarction were reported among patients taking angiotensin II receptor blockers (ARBs). As some ARBs have affinity for these CYP enzymes, metabolic inhibition of AA by ARBs is a possible cause for the increase in cardiovascular events. In this study, we quantitatively investigated the inhibitory effects of ARBs on the formation of EETs and further metabolites, dihydroxyeicosatrienoic acids (DHETs), from AA via CYP2C8. In incubations with recombinant CYP2C8 in vitro, the inhibitory effects were compared by measuring EETs and DHETs by HPLC-MS/MS. Inhibition of AA metabolism by ARBs was detected in a concentration-dependent manner with IC50 values of losartan (42.7?M), telmisartan (49.5?M), irbesartan (55.6?M), olmesartan (66.2?M), candesartan (108?M), and valsartan (279?M). Losartan, telmisartan and irbesartan, which reportedly accumulate in the liver and kidneys, have stronger inhibitory effects than other ARBs. The lower concentration of EETs leads to less protective action on the cardiovascular system and a higher incidence of adverse effects such as sudden heart attack and myocardial infarction in patients taking ARBs. PMID:26632190

  5. Effect of heavy metal ions on neutrophil arachidonic acid metabolism and chemotaxis

    SciTech Connect

    Smith, D.M.; Turner, S.R.; Johnson, J.A.; Turner, R.A.

    1986-05-01

    Heavy metal ions can inhibit arachidonic acid (AA) metabolism, protect against ionophore cytotoxicity (ibid) and inhibit neutrophil chemotaxis. In this study they used Au/sup +3/, Zn/sup +2/, Cr/sup +3/, Mn/sup +2/, and Cu/sup +2/ as probes of the interrelationships among AA metabolism, ionophore-mediated cytotoxicity, and chemotaxis. Phospholipid deacylation was measured in ionophore-treated cells prelabeled with /sup 3/H-AA. Eicosanoid release from ionophore-treated cells was monitored both qualitatively by thin-layer chromatography of /sup 3/H-AA metabolities and quantitatively by radioimmunoassay. Cytoprotection was quantitated as ability to exclude trypan blue. Chemotaxis toward f-Met-Leu-Phe was measured by leading front analysis. The results imply that metal ions attenuate ionophore cytotoxicity by blocking phospholipid deacylation and eicosanoid production. In contrast to previous reports, the data obtained using Au/sup +3/ and Cu/sup +2/ demonstrates no correlation between AA metabolism and chemotaxis, suggesting that these 2 processes are not linked.

  6. Arachidonic acid status correlates with first year growth in preterm infants.

    PubMed Central

    Carlson, S E; Werkman, S H; Peeples, J M; Cooke, R J; Tolley, E A

    1993-01-01

    Diets deficient in the omega-6 fatty acid linoleic acid reduce arachidonic acid (Ach) concentrations and retard growth of developing animals and humans. Nevertheless, plasma phosphatidylcholine Ach concentrations declined from 84 +/- 23 mg/liter at birth to a nadir of 38 +/- 11 mg/liter at 4 mo of age in preterm infants fed commercial formulas with linoleic acid, and weight normalized to that of term infants fell progressively beginning at 2 mo of age. The nadir of plasma phosphatidylcholine Ach (31 +/- 7 mg/liter) and growth were further reduced by formula containing marine oil compared with the commercial formulas. Ach status (defined as the mean plasma phosphatidylcholine Ach concentration at 2, 4, and 6.5 mo) correlated with one or more measures of normalized growth through 12 mo. Ach status and maternal height accounted for as much as 59% of the weight variance and 68% of the length variance in infants fed standard formulas. Better Ach status was not from higher energy intakes. A conditional Ach deficiency in preterm infants may contribute to growth over the first year of life. On the strength of the relationship between Ach status and growth, we hypothesize that dietary Ach could improve first year growth of preterm infants. PMID:8430076

  7. Chronic administration of valproic acid reduces brain NMDA signaling via arachidonic acid in unanesthetized rats

    PubMed Central

    Basselin, Mireille; Chang, Lisa; Chen, Mei; Bell, Jane M.; Rapoport, Stanley I.

    2008-01-01

    Evidence that brain glutamatergic activity is pathologically elevated in bipolar disorder suggests that mood stabilizers are therapeutic in the disease in part by downregulating glutamatergic activity. Such activity can involve the second messenger, arachidonic acid (AA, 20:4n-6). We tested this hypothesis with regard to valproic acid (VPA), when stimulating glutamatergic N-methyl-D-aspartate (NMDA) receptors in rat brain and measuring AA and related responses. An acute subconvulsant dose of NMDA (25 mg/kg i.p.) or saline was administered to unanesthetized rats that had been treated i.p. daily with VPA (200 mg/kg) or vehicle for 30 days. Quantitative autoradiography following intravenous [1-14C]AA infusion was used to image regional brain AA incorporation coefficients k*, markers of AA signaling. In chronic vehicle-pretreated rats, NMDA compared with saline significantly increased k* in 41 of 82 examined brain regions, many of which have high NMDA receptor densities, and also increased brain concentrations of the AA metabolites, prostaglandin E2 (PGE2) and thromboxane B2 (TXB2). VPA pretreatment reduced baseline concentrations of PGE2 and TXB2, and blocked the NMDA induced increases in k* and in eicosanoid concentrations. These results, taken with evidence that carbamazepine and lithium also block k* responses to NMDA in rat brain, suggest that mood stabilizers act in bipolar disorder in part by downregulating glutamatergic signaling involving AA. PMID:18461450

  8. Arachidonic acid attenuates learning and memory dysfunction induced by repeated isoflurane anesthesia in rats

    PubMed Central

    Li, Chunjiang; Wang, Qingwei; Li, Lanlan; Liu, Yun; Diao, Hongwei

    2015-01-01

    This study aims to explore the effects of arachidonic acid (ARA) on learning and memory dysfunction in rats exposed to repeated isoflurane anesthesia and the underlying mechanisms. Fifty rats were randomly divided into five groups: sham control group, isoflurane group, low dose ARA + isoflurane group, moderate dose ARA + isoflurane group, high dose ARA + isoflurane group. The Morris water maze test was performed to assess learning and memory function and the hippocampus tissues were obtained for biochemical analysis. The results showed that administration of ARA improved learning and memory deficit induced by repeated isofluane anesthesia in Morris water maze test and in a dose-dependent manner. Additionally, ARA increased the activities of choline acetyl transferase (ChAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and the levels of acetycholine (Ach) and ?-amino-butyric acid (GABA), whereas decreased the activity of acetylcholine esterase (AchE), the content of glutamate (Glu) and malondialdehyde (MDA), and the radio of Glu/GABA. Meanwhile, ARA elevated the ratio of Bcl-2/Bax and inhibited the activity of caspase-3. In conclusion, ARA has potential therapeutic value in alleviating isoflurane-induced learning and memory impairment. The mechanism might be involved in regulating the cholinergic and Glu/GABA regulatory system, decreasing oxidative damage and inhibiting cell apoptosis. PMID:26550146

  9. Arachidonate 5-lipoxygenase (ALOX5) gene polymorphism is associated with Alzheimer's disease and body mass index.

    PubMed

    Šerý, Omar; Hlinecká, Lýdia; Povová, Jana; Bonczek, Ondřej; Zeman, Tomáš; Janout, Vladimír; Ambroz, Petr; Khan, Naim A; Balcar, Vladimir J

    2016-03-15

    Dementias of old age, in particular Alzheimer's disease (AD), pose a growing threat to the longevity and quality of life of individuals as well as whole societies world-wide. The risk factors are both genetic and environmental (life-style) and there is an overlap with similar factors predisposing to cardiovascular diseases (CVD). Using a case-control genetic approach, we have identified a SNP (rs10507391) in ALOX5 gene, previously associated with an increased risk of stroke, as a novel genetic risk factor for AD. ALOX5 gene encodes a 5'-lipoxygenase (5'-LO) activating protein (FLAP), a crucial component of the arachidonic acid/leukotriene inflammatory cascade. A-allele of rs4769874 polymorphism increases the risk of AD 1.41-fold (p<0.0001), while AA genotype does so 1.79-fold (p<0.0001). In addition, GG genotype of rs4769874 polymorphism is associated with a modest increase in body mass index (BMI). We discuss potential biochemical mechanisms linking the SNP to AD and suggest possible preventive pharmacotherapies some of which are based on commonly available natural products. Finally, we set the newly identified AD risk factors into a broader context of similar CVD risk factors to generate a more comprehensive picture of interacting genetics and life-style habits potentially leading to the deteriorating mental health in the old age. PMID:26944113

  10. Altered macrophage arachidonic acid metabolism induced by endotoxin tolerance: characterization and mechanisms

    SciTech Connect

    Rogers, T.S.

    1986-01-01

    Altered macrophage arachidonic acid (AA) metabolism may play a role in endotoxic shock and the phenomenon of endotoxin tolerance induced by repeated injections of endotoxin. Studies were initiated to characterize both lipoxygenase and cyclooxygenase metabolite formation by endotoxin tolerant and non-tolerant macrophages in response to 4 different stimuli, i.e., endotoxin, glucan, zymosan, and the calcium ionophore A23187. In contrast to previous reports of decreased prostaglandin synthesis by tolerant macrophages, A23187-stimulated immunoreactive (i) leukotriene (LT) C/sub 4/D/sub 4/ and prostaglandin (PG) E/sub 2/ production by tolerant cells was greater than that by non-tolerant controls (p <0.001). However, A23187-stimulated i6-keto PGF/sub 1a/ levels were lower in tolerant macrophages compared to controls (P < 0.05). iL TC/sub 4/D/sub 4/ production was not significantly stimulated by endotoxin or glucan, but was stimulated by zymosan in non-tolerant cells. Synthesis of iLTB/sub 4/ by control macrophages was stimulated by endotoxin (p <0.01). The effect of tolerance on factors that affect AA release was investigated by measuring /sup 14/C-AA incorporation and release and phospholipase A/sub 2/ activity

  11. Arachidonic acid-rich oil production by Mortierella alpina with different gas distributors.

    PubMed

    Nie, Zhi-Kui; Ji, Xiao-Jun; Shang, Jing-Sheng; Zhang, Ai-Hui; Ren, Lu-Jing; Huang, He

    2014-06-01

    Arachidonic acid (ARA)-rich oil production by Mortierella alpina is a high oxygen demand and shear-sensitive process. In the aerobic fermentation process, oxygen supply is usually a limiting factor owing to the low solubility of oxygen in the fermentation broth. Two kinds of perforated ring gas distributors and a novel microporous ceramic membrane gas distributor were designed and applied to improve oxygen supply. With the decrease of the orifice diameter of perforated ring gas distributors, dry cell weight (DCW), lipids concentration, and ARA content in total fatty acid increased from 17.86 g/L, 7.08 g/L, and 28.08 % to 25.67 g/L, 11.94 g/L, and 36.99 %, respectively. Furthermore, the effect of different dissolved oxygen (DO) on ARA-rich oil production with membrane gas distributor was also studied. The maximum DCW, lipid concentration, and ARA content using membrane gas distributor with DO controlled at 40 % reached 29.67 g/L, 16.74 g/L, and 49.53 %, respectively. The ARA titer increased from 1.99 to 8.29 g/L using the membrane gas distributor to substitute the perforated ring gas distributor. In the further experiment, a novel tubular titanium metal membrane gas distributor was successfully applied in a 7,000 L bioreactor and the results demonstrated that membrane gas distributor was industrially practical. PMID:24374968

  12. Regulation of connexin36 gap junction channels by n-alkanols and arachidonic acid

    PubMed Central

    Marandykina, Alina; Palacios-Prado, Nicols; Rimkut?, Lina; Skeberdis, Vytenis A; Bukauskas, Feliksas F

    2013-01-01

    We examined junctional conductance (gj) and its dependence on transjunctional voltage in gap junction (GJ) channels formed of wild-type connexin36 (Cx36) or its fusion form with green fluorescent protein (Cx36-EGFP) transfected in HeLa cells or endogenously expressed in primary culture of pancreatic ?-cells. Only a very small fraction (?0.8%) of Cx36-EGFP channels assembled into junctional plaques of GJs were open under control conditions. We found that short carbon chain n-alkanols (SCCAs) increased gj, while long carbon chain n-alkanols resulted in full uncoupling; cutoff is between heptanol and octanol. The fraction of functional channels and gj increased several fold under an exposure to SCCAs, or during reduction of endogenous levels of arachidonic acid (AA) by exposure to fatty acid-free BSA or cytosolic phospholipase A2 inhibitors. Moreover, uncoupling caused by exogenously applied AA can be rescued by BSA, which binds AA and other polyunsaturated fatty acids (PUFAs), but not by BSA modified with 1,2-cyclohexanedione, which does not bind AA and other PUFAs. We propose that under control conditions, Cx36 GJ channels in HeLa transfectants and ?-cells are inhibited by endogenous AA, which stabilizes a closed conformational state of the channel that leads to extremely low fraction of functional channels. In addition, SCCAs increase gj by interfering with endogenous AA-dependent inhibition, increasing open probability and the fraction of functional channels. PMID:23420660

  13. Calcium-dependent phospholipid catabolism and arachidonic acid mobilization in cerebral minces

    SciTech Connect

    Damron, D.S.; Dorman, R.V. )

    1990-06-01

    Cerebral minces were used to investigate the role of calcium influx on trauma-induced alterations of brain lipid metabolism. Cerebral phospholipids, nonpolar lipids, and free fatty acids were radiolabeled in vivo with ({sup 3}H)arachidonic acid. Tissue incubation stimulated the time-dependent catabolism of choline and inositol glycerophospholipids, and resulted in the accumulation of ({sup 3}H)free fatty acids. These effects were attenuated in Ca{sup 2}{sup +}-free incubations, and when EGTA or verapamil were present. The inhibition of calcium influx also reduced the labeling of diglycerides, whereas ethanolamine and serine glycerophospholipids were not affected by incubation or treatments. Replacing Ca{sup 2}{sup +} with other cations also attenuated the incubation-dependent alterations in lipid metabolism. However, only cadmium was able to compete with calcium and reduce the accumulation of ({sup 3}H)free fatty acids. It appeared that about half of the observed phospholipid catabolism was dependent on Ca{sup 2}{sup +} influx and that at least 80% of the ({sup 3}H)free fatty acid accumulation required calcium.

  14. The endogenous cannabinoid anandamide increases human airway epithelial cell permeability through an arachidonic acid metabolite.

    PubMed

    Shang, V C M; O'Sullivan, S E; Kendall, D A; Roberts, R E

    2016-03-01

    Injury to the bronchial epithelium in respiratory diseases such as asthma and COPD results in the loss of barrier function and an elevated sensitivity to environmental insults. An increased release of the endogenous cannabinoid, anandamide in response to inhalation of allergen in asthmatic patients has been reported. The aim of this study was, therefore, to determine the effects of endocannabinoids on bronchial epithelial cell permeability and to investigate the mechanisms involved. Calu-3 human bronchial epithelial cells were cultured at air-liquid interface to allow development of tight junctions. Changes in Transepithelial Electrical Resistance (TEER), a reflection of epithelial permeability, were measured at various time points post-treatment, and expression of the tight junction proteins, occludin and ZO-1, were determined using Western immunoblotting. Anandamide produced a significant reduction in TEER, which was unaffected by cannabinoid receptor antagonists, but attenuated by URB597, an inhibitor of fatty acid amide hydrolase, and by a combination of cyclooxygenase (COX) and lipoxygenase (LOX) blockade. The anandamide metabolite, arachidonic acid, showed similar TEER decrease that was also prevented in the presence of COX and LOX inhibitor. Expression of occludin and ZO-1 were also reduced by anandamide. These findings indicate a pro-inflammatory-like effect of anandamide on bronchial epithelial permeability, mediated by cyclooxygenase and lipoxygenase metabolites, and suggest that inhibition of anandamide degradation might provide a novel approach to treat airway inflammation. PMID:26808080

  15. Human mononuclear phagocytes from different anatomical sites differ in their capacity to metabolize arachidonic acid.

    PubMed Central

    Vicenzi, E; Biondi, A; Bordignon, C; Rambaldi, A; Donati, M B; Mantovani, A

    1984-01-01

    Human mononuclear phagocytes have the capacity to metabolize arachidonic acid (AA) into prostaglandins (PG) endowed with potent activities in immune responses and inflammatory processes. We have evaluated AA metabolism in human mononuclear phagocytes harvested from different anatomical sites (blood monocytes, macrophages from milk, peritoneal cavity and alveolar spaces). At thin layer radiochromatography, the AA metabolites mainly present were PGE2, TxB2 and, only in bronchoalveolar macrophages, a peak comigrating with PGD2. No appreciable levels of 6-keto-PGF1 alpha were observed. These data were confirmed using specific radioimmunoassays for TxB2, PGE2 and 6-keto-PGF1 alpha. Blood monocytes and bronchoalveolar macrophages were the poorest producers of PG, with the possible exception of PGD2 in bronchoalveolar macrophages. The high amounts of TxB2 and PGE2 produced by milk macrophages could contribute to the levels of PG in human milk. Thus, human mononuclear phagocytes obtained from diverse anatomical sites are considerably heterogeneous in terms of AA metabolism. PMID:6432383

  16. Temporal bone meningioma involving the middle ear: A case report

    PubMed Central

    RICCIARDIELLO, FILIPPO; FATTORE, LUCIA; LIGUORI, MARIA ESTER; OLIVA, FLAVIA; LUCE, AMALIA; ABATE, TERESA; CARAGLIA, MICHELE; PIANESE, ANNALISA; RAUCCI, ALDO FALCO

    2015-01-01

    Meningioma is a common intracranial tumor involving the meninges. The localization of this type of tumor is rarely extracranial due to its typically low invasive properties. Furthermore, invasion of the middle ear is exceptional. The present study reported a case of meningioma extending into the middle ear from the middle cranial fossa through the tegmen tympani. The clinical and pathological characteristics, as well as the outcome of the patient, were described. PMID:26622828

  17. SHIELD: an integrative gene expression database for inner ear research.

    PubMed

    Shen, Jun; Scheffer, Dborah I; Kwan, Kelvin Y; Corey, David P

    2015-01-01

    The inner ear is a highly specialized mechanosensitive organ responsible for hearing and balance. Its small size and difficulty in harvesting sufficient tissue has hindered the progress of molecular studies. The protein components of mechanotransduction, the molecular biology of inner ear development and the genetic causes of many hereditary hearing and balance disorders remain largely unknown. Inner-ear gene expression data will help illuminate each of these areas. For over a decade, our laboratories and others have generated extensive sets of gene expression data for different cell types in the inner ear using various sample preparation methods and high-throughput genome-wide approaches. To facilitate the study of genes in the inner ear by efficient presentation of the accumulated data and to foster collaboration among investigators, we have developed the Shared Harvard Inner Ear Laboratory Database (SHIELD), an integrated resource that seeks to compile, organize and analyse the genomic, transcriptomic and proteomic knowledge of the inner ear. Five datasets are currently available. These datasets are combined in a relational database that integrates experimental data and annotations relevant to the inner ear. The SHIELD has a searchable web interface with two data retrieval options: viewing the gene pages online or downloading individual datasets as data tables. Each retrieved gene page shows the gene expression data and detailed gene information with hyperlinks to other online databases with up-to-date annotations. Downloadable data tables, for more convenient offline data analysis, are derived from publications and are current as of the time of publication. The SHIELD has made published and some unpublished data freely available to the public with the hope and expectation of accelerating discovery in the molecular biology of balance, hearing and deafness. PMID:26209310

  18. SHIELD: an integrative gene expression database for inner ear research

    PubMed Central

    Shen, Jun; Scheffer, Dborah I.; Kwan, Kelvin Y.; Corey, David P.

    2015-01-01

    The inner ear is a highly specialized mechanosensitive organ responsible for hearing and balance. Its small size and difficulty in harvesting sufficient tissue has hindered the progress of molecular studies. The protein components of mechanotransduction, the molecular biology of inner ear development and the genetic causes of many hereditary hearing and balance disorders remain largely unknown. Inner-ear gene expression data will help illuminate each of these areas. For over a decade, our laboratories and others have generated extensive sets of gene expression data for different cell types in the inner ear using various sample preparation methods and high-throughput genome-wide approaches. To facilitate the study of genes in the inner ear by efficient presentation of the accumulated data and to foster collaboration among investigators, we have developed the Shared Harvard Inner Ear Laboratory Database (SHIELD), an integrated resource that seeks to compile, organize and analyse the genomic, transcriptomic and proteomic knowledge of the inner ear. Five datasets are currently available. These datasets are combined in a relational database that integrates experimental data and annotations relevant to the inner ear. The SHIELD has a searchable web interface with two data retrieval options: viewing the gene pages online or downloading individual datasets as data tables. Each retrieved gene page shows the gene expression data and detailed gene information with hyperlinks to other online databases with up-to-date annotations. Downloadable data tables, for more convenient offline data analysis, are derived from publications and are current as of the time of publication. The SHIELD has made published and some unpublished data freely available to the public with the hope and expectation of accelerating discovery in the molecular biology of balance, hearing and deafness. Database URL: https://shield.hms.harvard.edu PMID:26209310

  19. Serotonin stimulates phospholipase A2 and the release of arachidonic acid in hippocampal neurons by a type 2 serotonin receptor that is independent of inositolphospholipid hydrolysis.

    PubMed Central

    Felder, C C; Kanterman, R Y; Ma, A L; Axelrod, J

    1990-01-01

    Serotonin (5-HT) stimulated the release of arachidonic acid in hippocampal neurons cocultured with glial cells but not in glial cultures alone. Similar results were observed for the 5-HT-stimulated release of inositol phosphates. These results suggest a neural but not glial origin of both responses. Pharmacological studies suggested that release of arachidonic acid and inositol phosphates was mediated by a type 2 5-HT (5-HT2) receptor. 5-HT-stimulated release of arachidonic acid was also detected in cortical neurons, which contain high levels of 5-HT2 receptors, but not striatum, spinal cord, or cerebellar granule cells, which have very low levels or are devoid of 5-HT2 receptors. The phorbol ester phorbol 12-myristate 13-acetate augmented the 5-HT-stimulated release of arachidonic acid but inhibited the 5-HT-stimulated release of inositol phosphates. 5-HT-stimulated release of arachidonic acid, but not inositol phosphates, was dependent on extracellular calcium. 5-HT stimulated the release of [3H]lysophosphatidylcholine from [3H]choline-labeled cells with no increase in the release of [3H]choline or phospho[3H]choline. These data suggest that 5-HT stimulated the release of arachidonic acid in hippocampal neurons through the activation of phospholipase A2, independent of the activation of phospholipase C. PMID:2315313

  20. Serotonin stimulates phospholipase A sub 2 and the release of arachidonic acid in hippocampal neurons by a type 2 serotonin receptor that is independent of inositolphospholipid hydrolysis

    SciTech Connect

    Felder, C.C.; Ma, A.L.; Axelrod, J.; Kanterman, R.Y. )

    1990-03-01

    Serotonin (5-HT) stimulated the release of arachidonic acid in hippocampal neurons cocultured with glial cells but not in glial cultures alone. Similar results were observed for the 5-HT-stimulated release of inositol phosphates. These results suggest a neural but not glial origin of both responses. Pharmacological studies suggested that release of arachidonic acid and inositol phosphates was mediated by a type 2 5-HTT (5-HT{sub 2}) receptor. 5-HT-stimulated release of arachidonic acid was also detected in cortical neurons, which contain high levels of 5-HT{sub 2} receptors, but not striatum, spinal cord, or cerebellar granule cells, which have very low levels or are devoid of 5-HT{sub 2} receptors. The phorbol ester phorbol 12-myristate 13-acetate augmented the 5-HT-stimulated release of arachidonic acid but inhibited the 5-HT-stimulated release of inositol phosphates. 5-HT-stimulated release of arachidonic acid, but not inositol phosphates, was dependent on extracellular calcium. 5-HT stimulated the release of ({sup 3}H)lysophosphatidylcholine from ({sup 3}H)choline-labeled cells with no increase in the release of ({sup 3}H)choline or phospho({sup 3}H)choline. These data suggest that 5-HT stimulated the release of arachidonic acid in hippocampal neurons through the activation of phospholipase A{sub 2}, independent of the activation of phospholipase C.