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Sample records for arachidonic acid-induced ear

  1. Study on the suppressive effect of iodine-enriched egg on LT-C4 production in arachidonic acid-induced ear inflammation.

    PubMed

    Isono, E; Inoue, H; Aihara, M; Kubota, T; Ando, K; Ishida, H

    1993-01-01

    The anti-inflammatory mechanism of iodine-enriched egg was investigated in mice by means of arachidonic acid-induced ear inflammation. The lipid fraction of iodine-enriched egg was capable of suppressing the increase in ear weight induced by arachidonic acid in a dose-dependent manner. The lipid fraction was further separated into neutral and polar lipid fractions. Of these two fractions, only the neutral lipid fraction was capable of suppressing LT-C4 production in arachidonic acid inflammation. Neither the neutral nor polar lipid fractions of ordinary egg, however, showed any anti-inflammatory effect. These results suggest that the anti-inflammatory activity of iodine-enriched egg is present in the neutral lipid fraction, and its mechanism is assumed to be inhibition of LT-C4 production. PMID:8366766

  2. Intravenous anesthetic propofol suppresses prostaglandin E2 and cysteinyl leukotriene production and reduces edema formation in arachidonic acid-induced ear inflammation.

    PubMed

    Inada, Takefumi; Hirota, Kiichi; Shingu, Koh

    2015-01-01

    Propofol is an intravenous drug widely used for anesthesia and sedation. Previously, propofol was shown to inhibit cyclo-oxygenase (COX) and 5-lipoxygenase (5-LOX) activities. Because these enzyme-inhibiting effects have only been demonstrated in vitro, this study sought to ascertain whether similar effects might also be observed in vivo. In the current studies, effects of propofol were tested in a murine model of arachidonic acid-induced ear inflammation. Specifically, propofol - as a pre-treatment -- was intraperitoneally and then topical application of arachidonic acid was performed. After 1 h, tissue biopsies were collected and tested for the presence of edema and for levels of inflammatory mediators. The results indicated that the administration of propofol significantly suppressed ear edema formation, tissue myeloperoxidase activity, and tissue production of both prostaglandin E2 and cysteinyl leukotrienes. From the data, it can be concluded that propofol could exert anti-COX and anti-5-LOX activities in an in vivo model and that these activities in turn could have, at least in part, suppressed arachidonic acid-induced edema formation in the ear. PMID:25046027

  3. Activation of the central histaminergic system mediates arachidonic-acid-induced cardiovascular effects.

    PubMed

    Altinbas, Burcin; Topuz, Bora Burak; İlhan, Tuncay; Yilmaz, Mustafa Sertac; Erdost, Hatice; Yalcin, Murat

    2014-08-01

    The aim of this study was to explain the involvement of the central histaminergic system in arachidonic acid (AA)-induced cardiovascular effects in normotensive rats using hemodynamic, immunohistochemistry, and microdialysis studies. Intracerebroventricularly (i.c.v.) administered AA (0.25, 0.5, and 1.0 μmol) induced dose- and time-dependent increases in mean arterial pressure and decreased heart rate in conscious normotensive Sprague-Dawley rats. Central injection of AA (0.5 μmol) also increased posterior hypothalamic extracellular histamine levels and produced strong COX-1 but not COX-2 immunoreactivity in the posterior hypothalamus of rats. Moreover, the cardiovascular effects and COX-1 immunoreactivity in the posterior hypothalamus induced by AA (0.5 μmol; i.c.v.) were almost completely blocked by the H2 receptor antagonist ranitidine (50 and 100 nmol; i.c.v.) and partially blocked by the H1 receptor blocker chlorpheniramine (100 nmol; i.c.v.) and the H3-H4 receptor antagonist thioperamide (50 and 100 nmol; i.c.v.). In conclusion, these results indicate that centrally administered AA induces pressor and bradycardic responses in conscious rats. Moreover, we suggest that AA may activate histaminergic neurons and increase extracellular histamine levels, particularly in the posterior hypothalamus. Acting as a neurotransmitter, histamine is potentially involved in AA-induced cardiovascular effects under normotensive conditions. PMID:25065747

  4. 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

  5. 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; Östman, 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 naïve T cells. Spleen DCs from BALB/c mice were cultured in vitro with ovalbumin (OVA) with 50 μM fatty acids; α-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 IFNγ. 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

  6. 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

    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-κB) 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-α (TNF-α) and interleukin-6 (IL-6) and interleukin-1β (IL-1β). In addition, PW strongly suppressed inducible nitric oxide synthase (iNOS), a NO synthesis enzyme, induced heme oxygenase-1 (HO-1) expression and inhibited NF-κB activation and MAPK phosphorylation. Also, PW suppressed TNF-α, IL-6 and IL-1β 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

  7. 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-κB) 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-α (TNF-α) and interleukin-6 (IL-6) and interleukin-1β (IL-1β). In addition, PW strongly suppressed inducible nitric oxide synthase (iNOS), a NO synthesis enzyme, induced heme oxygenase-1 (HO-1) expression and inhibited NF-κB activation and MAPK phosphorylation. Also, PW suppressed TNF-α, IL-6 and IL-1β 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

  8. 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 ...

  9. Ear emergencies

    MedlinePlus

    Ear emergencies include objects in the ear canal and ruptured eardrums. ... Depending on the type of ear emergency, follow the steps below. OBJECT IN THE EAR Calm and reassure the person. If the object is sticking out and easy to ...

  10. Lipid-derived signals that discriminate wound- and pathogen-responsive isoprenoid pathways in plants: methyl jasmonate and the fungal elicitor arachidonic acid induce different 3-hydroxy-3-methylglutaryl-coenzyme A reductase genes and antimicrobial isoprenoids in Solanum tuberosum L.

    PubMed Central

    Choi, D; Bostock, R M; Avdiushko, S; Hildebrand, D F

    1994-01-01

    Induction of 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGR; EC 1.1.1.34) is essential for the synthesis of steroid derivatives and sesquiterpenoid phytoalexins in solanaceous plants following mechanical injury or pathogen infection. Gene-specific probes corresponding to different HMGR genes (hmg1 and hmg2) were used to study HMGR expression in potato tissue following treatment with methyl jasmonate, a lipoxygenase product of linolenic acid, or arachidonic acid, an elicitor present in the lipids of the potato late blight fungus Phytophthora infestans. Treatment of potato discs (2.2 cm in diameter) with low concentrations (0.45-45 nmol per disc surface) of methyl jasmonate nearly doubled the wound-induced accumulation of hmg1 transcripts and steroid-glycoalkaloid (SGA) accumulation, reduced the abundance of hmg2 transcripts, and did not induce phytoalexins. High concentrations of methyl jasmonate (2-4.5 mol per disc surface) suppressed hmg1 mRNA and SGA accumulation but did not affect hmg2 mRNA abundance or induce phytoalexins. In contrast, arachidonate treatment strongly suppressed hmg1 and strongly induced hmg2 mRNA in a concentration-dependent manner. There was a corresponding suppression of SGA accumulation and an induction of sesquiterpene phytoalexin accumulation by this elicitor. Lipoxygenase inhibitors reduced the wound-induced accumulation of hmg1 transcripts and suppressed SGA levels, effects that were overcome by exogenous methyl jasmonate (45 nmol per disc surface). The results (i) suggest that methyl jasmonate can function as a signal for hmg1 expression and SGA induction following wounding and (ii) indicate that the arachidonate- and jasmonate-response pathways are distinct in relation to HMGR gene expression and isoprenoid product accumulation. The results also are consistent with placement of the HMGR activities encoded by hmg1 and hmg2 within discrete steroid and sesquiterpenoid biosynthetic channels. Images PMID:11607466

  11. 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 ...

  12. Swimmer's ear

    MedlinePlus

    ... such as acetaminophen (Tylenol) or ibuprofen (Advil, Motrin) Vinegar (acetic acid) ear drops People with chronic swimmer's ear may ... drop of alcohol with 1 drop of white vinegar and placing the mixture into the ears after ...

  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 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, ...

  15. 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…

  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 wax

    MedlinePlus

    ... in the ear: Baby oil Commercial drops Glycerin Mineral oil Water Another method is to wash out the ... cloth or paper tissue wrapped around your finger. Mineral oil can be used to moisturize the ear and ...

  18. Ear Tubes

    MedlinePlus

    ... of recurrent ear infections and the need for repeat surgery in children four years and older. What happens ... soon (which is unpredictable), fluid may return and repeat surgery may be needed. Ear tubes that remain too ...

  19. Pierced Ears

    MedlinePlus

    ... clean your ears and put ear cleaning solution, rubbing alcohol, or antibiotic ointment on them. Whoever is doing ... Use a cotton ball or swab to apply rubbing alcohol or antibiotic ointment to the earlobe or lobes. ...

  20. 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? ...

  1. Super Ears.

    ERIC Educational Resources Information Center

    Thompson, Stan

    1995-01-01

    Presents an activity in which students design, construct, and test "super ears" to investigate sound and hearing. Students work in groups of three and explore how the outer ear funnels sound waves to the inner ear and how human hearing compares to that of other animals. (NB)

  2. Ear Infections

    MedlinePlus

    ... affects the middle ear and is called otitis media. The tubes inside the ears become clogged with fluid and mucus. This can affect hearing, because sound cannot get through all that fluid. If your child isn't old enough to say "My ear ...

  3. 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 ...

  4. The Property and Application of Arachidonic Acid

    NASA Astrophysics Data System (ADS)

    Wang, Xiang-qin; Yao, Jian-ming; Yuan, Cheng-ling; Wang, Ji; Yu, Zeng-liang

    2002-10-01

    Arachidonic acid (AA) is one of the most important PUFAs (polyunsaturated fatty acids) in human body. A high-yield arachidonic acid-producing strain (mortierella alpina) was selected by ion implantation (the relative content of arachidonic acid is 70.2% among all fatty acids). This paper mainly introduced the structure, distribution, source, physiologic healthcare function and application of AA.

  5. Ear Infections

    MedlinePlus

    ... through the ear canal and hit the eardrum and cause it to vibrate. The vibration of the eardrum causes the tiny bones in ... psoriasis) that occur in other parts of the body can also occur in the ear canal and cause an infection. Bacteria from products you use ...

  6. Elephant ear

    MedlinePlus

    Elephant ear plants are indoor or outdoor plants with very large, arrow-shaped leaves. Poisoning may occur ... The harmful substances in elephant ear plants are: Oxalic acid Asparagine, a protein found in this plant Note: Leaves and stems are the most dangerous ...

  7. 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.

  8. Cosmetic ear surgery

    MedlinePlus

    Otoplasty; Ear pinning; Ear surgery - cosmetic; Ear reshaping; Pinnaplasty ... Cosmetic ear surgery may be done in the surgeon's office, an outpatient clinic, or a hospital. It can be performed under ...

  9. Ear defects.

    PubMed

    Shonka, David C; Park, Stephen S

    2009-08-01

    The projection and exposure of the auricle make it particularly susceptible to actinic injury and thus to cutaneous malignancies. Auricular reconstruction is challenging because of its unique surface anatomy and undulating topography. This article organizes auricular defects into different categories based on anatomic location and extent of tissue loss, including skin-only defects, small composite defects, full-thickness defects involving or sparing the upper third of the ear, and total auricular loss. The authors share an algorithm for repair of the array of auricular defects. PMID:19698921

  10. Ear Plastic Surgery

    MedlinePlus

    ... Find an ENT Doctor Near You Ear Plastic Surgery Ear Plastic Surgery Patient Health Information News media ... weight earrings. Does Insurance Pay for Cosmetic Ear Surgery? Insurance usually does not cover surgery solely for ...

  11. Ear tube insertion

    MedlinePlus

    Myringotomy; Tympanostomy; Ear tube surgery; Pressure equalization tubes; Ventilating tubes; Ear infection - tubes; Otitis - tubes ... trapped fluid can flow out of the middle ear. This prevents hearing loss and reduces the risk ...

  12. 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 awoke with a sharp pain in his ear — it really hurt! He remembered having ear infections ...

  13. Swimmer's Ear (For Parents)

    MedlinePlus

    ... for Your Child All About Food Allergies Swimmer's Ear (Otitis Externa) KidsHealth > For Parents > Swimmer's Ear (Otitis ... español Otitis del nadador (otitis externa) About Swimmer's Ear Otitis externa (OE) — commonly known as swimmer's ear — ...

  14. 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

  15. 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 ...

  16. Ear Infection and Vaccines

    MedlinePlus

    ... an ENT Doctor Near You Ear Infection and Vaccines Ear Infection and Vaccines Patient Health Information News ... or may need reinsertion over time. What about vaccines? A vaccine is a preparation administered to stimulate ...

  17. Ear infection - chronic

    MedlinePlus

    Middle ear infection - chronic; Otitis media - chronic; Chronic otitis media; Chronic ear infection ... Chole RA. Chronic otitis media, mastoiditis, and petrositis. In: Flint PW, Haughey BH, Lund LJ, et al, eds. Cummings Otolaryngology: Head & Neck Surgery . 6th ed. ...

  18. 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 ...

  19. 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 ...

  20. 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- ...

  1. 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

  2. [The solitary ear].

    PubMed

    Garzón Calles, J A

    1996-01-01

    An unique ear refers to those cases of individuals with an air and/or bone conduction allowing a serviceable hearing in one ear, being the other one totally lost, owing to any disease. So it is relatively frequent patients presenting only one ear normal, being the other one deaf. The puzzle rises when the sole running good ear must be operated, for whichever pathology. It may be that these various circumstances were: double cholesteatoma, cholesteatoma with extreme loss of hearing, otosclerosis with total deafness and even patients with chronic middle ear otitis and progressive impairment of bilateral hearing. Before to take the final decision on behalf of surgery we must consider: the ear condition, the age and physical state, the job and the social activity and finally the desire and resolution of the patient himself as well. The paper explain our experience in dealing with 10 solitary ears seen in the last 6 years. PMID:8967558

  3. Arachidonic acid facilitates experimental chronic osteomyelitis in rats.

    PubMed Central

    Rissing, J P; Buxton, T B; Fisher, J; Harris, R; Shockley, R K

    1985-01-01

    Arachidonic acid was used as a facilitating agent in experimental rat Staphylococcus aureus osteomyelitis and compared with the more commonly used agent, sodium morrhuate. The injection of arachidonic acid or sodium morrhuate and S. aureus into rat tibiae caused increased quantitative bacterial bone counts, gross bone pathology, roentgenographic changes, and weight loss. The doses required to produce these changes appeared to be lower for arachidonic acid. PMID:3924826

  4. Control of arachidonic acid release in chick muscle cultures

    NASA Technical Reports Server (NTRS)

    Templeton, G. H.; Padalino, M.; Wright, W.

    1985-01-01

    Cultures from thigh muscles of 12 day old embryonic chicks are utilized to examine arachidonic release, prostaglandin (PG) biosynthesis, and protein synthesis. The preparation of the cultures is described. It is observed that exogenous arachidonic acid is formed into photsphatidylethanolamine and phosphatidylcholine, is released by a calcium ionosphere or phospholiphase simulator, and is the substrate for the biosynthesis of PG; the epidermal growth factor and PGF do not stimulate protein synthesis over the basal levels. The relationship between arachidonate release and melittin is studied. The data reveal that a change in intracellular calcium stimulates phospholiphase activity, arachidonate release, and PG synthesis in chick muscle culture.

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

    MedlinePlus

    ... Food Allergies Middle Ear Infections and Ear Tube Surgery KidsHealth > For Parents > Middle Ear Infections and Ear ... medio y colocación de tubos de ventilación Why Surgery? Many kids get middle ear infections (known as ...

  6. 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

  7. DIFFERENCES IN ARACHIDONIC ACID METABOLISM BY HUMAN MYELOMONCYTIC CELL LINES

    EPA Science Inventory

    The production of arachidonic acid metabolites by the HL60, ML3, and U937 human phagocyte cell lines were determined after incubation with interferongamma (IFNg; 500 U/ml) or vehicle for 4 days. ells were prelabeled with tritiated arachidonic acid for 4 hours, and media supernata...

  8. 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 ...

  9. 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 ...

  10. 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 ...

  11. Arachidonic acid and ion channels: an update

    PubMed Central

    Meves, H

    2008-01-01

    Arachidonic acid (AA), a polyunsaturated fatty acid with four double bonds, has multiple actions on living cells. Many of these effects are mediated by an action of AA or its metabolites on ion channels. During the last 10 years, new types of ion channels, transient receptor potential (TRP) channels, store-operated calcium entry (SOCE) channels and non-SOCE channels have been studied. This review summarizes our current knowledge about the effects of AA on TRP and non-SOCE channels as well as classical ion channels. It aims to distinguish between effects of AA itself and effects of AA metabolites. Lipid mediators are of clinical interest because some of them (for example, leukotrienes) play a role in various diseases, others (such as prostaglandins) are targets for pharmacological therapeutic intervention. PMID:18552881

  12. Ear lobe reconstruction with a posterior ear flap. Case reports.

    PubMed

    Savaci, N; Tosun, Z; Hoşnuter, M

    2000-06-01

    We describe a technique for reconstruction of the ear lobe. Although there are many procedures that aim to reconstruct the ear lobe naturally, the aesthetic results of using a posterior ear flap are better because the scar tissue that remains behind the ear is invisible. PMID:10900635

  13. External Otitis (Swimmer's Ear)

    MedlinePlus

    ... Injuring the ear canal while cleaning it (using cotton-tipped swabs) or getting water or irritants, such ... these devices are not properly cleaned. Use of cotton-tipped swabs is a very common risk factor ...

  14. 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 ...

  15. External Otitis (Swimmer's Ear)

    MedlinePlus

    ... after swimming (as long as there is no hole [perforation] in the eardrum). Attempting to clean the ... is the most common cause of perforation (a hole) of the eardrum? Objects entering the ear Middle ...

  16. 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 ...

  17. Infrared ear thermometry.

    PubMed

    1991-11-01

    Many hospitals are considering using infrared (IR) ear thermometers (also called tympanic membrane thermometers) as an alternative to traditional temperature-measurement devices. IR technology allows users to quickly and noninvasively measure body temperature by inserting a directional probe into the ear canal. For infection control, ear thermometers offer the advantages of not contacting mucous membranes and eliminating the need for special handling procedures. For use on unconscious patients or those who are otherwise unwilling or unable to cooperate with traditional techniques, IR ear thermometers offer a more comfortable and less stressful method of temperature taking for both patients and nurses, especially where rectal temperatures are used. The recent entry into this market by major companies and distributors and the release of several new IR ear thermometers have helped to further stimulate interest in this technology. However, a complete transition to IR ear thermometers throughout the hospital may not be necessary and should be made only after these devices have been successfully used in selected clinical locations, such as emergency departments, critical care areas, recovery areas, and labor and delivery rooms. Clinical users must be familiar with the technique needed for temperature measurement with these instruments and understand the differences between temperatures taken in the ear canal and those obtained from traditional sites. In the following article, we first present and overview of clinical thermometry, describing traditional temperature-measurement sites and devices. We then discuss the advantages and disadvantages of using the ear canal, including the tympanic membrane (TM), as a site for temperature measurement.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1743976

  18. 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...

  19. 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.

  20. 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

  1. 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

  2. What Is an Ear Infection?

    MedlinePlus

    ... Words En Español What Other Kids Are Reading Movie: Digestive System Winter Sports: Sledding, Skiing, Snowboarding, Skating ... For Kids For Parents MORE ON THIS TOPIC Movie: Ears Your Ears What's Hearing Loss? Taking Care ...

  3. Reconstructive Middle Ear Surgery

    PubMed Central

    Ruby, R.R.F.; Ballagh, R.H.

    1992-01-01

    Conductive hearing loss is a common cause of deafness and disability, particularly in children and young adults. This article presents a brief overview of the various methods currently available for reconstructing the tympanic membrane and middle ear ossicular chain, including some comments as to their indications and limitations. Schematic diagrams showing these techniques illustrate the various types of repair described. PMID:21221356

  4. 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 ...

  5. 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…

  6. 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.

  7. Ear Infections and Language Development.

    ERIC Educational Resources Information Center

    Roberts, Joanne E.; Zeisel, Susan A.

    Ear infections in infants and preschoolers can cause mild or moderate temporary hearing loss, which may in turn affect a child's ability to understand and learn language. Noting that providing children with proper medical treatment for ear infections or middle ear fluid is important in preventing possible problems with language development, this…

  8. Neurologic evaluation of the ear.

    PubMed

    Cook, Laurie B

    2004-03-01

    Diseases of the ear often cause signs of neurologic dysfunction because of damage of peripheral nervous system structures associated with the middle and inner ear. Vestibular dysfunction, facial paralysis, Horner's syndrome, and hearing deficits are the most common neurologic deficits that accompany middle and inner ear disease. Differentiating these signs from disease of the central nervous system is crucial for an accurate diagnosis and prognosis but can be difficult. Understanding the normal anatomy of the ear and its association with the brain is crucial to interpretation of the neurologic examination. This article reviews neurologic dysfunction commonly associated with diseases of the ear and differentiating these signs from central disease. PMID:15062617

  9. 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...

  10. 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.

  11. 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 20 years 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

  12. [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

  13. 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 ...

  14. 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 ...

  15. Successful Bilateral Composite Ear Reattachment

    PubMed Central

    2014-01-01

    Summary: A successful bilateral ear composite graft nonmicrosurgical reattachment is presented. In cases where suitable vessels are unavailable for microsurgical revascularization, the reconstructive challenge can be formidable for salvaging the unique anatomic and aesthetic structure of the ear. The case is presented of an 18-year-old woman who was a victim of an assault wherein both of her ears were intentionally amputated by her attacker. She underwent successful surgical reattachment followed by a postoperative regimen of hyperbaric oxygen, cooling, and meticulous wound care. The patient achieved 100% survival of her left ear graft and 95% survival of her right ear graft. Clinical photographs at 18 months are presented, along with a discussion of the possible implications for other reconstructive applications. PMID:25289367

  16. 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

  17. Otoplasty for the Protruded Ear

    PubMed Central

    Nazarian, Ronen; Eshraghi, Adrien A.

    2011-01-01

    The prominent ear can produce significant social and psychological effects on an individual. Through the last century, many procedures have been described to correct this deformity. In this review, the authors navigate through the history of otoplasty for the protruded ear, and describe some of the breakthroughs in the procedure. Furthermore, they discuss key measurements that must be kept in mind in preoperative and intraoperative settings. They also describe in more detail some of the more common methods for correcting the protruded ear, as well as postoperative management and common complications faced after surgery. PMID:23115535

  18. [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

  19. Ototoxicity (Ear Poisoning) (For Parents)

    MedlinePlus

    ... Kids Up for Sports Pregnant? Your Baby's Growth Cerebral Palsy: Caring for Your Child All About Food Allergies ... Speech or Language Development Speech-Language Therapy Physical ... Loss? Can Loud Music Hurt My Ears? Going to the Audiologist Hearing ...

  20. Diseases of the ear pinna.

    PubMed

    Matousek, Jennifer L

    2004-03-01

    In conclusion, there are a wide variety of dermatologic diseases that can affect the ear pinnae. Most of these disorders are manifestations of a generalized dermatosis. Therefore, when pinnal lesions are present, a thorough diagnostic workup is indicated. PMID:15062622

  1. Autoimmune Inner Ear Disease (AIED)

    MedlinePlus

    ... Canal Dehiscence (SCD) Tinnitus Vestibular Hyperacusis Vision & Hearing Psychology Diet Other Topics Military Resources Infographics & Presentations Paid ... in women than men and less frequently in children and the elderly. When the ear is attacked, ...

  2. Taking Care of Your Ears

    MedlinePlus

    ... your hands before touching your pierced ears. Applying rubbing alcohol also can help keep germs away. With an adult's help, soak a cotton ball in rubbing alcohol and apply it to both sides of the ...

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

    MedlinePlus

    ... Work: Healthy Swimming Policy & Recommendations Fast Facts Healthy Water Sites Healthy Water Drinking Water Healthy Swimming Global ... you requested has moved to Ear Infections. Healthy Water Sites Healthy Water Drinking Water Healthy Swimming Global ...

  4. 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...

  5. 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...

  6. 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...

  7. 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

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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.

  13. Oxidation of esterified arachidonate by rat liver microsomes

    SciTech Connect

    Davis, H.W.; Suzuki, T.; Schenkman, J.B.

    1986-03-05

    The authors have previously demonstrated a relationship between phospholipid arachidonate in liver microsomes and malondialdehyde (MDA) formation during lipid peroxidation. In this study arachidonic acid (U-/sup 14/C) was incorporated into rat liver microsomes and NADPH-supported peroxidation was carried out at 37/sup 0/C for 15 minutes. The microsomes were pelleted by centrifugation and the labeled products in the supernatant were isolated by a solid phase method. Pellets were hydrolyzed with phospholipase A/sub 2/ and extracted with diethyl ether and the products from both fractions were separated by reverse phase HPLC. The results show that (1) oxidation occurs in all of the major phospholipids but that phosphatidylethanolamine is the most susceptible; (2) a linear correlation exists between MDA formation and supernatant radioactivity; (3) several different polar products are found in both the supernatant and the hydrolyzed pellet but that the ratios of product peaks in HPLC do not change during the peroxidation, indicating no secondary metabolism or propagation; and (4) cytochrome P-450 is not involved in the peroxidative reactions since no oxidation occurs in the absence of Fe/sup 3 +/ and since product formation is unaffected in the presence of carbon monoxide.

  14. 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

  15. 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

  16. 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

  17. Measurement of the incorporation of orally administered arachidonic acid into tissue lipids

    SciTech Connect

    Kulmacz, R.J.; Sivarajan, M.; Lands, W.E.

    1986-01-01

    The applicability of a stable isotope method to monitor the mixing of dietary arachidonic acid with endogenous arachidonic acid in tissue lipids was evaluated. Rats were fed octadeuterated arachidonic acid during a 20-day period, and the entry of the dietary acid into lipid esters of various tissues was examined by gas chromatography-mass spectrometric (GC-MS) analysis of their fatty acids. The rats were maintained on a fat-free diet from weaning until 63 days old to enhance the ratio of the dietary acid to endogenous arachidonate. Three separate forms of eicosatetraenoic acid in the tissue lipids could be distinguished by GC-MS: octadeuterated arachidonic acid (recent dietary origin), unlabeled arachidonic acid (maternal origin) and unlabeled 4,7,10,13-eicosatetraenoic acid (originating from palmitoleic acid). The total eicosatetraenoic acid in the tissue lipids contained about 90% arachidonate from recent dietary origin in lung, kidney, heart and fat, 70% in muscle and liver and 27% in brain. The n-7 isomer of eicosatetraenoic acid was estimated to make up 6% or less of the total eicosatetraenoic acid in lung, kidney, brain, muscle and heart tissue lipids, but it comprised around 15% of the total eicosatetraenoic acid in liver. The unlabeled arachidonic acid of maternal origin thus comprised only about 10% of the eicosatetraenoic acid in all tissues examined except muscle and brain, where it was 24% and 70% of the eicosatetraenoic acid, respectively.

  18. [Changes, induced by certain flavonoids, of the hypotensive effects of arachidonic acid].

    PubMed

    Damas, J; Mousty, J C; Lecomte, J

    1977-01-01

    In the rat, silybine and Z 12007, a derivative of rutoside, increase the vasodepressive activities of arachidonic acid, a prostaglandin precursor. They reduce the activity of PGE2. Quercetine also increases the hypotensive action of arachidonic acid. These three flavonoids are supposed to increase the prostaglandin biosynthesis. PMID:143326

  19. 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

  20. 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

  1. Antagonism by antipyretics of the hyperthermic effect of a prostaglandin precursor, sodium arachidonate, in the cat.

    PubMed Central

    Clark, W G; Cumby, H R

    1976-01-01

    1. Injection of sodium arachidonate (100-400 mug) into lateral cerebral ventricles of unanaesthetized cats caused shivering and rapid development of dose-related hyperthermic responses. Unless arachidonate is hyperthermogenic per se, this indicates that in vivo formation of prostaglandins, or perhaps an endoperoxide intermediate, can cause hyperthermia. 2. Tolerance gradually developed when arachidonate was administered repeatedly at intervals of 1-7 days. Examination of the brains of several tolerant animals revealed in each case marked enlargement of the lateral ventricles which apparently accounted for the diminished response to arachidonate. 3. Sodium salicylate (40, 160 mg/kg, i.v.) antagonized arachidonate but only after a 3-4 hr latent period. 4. Paracetamol (10, 40 mg/kg, i.v.) reduced the hyperthermic effect of arachidonate but a dose of 40 mg/kg antagonized centrally administered bacterial endotoxin more effectively than it did arachidonate. 5. Indomethacin (40 mug/kg, i.v.) significantly reduced arachidonate-induced hyperthermia in only one of two studies. This reduction was comparable to the hypothermic effect of indomethacin in afebrile animals and was attributed to a non-specific action on thermoregulatory function rather than to inhibition of prostaglandin synthesis. Indomethacin antagonized endotoxin and leucocytic pyrogen to a greater degree than it did arachidonate. 6. Comparison of the relative effectiveness of the antipyretics in blocking hyperthermic responses to pyrogens and to sodium arachidonate indicates that, if prostaglandins do mediate pyrogen-induced fever, these antipyretics exert their primary at a step before prostaglandin synthesis. PMID:950606

  2. 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

  3. 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

  4. 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.

  5. 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

  6. 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.

  7. 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

  8. Middle Ear Infections (For Parents)

    MedlinePlus

    ... speak. Sound, which is made up of invisible waves of energy, causes these vibrations. Every time you hear a sound, the various structures of the ear have to work together to make sure ... Hearing begins when sound waves that travel through the air reach the outer ...

  9. 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

  10. 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

  11. 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 ...

  12. Handedness and Preferred Ear for Telephoning.

    ERIC Educational Resources Information Center

    Williams, Stephen M.

    1987-01-01

    Examined relationship between handedness and preferred ear for telephoning in 140 college students. Increased degree of sinistrality was associated with increased tendency to use left ear for telephoning. Found tendency to pick up telephone receiver with preferred hand and hold earpiece to ipsilateral ear. Results may relate to reports of reduced…

  13. 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)

  14. 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...

  15. 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...

  16. 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...

  17. 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 μL (0.228 μL for males and 0.218 μL 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

  18. The influence of mono- and divalent cations on the cardiac metabolism of arachidonic acid

    SciTech Connect

    Weis, M.T.; Malik, K.U. )

    1989-06-01

    Our previous study indicated that, in the isolated rabbit heart, perfusion with Ca2+ free Krebs Henseleit buffer (KHB) results in increased conversion of exogenous arachidonic acid to PGE2 and 6-keto-PGF1 alpha, probably as the result of increased availability of substrate to cyclooxygenase. Since perfusion with Ca2+ free buffer is known to cause alterations in the cardiac content of various mono- and divalent cations, the present study was performed to determine: (a) The relationship between the conversion of exogenous arachidonic acid to prostaglandins and cardiac content of Na+, K+, Ca2+ and Mg2+; and (b) Whether enhanced arachidonic acid conversion to prostaglandins during Ca2+ free perfusion is due to reduced incorporation of this fatty acid into tissue lipids. Perfusion of the rabbit heart with Ca2+ free buffer produced a significant reduction in the tissue content of Na+, K+, Ca2+ and Mg2+. However, the production of 6-keto-PGF1 alpha from exogenous arachidonic acid was linearly correlated with tissue Mg2+. These observations, together with our finding that perfusion with Ca2+ free KHB reduced the incorporation of (3H) arachidonic acid into tissue lipids, suggests that Ca2+ free perfusion may, by reducing the activity of arachidonyl CoA synthetase (a Mg2+ dependent enzyme), decrease the acylation of arachidonic acid into lipids, thus increasing the availability of arachidonic acid to cyclooxygenase.

  19. 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

  20. Autogenous and prosthetic reconstruction of the ear.

    PubMed

    Louis, Patrick J; Aponte-Wesson, Ruth A; Fernandes, Rui P; Clemow, Justin

    2013-05-01

    Injuries to the ear can result in partial or complete loss of the external ear. Resection of the external ear may be necessary secondary to malignant tumor or infection. This article discusses the diagnosis and management of acquired defects of the external ear. Because autogenous reconstruction is not always possible, both autogenous and prosthetic reconstruction are presented as well as the indications for both. This information should help guide the clinician in the decision-making process. In the hands of experienced clinicians, reconstruction of the external ear can result in an excellent outcome, with improved quality of life for the patient. PMID:23522966

  1. [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

  2. 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

  3. 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

  4. 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.

  5. Unsaturated fatty acids induce non-canonical autophagy

    PubMed Central

    Niso-Santano, Mireia; Malik, Shoaib Ahmad; Pietrocola, Federico; Bravo-San Pedro, José Manuel; Mariño, Guillermo; Cianfanelli, Valentina; Ben-Younès, 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, Gérard; Tavernarakis, Nektarios; Cecconi, Francesco; Maiuri, Maria Chiara; Galluzzi, Lorenzo; Kroemer, Guido

    2015-01-01

    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

  6. Virus-induced enhancement of arachidonate metabolism by bovine alveolar macrophages in vitro

    SciTech Connect

    Laegreid, W.W.; Taylor, S.M.; Leid, R.W.; Silflow, R.M.; Evermann, J.R.; Breeze, R.G.; Liggitt, H.D.

    1989-04-01

    Virus infection of alveolar macrophages both in vivo and in vitro has been associated with a variety of changes in cellular function. Some of these changes are identical to the effects that arachidonate-derived mediators, prostaglandins, leukotrienes, and hydroxyeicosatetraenoic acids, have on macrophage function. Virus infection of macrophages has been previously shown to increase the output of some arachidonate metabolites, most notably PGE2. However, the effect of virus infection on arachidonate metabolism in general has not been well described. In our experiments, primary cultures of alveolar macrophages obtained from normal cattle by bronchoalveolar lavage, were infected in vitro with parainfluenza type 3 virus. At days 0 to 4 post-infection (p.i.) these cells were labelled with 3H-arachidonic acid and stimulated with either serum-coated zymosan, the calcium ionophore A23187, or phorbol myristate acetate. The complete spectrum of arachidonate-derived metabolites was determined by reverse-phase high performance liquid chromatography with UV and on-line radiometric monitoring of column eluant. The total output of metabolites of arachidonic acid by virus-infected alveolar macrophages was increased over that of noninfected controls (with all stimuli tested) by day 4 p.i. (P less than or equal to 0.05). The production of metabolites by the cyclooxygenase, 12- and 5-lipoxygenase enzyme systems was significantly increased, as was the release of 3H-arachidonate. The lack of stimulus specificity and the increases in arachidonate release suggest that greater substrate availability, due either to increased phospholipase activity or direct virus-membrane interaction, may be responsible for the virus-induced enhancement of metabolite output.

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

    NASA Astrophysics Data System (ADS)

    Delnavaz, Aidin; Voix, Jérémie

    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.

  8. 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

  9. 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.

  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. 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.

  12. Direct inhibition of gastric secretion and mucosal blood flow by arachidonic acid.

    PubMed Central

    Konturek, S J; Mikoś, E; Pawlik, W; Waluś, K

    1979-01-01

    1. Gastric acid and pepsin secretion stimulated almost maximally by i.v. infusion of histamine, the mucosal blood flow, and the immunoreactive prostaglandin E (PGE) content have been measured following arachidonic acid administration either intra-arterially or topically to the mucosa of the fundic portion of a stomach kept in a Lucite chamber. 2. Arachidonic acid administered directly to the stomach produced a marked and significant inhibition of histamine-induced gastric secretion accompanied by a reduction in mucosal microcirculation and a rise in the immunoreactive PGE content in the gastric juice. 3. These secretory and circulatory changes induced by arachidonic acid were prevented by pretreatment of the gastic mucosa with indomethacin, a potent inhibitor of the prostaglandin synthetase system. 4. Arachidonic acid infused intra-arterially in graded doses resulted in a dose-dependent reduction in gastric acid secretion, mucosal blood flow and cyclic AMP mucosal content. 5. These studies indicate that arachidonic acid applied directly to the stomach causes a marked gastric secretory inhibition, probably due at least in part to the enzymic transformation of arachidonic acid to prostaglandins and possibly other active lipids responsible for the changes in the gastric mucosal microcirculation and cyclic AMP mucosal content. PMID:220411

  13. Cytochrome P450 arachidonic acid metabolism in bovine corneal epithelium

    SciTech Connect

    Masferrer, J.; Schwartzman, M.L.; Abraham, N.G.; Dunn, M.W.; McGiff, J.C.

    1986-03-01

    The presence of the cytochrom P450 system and its involvement in the metabolism of AA was studied in the corneal epithelium. This tissue contains cytochrome P450 as assessed directly by measurement of the carbon monoxide reduced spectrum (specific activity of 161 pmol/10 mg protein) and indirectly by measuring the activity of aryl hydrocarbon hydroxylase (AHH) - a cytochrome P450-dependent enzyme (11-39 pmol 3-OH benzopyrene/mg protein/10 min). When corneal epithelial microsomes were incubated with /sup 14/C-arachidonic acid, 30-50% of the total radioactivity was converted to two peaks, I and II. Further separation using high performance liquid chromatography has shown that each peak contains two metabolites, A,B and C,D. Metabolite formation was dependent on the addition of NADPH (1 mM) and inhibited by carbon monoxide and SKF-525A (100 ..mu..M) suggesting a cytochrome P450-dependent mechanism. Compound C (5-10 ..mu..M) inhibited the activity of corneal epithelial Na-K-ATPase by 30-60%, being 100-fold more potent than ouabain. Compound D (10-100 ng) induced a dose dependent relaxation of the rat caudal artery. Compound D also inhibited corneal Na-K-ATPase activity but less potently than compound C. These compounds may be important to transport processes of ocular epithelia and participate in the control of the ocular circulation and aqueous humor dynamics.

  14. 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

  15. The Essentiality of Arachidonic Acid in Infant Development.

    PubMed

    Hadley, Kevin B; Ryan, Alan S; Forsyth, Stewart; Gautier, Sheila; Salem, Norman

    2016-01-01

    Arachidonic acid (ARA, 20:4n-6) is an n-6 polyunsaturated 20-carbon fatty acid formed by the biosynthesis from linoleic acid (LA, 18:2n-6). This review considers the essential role that ARA plays in infant development. ARA is always present in human milk at a relatively fixed level and is accumulated in tissues throughout the body where it serves several important functions. Without the provision of preformed ARA in human milk or infant formula the growing infant cannot maintain ARA levels from synthetic pathways alone that are sufficient to meet metabolic demand. During late infancy and early childhood the amount of dietary ARA provided by solid foods is low. ARA serves as a precursor to leukotrienes, prostaglandins, and thromboxanes, collectively known as eicosanoids which are important for immunity and immune response. There is strong evidence based on animal and human studies that ARA is critical for infant growth, brain development, and health. These studies also demonstrate the importance of balancing the amounts of ARA and DHA as too much DHA may suppress the benefits provided by ARA. Both ARA and DHA have been added to infant formulas and follow-on formulas for more than two decades. The amounts and ratios of ARA and DHA needed in infant formula are discussed based on an in depth review of the available scientific evidence. PMID:27077882

  16. The Essentiality of Arachidonic Acid in Infant Development

    PubMed Central

    Hadley, Kevin B.; Ryan, Alan S.; Forsyth, Stewart; Gautier, Sheila; Salem, Norman

    2016-01-01

    Arachidonic acid (ARA, 20:4n-6) is an n-6 polyunsaturated 20-carbon fatty acid formed by the biosynthesis from linoleic acid (LA, 18:2n-6). This review considers the essential role that ARA plays in infant development. ARA is always present in human milk at a relatively fixed level and is accumulated in tissues throughout the body where it serves several important functions. Without the provision of preformed ARA in human milk or infant formula the growing infant cannot maintain ARA levels from synthetic pathways alone that are sufficient to meet metabolic demand. During late infancy and early childhood the amount of dietary ARA provided by solid foods is low. ARA serves as a precursor to leukotrienes, prostaglandins, and thromboxanes, collectively known as eicosanoids which are important for immunity and immune response. There is strong evidence based on animal and human studies that ARA is critical for infant growth, brain development, and health. These studies also demonstrate the importance of balancing the amounts of ARA and DHA as too much DHA may suppress the benefits provided by ARA. Both ARA and DHA have been added to infant formulas and follow-on formulas for more than two decades. The amounts and ratios of ARA and DHA needed in infant formula are discussed based on an in depth review of the available scientific evidence. PMID:27077882

  17. 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.

  18. 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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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.

  5. 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

  6. Milestones in the History of Ear Reconstruction.

    PubMed

    Berghaus, Alexander; Nicoló, 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

  7. Lipoxygenation of arachidonic acid by subcellular preparations from murine keratinocytes

    SciTech Connect

    Ziboh, V.A.; Casebolt, T.L.; Marcelo, C.L.; Voorhees, J.J.

    1984-10-01

    In these studies, we examined the possibility that cell-free preparations from murine keratinocytes possess 5-lipoxygenase activity in addition to the well-established cyclooxygenase pathway of arachidonic acid (AA) in these cells. Our data demonstrated that the high-speed (105,000 g) supernatant preparations of the murine keratinocytes metabolized (14C)AA into labeled lipoxygenase products. Portions of these radioactive metabolites cochromatographed and comigrated with 12-HETE (a marker for 12-lipoxygenase pathway) and with authentic LTB4 (a marker for 5-lipoxygenase pathway) on silicic acid column chromatography and by thin-layer chromatography (TLC) in two solvent systems respectively. Identity of the novel 14C which comigrated with LTB4 on both TLC and column chromatography was verified further by cochromatography of the free acid with authentic LTB4 on a reverse phase (RP) and the methyl esters on a straight phase high-pressure liquid chromatography. Incubation of the cell-free preparations with (14C)AA in the presence of ETYA, NDGA (inhibitors of cyclooxygenase and lipoxygenase pathways) as well as with 15-HETE (an inhibitor of lipoxygenase pathway) resulted in decreased formation of (14C) 12-HETE and the (14C)LTB4-like metabolite. On the contrary, incubations of the cell-free extracts with (14C) AA in the presence of indomethacin (a cyclooxygenase inhibitor) resulted in increased biosynthesis of the labeled lipoxygenase metabolites. These data indicate the existence of enzymes in soluble fraction of murine keratinocyte which can catalyze the transformation of (14C) AA into products of both the 12- and 5-lipoxygenase pathways.

  8. Arachidonic acid metabolism in silica-stimulated bovine alveolar macrophages

    SciTech Connect

    Englen, M.D.

    1989-01-01

    The in vitro production of arachidonic acid (AA) metabolites in adherent bovine alveolar macrophages (BAM) incubated with silica was investigated. BAM were pre-labelled with {sup 3}H-AA, and lipid metabolites released into the culture medium were analyzed by high performance liquid chromatography (HPLC). Lactate dehydrogenase (LDH) release was simultaneously assayed to provide an indication of cell injury. Increasing doses of silica selectively stimulated the 5-lipoxygenase pathway of AA metabolism, while cyclooxygenase metabolite output was suppressed. LDH release increased in a linear, dose-dependent fashion over the range of silica doses used. Moreover, within 15 min following addition of a high silica dose, a shift to the production of 5-lipoxygenase metabolites occurred, accompanied by a reduction in cyclooxygenase products. This rapid alteration in AA metabolism preceded cell injury. To examine the relationship between cytotoxicity and AA metabolite release by BAM exposed to silicas with different cytotoxic and fibrogenic activities, BAM were exposed to different doses of DQ-12, Minusil-5, and Sigma silicas, and carbonyl iron beads. The median effective dose (ED{sub 50}) of each particulate to stimulate the release of AA metabolites and LDH was calculated. The ED{sub 50} values for DQ-12, Minusil-5, and Sigma silica showed that the relative cytotoxicities of the different silicas for BAM corresponded to the relative potencies of the silicas to elicit 5-lipoxygenase metabolites from BAM. These results indicate that the cytotoxic, and presumed fibrogenic potential, of a silica is correlated with the potency to stimulate the release of leukotrienes from AM.

  9. Docosahexaenoic acid affects arachidonic acid uptake in megakaryocytes

    SciTech Connect

    Schick, P.K.; Webster, P.

    1987-05-01

    Dietary omega 3 fatty acids are thought to prevent atherosclerosis, possibly by modifying platelet (PT) function and arachidonic acid (20:4) metabolism. The study was designed to determine whether omega 3 fatty acids primarily affect 20:4 metabolism in megakaryocytes (MK), bone marrow precursors of PT, rather than in circulating PT. MK and PT were isolated from guinea pigs and incubated with (/sup 14/C)-20:4 (0.13uM). Docosahexaenoic acid (22:6) is a major omega 3 fatty acid in marine oils. The incubation of MK with 22:6 (0.1, 1.0 uM) resulted in the decrease of incorporation of (/sup 14/C)-20:4 into total MK phospholipids, 16% and 41% respectively. Alpha-linolenic acid (18:3), a major omega 3 fatty acid present in American diets, had no effect on 20:4 uptake in MK. 22:6 primarily affected the uptake of (/sup 14/C)-20:4 into phosphatidylethanolamine (PE) and phosphatidylserine (PS) in MK. In MK, 22:6 (0.1, 1.0 uM) caused a decrease of incorporation of (/sup 14/C)-20:4 into PE, 21% and 55% respectively; a decrease into PS, 16% and 48% respectively; but only a decrease of 4% and 18%, respectively, into phosphatidylcholine; and a decrease of 3% and 21% into phosphatidylinositol 22:6 (3.0 uM) had no effect on the uptake of AA into PT phospholipids. The study shows that 22:6 has a selective effect on AA uptake in MK and that the acylation or transacylation of PE and PS are primarily affected. 22:6 and other marine omega 3 fatty acids appear to primarily affect megakaryocytes which may result in the production of platelets with abnormal content and compartmentalization of AA.

  10. 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

  11. 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

  12. Maitotoxin: Effects on calcium channels, phosphoinositide breakdown, and arachidonate release in pheochromocytoma PC12 cells

    SciTech Connect

    Choi, O.H.; Padgett, W.L.; Nishizawa, Y.; Gusovsky, F.; Yasumoto, T.; Daly, J.W. )

    1990-02-01

    Maitotoxin (MTX) increases formation of (3H)inositol phosphates from phosphoinositides and release of (3H)arachidonic acid from phospholipids in pheochromocytoma PC12 cells. Formation of (3H)inositol phosphates is detected within 1 min of incubation even with concentrations as low as 0.3 ng/ml (90 pm) MTX, whereas release of (3H)arachidonic acid is not detected until 20 min even with concentrations as high as 1 ng/ml (300 pm) MTX. Stimulation of arachidonic acid release can be detected at 0.03 ng/ml (9 pm) MTX, whereas 0.1 ng/ml (30 pm) MTX is the threshold for detection of phosphoinositide breakdown. Organic and inorganic calcium channel blockers, except Cd2+ and a high concentration of Mn2+, have no effect on MTX-elicited phosphoinositide breakdown, whereas inorganic blockers (e.g., Co2+, Mn2+, Cd2+), but not organic blockers (nifedipine, verapamil, diltiazem), inhibit MTX-stimulated arachidonic acid release. All calcium channel blockers, however, inhibited MTX-elicited influx of 45Ca2+ and the MTX-elicited increase in internal Ca2+ measured with fura-2 was markedly reduced by nifedipine. MTX-elicited phosphoinositide breakdown and arachidonic acid release are abolished or reduced, respectively, in the absence of extracellular calcium plus chelating agent. The calcium ionophore A23187 has little or no effect alone but, in combination with MTX, A23187 inhibits MTX-elicited phosphoinositide breakdown and enhances arachidonic acid release, the latter even in the absence of extracellular calcium. The results suggest that different sites and/or mechanisms are involved in stimulation of calcium influx, breakdown of phosphoinositides, and release of arachidonic acid by MTX.

  13. Palmitic acid induces autophagy in hepatocytes via JNK2 activation

    PubMed Central

    Tu, Qian-qian; Zheng, Rui-ying; Li, Juan; Hu, Liang; Chang, Yan-xin; Li, Liang; Li, Min-hong; Wang, Ruo-yu; Huang, Dan-dan; Wu, Meng-chao; Hu, He-ping; Chen, Lei; Wang, Hong-yang

    2014-01-01

    Aim: Free fatty acid-induced lipotoxicity plays a crucial role in the progression of nonalcoholic fatty liver disease (NAFLD). In the present study we investigated the effects of a high-fat diet and free fatty acids on the autophagic process in hepatocytes in vivo and in vitro and the underlying mechanisms. Methods: LC3-II expression, a hallmark of autophagic flux, was detected in liver specimens from patients with non-alcoholic steatohepatitis (NASH) as well as in the livers of C57BL/6 mice fed a high-fat diet (HFD) up to 16 weeks. LC3-II expression was also analyzed in human SMMC-7721 and HepG2 hepatoma cells exposed to palmitic acid (PA), a saturated fatty acid. PA-induced apoptosis was detected by Annexin V staining and specific cleavage of PARP in the presence and absence of different agents. Results: LC3-II expression was markedly increased in human NASH and in liver tissues of HFD-fed mice. Treatment of SMMC-7721 cells with PA increased LC3-II expression in time- and dose-dependent manners, whereas the unsaturated fatty acid oleic acid had no effect. Inhibition of autophagy with 3MA sensitized SMMC-7721 cells to PA-induced apoptosis, whereas activation of autophagy by rapamycin attenuated PA-induced PARP cleavage. The autophagy-associated proteins Beclin1 and Atg5 were essential for PA-induced autophagy in SMMC-7721 cells. Moreover, pretreatment with SP600125, an inhibitor of JNK, effectively abrogated PA-mediated autophagy and apoptosis. Specific knockdown of JNK2, but not JNK1, in SMMC-7721 cells significantly suppressed PA-induced autophagy and enhanced its pro-apoptotic activity; whereas specific knockdown of JNK1 had the converse effect. Similar results were obtained when HepG2 cells were tested. Conclusion: JNK1 promotes PA-induced lipoapoptosis, whereas JNK2 activates pro-survival autophagy and inhibits PA lipotoxicity. Our results suggest that modulation of autophagy may have therapeutic benefits in the treatment of lipid-related metabolic diseases. PMID:24608675

  14. Unexpected depletion of plasma arachidonate and total protein in cats fed a low arachidonic acid diet due to peroxidation.

    PubMed

    Chamberlin, Amy; Mitsuhashi, Yuka; Bigley, Karen; Bauer, John E

    2011-10-01

    An opportunity to investigate a low-arachidonic acid (AA) feline diet possibly related to elevated peroxide value (PV) during storage on plasma phospholipid (PL) and reproductive tissue fatty acid (FA) profiles presented itself in the present study. Cats (nine animals per group) had been fed one of three dry extruded, complete and balanced diets for 300 d before spaying. The diets contained adequate AA (0.3 g/kg), similar concentration of antioxidants and were stored at ambient temperature, but differed in FA composition. The diets were designated as follows: diet A (high linoleic acid), diet B (high γ-linolenic acid) and diet C (adequate linoleic acid). Diet samples that were obtained the week before spaying revealed an elevated PV of diet A v. diets B and C (135 v. 5.80 and 2.12 meq/kg fat, respectively). Records revealed decreased food consumption of diet A cats beginning at 240 d but without weight loss; thus an opportunity presented to investigate diet PV effects. Total plasma protein and PL-AA concentrations in group A were significantly decreased at 140 and 300 d. Uterine and ovarian tissues collected at surgery revealed modest decrements of AA. Diet A was below minimum standards at 0.015 % (minimum 0.02 %), probably due to oxidation. The time at which diet A became unacceptable may have occurred between 60 and 140 d because plasma PL-AA was within our normal colony range (approximately 4-7 % relative) after 56 d of feeding. High-linoleic acid-containing diets may be more likely to be oxidised requiring additional antioxidants. The findings suggest that reduced plasma protein in combination with plasma AA concentrations may serve as biomarkers of diet peroxidation in cats before feed refusal, weight loss or tissue depletion. PMID:22005409

  15. 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…

  16. 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 Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An...

  17. 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 Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2710 Ear oximeter. (a) Identification. An...

  18. 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 Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification....

  19. Cutaneous lesions of the external ear

    PubMed Central

    Sand, Michael; Sand, Daniel; Brors, Dominik; Altmeyer, Peter; Mann, Benno; Bechara, Falk G

    2008-01-01

    Skin diseases on the external aspect of the ear are seen in a variety of medical disciplines. Dermatologists, othorhinolaryngologists, general practitioners, general and plastic surgeons are regularly consulted regarding cutaneous lesions on the ear. This article will focus on those diseases wherefore surgery or laser therapy is considered as a possible treatment option or which are potentially subject to surgical evaluation. PMID:18261212

  20. 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...

  1. 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 Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES GENERAL AND PLASTIC SURGERY DEVICES Prosthetic Devices § 878.3590 Ear prosthesis. (a) Identification....

  2. 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

  3. The resistance of glyoxylic acid induced catecholamine fluorescence to sodium borohydride reduction.

    PubMed

    Waris, T; Liesi, P; Panula, P; Partanen, S

    1982-01-01

    The borohydride reduction of glyoxylic acid induced fluorescence in noradrenergic and DOPA-minergic nervous structures and in amines in model experiments was studied. Both DOPAmine and noradrenaline fluorescences were resistant to borohydride reduction differing thus from the formaldehyde-induced fluorescence. Thus when the specificity of glyoxylic acid induced fluorescence is in doubt, other tests than borohydride reduction of the fluorescence must be employed. PMID:6815962

  4. Essentiality of arachidonic acid intake in murine early development.

    PubMed

    Hatanaka, Erisa; Harauma, Akiko; Yasuda, Hidemi; Watanabe, Junnosuke; Nakamura, Manabu T; Salem, Norman; Moriguchi, Toru

    2016-05-01

    We previously reported the importance of long-chain polyunsaturated fatty acid (LC-PUFA (>C20)) intake, including arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), for growth. This follow-up study focuses on ARA using a novel artificial rearing model during the lactation period in delta-6-desaturase knockout (D6D-KO) mice. Newborn D6D-KO male mouse pups were separated from dams within 48 hours and fed artificial milks containing 18-C essential fatty acids (EFAs) (16-17% LA, 3.8-4.1% ALA) with or without 1.2% ARA. After weaning, mice were maintained on similar diets: 15% LA, 2.3-2.4% ALA with or without 1.9% ARA. As a reference group, new born wild type (WT) male mouse pups were maintained by artificial milk and diet containing LA and ALA without ARA. Aspects of brain function were measured behaviorally (motor activity and rota-rod test) when mice were age 9 weeks. Body weight in the KO-Cont group was significantly lower (approximately 30%) than in the WT-Cont group, but this decrease was ameliorated by providing ARA in the KO-ARA group. The motor activity and coordination in the KO-Cont group decreased markedly compared to the WT-Cont group. The KO-ARA group had a tendency toward deteriorated motor coordination, although the motor activity was significantly enhanced compared to the KO-Cont group. In KO-ARA group brains, the level of ARA was increased and DHA decreased compared to WT-Cont. These results suggest that intake of LA and ALA only is insufficient to support healthy growth, and that ARA is also required, at least during the lactation period. These findings also suggested that continued intake of relatively high levels of ARA and without supplemental DHA during development led to an increased motor activity above that of WT animals. These studies indicate that both ARA dose and proper combination with DHA must be delineated to define optimal growth and behavioral function. PMID:27154365

  5. Hepatic arachidonic acid metabolism is disrupted after hexachlorobenzene treatment.

    PubMed

    Billi de Catabbi, Silvia C; Faletti, Alicia; Fuentes, Federico; San Martín de Viale, Leonor C; Cochón, Adriana C

    2005-04-15

    Hexaclorobenzene (HCB), one of the most persistent environmental pollutants, can cause a wide range of toxic effects including cancer in animals, and hepatotoxicity and porphyria both in humans and animals. In the present study, liver microsomal cytochrome P450 (CYP)-dependent arachidonic acid (AA) metabolism, hepatic PGE production, and cytosolic phospholipase A2 (cPLA2) activity were investigated in an experimental model of porphyria cutanea tarda induced by HCB. Female Wistar rats were treated with a single daily dose of HCB (100 mg kg(-1) body weight) for 5 days and were sacrificed 3, 10, 17, and 52 days after the last dose. HCB treatment induced the accumulation of hepatic porphyrins from day 17 and increased the activities of liver ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), and aminopyrine N-demethylase (APND) from day 3 after the last dose. Liver microsomes from control and HCB-treated rats generated, in the presence of NADPH, hydroxyeicosatetraenoic acids (HETEs), epoxyeicosatrienoic acids (EETs), 11,12-Di HETE, and omega-OH/omega-1-OH AA. HCB treatment caused an increase in total NADPH CYP-dependent AA metabolism, with a higher response at 3 days after the last HCB dose than at the other time points studied. In addition, HCB treatment markedly enhanced PGE production and release in liver slices. This HCB effect was time dependent and reached its highest level after 10 days. At this time cPLA2 activity was shown to be increased. Unexpectedly, HCB produced a significant decrease in cPLA2 activity on the 17th and 52nd day. Our results demonstrated for the first time that HCB induces both the cyclooxygenase and CYP-dependent AA metabolism. The effects of HCB on AA metabolism were previous to the onset of a marked porphyria and might contribute to different aspects of HCB-induced liver toxicity such as alterations of membrane fluidity and membrane-bound protein function. Observations also suggested that a possible role of cPLA2 in the early increase of AA metabolism cannot be excluded. However, the existence of other pathway(s) for metabolizable AA generation different from cPLA2 activation is also proposed. PMID:15808524

  6. The alpha 1-adrenergic transduction system in hamster brown adipocytes. Release of arachidonic acid accompanies activation of phospholipase C.

    PubMed Central

    Schimmel, R J

    1988-01-01

    Previous studies of brown adipocytes identified an increased breakdown of phosphoinositides after selective alpha 1-adrenergic-receptor activation. The present paper reports that this response, elicited with phenylephrine in the presence of propranolol and measured as the accumulation of [3H]inositol phosphates, is accompanied by increased release of [3H]arachidonic acid from cells prelabelled with [3H]arachidonic acid. Differences between stimulated arachidonic acid release and formation of inositol phosphates included a requirement for extracellular Ca2+ for stimulated release of arachidonic acid but not for the formation of inositol phosphates and the preferential inhibition of inositol phosphate formation by phorbol 12-myristate 13-acetate. The release of arachidonic acid in response to phenylephrine was associated with an accumulation of [3H]arachidonic acid-labelled diacylglycerol, and this response was not dependent on extracellular Ca2+ but was partially prevented by treatment with the phorbol ester. The release of arachidonic acid was also stimulated by melittin, which increases the activity of phospholipase A2, by ionophore A23187, by lipolytic stimulation with forskolin and by exogenous phospholipase C. The arachidonic acid response to phospholipase C was completely blocked by RHC 80267, an inhibitor of diacylglycerol lipase, but this inhibitor had no effect on release stimulated with melittin or A23187 and inhibited phenylephrine-stimulated release by only 40%. The arachidonate response to forskolin was additive with the responses to either phenylephrine or exogenous phospholipase C. These data indicate that brown adipocytes are capable of releasing arachidonic acid from neutral lipids via triacylglycerol lipolysis, and from phospholipids via phospholipase A2 or by the sequential activities of phospholipase C and diacylglycerol lipase. Our findings also suggest that the action of phenylephrine to promote the liberation of arachidonic acid utilizes both of these reactions. PMID:3138988

  7. Numerical analysis of ossicular chain lesion of human ear

    NASA Astrophysics Data System (ADS)

    Liu, Yingxi; Li, Sheng; Sun, Xiuzhen

    2009-04-01

    Lesion of ossicular chain is a common ear disease impairing the sense of hearing. A comprehensive numerical model of human ear can provide better understanding of sound transmission. In this study, we propose a three-dimensional finite element model of human ear that incorporates the canal, tympanic membrane, ossicular bones, middle ear suspensory ligaments/muscles, middle ear cavity and inner ear fluid. Numerical analysis is conducted and employed to predict the effects of middle ear cavity, malleus handle defect, hypoplasia of the long process of incus, and stapedial crus defect on sound transmission. The present finite element model is shown to be reasonable in predicting the ossicular mechanics of human ear.

  8. Benzodiazepine analogues inhibit arachidonate-induced aggregation and thromboxane synthesis in human platelets.

    PubMed Central

    Fonlupt, P.; Croset, M.; Lagarde, M.

    1990-01-01

    1. Benzodiazepine analogues inhibit human platelet aggregation induced by arachidonate with an EC50 value of 0.68 microM for PK 11195, the most potent analogue used. 2. There was a highly significant correlation between the inhibition of arachidonate-induced aggregation and the affinity for the peripheral-type of benzodiazepine binding sites. 3. There was no significant correlation between the inhibition of the platelet activating factor (PAF)-induced aggregation and the binding to the peripheral-type of benzodiazepine binding sites. 4. The inhibition of platelet aggregation seems to result from the inhibition of arachidonic acid cyclo-oxygenation, since the synthesis of thromboxane and 12-hydroxy-heptadecatrienoic acid, both cyclo-oxygenase products, was reduced. 5. Our results suggest that peripheral-type of benzodiazepine binding sites on human platelets could be linked to cyclo-oxygenase. PMID:1964822

  9. 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.

  10. Changes in arachidonic acid metabolism in UV-irradiated hairless mouse skin

    SciTech Connect

    Ruzicka, T.; Walter, J.F.; Printz, M.P.

    1983-10-01

    This study was conducted to investigate the metabolism of arachidonic acid in the skin of hairless mice exposed to UVA, PUVA, UVB, and UVC irradiation. The main products of arachidonic acid in the epidermis were hydroxyeicosatetraenoic acid (HETE), PGE2, and PGD2. Dermis displayed a lower lipoxygenase activity (expressed as HETE production) than the epidermis and showed no detectable cyclooxygenase activity, i.e., no prostaglandin production. The main changes observed in UV-induced inflammatory reactions were as follows. 1. A 5-fold increase in dermal HETE production in PUVA-treated animals and a 29% reduction in epidermal HETE formation after UVC treatment. 2. A marked decrease of PGD2 and a marked increase of PGE2 formation due to alterations of PGH2 metabolism in the UVB-treated group; however, cyclooxygenase activity was unchanged. These changes in arachidonic acid metabolism in the skin may be of pathophysiologic importance in UV-induced inflammatory reaction.

  11. 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

  12. 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.

  13. 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

  14. 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.

  15. Effects of compounds in leaves of Salix matsudana on arachidonic acid metabolism.

    PubMed

    Zheng, Yi-Nan; Zhang, Jing; Han, Li-Kun; Sekiya, Keizo; Kimura, Yoshiyuki; Okuda, Hiromichi

    2005-12-01

    Apigenin 7-O-beta-D-glucopyranuronide (1), luteolin 7-O-beta-D-glucopyranuronide (2), m-hydroxybenzyl beta-D-glucoside (3), and chrysoeriol 7-O-beta-D-glucopyranuronide (4) were isolated for the first time from the leaves of Salix matsudana. Furthermore, the effects of compounds 1, 2 and 3 on arachidonic acid metabolism were studied. These compounds inhibited significantly the production of 12-hydroxy-5, 8, 10, 14-eicosatetraenoic acid (12-HETE). In addition, the aglycon apigenin inhibited not only 12-HETE but also thromboxane B(2) (TXB(2)). The effect of compound (4) on arachidonic acid metabolism is now under investigation. PMID:16327246

  16. 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 ℛ 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 ℛ 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 ℛ, 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 ℛ. 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 ℛ were minimal when a smaller fraction of the air space was filled with fluid, and as the air space was filled with more saline, ℛ increased at most frequencies. Fixation of the stapes generally resulted in a relatively small low-frequency increase in ℛ. Disarticulation of the incus with the stapes led to a consistent low-frequency decreases in ℛ with a distinctive minimum below 1000 Hz. Perforations of the tympanic membrane resulted in a decrease in ℛ 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

  17. Ear cleaning: the UK and US perspective.

    PubMed

    Nuttall, Tim; Cole, Lynette K

    2004-04-01

    Ear cleaning helps maintain the normal otic environment and is important in the treatment of otitis. Over cleaning, however, may trigger otitis through maceration of the epidermal lining. Simple manual cleaning is useful for routine cleansing but doesn't remove tightly adherent debris. Bulb syringes are more vigorous but may damage the ear in inexperienced hands. Devices using mains water pressure or dental machines are also available. Thorough cleaning of the ear canals and middle ear cavity can only be achieved by retrograde flushing using specially adapted catheters, feeding tubes or video otoscopes under anaesthesia. Myringotomy, inspection and cleaning of the middle should be performed if the tympanic membrane appears abnormal. There are a wide variety of cleaning fluids available. Ceruminolytics soften and dissolve cerumen to facilitate cleaning. Surfactants emulsify debris, breaking it up and keeping it in solution. Astringents dry the ear canal surface, preventing maceration. Maintaining a low pH and incorporating antimicrobial agents can inhibit microbial proliferation and glucocorticoids can be used to reduce inflammation. Adverse effects and contraindications following ear cleaning can include maceration, contact reactions, otitis media, ear canal avulsion, vestibular syndrome, Horner's syndrome, facial nerve paralysis and deafness. Care should be exercised in selecting cleaning fluids if the tympanic membranes are ruptured. PMID:15030561

  18. 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

  19. Gouty tophi on the ear: a review.

    PubMed

    Chabra, Indy; Singh, Rajendra

    2013-10-01

    Although the classic location of gouty tophi is the great toe (podagra), gouty tophi of the ear also is common and is worth including in the differential diagnosis in patients presenting with ear lesions. Other entities presenting as papules or nodules on the ear include chondrodermatitis nodularis helicis (CNH), actinic keratosis, basal cell carcinoma, squamous cell carcinoma, verruca vulgaris, amyloids, rheumatoid nodules, and elastotic nodules. If tophaceous gout is suspected, alcohol fixation of the biopsy specimen is preferable, as it enables visualization of characteristic needle-shaped urate crystals. PMID:24195091

  20. 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

  1. Directional Sensitivity of the Human Ear.

    ERIC Educational Resources Information Center

    Pitt, John D.; Bazley, Martin

    1985-01-01

    Presents a classroom experiment that demonstrates the directional sensitivity of the human ear. Outlines the activity's procedures and provides a diagrammatical view of the experimental arrangement. Also included is an analysis of the expected results. (ML)

  2. Ear, Nose & Throat Issues & Down Syndrome

    MedlinePlus

    ... Series Videos Webinar Series Health Care Associated Conditions ADHD & Down Syndrome Alzheimer's Disease & Down Syndrome Anesthesia & Down Syndrome Atlantoaxial Instability & Down Syndrome Blood Diseases & Down Syndrome Dental Issues & Down Syndrome Dual Diagnosis of Down Syndrome & Autism Ear, Nose & Throat Issues & ...

  3. Neonatal Ear Molding: Timing and Technique.

    PubMed

    Anstadt, Erin Elizabeth; Johns, Dana Nicole; Kwok, Alvin Chi-Ming; Siddiqi, Faizi; Gociman, Barbu

    2016-03-01

    The incidence of auricular deformities is believed to be ∼11.5 per 10 000 births, excluding children with microtia. Although not life-threatening, auricular deformities can cause undue distress for patients and their families. Although surgical procedures have traditionally been used to reconstruct congenital auricular deformities, ear molding has been gaining acceptance as an efficacious, noninvasive alternative for the treatment of newborns with ear deformations. We present the successful correction of bilateral Stahl's ear deformity in a newborn through a straightforward, nonsurgical method implemented on the first day of life. The aim of this report is to make pediatric practitioners aware of an effective and simple molding technique appropriate for correction of congenital auricular anomalies. In addition, it stresses the importance of very early initiation of ear cartilage molding for achieving the desired outcome. PMID:26908661

  4. [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

  5. 14 CFR 67.105 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (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 airman... Better ear (Db) 35 30 30 40 Poorer ear (Db) 35 50 50 60 (b) No disease or condition of the middle...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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...

  18. Use of Metabolomic Profiling in the Study of Arachidonic Acid Metabolism in Cardiovascular Disease

    PubMed Central

    Li, Ning; Liu, Jun-Yan; Qiu, Hong; Harris, Todd R.; Sirish, Padmini; Hammock, Bruce D.; Chiamvimonvat, Nipavan

    2013-01-01

    Arachidonic acid is one of the pivotal signaling molecules associated with inflammation, pain and homeostatic function. Drugs specifically targeting these signaling pathways represent more than 25% of annual pharmaceutical sales worldwide. However, chronic administration of nonsteroidal anti-inflammatory drugs (NSAIDs) and rofecoxib (Vioxx), a potent cyclooxygenase-2 inhibitor, have been associated with adverse cardiovascular events. Understanding the possible mechanisms underlying these adverse events is critical for evaluating the risks and benefits of this group of drugs and for development of safer drugs. Using a powerful metabolomics approach, 20-hydroxyeicosatetraenoic acid (20-HETE) was identified among many of arachidonic acid metabolic products as a likely culprit for adverse cardiovascular side effect associated with rofecoxib and NSAIDs. In addition, using a similar metabolomic approach, epoxyeicosatrienoic acids (EETs), which are lipid mediators derived from arachidonic acid through the cytochrome P450 epoxygenase pathway, have been shown to exhibit cardioprotective effects in a murine myocardial infarction (MI) model. Inhibitors of the soluble epoxide hydrolase increase titers of epoxy fatty acids and both block and reverse cardiac hypertrophy in rodent models. These highly potent, orally available compounds may be promising for treating heart failure and other cardiovascular disease. In this review, we will summarize some of the recent advances using metabolomic profiling to gain insights into the involvement of arachidonic acid pathways in cardiovascular disease. PMID:21272227

  19. 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...

  20. 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

  1. Activated rat neutrophils. Correlation of arachidonate products with enzyme secretion but not with O(2)- generation.

    PubMed Central

    Ward, P. A.; Sulavik, M. C.; Johnson, K. J.

    1985-01-01

    Functional responses (enzyme secretion and generation of O2-) have been studied in rat neutrophils with the use of a variety of different agonists which vary in their ability to activate neutrophils. Concomitantly, the authors have analyzed the cells for production of cyclooxygenase (PGE2, PGF2 alpha, and TXB2) and lipoxygenase (monoHETEs and LTB4) products in order to determine whether there is a correlation between functional responses and arachidonate products in stimulated neutrophils. The studies indicate that enzyme secretion is closely correlated with generation of arachidonate (cyclooxygenase as well as lipoxygenase) products. These responses are dependent on the dose of agonist employed, but there does not appear to be a unique pattern of arachidonate products that can be attributed to a specific agonist. With respect to monohydroxyeicosatetraenoic acid (monoHETE) generation, we demonstrate that stimulated rat neutrophils selectively produce 5-HETE, to the virtual exclusion of 12-HETE and 15-HETE. The production of O2- from stimulated rat neutrophils is correlated neither with enzyme secretion nor with the generation of arachidonate products. These studies suggest that enzyme secretion and O2- generation are mediated by two fundamentally different intracellular pathways, even though these functional responses probably derive from common agonist-receptor interactions on the plasma membrane. PMID:2990221

  2. 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...

  3. Trans-arachidonic acids generated during nitrative stress induce a thrombospondin-1-dependent microvascular degeneration

    PubMed Central

    Kermorvant-Duchemin, Elsa; Sennlaub, Florian; Sirinyan, Mirna; Brault, Sonia; Andelfinger, Gregor; Kooli, Amna; Germain, Stéphane; Ong, Huy; D'Orleans-Juste, Pedro; Gobeil, Fernand; Zhu, Tang; Boisvert, Chantal; Hardy, Pierre; Jain, Kavita; Falck, John; Balazy, Michael; Chemtob, Sylvain

    2005-01-01

    Nitrative stress has an important role in microvascular degeneration leading to ischemia in conditions such as diabetic retinopathy and retinopathy of prematurity. Thus far, mediators of nitrative stress have been poorly characterized. We recently described that trans-arachidonic acids are major products of NO2•-mediated isomerization of arachidonic acid within the cell membrane, but their biological relevance is unknown. Here we show that trans-arachidonic acids are generated in a model of retinal microangiopathy in vivo in a NO•-dependent manner. They induce a selective time- and concentration-dependent apoptosis of microvascular endothelial cells in vitro, and result in retinal microvascular degeneration ex vivo and in vivo. These effects are mediated by an upregulation of the antiangiogenic factor thrombospondin-1, independently of classical arachidonic acid metabolism. Our findings provide new insight into the molecular mechanisms of nitrative stress in microvascular injury and suggest new therapeutic avenues in the management of disorders involving nitrative stress, such as ischemic retinopathies and encephalopathies. PMID:16311602

  4. Identification of an Arachidonic Acid-Producing Bacterium and Description of Kineococcus arachidonicus sp. nov.

    SciTech Connect

    Fliermans, C.B.

    2001-05-15

    The identification of bacterial with the ability to produce polyunsaturated fatty acids as been limited almost exclusively to gram-negative, psychrophilic, marine microorganisms. Here we describe a new gram-type-positive bactgerium, strain SRS30216T, that produces the polyunsaturated fatty acid, arachidonic acid, and is neither psychrophilic nor a marine isolate.

  5. 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.

  6. 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

  7. 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

  8. 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

  9. Predictions of middle-ear and passive cochlear mechanics using a finite element model of the pediatric ear.

    PubMed

    Wang, Xuelin; Keefe, Douglas H; Gan, Rong Z

    2016-04-01

    A finite element (FE) model was developed based on histological sections of a temporal bone of a 4-year-old child to simulate middle-ear and cochlear function in ears with normal hearing and otitis media. This pediatric model of the normal ear, consisting of an ear canal, middle ear, and spiral cochlea, was first validated with published energy absorbance (EA) measurements in young children with normal ears. The model was used to simulate EA in an ear with middle-ear effusion, whose results were compared to clinical EA measurements. The spiral cochlea component of the model was constructed under the assumption that the mechanics were passive. The FE model predicted middle-ear transfer functions between the ear canal and cochlea. Effects of ear structure and mechanical properties of soft tissues were compared in model predictions for the pediatric and adult ears. EA responses are predicted to differ between adult and pediatric ears due to differences in the stiffness and damping of soft tissues within the ear, and any residual geometrical differences between the adult ear and pediatric ear at age 4 years. The results have significance for predicting effects of otitis media in children. PMID:27106321

  10. 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

  11. Comparison of ear tattoo, ear notching and microtattoo in rats undergoing cardiovascular telemetry.

    PubMed

    Kasanen, I H E; Voipio, H-M; Leskinen, H; Luodonpää, M; Nevalainen, T O

    2011-07-01

    Individual and permanent identification of experimental animals is a common and often essential research practice. There is little information available on the short-term effects of these procedures on the animals. In this study, seven rats were implanted with telemetric devices. The effects of three different identification methods (ear tattoo, ear notching and microtattoo) were compared. Cardiovascular data were collected for 24 h after the procedures. Time periods of 0-1, 1-4, 4-16 h (dark) and 16-24 h after the procedure were analysed separately. The most pronounced differences in measured parameters were observed during the first hour after the procedures were performed. Mean arterial pressure (MAP) was significantly higher (P < 0.012) following the ear tattoo than the microtattoo procedure by a difference of approximately 5 mmHg. Heart rate (HR) was significantly elevated (P < 0.001) after ear tattoo compared with both ear notching (Δ = 31 beats per minute [bpm]) and microtattoo (Δ = 44 bpm). During the 1-4 h period and the following dark period, the MAP was highest in the ear notching group, but no differences were observed in the HRs. During the following dark period (4-16 h) and the next day (16-24 h) differences in MAP and HR were minor. In conclusion, microtattoo appears to cause the mildest changes in HR and blood pressure. Based on these results, ear tattoo and ear notching should be replaced by microtattoo whenever possible. PMID:21504993

  12. 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

  13. 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...

  14. 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

  15. 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

  16. 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

  17. Passive and active middle ear implants

    PubMed Central

    Beutner, Dirk; Hüttenbrink, 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

  18. 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.

  19. "Petrified Ears" in Secondary Adrenal Insufficiency.

    PubMed

    Goswami, Soumik; Chakraborty, Partha Pratim; Ray, Sayantan; Ghosh, Sujoy; Chowdhury, Subhankar

    2016-02-01

    Petrification of the auricle, a rarely encountered clinical entity usually results from ectopic calcification of the auricular cartilages and manifests as rigid ear. The underlying pathogenesis remains ambiguous with several proposed hypotheses till date. Auricular calcification may be the sole cutaneous marker of underlying endocrinopathy at times. Adrenal insufficiency is the most common endocrinological disorder to be associated with such stiff ears and it has been described in both primary as well as secondary forms of the disease. We present here a 30-year-old man whose clinical condition deteriorated following levothyroxine supplementation and the presence of "petrified ears" ultimately provided a clue to the diagnosis of associated secondary adrenal insufficiency. PMID:27042511

  20. [Bone Conduction and Active Middle Ear Implants].

    PubMed

    Volkenstein, S; Thomas, J P; Dazert, S

    2016-05-01

    The majority of patients with moderate to severe hearing loss can be supplied with conventional hearing aids depending on severity and cause for hearing loss in a satisfying way. However, some patients either do not benefit enough from conventional hearing aids or cannot wear them due to inflammatory reactions and chronic infections of the external auditory canal or due to anatomical reasons. For these patients there are fully- and semi-implantable middle ear and bone conduction implants available. These devices either directly stimulate the skull (bone conduction devices), middle ear structures (active middle ear implants) or the cochlea itself (direct acoustic stimulation). Patients who failed surgical hearing rehabilitation or do not benefit from conventional hearing aids may achieve a significant better speech understanding and tremendous improvement in quality of life by implantable hearing devices with careful attention to the audiological and anatomical indication criteria. PMID:27135430

  1. 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

  2. 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.

  3. Effect of dietary fish oil on platelet aggregability: comparison between two oils with different eicosapentaenoic to arachidonic acid ratio.

    PubMed

    Bandyopadhyay, I; Saha, S; Dutta, J

    1991-12-01

    Rats, acclimatized on a control diet, were fed for 60 days with diets, supplemented with 10% fat of either marine Hilsa fish (Hilsa ilisa) or fresh-water Chital fish (Notopterus chitala). The percentage of eicosapentaenoic acid in chital oil diet was 0.57 times that of the hilsa oil diet, but the eicosapentaenoic to arachidonic acid ratio in the latter (4.08) was 3.2 times that of the former (1.27). Otherwise these two diets were comparable in respect to total saturated, monounsaturated and n-3 polyunsaturated fatty acid contents. Results showed that of the two only hilsa oil diet could significantly lower platelet aggregability and in vitro thromboxane production, through replacement of arachidonic acid in platelet phospholipid by eicosapentaenoic acid. The antithrombic criteria of the oil seems to be a combination of low arachidonic acid content and high eicosapentaenoic to arachidonic acid ratio. PMID:1804110

  4. 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.

  5. 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

  6. The role of arachidonic acid metabolism in virus-induced alveolar macrophage dysfunction

    SciTech Connect

    Laegreid, W.W.

    1988-01-01

    Alveolar macrophages (AM) recovered from virus-infected lungs have decreased phagocytic, respiratory burst and bactericidal activities. The studies described below investigated the role of eicosanoids in virus induced AM bactericidal dysfunction. The spectrum of eicosanoid metabolites which bovine AM are capable of producing was determined. Cultured AM were exposed to {sup 3}H-arachidonate for 1 hour, stimulated for 4 hours with A23187, phorbol myristate acetate or zymosan and the supernatants extracted and analyzed by HPLC. All stimuli tested caused the release of these cyclooxygenase metabolites: thromboxane B{sub 2}, PGF{sub 2}, PGE{sub 2}, PGD{sub 2} and HHT. The effect of this enhanced release of arachidonate metabolites on the ability of AM to kill bacteria was evaluated. Preincubation with cyclooxygenase inhibitors or dual cyclooxygenase and lipoxygenase inhibitors resulted in partial reversal of the virus-induced bactericidal deficit in PI3 infected AM.

  7. Effects of arachidonic acid on unitary calcium currents in rat sympathetic neurons

    PubMed Central

    Liu, Liwang; Rittenhouse, Ann R

    2000-01-01

    We have characterized the actions of arachidonic acid (AA) on whole cell and unitary calcium (Ca2+) currents in rat neonatal superior cervical ganglion (SCG) neurons using barium (Ba2+) as the charge carrier. Whole cell currents were elicited by stepping the membrane potential from −90 mV to +10 mV. Arachidonic acid (5 μm) was introduced into the bath in the continued presence of 1 μm (+)-202-791, an L-type Ca2+ channel agonist. Under these conditions, the peak current, comprised mainly of N-type current, and a slow, (+)-202-791-induced component of the tail current were inhibited by 67 ± 6 and 60 ± 10%, respectively, indicating that AA inhibits both N- and L-type currents. At a test potential of +30 mV, AA (5 μm) decreased unitary L- and N-type Ca2+ channel open probability (Po) in cell-attached patches that contained a single channel. For both channels, the underlying causes of the decrease in Po were similar. Arachidonic acid caused an increase in the percentage of null sweeps and in the number of null sweeps that clustered together. In sweeps with activity, the average number of openings per sweep decreased, while first latency and mean closed time increased. Arachidonic acid had no significant effect on unitary current amplitude or mean open time. Our findings are the first description of the inhibition of unitary L- and N-type Ca2+ channel activity by AA and are consistent with both channels spending more time in their null mode and with increased dwell time in one or more closed states. PMID:10835042

  8. 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.

  9. 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

  10. 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.

  11. 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

  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. Factors Affecting the Elicitation of Sesquiterpenoid Phytoalexin Accumulation by Eicosapentaenoic and Arachidonic Acids in Potato 1

    PubMed Central

    Bostock, Richard M.; Laine, Roger A.; Kuć, Joseph A.

    1982-01-01

    Eicosapentaenoic and arachidonic acids in extracts of Phytophthora infestans mycelium were identified as the most active elicitors of sesquiterpenoid phytoalexin accumulation in potato tuber slices. These fatty acids were found free or esterified in all fractions with elicitor activity including cell wall preparations. Yeast lipase released a major portion of eicosapentaenoic and arachidonic acids from lyophilized mycelium. Concentration response curves comparing the elicitor activity of the polyunsaturated fatty acids to a cell-free sonicate of P. infestans mycelium indicated that the elicitor activity of the sonicated mycelium exceeded that which would be obtained by the amount of eicosapentaenoic and arachidonic acids (free and esterified) present in the mycelium. Upon acid hydrolysis of lyophilized mycelium, elicitor activity was obtained only from the fatty acid fraction. However, the fatty acids accounted for only 21% of the activity of the unhydrolyzed mycelium and the residue did not enhance their activity. Centrifugation of the hydrolysate, obtained from lyophilized mycelium treated with 2n NaOH, 1 molarity NaBH4 at 100°C, yielded a supernatant fraction with little or no elicitor activity. Addition of this material to the fatty acids restored the activity to that which was present in the unhydrolyzed mycelium. The results indicate that the elicitor activity of the unsaturated fatty acids is enhanced by heat and base-stable factors in the mycelium. PMID:16662691

  14. Strategies for Individual Phenotyping of Linoleic and Arachidonic Acid Metabolism Using an Oral Glucose Tolerance Test

    PubMed Central

    Saccenti, Edoardo; van Duynhoven, John; Jacobs, Doris M.; Smilde, Age K.; Hoefsloot, Huub C. J.

    2015-01-01

    The ability to restore homeostasis upon environmental challenges has been proposed as a measure for health. Metabolic profiling of plasma samples during the challenge response phase should offer a profound view on the flexibility of a phenotype to cope with daily stressors. Current data modeling approaches, however, struggle to extract biological descriptors from time-resolved metabolite profiles that are able to discriminate between different phenotypes. Thus, for the case of oxylipin responses in plasma upon an oral glucose tolerance test we developed a modeling approach that incorporates a priori biological pathway knowledge. The degradation pathways of arachidonic and linoleic acids were modeled using a regression model based on a pseudo-steady-state approximated model, resulting in a parameter A that summarizes the relative enzymatic activity in these pathways. Analysis of the phenotypic parameters As suggests that different phenotypes can be discriminated according to preferred relative activity of the arachidonic and linoleic pathway. Correlation analysis shows that there is little or no competition between the arachidonic and linoleic acid pathways, although they share the same enzymes. PMID:25786212

  15. 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.

  16. 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

  17. 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 ...

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

    MedlinePlus

    ... Calendar Find an ENT Doctor Near You Pediatric Obesity and Ear, Nose, and Throat Disorders Pediatric Obesity ... self-esteem, and isolation from their peers. Pediatric obesity and otolaryngic problems Otolaryngologists, or ear, nose, and ...

  19. 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

  20. 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.

  1. 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…

  2. Play It by Ear. Hearing Conservation Curriculum.

    ERIC Educational Resources Information Center

    Olson, Dianne R.

    This curriculum was designed to help teachers teach their fourth-grade students about hearing and the effects of loud noises on hearing. The program describes the human ear and how it works, explains the health effects of noise, and offers ways for students to protect their hearing from unsafe noise levels. Students are taught how hearing is…

  3. Lewis Thomas and droopy rabbit ears

    PubMed Central

    Bashyam, Hema

    2007-01-01

    In 1956, Lewis Thomas discovered that injecting rabbits with a plant protease called papain caused their ears to collapse. This experiment led to the identification of the endogenous proteases that cause the tissue destruction seen in diseases such as rheumatoid arthritis.

  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

    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. Ear Infections - Multiple Languages: MedlinePlus

    MedlinePlus

    ... on this page, please enable JavaScript. French (français) Japanese (日本語) Korean (한국어) Russian (Русский) Somali (af Soomaali) ... moyenne - français (French) Bilingual PDF Health Information Translations Japanese (日本語) Middle Ear Infection 中耳炎 - 日本語 (Japanese) Bilingual ...

  7. The formation and management of middle ear granulation tissue in chronic ear disease.

    PubMed

    Roland, Peter S

    2004-01-01

    Granulation tissue is an important pathogenic feature of all types of chronic ear disease, and it can be controlled and treated with good aural toilet, appropriate antibiotic therapy, topical steroids, and chemical cautery or surgical debridement. PMID:14986396

  8. 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

  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. 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 874.4140 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4140 Ear, nose, and throat bur....

  11. 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 874.4140 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Surgical Devices § 874.4140 Ear, nose, and throat bur....

  12. 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...

  13. 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 and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification....

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

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (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 airman...) 35 50 50 60 (b) No disease or condition of the middle or internal ear, nose, oral cavity, pharynx,...

  15. 14 CFR 67.305 - Ear, nose, throat, and equilibrium.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... (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 airman...) 35 50 50 60 (b) No disease or condition of the middle or internal ear, nose, oral cavity, pharynx,...

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  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. 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...

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. Acid-inducible proton influx currents in the plasma membrane of murine osteoclast-like cells.

    PubMed

    Kuno, Miyuki; Li, Guangshuai; Moriura, Yoshie; Hino, Yoshiko; Kawawaki, Junko; Sakai, Hiromu

    2016-05-01

    Acidification of the resorption pits, which is essential for dissolving bone, is produced by secretion of protons through vacuolar H(+)-ATPases in the plasma membrane of bone-resorbing cells, osteoclasts. Consequently, osteoclasts face highly acidic extracellular environments, where the pH gradient across the plasma membrane could generate a force driving protons into the cells. Proton influx mechanisms during the acid exposure are largely unknown, however. In this study, we investigated extracellular-acid-inducible proton influx currents in osteoclast-like cells derived from a macrophage cell line (RAW264). Decreasing extracellular pH to <5.5 induced non-ohmic inward currents. The reversal potentials depended on the pH gradients across the membrane and were independent of concentrations of Na(+), Cl(-), and HCO3 (-), suggesting that they were carried largely by protons. The acid-inducible proton influx currents were not inhibited by amiloride, a widely used blocker for cation channels/transporters, or by 4,4'-diisothiocyanato-2,2'-stilbenesulfonate(DIDS) which blocks anion channels/transporters. Additionally, the currents were not significantly affected by V-ATPase inhibitors, bafilomycin A1 and N,N'-dicyclohexylcarbodiimide. Extracellular Ca(2+) (10 mM) did not affect the currents, but 1 mM ZnCl2 decreased the currents partially. The intracellular pH in the vicinity of the plasma membrane was dropped by the acid-inducible H(+) influx currents, which caused overshoot of the voltage-gated H(+) channels after removal of acids. The H(+) influx currents were smaller in undifferentiated, mononuclear RAW cells and were negligible in COS7 cells. These data suggest that the acid-inducible H(+) influx (H(+) leak) pathway may be an additional mechanism modifying the pH environments of osteoclasts upon exposure to strong acids. PMID:26843093

  14. 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

  15. 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

  16. 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

  17. Treatment of Prominent Ears and Otoplasty: A Contemporary Review.

    PubMed

    Pawar, Sachin S; Koch, Cody A; Murakami, Craig

    2015-01-01

    Prominent ears affect approximately 5% of the population and can have a significant psychological impact on patients. A wide variety of otoplasty techniques have been described, all sharing the goal of re-creating the normal appearance of the ear and achieving symmetry between the 2 sides. Recent trends in otoplasty techniques have consistently moved toward less invasive options, ranging from nonsurgical newborn ear molding to cartilage-sparing surgical techniques and even incisionless, office-based procedures. Herein, we review anatomy of the external ear, patient evaluation, the evolution of nonsurgical and surgical otoplasty techniques, otoplasty outcomes, and future trends for treatment of prominent ears. PMID:26158729

  18. 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.

  19. Inhibition of arachidonate 5-lipoxygenase triggers massive apoptosis in human prostate cancer cells

    PubMed Central

    Ghosh, Jagadananda; Myers, Charles E.

    1998-01-01

    Diets high in fat are associated with an increased risk of prostate cancer, although the molecular mechanism is still unknown. We have previously reported that arachidonic acid, an omega-6 fatty acid common in the Western diet, stimulates proliferation of prostate cancer cells through production of the 5-lipoxygenase metabolite, 5-HETE (5-hydroxyeicosatetraenoic acid). We now show that 5-HETE is also a potent survival factor for human prostate cancer cells. These cells constitutively produce 5-HETE in serum-free medium with no added stimulus. Exogenous arachidonate markedly increases the production of 5-HETE. Inhibition of 5-lipoxygenase by MK886 completely blocks 5-HETE production and induces massive apoptosis in both hormone-responsive (LNCaP) and -nonresponsive (PC3) human prostate cancer cells. This cell death is very rapid: cells treated with MK886 showed mitochondrial permeability transition between 30 and 60 min, externalization of phosphatidylserine within 2 hr, and degradation of DNA to nucleosomal subunits beginning within 2–4 hr posttreatment. Cell death was effectively blocked by the thiol antioxidant, N-acetyl-l-cysteine, but not by androgen, a powerful survival factor for prostate cancer cells. Apoptosis was specific for 5-lipoxygenase—programmed cell death was not observed with inhibitors of 12-lipoxygenase, cyclooxygenase, or cytochrome P450 pathways of arachidonic acid metabolism. Exogenous 5-HETE protects these cells from apoptosis induced by 5-lipoxygenase inhibitors, confirming a critical role of 5-lipoxygenase activity in the survival of these cells. These findings provide a possible molecular mechanism by which dietary fat may influence the progression of prostate cancer. PMID:9789062

  20. Arachidonic acid can function as a signaling modulator by activating the TRPM5 cation channel in taste receptor cells.

    PubMed

    Oike, Hideaki; Wakamori, Minoru; Mori, Yasuo; Nakanishi, Hiroki; Taguchi, Ryo; Misaka, Takumi; Matsumoto, Ichiro; Abe, Keiko

    2006-09-01

    Vertebrate sensory cells such as vomeronasal neurons and Drosophila photoreceptor cells use TRP channels to respond to exogenous stimuli. In mammalian taste cells, bitter and sweet substances as well as some amino acids are received by G protein-coupled receptors (T2Rs or T1Rs). As a result of activation of G protein and phospholipase Cbeta2, the TRPM5 channel is activated. Intracellular Ca(2+) is known to be a TRPM5 activator, but the participation of lipid activators remains unreported. To clarify the effect of arachidonic acid on TRPM5 in taste cells, we investigated the expression profile of a series of enzymes involved in controlling the intracellular free arachidonic acid level, with the result that in a subset of taste bud cells, monoglyceride lipase (MGL) and cyclooxygenase-2 (COX-2) are expressed as well as the previously reported group IIA phospholipase A(2) (PLA(2)-IIA). Double-labeling analysis revealed that MGL, COX-2 and PLA(2)-IIA are co-expressed in some cells that express TRPM5. We then investigated whether arachidonic acid activates TRPM5 via a heterologous expression system in HEK293 cells, and found that its activation occurred at 10 microM arachidonic acid. These results strongly suggest the possibility that arachidonic acid acts as a modulator of TRPM5 in taste signaling pathways. PMID:16935556

  1. Protein kinase C is involved in stimulation of arachidonic acid metabolism in Madin-Darby canine kidney (MDCK) cells

    SciTech Connect

    Parker, J.; Daniel, L.W.; Waite, M.

    1986-05-01

    The authors used 12-O-tetradecanoyl-phorbol-13-acetate (TPA) to directly stimulate protein kinase C (PKC) in order to examine the role of PKC in transduction of biological signals that increase metabolism of arachidonic acid. Release of radioactive arachidonic acid and prostaglandins from TPA-stimulated MDCK cells is inhibited by either of two PKC inhibitors: 1-(5-isoquinolinesulfonyl)piperazine and 1-octadecyl-2-methoxy-glycero-3-phosphocholine (ALP). ALP is unable to inhibit cyclooxygenase when added into an in vitro assay for this enzyme. Furthermore, TPA induces de novo synthesis of cyclooxygenase in MDCK cells but ALP fails to prevent this effect of TPA. Thus, cyclooxygenase activity appears to be independent of PKC and TPA can still induce de novo synthesis of cyclooxygenase even in the presence of the PKC inhibitor ALP. Also, ALP has no effect on the release of arachidonic acid which occurs upon addition of the calcium ionophore A23187 to MDCK cells suggesting that there are multiple mechanisms to mobilize arachidonic acid. Their data indicate that activation of PKC by TPA leads to increased release of arachidonic acid through regulation of phospholipase(s) by PKC.

  2. 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

  3. 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

  4. The inner ear and the neurologist

    PubMed Central

    Agrup, Charlotte; Gleeson, Michael; Rudge, Peter

    2007-01-01

    Inner ear disorders are common and patients with vestibular failure often present to a neurology clinic because of their dizziness, gait unsteadiness and oscillopsia. Vestibular disorders can be divided into peripheral and central vestibular disorders. Most of the peripheral vestibular disorders have a clinical diagnosis, and a thorough history and examination will often provide a clear direction as to the diagnosis. Correct diagnosis allows treatment for many of the peripheral and central vestibular disorders. As inner ear damage is generally irreversible, early diagnosis allowing prompt treatment is important. The aim of this review is to discuss some audiovestibular conditions that may well appear in a neurology clinic, and to discuss some recent advances within the audiovestibular field that may be of interest to neurologists. Some of the most common audiovestibular conditions will be discussed along side more uncommon conditions. PMID:17229743

  5. Ear replantation after human bite avulsion injury.

    PubMed

    Horta, Ricardo; Costa-Ferreira, António; Costa, Joana; Silva, Pedro; Amarante, José Manuel; Silva, Alvaro; Filipe, Rita

    2011-07-01

    Traumatic auricular amputation due to human bite is not a common event, but it constitutes a difficult challenge for the reconstructive surgeon. Microsurgery can be performed in some cases, but replantation of a severed ear without microsurgery can be a safe alternative. We present a case of a 44-year-old male individual who was involved in a fight and sustained a human bite, resulting in almost a complete amputation of his right ear. The Baudet technique has been used successfully. It is a simple technique and very reliable because it allows a great surface of contact between the graft and the vascular bed, substantially increasing its odds of survival in cases presenting with high risk of infection such as human bite injury. It also produces excellent aesthetic results. PMID:21772155

  6. 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

  7. Ringing ears: the neuroscience of tinnitus.

    PubMed

    Roberts, Larry E; Eggermont, Jos J; Caspary, Donald M; Shore, Susan E; Melcher, Jennifer R; Kaltenbach, James A

    2010-11-10

    Tinnitus is a phantom sound (ringing of the ears) that affects quality of life for millions around the world and is associated in most cases with hearing impairment. This symposium will consider evidence that deafferentation of tonotopically organized central auditory structures leads to increased neuron spontaneous firing rates and neural synchrony in the hearing loss region. This region covers the frequency spectrum of tinnitus sounds, which are optimally suppressed following exposure to band-limited noise covering the same frequencies. Cross-modal compensations in subcortical structures may contribute to tinnitus and its modulation by jaw-clenching and eye movements. Yet many older individuals with impaired hearing do not have tinnitus, possibly because age-related changes in inhibitory circuits are better preserved. A brain network involving limbic and other nonauditory regions is active in tinnitus and may be driven when spectrotemporal information conveyed by the damaged ear does not match that predicted by central auditory processing. PMID:21068300

  8. Synthesis of site-specifically labeled arachidonic acids as mechanistic probes for prostaglandin H synthase.

    PubMed

    Peng, Sheng; McGinley, Chris M; van der Donk, Wilfred A

    2004-02-01

    [structure: see text] Prostaglandin H synthase catalyzes the first committed step in the biosynthesis of prostaglandins and thromboxane. Herein we report the synthesis of four site-specifically labeled arachidonic acids for investigation of the radical intermediate formed during this enzymatic reaction. Two compounds were prepared using a common C9-C11 fragment, while another target was synthesized using a previously reported advanced intermediate. An alkyne coupling followed by hydrogenation and Wittig reaction was used to prepare the final labeled substrate. PMID:14748590

  9. 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

  10. COX-2-dependent and -independent biosynthesis of dihydroxy-arachidonic acids in activated human leukocytes

    PubMed Central

    Tejera, Noemi; Boeglin, William E.; Suzuki, Takashi; Schneider, Claus

    2012-01-01

    Biosynthesis of 5,15-dihydroxyeicosatetraenoic acid (5,15-diHETE) in leukocytes involves consecutive oxygenation of arachidonic acid by 5-lipoxygenase (LOX) and 15-LOX in either order. Here, we analyzed the contribution of cyclooxygenase (COX)-2 to the biosynthesis of 5,15-diHETE and 5,11-diHETE in isolated human leukocytes activated with lipopolysaccharide and calcium ionophore A23187. Transformation of arachidonic acid was initiated by 5-LOX providing 5S-HETE as a substrate for COX-2 forming 5S,15S-diHETE, 5S,15R-diHETE, and 5S,11R-diHETE as shown by LC/MS and chiral phase HPLC analyses. The levels of 5,15-diHETE were 0.45 ± 0.2 ng/106 cells (mean ± SEM, n = 6), reaching about half the level of LTB4 (1.3 ± 0.5 ng/106 cells, n = 6). The COX-2 specific inhibitor NS-398 reduced the levels of 5,15-diHETE to below 0.02 ng/106 cells in four of six samples. Similar reduction was achieved by MK-886, an inhibitor of 5-LOX activating protein but the above differences were not statistically significant. Aspirin treatment of the activated cells allowed formation of 5,15-diHETE (0.1 ± 0.05 ng/106 cells, n = 6) but, as expected, abolished formation of 5,11-diHETE. The mixture of activated cells also produced 5S,12S-diHETE with the unusual 6E,8Z,10E double bond configuration, implicating biosynthesis by 5-LOX and 12-LOX activity rather than by hydrolysis of the leukotriene A4-epoxide. Exogenous octadeuterated 5S-HETE and 15S-HETE were converted to 5,15-diHETE, implicating that multiple oxygenation pathways of arachidonic acid occur in activated leukocytes. The contribution of COX-2 to the biosynthesis of dihydroxylated derivatives of arachidonic acid provides evidence for functional coupling with 5-LOX in activated human leukocytes. PMID:22068350

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

    NASA Astrophysics Data System (ADS)

    Kratzsch, S.; Drössler, 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.

  12. Arachidonic Acid and Other Fatty Acids Directly Activate Potassium Channels in Smooth Muscle Cells

    NASA Astrophysics Data System (ADS)

    Ordway, Richard W.; Walsh, John V.; Singer, Joshua J.

    1989-06-01

    Arachidonic acid, as well as fatty acids that are not substrates for cyclooxygenase and lipoxygenase enzymes, activated a specific type of potassium channel in freshly dissociated smooth muscle cells. Activation occurred in excised membrane patches in the absence of calcium and all nucleotides. Therefore signal transduction pathways that require such soluble factors, including the NADPH-dependent cytochrome P450 pathway, do not mediate the response. Thus, fatty acids directly activate potassium channels and so may constitute a class of signal molecules that regulate ion channels.

  13. 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

  14. 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

  15. 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.

  16. 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

  17. Do Swiftlets have an ear for echolocation? The functional morphology of Swiftlets' middle ears.

    PubMed

    Thomassen, Henri A; Gea, Stefan; Maas, Steve; Bout, Ron G; Dirckx, Joris J J; Decraemer, Willem F; Povel, G David E

    2007-03-01

    The Oilbird and many Swiftlet species are unique among birds for their ability to echolocate. Echolocaters may benefit from improved hearing sensitivity. Therefore, morphological adaptations to echolocation might be present in echolocating birds' middle ears. We studied the functional morphology of the tympano-ossicular chain of seven specimens of four echolocating Swiftlet species and one specimen each of five non-echolocating species. Three dimensional (3D) reconstructions were made from micro-Computer-Tomographic (muCT) scans. The reconstructions were used in functional morphological analyses and model calculations. A two dimensional (2D) rigid rod model with fixed rotational axes was developed to study footplate output-amplitudes and to describe how changes in the arrangement of the tympano-ossicular chain affect its function. A 3D finite element model was used to predict ossicular-chain movement and to investigate the justification of the 2D approach. No morphological adaptations towards echolocation were found in the middle-ear lever system or in the mass impedance of the middle ear. A wide range of middle-ear configurations result in maximum output-amplitudes and all investigated species are congruent with these predicted best configurations. Echolocation is unlikely to depend on adaptations in the middle ear tympano-ossicular chain. PMID:17229537

  18. Antioxidant properties of methanolic extracts from several ear mushrooms.

    PubMed

    Mau, J L; Chao, G R; Wu, K T

    2001-11-01

    Five kinds of ear mushrooms are commercially available in Taiwan, including black, red, jin, snow, and silver ears. Methanolic extracts were prepared from these ear mushrooms, and their antioxidant properties were studied. For all methanolic extracts from ear mushrooms, the antioxidant activities in the 1,3-diethyl-2-thiobarbituric acid method were moderate (38.6 approximately 74.6%) at 1.0-5.0 mg/mL. Methanolic extracts from red, jin, and snow ears showed excellent antioxidant activities in the conjugated diene method at 5.0 mg/mL. At 5.0 mg/mL, reducing powers of methanolic extracts were in the descending order of snow > black approximately red approximately jin > silver ears. The scavenging effect of methanolic extracts from ear mushrooms on 1,1-diphenyl-2-picrylhydrazyl radicals was excellent except for that from silver ears. Ear mushroom extracts were not good scavengers for hydroxyl free radicals but were good chelators for ferrous ions. Naturally occurring antioxidants, including ascorbic acid, tocopherols, and total phenols, were found in the methanolic extracts. However, beta-carotene was not detected. Total antioxidant components were 15.69, 30.09, 27.83, 49.17, and 31.70 mg/g for black, red, jin, snow, and silver ears, respectively. PMID:11714344

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. Arachidonate metabolism increases as rat alveolar type II cells differentiate in vitro

    SciTech Connect

    Lipchik, R.J.; Chauncey, J.B.; Paine, R.; Simon, R.H.; Peters-Golden, M. )

    1990-08-01

    Rat type II alveolar epithelial cells are known to undergo morphological and functional changes when maintained in culture for several days. Having previously demonstrated that these cells can deacylate free arachidonic acid (AA) and metabolize it to products of the cyclooxygenase pathway, the present study was undertaken to determine whether in vitro differentiation was accompanied by alterations in the availability and metabolism of AA. We assessed the constitutive and ionophore A23187-induced deacylation and metabolism of endogenous AA, as well as the metabolism of exogenously supplied AA, in primary cultures of rat type II cells at days 2, 4, and 7 after isolation. Levels of free endogenous AA were increased at day 4, whereas eicosanoid synthesis, predominantly prostaglandin E2 and prostacyclin, increased markedly only at day 7. A similar time course of augmentation of prostanoid release was seen in response to exogenous AA. Type II cells cultured on fibronectin, intended to hasten cell flattening and spreading, demonstrated accelerated increases in available free AA in response to A23187; cells cultured on basement membrane derived from Engelbreth-Holm-Swarm mouse sarcoma, known to maintain the type II phenotype, exhibited diminished levels of available free AA. From these findings, we conclude that alterations in arachidonate metabolism are linked to alterations in cellular phenotype. The potentiation of eicosanoid synthesis accompanying in vitro differentiation suggests a possible role for the alveolar epithelium in the modulation of inflammation and fibrosis in the distal lung.

  6. 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.

  7. 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.

  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. 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

  10. 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

  11. 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

  12. Chinchilla middle-ear admittance and sound power: High-frequency estimates and effects of inner-ear modifications

    PubMed Central

    Ravicz, Michael E.; Rosowski, John J.

    2012-01-01

    The middle-ear input admittance relates sound power into the middle ear (ME) and sound pressure at the tympanic membrane (TM). ME input admittance was measured in the chinchilla ear canal as part of a larger study of sound power transmission through the ME into the inner ear. The middle ear was open, and the inner ear was intact or modified with small sensors inserted into the vestibule near the cochlear base. A simple model of the chinchilla ear canal, based on ear canal sound pressure measurements at two points along the canal and an assumption of plane-wave propagation, enables reliable estimates of YTM, the ME input admittance at the TM, from the admittance measured relatively far from the TM. YTM appears valid at frequencies as high as 17 kHz, a much higher frequency than previously reported. The real part of YTM decreases with frequency above 2 kHz. Effects of the inner-ear sensors (necessary for inner ear power computation) were small and generally limited to frequencies below 3 kHz. Computed power reflectance was ∼0.1 below 3.5 kHz, lower than with an intact ME below 2.5 kHz, and nearly 1 above 16 kHz. PMID:23039439

  13. 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

  14. 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

  15. Properties of acid-induced currents in mouse dorsal root ganglia neurons.

    PubMed

    Ergonul, Zuhal; Yang, Lei; Palmer, Lawrence G

    2016-05-01

    Acid-sensing ion channels (ASICs) are cation channels that are activated by protons (H(+)). They are expressed in neurons throughout the nervous system and may play important roles in several neurologic disorders including inflammation, cerebral ischemia, seizures, neurodegeneration, anxiety, depression, and migraine. ASICs generally produce transient currents that desensitize in response to a decrease in extracellular pH Under certain conditions, the inactivation of ASICs can be incomplete and allow them to produce sustained currents. Here, we characterize the properties of both transient and sustained acid-induced currents in cultured mouse dorsal root ganglia (DRG) neurons. At pH levels between 7.3 and 7.1 they include "window currents" through ASICs. With stronger acid signals sustained currents are maintained in the absence of extracellular Na(+) or the presence of the ASIC blockers amiloride and Psalmotoxin-1(PcTx1). These sustained responses may have several different origins in these cells, including acid-induced stimulation of inward Cl(-) currents, block of outward K(+) currents, and augmentation of inward H(+) currents, properties that distinguish these novel sustained currents from the well-characterized transient currents. PMID:27173673

  16. 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

  17. 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

  18. Salicylic acid induces mitochondrial injury by inhibiting ferrochelatase heme biosynthesis activity.

    PubMed

    Gupta, Vipul; Liu, Shujie; Ando, Hideki; Ishii, Ryohei; Tateno, Shumpei; Kaneko, Yuki; Yugami, Masato; Sakamoto, Satoshi; Yamaguchi, Yuki; Nureki, Osamu; Handa, Hiroshi

    2013-12-01

    Salicylic acid is a classic nonsteroidal anti-inflammatory drug. Although salicylic acid also induces mitochondrial injury, the mechanism of its antimitochondrial activity is not well understood. In this study, by using a one-step affinity purification scheme with salicylic acid-immobilized beads, ferrochelatase (FECH), a homodimeric enzyme involved in heme biosynthesis in mitochondria, was identified as a new molecular target of salicylic acid. Moreover, the cocrystal structure of the FECH-salicylic acid complex was determined. Structural and biochemical studies showed that salicylic acid binds to the dimer interface of FECH in two possible orientations and inhibits its enzymatic activity. Mutational analysis confirmed that Trp301 and Leu311, hydrophobic amino acid residues located at the dimer interface, are directly involved in salicylic acid binding. On a gel filtration column, salicylic acid caused a shift in the elution profile of FECH, indicating that its conformational change is induced by salicylic acid binding. In cultured human cells, salicylic acid treatment or FECH knockdown inhibited heme synthesis, whereas salicylic acid did not exert its inhibitory effect in FECH knockdown cells. Concordantly, salicylic acid treatment or FECH knockdown inhibited heme synthesis in zebrafish embryos. Strikingly, the salicylic acid-induced effect in zebrafish was partially rescued by FECH overexpression. Taken together, these findings illustrate that FECH is responsible for salicylic acid-induced inhibition of heme synthesis, which may contribute to its antimitochondrial and anti-inflammatory function. This study establishes a novel aspect of the complex pharmacological effects of salicylic acid. PMID:24043703

  19. The timing of acid-induced increase in saliva secretion in transplanted submandibular glands.

    PubMed

    Liu, X J; Li, M; Su, J Z; Xie, Z; Yu, G Y

    2015-08-01

    The purpose of this study was to determine the timing of acid-induced increase in saliva secretion and to investigate the possibility of parasympathetic reinnervation of transplanted submandibular glands (SMGs). Citric acid stimulation-induced changes in secretion of transplanted SMGs were evaluated in 27 patients who underwent SMG transplantation for keratoconjunctivitis sicca (KCS); (99m)Tc scintigraphy and Schirmer tests were done at 1, 3, 6, and 9 months after transplantation. Acetylcholinesterase staining was conducted to confirm the presence of parasympathetic reinnervation in three SMGs at 6 and 9 months after transplantation. Schirmer tests showed significantly increased secretion of the transplanted SMGs after acid stimulation at 6 and 9 months, but not at 1 and 3 months. On (99m)Tc scintigraphy, no decline was detected on the dynamic time-activity curve after acid stimulation at 1 and 3 months, but a decline was detected in nine glands at 6 months and in 19 glands at 9 months. No decline was observed in the remaining eight glands at 9 months after transplantation. The histology findings were consistent with scintigraphy results. In conclusion, acid-induced increase in saliva secretion occurs at ≥6 months after SMG transplantation, and parasympathetic reinnervation of the transplanted SMG might occur. PMID:25697065

  20. 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

  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. EARS, MARS combined radio observations - 2014

    NASA Astrophysics Data System (ADS)

    Tomezzoli, Giancarlo

    2014-02-01

    The Lyrid meteor shower was generated on 21-22 April 2014 by the passage of the Earth through the path of the debris of the comet C/1861 G1 (Thatcher). The Camelopardalids meteor shower was generated on 23-24 May 2014 by the passage of the Earth through the path of the debris of the comet 209P/Linear. The EurAstro Radio Station (EARS) and the Malta Astro Radio Station (MARS) were operated in parallel for two combined radio observation campaigns. The campaigns revealed that further combined radio observation campaigns are necessary to solve the problem of estimating the number of lost radio meteor echoes.

  3. 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. PMID:26903746

  4. 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

  5. Fly-ear inspired acoustic sensors for gunshot localization

    NASA Astrophysics Data System (ADS)

    Liu, Haijun; Currano, Luke; Gee, Danny; Yang, Benjamin; Yu, Miao

    2009-05-01

    The supersensitive ears of the parasitoid fly Ormia ochracea have inspired researchers to develop bio-inspired directional microphone for sound localization. Although the fly ear is optimized for localizing the narrow-band calling song of crickets at 5 kHz, experiments and simulation have shown that it can amplify directional cues for a wide frequency range. In this article, a theoretical investigation is presented to study the use of fly-ear inspired directional microphones for gunshot localization. Using an equivalent 2-DOF model of the fly ear, the time responses of the fly ear structure to a typical shock wave are obtained and the associated time delay is estimated by using cross-correlation. Both near-field and far-field scenarios are considered. The simulation shows that the fly ear can greatly amplify the time delay by ~20 times, which indicates that with an interaural distance of only 1.2 mm the fly ear is able to generate a time delay comparable to that obtained by a conventional microphone pair with a separation as large as 24 mm. Since the parameters of the fly ear structure can also be tuned for muzzle blast and other impulse stimulus, fly-ear inspired acoustic sensors offers great potential for developing portable gunshot localization systems.

  6. 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.

  7. Effect of the middle ear reflex on sound transmission to the inner ear of rat.

    PubMed

    Pilz, P K; Ostwald, J; Kreiter, A; Schnitzler, H U

    1997-03-01

    The effect of the acoustic middle ear reflex (MER) was quantified using electrodes chronically implanted in the middle ears of rats. Cochlear microphonics (CM) and middle ear muscle EMG were measured under light Ketamin anesthesia after stimulation with tone pulses of 5-20 kHz ranging between 75 and 120 dB SPL. With increasing intensity, the CM measured before the onset of the MER increased to a maximum amplitude and then decreased with higher SPLs. At 10 kHz this maximum was reached at 95 dB SPL, for other stimulus frequencies at higher SPLs. After a latency of 10-20 ms, CM to 10 kHz stimuli of 80-95 dB SPL were decreased by the attenuating action of the MER. The lowest threshold of the MER was also measured at 10 kHz (77 dB SPL in the mean). To stimuli greater than 100 dB SPL after a latency of 6-10 ms, the CM amplitude was increased. That this CM increase to intense stimuli is caused by the action of the MER was confirmed by control experiments such as cutting the tendons of the middle ear muscles. The CM decrease to stimuli below 100 dB SPL, as well as the increase to very intense stimuli, can be explained by sound attenuation caused by the MER, together with the nonlinear dependence of CM amplitude on stimulus level. The observed shift of the maxima of the CM input-output function by the MER to higher stimulus levels probably indicates an increase of the dynamic range of the ear. PMID:9083814

  8. 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/.

  9. Involvement of Nitric Oxide on Calcium Mobilization and Arachidonic Acid Pathway Activation during Platelet Aggregation with different aggregating agonists

    PubMed Central

    Banerjee, Debipriya; Mazumder, Sahana; Kumar Sinha, Asru

    2016-01-01

    Platelet aggregation by different aggregating agonists is essential in the normal blood coagulation process, the excess of which caused acute coronary syndrome (ACS). In all cases, the activation of arachidonic acid by cycloxygenase was needed for the synthesis of thromboxane A2 (TXA2) but the mechanism of arachidonic acid release in platelets remains obscure. Studies were conducted to determine the role of nitric oxide (NO), if any, on the release of arachidonic acid in platelets. The cytosolic Ca2+ was visualized and quantitated by fluorescent spectroscopy by using QUIN-2. NO was measured by methemoglobin method. Arachidonic acid was determined by HPLC. TXA2 was measured as ThromboxaneB2 (TXB2) by ELISA. Treatment of platelets in platelet-rich plasma (PRP) with different aggregating agents resulted in the inhibition of nitric oxide synthase (NOS) which inhibited the production of NO synthesis and increased TXA2 synthesis. Furthermore, the treatment of washed PRP with different platelet aggregating agents resulted in the increase of [Ca2+] in nM ranges. In contrast, the pre-treatment of washed PRP with aspirin increased platelet NO level and inhibited the Ca2+ mobilization and TXA2 synthesis. These results indicated that the aggregation of platelets by different aggregating agonists was caused by the cytosolic Ca2+ mobilization due to the inhibition of NOS.

  10. 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.

  11. On the ability of prostaglandin E1, and arachidonic acid to modulate experimentally induced oedema in the rat paw.

    PubMed Central

    Lewis, A J; Nelson, D J; Sugrue, M F

    1975-01-01

    1 Prostaglandins E1 and E2 but not prostaglandin F2alpha, arachidonic acid or linolenic acid, produced slight oedema when injected into the rat hindpaw. 2 Prostaglandin E1 potentiated hindpaw oedema produced by carrageenan, kaolin, bradykinin and trypsin but not that produced by 5-hydroxytryptamine (5-HT), histamine, dextran B or compound 48/80. Carrageenan- and bradykinin-induced paw oedemas were also potentiated by prostaglandin E2. Arachidonic acid potentiated responses to carrageenan and kaolin but not responses to bradykinin, trypsin, 5-HT, histamine, dextran B or compound 48/80. Linolenic acid did not potentiate hindpaw oedema induced by carrageenan. 3 Potentiation of carrageenan-induced oedema by prostaglandin E1 was not diminished by pretreatment with indomethacin, hydrocortisone or cyproheptadine. However, arachidonic acid potentiation of carrageenan oedema was reduced by pretreatment with non-steroidal anti-inflammatory drugs but not by anti-inflammatory steroids or by paracetamol. 4 The enhancement of the response to carrageenan and kaolin by prostaglandins E1, E2 and arachidonic acid is discussed in terms of kinin mediation. PMID:1182349

  12. 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 ...

  13. 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...

  14. 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.

  15. 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

  16. Evaluation of fungal flora in normal and diseased canine ears.

    PubMed

    Campbell, Jacquelyn J; Coyner, Kimberly S; Rankin, Shelley C; Lewis, Thomas P; Schick, Anthea E; Shumaker, Amy K

    2010-12-01

    This study was undertaken to characterize otic fungal flora encountered in normal dogs, atopic dogs with no clinical or cytological evidence of otitis and dogs with otitis externa. Forty-two normal dogs, 23 atopic dogs and 32 dogs with otitis were included in the study. Samples for otic fungal culture and cytology were obtained from all animals, for a total of 194 ears. Sixty-seven ear samples (34%) were culture positive for saprophytic fungal organisms, as follows: 43 (64%) Penicillium species, 13 (19%) Aspergillus species and the remaining 17% comprised of various other saprophytic fungal organisms. Cytological evidence of saprophytic fungal colonization or infection was not found in any animal. There was no relationship between positive saprophytic fungal culture and any study group. Thirty-three ear samples (17%) were positive for Malassezia pachydermatis. Cytological findings of Malassezia were significantly associated with positive culture for Malassezia (P = 0.006 left ear; P = 0.019 right ear). Furthermore, increased numbers of Malassezia led to a higher chance of positive culture (P = 0.003 left ear; P = 0.008 right ear; McNemar's test). Malassezia pachydermatis was more likely to be cultured from ears with increased cerumen. Ear type (erect or pendulous) was not significantly associated with positive culture for Malassezia or saprophytic fungal organisms. There was no relationship between positive Malassezia culture and any study group; however, Malassezia was more likely to be cultured from individual dogs in the atopic or otitis groups that also had other dermatological signs consistent with allergic dermatitis and/or pyoderma (P = 0.031 left ear; P = 0.005 right ear). PMID:20868397

  17. 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.

  18. Arachidonic acid stimulates formation of a novel complex containing nucleolin and RhoA.

    PubMed

    Garcia, Melissa C; Williams, Jason; Johnson, Katina; Olden, Kenneth; Roberts, John D

    2011-02-18

    Arachidonic acid (AA) stimulates cell adhesion through a p38 mitogen activated protein kinase-mediated RhoA signaling pathway. Here we report that a proteomic screen following AA-treatment identified nucleolin, a multifunctional nucleolar protein, in a complex with the GTPase, RhoA, that also included the Rho kinase, ROCK. AA-stimulated cell adhesion was inhibited by expression of nucleolin-targeted shRNA and formation of the multiprotein complex was blocked by expression of dominant-negative RhoA. AA-treatment also induced ROCK-dependent serine phosphorylation of nucleolin and translocation of nucleolin from the nucleus to the cytoplasm, where it appeared to co-localize with RhoA. These data suggest the existence of a new signaling pathway through which the location and post-translational state of nucleolin are modulated. PMID:21281639

  19. 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

  20. 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

  1. 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.

  2. 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

  3. 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

  4. Tumor cell-derived 12(S)-hydroxyeicosatetraenoic acid induces microvascular endothelial cell retraction.

    PubMed

    Honn, K V; Tang, D G; Grossi, I; Duniec, Z M; Timar, J; Renaud, C; Leithauser, M; Blair, I; Johnson, C R; Diglio, C A

    1994-01-15

    Our previous work demonstrated that the 12-lipoxygenase metabolite of arachidonic acid, 12(S)-hydroxyeicosatetraenoic acid [12(S)-HETE] induced a nondestructive and reversible retraction of cultured endothelial cells. In the current study we tested the hypothesis that tumor cells produce 12(S)-HETE during their interactions with endothelial cells which in turn induces endothelial cell retraction. Coincubation of Lewis lung carcinoma cells or elutriated B16 amelanotic melanoma (B16a) cells but not 3T3 fibroblasts with microvascular endothelial cells (CD3) resulted in a time- and concentration-dependent retraction of the CD3 monolayers as revealed by quantitative binding assays and phase contrast microscopy. Lewis lung carcinoma cell-induced endothelial cell retraction was blocked by specific lipoxygenase inhibitors but not by cyclooxygenase inhibitors, suggesting the involvement of a lipoxygenase metabolite(s). Radioimmunoassay and high-performance liquid chromatography analysis of tumor cell extracts identified 12(S)-HETE as the major lipoxygenase metabolite of arachidonic acid and tumor cell generation of 12(S)-HETE was specifically blocked by a select 12-lipoxygenase inhibitor N-benzyl-N-hydroxy-5-phenyl-pentamide. The identity and stereochemistry of tumor cell-derived 12-HETE was substantiated by gas chromatography-mass spectrometry analysis and chiral phase high-performance liquid chromatography, respectively. Lewis lung carcinoma cell adhesion to CD3 monolayers was accompanied by an enhanced 12(S)-HETE biosynthesis by tumor cells, which paralleled the tumor cell-induced endothelial cell retraction in a cell number-dependent manner. Pretreatment of tumor cells with N-benzyl-N-hydroxy-5-phenylpentamide inhibited both increased 12(S)-HETE biosynthesis and tumor cell-induced endothelial cell retraction. Highly metastatic variants of elutriated B16a cells which had been shown to produce large quantities of 12(S)-HETE induced significant CD3 cell retraction, while low metastatic subpopulations of B16a cells which synthesized no or little 12(S)-HETE did not induce endothelial cell retraction. These results suggest that 12(S)-HETE synthesis during tumor cell-endothelial cell interactions may represent a key contributory factor in cancer metastasis. PMID:8275495

  5. 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)

  6. [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

  7. 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

  8. 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…

  9. 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...

  10. 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...

  11. 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...

  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, 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...

  14. 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

  15. 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.

  16. 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. PMID:27022627

  17. 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

  18. 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 14-3-3β and 14-3-3ε, were down-regulated in response to betulinic acid treatment, which is consistent with the decrease in expression of the target genes 14-3-3β and 14-3-3ε. 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

  19. Endothelial connexin43 mediates acid-induced increases in pulmonary microvascular permeability.

    PubMed

    Parthasarathi, Kaushik

    2012-07-01

    Acid aspiration, a common cause of acute lung injury, leads to alveolar edema. Increase in lung vascular permeability underlies this pathology. To define mechanisms, isolated rat lungs were perfused with autologous blood. Hydrochloric acid and rhodamine-dextran 70 kDa (RDx70) were coinstilled into an alveolus by micropuncture. RDx70 fluorescence was used to establish the spatial distribution of acid. Subsequently, FITC-dextran 20 kDa (FDx20) was infused into microvessels for 60 min followed by a 10-min HEPES-buffered saline wash. During the infusion, FITC fluorescence changes were recorded to quantify the ratio of peak to postwash fluorescence. The ratio, termed normalized fluorescence, was low for acid compared with buffer instillation both in microvessels abutting acid-treated alveoli and those located more than 700 μm away. In contrast, the normalized fluorescence was similar to buffer controls when a higher molecular weight tracer (FITC-dextran 70 kDa) was infused instead of FDx20, suggesting that normalized FDx20 fluorescence faithfully represented microvascular permeability. Inhibiting endothelial connexin43 (Cx43) gap junction communication with Gap27 blunted the acid-induced reduction in normalized fluorescence, although scrambled Gap27 did not have any effect. The blunting was evident not only in microvessels away from the site of injury, but also in those abutting directly injured alveoli. Thus the new fluorescence-based method reveals that acid increases microvascular permeability both at acid-instilled and away sites. Inhibiting endothelial Cx43 blocked the permeability increase even at the direct injury sites. These data indicate for the first time that Cx43-dependent mechanisms mediate acid-induced increases in microvascular permeability. Cx43 may be a therapeutic target in acid injury. PMID:22561459

  20. Microvascular salvage of a thrombosed total ear replant.

    PubMed

    Senchenkov, Alex; Jacobson, Steven R

    2013-07-01

    Microvascular replantation, when possible, is the treatment of choice for total ear amputations. Both arterial and venous reconstruction should be attempted. The present case report describes a successful total ear replantation in a 45-year-old woman whose ear was amputated due to a horse accident. Venous thrombosis subsequently occurred and was managed with anticoagulation and leech therapy. Eighty hours after the replantation, arterial thrombosis took place. The posterior auricular artery thrombosed anastomosis was resected and reconstructed with an interposition vein graft. This report illustrates the feasibility of the successful microvascular salvage of a thrombosed total ear replant. It suggests the need for close clinical monitoring of the replanted ear and prompt microvascular reexploration in an event of the loss of arterial flow. PMID:23640855

  1. [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

  2. 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

  3. The comparative anatomy of the pig middle ear cavity: a model for middle ear inflammation in the human?

    PubMed Central

    PRACY, J. P.; WHITE, A.; MUSTAFA, Y.; SMITH, D.; PERRY, M. E.

    1998-01-01

    This study was undertaken to develop a functional model of otitis media with effusion (OME) in the pig (Sus scrofa), with the purpose of investigating the origin of lymphocytes populating the middle ear during the course of an inflammatory process. The relevance of the model to the human condition of OME is to a large extent dependent on the anatomical and physiological similarities between the middle ear cavity and the pharyngeal lymphoid tissue of the pig and man. Anatomical specimens were collected from 7 young Large White pigs to determine the gross anatomy of the middle ear cavity and the histological characteristics of the middle ear mucosa. It was found that the anatomy of the 3 parts of the middle ear cavity in man and in the pig is broadly similar, although some minor differences were observed. The porcine eustachian tube was seen to be cartilaginous throughout its length in contrast to the part osseous, part cartilaginous structure found in man; the porcine ossicles were slightly different in shape to those of man and the air cell system was situated inferior to the tympanic cavity in the pig as opposed to posteriorly in man. This paper describes the structure and morphology of the pig middle ear cavity and compares and contrasts it with that of man. The minor differences observed are of anatomical importance but do not diminish the usefulness of the pig middle ear cleft as a potential model for human middle ear disorders. PMID:9688502

  4. "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…

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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...

  10. 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...

  11. 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 21 week 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 Reissner’s 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

  12. 3D Ear Identification Based on Sparse Representation

    PubMed Central

    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

  13. 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

  14. 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.

  15. 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

  16. 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

  17. [Hernia of the external ear canal of uncommon origin].

    PubMed

    Llorente Arenas, E M; Fraile Rodrigo, J; Naya Gálvez, M J; Marín Garrido, C; Carmen Sampériz, L; Martínez Berganza, R; Damborenea Tajada, J

    2000-01-01

    The temporo-mandibular joint is directly related to the anterior wall of the external ear canal. Therefore, defects in this wall may lead to herniation of the soft tissues of the temporo-mandibular joint into the external ear canal. Such herniation usually is secondary to external injuries, iatrogenic trauma, neoplasms, and so on, but it may also be congenital. We report a well-documented case of temporo-mandibular joint herniation into the external ear canal of probable congenital origin. PMID:10799936

  18. 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

  19. [Introduction to the surgery of the middle ear: general principles].

    PubMed

    Babighian, G; Domínguez, 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

  20. 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

  1. 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.

  2. Effect of alpha Ni3S2 on arachidonic acid metabolites in cultured human lung cells (L132 cell line).

    PubMed

    Shirali, P; Teissier, E; Marez, T; Hildebrand, H F; Haguenoer, J M

    1994-04-01

    Our previous investigations have shown evidence of an interaction between alpha Ni3S2 and membranous and cellular lipids of lung cells with a significant increase in the linoleic, linolenic and arachidonic acid pool. The present work is designed to follow the metabolic fate of arachidonic acid in alpha Ni3S2-exposed human embryonic pulmonary epithelial cells (L132) in culture (50 microM alpha Ni3S2 for 3 days). The metabolites of arachidonic acid were assessed by HPLC determination coupled with UV or electrochemical detection. We determined malondialdehyde (MDA), hydroxyeicosatetraenoic acid (HETE), leukotrienes (LT) and reduced glutathione (GSH). In exposed cells we observed a significant increase of MDA, which is a breakdown product of lipid peroxidation. In addition, we noted significant increases of 5-HETE and 15-HETE in L132 cells resulting from the enzymatic reduction of 5-HPETE and 15-HPETE respectively. There was also a simultaneous decrease of GSH--confirmed by a strong decrease of GSH in exposed cells with respect to controls. 5-HPETE is furthermore converted to epoxides such as leukotriene A4 and we also quantified in exposed cells a significant increase of its subsequent catabolites LTB4, LTC4 and LTE4. These investigations show clearly that exposure of L132 cells to alpha Ni3S2 enhances lipid peroxidation based upon direct measurements of MDA and other metabolites of arachidonic acid. This lipid peroxidation is an autocatalytic free-radical process and could be responsible for DNA damage. PMID:8149492

  3. 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

  4. Unraveling lipid metabolism with microarrays: effects of arachidonate and docosahexaenoate acid on murine hepatic and hippocampal gene expression.

    PubMed

    Berger, Alvin; Mutch, David M; German, J Bruce; Roberts, Matthew-Alan

    2002-05-23

    The functions, actions, and regulation of polyunsaturated fatty acids (PUFAs) are beginning to be unraveled. Mice were fed diets rich in either arachidonic acid, docosahexaenoic acid, or both. Liver and hippocampus tissue were then analyzed through a combined gene expression-, lipid-, and behavioral- profiling strategy. Novel hippocampal PUFA-molecular targets suggest that PUFA transcriptionally regulated genes with roles in appetite and learning. PMID:12184799

  5. Partial purification from macrophages of a phospholipase A/sub 2/ that hydrolyzes arachidonic acid from phosphatidylcholine

    SciTech Connect

    Leslie, C.; Wall, M.; Zelarney, P.; Voelker, D.

    1987-05-01

    The first step in platelet-activating factor production and arachidonic acid release from stimulated inflammatory cells is thought to be the activation of a phospholipase A/sub 2/ (PLA/sub 2/). The mouse macrophage cell line, RAW 264, was found to contain PLA/sub 2/ activity that hydrolyzed /sup 3/H-arachidonic acid from sonicated dispersions of 1-0-alkyl-linked phosphatidylcholine (PC). The PLA/sub 2/ was cytosolic, required calcium, and exhibited a broad pH optimum between 6 and 10. When the hydrolysis of /sup 3/H-arachidonic acid from 1-palmitoyl- and 1-hexadecyl-linked PC (15 ..mu..M) was compared, slightly higher activity against 1-acyl-linked PC was found. However, the activity against 1-palmitoyl-linked PC substrates containing oleic or linoleic acids (sn-2) was considerably lower. To understand the properties of the PLA/sub 2/ in more detail, purification was undertaken. After ammonium sulfate precipitation the PLA/sub 2/ was fractionated over G150, on which it eluted slightly before an albumin marker. The enzyme bound to DEAE cellulose at pH 8.0 and was eluted in 0.3M NaCl. Further purification was achieved by hydrophobic chromatography over phenyl Sepharose followed by ion-exchange chromatography using Q-Sepharose resulting in 200-700-fold increases in specific activity. These results demonstrate the presence of a cytosolic PLA/sub 2/ in macrophages that shows specificity for arachidonic acid at the sn-2 position of PC, has an apparent molecular weight greater than or equal to albumin, is anionic at pH 8.0 and is relatively hydrophobic.

  6. 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.

  7. 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.

  8. Unraveling the Genetic Basis of Aspirin Hypersensitivity in Asthma Beyond Arachidonate Pathways

    PubMed Central

    Park, Se-Min; Park, Jong Sook; Park, Hae-Sim

    2013-01-01

    Although aspirin-exacerbated respiratory disease (AERD) has attracted a great deal of attention because of its association with severe asthma, it remains widely under-diagnosed in the asthmatic population. Oral aspirin challenge is the best method of diagnosing AERD, but this is a time-consuming procedure with serious complications in some cases. Thus, development of non-invasive methods for easy diagnosis is necessary to prevent unexpected complications of aspirin use in susceptible patients. For the past decade, many studies have attempted to elucidate the genetic variants responsible for risk of AERD. Several approaches have been applied in these genetic studies. To date, a limited number of biologically plausible candidate genes in the arachidonate and immune and inflammatory pathways have been studied. Recently, a genome-wide association study was performed. In this review, the results of these studies are summarized, and their limitations discussed. In addition to the genetic variants, changes in methylation patterns on CpG sites have recently been identified in a target tissue of aspirin hypersensitivity. Finally, perspectives on application of new genomic technologies are introduced; these will aid our understanding of the genetic pathogenesis of aspirin hypersensitivity in asthma. PMID:24003382

  9. On the safety of Mortierella alpina for the production of food ingredients, such as arachidonic acid.

    PubMed

    Streekstra, H

    1997-08-28

    Mortierella alpina is the most efficient production organism for arachidonic acid (AA) presently known. Since AA is being developed as a food ingredient, and since M. alpina has no history of use for such applications, we have undertaken this safety evaluation. M. alpina is a common soil fungus, to which humans are frequently exposed. The production strains are non-pathogenic and do not form potentially allergenic spores under production conditions. Moreover, there are no reliable reports in the literature connecting the species with disease or allergenic responses. No production of mycotoxins was observed, in line with the absence of literature reports describing such products, and with the results of toxicological tests. On solid growth media the strains showed antibiotic activity against Gram-positive bacteria. In submerged culture, which is used for AA production, no significant antibiotic activity was found. We conclude that M. alpina in general, and the AA production strains CBS 168.95 and CBS 169.95 in particular, should be considered safe for the submerged production of food ingredients. PMID:9304876

  10. 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

  11. 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

  12. 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

  13. Fluorescent HPLC assay for 20-HETE and other P-450 metabolites of arachidonic acid.

    PubMed

    Maier, K G; Henderson, L; Narayanan, J; Alonso-Galicia, M; Falck, J R; Roman, R J

    2000-08-01

    This study describes a fluorescent HPLC assay for measuring 20-hydroxyeicosatetraenoic acid (20-HETE) and other cytochrome P-450 metabolites of arachidonic acid in urine, tissue, and interstitial fluid. An internal standard, 20-hydroxyeicosa-6(Z),15(Z)-dienoic acid, was added to samples, and the lipids were extracted and labeled with 2-(2,3-naphthalimino)ethyl trifluoromethanesulfonate. P-450 metabolites were separated on a C18 reverse-phase HPLC column. Coelution and gas chromatography-mass spectrometry studies confirmed the identity of the 20-HETE peak. The 20-HETE peak can be separated from those for dihydroxyeicosatrienoic acids, other HETEs, and epoxyeicosatrienoic acids. Known amounts of 20-HETE were used to generate a standard curve (range 1-10 ng, r(2) = 0.98). Recovery of 20-HETE from urine averaged 95%, and the intra-assay variation was <5%. Levels of 20-HETE were measured in 100 microliter of urine and renal interstitial fluid or 0.1 mg of renal tissue. The assay was evaluated by studying the effects of 1-aminobenzotriazole (ABT) on the excretion of 20-HETE in rats. ABT reduced excretion of 20-HETE by >65% and inhibited the formation of 20-HETE by renal microsomes. The availability of this assay should facilitate work in this field. PMID:10924088

  14. Metabolic fate of arachidonic acid in hepatocytes of continuously endotoxemic rats.

    PubMed Central

    Rodriguez de Turco, E B; Spitzer, J A

    1988-01-01

    The present experiments were designed to characterize the kinetics of [1-14C]arachidonic acid (AA) metabolism as a function of time in hepatocytes obtained from rats infused continuously for 30 h with a nonlethal dose of Escherichia coli endotoxin (ET). Chronic endotoxemia greatly reduces the ability of hepatocytes to utilize [1-14C]AA, which is reflected from the earliest times of incubation in very low labeling of intermediates in the biosynthetic pathways of glycerolipids (phosphatidic acid and diacylglycerol) and slower removal of [1-14C]AA from the free fatty acid pool as compared with saline-infused rats. At later times of incubation, the labeling of phospholipids (especially phosphatidylethanolamine and phosphatidylinositol [PI]), but not of triacylglycerides is decreased. Analysis of fatty acid composition of individual phospholipids from cells of ET-infused rats reveals that the content of AA is significantly reduced only in PI. Hence an impairment in activation/acylation enzymatic mechanisms could affect the turnover of metabolically active phospholipid pools, i.e., PI, involved in signal transmission processes, and result in increased availability of 20:4 for eicosanoid synthesis, contributing to cellular metabolic perturbations in endotoxicosis. PMID:3125225

  15. Production of human milk fat analogue containing docosahexaenoic and arachidonic acids.

    PubMed

    Turan, Dilek; Sahin Yeşilçubuk, Neşe; Akoh, Casimir C

    2012-05-01

    Human milk fat (HMF) analogue containing docosahexaenoic acid (DHA) and arachidonic acid (ARA) at sn-1,3 positions and palmitic acid (PA) at sn-2 position was produced. Novozym 435 lipase was used to produce palmitic acid-enriched hazelnut oil (EHO). EHO was then used to produce the final structured lipid (SL) through interesterification reactions using Lipozyme RM IM. Reaction variables for 3 h reactions were temperature, substrate mole ratio, and ARASCO/DHASCO (A:D) ratio. After statistical analysis of DHA, ARA, total PA, and PA content at sn-2 position, a large-scale production was performed at 60 °C, 3:2 A:D ratio, and 1:0.1 substrate mole ratio. For the SL, those results were determined as 57.3 ± 0.4%, 2.7 ± 0.0%, 2.4 ± 0.1%, and 66.1 ± 2.2%, respectively. Tocopherol contents were 84, 19, 85, and 23 μg/g oil for α-, β-, γ-, and δ-tocopherol. Melting range of SL was narrower than that of EHO. Oxidative stability index (OSI) value of SL (0.80 h) was similar to that of EHO (0.88 h). This SL can be used in infant formulas to provide the benefits of ARA and DHA. PMID:22497589

  16. 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.

  17. 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

  18. Effect of long-term administration of arachidonic acid on n-3 fatty acid deficient mice.

    PubMed

    Harauma, Akiko; Tomita, Makiko; Muto, Daiki; Moriguchi, Toru

    2015-04-01

    The effect of long-term oral administration of arachidonic acid (ARA, 240 mg/kg/day) on brain function was assessed for mice maintained on an n-3 fatty acid adequate or deficient diet. The administration of ARA for 13 weeks resulted in an elevation of spontaneous motor activity, or the tendency thereof, in both the n-3 fatty acid adequate and deficient groups. However, the n-3 fatty acid deficient mice that were administered with ARA revealed marked deterioration in motor function in a motor coordination test. In the experiment to investigate changes over time, the motor activity of the ARA-administered group continued to increase mildly in n-3 deficient mice, although that of the control group showed a decrease involving habituation for both diet groups from the second week. The fatty acid composition of the brain at the end of the behavioral experiments indicated an increase in the levels of ARA and other n-6 fatty acids, as well as a decrease in the levels of docosahexaenoic acid. These results suggest that long-term administration of ARA causes an increase of futile spontaneous motor activity and the diminution of motor function by aggravation of n-3 fatty acid deficiency. PMID:25650363

  19. 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

  20. 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 γ-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

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. Characterization of an arachidonic acid-deficient (Fads1 knockout) mouse model[S

    PubMed Central

    Fan, Yang-Yi; Monk, Jennifer M.; Hou, Tim Y.; Callway, Evelyn; Vincent, Logan; Weeks, Brad; Yang, Peiying; Chapkin, Robert S.

    2012-01-01

    Arachidonic acid (20:4Δ5,8,11,14, AA)-derived eicosanoids regulate inflammation and promote cancer development. Previous studies have targeted prostaglandin enzymes in an attempt to modulate AA metabolism. However, due to safety concerns surrounding the use of pharmaceutical agents designed to target Ptgs2 (cyclooxygenase 2) and its downstream targets, it is important to identify new targets upstream of Ptgs2. Therefore, we determined the utility of antagonizing tissue AA levels as a novel approach to suppressing AA-derived eicosanoids. Systemic disruption of the Fads1 (Δ5 desaturase) gene reciprocally altered the levels of dihomo-γ-linolenic acid (20:3Δ8,11,14, DGLA) and AA in mouse tissues, resulting in a profound increase in 1-series-derived and a concurrent decrease in 2-series-derived prostaglandins. The lack of AA-derived eicosanoids, e.g., PGE2, was associated with perturbed intestinal crypt proliferation, immune cell homeostasis, and a heightened sensitivity to acute inflammatory challenge. In addition, null mice failed to thrive, dying off by 12 weeks of age. Dietary supplementation with AA extended the longevity of null mice to levels comparable to wild-type mice. We propose that this new mouse model will expand our understanding of how AA and its metabolites mediate inflammation and promote malignant transformation, with the eventual goal of identifying new drug targets upstream of Ptgs2. PMID:22534642

  7. 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

  8. Phosphoenolpyruvate Carboxykinase Is an Acid-Induced, Chromosomally Encoded Virulence Factor in Agrobacterium tumefaciens

    PubMed Central

    Liu, Pu; Wood, Derek; Nester, Eugene W.

    2005-01-01

    The pckA gene, encoding phosphoenolpyruvate carboxykinase, catalyzes the reversible decarboxylation and phosphorylation of oxaloacetate to form phosphoenolpyruvate. Located on the circular chromosome of Agrobacterium, this locus is adjacent to the loci chvG and chvI, encoding a two-component regulatory system that has been shown to be important in virulence. Using a reporter gene fusion, studies showed that the pckA gene is induced by acidic pH but not by acetosyringone. This acid induction is regulated by the chvG-chvI regulatory system, which controls acid-inducible genes. A pckA mutant had no demonstrable PckA enzyme activity and grew on AB minimal medium with glucose but did not grow on the same medium with succinate as the sole carbon source and was more inhibited in its growth than the wild-type strain by an acidic environment. A pckA mutant was highly attenuated in tumor-inducing ability on tobacco leaf disks and was severely attenuated in vir gene expression. Although vir gene induction was completely restored when a constitutive virG gene was introduced into the mutant strain, virulence was only partially restored. These results suggest that avirulence may be due to a combination of the inhibition of this mutant in the acidic plant wound environment and the poor induction of the vir genes. PMID:16109945

  9. Acid-induced autophagy protects human lung cancer cells from apoptosis by activating ER stress.

    PubMed

    Xie, Wen-Yue; Zhou, Xiang-Dong; Li, Qi; Chen, Ling-Xiu; Ran, Dan-Hua

    2015-12-10

    An acidic tumor microenvironment exists widely in solid tumors. However, the detailed mechanism of cell survival under acidic stress remains unclear. The aim of this study is to clarify whether acid-induced autophagy exists and to determine the function and mechanism of autophagy in lung cancer cells. We have found that acute low pH stimulated autophagy by increasing LC3-positive punctate vesicles, increasing LC3 II expression levels and reducing p62 protein levels. Additionally, autophagy was inhibited by the addition of Baf or knockdown of Beclin 1, and cell apoptosis was increased markedly. In mouse tumors, the expression of cleaved caspase3 and p62 was enhanced by oral treatment with sodium bicarbonate, which can raise the intratumoral pH. Furthermore, the protein levels of ER stress markers, including p-PERK, p-eIF2?, CHOP, XBP-1s and GRP78, were also increased in response to acidic pH. The antioxidant NAC, which reduces ROS accumulation, alleviated acid-mediated ER stress and autophagy, and knocking down GRP78 reduced autophagy activation under acidic conditions, which suggests that autophagy was induced by acidic pH through ER stress. Taken together, these results indicate that the acidic microenvironment in non-small cell lung cancer cells promotes autophagy by increasing ROS-ER stress, which serves as a survival adaption in this setting. PMID:26559141

  10. The saturated fatty acid, palmitic acid, induces anxiety-like behavior in mice

    PubMed Central

    Moon, Morgan L.; Joesting, Jennifer J.; Lawson, Marcus A.; Chiu, Gabriel S.; Blevins, Neil A.; Kwakwa, Kristin A.; Freund, Gregory G.

    2014-01-01

    Objectives Excess fat in the diet can impact neuropsychiatric functions by negatively affecting cognition, mood and anxiety. We sought to show that the free fatty acid (FFA), palmitic acid, can cause adverse biobehaviors in mice that lasts beyond an acute elevation in plasma FFAs. Methods Mice were administered palmitic acid or vehicle as a single intraperitoneal (IP) injection. Biobehaviors were profiled 2 and 24 hrs after palmitic acid treatment. Quantification of dopamine (DA), norepinephrine (NE), serotonin (5-HT) and their major metabolites was performed in cortex, hippocampus and amygdala. FFA concentration was determined in plasma. Relative fold change in mRNA expression of unfolded protein response (UPR)-associated genes was determined in brain regions. Results In a dose-dependent fashion, palmitic acid rapidly reduced mouse locomotor activity by a mechanism that did not rely on TLR4, MyD88, IL-1, IL-6 or TNFα but was dependent on fatty acid chain length. Twenty-four hrs after palmitic acid administration mice exhibited anxiety-like behavior without impairment in locomotion, food intake, depressive-like behavior or spatial memory. Additionally, the serotonin metabolite 5-HIAA was increased by 33% in the amygdala 24 hrs after palmitic acid treatment. Conclusions Palmitic acid induces anxiety-like behavior in mice while increasing amygdala-based serotonin metabolism. These effects occur at a time point when plasma FFA levels are no longer elevated. PMID:25016520

  11. Folic acid induces salicylic acid-dependent immunity in Arabidopsis and enhances susceptibility to Alternaria brassicicola.

    PubMed

    Wittek, Finni; Kanawati, Basem; Wenig, Marion; Hoffmann, Thomas; Franz-Oberdorf, Katrin; Schwab, Wilfried; Schmitt-Kopplin, Philippe; Vlot, A Corina

    2015-08-01

    Folates are essential for one-carbon transfer reactions in all organisms and contribute, for example, to de novo DNA synthesis. Here, we detected the folate precursors 7,8-dihydropteroate (DHP) and 4-amino-4-deoxychorismate (ADC) in extracts from Arabidopsis thaliana plants by Fourier transform ion cyclotron resonance-mass spectrometry. The accumulation of DHP, but not ADC, was induced after infection of plants with Pseudomonas syringae delivering the effector protein AvrRpm1. Application of folic acid or the DHP precursor 7,8-dihydroneopterin (DHN) enhanced resistance in Arabidopsis to P. syringae and elevated the transcript accumulation of the salicylic acid (SA) marker gene pathogenesis-related1 in both the treated and systemic untreated leaves. DHN- and folic acid-induced systemic resistance was dependent on SA biosynthesis and signalling. Similar to SA, folic acid application locally enhanced Arabidopsis susceptibility to the necrotrophic fungus Alternaria brassicicola. Together, the data associate the folic acid pathway with innate immunity in Arabidopsis, simultaneously activating local and systemic SA-dependent resistance to P. syringae and suppressing local resistance to A. brassicicola. PMID:25348251

  12. Butyric acid-induced apoptosis of murine thymocytes, splenic T cells, and human Jurkat T cells.

    PubMed Central

    Kurita-Ochiai, T; Fukushima, K; Ochiai, K

    1997-01-01

    The purpose of this study was to examine the effect of butyric acid, an extracellular metabolite from periodontopathic bacteria, on apoptosis induction in murine thymocytes, splenic T cells, and human Jurkat T cells. Butyric acid significantly suppressed T-cell viability in both a concentration- and time-dependent fashion. The results of DNA fragmentation assay indicated that butyric acid rapidly induced apoptosis in thymocytes (with 1.25 mM butyric acid and 6 h after treatment) and in splenic T cells and Jurkat cells (with 2.5 mM butyric acid and 16 h after treatment). Incubation of thymocytes or Jurkat cells with 5 mM butyric acid for 21 h resulted in the typical ladder pattern of DNA fragmentation. Furthermore, Jurkat cells treated with 5 mM butyric acid showed the characteristic pattern of apoptotic cells such as chromatin condensation and hypodiploid nuclei. Experiments with fractionated subpopulations of splenic T cells revealed that DNA fragmentation was predominantly observed in CD4+ T cells. Butyric acid-induced apoptosis of thymocytes was decreased by the protein kinase inhibitors H7 and staurosporine. These inhibitors were less effective with similarly treated splenic T cells and Jurkat cells. These data suggest that butyric acid, one of the volatile fatty acids produced by periodontopathic bacteria and one that easily penetrates the oral mucosa, can modulate the immunoregulatory cell population in periodontal tissue by inducing T-cell death through apoptosis. PMID:8975889

  13. Ulcer healing activity of Mumijo aqueous extract against acetic acid induced gastric ulcer in rats

    PubMed Central

    Shahrokhi, Nader; Keshavarzi, Zakieh; Khaksari, Mohammad

    2015-01-01

    Objective: Gastric ulcer is an important clinical problem, chiefly due to extensive use of some drugs. The aim was to assess the activity of Mumijo extract (which is used in traditional medicine) against acetic acid induced gastric ulcer in rats. Materials and Methods: The aqueous extract of Mumijo was prepared. Animals were randomly (n = 10) divided into four groups: Control, sham-operated group (received 0.2 ml of acetic acid to induce gastric ulcer), Mumijo (100 mg/kg/daily) were given for 4 days postacetic acid administration, and ranitidine group (20 mg/kg). The assessed parameters were pH and pepsin levels (by Anson method) of gastric contents and gastric histopathology. Ranitidine was used as reference anti-ulcer drug. Results: The extract (100 mg/kg/daily, p.o.) inhibited acid acetic-induced gastric ulceration by elevating its pH versus sham group (P < 0.01) and decreasing the pepsin levels compared to standard drug, ranitidine (P < 0.05). The histopathology data showed that the treatment with Mumijo extract had a significant protection against all mucosal damages. Conclusion: Mumijo extract has potent antiulcer activity. Its anti-ulcer property probably acts via a reduction in gastric acid secretion and pepsin levels. The obtained results support the use of this herbal material in folk medicine. PMID:25709338

  14. Quinolinic acid induces cell apoptosis in PC12 cells through HIF-1-dependent RTP801 activation.

    PubMed

    Huang, Xiaojia; Yang, Kaiyong; Zhang, Yi; Wang, Qiang; Li, Yongjin

    2016-04-01

    Neurological disease comprises a series of disorders featuring brain dysfunction and neuronal cell death. Among the factors contributing to neuronal death, excitotoxicity induced by excitatory amino acids, such as glutamate, plays a critical role. However, the mechanisms about how the excitatory amino acids induce neuronal death remain elucidated. In this study, we investigated the role of HIF-1α (hypoxia inducible factor-1α) and RTP801 in cell apoptosis induced by quinolinic acid (QUIN), a glutamatergic agonist, in PC12 cells. We found that QUIN at 5 μM increased the expression of HIF-1α significantly with a peak at 24 h. After the treatment with QUIN (5-20 μM) for 24 h, the cells exhibited decreased viability and cell apoptosis with a concomitant increased expression of apoptosis related proteins. QUIN treatment also induced the generation of intracellular reactive oxygen species and RTP801 up-regulation in a HIF-1α-dependent manner that were inhibited by 2-methoxyestradiol, a HIF-1α inhibitor. Importantly, HIF-1 or RTP801 invalidation by siRNA rescued the cell apoptosis induced by QUIN or cobalt chloride, a chemical inducer of HIF-1. Taken together, these findings support the concept that neurotoxicity induced by QUIN is associated with HIF-1-dependent RTP801 activation and provide insight into the potential of RTP801 inhibitor in treatment of neurological disorders. PMID:26738727

  15. 4-Hydroxyisoleucine ameliorates fatty acid-induced insulin resistance and inflammatory response in skeletal muscle cells.

    PubMed

    Maurya, Chandan Kumar; Singh, Rohit; Jaiswal, Natasha; Venkateswarlu, K; Narender, Tadigoppula; Tamrakar, Akhilesh Kumar

    2014-09-01

    The 4-hydroxyisoleucine (4-HIL), an unusual amino acid isolated from the seeds of Trigonella foenum-graecum was investigated for its metabolic effects to ameliorate free fatty acid-induced insulin resistance in skeletal muscle cells. An incubation of L6 myotubes with palmitate inhibited insulin stimulated-glucose uptake and -translocation of glucose transporter 4 (GLUT4) to the cell surface. Addition of 4-HIL strongly prevented this inhibition. We then examined the insulin signaling pathway, where 4-HIL effectively inhibited the ability of palmitate to reduce insulin-stimulated phosphorylation of insulin receptor substrate-1 (IRS-1), protein kinase B (PKB/AKT), AKT substrate of 160?kD (AS160) and glycogen synthase kinase 3? (GSK-3?) in L6 myotubes. Moreover, 4-HIL presented strong inhibition on palmitate-induced production of reactive oxygen species (ROS) and associated inflammation, as the activation of NF-?B, JNK1/2, ERK1/2 and p38 MAPK was greatly reduced. 4-HIL also inhibited inflammation-stimulated IRS-1 serine phosphorylation and restored insulin-stimulated IRS-1 tyrosine phosphorylation in the presence of palmitate, leading to enhanced insulin sensitivity. These findings suggested that 4-HIL could inhibit palmitate-induced, ROS-associated inflammation and restored insulin sensitivity through regulating IRS-1 function. PMID:25109277

  16. Oleic acid-induced lung injury in rabbits: effect of fibrinogen depletion with Arvin

    SciTech Connect

    Allard, M.F.; Doerschuk, C.M.; Brumwell, M.L.; Belzberg, A.; Hogg, J.C.

    1988-03-01

    The role of fibrinogen in the evolution of the increased permeability after oleic acid-induced lung injury was studied in New Zealand White rabbits. Animals depleted of fibrinogen by treatment with Malayan pit viper venom were compared with untreated rabbits immediately and at 1 and 24 h after injury. The increased permeability to albumin and elevated extravascular lung water (EVLW) associated with lung injury returned to control values by 24 h in untreated animals. Fibrinogen-depleted animals had a higher mortality (10/25 vs. 2/17, P less than 0.02) and showed a greater immediate increase in permeability to albumin that returned to control values at 1 and 24 h after injury, as well as trends toward elevated blood-free dry lung weight and larger increases in EVLW that persisted for 24 h. These findings indicate that fibrinogen-related proteins play an important role in controlling the microvascular injury that is produced by oleic acid. However, when these proteins are depleted, other mechanisms partially control the leak at later stages of the repair process.

  17. Saturated phosphatidic acids mediate saturated fatty acid-induced vascular calcification and lipotoxicity.

    PubMed

    Masuda, Masashi; Miyazaki-Anzai, Shinobu; Keenan, Audrey L; Okamura, Kayo; Kendrick, Jessica; Chonchol, Michel; Offermanns, Stefan; Ntambi, James M; Kuro-O, Makoto; Miyazaki, Makoto

    2015-12-01

    Recent evidence indicates that saturated fatty acid-induced (SFA-induced) lipotoxicity contributes to the pathogenesis of cardiovascular and metabolic diseases; however, the molecular mechanisms that underlie SFA-induced lipotoxicity remain unclear. Here, we have shown that repression of stearoyl-CoA desaturase (SCD) enzymes, which regulate the intracellular balance of SFAs and unsaturated FAs, and the subsequent accumulation of SFAs in vascular smooth muscle cells (VSMCs), are characteristic events in the development of vascular calcification. We evaluated whether SMC-specific inhibition of SCD and the resulting SFA accumulation plays a causative role in the pathogenesis of vascular calcification and generated mice with SMC-specific deletion of both Scd1 and Scd2. Mice lacking both SCD1 and SCD2 in SMCs displayed severe vascular calcification with increased ER stress. Moreover, we employed shRNA library screening and radiolabeling approaches, as well as in vitro and in vivo lipidomic analysis, and determined that fully saturated phosphatidic acids such as 1,2-distearoyl-PA (18:0/18:0-PA) mediate SFA-induced lipotoxicity and vascular calcification. Together, these results identify a key lipogenic pathway in SMCs that mediates vascular calcification. PMID:26517697

  18. Effect of galactose on acid induced molten globule state of Soybean Agglutinin: Biophysical approach

    NASA Astrophysics Data System (ADS)

    Alam, Parvez; Naseem, Farha; Abdelhameed, Ali Saber; Khan, Rizwan Hasan

    2015-11-01

    In the present study the formation of molten globule-like unfolding intermediate Soybean Agglutinin (SBA) in acidic pH range has been established with the help of acrylamide quenching, intrinsic fluorescence, ANS fluorescence measurement, far UV CD and dynamic light scattering measurement. A marked increase in ANS fluorescence was observed at pH 2.2. Ksv of acrylamide quenching was found to be higher at pH 2.2 than that of native SBA at pH 7. Far UV CD spectra of pH induced state suggest that SBA shows significant retention of secondary structure closure to native. Hydrodynamic radius of SBA at pH 2.2 was found be more as compared to native state and also in other pH induced states. Further we checked the effect of galactose on the molten globule state of SBA. This study suggests that SBA exist as molten globule at pH 2.2 and this study will help in acid induced molten globule state of other proteins.

  19. Anacardic acid induces apoptosis-like cell death in the rice blast fungus Magnaporthe oryzae.

    PubMed

    Muzaffar, Suhail; Bose, Chinchu; Banerji, Ashok; Nair, Bipin G; Chattoo, Bharat B

    2016-01-01

    Anacardic acid (6-pentadecylsalicylic acid), extracted from cashew nut shell liquid, is a natural phenolic lipid well known for its strong antibacterial, antioxidant, and anticancer activities. Its effect has been well studied in bacterial and mammalian systems but remains largely unexplored in fungi. The present study identifies antifungal, cytotoxic, and antioxidant activities of anacardic acid in the rice blast fungus Magnaporthe oryzae. It was found that anacardic acid causes inhibition of conidial germination and mycelial growth in this ascomycetous fungus. Phosphatidylserine externalization, chromatin condensation, DNA degradation, and loss of mitochondrial membrane potential suggest that growth inhibition of fungus is mainly caused by apoptosis-like cell death. Broad-spectrum caspase inhibitor Z-VAD-FMK treatment indicated that anacardic acid induces caspase-independent apoptosis in M. oryzae. Expression of a predicted ortholog of apoptosis-inducing factor (AIF) was upregulated during the process of apoptosis, suggesting the possibility of mitochondria dependent apoptosis via activation of apoptosis-inducing factor. Anacardic acid treatment leads to decrease in reactive oxygen species rather than increase in reactive oxygen species (ROS) accumulation normally observed during apoptosis, confirming the antioxidant properties of anacardic acid as suggested by earlier reports. Our study also shows that anacardic acid renders the fungus highly sensitive to DNA damaging agents like ethyl methanesulfonate (EMS). Treatment of rice leaves with anacardic acid prevents M. oryzae from infecting the plant without affecting the leaf, suggesting that anacardic acid can be an effective antifungal agent. PMID:26381667

  20. The Massachusetts Eye and Ear Infirmary, Boston.

    PubMed

    Mardell, A

    1995-09-01

    It was a wet and grey day in downtown Boston. It was reported on the six o'clock news that a record 2.7 inches of rain fell on the city that day. Much of it seemed to have fallen on me as I drove in from the suburbs. I had come all this way on a long anticipated holiday to see 'The Fall' in New England but there was something about the rain that was strangely reminiscent of our home grown variety in Wales. Should I perhaps have stayed at home with some videos and books? It would certainly have been cheaper. I had arranged to visit the 'Eye and Ear' some weeks before. The link being one of my consultant colleagues who had undergone some of his training as a resident there many years before, under the guidance of the famous Dr. Harold Schucneckt. I wanted to see what things were like in hospitals and operating theatres and get a taste of the American nursing and healthcare system. PMID:7663057

  1. Tricellular Tight Junctions in the Inner Ear

    PubMed Central

    2016-01-01

    Tight junctions (TJs) are structures that seal the space between the epithelial cell sheets. In the inner ear, the barrier function of TJs is indispensable for the separation of the endolymphatic and perilymphatic spaces, which is essential for the generation and maintenance of the endocochlear potential (EP). TJs are formed by the intercellular binding of membrane proteins, known as claudins, and mutations in these proteins cause deafness in humans and mice. Within the epithelial cell sheet, however, a bound structure is present at the site where the corners of three cells meet (tricellular tight junctions (tTJs)), and the maintenance of the barrier function at this location cannot be explained by the claudins alone. Tricellulin and the angulin family of proteins (angulin-1/LSR, angulin-2/ILDR1, and angulin-3/ILDR2) have been identified as tTJ-associated proteins. Tricellulin and ILDR1 are localized at the tTJ and alterations in these proteins have been reported to be involved in deafness. In this review, we will present the current state of knowledge for tTJs. PMID:27195292

  2. 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

  3. 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 = γ ITD for constant 1 < γ < 5 and variable input frequency <ν∘ follows; e.g., for the Tockay gecko ν∘ ~ 1 . 5 kHz. Third, we use a sectorial instead of circular membrane to quantify the effect of the extracolumella embedded in the tympanum and connecting with the cochlea. The main parameters can be adjusted so that the model is species independent. Work done in collaboration with A.P. Vedurmudi and J. Goulet; partially supported by BCCN-Munich.

  4. 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.

  5. NARSTO PAC2001 GOLDEN EARS GAS PM DATA

    Atmospheric Science Data Center

    2014-04-25

    NARSTO PAC2001 GOLDEN EARS GAS PM DATA Project Title:  NARSTO Discipline:  ... Station, Ground Station Instrument:  Pressure Sensor Temperature Probe Humidity Sensor Wind Sensor UV Ozone Detector Chemiluminescence DMA GC-MS ...

  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. Revision Stapedectomy in a Female Patient with Inner Ear Malformation

    PubMed Central

    Patel, Tirth R.; Moberly, Aaron C.

    2016-01-01

    Objectives. We describe an unusual case of surgical management of congenital mixed hearing loss in a female patient with inner ear malformation. This report outlines the role of temporal bone imaging and previous surgical history in evaluating a patient's risk of perilymph gusher during stapes surgery. Methods. A 68-year-old female patient with a history of profound bilateral mixed hearing loss due to ossicular and cochlear malformation presented to our otology clinic. She had undergone multiple unsuccessful previous ear surgeries. Computed tomography revealed bilateral inner ear malformations. She elected to proceed with revision stapedectomy. Results. The patient received modest benefit to hearing, and no operative complications occurred. Conclusions. Although stapedectomy has been shown to improve hearing in patients with stapes fixation, there is risk of perilymph gusher in patients with inner ear abnormalities. Evaluation and counseling of the risk of gusher during stapes surgery should be done on a case-by-case basis. PMID:27144044

  8. Forgotten T-tube in the middle ear.

    PubMed

    Shakeel, Muhammad; Trinidade, Aaron; Khan, Imran; Ah-See, Kim Wong

    2012-05-01

    Retention within the middle ear cleft is an unusual complication of T-tube insertion. A 40-year-old woman with Kartagener's Syndrome presented with hearing impairment in the right ear. She was found to have a previously inserted Goode T-tube lying within the middle ear behind an intact drum. She underwent successful removal of the T-tube via a myringotomy, and a new tube was re-inserted. Migration of a T-tube into the middle ear cleft should always be kept in mind in patients who present with otological symptoms and have a history of T-tube insertion, even in the presence of an intact drum. PMID:22538046

  9. How minute sooglossid frogs hear without a middle ear.

    PubMed

    Boistel, Renaud; Aubin, Thierry; Cloetens, Peter; Peyrin, Françoise; Scotti, Thierry; Herzog, Philippe; Gerlach, Justin; Pollet, Nicolas; Aubry, Jean-François

    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

  10. 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.

  11. [Aural polyp in chronic inflammatory middle ear disease].

    PubMed

    López Aguado, D; López Campos, D; Pérez Piñero, B; Campos Bañales, M E

    2003-03-01

    240 patients with chronic otitis media (COM) were studied: 166 ears termed as non cholesteatomatous otitis media and 74 with cholesteatoma. In 38 ears an aural polyp was found with no evidence of cholesteatoma in 19 ears (11.4%) whereas a cholesteatoma was present in the remaining 19 ears. The histology of the polyp and the characteristics of the chronic process were matched: a) The aural polyp is an infrequent complication in COM. b) After histological analysis was found to present two different pictures: The inflammatory reaction polyp, present in non cholesteatomatous COM; and the polyp with granulation tissue and foreign body reaction (keratina) usually found in cholesteatomatous COM. c) The finding of granulation tissue reaction and keratina in an aural polyp is a good predictor for the presence of a cholesteatoma. PMID:12825338

  12. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 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 throat... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat microsurgical carbon...

  13. 21 CFR 874.4250 - Ear, nose, and throat electric or pneumatic surgical drill.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 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, and... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat electric or...

  14. 21 CFR 874.4350 - Ear, nose, and throat fiberoptic light source and carrier.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 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 throat... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat fiberoptic light source...

  15. 21 CFR 874.4250 - Ear, nose, and throat electric or pneumatic surgical drill.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 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, and... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat electric or...

  16. 21 CFR 874.4500 - Ear, nose, and throat microsurgical carbon dioxide laser.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 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 throat... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat microsurgical carbon...

  17. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 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 throat... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Ear, nose, and throat examination and...

  18. 21 CFR 874.5300 - Ear, nose, and throat examination and treatment unit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 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 throat... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat examination and...

  19. 21 CFR 874.4350 - Ear, nose, and throat fiberoptic light source and carrier.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 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 throat... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ear, nose, and throat fiberoptic light source...

  20. 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...

  1. 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...

  2. 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,...

  3. 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...

  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 874.5300 - 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...

  6. 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...

  7. 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,...

  8. 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,...

  9. 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...

  10. 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...

  11. 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...

  12. 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...

  13. 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...

  14. 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...

  15. SHIELD: an integrative gene expression database for inner ear research

    PubMed Central

    Shen, Jun; Scheffer, Déborah 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

  16. Ear keloids: a review and update of treatment options

    PubMed Central

    SOBEC, RALUCA; DOBREANU, CODRIN; FODOR, LUCIAN; ŞOMCUTEAN, ANA; ŢICHIL, IOANA; COSGAREA, MARCEL

    2013-01-01

    Ear keloids are among the most challenging plastic surgery conditions and may have significant psychosocial impact for the patient. Their aesthetic considerations are serious and despite a variety of treatment options, they often proved to be recurrent. This paper reviews the management options of ear keloids available in literature up to date. Multiple therapeutic options are discussed, such as: surgical treatment, corticosteroid injections, laser therapy, cryotherapy, radiotherapy, pressure therapy, therapy with antitumor or immunosuppressive agents. PMID:26527968

  17. SHIELD: an integrative gene expression database for inner ear research.

    PubMed

    Shen, Jun; Scheffer, Déborah 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. 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

  19. Prevalence of middle ear disorders in coal miners

    SciTech Connect

    Lempert, B.L.; Hopkinson, N.T.; Keith, R.W.; Motl, M.L.; Horine, J.

    1981-06-01

    Results are presented from a study of the prevalence of middle and external ear disorders in coal miners who work underground. The study followed from an earlier NIOSH report (1976) that indicated a possibly large number of otoscopic abnormalities in this population of workers. Otoscopic examinations, pure tone air- and bone-conduction audiometry tests, and impedance tests were administered to 350 underground miners and 150 industrial workers not associated with mining. The study was conducted completely within a hospital otolaryngology/audiology clinic setting. Results of the investigation showed a highly similar prevalence of middle ear and ear canal abnormalities in the miner group and the control group (19 percent). Middle ear abnormalities observed in the miners were judged by the examining otolaryngologists to have preceded their experience in the mines and were not related solely to underground noise exposure or coal dust. Nearly half of the subjects who had an air-bone gap had no middle ear abnormality observable by otoscopic examination. There was substantial agreement between the finding of abnormal otoscopy and abnormal tympanometry. By itself, acoustic reflex was not useful in identifying middle ear disorders, since this reflex may be absent for other reasons, including presence of severe sensorineural hearing loss.

  20. Lumped parametric model of the human ear for sound transmission.

    PubMed

    Feng, Bin; Gan, Rong Z

    2004-09-01

    A lumped parametric model of the human auditoria peripherals consisting of six masses suspended with six springs and ten dashpots was proposed. This model will provide the quantitative basis for the construction of a physical model of the human middle ear. The lumped model parameters were first identified using published anatomical data, and then determined through a parameter optimization process. The transfer function of the middle ear obtained from human temporal bone experiments with laser Doppler interferometers was used for creating the target function during the optimization process. It was found that, among 14 spring and dashpot parameters, there were five parameters which had pronounced effects on the dynamic behaviors of the model. The detailed discussion on the sensitivity of those parameters was provided with appropriate applications for sound transmission in the ear. We expect that the methods for characterizing the lumped model of the human ear and the model parameters will be useful for theoretical modeling of the ear function and construction of the ear physical model. PMID:15300453

  1. Erythema associated with pain and warmth on face and ears: a variant of erythermalgia or red ear syndrome?

    PubMed Central

    2014-01-01

    Erythermalgia is a rare cutaneous disorder characterized by attacking of erythema, pain and increased temperature, which primarily involves the extremities and may infrequently extend to the neck, face, ears and even the scrotum. We reported an 18-year-old woman who presented with 3 years history of sole involvement of attacking erythema, pain and warmth over her face and ears without any other associations. The frequency and severity of the flares progressed gradually during the course. Cutaneous examination revealed erythema, increased temperature and tenderness on the face and ears during the flare. The symptoms could be relieved rapidly by cooling. Dermatoscope showed that vessels inside the erythema were more dilated during the episode than after application of ice. The lesion is considered a rare variant of erythermalgia with sole involvement of face and ears. The symptoms had mild response to oral antihistamines, topical steroids and tacrolimus, but had excellent response to the combinative therapy of aspirin and paroxetins. PMID:24670221

  2. Real ear unaided gain and its relation with the equivalent volume of the external and middle ear

    PubMed Central

    Bastos, Bárbara Guimarães; Ferrari, Deborah Viviane; Blasc, Wanderléia Quinhoneiro

    2012-01-01

    Summary Introduction: Old age is associated with changes in the characteristics of the middle ear transmission system and in external ear resonance, and these carry implications for the hearing aid (HA) verification process for which targets and measures of the real ear insertion gain (REIG) are used. Aim: To compare the real ear unaided gain (REUG) and the equivalent volumes of the external ear (VeqEE) and the middle ear (VeqME) between elderly and adult patients. Methods: This is a retrospective study in which the medical records of 28 elderly patients (aged between 61 and 102 years, average hearing thresholds between 38.75 and 85 dB HL) and 23 adult patients (aged 20–59, mean hearing thresholds between 31.25 and 116.25 dB HL) with bilateral sensorineural hearing loss and no history of middle ear abnormalities were analyzed. Immittance measurements (VeqEE, VeqME, and pressure of the peak of maximum compliance) and the REUG (frequency and amplitude of the primary peak) were recovered for a total of 40 ears. These data were compared between elderly and adults as well as between men and women, using Student's t test. Correlations (Pearson) between immittance and REUG data were also verified. Results: No statistically significant differences (p < 0.01) were found for immittance and REUG data between elderly and adults, or between men and women. A negative and weak but significant correlation was observed between the REUG primary peak and VeqEE. Conclusion: Hearing aid verification can be performed with target and measures of the REIG in the elderly population. PMID:25991959

  3. FT-IR Microspectroscopy of Rat Ear Cartilage

    PubMed Central

    Vidal, Benedicto de Campos; Mello, Maria Luiza S.

    2016-01-01

    Rat ear cartilage was studied using Fourier transform-infrared (FT-IR) microspectroscopy to expand the current knowledge which has been established for relatively more complex cartilage types. Comparison of the FT-IR spectra of the ear cartilage extracellular matrix (ECM) with published data on articular cartilage, collagen II and 4-chondroitin-sulfate standards, as well as of collagen type I-containing dermal collagen bundles (CBs) with collagen type II, was performed. Ear cartilage ECM glycosaminoglycans (GAGs) were revealed histochemically and as a reduction in ECM FT-IR spectral band heights (1140–820 cm-1) after testicular hyaluronidase digestion. Although ear cartilage is less complex than articular cartilage, it contains ECM components with a macromolecular orientation as revealed using polarization microscopy. Collagen type II and GAGs, which play a structural role in the stereo-arrangement of the ear cartilage, contribute to its FT-IR spectrum. Similar to articular cartilage, ear cartilage showed that proteoglycans add a contribution to the collagen amide I spectral region, a finding that does not recommend this region for collagen type II quantification purposes. In contrast to articular cartilage, the symmetric stretching vibration of –SO3- groups at 1064 cm-1 appeared under-represented in the FT-IR spectral profile of ear cartilage. Because the band corresponding to the asymmetric stretching vibration of –SO3- groups (1236–1225 cm-1) overlapped with that of amide III bands, it is not recommended for evaluation of the –SO3- contribution to the FT-IR spectrum of the ear cartilage ECM. Instead, a peak (or shoulder) at 1027–1016 cm-1 could be better considered for this intent. Amide I/amide II ratios as calculated here and data from the literature suggest that protein complexes of the ear cartilage ECM are arranged with a lower helical conformation compared to pure collagen II. The present results could motivate further studies on this tissue under pathological or experimental states involving ear cartilage. PMID:27015280

  4. FT-IR Microspectroscopy of Rat Ear Cartilage.

    PubMed

    Vidal, Benedicto de Campos; Mello, Maria Luiza S

    2016-01-01

    Rat ear cartilage was studied using Fourier transform-infrared (FT-IR) microspectroscopy to expand the current knowledge which has been established for relatively more complex cartilage types. Comparison of the FT-IR spectra of the ear cartilage extracellular matrix (ECM) with published data on articular cartilage, collagen II and 4-chondroitin-sulfate standards, as well as of collagen type I-containing dermal collagen bundles (CBs) with collagen type II, was performed. Ear cartilage ECM glycosaminoglycans (GAGs) were revealed histochemically and as a reduction in ECM FT-IR spectral band heights (1140-820 cm-1) after testicular hyaluronidase digestion. Although ear cartilage is less complex than articular cartilage, it contains ECM components with a macromolecular orientation as revealed using polarization microscopy. Collagen type II and GAGs, which play a structural role in the stereo-arrangement of the ear cartilage, contribute to its FT-IR spectrum. Similar to articular cartilage, ear cartilage showed that proteoglycans add a contribution to the collagen amide I spectral region, a finding that does not recommend this region for collagen type II quantification purposes. In contrast to articular cartilage, the symmetric stretching vibration of -SO3- groups at 1064 cm-1 appeared under-represented in the FT-IR spectral profile of ear cartilage. Because the band corresponding to the asymmetric stretching vibration of -SO3- groups (1236-1225 cm-1) overlapped with that of amide III bands, it is not recommended for evaluation of the -SO3- contribution to the FT-IR spectrum of the ear cartilage ECM. Instead, a peak (or shoulder) at 1027-1016 cm-1 could be better considered for this intent. Amide I/amide II ratios as calculated here and data from the literature suggest that protein complexes of the ear cartilage ECM are arranged with a lower helical conformation compared to pure collagen II. The present results could motivate further studies on this tissue under pathological or experimental states involving ear cartilage. PMID:27015280

  5. Intrarenal renin-angiotensin system mediates fatty acid-induced ER stress in the kidney.

    PubMed

    Li, Chunling; Lin, Yu; Luo, Renfei; Chen, Shaoming; Wang, Feifei; Zheng, Peili; Levi, Moshe; Yang, Tianxin; Wang, Weidong

    2016-03-01

    Obesity-related kidney disease is related to caloric excess promoting deleterious cellular responses. Accumulation of saturated free fatty acids in tubular cells produces lipotoxicity involving significant cellular dysfunction and injury. The objectives of this study were to elucidate the role of renin-angiotensin system (RAS) activation in saturated fatty acid-induced endoplasmic reticulum (ER) stress in cultured human proximal tubule epithelial cells (HK2) and in mice fed with a high-fat diet. Treatment with saturated fatty acid palmitic acid (PA; 0.8 mM) for 24 h induced ER stress in HK2, leading to an unfolded protein response as reflected by increased expressions of the ER chaperone binding immunoglobulin protein (BiP) and proapoptotic transcription factor C/EBP homologous protein (CHOP) protein as evaluated by immunoblotting. PA treatment also induced increased protein expression of inositol requiring protein 1α (IRE1α), phosphorylated eukaryotic initiation factor-α (eIF2α), and activating transcription factor 4 (ATF4) as well as activation of caspase-3. PA treatment was associated with increased angiotensin II levels in cultured medium. The angiotensin II type 1 receptor (AT1R) blocker valsartan or renin inhibitor aliskiren dramatically suppressed PA-induced upregulation of BiP, CHOP, IRE1α, p-eIF2α, and ATF4 in HK2 cells. In contrast, valsartan or aliskiren did not prevent ER stress induced by tunicamycin. C57BL/6 mice fed with a high-fat diet for 14 wk exhibited increased protein expressions of BiP and CHOP compared with control mice, which were significantly attenuated by the valsartan treatment. Increased angiotensin II levels in serum and urine were observed in mice fed with a high-fat diet when compared with controls. It is suggested that the intrarenal RAS activation may play an important role in diabetic kidney injury via mediating ER stress induced by saturated fatty acid. PMID:26672616

  6. Lysophosphatidic acid induces vasodilation mediated by LPA1 receptors, phospholipase C, and endothelial nitric oxide synthase

    PubMed Central

    Ruisanchez, Éva; Dancs, Péter; Kerék, Margit; Németh, Tamás; Faragó, Bernadett; Balogh, Andrea; Patil, Renukadevi; Jennings, Brett L.; Liliom, Károly; Malik, Kafait U.; Smrcka, Alan V.; Tigyi, Gabor; Benyó, Zoltán

    2014-01-01

    Lysophosphatidic acid (LPA) has been implicated as a mediator of several cardiovascular functions, but its potential involvement in the control of vascular tone is obscure. Here, we show that both LPA (18:1) and VPC31143 (a synthetic agonist of LPA1–3 receptors) relax intact mouse thoracic aorta with similar Emax values (53.9 and 51.9% of phenylephrine-induced precontraction), although the EC50 of LPA- and VPC31143-induced vasorelaxations were different (400 vs. 15 nM, respectively). Mechanical removal of the endothelium or genetic deletion of endothelial nitric oxide synthase (eNOS) not only diminished vasorelaxation by LPA or VPC31143 but converted it to vasoconstriction. Freshly isolated mouse aortic endothelial cells expressed LPA1, LPA2, LPA4 and LPA5 transcripts. The LPA1,3 antagonist Ki16425, the LPA1 antagonist AM095, and the genetic deletion of LPA1, but not that of LPA2, abolished LPA-induced vasorelaxation. Inhibition of the phosphoinositide 3 kinase–protein kinase B/Akt pathway by wortmannin or MK-2206 failed to influence the effect of LPA. However, pharmacological inhibition of phospholipase C (PLC) by U73122 or edelfosine, but not genetic deletion of PLCε, abolished LPA-induced vasorelaxation and indicated that a PLC enzyme, other than PLCε, mediates the response. In summary, the present study identifies LPA as an endothelium-dependent vasodilator substance acting via LPA1, PLC, and eNOS.—Ruisanchez, É., Dancs, P., Kerék, M., Németh, T., Faragó, B., Balogh, A., Patil, R., Jennings, B. L., Liliom, K., Malik, K. U., Smrcka, A. V., Tigyi, G., Benyó, Z. Lysophosphatidic acid induces vasodilation mediated by LPA1 receptors, phospholipase C, and endothelial nitric oxide synthase. PMID:24249637

  7. A dual inhibitor of cyclooxygenase and 5-lipoxygenase protects against kainic acid-induced brain injury.

    PubMed

    Minutoli, Letteria; Marini, Herbert; Rinaldi, Mariagrazia; Bitto, Alessandra; Irrera, Natasha; Pizzino, Gabriele; Pallio, Giovanni; Calò, Margherita; Adamo, Elena Bianca; Trichilo, Vincenzo; Interdonato, Monica; Galfo, Federica; Squadrito, Francesco; Altavilla, Domenica

    2015-06-01

    Systemic administration of kainic acid causes inflammation and apoptosis in the brain, resulting in neuronal loss. Dual cyclooxygenase/5-lipoxygenase (COX/5-LOX) inhibitors could represent a possible neuroprotective approach in preventing glutamate excitotoxicity. Consequently, we investigated the effects of a dual inhibitor of COX/5-LOX following intraperitoneal administration of kainic acid (KA, 10 mg/kg) in rats. Animals were randomized to receive either the dual inhibitor of COX/5-LOX (flavocoxid, 20 mg/kg i.p.) or its vehicle (1 ml/kg i.p.) 30 min after KA administration. Sham brain injury rats were used as controls. We evaluated protein expression of phosphorylated extracellular signal-regulated kinase (p-ERK1/2) and tumor necrosis factor alpha (TNF-α) as well as levels of malondialdehyde (MDA), prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) in the hippocampus. Animals were also observed for monitoring behavioral changes according to Racine Scale. Finally, histological analysis and brain edema evaluation were carried out. Treatment with the dual inhibitor of COX/5-LOX decreased protein expression of p-ERK1/2 and TNF-α in hippocampus, markedly reduced MDA, LTB4 and PGE2 hippocampal levels, and also ameliorated brain edema. Histological analysis showed a reduction in cell damage in rats treated with the dual inhibitor of COX/5-LOX, particularly in hippocampal subregion CA3c. Moreover, flavocoxid significantly improved behavioral signs following kainic acid administration. Our results suggest that dual inhibition of COX/5-LOX by flavocoxid has neuroprotective effects during kainic acid-induced excitotoxicity. PMID:25893744

  8. Bile Acid-Induced Necrosis in Primary Human Hepatocytes and in Patients with Obstructive Cholestasis

    PubMed Central

    Woolbright, Benjamin L.; Dorko, Kenneth; Antoine, Daniel J.; Clarke, Joanna I.; Gholami, Parviz; Li, Feng; Kumer, Sean C.; Schmitt, Timothy M.; Forster, Jameson; Fan, Fang; Jenkins, Rosalind E.; Park, B. Kevin; Hagenbuch, Bruno; Olyaee, Mojtaba; Jaeschke, Hartmut

    2015-01-01

    Accumulation of bile acids is a major mediator of cholestatic liver injury. Recent studies indicate bile acid composition between humans and rodents is dramatically different, as humans have a higher percent of glycine conjugated bile acids and increased chenodeoxycholate content, which increases the hydrophobicity index of bile acids. This increase may lead to direct toxicity that kills hepatocytes, and promotes inflammation. To address this issue, this study assessed how pathophysiological concentrations of bile acids measured in cholestatic patients affected primary human hepatocytes. Individual bile acid levels were determined in serum and bile by UPLC/QTOFMS in patients with extrahepatic cholestasis with, or without, concurrent increases in serum transaminases. Bile acid levels increased in serum of patients with liver injury, while biliary levels decreased, implicating infarction of the biliary tracts. To assess bile acid-induced toxicity in man, primary human hepatocytes were treated with relevant concentrations, derived from patient data, of the model bile acid glycochenodeoxycholic acid (GCDC). Treatment with GCDC resulted in necrosis with no increase in apoptotic parameters. This was recapitulated by treatment with biliary bile acid concentrations, but not serum concentrations. Marked elevations in serum full-length cytokeratin-18, high mobility group box1 protein (HMGB1), and acetylated HMGB1 confirmed inflammatory necrosis in injured patients; only modest elevations in caspase-cleaved cytokeratin-18 were observed. These data suggest human hepatocytes are more resistant to human-relevant bile acids than rodent hepatocytes, and die through necrosis when exposed to bile acids. These mechanisms of cholestasis in humans are fundamentally different to mechanisms observed in rodent models. PMID:25636263

  9. Bile acid-induced necrosis in primary human hepatocytes and in patients with obstructive cholestasis

    SciTech Connect

    Woolbright, Benjamin L.; Dorko, Kenneth; Antoine, Daniel J.; Clarke, Joanna I.; Gholami, Parviz; Li, Feng; Kumer, Sean C.; Schmitt, Timothy M.; Forster, Jameson; Fan, Fang; Jenkins, Rosalind E.; Park, B. Kevin; Hagenbuch, Bruno; Olyaee, Mojtaba; Jaeschke, Hartmut

    2015-03-15

    Accumulation of bile acids is a major mediator of cholestatic liver injury. Recent studies indicate bile acid composition between humans and rodents is dramatically different, as humans have a higher percent of glycine conjugated bile acids and increased chenodeoxycholate content, which increases the hydrophobicity index of bile acids. This increase may lead to direct toxicity that kills hepatocytes, and promotes inflammation. To address this issue, this study assessed how pathophysiological concentrations of bile acids measured in cholestatic patients affected primary human hepatocytes. Individual bile acid levels were determined in serum and bile by UPLC/QTOFMS in patients with extrahepatic cholestasis with, or without, concurrent increases in serum transaminases. Bile acid levels increased in serum of patients with liver injury, while biliary levels decreased, implicating infarction of the biliary tracts. To assess bile acid-induced toxicity in man, primary human hepatocytes were treated with relevant concentrations, derived from patient data, of the model bile acid glycochenodeoxycholic acid (GCDC). Treatment with GCDC resulted in necrosis with no increase in apoptotic parameters. This was recapitulated by treatment with biliary bile acid concentrations, but not serum concentrations. Marked elevations in serum full-length cytokeratin-18, high mobility group box 1 protein (HMGB1), and acetylated HMGB1 confirmed inflammatory necrosis in injured patients; only modest elevations in caspase-cleaved cytokeratin-18 were observed. These data suggest human hepatocytes are more resistant to human-relevant bile acids than rodent hepatocytes, and die through necrosis when exposed to bile acids. These mechanisms of cholestasis in humans are fundamentally different to mechanisms observed in rodent models. - Highlights: • Cholestatic liver injury is due to cytoplasmic bile acid accumulation in hepatocytes. • Primary human hepatocytes are resistant to BA-induced injury compared to rodents. • Primary human hepatocytes largely undergo necrosis in response to BA toxicity. • Cholestatic liver injury in vivo is predominantly necrotic with minor apoptosis. • Rodent models of bile acid toxicity may not recapitulate the injury in man.

  10. Helicobacter pylori impedes acid-induced tightening of gastric epithelial junctions

    PubMed Central

    Marcus, Elizabeth A.; Vagin, Olga; Tokhtaeva, Elmira; Sachs, George

    2013-01-01

    Gastric infection by Helicobacter pylori is the most common cause of ulcer disease and gastric cancer. The mechanism of progression from gastritis and inflammation to ulcers and cancer in a fraction of those infected is not definitively known. Significant acidity is unique to the gastric environment and is required for ulcer development. The interplay between gastric acidity and H. pylori pathogenesis is important in progression to advanced disease. The aim of this study was to characterize the impact of acid on gastric epithelial integrity and cytokine release and how H. pylori infection alters these responses. Human gastric epithelial (HGE-20) cells were grown on porous inserts, and survival, barrier function, and cytokine release were studied at various apical pH levels in the presence and absence of H. pylori. With apical acidity, gastric epithelial cells demonstrate increased barrier function, as evidenced by increased transepithelial electrical resistance (TEER) and decreased paracellular permeability. This effect is reduced in the presence of wild-type, but not urease knockout, H. pylori. The epithelial inflammatory response is also modulated by acidity and H. pylori infection. Without H. pylori, epithelial IL-8 release decreases in acid, while IL-6 release increases. In the presence of H. pylori, acidic pH diminishes the magnitude of the previously reported increase in IL-8 and IL-6 release. H. pylori interferes with the gastric epithelial response to acid, contributing to altered barrier function and inflammatory response. H. pylori diminishes acid-induced tightening of cell junctions in a urease-dependent manner, suggesting that local pH elevation promotes barrier compromise and progression to mucosal damage. PMID:23989011

  11. The influence of pretreatment with ghrelin on the development of acetic-acid-induced colitis in rats.

    PubMed

    Maduzia, D; Matuszyk, A; Ceranowicz, D; Warzecha, Z; Ceranowicz, P; Fyderek, K; Galazka, K; Dembinski, A

    2015-12-01

    Ghrelin has been primarily shown to exhibit protective and therapeutic effect in the gut. Pretreatment with ghrelin inhibits the development of acute pancreatitis and accelerates pancreatic recovery in the course of this disease. In the stomach, ghrelin reduces gastric mucosal damage induced by ethanol, stress or alendronate, as well as accelerates the healing of acetic acid-induced gastric and duodenal ulcer. The aim of present studies was to investigate the effect of pretreatment with ghrelin on the development of acetic acid-induced colitis. Studies have been performed on male Wistar rats. Animals were treated intraperitoneally with saline (control) or ghrelin (4, 8 or 16 nmol/kg/dose). Saline or ghrelin was given twice: 8 and 1 h before induction of colitis. Colitis was induced by a rectal enema with 1 ml of 4% solution of acetic acid and the severity of colitis was assessed 1 or 24 hours after induction of inflammation. Rectal administration of acetic acid induced colitis in all animals. Damage of colonic wall was seen at the macroscopic and microscopic level. This effect was accompanied by a reduction in colonic blood flow and mucosal DNA synthesis. Moreover, induction of colitis significantly increased mucosal concentration of pro-inflammatory interleukin-1β (IL-1β), activity of myeloperoxidase and concentration of malondialdehyde (MDA). Mucosal activity of superoxide dismutase (SOD) was reduced. Pretreatment with ghrelin reduced the area and grade of mucosal damage. This effect was accompanied by an improvement of blood flow, DNA synthesis and SOD activity in colonic mucosa. Moreover, ghrelin administration reduced mucosal concentration of IL-1β and MDA, as well as decreased mucosal activity of myeloperoxidase. Administration of ghrelin protects the large bowel against the development of the acetic acid-induced colitis and this effect seems to be related to the ghrelin-evoked anti-inflammatory and anti-oxidative effects. PMID:26769837

  12. Uric acid induces endothelial dysfunction by vascular insulin resistance associated with the impairment of nitric oxide synthesis.

    PubMed

    Choi, You-Jin; Yoon, Yujin; Lee, Kang-Yo; Hien, Tran Thi; Kang, Keon Wook; Kim, Kyong-Cheol; Lee, Jeewoo; Lee, Moo-Yeol; Lee, Seung Mi; Kang, Duk-Hee; Lee, Byung-Hoon

    2014-07-01

    Endothelial dysfunction is defined as impairment of the balance between endothelium-dependent vasodilation and constriction. Despite evidence of uric acid-induced endothelial dysfunction, a relationship with insulin resistance has not been clearly established. In this study, we investigated the role of vascular insulin resistance in uric acid-induced endothelial dysfunction. Uric acid inhibited insulin-induced endothelial nitric oxide synthase (eNOS) phosphorylation and NO production more substantially than endothelin-1 expression in HUVECs, with IC50 of 51.0, 73.6, and 184.2, respectively. Suppression of eNOS phosphorylation and NO production by uric acid was PI3K/Akt-dependent, as verified by the transfection with p110. Treatment of rats with the uricase inhibitor allantoxanamide induced mild hyperuricemia and increased mean arterial pressure by 25%. While hyperuricemic rats did not show systemic insulin resistance, they showed impaired vasorelaxation induced by insulin by 56%. A compromised insulin response in terms of the Akt/eNOS pathway was observed in the aortic ring of hyperuricemic rats. Coadministration with allopurinol reduced serum uric acid levels and blood pressure and restored the effect of insulin on Akt-eNOS pathway and vasorelaxation. Taken together, uric acid induced endothelial dysfunction by contributing to vascular insulin resistance in terms of insulin-induced NO production, potentially leading to the development of hypertension.-Choi, Y.-J., Yoon, Y., Lee, K.-Y., Hien, T. T., Kang, K. W., Kim, K.-C., Lee, J., Lee, M.-Y., Lee, S. M., Kang, D.-H., Lee, B.-H. Uric acid induces endothelial dysfunction by vascular insulin resistance associated with the impairment of nitric oxide synthesis. PMID:24652948

  13. Gestational diabetes mellitus enhances arachidonic and docosahexaenoic acids in placental phospholipids.

    PubMed

    Bitsanis, Demetris; Ghebremeskel, Kebreab; Moodley, Therishnee; Crawford, Michael A; Djahanbakhch, Ovrang

    2006-04-01

    In previous studies, we reported that neonates of women with gestational diabetes mellitus (GDM) have reduced blood levels of arachidonic acid (AA) and docosahexaenoic acid (DHA) that were unrelated to maternal status. Since both AA and DHA are selectively transferred from maternal to fetal circulation by the placenta, we have investigated whether the FA composition of the placenta is altered by GDM. Thirty-six women, 11 with and 25 without GDM, were recruited from Newham General Hospital, London. The women with GDM had higher levels of di-homo-gamma-linolenic (P < 0.05), docosatetraenoic (n-6 DTA; P< 0.0001), docosapentaenoic n-6 (P< 0.005), total n-6 (P < 0.005), docosapentaenoic (n-3 DPA; P < 0.005), and total n-3 (P < 0.01) FA, as well as higher levels of AA (P < 0.05) and DHA (P < 0.01), in placental choline phosphoglycerides (CPG) compared with the healthy women who served as controls. Similarly, the women with GDM had elevated n-6 DTA (P < 0.005), AA, total n-6 metabolites (P < 0.05), DHA, total n-3 metabolites, and total n-3 FA (P < 0.005) in ethanolamine phosphoglycerides (EPG). In contrast to CPG and EPG, the placental TG of the women with GDM had higher linoleic acid (P< 0.05) and lower AA, n-6 metabolites, and n-3 DPA (P < 0.01). The placenta is devoid of desaturase activity, and it is thought to be reliant on maternal circulation for both AA and DHA. Hence, the enhanced levels of the two FA in the placenta of the GDM group suggests that these FA are taken up from the maternal circulation and retained after esterification into phosphoglycerides instead of being transferred to the fetus. Further study is needed to elucidate the mechanism involved and the effect of the phenomenon on postnatal growth and development of the offspring. PMID:16808147

  14. Arachidonic acid pathway activates multidrug resistance related protein in cultured human lung cells.

    PubMed

    Torky, Abdelrahman; Raemisch, Anja; Glahn, Felix; Foth, Heidi

    2008-05-01

    Primary cultures of human lung cells can serve as a model system to study the mechanisms underlying the effects of irritants in air and to get a deeper insight into the (patho)physiological roles of the xenobiotic detoxification systems. For 99 human lung cancer cases the culture duration for bronchial epithelium and peripheral lung cells (PLC) are given in term of generations and weeks. Using this system, we investigated whether and how prostaglandins (PG) modify multidrug resistance related protein (MRP) function in normal human lung cells. PGF2alpha had no effect on MRP function, whereas PGE2 induced MRP activity in cultured NHBECs. The transport activity study of MRP in NHBEC, PLC, and A549 under the effect of exogenously supplied PGF2alpha (10 microM, 1 day) using single cell fluorimetry revealed no alteration in transport activity of MRP. PG concentrations were within the physiological range. COX I and II inhibitors indomethacin (5, 10 microM) and celecoxib (5, 10 microM) could substantially decrease the transport activity of MRP in NHBEC, PLC, and A549 in 1- and 4-day trials. Prostaglandin E2 did not change cadmium-induced caspase 3/7 activation in NHBECs and had no own effect on caspase 3/7 activity. Cadmium chloride (5, 10 microM) was an effective inducer of caspase 3/7 activation in NHBECs with a fivefold and ninefold rise of activity. In primary human lung cells arachidonic acid activates MRP transport function only in primary epithelial lung cells by prostaglandin E2 but not by F2alpha mediated pathways and this effect needs some time to develop. PMID:17943274

  15. Inability of murine peritoneal macrophages to convert linoleic acid into arachidonic acid. Evidence of chain elongation

    SciTech Connect

    Chapkin, R.S.; Somers, S.D.; Erickson, K.L.

    1988-04-01

    Various murine macrophage populations synthesize and secrete large amounts of arachidonic acid (20:4n-6) derived eicosanoids (cyclo-oxygenase and lipoxygenase products). These metabolites are known to possess a wide variety of functions with regard to the initiation and regulation of inflammation and tumorigenesis. Because the dietary intake of 20:4n-6 is usually low, tissues are largely dependent upon dietary linoleic acid (18:2n-6) as an initial unsaturated precursor for the biosynthesis of 20:4n-6. The purpose of these experiments was to determine whether resident or responsive murine macrophages possess desaturase and elongase activities capable of in vitro conversion of 18:2n-6 into 20:4n-6. Peritoneal exudate macrophages were purified by adherence and incubated in serum-free medium containing fatty acid-free BSA with (1-14C) 18:2n-6. Approximately 90 to 98% of the (14C)18:2n-6 at 4 and 16 h was recovered in phosphatidylcholine and phosphatidylethanolamine. The metabolism of (14C)18:2n-6 was determined after transesterification and separation of the 14C-fatty acid methyl esters by argentation TLC, reverse phase HPLC, and electron impact gas chromatography/mass spectrometry. Resident and responsive macrophages lacked the capacity to transform (14C)18:2n-6 into 20:4n-6. In addition, prelabeled macrophages incubated with soluble, calcium ionophore A23187 or phorbol myristate, or particulate, zymosan, membrane perturbing agents also lacked delta 6 desaturase activity. All macrophages tested were capable of elongating (14C)18:2n-6 into (14C)20:2n-6. These observations suggest that 20:4n-6, present in macrophage phospholipids, is biosynthesized elsewhere and transported to the macrophage for esterification into the phospholipids. In addition, these findings demonstrate that elongase activity is present in both the resident and responsive peritoneal macrophage.

  16. Arachidonic and oleic acid exert distinct effects on the DNA methylome.

    PubMed

    Silva-Martínez, Guillermo A; Rodríguez-Ríos, Dalia; Alvarado-Caudillo, Yolanda; Vaquero, Alejandro; Esteller, Manel; Carmona, F Javier; Moran, Sebastian; Nielsen, Finn C; Wickström-Lindholm, Marie; Wrobel, Katarzyna; Wrobel, Kazimierz; Barbosa-Sabanero, Gloria; Zaina, Silvio; Lund, Gertrud

    2016-05-01

    Abnormal fatty acid metabolism and availability are landmarks of metabolic diseases, which in turn are associated with aberrant DNA methylation profiles. To understand the role of fatty acids in disease epigenetics, we sought DNA methylation profiles specifically induced by arachidonic (AA) or oleic acid (OA) in cultured cells and compared those with published profiles of normal and diseased tissues. THP-1 monocytes were stimulated with AA or OA and analyzed using Infinium HumanMethylation450 BeadChip (Illumina) and Human Exon 1.0 ST array (Affymetrix). Data were corroborated in mouse embryonic fibroblasts. Comparisons with publicly available data were conducted by standard bioinformatics. AA and OA elicited a complex response marked by a general DNA hypermethylation and hypomethylation in the 1-200 μM range, respectively, with a maximal differential response at the 100 μM dose. The divergent response to AA and OA was prominent within the gene body of target genes, where it correlated positively with transcription. AA-induced DNA methylation profiles were similar to the corresponding profiles described for palmitic acid, atherosclerosis, diabetes, obesity, and autism, but relatively dissimilar from OA-induced profiles. Furthermore, human atherosclerosis grade-associated DNA methylation profiles were significantly enriched in AA-induced profiles. Biochemical evidence pointed to β-oxidation, PPAR-α, and sirtuin 1 as important mediators of AA-induced DNA methylation changes. In conclusion, AA and OA exert distinct effects on the DNA methylome. The observation that AA may contribute to shape the epigenome of important metabolic diseases, supports and expands current diet-based therapeutic and preventive efforts. PMID:27088456

  17. Arachidonic acid metabolism in isolated rat aorta. Dependence of prostacyclin biosynthesis on extracellular potassium concentration.

    PubMed

    Düsing, R; Scherhag, R; Tippelmann, R; Budde, U; Glänzer, K; Kramer, H J

    1982-02-25

    Slices of rat aorta were incubated in Krebs-Ringer bicarbonate buffer for measurements of immunoreactive 6-ketoprostaglandin F1 alpha, thromboxane (TX) B2, prostaglandin (PG)E2, and PGF2 alpha, and in Tris buffer (pH 9.3) for determination of prostacyclin (PGI2)-like activity. No significant generation of TXB2, PGE2, or PGF2 alpha by rat aortic tissue could be detected. The time-dependent release of 6-keto-PGF1 alpha Krebs-Ringer bicarbonate buffer closely correlated with PGI2 generation in alkaline Tris buffer. During a 30-min incubation period, 6-keto-PGF1 alpha, release was 79.8 +/- 3.3 pmol/mg at a buffer potassium concentration of 3.9 mmol/liter and significantly increased by 23% to 98.3 +/- 8.5 pmol/mg (P less than 0.025) in the absence of potassium in the incubation medium. A smaller decrease in buffer potassium concentration to 2.1 mmol/liter and an increase to 8.8 mmol/liter did not significantly alter aortic 6-keto-PGF1 alpha release. Changes in the incubation buffer sodium concentration from 144 mmol/liter to either 138 or 150 mmol/liter at a constant potassium concentration of 3.9 mmol/liter did not alter the recovery of 6-keto-PGF1 alpha. Our results support the concept that PGI2 is the predominant product of arachidonic acid metabolism in rat aorta. They further show that PGI2 can be recovered quantitatively as 6-keto-PGF1 alpha under the present in vitro conditions. In addition, this in vitro study points to the potassium ion as a modulator of vascular PGI2 synthesis with a stimulation at low potassium concentrations. PMID:6799518

  18. Arachidonic acid-mediated inhibition of a potassium current in the giant neurons of Aplysia

    SciTech Connect

    Carlson, R.O.

    1990-01-01

    Biochemical and electrophysiological approaches were used to investigate the role of arachidonic acid (AA) in the modulation of an inwardly rectifying potassium current (I{sub R}) in the giant neurons of the marine snail, Aplysia californica. Using ({sup 3}H)AA as tracer, the intracellular free AA pool in Aplysia ganglia was found to be in a state of constant and rapid turnover through deacylation and reacylation of phospholipid, primarily phosphatidyl-inositol. This constant turnover was accompanied by a constant release of free AA and eicosanoids into the extracellular medium. The effects of three pharmacological agents were characterized with regard to AA metabolism in Aplysia ganglia. 4-O-tetra-decanoylphorbol 13-acetate (TPA), an activator of protein kinase C, stimulated liberation of AA from phospholipid, and 4-bromophenacylbromide (BPB), an inhibitor of phospholipate A{sub 2}, inhibited this liberation. Indomethacin at 250 {mu}M was found to inhibit uptake of AA, likely through inhibition of acyl-CoA synthetase. These agents were also found to modulate I{sub R} in ways which were consistent with their biological effects: TPA inhibited I{sub R}, and both BPB and indomethacin stimulated I{sub R} . Modulation of I{sub R} by these substances was found not to involve cAMP metabolism. Acute application of exogenous AA did not affect I{sub R}; however, I{sub R} in giant neurons was found to be inhibited after dialysis with AA or other unsaturated fatty acids. Also, after perfusion with BSA overnight, a treatment which strips the giant neurons of AA in lipid storage, I{sub R} was found to have increased over 2-fold. This perfusion-induced increase was inhibited by the presence of AA or by pretreatment of the giant neurons with BPB. These results suggest AA, provided through constant turnover from phospholipid, mediates constitutive inhibition of I{sub R}.

  19. Mechanism of arachidonic acid liberation in platelet-activating factor-stimulated human polymorphonuclear neutrophils

    SciTech Connect

    Nakashima, S.; Suganuma, A.; Sato, M.; Tohmatsu, T.; Nozawa, Y. )

    1989-08-15

    Upon stimulation of human polymorphonuclear neutrophils with platelet-activating factor (PAF), arachidonic acid (AA) is released from membrane phospholipids. The mechanism for AA liberation, a key step in the synthesis of biologically active eicosanoids, was investigated. PAF was found to elicit an increase in the cytoplasmic level of free Ca2+ as monitored by fluorescent indicator fura 2. When (3H) AA-labeled neutrophils were exposed to PAF, the enhanced release of AA was observed with a concomitant decrease of radioactivity in phosphatidylinositol and phosphatidylcholine fractions. The inhibitors of phospholipase A2, mepacrine and 2-(p-amylcinnamoyl)-amino-4-chlorobenzoic acid, effectively suppressed the liberation of (3H)AA from phospholipids, indicating that liberation of AA is mainly catalyzed by the action of phospholipase A2. The extracellular Ca2+ is not required for AA release. However, intracellular Ca2+ antagonists, TMB-8 and high dose of quin 2/AM drastically reduced the liberation of AA induced by PAF, indicating that Ca2+ is an essential factor for phospholipase A2 activation. PAF raised the fluorescence of fura 2 at concentrations as low as 8 pM which reached a maximal level about 8 nM, whereas more than nM order concentrations of PAF was required for the detectable release of (3H)AA. Pretreatment of neutrophils with pertussis toxin resulted in complete abolition of AA liberation in response to PAF. However, the fura 2 response to PAF was not effectively inhibited by toxin treatment. In human neutrophil homogenate and membrane preparations, guanosine 5'-O-(thiotriphosphate) stimulated AA release and potentiated the action of PAF. Guanosine 5'-O-(thiodiphosphate) inhibited the effects of guanosine 5'-O-(thiotriphosphate).

  20. Increased dietary arachidonic acid enhances the synthesis of vasoactive eicosanoids in humans.

    PubMed

    Ferretti, A; Nelson, G J; Schmidt, P C; Kelley, D S; Bartolini, G; Flanagan, V P

    1997-04-01

    Data on the effect of dietary arachidonic acid (AA) (20:4n-6) on the synthesis of thromboxane and prostacyclin (PGI2) in humans are lacking. We measured the effect of 1.5 g/d (ca. 0.5 en%) of 20:4n-6 added isocalorically to a stabilization (low-AA) diet on the excretion of 11-dehydrothromboxane B2 (11-DTXB2) and 2,3-dinor-6-oxo-PGF1 alpha (PGI2-M). In a crossover design, 10 healthy men, living in a metabolic unit, were fed a diet (low-AA) containing 210 mg/d of 20:4n-6 for 65 d and an identical diet (high-AA) that contained 1.5 g/d of additional 20:4n-6 for 50 d. Three-day urine pools were collected at the end of each dietary period and analyzed for eicosanoids by gas chromatography-electron capture negative ion-tandem mass spectrometry. Mean excretion of 11-dehydrothromboxane B2 was 515 +/- 76, 493 +/- 154, and 696 +/- 144 ng/d (SD; n = 10) during the acclimation (15 d) low-AA diet and high-AA diet periods, respectively (41% increase from low-AA to high-AA diet, P = 0.0037); mean excretion of PGI2-M was 125 +/- 40, 151 +/- 36, and 192 +/- 55 ng/d (SD; n = 10) during acclimation (15 d) low-AA and high-AA diets; P = 0.0143). Thus both the metabolites of thromboxane and PGI2 increase on the high-AA diet. Furthermore, both indicated changes in metabolite excretion may be associated with measurable effects on several physiologically significant cellular functions, such as platelet aggregation in vivo and inflammation in response to immune challenges. PMID:9113633

  1. Bradykinin-stimulated electrolyte secretion in rabbit and guinea pig intestine. Involvement of arachidonic acid metabolites.

    PubMed Central

    Musch, M W; Kachur, J F; Miller, R J; Field, M; Stoff, J S

    1983-01-01

    Bradykinin (BK) increases short-circuit current (Isc) when added to the serosal side of rabbit or guinea pig ileum or rabbit colon. Significant effects on Isc are seen at concentrations as low as 10(-10) M. Anion substitution experiments and unidirectional 36Cl flux measurements indicate that this effect of BK on Isc is due to Cl secretion. The effect of BK on Isc can be partially blocked (60-70% inhibition) by cyclooxygenase inhibitors (indomethacin and/or naproxen) and completely blocked by the phospholipase inhibitor, mepacrine. The combined cyclooxygenase/lipoxygenase inhibitors BW 755 and eicosa-5,8,11,14-tetraynoic acid (ETYA) also completely block the effect of BK on Isc but the slow-reacting substance of anaphylaxis (SRS-A) antagonist FPL 55712 has no effect. None of the above inhibitors diminish the effect on Isc of other exogenously added secretory stimuli such as vasoactive intestinal peptide (VIP), theophylline, or prostaglandin E2 (PGE2). Prior desensitization of rabbit ileum to PGE2 blocks the effect on Isc of BK but not those of VIP or theophylline. Conversely, prior desensitization of rabbit ileum to BK greatly reduces the effect of PGE2 on Isc. BK also stimulates the synthesis of PGE2 in rabbit ileal and colonic mucosa and this effect can be blocked by prior addition of either indomethacin or mepacrine. These effects of BK are similar to those of exogenously added arachidonic acid (AA). AA also stimulates Cl secretion and increases PGE2 synthesis and its effect on Isc can be inhibited by prior desensitization to PGE2 or by prior addition of indomethacin. The above results indicate that BK stimulates active Cl secretion in both small and large intestine and suggest that this effect is due to the intracellular release of AA. Although the prostaglandins appear to be the major products of AA metabolism contributing to the secretory response, lipoxygenase products may also play a role. PMID:6406543

  2. Arachidonic acid metabolism by bovine placental tissue during the last month of pregnancy

    SciTech Connect

    Hoedemaker, M.; Weston, P.G.; Wagner, W.C. )

    1991-01-01

    Conversion of tritiated arachidonic acid (AA) into metabolites of the cyclo- and lipoxygenase pathways by bovine fetal placental tissue (200 mg) and fetal plus maternal placental tissue (400 mg) of Days 255, 265, 275 of gestation and at parturition (n = 5) during a 30 min incubation was measured using reverse-phase high pressure liquid chromatography. Fetal placental tissue produced 13,14-dihydro-15-keto-prostaglandin E2 (PGEM) as the major metabolite, the synthesis of which increased from Day 265 to Day 275 and parturition by 150% and 475%, respectively. In tissues collected at parturition, PGE2 synthesis was also detected. On Day 275 and at parturition fetal placental tissue synthesized the metabolite 12-hydroxyheptadecatrienoic acid (HHT), and throughout the experimental period the lipoxygenase product 15-HETE was detected with synthesis rates increasing over time of gestation. In addition, an unidentified metabolite was regularly found in the radiochromatograms which eluted at 1 h and 1 min (U101), between HHT and 15-HETE. The synthesis of this metabolite decreased as pregnancy progressed. Furthermore, various other polar and nonpolar metabolites pooled under the heading UNID were eluted, the production of which increased over time of gestation. The presence of maternal placental tissue did not influence the synthesis of PGEM, 15-HETE and U101, but the production of HHT was decreased when maternal tissue was present. Also, as pregnancy progressed, maternal placental tissue seemed to contribute to the pool of unidentified metabolites. In conclusion, fetal placental tissue seems to be the major source of the AA metabolites when compared with maternal placental tissue, and AA metabolism by bovine placental tissue is markedly increased throughout the last month of pregnancy, suggesting a role for AA metabolites in mechanisms controlling parturition.

  3. Positive cooperativity between the thrombin and bradykinin B2 receptors enhances arachidonic acid release

    PubMed Central

    Hecquet, Claudie; Biyashev, Dauren; Tan, Fulong; Erdös, Ervin G.

    2006-01-01

    Bradykinin (BK) or kallikreins activate B2 receptors (R) which couple Gαi and Gαq proteins to release arachidonic acid (AA) and elevate [Ca2+]i. Thrombin cleaves the protease-activated-receptor-1 (PAR1) that couples Gαi, Gαq and Gα12/13 proteins. In CHO cells stably transfected with human B2R, thrombin liberated little AA, but it significantly potentiated AA release by B2R agonists. We explored mechanisms of cooperativity between constitutively expressed PAR1 and B2R. We also examined human endothelial cells expressing both Rs constitutively. The PAR1 agonist hexapeptide (TRAP) was as effective as thrombin. Inhibitors of components of Gαi, Gαq and Gα12/13 signaling pathways, and a PKCα inhibitor, Gö6976 blocked potentiation while phorbol, an activator, enhanced it. Several inhibitors, including a RhoA kinase inhibitor, a [Ca2+]i antagonist, and an inositol-(1,3,4)-trisphosphate R antagonist, reduced mobilization of [Ca2+]i by thrombin and blocked potentiation of AA release by B2R agonists. Because either a non-selective inhibitor (isotetrandrine) of phospholipase A2 (PLA2) or a Ca2+-dependent PLA2 inhibitor abolished potentiation of AA release by thrombin, while a Ca2+-independent PLA2 inhibitor did not, we concluded that the mechanism involves Ca2+-dependent PLA2 activation. Both thrombin and TRAP modified activation and phosphorylation of the B2R induced by BK. In lower concentrations they enhanced it, while higher concentrations inhibited phosphorylation and diminished B2R activation. Protection of the N-terminal Ser1-Phe2 bond of TRAP by an aminopeptidase inhibitor made this peptide much more active than the unprotected agonist. Thus, PAR1 activation enhances AA release by B2R agonists through signal transduction pathway. PMID:16183725

  4. Production of arachidonic and eicosapentaenoic acids by the marine oomycete Halophytophthora.

    PubMed

    Pang, Ka-Lai; Lin, Han-Jia; Lin, Hung-Yun; Huang, Yu-Fen; Chen, Yi-Min

    2015-04-01

    Polyunsaturated fatty acids (PUFAs) are fatty acids with more than one double bond in the chemical structure. Arachidonic acid (ARA, 20:4 (n-6)) and eicosapentaenoic acid (EPA, 22:5 (n-3)) are common PUFAs with beneficial health effects. Marine fish and meat are the main sources of omega-3 and omega-6 fatty acids in human's diet, respectively. In particular, there is a general decline in fish catch, implicating the need for an alternative source of omega-3 fatty acids. Previous studies have examined the production of polyunsaturated fatty acids including ARA and EPA by various microorganisms, including microalgae, fungi, and thraustochytrids. In this study, the production of ARA and EPA by 10 isolates of four estuarine Halophytophthora species (Halophytophthora avicenniae, Halophytophthora polymorphica, Halophytophthora vesicula, and Halophytophthora spinosa var. spinosa) cultured from fallen mangrove leaves in Taiwan was examined. The yield of ARA ranged from 0.004 to 0.052 g/L with the highest yield of ARA obtained from H. spinosa var. spinosa IMB162, but no or a very low level of EPA was produced by IMB162. For EPA production by Halophytophthora spp., the yield ranged from 0 to 0.047 g/L. Percentage of ARA in total fatty acid ranged between 7.16 and 25.02%. One-way ANOVA analysis using Tukey Test (p ≥ 0.05) suggested that there is significant difference in the percentage of EPA in total fatty acid produced by the isolates, which ranged from 0.01 to 18.42%. BODIPY 505/515 fluorescent staining suggests that lipid bodies were evenly distributed in the mycelia of Halophytophthora species. PMID:25119161

  5. Chemical nature and immunotoxicological properties of arachidonic acid degradation products formed by exposure to ozone

    SciTech Connect

    Madden, M.C.; Friedman, M.; Hanley, N.; Siegler, E.; Quay, J.; Becker, S.; Devlin, R.; Koren, H.S. )

    1993-06-01

    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 responses to this toxicant. To study the chemical nature and biological activity of O3-exposed AA, we exposed AA in a cell-free, aqueous environment to air, 0.1 ppm O3, or 1.0 ppm O3 for 30-120 min. AA exposed to air was not degraded. All O3 exposures degraded > 98% of the AA to more polar products, which were predominantly aldehydic substances (as determined by reactivity with 2,4-dinitrophenylhydrazine and subsequent separation by HPLC) and hydrogen peroxide. The type and amount of aldehydic substances formed depended on the O3 concentration and exposure duration. A human bronchial epithelial cell line (BEAS-2B, S6 subclone) exposed in vitro to either 0.1 ppm or 1.0 ppm O3 for 1 hr produced AA-derived aldehydic substances, some of which eluted with similar retention times as the aldehydic substances derived from O3 degradation of AA in the cell-free system. In vitro, O3-degraded AA induced an increase in human peripheral blood polymorphonuclear leukocyte (PMN) polarization, decreased human peripheral blood T-lymphocyte proliferation in response to mitogens, and decreased human peripheral blood natural killer cell lysis of K562 target cells. The aldehydic substances, but not hydrogen peroxide, appeared to be the principal active agents responsible for the observed effects. O3-degraded AA may play a role in the PMN influx into lungs and in decreased T-lymphocyte mitogenesis and natural killer cell activity observed in humans and rodents exposed to O3.

  6. Effects of sexually dimorphic growth hormone secretory patterns on arachidonic acid metabolizing enzymes in rodent heart.

    PubMed

    Zhang, Furong; Yu, Xuming; He, Chunyan; Ouyang, Xiufang; Wu, Jinhua; Li, Jie; Zhang, Junjie; Duan, Xuejiao; Wan, Yu; Yue, Jiang

    2015-12-15

    The arachidonic acid (AA) metabolizing enzymes are the potential therapeutic targets of cardiovascular diseases (CVDs). As sex differences have been shown in the risk and outcome of CVDs, we investigated the regulation of heart AA metabolizing enzymes (COXs, LOXs, and CYPs) by sex-dependent growth hormone (GH) secretory patterns. The pulsatile (masculine) GH secretion at a physiological concentration decreased CYP1A1 and CYP2J3 mRNA levels more efficiently in the H9c2 cells compared with the constant (feminine) GH secretion; however, CYP1B1 mRNA levels were higher following the pulsatile GH secretion. Sex differences in CYP1A1, CYP1B1, and CYP2J11 mRNA levels were observed in both the wild-type and GHR deficient mice. No sex differences in the mRNA levels of COXs, LOXs, or CYP2E1 were observed in the wild-type mice. The constant GH infusion induced heart CYP1A1 and CYP2J11, and decreased CYP1B1 in the male C57/B6 mice constantly infused with GH (0.4 μg/h, 7 days). The activity of rat Cyp2j3 promoter was inhibited by the STAT5B protein, but was activated by C/EBPα (CEBPA). Compared with the constant GH administration, the levels of the nuclear phosphorylated STAT5B protein and its binding to the rat Cyp2j3 promoter were higher following the pulsatile GH administration. The constant GH infusion decreased the binding of the nuclear phosphorylated STAT5B protein to the mouse Cyp2j11 promoter. The data suggest the sexually dimorphic transcription of heart AA metabolizing enzymes, which might alter the risk and outcome of CVDs. GHR-STAT5B signal transduction pathway may be involved in the sex difference in heart CYP2J levels. PMID:26493931

  7. Positive cooperativity between the thrombin and bradykinin B2 receptors enhances arachidonic acid release.

    PubMed

    Hecquet, Claudie; Biyashev, Dauren; Tan, Fulong; Erdös, Ervin G

    2006-03-01

    Bradykinin (BK) or kallikreins activate B2 receptors (R) that couple Galpha(i) and Galpha(q) proteins to release arachidonic acid (AA) and elevate intracellular Ca2+ concentration ([Ca2+]i). Thrombin cleaves the protease-activated-receptor-1 (PAR1) that couples Galpha(i), Galpha(q), and Galpha(12/13) proteins. In Chinese hamster ovary cells stably transfected with human B2R, thrombin liberated little AA, but it significantly potentiated AA release by B2R agonists. We explored mechanisms of cooperativity between constitutively expressed PAR1 and B2R. We also examined human endothelial cells expressing both Rs constitutively. The PAR1 agonist hexapeptide (TRAP) was as effective as thrombin. Inhibitors of components of Galpha(i), Galpha(q), and Galpha(12/13) signaling pathways, and a protein kinase C (PKC)-alpha inhibitor, Gö-6976, blocked potentiation, while phorbol, an activator, enhanced it. Several inhibitors, including a RhoA kinase inhibitor, a [Ca2+]i antagonist, and an inositol-(1,3,4)-trisphosphate R antagonist, reduced mobilization of [Ca2+]i by thrombin and blocked potentiation of AA release by B2R agonists. Because either a nonselective inhibitor (isotetrandrine) of phospholipase A2 (PLA2) or a Ca2+-dependent PLA2 inhibitor abolished potentiation of AA release by thrombin, while a Ca2+-independent PLA2 inhibitor did not, we concluded that the mechanism involves Ca2+-dependent PLA2 activation. Both thrombin and TRAP modified activation and phosphorylation of the B2R induced by BK. In lower concentrations they enhanced it, while higher concentrations inhibited phosphorylation and diminished B2R activation. Protection of the NH2-terminal Ser1-Phe2 bond of TRAP by an aminopeptidase inhibitor made this peptide much more active than the unprotected agonist. Thus PAR1 activation enhances AA release by B2R agonists through signal transduction pathway. PMID:16183725

  8. Delta-6-desaturase activity and arachidonic acid synthesis are increased in human breast cancer tissue.

    PubMed

    Pender-Cudlip, Marilla C; Krag, Karen J; Martini, David; Yu, Jeanne; Guidi, Anthony; Skinner, Sandy S; Zhang, Yu; Qu, Xiying; He, Chengwei; Xu, Yi; Qian, Steven Y; Kang, Jing X

    2013-06-01

    Omega-6 (n-6) arachidonic acid (AA) and its pro-inflammatory metabolites, including prostaglandin E2 (PGE(2)), are known to promote tumorigenesis. Delta-6 desaturase (D6D) is the rate-limiting enzyme for converting n-6 linoleic acid (LA) to AA. Our objective was to determine if AA synthesis, specifically D6D activity, and PGE(2) levels are increased in cancerous breast tissue, and whether these variables differ between estrogen receptor positive (ER+) and negative (ER-) breast cancers. Gas chromatography was performed on surgical breast tissue samples collected from 69 women with breast cancer. Fifty-four had ER+ breast cancer, and 15 had ER- breast cancer. Liquid chromatography-mass spectrometry was used to determine PGE(2) levels. Lipid analysis revealed higher levels of LA metabolites (C18:3 n-6, C20:3 n-6, and AA) in cancerous tissue than in adjacent noncancerous tissue (P < 0.01). The ratio of LA metabolites to LA, a measure of D6D activity, was increased in cancerous tissue, suggesting greater conversion of LA to AA (P < 0.001), and was higher in ER- than in ER+ patients, indicating genotype-related trends. Similarly, PGE(2) levels were increased in cancerous tissue, particularly in ER- patients. The results showed that the endogenous AA synthetic pathway, D6D activity, and PGE(2) levels are increased in breast tumors, particularly those of the ER- genotype. These findings suggest that the AA synthetic pathway and the D6D enzyme in particular may be involved in the pathogenesis of breast cancer. The development of drugs and nutritional interventions to alter this pathway may provide new strategies for breast cancer prevention and treatment. PMID:23414387

  9. Repurposing Resveratrol and Fluconazole To Modulate Human Cytochrome P450-Mediated Arachidonic Acid Metabolism.

    PubMed

    El-Sherbeni, Ahmed A; El-Kadi, Ayman O S

    2016-04-01

    Cytochrome P450 (P450) enzymes metabolize arachidonic acid (AA) to several biologically active epoxyeicosatrienoic acids (EETs) and hydroxyeicosatetraenoic acids (HETEs). Repurposing clinically-approved drugs could provide safe and readily available means to control EETs and HETEs levels in humans. Our aim was to determine how to significantly and selectively modulate P450-AA metabolism in humans by clinically-approved drugs. Liquid chromatography-mass spectrometry was used to determine the formation of 15 AA metabolites by human recombinant P450 enzymes, as well as human liver and kidney microsomes. CYP2C19 showed the highest EET-forming activity, while CYP1B1 and CYP2C8 showed the highest midchain HETE-forming activities. CYP1A1 and CYP4 showed the highest subterminal- and 20-HETE-forming activity, respectively. Resveratrol and fluconazole produced the most selective and significant modulation of hepatic P450-AA metabolism, comparable to investigational agents. Monte Carlo simulations showed that 90% of human population would experience a decrease by 6-22%, 16-39%, and 16-35% in 16-, 18-, and 20-HETE formation, respectively, after 2.5 g daily of resveratrol, and by 22-31% and 14-23% in 8,9- and 14,15-EET formation after 50 mg of fluconazole. In conclusion, clinically-approved drugs can provide selective and effective means to modulate P450-AA metabolism, comparable to investigational drugs. Resveratrol and fluconazole are good candidates to be repurposed as new P450-based treatments. PMID:26918316

  10. Recombinant cytochrome P450 2D18 metabolism of dopamine and arachidonic acid.

    PubMed

    Thompson, C M; Capdevila, J H; Strobel, H W

    2000-09-01

    The function of cytochrome P450 (P450) in the mammalian brain is not well understood. In an effort to further this understanding, this study identifies two endogenous substrates for P450 2D18. Previous reports have shown that this isoform is expressed in the rat brain, and the recombinant enzyme catalyzes the N-demethylation of the antidepressants imipramine and desipramine. By further examining the substrate profile of P450 2D18, inferences can be made as to potential endogenous P450 substrates. Herein we demonstrate the metabolism of the central nervous system-acting compounds chlorpromazine and chlorzoxazone with turnover numbers of 1.8 and 0. 9 nmol/min/nmol, respectively. Because the four aforementioned pharmaceutical substrates work by binding to neurotransmitter receptors, binding assays and oxidation reactions were performed to test whether dopamine is a substrate for P450 2D18. These data indicate a K(S) value of 678 microM and that P450 2D18 can support the oxidation of dopamine to aminochrome through a peroxide-shunt mechanism. We also report the P450 2D18-mediated omega-hydroxylation and epoxygenation of arachidonic acid, primarily leading to the formation of 8,9-, 11,12-, and 14,15-epoxyeicosatrienoic acids, compounds that have been shown to have vasoactive properties in brain, kidney, and heart tissues. The data presented herein suggest a possible role for P450 involvement in membrane and receptor regulation via epoxyeicosatrienoic acid formation and a potential involvement of P450 in the oxidation of dopamine to reactive oxygen species under aberrant physiological conditions where the sequestering of dopamine becomes compromised, such as in Parkinson's disease. PMID:10945868

  11. Arachidonic acid needed in infant formula when docosahexaenoic acid is present.

    PubMed

    Brenna, J Thomas

    2016-05-01

    Recently, the European Food Safety Authority asserted that arachidonic acid (ARA) is an optional nutrient for the term infant even when docosahexaenoic acid (DHA) is present. The brief rationale is based on an explicit, widespread misapplication of the concept of "essential fatty acids" to linoleic acid that implies it is uniquely required as a nutrient per se. Linoleic acid prevents acute clinical symptoms caused by polyunsaturated fatty acid-deficient diets and is the major precursor for ARA in most human diets. Experimental diets with ARA as the sole n-6 similarly prevent symptoms but at a lower energy percentage than linoleic acid and show ARA is a precursor for linoleic acid. The absence of consistent evidence of ARA benefit from randomized controlled trials is apparently an issue as well. This review highlights basic and clinical research relevant to ARA requirements as an adjunct to DHA in infancy. ARA is a major structural central nervous system component, where it rapidly accumulates perinatally and is required for signaling. Tracer studies show that ARA-fed infants derive about half of their total body ARA from dietary preformed ARA. Clinically, of the 3 cohorts of term infants studied with designs isolating the effects of ARA (DHA-only vs DHA+ARA), none considered ARA-specific outcomes such as vascular or immune function; the study with the highest ARA level showed significant neurocognitive benefit. All breastfed term infants of adequately nourished mothers consume both DHA and ARA. The burden of proof to substantially deviate from the composition of breastmilk is greater than that available from inherently empirical human randomized controlled trial evidence. Infant formulas with DHA but without ARA risk harm from suppression of ARA-mediated metabolism manifest among the many unstudied functions of ARA. PMID:27013482

  12. Extracts from Tribulus species may modulate platelet adhesion by interfering with arachidonic acid metabolism.

    PubMed

    Olas, Beata; Hamed, Arafa I; Oleszek, Wieslaw; Stochmal, Anna

    2015-01-01

    The present work was designed to study the effects of crude extracts from Tribulus pterocarpus, T. pentandrus and T. parvispinus on selected biological functions of human blood platelets in vitro. Platelet suspensions were pre-incubated with extracts from aerial parts of T. pterocarpus, T. pentandrus and T. parvispinus, at the final concentrations of 0.5, 5 and 50 µg/ml. Then, for platelet activation thrombin, was used. The effects of crude extracts from T. pterocarpus, T. pentandrus and T. parvispinus on adhesion of blood platelets to collagen were determined by method according to Tuszynski and Murphy. Arachidonic acid metabolism was measured by the level of thiobarbituric acid reactive substances (TBARS). In these studies we also compared the action of tested crude plant extracts with the effects of the polyphenolic fraction isolated from aerial parts of T. pterocarpus, which has antiplatelet and antioxidative properties. The performed assays demonstrated that the tested crude extract from T. pterocarpus and the phenolic fraction from T. pterocarpus might influence the platelet functions in vitro. The inhibitory, concentration-dependent effects of this tested extract and its phenolic fraction on adhesion of resting platelets and thrombin - stimulated platelets to collagen was found. We also observed that the crude extract from T. pterocarpus, like the polyphenolic fraction from T. pterocarpus reduced TBARS production in blood platelets. In the comparative studies, the tested crude extract from T. pterocarpus was not found to be more effective antiplatelet factor, than the polyphenolic fraction from this plant. The results obtained suggest that T. pterocarpus may be a promising source of natural compounds, valuable in the prevention of the enhanced activity of blood platelets in numerous cardiovascular diseases. PMID:24512189

  13. Effect of Arachidonic Acid-enriched Oil Diet Supplementation on the Taste of Broiler Meat

    PubMed Central

    Takahashi, H.; Rikimaru, K.; Kiyohara, R.; Yamaguchi, S.

    2012-01-01

    To elucidate the relationship between the arachidonic acid (AA) content and the taste of broiler meat, the effects of AA-enriched oil (AAO) supplements on the fatty acid content and sensory perceptions of thigh meat were evaluated. Four types of oil, including corn oil (CO), a 1:1 mixture of AAO and palm oil (PO) (1/2 AAO), a 1:3 mixture of AAO and PO (1/4 AAO), and a 1:7 mixture of AAO and PO (1/8 AAO) were prepared. Each type of oil was mixed with silicate at a ratio of 7:3, and added to the diet at a final proportion of 5% of fresh matter. Broiler chickens were fed these diets for 1 wk before slaughter. In thigh meat, the AA content of the 1/2 and 1/4 AAO groups was significantly higher than that of the CO group. The AA content in thigh meat (y, mg/g) increased linearly with increasing dietary AAO content (x, g/100 g of diet), according to the equation y = 0.5674+0.4596× (r2 = 0.8454). The content of other fatty acids was not significantly different among the 4 diet groups. Sensory evaluation showed that the flavor intensity, umami (L-glutamate taste), kokumi (continuity, mouthfulness, and thickness), and aftertaste of the 1/2 and 1/4 AAO groups were significantly higher than that of the CO group. There were significant positive correlations between AA content in thigh meat and the flavor intensity, total taste intensity, umami, and aftertaste. These data suggest that the taste of broiler meat can be improved by the amount of dietary AA supplementation. PMID:25049636

  14. Arachidonic acid-derived signaling lipids and functions in impaired healing

    PubMed Central

    Dhall, Sandeep; Wijesinghe, Dayanjan Shanaka; Karim, Zubair A.; Castro, Anthony; Vemana, Hari Priya; Khasawneh, Fadi T.; Chalfant, Charles E.; Martins-Green, Manuela

    2016-01-01

    Very little is known about lipid function during wound healing, and much less during impaired healing. Such understanding will help identify what roles lipid signaling plays in the development of impaired/chronic wounds. We took a lipidomics approach to study the alterations in lipid profile in the LIGHT−/− mouse model of impaired healing which has characteristics that resemble those of impaired/chronic wounds in humans, including high levels of oxidative stress, excess inflammation, increased extracellular matrix degradation and blood vessels with fibrin cuffs. The latter suggests excess coagulation and potentially increased platelet aggregation. We show here that in these impaired wounds there is an imbalance in the arachidonic acid (AA) derived eicosonoids that mediate or modulate inflammatory reactions and platelet aggregation. In the LIGHT−/− impaired wounds there is a significant increase in enzymatically derived breakdown products of AA. We found that early after injury there was a significant increase in the eicosanoids 11-, 12-, and 15-hydroxyeicosa-tetranoic acid, and the proinflammatory leukotrienes (LTD4 and LTE) and prostaglandins (PGE2 and PGF2α). Some of these eicosanoids also promote platelet aggregation. This led us to examine the levels of other eicosanoids known to be involved in the latter process. We found that thromboxane (TXA2/B2), and prostacyclins 6kPGF1α are elevated shortly after wounding and in some cases during healing. To determine whether they have an impact in platelet aggregation and hemostasis, we tested LIGHT−/− mouse wounds for these two parameters and found that, indeed, platelet aggregation and hemostasis are enhanced in these mice when compared with the control C57BL/6 mice. Understanding lipid signaling in impaired wounds can potentially lead to development of new therapeutics or in using existing nonsteroidal anti-inflammatory agents to help correct the course of healing. PMID:26135854

  15. Enhancement of arachidonic acid signaling pathway by nicotinic acid receptor HM74A

    SciTech Connect

    Tang, Yuting . E-mail: ytang@prdus.jnj.com; Zhou, Lubing; Gunnet, Joseph W.; Wines, Pamela G.; Cryan, Ellen V.; Demarest, Keith T.

    2006-06-23

    HM74A is a G protein-coupled receptor for nicotinic acid (niacin), which has been used clinically to treat dyslipidemia for decades. The molecular mechanisms whereby niacin exerts its pleiotropic effects on lipid metabolism remain largely unknown. In addition, the most common side effect in niacin therapy is skin flushing that is caused by prostaglandin release, suggesting that the phospholipase A{sub 2} (PLA{sub 2})/arachidonic acid (AA) pathway is involved. Various eicosanoids have been shown to activate peroxisome-proliferator activated receptors (PPAR) that play a diverse array of roles in lipid metabolism. To further elucidate the potential roles of HM74A in mediating the therapeutic effects and/or side effects of niacin, we sought to explore the signaling events upon HM74A activation. Here we demonstrated that HM74A synergistically enhanced UTP- and bradykinin-mediated AA release in a pertussis toxin-sensitive manner in A431 cells. Activation of HM74A also led to Ca{sup 2+}-mobilization and enhanced bradykinin-promoted Ca{sup 2+}-mobilization through Gi protein. While HM74A increased ERK1/2 activation by the bradykinin receptor, it had no effects on UTP-promoted ERK1/2 activation.Furthermore, UTP- and bradykinin-mediated AA release was significantly decreased in the presence of both MAPK kinase inhibitor PD 098059 and PKC inhibitor GF 109203X. However, the synergistic effects of HM74A were not dramatically affected by co-treatment with both inhibitors, indicating the cross-talk occurred at the receptor level. Finally, stimulation of A431 cells transiently transfected with PPRE-luciferase with AA significantly induced luciferase activity, mimicking the effects of PPAR{gamma} agonist rosiglitazone, suggesting that alteration of AA signaling pathway can regulate gene expression via endogenous PPARs.

  16. Chemical nature and immunotoxicological properties of arachidonic acid degradation products formed by exposure to ozone.

    PubMed Central

    Madden, M C; Friedman, M; Hanley, N; Siegler, E; Quay, J; Becker, S; Devlin, R; Koren, H S

    1993-01-01

    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 responses to this toxicant. To study the chemical nature and biological activity of O3-exposed AA, we exposed AA in a cell-free, aqueous environment to air, 0.1 ppm O3, or 1.0 ppm O3 for 30-120 min. AA exposed to air was not degraded. All O3 exposures degraded > 98% of the AA to more polar products, which were predominantly aldehydic substances (as determined by reactivity with 2,4-dinitrophenylhydrazine and subsequent separation by HPLC) and hydrogen peroxide. The type and amount of aldehydic substances formed depended on the O3 concentration and exposure duration. A human bronchial epithelial cell line (BEAS-2B, S6 subclone) exposed in vitro to either 0.1 ppm or 1.0 ppm O3 for 1 hr produced AA-derived aldehydic substances, some of which eluted with similar retention times as the aldehydic substances derived from O3 degradation of AA in the cell-free system. In vitro, O3-degraded AA induced an increase in human peripheral blood polymorphonuclear leukocyte (PMN) polarization, decreased human peripheral blood T-lymphocyte proliferation in response to mitogens, and decreased human peripheral blood natural killer cell lysis of K562 target cells. The aldehydic substances, but not hydrogen peroxide, appeared to be the principal active agents responsible for the observed effects. O3-degraded AA may play a role in the PMN influx into lungs and in decreased T-lymphocyte mitogenesis and natural killer cell activity observed in humans and rodents exposed to O3. PMID:8354202

  17. Reciprocal Regulation of TREK-1 Channels by Arachidonic Acid and CRH in Mouse Corticotropes

    PubMed Central

    Lee, Andy K.; Smart, James L.; Rubinstein, Marcelo; Low, Malcolm J.

    2011-01-01

    Arachidonic acid (AA) is generated in the anterior pituitary gland upon stimulation by the ACTH secretagogue, CRH. Using the patch clamp technique, we examined the action of AA on the excitability of single pituitary corticotropes obtained from a transgenic mouse strain that expresses the enhanced green fluorescent protein driven by the proopiomelanocortin promoter. CRH evoked depolarization, but AA caused hyperpolarization. Under voltage clamp condition, AA caused a rapid inhibition of the delayed rectifier K+ current and then increased a background K+ current. Inhibition of AA metabolism did not prevent the activation of the K+ current by AA, suggesting a direct action of AA. The sensitivity of the AA-activated K+ current to fluoxetine, chlorpromazine, extracellular acidification, diphenylbutylpiperidine antipsychotics, and the membrane permeable cAMP analog [8-(4-chlorophenylthio)-cAMP] suggest that the current is mediated via TWIK-related K+ channel (TREK)-1 channels. Activation of the CRH receptors that are coupled to the adenylate cyclase pathway suppressed the activation of TREK-1 current by AA and reversed the AA-mediated hyperpolarization. Intracellular acidification (pH 7.0) increased the basal amplitude of TREK-1 current and resulted in hyperpolarizaton. CRH suppressed the basal TREK-1 current in cells with intracellular acidification and caused depolarization. Our finding indicates that TREK-1 channels are important in setting the resting potential in corticotropes. The opposing actions of CRH and AA on the excitability of corticotropes raise the possibility that AA may act as a negative feedback regulator to reduce the stimulatory action of CRH and thus prevent excessive ACTH release during chronic stress. PMID:21343252

  18. Effect of Arachidonic Acid-enriched Oil Diet Supplementation on the Taste of Broiler Meat.

    PubMed

    Takahashi, H; Rikimaru, K; Kiyohara, R; Yamaguchi, S

    2012-06-01

    To elucidate the relationship between the arachidonic acid (AA) content and the taste of broiler meat, the effects of AA-enriched oil (AAO) supplements on the fatty acid content and sensory perceptions of thigh meat were evaluated. Four types of oil, including corn oil (CO), a 1:1 mixture of AAO and palm oil (PO) (1/2 AAO), a 1:3 mixture of AAO and PO (1/4 AAO), and a 1:7 mixture of AAO and PO (1/8 AAO) were prepared. Each type of oil was mixed with silicate at a ratio of 7:3, and added to the diet at a final proportion of 5% of fresh matter. Broiler chickens were fed these diets for 1 wk before slaughter. In thigh meat, the AA content of the 1/2 and 1/4 AAO groups was significantly higher than that of the CO group. The AA content in thigh meat (y, mg/g) increased linearly with increasing dietary AAO content (x, g/100 g of diet), according to the equation y = 0.5674+0.4596 (r(2) = 0.8454). The content of other fatty acids was not significantly different among the 4 diet groups. Sensory evaluation showed that the flavor intensity, umami (L-glutamate taste), kokumi (continuity, mouthfulness, and thickness), and aftertaste of the 1/2 and 1/4 AAO groups were significantly higher than that of the CO group. There were significant positive correlations between AA content in thigh meat and the flavor intensity, total taste intensity, umami, and aftertaste. These data suggest that the taste of broiler meat can be improved by the amount of dietary AA supplementation. PMID:25049636

  19. Arachidonic acid-derived signaling lipids and functions in impaired healing.

    PubMed

    Dhall, Sandeep; Wijesinghe, Dayanjan Shanaka; Karim, Zubair A; Castro, Anthony; Vemana, Hari Priya; Khasawneh, Fadi T; Chalfant, Charles E; Martins-Green, Manuela

    2015-09-01

    Very little is known about lipid function during wound healing, and much less during impaired healing. Such understanding will help identify what roles lipid signaling plays in the development of impaired/chronic wounds. We took a lipidomics approach to study the alterations in lipid profile in the LIGHT(-/-) mouse model of impaired healing which has characteristics that resemble those of impaired/chronic wounds in humans, including high levels of oxidative stress, excess inflammation, increased extracellular matrix degradation and blood vessels with fibrin cuffs. The latter suggests excess coagulation and potentially increased platelet aggregation. We show here that in these impaired wounds there is an imbalance in the arachidonic acid (AA) derived eicosonoids that mediate or modulate inflammatory reactions and platelet aggregation. In the LIGHT(-/-) impaired wounds there is a significant increase in enzymatically derived breakdown products of AA. We found that early after injury there was a significant increase in the eicosanoids 11-, 12-, and 15-hydroxyeicosa-tetranoic acid, and the proinflammatory leukotrienes (LTD4 and LTE) and prostaglandins (PGE2 and PGF2α ). Some of these eicosanoids also promote platelet aggregation. This led us to examine the levels of other eicosanoids known to be involved in the latter process. We found that thromboxane (TXA2 /B2 ), and prostacyclins 6kPGF1α are elevated shortly after wounding and in some cases during healing. To determine whether they have an impact in platelet aggregation and hemostasis, we tested LIGHT(-/-) mouse wounds for these two parameters and found that, indeed, platelet aggregation and hemostasis are enhanced in these mice when compared with the control C57BL/6 mice. Understanding lipid signaling in impaired wounds can potentially lead to development of new therapeutics or in using existing nonsteroidal anti-inflammatory agents to help correct the course of healing. PMID:26135854

  20. Effects of arachidonic acid upon the volume-sensitive chloride current in rat osteoblast-like (ROS 17/2.8) cells.

    PubMed Central

    Gosling, M; Poyner, D R; Smith, J W

    1996-01-01

    1. The effects of arachidonic acid upon the volume-sensitive Cl- current present in cultured osteoblastic cells (ROS 17/2.8) was studied using the whole-cell patch-clamp technique. 2. Arachidonate produced two distinct phases of inhibition, a rapid phase occurring within 10-15 s of application, preceding a slower phase that occurred 2 min after onset of arachidonate superfusion. Accompanying the slower inhibitory phase was an acceleration of the time-dependent inactivation exhibited by the current at strongly depolarized potentials (> + 50 mV). The half-maximal inhibitory concentrations (IC50) were 177 +/- 31 and 10 +/- 4 microM for the two phases, respectively. 3. Arachidonate was still effective in the presence of inhibitors of cyclo-oxygenase (indomethacin, 10 microM), lipoxygenase (nordihydroguaretic acid, 10-100 microM) and cytochrome P450 (SKF525A, 100 microM; ethoxyresorufin, 10 microM; metyrapone, 500 microM; piperonyl butoxide, 500 microM; cimetidine, 1 mM). The effects of arachidonate could not be produced by another cis unsaturated fatty acid, oleic acid. 4. Measurements of cell volume showed that arachidonate effectively inhibited the regulatory volume decrease elicited by ROS 17/2.8 cells in response to a reduction in extracellular osmolarity. 5. It is concluded that the volume-sensitive Cl- conductance in ROS 17/2.8 cells is directly modulated by arachidonate and may represent a physiological mechanism by which volume regulation can be controlled in these cells. PMID:8799885