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1

Effect of Desmodium adscendens fractions on antigen- and arachidonic acid-induced contractions of guinea pig airways.  

PubMed

Three fractions (n-butanol, F2, and L5), isolated from an aqueous extract of Desmodium adscendens, a plant used in Ghana for the management of asthma, were evaluated for their pharmacological activity using ovalbumin and arachidonic acid-induced contractions of guinea pig airways. All three fractions inhibited the ovalbumin-induced contractions of indomethacin-pretreated tracheal spirals from sensitized animals dose dependently, but only L5 and n-butanol inhibited such contractions in the absence of indomethacin. The concentrations required to inhibit ovalbumin-induced contractions of lung parenchymal strips were threefold higher than with trachea. The contractile response over a 60-min period was divided into three phases. F2 and n-butanol inhibited all phases, whereas L5 inhibited only the late phase. n-Butanol and L5 inhibited arachidonic acid-induced contractions on indomethacin-pretreated tracheal spirals, a leukotriene-dependent reaction. There was no inhibition of arachidonic acid-induced contractions of lung parenchymal strips, which is largely a thromboxane-dependent reaction. The results suggest that D. adscendens contains several pharmacologically active substances that can inhibit allergic airway smooth muscle contraction at multiple sites, including the synthesis and (or) activity of the bronchoconstrictor leukotrienes. PMID:3139272

Addy, M E; Burka, J F

1988-06-01

2

trans-Arachidonic acids induce a heme oxygenase-dependent vasorelaxation of cerebral microvasculature.  

PubMed

Nitrative stress is an important regulator of vascular tone. We have recently described that trans-arachidonic acids (TAA) are major products of NO(2)(.)-mediated isomerization of arachidonic acid in cell membranes and that nitrative stress increases TAA levels leading to neural microvascular degeneration. In the present study, we explored whether TAA exert acute effects on neuromicrovascular tone and investigated potential mechanisms thereof. TAA induced an endothelium-dependent vasorelaxation of rat brain pial microvasculature. This vasorelaxation was independent of nitric oxide, prostanoids, lipoxygenase products, and CYP(450) metabolite trans-hydroxyeicosatetraenoic acids. However, inhibition of heme oxygenase (using zinc protoporphyrin IX) and of dependent soluble guanylate cyclase (sGC; using ODQ) significantly diminished (by approximately 70%) the TAA-induced vasorelaxation. Consistent with these findings, TAA stimulated heme oxygenase (HO)-2-dependent bilirubin (using siRNA HO-2) and cGMP formation, and the HO product carbon monoxide (using CO-releasing CORM-2) reproduced the sGC-dependent cGMP formation and vasorelaxation. Further exploration revealed that TAA-induced vasorelaxation and bilirubin formation (HO activation) were nearly abrogated by large-conductance calcium-dependent potassium channels (BK(Ca)) (using TEA and iberiotoxin). Opening of BK(Ca) with the selective activator NS1619 induced a concentration-dependent vasorelaxation, which was inhibited by HO and sGC inhibitors. Coimmunoprecipitation suggested a molecular complex interaction between BK(Ca) and HO-2 (but not HO-1). Collectively, these findings identify new properties of TAA, specifically cerebral vasorelaxation through interactive activation of BK(Ca) with HO-2 and, in turn, sGC. Our findings provide new insights into the characterization of nitrative stress-derived TAA products, by showing they can act as acute mediators of nitrative stress on neurovascular tone. PMID:18082639

Kooli, Amna; Kermorvant-Duchemin, Elsa; Sennlaub, Florian; Bossolasco, Michela; Hou, Xin; Honoré, Jean-Claude; Dennery, Phyllis A; Sapieha, Przemyslaw; Varma, Daya; Lachapelle, Pierre; Zhu, Tang; Tremblay, Sophie; Hardy, Pierre; Jain, Kavita; Balazy, Michael; Chemtob, Sylvain

2008-03-01

3

INCREASED ARACHIDONIC ACID-INDUCED THROMBOXANE GENERATION IMPAIRS SKELETAL MUSCLE ARTERIOLAR DILATION WITH GENETIC DYSLIPIDEMIA  

PubMed Central

Objective To determine if arachidonic acid (AA)-induced skeletal muscle arteriolar dilation is altered with hypercholesterolemia in ApoE and LDLR gene deletion mice fed normal diet. This study also determined contributors to altered AA-induced dilation between dyslipidemic mice and controls; C57/Bl/6J (C57). Methods Gracilis muscle arterioles were isolated, with mechanical responses assessed following challenge with AA under control conditions and after elements of AA metabolism pathways were inhibited. Conduit arteries from each strain were used to assess AA-induced production of PGI2 and TxA2. Results Arterioles from ApoE and LDLR exhibited a blunted dilation to AA versus C57. While responses were cyclooxygenase-dependent in all strains, inhibition of thromboxane synthase or blockade of PGH2/TxA2 receptors improved dilation in ApoE and LDLR only. AA-induced generation of PGI2 was comparable across strains, although TxA2 generation was increased in ApoE and LDLR. Arteriolar reactivity to PGI2 and TxA2 was comparable across strains. Treatment with TEMPOL improved dilation and reduced TxA2 production with AA in ApoE and LDLR. Conclusions These results suggest that AA-induced arteriolar dilation is constrained in ApoE and LDLR via an increased production of TxA2. While partially due to elevated oxidant stress, additional mechanisms contribute which are independent of acute alterations in oxidant tone. PMID:18720229

Goodwill, Adam. G.; Stapleton, Phoebe A.; James, Milinda E.; d’Audiffret, Alexandre C.; Frisbee, Jefferson C.

2011-01-01

4

[Arachidonic acid-induced aggregation of human peripheral blood neutrophils in the presence of interceptors of active forms of oxygen].  

PubMed

Arachidonate-induced aggregation of human peripheral blood neutrophils and the influence of certain interreceptors of oxygen active forms (OAF) on its rate were studied. The results obtained have shown that OAF play an important role in the processes of interaction between arachidonate and leucocytes. Regulation of the process of leucocyte aggregation may be realized during arachidonate-induced aggregation of neutrophils, due to interaction of cell-generated OAF with arachidonic acid and its lipoxygenase metabolites. PMID:2168332

Zorin, V P; Pogirnitskaia, A V; Cherenkevich, S N

1990-05-01

5

Arachidonic acid induces ERK activation via Src SH2 domain association with the epidermal growth factor receptor  

Microsoft Academic Search

Within the kidney, angiotensin II type 2 (AT2) receptor mediates phospholipase A2 (PLA2) activation, arachidonic acid release, epidermal growth factor (EGF) receptor transactivation, and mitogen-activated protein kinase activation. Arachidonic acid mimics this transactivation by an undetermined mechanism. The role of c-Src in mediating angiotensin II and arachidonic acid signaling was determined by employing immunocomplex kinase assay, Western blotting analysis, and

L D Alexander; Y Ding; S Alagarsamy; X-L Cui; J G Douglas

2006-01-01

6

Arachidonic acid-induced H+ and Ca2+ increases in both the cytoplasm and nucleoplasm of rat cerebellar granule cells  

PubMed Central

Arachidonic acid (AA) exerts multiple physiological and pathophysiological effects in the brain. By continuously measuring the intracellular pH (pHi) and Ca2+ levels ([Ca2+]i) in primary cultured rat cerebellar granule cells, we have found, for the first time, that 20 min treatment with 10 ?m AA resulted in marked increases in Ca2+ and H+ levels in both the cytosol and nucleus. A much higher concentration (40 mm) of another weak acid, propionic acid, was needed to induce a similar change in pHi. The [Ca2+]i increase was probably caused by AA-induced activation of Ni2+-sensitive cationic channels, but did not involve NMDA channels or the Na+-Ca2+ exchanger. AA-induced acidosis occurs by a different mechanism involving predominantly the passive diffusion of the un-ionized form of AA, rather than a protein carrier, as proposed by Kamp & Hamilton for fatty acids (FAs) in artificial phospholipid bilayers (the ‘flip-flop’ model). The following results, which are similar to those observed in lipid bilayers, support this conclusion: (1) FAs containing a -COOH group (AA, linoleic acid, ?-linolenic acid, and docosahexaenoic acid) induced intracellular acidosis, whereas a FA with a -COOCH3 group (AA methyl ester) had little effect on pHi, (2) a FA amine, tetradecylamine, induced intracellular alkalosis, and (3) the AA-/FA-induced pHi changes were reversed by bovine serum albumin. Further evidence in support of a passive diffusion model, rather than a membrane protein carrier, is that: (1) there was a linear relationship between the initial rate of acid flux and the concentration of AA (2-100 ?m), (2) acidosis was not inhibited by 4,4?-diisothiocyanatostilbene-2,2?-disulphonic acid, a potent inhibitor of the plasma membrane FA carrier protein, and (3) the involvement of most known H+-related membrane carriers and H+ conductance has been ruled out. Since AA can be released under both physiological and pathophysiological conditions, the possible significance of the AA-evoked increases in H+ and Ca2+ in both the cytoplasm and nucleoplasm is discussed. PMID:11731581

Chen, Wei-Hao; Chen, Chia-Rong; Yang, Kun-Ta; Chang, Wei-Luen; Su, Ming-Ja; Wu, Chau-Chung; Wu, Mei-Lin

2001-01-01

7

Contribution of K+ channels to arachidonic acid-induced endothelium-dependent vasodilation in rat isolated perfused mesenteric arteries.  

PubMed

The contribution of K+ channels and cytochrome P450 generated arachidonic acid (AA) metabolites to the endothelium-dependent vasodilation produced by this fatty acid in the perfused rat isolated mesenteric arteries was examined using a variety of compounds known to inhibit transmembrane K+ channels and cytochrome P450 enzymes. AA (1-1000 nmol) caused dose- and endothelium-dependent vasodilation in the presence of indomethacin and the effect was neither altered by lipoxygenase (AA 861) nor cytochrome P450 monooxygenase (alpha-naphthoflavone, ketoconazole and metyrapone) inhibitors indicating that AA-induced, endothelium-dependent vasodilation in this vascular bed was not mediated by product(s) of AA metabolism. The vasodilator effect of AA was also not altered by L-NG-nitro-arginine, methylene blue (50 microM), oxyhemoglobin (5 microM) or superoxide dismutase (50 U/ml), thus ruling out nitric oxide being its mediator. Conversely, arterial perfusion with K(+)-free or excess (50 mM) K+ Krebs' solution, but not ouabain infusion, minimized the vasodilator effect of AA, suggesting that this action of the fatty acid is due to changes in membrane K+ conductance that is independent of Na+/K(+)-adenosine triphosphatase activity. The vasodilator action of BRL 34915 (a K+ channel activator) was also minimized by extracellular K+ depletion or excess K+ (50 mM), but not by ouabain. Apamin (0.5 microM) and crude scorpion venom (2.5 micrograms/ml) attenuated AA- but not BRL 34915-induced vasodilation. Glyburide (inhibitor of ATP-activated K+ channel) abolished the vasodilator action of AA and BRL 34915. Procaine, a nonspecific K+ channel blocker did not affect AA-induced vasodilation even though it attenuated that caused by BRL 34915.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1650826

Adeagbo, A S; Malik, K U

1991-08-01

8

Arachidonic Acid Induces Production of 17,20?-Dihydroxy-4-pregnen-3-one (DHP) via a Putative PGE2 Receptor in Fish Follicles from the Eurasian Perch  

Microsoft Academic Search

The effects of docosahexaenoic, eicosaenoic and arachidonic acids (DHA, EPA and ARA, respectively) on sex-steroid and prostaglandin\\u000a (PG) production were investigated in Eurasian perch (Perca fluviatilis) follicles using an in- vitro incubation technique. Only ARA was able to induce the production of 17,20?-dihydroxy-4-pregnen-3-one\\u000a (DHP), the hormone produced by vitellogenic follicles undergoing final meiotic maturation, as well as the production of

E. Henrotte; S. Milla; S. N. M. Mandiki; P. Kestemont

2011-01-01

9

Electroacupuncture at ST36-ST37 and at Ear Ameliorates Hippocampal Mossy Fiber Sprouting in Kainic Acid-Induced Epileptic Seizure Rats  

PubMed Central

Our previous study showed that mossy fiber sprouting can occur in the hippocampus region in rats 6?wk after kainic acid-induced epileptic seizure, and this mossy fiber sprouting can facilitate epileptogenesis. Transcutaneous auricular vagal nerve stimulation (VNS), which is similar to cervical VNS, can reduce the occurrence of epileptic seizure in intractable epilepsy patients. Greater parasympathetic nerve activity can be caused by 2?Hz electroacupuncture (EA). Therefore, we investigated the effect of 2?Hz EA at ST-36-ST37 and at the ear on mossy fiber sprouting in kainic-treated Sprague-Dawley rats. The results indicated that applying 2?Hz EA at ST36-ST37 and at the ear for 3?d per week over 6 consecutive weeks can ameliorate mossy fiber sprouting in the hippocampus region of rats. These results indicated that applying 2?Hz EA at ST36-ST37 and at the ear might be beneficial for the treatment and prevention of epilepsy in humans. PMID:25045697

Lin, Yi-Wen; Liu, Hsu-Jan; Lin, Wan-Jung

2014-01-01

10

Antiinflammatory activity of flavonoids: Mouse ear edema inhibition  

Microsoft Academic Search

In this investigation, the various flavonoid aglycones were evaluated for their inhibitory activities against croton-oil or\\u000a arachidonic acid induced mouse ear edema by oral or topical administration. The compounds tested were thirteen derivatives\\u000a of flavan-3-ol (catechin and epicatechin), flavanone (flavanone and naringenin), flavone (flavone, chrysin and apigenin),\\u000a flavonol (flavonol, galangin, quercetin and morin) and isoflavone (biochanin A and 2-carbethoxy5,7-dihydroxy-4?-methoxyisoflavone),\\u000a along

Hee Kee Kim; Soon Young Namgoong; Hyun Pyo Kim

1993-01-01

11

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

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

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

2015-01-01

12

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

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

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

2015-01-01

13

Renal vascular responsiveness to arachidonic acid in experimental diabetes.  

PubMed Central

1. Isolated perfused kidneys from diabetic rats (duration 4-6 and 20-24 weeks) were more sensitive to the vasoconstrictor effects of arachidonic acid than kidneys from age-matched control rats. Sensitivity diminished with age in both control and diabetic groups. 2. The enhanced vasoconstrictor effect of arachidonic acid in diabetic rat kidneys was associated with increased conversion to prostaglandins. 3. The renal vasoconstrictor response to arachidonic acid in both groups was reduced by thromboxane A2/prostaglandin H2 receptor antagonism but not by inhibition of thromboxane synthase. 4. Diabetic rat kidneys were also more sensitive to the vasoconstrictor effects of the endoperoxide analogue, U46619, while vasoconstrictor responses to phenylephrine were not markedly different from those of control rat kidneys. 5. In conclusion, prostaglandin endoperoxides appear to mediate arachidonic acid-induced vasoconstriction in diabetic and control rat kidneys. The enhanced renal vasoconstrictor response to arachidonic acid in diabetic rats results from increased sensitivity to endoperoxides and increased formation of endoperoxides from arachidonic acid. PMID:2116203

Quilley, J.; McGiff, J. C.

1990-01-01

14

Ear Infections  

MedlinePLUS

... your doctor. Complications Will earaches hurt my child's hearing? Middle ear infections and fluid in the ear are the ... Leave ear wax alone. If you think your ear wax affects your hearing, see your doctor to be sure there's no ...

15

Ear Problems  

MedlinePLUS

... ear dry while it's healing. Putting a warm heating pad over your ear may help relieve the pain. You can prevent swimmer's ear by placing 3 to 5 ... medicine for a few days. Putting a warm heating pad on your ear may help relieve the pain. ... bite down? Yes A tooth problem can radiate pain to the ear on the same ...

16

Ear Disorders  

MedlinePLUS

... most common illness in infants and young children. Tinnitus, a roaring in your ears, can be the ... problems in your inner ear; its symptoms include tinnitus and dizziness. Ear barotrauma is an injury to ...

17

Ear Pieces  

ERIC Educational Resources Information Center

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…

DiJulio, Betsy

2011-01-01

18

Ear wax  

MedlinePLUS

... water to drain. You may need to repeat irrigation several times. To avoid damaging your ear or ... who may remove the wax by: Repeating the irrigation attempts Suctioning the ear canal Using a small ...

19

Elephant ear  

MedlinePLUS

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

20

Ear Tubes  

MedlinePLUS

... In most cases, this causes no problem with hearing. ?Infection? Ear infections can still occur in the middle ear ... infections are usually less frequent, result in less hearing loss, and are easier to treat?often only with ear drops. Sometimes an oral antibiotic is still needed. ? ...

21

Cauliflower Ear  

MedlinePLUS

... Works Main Page The Pink Locker Society What's Cauliflower Ear? KidsHealth > Kids > Q&A > Q & A > What's Cauliflower Ear? Print A A A Text Size Have ... looks bumpy and lumpy? The person might have cauliflower ear. That sure is a funny name. Let's ...

22

Ear Injuries (For Parents)  

MedlinePLUS

... minor any signs of problems with balance or hearing severe ear pain blood or fluid draining from the ear ( ... My Ears? Taking Care of Your Ears Quiz: Ears Hearing Aids Perforated Eardrum Earbuds Swimmer's Ear (External Otitis) ...

23

Regulation of the functional activity of the human dopamine transporter by the arachidonic acid pathway.  

PubMed

The role of arachidonic acid was examined in the regulation of dopamine transport in C6 glioma cells stably expressing the human dopamine transporter. Exogenously added arachidonic acid (20-160 microM) stimulated [3H]dopamine uptake when pre-incubated for short times (15-30 min); 160 microM arachidonic acid inhibited following longer pre-exposures (45-60 min). Under the same conditions, only decreases were observed in the binding of the cocaine analog [3H]2 beta-carbomethoxy-3 beta-(4-fluorophenyl)tropane ([3H]WIN 35,428). The reduction in dopamine transporter activity by arachidonic acid (at 160 microM for 60 min) was caused by a decrease in the Vmax (from 202 to 44 pmol/mg/min) opposed by a smaller reduction in K(m) (from 1.2 to 0.8 microM), whereas the effect of arachidonic acid (at 160 microM for 15 min) on [3H]WIN 35,428 binding was caused by a reduction in the Bmax (from 1.8 to 1.3 pmol/mg) without a change in Kd (7.2 nM). Upon 15-min exposure, melittin, an activator of phospholipase A2, and nordihydroguaiaretic acid, a lipooxygenase inhibitor, both expected to cause enhanced endogenous arachidonic acid, inhibited [3H]dopamine uptake and [3H]WIN 35,428 binding with an IC50 value close to 1 microM, whereas thimerosal, which raises arachidonic acid by inhibiting lipid reacylation, caused similar reductions at the sub-millimolar level. Co-presence of stauroporine (0.3-2 microM), an inhibitor of protein kinase C, had little or no effect on the melittin- or arachidonic acid-induced inhibition of [3H]dopamine uptake. Both the melittin- and arachidonic acid-, but not phorbol 12-myristate 13-acetate-induced inhibition of uptake were counteracted by bovine serum albumin (0.1 and 1 mg/ml) which binds arachidonic acid. The data taken together suggest that the inhibitory effects of arachidonic acid activators and those of protein kinase C activators on dopamine uptake are mediated by separate mechanisms. PMID:8982675

Zhang, L; Reith, M E

1996-11-21

24

Boswellic acids stimulate arachidonic acid release and 12-lipoxygenase activity in human platelets independent of Ca2+ and differentially interact with platelet-type 12-lipoxygenase.  

PubMed

Boswellic acids inhibit the transformation of arachidonic acid to leukotrienes via 5-lipoxygenase but can also enhance the liberation of arachidonic acid in human leukocytes and platelets. Using human platelets, we explored the molecular mechanisms underlying the boswellic acid-induced release of arachidonic acid and the subsequent metabolism by platelet-type 12-li-poxygenase (p12-LO). Both beta-boswellic acid and 3-O-acetyl-11-keto-boswellic acid (AKBA) markedly enhanced the release of arachidonic acid via cytosolic phospholipase A2 (cPLA2), whereas for generation of 12-hydro(pero)xyeicosatetraenoic acid [12-H(P)ETE], AKBA was less potent than beta-boswellic acid and was without effect at higher concentrations (> or =30 microM). In contrast to thrombin, beta-boswellic acid-induced release of ara-chidonic acid and formation of 12-H(P)ETE was more rapid and occurred in the absence of Ca2+. The Ca2+-independent release of arachidonic acid and 12-H(P)ETE production elicited by beta-boswellic acid was not affected by pharmacological inhibitors of signaling molecules relevant for agonist-induced arachidonic acid liberation and metabolism. It is noteworthy that in cell-free assays, beta-boswellic acid increased p12-LO catalysis approximately 2-fold in the absence but not in the presence of Ca2+, whereas AKBA inhibited p12-LO activity. No direct modulatory effects of boswellic acids on cPLA2 activity in cell-free assays were evident. Therefore, immobilized KBA (linked to Sepharose beads) selectively precipitated p12-LO from platelet lysates but failed to bind cPLA2. Taken together, we show that boswellic acids induce the release of arachidonic acid and the synthesis of 12-H(P)ETE in human platelets by unique Ca2+-independent routes, and we identified p12-LO as a selective molecular target of boswellic acids. PMID:16788089

Poeckel, Daniel; Tausch, Lars; Kather, Nicole; Jauch, Johann; Werz, Oliver

2006-09-01

25

Animal Ears  

NSDL National Science Digital Library

This activity (page 2 of the PDF) is a full inquiry investigation into animal behavior and communication. Groups of learners will fashion a headband with fake ears, similar in shape to those of the animal they are going to observe. Then, they record observations of the animal’s reactions when a learner, wearing the ears in different positions, brings it a snack. Learners develop categories of behavior to organize and evaluate the results. Safety Note: an adult handler must be present if working with a horse or even a large dog. Relates to linked video, DragonflyTV: Horse Ears.

Twin Cities Public Television, Inc.

2006-01-01

26

Pierced Ears  

MedlinePLUS

... run the risk of getting infected ears. Continue Metal Matters Your first earrings should have gold posts ( ... infection and swelling. Later, you may find some metals cause an allergic reaction. You're probably wondering ...

27

Right Ear/Left Ear  

NSDL National Science Digital Library

In this activity (4th on the page), learners conduct a series of tests to find out which of their ears is more dominant. In other words, do they prefer to use their right or left ear to complete tasks? Learners work in pairs and observe each other doing simple tasks like listening to a whisper, listening to a mystery object in a box, and listening through a wall. Learners collect data to draw conclusions about their partner's "earedness."

2012-06-26

28

Arachidonate metabolism in renal injury.  

PubMed

In conclusion, the evidence to date demonstrates that the enhanced arachidonate metabolism seen in hydronephrosis is responsible for the pathophysiological alterations observed in this model of renal injury. The balance between vasodilating prostaglandins and the vasoconstrictor thromboxane A2 may be critical in determining blood flow to the obstructed kidney. The alterations in arachidonate metabolism in this pathophysiologic state appear to result from the invasion of macrophages and the proliferation of fibroblasts in the cortical interstitium. Additionally, the macrophage appears to be necessary for the expression of the enhanced hormone-stimulated arachidonate metabolism. We envision the temporal sequence of events in this model to be as follows: ureter obstruction causes a mechanical disruption and/or immunologic stimulus in the cortex, which triggers a regional inflammatory response resulting in the proliferation of interstitial cells and the invasion of mononuclear cells. The macrophages, which are in direct contact with fibroblasts, are capable of releasing a factor that stimulates fibroblast proliferation, cortical microsomal cyclooxygenase activity, and prostaglandin E2 release (i.e., intrinsic arachidonate metabolism). The enhanced thromboxane synthetase levels and thromboxane A2 appear to come from the macrophage. The prostaglandin E2 and thromboxane A2 released modulate vascular tone. Prostaglandin E2 may also serve as an inhibitor of macrophage function. Two other models of renal damage also exhibit marked enhancement of renal prostaglandin synthesis and induction of thromboxane production: renal venous occlusion (32) and glycerol-induced acute renal failure (3). The finding that several models of renal damage have definite quantitative and qualitative alterations in the prostaglandin cascade reflects the importance of this pathway in renal pathophysiology. PMID:3159195

Lefkowith, J B; Needleman, P

1985-01-01

29

How the Ear Works  

MedlinePLUS

... or policy questions to our media and public relations staff at newsroom@entnet.org . The ear has three main parts: the outer ear (including the external auditory canal), middle ear, and inner ear. The ...

30

Ear Cells  

NSDL National Science Digital Library

Spindly cells in the inner ear, called "hair" cells, are critical for both hearing and balance. Now, in a boon for research, neuro-scientists Jeffrey Corwin and Zhenqing Hu at the University of Virginia School of Medicine have finally grown and multiplied these cells in the lab.

Science Update (AAAS; )

2008-05-06

31

Ear Infections in Children  

MedlinePLUS

Home Health Info Hearing, Ear Infections, and Deafness Ear Infections in Children Ear Infections in Children On this page: What is an ear infection? ... fight new infections and also can affect their hearing. Top How can I tell if my child has an ear infection? Most ear infections happen to children before ...

32

Ear Training  

NSDL National Science Digital Library

Using these websites, you can practice your ear training skills. There are links for intervals, chords, and short melodic segments. First, you should go to this website to practice intervals. Intervals Begin with the first option (simple intervals up). After mastering this, move to simple intervals down. As you become more advanced, continue down the line of interval options. They will become more difficult as you ...

2009-09-15

33

Ear Plastic Surgery  

MedlinePLUS

Ear Plastic Surgery Ear Plastic Surgery Patient Health Information News media interested in covering the latest from AAO-HNS/F can ... weight earrings. Does Insurance Pay for Cosmetic Ear Surgery? Insurance usually does not cover surgery solely for ...

34

Understanding the Ear  

MedlinePLUS

... this page, go to Types and Causes of Hearing Loss . Outer Ear: The outside of the ear, plus the ear ... which is the pathway of sound from the ear to the brain. Back to Hearing Loss Information Back to Info to Go home ...

35

Autoimmune Inner Ear Disease  

MedlinePLUS

... percent of the 28 million Americans with a hearing loss. How Does the Healthy Ear Work? The ear has three main parts: the ... of AIED The symptoms of AIED are sudden hearing loss in one ear progressing rapidly to the second ear. The hearing ...

36

Anti-edema effects of brown seaweed (Undaria pinnatifida) extract on phorbol 12-myristate 13-acetate-induced mouse ear inflammation.  

PubMed

The brown seaweed Undaria pinnatifida (Harvey) Suringar is used in traditional medicine to treat fever, urination problems, lumps and swelling, and as a dietary supplement for post-childbirth women. We examined the anti-inflammatory activities of the seaweed. The methanol extract of the seaweed was active against mouse ear edema induced by phorbol myristate acetate (PMA), with an IC(50) of 10.3 mg/ml. The extract reduced the edema to a half-maximal level when applied at the concentration of 40 mg/ml within 3 hours before or 2 hours after application of PMA. Extract taken from the blade section of the seaweed demonstrated the highest activity. The Northern form of U. pinnatifida was more active than the Southern form. In the analgesic test, the methanol extract suppressed the acetic acid-induced writhing response, with an IC(50) of 0.48 g/kg body weight. The extract also demonstrated antipyretic activity in yeast-induced hyperthermic mice. Activity-related constituents were arachidonic, eicosapentaenoic, and stearidonic acids. PMID:19507279

Khan, Mohammed Nurul Absar; Yoon, Seung-Je; Choi, Jae-Suk; Park, Nam Gyu; Lee, Hyung-Ho; Cho, Ji-Young; Hong, Yong-Ki

2009-01-01

37

Arachidonate metabolism in bovine gallbladder muscle  

SciTech Connect

Incubation of (1-/sup 14/C)arachidonic acid (AA) with homogenates of bovine gallbladder muscle generated a large amount of radioactive material having the chromatographic mobility of 6-keto-PGF1 alpha (stable product of PGI2) and smaller amounts of products that comigrated with PGF2 alpha PGE2. Formation of these products was inhibited by the cyclooxygenase inhibitor indomethacin. The major radioactive product identified by thin-layer chromatographic mobility and by gas chromatography - mass spectrometric analysis was found to be 6-keto-PGF1 alpha. The quantitative metabolic pattern of (1-/sup 14/C)PGH2 was virtually identical to that of (1-/sup 14/C)AA. Incubation of arachidonic acid with slices of bovine gallbladder muscle released labile anti-aggregatory material in the medium, which was inhibited by aspirin or 15-hydroperoxy-AA. These results indicate that bovine gallbladder muscle has a considerable enzymatic capacity to produce PGI2 from arachidonic acid.

Nakano, M.; Hidaka, T.; Ueta, T.; Ogura, R.

1983-04-01

38

Normal Ear, Ear with Hearing Loss, and Cochlear Implant Procedure  

MedlinePLUS

... Implant Surgery Recalls and Safety Animation: Normal Ear, Ear with Hearing Loss, and Cochlear Implant Procedure This is a ... outer ear to the auditory nerve because of hearing loss. In this ear there are fewer nerve impulses in the auditory ...

39

Ear infection - acute  

MedlinePLUS

... there is no improvement or symptoms get worse, schedule an appointment with your health care provider to determine whether antibiotics are needed. ANTIBIOTICS A virus or bacteria can cause ear ... Removing tonsils does not seem to help with ear infections.

40

Mefenamic Acid Induced Nephrotoxicity: An Animal Model  

PubMed Central

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

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

2014-01-01

41

Role of Lipoxygenase Metabolites of Arachidonic Acid in Enhanced Pulmonary Artery Contractions of Female Rabbits  

PubMed Central

Pulmonary arterial hypertension is characterized by elevated pulmonary artery pressure and vascular resistance. In women the incidence is 4 fold greater than that in men. Studies suggest sustained vasoconstriction is a factor in increased vascular resistance. Possible vasoconstrictor mediators include arachidonic acid-derived lipoxygenase metabolites. Our studies in rabbits showed enhanced endothelium-dependent contractions to arachidonic acid in pulmonary arteries from females compared to males. Because treatment with a non-specific lipoxygenase inhibitor reduced contractions in females but not males, the present study identified which lipoxygenase isoform contributes to sex-specific pulmonary artery vasoconstriction. 15- and 5- but not 12-lipoxygenase protein expression was greater in females. Basal and A23187-stimulated release of 15-, 5- and 12-hydroxyeicosatetraenoic acid from females and males was measured by liquid chromatography/mass spectrometry. Only 15-hydroxyeicosatetraenoic acid synthesis was greater in females compared to males under both basal and stimulated conditions. Vascular contractions to 15-hydroxyeicosatetraenoic acid were enhanced in females compared to males (maximal contraction; 44 ± 6% vs 25 ± 3%). The specific 15-lipoxygenase inhibitor PD146176 (12 ?mol/L) decreased arachidonic acid-induced contractions in females (maximal contraction; 93 ± 4% vs 57 ± 10%). If male pulmonary arteries were incubated with estrogen (1 ?mol/L, 18 hrs), protein expression of 15-lipoxygenase, and 15-hydroxyeicosatetraenoic acid production increased. Mechanisms to explain the increased incidence of pulmonary hypertension in women are not known. Results suggest the 15-lipoxygenase pathway is different between females and males and is regulated by estrogen. Understanding this novel sex-specific mechanism may provide insight into the increased incidence of pulmonary hypertension in females. PMID:21300669

Pfister, Sandra L.

2011-01-01

42

?-Hydroxybutyric Acid-Induced Electrographic Seizures  

PubMed Central

We describe a case of absence-like electrographic seizures during NREM sleep in a patient who was taking sodium oxybate, a sodium salt of ?-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. ?-hydroxybutyric acid-induced electrographic seizures. J Clin Sleep Med 2014;10(7):811-812. PMID:25024661

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

2014-01-01

43

Middle Ear Infections and Ear Tube Surgery (For Parents)  

MedlinePLUS

... KidsHealth > Parents > Diseases & Conditions > Ears, Nose, Throat/Speech & Hearing > Middle Ear Infections and Ear Tube Surgery Print A A ... What Happens in the Operating Room? Swimmer's Ear Hearing Impairment Swimmer's Ear (External Otitis) Contact Us Print Additional resources Send ...

44

Pathology of the Ear  

PubMed Central

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

Orengo, Ida; Robbins, Kerri; Marsch, Amanda

2011-01-01

45

Control of arachidonic acid release in chick muscle cultures  

NASA Technical Reports Server (NTRS)

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.

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

1985-01-01

46

Hearing, Ear Infections, and Deafness  

MedlinePLUS

... Health Info Hearing, Ear Infections, and Deafness DefaultPage Hearing, Ear Infections, and Deafness Diseases and Conditions Age-Related ... Neuropathy Auditory Processing Disorder Do You Need a Hearing Test? Ear Infections in Children Enlarged Vestibular Aqueducts (EVA) Hearing ...

47

Biochemical and subcellular distribution of arachidonic acid in rat myocardium  

Microsoft Academic Search

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

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

1987-01-01

48

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 ...

49

Arachidonic acid metabolism in human prostate cancer  

PubMed Central

The arachidonic acid pathway is important in the development and progression of numerous malignant diseases, including prostate cancer. To more fully evaluate the role of individual cyclooxygenases (COXs), lipoxygenases (LOXs) and their metabolites in prostate cancer, we measured mRNA and protein levels of COXs and LOXs and their arachidonate metabolites in androgen-dependent (LNCaP) and androgen-independent (PC-3 and DU145) prostate cancer cell lines, bone metastasis-derived MDA PCa 2a and MDA PCa 2b cell lines and their corresponding xenograft models, as well as core biopsy specimens of primary prostate cancer and nonneoplastic prostate tissue taken ex vivo after prostatectomy. Relatively high levels of COX-2 mRNA and its product PGE2 were observed only in PC-3 cells and their xenografts. By contrast, levels of the exogenous 12-LOX product 12-HETE were consistently higher in MDA PCa 2b and PC-3 cells and their corresponding xenograft tissues than were those in LNCaP cells. More strikingly, the mean endogenous level of 12-HETE was significantly higher in the primary prostate cancers than in the nonneoplastic prostate tissue (0.094 vs. 0.010 ng/mg protein, respectively; p=0.019). Our results suggest that LOX metabolites such as 12-HETE are critical in prostate cancer progression and that the LOX pathway may be a target for treating and preventing prostate cancer. PMID:22895552

YANG, PEIYING; CARTWRIGHT, CARRIE A.; LI, JIN; WEN, SIJIN; PROKHOROVA, INA N.; SHUREIQI, IMAD; TRONCOSO, PATRICIA; NAVONE, NORA M.; NEWMAN, ROBERT A.; KIM, JERI

2012-01-01

50

Ear problems in swimmers.  

PubMed

Acute diffuse otitis externa (swimmer's ear), otomycosis, exostoses, traumatic eardrum perforation, middle ear infection, and barotraumas of the inner ear are common problems in swimmers and people engaged in aqua activities. The most common ear problem in swimmers is acute diffuse otitis externa, with Pseudomonas aeruginosa being the most common pathogen. The symptoms are itching, otalgia, otorrhea, and conductive hearing loss. The treatment includes frequent cleansing of the ear canal, pain control, oral or topical medications, acidification of the ear canal, and control of predisposing factors. Swimming in polluted waters and ear-canal cleaning with cotton-tip applicators should be avoided. Exostoses are usually seen in people who swim in cold water and present with symptoms of accumulated debris, otorrhea and conductive hearing loss. The treatment for exostoses is transmeatal surgical removal of the tumors. Traumatic eardrum perforations may occur during water skiing or scuba diving and present with symptoms of hearing loss, otalgia, otorrhea, tinnitus and vertigo. Tympanoplasty might be needed if the perforations do not heal spontaneously. Patients with chronic otitis media with active drainage should avoid swimming, while patients who have undergone mastoidectomy and who have no cavity problems may swim. For children with ventilation tubes, surface swimming is safe in a clean, chlorinated swimming pool. Sudden sensorineural hearing loss and some degree of vertigo may occur after diving because of rupture of the round or oval window membrane. PMID:16138712

Wang, Mao-Che; Liu, Chia-Yu; Shiao, An-Suey; Wang, Tyrone

2005-08-01

51

?-Arrestin1 mediates nicotinic acid–induced flushing, but not its antilipolytic effect, in mice  

PubMed Central

Nicotinic acid is one of the most effective agents for both lowering triglycerides and raising HDL. However, the side effect of cutaneous flushing severely limits patient compliance. As nicotinic acid stimulates the GPCR GPR109A and Gi/Go proteins, here we dissected the roles of G proteins and the adaptor proteins, ?-arrestins, in nicotinic acid–induced signaling and physiological responses. In a human cell line–based signaling assay, nicotinic acid stimulation led to pertussis toxin–sensitive lowering of cAMP, recruitment of ?-arrestins to the cell membrane, an activating conformational change in ?-arrestin, and ?-arrestin–dependent signaling to ERK MAPK. In addition, we found that nicotinic acid promoted the binding of ?-arrestin1 to activated cytosolic phospholipase A2 as well as ?-arrestin1–dependent activation of cytosolic phospholipase A2 and release of arachidonate, the precursor of prostaglandin D2 and the vasodilator responsible for the flushing response. Moreover, ?-arrestin1–null mice displayed reduced cutaneous flushing in response to nicotinic acid, although the improvement in serum free fatty acid levels was similar to that observed in wild-type mice. These data suggest that the adverse side effect of cutaneous flushing is mediated by ?-arrestin1, but lowering of serum free fatty acid levels is not. Furthermore, G protein–biased ligands that activate GPR109A in a ?-arrestin–independent fashion may represent an improved therapeutic option for the treatment of dyslipidemia. PMID:19349687

Walters, Robert W.; Shukla, Arun K.; Kovacs, Jeffrey J.; Violin, Jonathan D.; DeWire, Scott M.; Lam, Christopher M.; Chen, J. Ruthie; Muehlbauer, Michael J.; Whalen, Erin J.; Lefkowitz, Robert J.

2009-01-01

52

Polyunsaturated fatty acids induce polarized submembranous F-actin aggregates and kill Entamoeba histolytica.  

PubMed

We have recently identified a novel galacto-glycerolipid (GGL) from the plant Oxalis corniculata that killed the human pathogen Entamoeba histolytica. In this study, we show that the anti-amoebic activity of GGL was due to the polyunsaturated fatty acid ?-linolenic acid (C18:3 ) side chain. Treatment of ?-linolenic acid to E. histolytica trophozoites disrupted the cytoskeletal network and led to polarization of F-actin at one end of the cells with prominent filopodial extensions. In addition, clustering of surface receptors and signaling molecules was also observed adjacent to the polarized actin similar to concanavalin-A-(Con-A) induced capping. But, in contrast to Con-A-induced capping, ?-linolenic acid induced caps were not shed and showed accumulation of long and numerous filopodia at the cap site. We found that ?-linolenic acid disrupts the actin cytoskeletal network, which led to the detachment of plasma membrane from the underlying cytoskeleton. A similar effect was observed with other dietary fatty acids such as linoleic acid (C18:2 ), arachidonic acid (C20:4 ), eicosapentaenoic acid (C20:5 ), and docosahexaenoic acid (C22:6 ). Our findings showed that dietary polyunsaturated fatty acids are powerful anti-amoebic agents that lead to disruption of the actin cytoskeleton. PMID:23568815

Manna, Dipak; Grewal, Jaspreet Singh; Sarkar, Bidyut; Maiti, Sudipta; Lohia, Anuradha

2013-05-01

53

Arachidonic acid and ion channels: an update  

PubMed Central

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

Meves, H

2008-01-01

54

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...

55

Luteolin prevents uric acid-induced pancreatic ?-cell dysfunction  

PubMed Central

Abstract Elevated uric acid causes direct injury to pancreatic ?-cells. In this study, we examined the effects of luteolin, an important antioxidant, on uric acid-induced ?-cell dysfunction. We first evaluated the effect of luteolin on nitric oxide (NO) formation in uric acid-stimulated Min6 cells using the Griess method. Next, we performed transient transfection and reporter assays to measure transcriptional activity of nuclear factor (NF)-?B. Western blotting assays were also performed to assess the effect of luteolin on the expression of MafA and inducible NO synthase (iNOS) in uric acid-treated cells. Finally, we evaluated the effect of luteolin on uric acid-induced inhibition of glucose-stimulated insulin secretion (GSIS) in Min6 cells and freshly isolated mouse pancreatic islets. We found that luteolin significantly inhibited uric acid-induced NO production, which was well correlated with reduced expression of iNOS mRNA and protein. Furthermore, decreased activity of NF-?B was implicated in inhibition by luteolin of increased iNOS expression induced by uric acid. Besides, luteolin significantly increased MafA expression in Min6 cells exposed to uric acid, which was reversed by overexpression of iNOS. Moreover, luteolin prevented uric acid-induced inhibition of GSIS in both Min6 cells and mouse islets. In conclusion, luteolin protects pancreatic ?-cells from uric acid-induced dysfunction and may confer benefit on the protection of pancreatic ?-cells in hyperuricemia-associated diabetes. PMID:25050113

Ding, Ying; Shi, Xuhui; Shuai, Xuanyu; Xu, Yuemei; Liu, Yun; Liang, Xiubin; Wei, Dong; Su, Dongming

2014-01-01

56

Ototoxicity (Ear Poisoning) (For Parents)  

MedlinePLUS

... part of the ear responsible for receiving/sending sounds and controlling balance — it's called ototoxicity or "ear ... have trouble hearing certain things, from high-pitched sounds to talking if there's background noise. Or they ...

57

The red ear syndrome  

PubMed Central

Red Ear Syndrome (RES) is a very rare disorder, with approximately 100 published cases in the medical literature. Red ear (RE) episodes are characterised by unilateral or bilateral attacks of paroxysmal burning sensations and reddening of the external ear. The duration of these episodes ranges from a few seconds to several hours. The attacks occur with a frequency ranging from several a day to a few per year. Episodes can occur spontaneously or be triggered, most frequently by rubbing or touching the ear, heat or cold, chewing, brushing of the hair, neck movements or exertion. Early-onset idiopathic RES seems to be associated with migraine, whereas late-onset idiopathic forms have been reported in association with trigeminal autonomic cephalalgias (TACs). Secondary forms of RES occur with upper cervical spine disorders or temporo-mandibular joint dysfunction. RES is regarded refractory to medical treatments, although some migraine preventative treatments have shown moderate benefit mainly in patients with migraine-related attacks. The pathophysiology of RES is still unclear but several hypotheses involving peripheral or central nervous system mechanisms have been proposed. PMID:24093332

2013-01-01

58

Ear Infections and Language Development.  

ERIC Educational Resources Information Center

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…

Roberts, Joanne E.; Zeisel, Susan A.

59

Drug delivery to the ear.  

PubMed

Drug delivery to the ear is used to treat conditions of the middle and inner ear such as acute and chronic otitis media, Ménière's disease, sensorineural hearing loss and tinnitus. Drugs used include antibiotics, antifungals, steroids, local anesthetics and neuroprotective agents. A literature review was conducted searching Medline (1966-2012), Embase (1988-2012), the Cochrane Library and Ovid (1966-2012), using search terms 'drug delivery', 'middle ear', 'inner ear' and 'transtympanic'. There are numerous methods of drug delivery to the middle ear, which can be categorized as topical, systemic (intravenous), transtympanic and via the Eustachian tube. Localized treatments to the ear have the advantages of targeted drug delivery allowing higher therapeutic doses and minimizing systemic side effects. The ideal scenario would be a carrier system that could cross the intact tympanic membrane loaded with drugs or biochemical agents for the treatment of middle and inner ear conditions. PMID:23323784

Hoskison, E; Daniel, M; Al-Zahid, S; Shakesheff, K M; Bayston, R; Birchall, J P

2013-01-01

60

Ear recognition: a complete system  

NASA Astrophysics Data System (ADS)

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

Abaza, Ayman; Harrison, Mary Ann F.

2013-05-01

61

Polychlorinated biphenyls induce arachidonic acid release in human platelets in a tamoxifen sensitive manner via  

E-print Network

" Polychlorinated biphenyls induce arachidonic acid release in human platelets in a tamoxifen and tamoxifen on PCB-induced arachidonic acid release in platelets were also investigated. Both nafoxidin and tamoxifen inhibited PCB-induced arachidonic acid release as well as 12-HETE and 12-HHT formation

Gelb, Michael

62

Elastotic nodules of the ears.  

PubMed

A case of bilateral elastotic nodules of the ears is reported. This distinctive entity occurs on the ears in response to chronic actinic damage and is seen infrequently. Elastotic nodules of the ears may therefore be misdiagnosed clinically as basal cell carcinoma or some infiltrative process such as gout or amyloid. Although the lesions are usually found on the anthelix, they may also arise on the helix, and can then simulate chondrodermatitis nodularis helicis. PMID:2612205

Requena, L; Aguilar, A; Sánchez Yus, E

1989-12-01

63

Save Your Ears  

NSDL National Science Digital Library

This game depicts a woman going through her day, faced with various loud sounds. In each situation, she has the choice of how to deal with the loud sound: Ear Plugs, Turn It Down, Move Away, or Do Nothing. You only have 3 of each choice available, symbolized by cards on screen. Your goal is to reach the end of the game with undamaged hearing and one set of earplugs, so you can enjoy an awesome rock concert. After each decision, you find out whether your hearing was damaged and if you made the best choice.

OMSI

2010-01-01

64

Effect of nimodipine on arachidonic acid metabolites after subarachnoid hemorrhage.  

PubMed

Arachidonic acid metabolites are under investigation as possible vasoactive agents involved in the pathogenesis of cerebral vasospasm after subarachnoid hemorrhage. Prostaglandins, as well as other vasoactive compounds, activate contractile proteins through utilization of extracellular bound Ca++ to the intracytoplasmic free fraction. Recently, calcium-antagonists, mainly Nimodipine, have been proposed for the prophylaxis and/or reversal of the ischemic damage caused by vasospasm. Nimodipine failed to reduce vasospasm incidence in a series of 30 patients admitted with diagnosis of subarachnoid hemorrhage from ruptured intracranial aneurysm. Nimodipine failed to reduce level of four arachidonate metabolites measured (prostaglandin D2, prostacyclin, thromboxane B2 and leukotriene C4) in lumbar and cisternal CSF. After subarachnoid hemorrhage there is a significant increase of CSF levels of arachidonate metabolites; in perianeurysmic cisterns level of prostaglandin D2, thromboxane B2 and leukotriene C4 are significantly higher than lumbar CSF levels. Moreover, cisternal CSF level of prostaglandin D2 and leukotriene C4 are significantly higher in patients with symptomatic vasospasm. Nimodipine did not significantly modify CFS level of arachidonate metabolites: this suggests that Nimodipine treatment, which definitely improves long-term results of patients for intracranial aneurysms, could exert its pharmacological action reducing Ca++ intake from the extracellular compartment and preventing a direct toxic effect of calcium, without a direct action against the release of vasoactive compounds. PMID:3120489

Rodriguez, R; Baena, Y; Gaetani, P; Grignani, G; Pacchiarini, L

1987-10-01

65

Arachidonic acid as a neurotoxic and neurotrophic substance  

Microsoft Academic Search

In this article we summarize a wide variety of properties of arachidonic acid (AA) in the mammalian nervous system especially in the brain. AA serves as a biologically-active signaling molecule as well as an important component of membrane lipids. Esterified AA is liberated from the membrane by phospholipase activity which is stimulated by various signals such as neurotransmitter-mediated rise in

Hiroshi Katsuki; Shoki Okuda

1995-01-01

66

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...

67

Ear, Nose & Throat Issues & Down Syndrome  

MedlinePLUS

... have frequent ear wax impactions that may impair hearing. Routine ear examinations can assess wax impactions, and periodic screening ... properly identified, it can be greatly improved with hearing aids, ear cleanings and environmental adaptations. Airway obstruction and Sleep ...

68

Elastotic nodules of the ear.  

PubMed

Eight cases of an elastotic degenerative lesion, developing on the ears in response to actinic damage are reported. Elastotic nodules may be diagnosed clinically as basal cell carcinoma, amyloid or even gout. Although usually found on the antihelix of the ear, they may arise on the helix and simulate chondrodermatitis nodularis helicis. PMID:7334162

Weedon, D

1981-12-01

69

Inner and outer ear anatomy  

NSDL National Science Digital Library

Sounds are actually waves from vibrations. The outer ear catches these waves and funnels them down into the inner ear. The waves reach the eardrum and in turn make the eardrum vibrate. Three small bones receive these vibrations next, then a snail shell-shaped structure called the cochlea. The cochlea is filled with liquid, and this liquid stimulates hairs inside the inner ear. The hairs transmit the signal to the auditory nerve where the signal is taken to the brain and processed as sound.

Zina Deretsky (National Science Foundation; )

2006-10-23

70

Arachidonic acid in aquaculture feeds: current status and future opportunities  

Microsoft Academic Search

The importance of arachidonic acid (20:4n?6, ARA) in fish nutrition has tended to be overlooked in preference to eicosapentaenoic (20:5n?3, EPA) and docosahexaenoic acids (22:6n?3, DHA), probably due to the predominance of the latter two HUFA in fish tissues. However, despite the abundance of EPA and DHA in fish tissues, the importance of ARA as the primary eicosanoid precursor has

J. Gordon Bell; John R. Sargent

2003-01-01

71

Enzymatic synthesis of structured lipid containing arachidonic and palmitic acids  

Microsoft Academic Search

Human milk fat contains 20–25% palmitic acid, and about 70% of the fatty acid is esterified to the 2-position of triglycerides.\\u000a It was also reported that arachidonic acid (AA) accelerated the growth of preterm infants. Thus, we attempted the synthesis\\u000a of 1,3-arachidonoyl-2-palmitoyl-glycerol by acidolysis of tripalmitin with AA using 1,3-specific Rhizopus delemar lipase. When a mixture of 10 g tripalmitin\\/AA

Yuji Shimada; Toshihiro Nagao; Yukiko Hamasaki; Kengo Akimoto; Akio Sugihara; Shigeaki Fujikawa; Sadao Komemushi; Yoshio Tominaga

2000-01-01

72

Responses of the Inner Ear toResponses of the Inner Ear to InfrasoundInfrasound  

E-print Network

Responses of the Inner Ear toResponses of the Inner Ear to InfrasoundInfrasound Alec N. Salt, Ph this TalkTake-Home Messages from this Talk · The ear is sensitive and responds to low frequency sounds Noise Floor Electrical recording from the guinea pig earElectrical recording from the guinea pig ear

Salt, Alec N.

73

Wonder Ears: Identification of Identical Twins from Ear Images Hossein Nejati  

E-print Network

Wonder Ears: Identification of Identical Twins from Ear Images Hossein Nejati , Li Zhang ,Terence explored automatic ear recognition for identical twin identification. Ear image recognition has been stud (performed manually). We here explore the possibility of automatic twin identification from their ear images

Sim, Terence

74

Arachidonic acid stimulates ⁴⁵calcium efflux and HPL release in isolated trophoblast cells  

Microsoft Academic Search

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 ⁴⁵Ca from perifused cells prelabelled with ⁴⁵Ca was

P. Zeitler; E. Murphy; S. Handwerger

1986-01-01

75

Increased isoprostane levels in oleic acid-induced lung injury  

SciTech Connect

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.

Ono, Koichi [Department of Anesthesiology and Resuscitation, Shinshu University School of Medicine, Matsumoto (Japan)] [Department of Anesthesiology and Resuscitation, Shinshu University School of Medicine, Matsumoto (Japan); Koizumi, Tomonobu, E-mail: tomonobu@shinshu-u.ac.jp [First Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto (Japan)] [First Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto (Japan); Tsushima, Kenji; Yoshikawa, Sumiko; Yokoyama, Toshiki [First Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto (Japan)] [First Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto (Japan); Nakagawa, Rikimaru [Department of Anesthesiology and Resuscitation, Shinshu University School of Medicine, Matsumoto (Japan)] [Department of Anesthesiology and Resuscitation, Shinshu University School of Medicine, Matsumoto (Japan); Obata, Toru [Department of Molecular Cell Biology, Institute of DNA Medicine, Jikei University School of Medicine, Tokyo (Japan)] [Department of Molecular Cell Biology, Institute of DNA Medicine, Jikei University School of Medicine, Tokyo (Japan)

2009-10-16

76

Acid-induced denaturation and refolding of prothrombin.  

PubMed

Structural transitions of the blood coagulation factor prothrombin (extracted from goat blood) in response to reduction of pH were investigated by fluorescence, circular dichroism and light scattering measurements. The study revealed the presence of a partially unfolded state at around pH 3.5, characterized by marked enhancement of fluorescence from ANS bound to the protein, increase of bimolecular rate constant for tryptophan fluorescence quenching and a sharp peak in the light scattering intensity. Further lowering of the pH caused reversal of the trend of variation of these parameters, suggesting that prothrombin folds back to a compact state containing native-like secondary structural elements. The refolded state at low pH (acid-induced denaturation process of several other monomeric proteins, and is a possible candidate for the class of folding intermediates known as molten globules. PMID:15950828

Debnath, Dilip Kumar; Mukhopadhyay, Kasturi; Basak, Soumen

2005-07-01

77

Valproic acid induces caspase 3-mediated apoptosis in microglial cells.  

PubMed

Valproic acid is widely used for the treatment of epilepsy and mood disorders, but its mode of action is unclear. Treatment of neuronal cells with valproic acid promotes neurite sprouting, is neuroprotective and drives neurogenesis; however its effects on non-neuronal brain cells are less clear. We report that valproic acid induces apoptosis in the mouse microglial cell line, BV-2, at concentrations within the therapeutic range. When BV-2 cells were incubated for 24 h with 500-1000 microM valproic acid we observed a reduction in cell number, the appearance of apoptotic morphology and increased caspase 3 cleavage. Exposure of a macrophage cell line (RAW 264.7) to similar concentrations of valproic acid also led to reduced cell number but no caspase 3 cleavage, suggesting these cells responded to valproic acid with reduced proliferation rather than apoptosis. This was confirmed using bromodeoxyuridine incorporation studies. Similar concentrations of valproic acid added to Neuro-2a, SK-N-SH and C6 cell lines as well as human NTera-2 astrocytes did not evoke cell death. The caspase 3 inhibitor DEVD-CHO inhibited valproic acid-induced apoptosis in BV-2 cells whereas the MEK inhibitor U0126 potentiated valproic acid-mediated apoptosis. These results demonstrate that valproic acid selectively induces apoptosis in BV-2 cells by way of a caspase 3-mediated action. As activated microglia secrete neurotoxins in neurodegenerative diseases such as Alzheimer's, Parkinson's, and HIV dementia, valproic acid may alleviate these diseases by selectively killing microglia. PMID:16600518

Dragunow, M; Greenwood, J M; Cameron, R E; Narayan, P J; O'Carroll, S J; Pearson, A G; Gibbons, H M

2006-07-21

78

Arachidonic acid stimulates internalisation of leptin by human placental choriocarcinoma (BeWo) cells.  

PubMed

Arachidonic acid at 100 nM stimulated internalisation of 125I-leptin in human placental choriocarcinoma (BeWo) cells by 3-fold compared with controls. In contrast, eicosapentaenoic acid at similar concentration decreased internalisation of leptin by 2-fold. Use of ibuprofen and indomethacin (inhibitors of prostaglandin synthesis) inhibited the stimulatory effect of arachidonic acid. Prostaglandin E(2), a cyclooxygenase metabolite of arachidonic acid, stimulated internalisation of leptin by these cells. All these data demonstrate that stimulation of leptin internalisation by arachidonic acid in placental trophoblasts may be mediated via prostaglandin E(2). PMID:12445819

Duttaroy, Asim K; Taylor, Jonathon; Gordon, Margaret J; Hoggard, Nigel; Campbell, Fiona M

2002-12-01

79

Inflammatory diseases of the ear.  

PubMed

The inflammatory diseases of external and middle ear are one of the commonest conditions encountered by the pediatric physician. Inner ear inflammations are less common and need special and urgent attention. Special management in each case requires detailed history, examination, necessary investigations and appropriate referral to otolaryngologist when necessary. The article is aimed to help formulate a plan in managing the inflammatory conditions of ear. Otalgia constitutes the most prominent of the symptoms in external and middle ear inflammations whereas vertigo, tinnitus and sensory hearing loss form the symptom complex for inner ear infections. It is necessary to understand the basic pathophysiology of the inflammatory condition to be able to institute a targetted treatment. The audiometry impedance studies, microbiology of discharge and occasionally ABR and CT scan from the mainstay of investigative workup. The treatment is specific and based on the precise diagnosis. It often requires the help of an otolaryngologist. Decisions may have to be made with regards to the need for any surgical intervention particularly in acute otitis media, an external canal abscess or an acute mastoiditis. A case of chronic otitis media with facial palsy or vertigo (labyrinthitis being a possibility) needs urgent intervention. PMID:10771916

Cheng, A T; Young, N M

1997-01-01

80

3D printed bionic ears.  

PubMed

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

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

81

Ear recognition based on edge potential function  

NASA Astrophysics Data System (ADS)

The use of ear information for people identification has been under testing at least for 100 years. However, it is still an open issue if the ears can be considered unique or unique enough to be used as biometric feature. In this paper a biometric system for human identification based on ear recognition is presented. The ear is modeled as a set of contours extracted from the ear image with an edge potential function. The matching algorithm has been tested in presence of several image modifications. Two human ear databases have been used for the tests. The experimental results show the effectiveness of the proposed scheme.

Battisti, F.; Carli, M.; De Natale, F. G. B.; Neri, A.

2012-03-01

82

A biomechanical ear model to evaluate middle-ear reconstruction.  

PubMed

In order to evaluate the efficiency of middle-ear prostheses in near-real conditions, an artificial model was developed that approximately simulates the actual geometrical and biomechanical properties of the ear system (excluding the ossicular chain). The sound transmission characteristics of selected commercial middle-ear prostheses and of a synthetic test material were measured using laser Doppler vibrometry (LDV) in this model. The model's realistic properties enabled clinical tympanometry to be used to control the stiffness. In addition the influences of the implant mass on transmission characteristics were investigated. With an averaged displacement between 10 and 100 nm/Pa up to 2000 Hz, the transmission characteristic of the model was comparable with data obtained from the intact middle ear in temporal bone experiments. From the acoustical point of view, no significant material-specific differences could be found. Increasing the mass of the implants to more than 50 mg results in poorer acoustic transmission. In general, changes to the stiffness involving compliance values greater than 3.5 ml and smaller than 0.2 ml led to poorer acoustic transmission. PMID:20017684

Mojallal, Hamidreza; Stieve, Martin; Krueger, Ilka; Behrens, Peter; Mueller, Peter P; Lenarz, Thomas

2009-12-01

83

Arachidonic acid and arachidonoyldiglycerols increase in rat cerebrum during bicuculline-induced status epilepticus  

Microsoft Academic Search

Bicuculline-induced status epilepticus was found to be associated with increased amounts offree fatty acids and diacylglycerols in the rat cerebrum. The predominant fatty acid in both lipid pools was arachidonic acid. The accumulation of arachidonoyl-diglycerols decreased at the time of and during behavioral seizures induced by bicuculline, while the amount of free arachidonic acid appeared to increase. We propose a

Nicolas G. Bazan; Susana A. Morelli de Liberti; Elena B. Rodriguez de Turco

1982-01-01

84

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

PubMed Central

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

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

2014-01-01

85

Altered arachidonic acid metabolism and platelet size in atopic subjects  

SciTech Connect

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.

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

1988-03-01

86

Computerized image analysis for acetic acid induced intraepithelial lesions  

NASA Astrophysics Data System (ADS)

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.

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

2008-03-01

87

Metformin Protects Rat Hepatocytes against Bile Acid-Induced Apoptosis  

PubMed Central

Background Metformin is used in the treatment of Diabetes Mellitus type II and improves liver function in patients with non-alcoholic fatty liver disease (NAFLD). Metformin activates AMP-activated protein kinase (AMPK), the cellular energy sensor that is sensitive to changes in the AMP/ATP-ratio. AMPK is an inhibitor of mammalian target of rapamycin (mTOR). Both AMPK and mTOR are able to modulate cell death. Aim To evaluate the effects of metformin on hepatocyte cell death. Methods Apoptotic cell death was induced in primary rat hepatocytes using either the bile acid glycochenodeoxycholic acid (GCDCA) or TNF? in combination with actinomycin D (actD). AMPK, mTOR and phosphoinositide-3 kinase (PI3K)/Akt were inhibited using pharmacological inhibitors. Apoptosis and necrosis were quantified by caspase activation, acridine orange staining and Sytox green staining respectively. Results Metformin dose-dependently reduces GCDCA-induced apoptosis, even when added 2 hours after GCDCA, without increasing necrotic cell death. Metformin does not protect against TNF?/ActD-induced apoptosis. The protective effect of metformin is dependent on an intact PI3-kinase/Akt pathway, but does not require AMPK/mTOR-signaling. Metformin does not inhibit NF-?B activation. Conclusion Metformin protects against bile acid-induced apoptosis and could be considered in the treatment of chronic liver diseases accompanied by inflammation. PMID:23951244

Woudenberg-Vrenken, Titia E.; Conde de la Rosa, Laura; Buist-Homan, Manon; Faber, Klaas Nico; Moshage, Han

2013-01-01

88

Fetal surfactant as a source of arachidonate in human amniotic fluid.  

PubMed

The factors responsible for the onset of labor in women are not well understood but it is clear that parturition is associated with increased production of prostanoids and release of arachidonic acid by intrauterine tissues. Pulmonary surfactant is secreted from the fetal lung into the amniotic fluid where its concentration increases toward term. In this paper we have shown that the ability of fetal surfactant to stimulate prostaglandin production by amnion cells is greatly enhanced by pre-incubating surfactant with amniotic fluid. This is due to the release of fatty acids, including arachidonate, from the lipids of fetal surfactant by the sequential action of phospholipase C and diglyceride lipase. Thus, in addition to providing the amnion with a source of arachidonate derived from the intracellular transfer of arachidonate from surfactant phosphatidylcholine to phosphatidylethanolamine and phosphatidylinositol in amnion cells, fetal surfactant also contributes to the pool of free arachidonate in amniotic fluid. PMID:10680776

Bernal, A L; Phizackerley, P J

2000-01-01

89

Physiological functioning of the ear and masking  

NASA Technical Reports Server (NTRS)

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.

1984-01-01

90

21 CFR 878.3590 - Ear prosthesis.  

... 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. An ear prosthesis is a...

2014-04-01

91

21 CFR 878.3590 - Ear prosthesis.  

Code of Federal Regulations, 2013 CFR

... 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. An ear prosthesis is a...

2013-04-01

92

21 CFR 878.3590 - Ear prosthesis.  

Code of Federal Regulations, 2011 CFR

... 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. An ear prosthesis is a...

2011-04-01

93

21 CFR 878.3590 - Ear prosthesis.  

Code of Federal Regulations, 2012 CFR

... 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. An ear prosthesis is a...

2012-04-01

94

21 CFR 878.3590 - Ear prosthesis.  

Code of Federal Regulations, 2010 CFR

... 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. An ear prosthesis is a...

2010-04-01

95

Ear Recognition Based on Gabor Features and KFDA  

PubMed Central

We propose an ear recognition system based on 2D ear images which includes three stages: ear enrollment, feature extraction, and ear recognition. Ear enrollment includes ear detection and ear normalization. The ear detection approach based on improved Adaboost algorithm detects the ear part under complex background using two steps: offline cascaded classifier training and online ear detection. Then Active Shape Model is applied to segment the ear part and normalize all the ear images to the same size. For its eminent characteristics in spatial local feature extraction and orientation selection, Gabor filter based ear feature extraction is presented in this paper. Kernel Fisher Discriminant Analysis (KFDA) is then applied for dimension reduction of the high-dimensional Gabor features. Finally distance based classifier is applied for ear recognition. Experimental results of ear recognition on two datasets (USTB and UND datasets) and the performance of the ear authentication system show the feasibility and effectiveness of the proposed approach. PMID:24778595

Mu, Zhichun

2014-01-01

96

Effects of Middle-Ear Disorders on Power Reflectance Measured in Cadaveric Ear Canals  

E-print Network

Effects of Middle-Ear Disorders on Power Reflectance Measured in Cadaveric Ear Canals Susan E. Voss,1 Gabrielle R. Merchant,2 and Nicholas J. Horton3 Objective: Reflectance measured in the ear canal offers a noninvasive method to monitor the acoustic properties of the middle ear, and few systematic

Allen, Jont

97

The caecilian ear: further observations.  

PubMed

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

Wever, E G; Gans, C

1976-10-01

98

Reconstruction of middle ear malformations  

PubMed Central

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

Schwager, Konrad

2008-01-01

99

[Tympanoplasty on only hearing ears].  

PubMed

Tympanoplasty on only hearing ears was performed on 11 patients in Osaka University Hospital and Osaka Rosai Hospital during 1986 1994; this was 0.68% of all cases of middle ear surgery. The patients consisted of 5 with cholesteatoma, 5 with chronic otitis media and 1 with cholesterin granuloma. The mean age was 47.6 years (13-68 years) and the mean follow-up period was 2 years and 7 months (6 months-4 years). Postoperative hearing results was obtained in 9 patients (81.8%) according to the criteria of Otology Japan (1987), and all ears were dry at the final examination. Compared with the preoperative hearing level, postoperative hearing level showed improvement in 3 cases, not in 7 cases (within difference of 5 dB) and deterioration by 10-15 dB in 1 case. Although indications for surgery on only hearing ears are still controversial, we suggest the following: 1) patients with cholesteatoma should be operated on in the ordinary way; 2) patients with chronic otitis media should be operated on only by myringoplasty; 3) all patients must be operated on very carefully by skillful surgeons. PMID:8776969

Sakagami, M; Ogasawara, H; Node, M; Seo, T; Mishiro, Y; Okumura, S

1996-07-01

100

Middle Ear Infections (For Parents)  

MedlinePLUS

After the common cold , ear infections are the most frequently diagnosed childhood illness in the United States. Most kids will have had ... winter season, when lots of people get upper respiratory tract infections or colds. Signs and Symptoms The signs and ...

101

Frog eye, ear, and nostril  

NSDL National Science Digital Library

You can clearly see the frog's eye. There is an air opening near a black spot on the frog's skin. The opening to the frog's ear is covered by the round, tan membrane to the left in the picture. This membrane is called the tympanum.

Ren West (None;)

2006-08-07

102

Mechanics of the frog ear  

PubMed Central

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

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

2010-01-01

103

EAR TO THE GROUND IN THIS ISSUE  

E-print Network

EAR TO THE GROUND IN THIS ISSUE Update from the Division Director 1 New Program Officer Dr. Jonathan Wynn 2 Meet the EAR Staff 3 Broader Impacts ­ Examples from the Ground 3 The Division of Earth Sciences (EAR) is part of the Geosciences Directorate at the National Science Foundation. News from

104

Ear Biometrics in Human Identification A Dissertation  

E-print Network

Ear Biometrics in Human Identification A Dissertation Submitted to the Graduate School and Engineering Notre Dame, Indiana June 2006 #12;Ear Biometrics in Human Identification Abstract by Ping Yan the ear as a biometric and investigate its potential with both 2D and 3D data. Our work is the largest

Bowyer, Kevin W.

105

Designing Medical Devices for the Ear  

NSDL National Science Digital Library

Students are introduced to engineering, specifically to biomedical engineering and the engineering design process, through a short lecture and an associated hands-on activity in which they design their own medical devices for retrieving foreign bodies from the ear canal. Through the lesson, they learn the basics of ear anatomy and how ear infections occur and are treated. Besides antibiotic treatment, the most common treatment for chronic ear infections is the insertion of ear tubes to drain fluid from the middle ear space to relieve pressure on the ear drum. Medical devices for this procedure, a very common children's surgery, are limited, sometimes resulting in unnecessary complications from a simple procedure. Thus, biomedical engineers must think creatively to develop new solutions (that is, new and improved medical devices/instruments) for inserting ear tubes into the ear drum. The class learns the engineering design process from this ear tube example of a medical device design problem. In the associated activity, students explore biomedical engineering on their own by designing prototype medical devices to solve another ear problem commonly experienced by children: the lodging of a foreign body (such as a pebble, bead or popcorn kernel) in the ear canal. The activity concludes by teams sharing and verbally analyzing their devices.

2014-09-18

106

Immunologic Disorders of the Inner Ear.  

ERIC Educational Resources Information Center

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)

Kinney, William C.; Hughes, Gordon B.

1997-01-01

107

Can Loud Music Hurt My Ears?  

MedlinePLUS

... Main Page The Pink Locker Society Can Loud Music Hurt My Ears? KidsHealth > Kids > Q&A > Q & A > 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 ...

108

High dose of ascorbic acid induces cell death in mesothelioma cells.  

PubMed

Malignant mesothelioma is an asbestos-related fatal disease with no effective cure. Recently, high dose of ascorbate in cancer treatment has been reexamined. We studied whether high dose of ascorbic acid induced cell death of four human mesothelioma cell lines. High dose of ascorbic acid induced cell death of all mesothelioma cell lines in a dose-dependent manner. We further clarified the cell killing mechanism that ascorbic acid induced reactive oxygen species and impaired mitochondrial membrane potential. In vivo experiment, intravenous administration of ascorbic acid significantly decreased the growth rate of mesothelioma tumor inoculated in mice. These data suggest that ascorbic acid may have benefits for patients with mesothelioma. PMID:20171954

Takemura, Yukitoshi; Satoh, Motohiko; Satoh, Kiyotoshi; Hamada, Hironobu; Sekido, Yoshitaka; Kubota, Shunichiro

2010-04-01

109

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

NASA Astrophysics Data System (ADS)

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

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

2009-02-01

110

Dynamic Simulations on the Arachidonic Acid Metabolic Network  

PubMed Central

Drug molecules not only interact with specific targets, but also alter the state and function of the associated biological network. How to design drugs and evaluate their functions at the systems level becomes a key issue in highly efficient and low–side-effect drug design. The arachidonic acid metabolic network is the network that produces inflammatory mediators, in which several enzymes, including cyclooxygenase-2 (COX-2), have been used as targets for anti-inflammatory drugs. However, neither the century-old nonsteriodal anti-inflammatory drugs nor the recently revocatory Vioxx have provided completely successful anti-inflammatory treatment. To gain more insights into the anti-inflammatory drug design, the authors have studied the dynamic properties of arachidonic acid (AA) metabolic network in human polymorphous leukocytes. Metabolic flux, exogenous AA effects, and drug efficacy have been analyzed using ordinary differential equations. The flux balance in the AA network was found to be important for efficient and safe drug design. When only the 5-lipoxygenase (5-LOX) inhibitor was used, the flux of the COX-2 pathway was increased significantly, showing that a single functional inhibitor cannot effectively control the production of inflammatory mediators. When both COX-2 and 5-LOX were blocked, the production of inflammatory mediators could be completely shut off. The authors have also investigated the differences between a dual-functional COX-2 and 5-LOX inhibitor and a mixture of these two types of inhibitors. Their work provides an example for the integration of systems biology and drug discovery. PMID:17381237

Yang, Kun; Ma, Wenzhe; Liang, Huanhuan; Ouyang, Qi; Tang, Chao; Lai, Luhua

2007-01-01

111

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...

112

Inner Time and Inner Ear  

E-print Network

Sounds are information sequences that cannot exist outside of a time base and therefore cannot be analyzed inside an animal without an accurate internal clock. It is suggested that the clock may be hidden in the inner ear. It is shown that if a mechanism of counting of the electrical charge passing through the inner ear hair cells exists then the mechanism can be used both for the conversion of acceleration into velocity and as the inner clock, in the presence of a constant current. The causes of vertigo during rotation are discussed. It is shown that if a continuous inner time exists then sleeping is a "mathematical necessity". It is indicated that both for visual and hearing inputs the recognition of an input signal is recognition of function(s) of two variables.

Michael Rvachov

2012-10-30

113

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

NASA Astrophysics Data System (ADS)

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.

Delnavaz, Aidin; Voix, Jérémie

2013-02-01

114

Lipoxygenase metabolites of arachidonic acid as second messengers for presynaptic inhibition of Aplysia sensory cells  

NASA Astrophysics Data System (ADS)

Biochemical and biophysical studies on Aplysia sensory neurons indicate that inhibitory responses to the molluscan peptide FMRFamide are mediated by lipoxygenase metabolites of arachidonic acid. These compounds are a new class of second messengers in neurons.

Piomelli, D.; Volterra, A.; Dale, N.; Siegelbaum, S. A.; Kandel, E. R.; Schwartz, J. H.; Belardetti, F.

1987-07-01

115

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

NASA Astrophysics Data System (ADS)

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

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

2013-06-01

116

Inhibition of protein synthesis in intact mammalian cells by arachidonic acid.  

PubMed Central

Optimal translation initiation in intact mammalian cells requires sequestered intracellular Ca2+. Arachidonic acid, which releases sequestered Ca2+ from cells and isolated organelles, was studied to assess its potential role in the regulation of protein synthesis via Ca2+ mobilization. Unsaturated fatty acids at microM concentrations inhibited protein synthesis in intact GH2 pituitary, C6 glial tumour and HeLa cells in a manner dependent on degree of unsaturation and cell number. Arachidonate was generally the most, and the fully saturated arachidic acid the least, potent of the fatty acids tested. At 2 x 10(6) GH3 cells/ml, amino incorporation into a broad spectrum of polypeptides was inhibited by 80-90% by 10-20 microM fatty acid. Inhibition was maximal at 4-8 min and was attenuated by 1-2 h and more pronounced at lower pH. Protein synthesis was maximally inhibited when arachidonate mobilized approx. 40% of cell-associated Ca2+. At lower concentrations (10 microM) arachidonate suppressed translational initiation, with the inhibition being reversed as extracellular Ca2+ concentrations were increased to supraphysiological values. At higher concentrations (20 microM) arachidonate inhibited peptide-chain elongation in a Ca(2+)-independent manner. Arachidonate also blocked elongation in reticulocyte lysates. The effects of arachidonate in intact cells were reversible with time via its metabolism or by washes containing BSA. Sufficient arachidonate appears to be synthesized during ischaemic stress to inhibit translation by either mechanism. Images Fig. 2. PMID:1546963

Rotman, E I; Brostrom, M A; Brostrom, C O

1992-01-01

117

Arachidonic acid metabolism in murine lymphoma cell sublines differing in radiation sensitivity  

Microsoft Academic Search

14C arachidonic acid incorporation and 14C radioactivity release as well as prostaglandin (PG) and 5-hydroxyeicosatetraenoic acid (5-HETE) synthesis were measured in the pair of murine lymphoma L5178Y (LY) cell sublines differing in radiation sensitivity. Both LY sublines, LY-R (resistant) and LY-S (sensitive), incorporated exogenous arachidonic acid and released it from membrane phospholipids. Ca2+ ionophores (ionomycin and A23187) but not PMA

Barbara Sochanowicz; Irena Szumiel

1996-01-01

118

Influence of fatty acid ethanolamides and ? 9-tetrahydrocannabinol on cytokine and arachidonate release by mononuclear cells  

Microsoft Academic Search

The effects of arachidonic acid ethanolamide (anandamide), palmitoylethanolamide and ?9-tetrahydrocannabinol on the production of tumor necrosis factor-? (TNF-?), interleukin-4, interleukin-6, interleukin-8, interleukin-10, interferon-?, p55 and p75 TNF-? soluble receptors by stimulated human peripheral blood mononuclear cells as well as [3H]arachidonic acid release by non-stimulated and N-formyl-Met–Leu–Phe (fMLP)-stimulated human monocytes were investigated. Anandamide was shown to diminish interleukin-6 and interleukin-8 production

Evguenii V Berdyshev; Elisabeth Boichot; Noëlla Germain; Nathalie Allain; Jean-Pierre Anger; Vincent Lagente

1997-01-01

119

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

PubMed Central

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

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

120

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

SciTech Connect

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.

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

1986-01-13

121

Molecular Mechanisms of Inner Ear Development  

PubMed Central

The inner ear is a structurally complex vertebrate organ built to encode sound, motion, and orientation in space. Given its complexity, it is not surprising that inner ear dysfunction is a relatively common consequence of human genetic mutation. Studies in model organisms suggest that many genes currently known to be associated with human hearing impairment are active during embryogenesis. Hence, the study of inner ear development provides a rich context for understanding the functions of genes implicated in hearing loss. This chapter focuses on molecular mechanisms of inner ear development derived from studies of model organisms. PMID:22855724

Wu, Doris K.; Kelley, Matthew W.

2012-01-01

122

Fear the EAR: Discovering and Mitigating Execution After Redirect Vulnerabilities  

E-print Network

Fear the EAR: Discovering and Mitigating Execution After Redirect Vulnerabilities Adam Doupé, Bryce Execution After Redirect, or EAR. A web application de- veloper can introduce an EAR by calling a redirect web frameworks are to EAR vulnerabilities. We then discuss the results from the EAR challenge

California at Santa Barbara, University of

123

Cytochrome P450 arachidonic acid metabolism in bovine corneal epithelium  

SciTech Connect

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.

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

1986-03-01

124

Effects of arachidonic acid metabolites on airway sensors.  

PubMed

Arachidonic acid (AA) in the cell membrane produces a variety of metabolites by different enzymatic pathways. These lipid metabolites, along with other mediators, play an important role in the inflammatory processes. Many of them can bind directly to the receptors on the sensory endings and initiate electrical impulses to be transmitted to the central nervous system, causing reflex responses. These bioactive AA metabolites may also alter the lung mechanics (mechanical environment of the sensory ending), and in turn, stimulate sensory afferents. In addition, some metabolites may sensitize the sensory endings and make them more responsive to other mechanical or chemical stimulation. These metabolites may also induce other mediators and modulators to cause physiological effects. Furthermore, some of them may attract inflammatory cells to produce a localized effect. In short, AA metabolites may come from different sources and act through multiple pathways to stimulate airway sensors. This brief review is intended to illustrate the underlying mechanisms and help elucidate the inflammatory process in the airways. PMID:17437035

Lin, Shu-Xin; Yu, Jerry

2007-04-25

125

Arachidonate 12-lipoxygenases with reference to their selective inhibitors  

SciTech Connect

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.

Yamamoto, Shozo [Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women's University, Imakumano, Higashiyama-ku, Kyoto 605-8501 (Japan)]. E-mail: yamamosh@kyoto-wu.ac.jp; Katsukawa, Michiko [Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women's University, Imakumano, Higashiyama-ku, Kyoto 605-8501 (Japan); Nakano, Ayumi [Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women's University, Imakumano, Higashiyama-ku, Kyoto 605-8501 (Japan); Hiraki, Emi [Department of Food and Nutrition, Faculty of Home Economics, Kyoto Women's University, Imakumano, Higashiyama-ku, Kyoto 605-8501 (Japan); Nishimura, Kohji [Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane 690-8504 (Japan); Jisaka, Mitsuo [Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane 690-8504 (Japan); Yokota, Kazushige [Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane 690-8504 (Japan); Ueda, Natsuo [Department of Biochemistry, School of Medicine, Kagawa University, Miki-cho, Kita-gun, Kagawa 761-0793 (Japan)

2005-12-09

126

Dietary arachidonic acid in perinatal nutrition: a commentary.  

PubMed

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.Pediatric Research (2014); doi:10.1038/pr.2014.166. PMID:25314584

Lauritzen, Lotte; Fewtrell, Mary; Agostoni, Carlo

2014-10-14

127

Ancestral genetic complexity of arachidonic acid metabolism in Metazoa.  

PubMed

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

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

2014-09-01

128

Acute nicotine reduces brain arachidonic acid signaling in unanesthetized rats  

PubMed Central

Nicotine exerts its central effects by activating pre- and post-synaptic nicotinic acetylcholine receptors (nAChRs). Pre-synaptic nAChRs modulate the release of many neurotransmitters that bind to post-synaptic receptors. These may be coupled to the activation of cytosolic phospholipase A2 (cPLA2), which hydrolyzes arachidonic acid (AA) from membrane phospholipids. We hypothesized that nicotine would modify brain signaling involving AA by binding to nAChRs. Nicotine (0.1 mg/kg s.c.) or saline was injected 2 or 10 min before infusing [1-14C]AA in unanesthetized rats. The AA incorporation coefficient k* (a marker of the AA signal) was measured in 80 brain regions by quantitative autoradiography. Nicotine, compared to saline, when given 2 min before [1-14C]AA, significantly decreased k* for AA in 26 regions, including cerebral cortex, thalamus and habenula-interpeduncular regions, by 13% to 45%. These decreases could be entirely prevented by pretreatment with mecamylamine (1.0 mg/kg s.c.). When given 10 min before [1-14C]AA, nicotine did not alter any value of k*. In summary, nicotine given to unanesthetized rats rapidly reduces signaling involving AA in brain regions containing nAChRs, likely by modulating pre-synaptic release of neurotransmitters. The effect shows rapid desensitization and is produced at a nicotine dose equivalent to smoking one cigarette in humans. PMID:19142197

Chang, Lisa; Rapoport, Stanley I.; Nguyen, Henry N.; Greenstein, Dede; Chen, Mei; Basselin, Mireille

2009-01-01

129

Pediatric Obesity and Ear, Nose, and Throat Disorders  

MedlinePLUS

Pediatric Obesity and Ear, Nose, and Throat Disorders Pediatric Obesity and Ear, Nose, and Throat Disorders Patient Health Information ... self-esteem, and isolation from their peers. Pediatric obesity and otolaryngic problems Otolaryngologists, or ear, nose, and ...

130

Cutaneous lesions of the external ear  

PubMed Central

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

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

2008-01-01

131

Cutaneous lesions of the external ear  

Microsoft Academic Search

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

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

2008-01-01

132

Playing by Ear: Foundation or Frill?  

ERIC Educational Resources Information Center

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…

Woody, Robert H.

2012-01-01

133

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...

134

Review Article Mechanics of the frog ear  

E-print Network

Review Article Mechanics of the frog ear Pim Van Dijk a,b,*, Matthew J. Mason c , Richard L s t r a c t The frog inner ear contains three regions that are sensitive to airborne sound and which of the frog's auditory range. It shares the ability to generate both evoked and spontaneous otoacoustic

Allen, Jont

135

"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 ...

136

Gene therapy for the inner ear  

PubMed Central

Animal studies on inner ear development, repair and regeneration provide understanding of molecular pathways that can be harnessed for treating inner ear disease. Use of transgenic mouse technology, in particular, has contributed knowledge of genes that regulate development of hair cells and innervation, and of molecular players that can induce regeneration, but this technology is not applicable for human treatment, for practical and ethical reasons. Therefore other means for influencing gene expression in the inner ear are needed. We describe several gene vectors useful for inner ear gene therapy and the practical aspects of introducing these vectors into the ear. We then review the progress toward using gene transfer for therapies in both auditory and balance systems, and discuss the technological milestones needed to advance to clinical application of these methods. PMID:23265411

Fukui, Hideto; Raphael, Yehoash

2012-01-01

137

[Cochlear damage caused by middle ear surgeries].  

PubMed

A prospective study was set up to study the reaction of the cochlea after the trauma of middle-ear surgery. For this purpose, the bone conduction of 50 patients was tested every day, beginning on the first post-operative day. To collect information on possible damaging mechanisms, three surgical techniques were studied: Stapes surgery with the opening of the inner ear; mastoidectomy with drill-generated noise; tympanoplasty with manipulations at the stapes. The comparison of the bone conduction thresholds with audiometry results after completed healing of the ear, disclosed that even under the ear-packing, bone conduction can give reliable information on cochlea function, if a 10-15 dB variance due to methodological causes is taken into account. Excessive drilling may result in a temporary threshold shift, which has already resolved at the time of unpacking the ear. No signs of hydraulic damage after manipulation at the stapes could be discovered. PMID:2029305

Hüttenbrink, K B

1991-02-01

138

Biometric recognition using 3D ear shape.  

PubMed

Previous works have shown that the ear is a promising candidate for biometric identification. However, in prior work, the preprocessing of ear images has had manual steps and algorithms have not necessarily handled problems caused by hair and earrings. We present a complete system for ear biometrics, including automated segmentation of the ear in a profile view image and 3D shape matching for recognition. We evaluated this system with the largest experimental study to date in ear biometrics, achieving a rank-one recognition rate of 97.8 percent for an identification scenario and an equal error rate of 1.2 percent for a verification scenario on a database of 415 subjects and 1,386 total probes. PMID:17568136

Yan, Ping; Bowyer, Kevin W

2007-08-01

139

Niacin Sensitivity and the Arachidonic Acid Pathway in Schizophrenia  

PubMed Central

Objective Schizophrenia is associated with a blunted flush response to niacin. Since niacin-induced skin flushing is mediated by vasodilators derived from arachidonic acid (AA), we tested whether the blunted flush response to niacin is a marker of AA deficiency. Methods Eight concentrations of methylnicotinate were applied to the forearms of 20 adults with schizophrenia and 20 controls. Laser Doppler measurement of blood flow responses was used to derive values for niacin sensitivity (defined as the concentration eliciting half-maximal response, i.e., EC50 value) and efficacy (defined as the maximal evoked blood flow response). RBC membrane fatty acids were analyzed by gas chromatography. Results Niacin sensitivity and efficacy were reduced in schizophrenia. In the control group, there was significant correlation between AA levels and niacin sensitivity as well as a trend toward correlation between AA levels and niacin efficacy. In contrast, neither sensitivity nor efficacy of niacin correlated with AA levels in schizophrenia. An expected correlation between the levels of AA and its elongation product (adrenic acid) was absent in schizophrenia. Adrenic acid levels correlated with niacin efficacy in schizophrenia. Conclusions The schizophrenia-associated niacin response abnormality involves both diminished sensitivity and reduced efficacy. The lack of expected correlation between levels of AA and adrenic acid suggests homeostatic imbalance within the n-6 polyunsaturated fatty acid (PUFA) pathway in schizophrenia. Though AA levels were unrelated to measures of niacin response in schizophrenia, the correlation between adrenic acid and niacin efficacy in schizophrenia suggests relevance of the n-6 PUFA pathway to the blunted niacin response. PMID:20417059

Messamore, Erik; Hoffman, William F.; Yao, Jeffrey K.

2010-01-01

140

Bias-dependent amino-acid-induced conductance changes in short semi-metallic carbon nanotubes  

E-print Network

Bias-dependent amino-acid-induced conductance changes in short semi-metallic carbon nanotubes G the interaction between short semi-metallic carbon nanotubes and different amino acids using molecular dynamics different mechanisms of nanotube-conductance-change upon adsorption of amino acids: one due to the change

Pulfrey, David L.

141

Abscisic Acid Induces Formation of Floating Leaves in the Heterophyllous Aquatic Angiosperm Potamogeton nodosus  

Microsoft Academic Search

Potamogeton nodosus tubers produce floating-type instead of submersed-type leaves when exposed to 10-5 molar synthetic abscisic acid. Abscisic acid-induced leaves have stomata on upper leaf surfaces and higher widthllength ratios than controls. These effects are wholly or partially overcome by simultaneous exposure to abscisic acid combined with gibberellic acid, kinetin, or benzyladenine.

Lars W. J. Anderson

1978-01-01

142

Abscisic Acid Induces Formation of Floating Leaves in the Heterophyllous Aquatic Angiosperm Potamogeton nodosus.  

PubMed

Potamogeton nodosus tubers produce floating-type instead of submersed-type leaves when exposed to 10(-5) molar synthetic abscisic acid. Abscisic acid-induced leaves have stomata on upper leaf surfaces and higher width/length ratios than controls. These effects are wholly or partially overcome by simultaneous exposure to abscisic acid combined with gibberellic acid, kinetin, or benzyladenine. PMID:17830317

Anderson, L W

1978-09-22

143

The Placebo Response to Citric Acid-induced Cough: Pharmacodynamics and Gender Differences  

Microsoft Academic Search

Characteristics of the response to placebo in a citric acid-induced cough challenge were investigated as part of a randomized, double-blind crossover trial to assess the antitussive effect of dextromethorphan. Baseline cough responses were established on two occasions in 22 healthy subjects. They received 60 ml placebo antitussive syrup and cough frequency following five inhalations of 10% citric acid over 5

A. Rostami-Hodjegan; R. Abdul-Manap; C. E. Wright; G. T. Tucker; A. H. Morice

2001-01-01

144

GPR109A (PUMA-G/HM74A) mediates nicotinic acid–induced flushing  

PubMed Central

Nicotinic acid (niacin) has long been used as an antidyslipidemic drug. Its special profile of actions, especially the rise in HDL-cholesterol levels induced by nicotinic acid, is unique among the currently available pharmacological tools to treat lipid disorders. Recently, a G-protein–coupled receptor, termed GPR109A (HM74A in humans, PUMA-G in mice), was described and shown to mediate the nicotinic acid–induced antilipolytic effects in adipocytes. One of the major problems of the pharmacotherapeutical use of nicotinic acid is a strong flushing response. This side effect, although harmless, strongly affects patient compliance. In the present study, we show that mice lacking PUMA-G did not show nicotinic acid–induced flushing. In addition, flushing in response to nicotinic acid was also abrogated in the absence of cyclooxygenase type 1, and mice lacking prostaglandin D2 (PGD2) and prostaglandin E2 (PGE2) receptors had reduced flushing responses. The mouse orthologue of GPR109A, PUMA-G, is highly expressed in macrophages and other immune cells, and transplantation of wild-type bone marrow into irradiated PUMA-G–deficient mice restored the nicotinic acid–induced flushing response. Our data clearly indicate that GPR109A mediates nicotinic acid–induced flushing and that this effect involves release of PGE2 and PGD2, most likely from immune cells of the skin. PMID:16322797

Benyó, Zoltán; Gille, Andreas; Kero, Jukka; Csiky, Marion; Suchánková, Marie Catherine; Nüsing, Rolf M.; Moers, Alexandra; Pfeffer, Klaus; Offermanns, Stefan

2005-01-01

145

The Ear Pages - Nobel Prize Educational Game  

NSDL National Science Digital Library

The 1961 Nobel Prize in Physiology or Medicine was awarded for the discovery of how sound is analyzed and communicated in the cochlea in the inner ear. Explore "The Ear Pages" and collect the snail shaped symbols of the cochlea to gain chances to answer a question correct in the quiz! (The cochlea works as a frequency/pitch analyzer in the inner ear.) You can choose between three levels of quizzes Â? beginner, advanced and expert. If you manage to get all the answers correct you will appear on the "High score of the week" list!

2009-01-01

146

Hearing: How Do Our Ears Work?  

NSDL National Science Digital Library

Students learn about the anatomy of the ear and how the ears work as a sound sensor. Ear anatomy parts and structures are explained in detail, as well as how sound is transmitted mechanically and then electrically through them to the brain. Students use LEGO® robots with sound sensors to measure sound intensities, learning how the NXT brick (computer) converts the intensity of sound measured by the sensor input into a number that transmits to a screen. They build on their experiences from the previous activities and establish a rich understanding of the sound sensor and its relationship to the TaskBot's computer.

2014-09-18

147

Gouty tophi on the ear: a review.  

PubMed

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

Chabra, Indy; Singh, Rajendra

2013-10-01

148

EARS: Electronic Access to Reference Service.  

PubMed

Electronic Access to Reference Service (EARS) is a front end to the Health Sciences Library's electronic mail system, with links to the online public catalog. EARS, which became operational in September 1984, is accessed by users at remote sites with either a terminal or microcomputer. It is menu-driven, allowing users to request: a computerized literature search, reference information, a photocopy of a journal article, or a book. This paper traces the history of EARS and discusses its use, its impact on library staff and services, and factors that influence the diffusion of new technology. PMID:3779167

Weise, F O; Borgendale, M

1986-10-01

149

Role of red meat and arachidonic acid in protein kinase C activation in rat colonic mucosa.  

PubMed

Two studies were conducted to investigate the role of meat and arachidonic acid in colonic signal transduction, particularly protein kinase C (PKC) activation. In Study 1, 26 male Wistar rats were fed a casein- or a beef-based diet for four weeks. PKC activity was measured from the proximal and distal colonic mucosa and diacylglycerol concentration from fecal samples. The beef diet significantly increased membrane PKC activity in the proximal and distal colon and cytosolic PKC in the distal colon. No differences were found in fecal diacylglycerol concentration for the rats maintained on the two diets. In Study 2, 57 male Wistar rats were divided into three dietary treatment groups: a control group, a group supplemented with arachidonic acid at 8 mg/day (an amount equivalent to that available from the beef diet in Study 1), and a group supplemented with fish oil at 166 mg/day. After a four-week supplementation period, 6 rats per group were used for colonic phospholipid fatty acid analysis and 13 rats per group were used for analysis of colonic prostaglandin E2 concentration, sphingomyelinase, and PKC activities. Supplementation of dietary arachidonic acid resulted in incorporation of arachidonic acid into colonic phosphatidylcholine, which was associated with an increase in mucosal prostaglandin E2 concentration compared with the fish oil group. However, arachidonate supplementation had no effect on sphingomyelinase or PKC activities. These data indicate that meat significantly increases colonic PKC activity, but this effect is probably not due to the arachidonic acid content of meat. PMID:9919617

Pajari, A M; Häkkänen, P; Duan, R D; Mutanen, M

1998-01-01

150

Chitosan-induced phospholipase A2 activation and arachidonic acid mobilization in P388D1 macrophages  

E-print Network

Chitosan-induced phospholipase A2 activation and arachidonic acid mobilization in P388D1 December 1999 Edited by Marco Baggiolini Abstract We have found that chitosan, a polysaccharide present in chitosan-induced arachidonate release revealed the involvement of the cytosolic Group IV phospholipase A2

Dennis, Edward A.

151

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

PubMed Central

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

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

1995-01-01

152

An analysis of the acoustic input impedance of the ear.  

PubMed

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

Withnell, Robert H; Gowdy, Lauren E

2013-10-01

153

PURDUE EXTENSIONArrested Ear Development in Hybrid Corn PURDUE EXTENSION  

E-print Network

1 PURDUE EXTENSIONArrested Ear Development in Hybrid Corn BP-85-W PURDUE EXTENSION D I S E A S E S O F C O R N Arrested Ear Development in Hybrid Corn www.btny.purdue.edu Arrested ear develop- ment to the abnormal corn ear development caused by a number of stress factors, including the application of nonionic

Holland, Jeffrey

154

Purdue extensionDiplodia Ear Rot Purdue extension  

E-print Network

1 Purdue extensionDiplodia Ear Rot BP-75-W Purdue extension d i s e a s e s o f c o r n Diplodia Ear Rot Authors: Charles Woloshuk Kiersten Wise www.btny.purdue.edu Diplodia ear rot, caused Diplodia ear rot. Hybrid susceptibility and weather also contribute to disease development. This bulletin

Holland, Jeffrey

155

Co-administration of acetyl-11-keto-beta-boswellic acid, a specific 5-lipoxygenase inhibitor, potentiates the protective effect of COX-2 inhibitors in kainic acid-induced neurotoxicity in mice.  

PubMed

Cyclooxygenase (COX) and lipoxygenase (LOX) are responsible for the metabolism of arachidonic acid into inflammatory metabolites, prostaglandins and leukotrienes, respectively. The upregulation of these enzymes in the central nervous system has been demonstrated to be responsible for the increased neuronal vulnerability to degeneration. Kainic acid, a glutamate receptor agonist and responsible for neuronal excitotoxicity and oxidative damage via different mechanisms, is capable of stimulating mRNA of both COX-2 and 5-LOX in the brain. The present study was designed to study the effects of COX inhibitors (indomethacin, nimesulide, rofecoxib) and a 5-LOX inhibitor (acetyl-11-keto-beta-boswellic acid; AKBA) and the combination of these inhibitors (dual inhibition) on kainic acid induced excitotoxicity and oxidative and nitrosative damage in mice. The results from the present study indicated that AKBA, indomethacin, and nimesulide per se did not produce any change in the behavioural parameters after kainic acid administration; however, rofecoxib per seproduced a significant increase in the latency of clonic (seizure-like) movement and a decrease in mortality rate as compared with kainic acid treated animals. In combination studies AKBA, rofecoxib, and nimesulide produced a more pronounced effect than either of these drugs alone. Further, the effect of AKBA combined with rofecoxib was significantly more marked when compared with AKBA combined with nimesulide. Besides this, identical results were found for the effect of these agents and their combination against oxidative damage induced by kainic acid. These findings indicate the potential role of COX-2 inhibitors and also their combination with the 5-LOX inhibitor in kainic acid induced excitotoxicity and oxidative damage by virtue of their antioxidant effect and suggest the need for the development of dual inhibitors for the treatment of neuronal excitotoxicity. PMID:17139192

Bishnoi, Mahendra; Patil, C S; Kumar, Anil; Kulkarni, Shrinivas K

2007-01-01

156

Technique Forms Working Inner Ear Cells  

MedlinePLUS

... cells in the inner ear detect head movements, gravity and sound. Researchers know the general scheme of ... Humans Gene Disruptions Associated with Autism Risk Computer Models Can Help Guide Ebola Response Diet Affects Autoinflammatory ...

157

Characterizing regeneration in the mammalian external ear  

PubMed Central

We have previously shown that MRL/MpJ mice have a capacity for regeneration instead of scar formation following an ear punch wound. Understanding the differences that occur between scar-free regeneration or repair with scarring will have great impact upon advances in skin tissue engineering. A key question that remains unanswered in the MRL/MpJ mouse model is whether regeneration was restricted to the ear or whether it extended to the skin. A histological analysis was conducted up to 4 months post-wounding, not only with 2-mm punch wounds to the ear but also to the skin on the backs of the same animals. MRL/MpJ mouse ear wounds regenerate faster than control strains, with enhanced blastema formation, a markedly thickened tip epithelium and reduced scarring. Interestingly, in the excisional back wounds, none of these regenerative features was observed and both the C57BL/6 control and MRL/MpJ mice healed with scarring. This review gives an insight into how this regenerative capacity may be due to evolutionary processes as well as ear anatomy. The ear is thin and surrounded on both sides by epithelia, and the dorsal skin is devoid of cartilage and under greater tensile strain. Analysis of apoptosis during ear regeneration is also discussed, assessing the role and expression of various members of the Bcl-2 family of proteins. Ongoing studies are focusing on de novo cartilage development in the regenerating ear, as well as understanding the role of downstream signalling cascades in the process. Identification of such signals could lead to their manipulation and use in a novel tissue-engineered skin substitute with scar-free integration. PMID:17005017

Metcalfe, Anthony D; Willis, Hayley; Beare, Alice; Ferguson, Mark W J

2006-01-01

158

Genetic Requirement for Pneumococcal Ear Infection  

PubMed Central

Background Ear infection or otitis media (OM) accounts for most bacterial respiratory infections in children in both developed and developing nations. Streptococcus pneumoniae, nontypeable Haemophilus influenzae, and Moraxella catarrhalis are the major OM pathogens. However, little is known about the genetic basis of bacterial OM largely due to practical difficulties in conducting research in ear infection models and genetically manipulating clinical isolates. Here, we report the first genome-scale in vivo screen for bacterial genes required for ear infection in a chinchilla model by signature tagged mutagenesis (STM), a high throughput mutant screen technique. Methodology/Principal Findings STM strains were constructed with a multi-drug resistant OM isolate ST556 (serotype 19F) and screened in a chinchilla OM model. Out of 5,280 mutants tested, 248 mutants were substantially underrepresented in the mutant pools recovered from the middle ear fluids of the infected chinchillas, indicating the impaired ability to survive and replicate in the middle ears due to genetic disruptions in the chromosome of strain ST556. Further DNA sequencing analysis mapped the mutations to 169 pneumococcal genes. Surprisingly, only 52 of these genes were required for pneumococcal nasopharyngeal colonization in a murine model. This infection site-specific gene requirement was verified by targeted mutagenesis in the selected genes. Conclusions/Significance These findings suggest that there are a subset of pneumococcal genes required for ear infection and that these may be distinct from those required for nasal colonization. Our data thus provide comprehensive gene targets for mechanistic understanding of pneumococcal ear infection. Finally, this study has also developed a model for future genome-scale search for virulence determinants in other pathogens associated with ear infections. PMID:18670623

Yang, Jun; O'Brien, Christopher J.; Lee, Scott L.; Mazurkiewicz, Joseph E.; Haataja, Sauli; Yan, Jing-Hua; Gao, George F.; Zhang, Jing-Ren

2008-01-01

159

Dermatologic diseases of the external ear.  

PubMed

The external ear is composed of the auricle (pinna) and the external auditory canal. Both of these structures contain elastic cartilage (except the earlobe) and a small amount of subcutaneous fat, which are covered by skin. The skin of the cartilaginous canal contains hair cells, sebaceous (lipid-producing) glands, and apocrine (ceruminous) glands; this is in contrast with the osseous canal, which contains neither glands nor hair follicles. The auricle is susceptible to environmental influences and trauma. Due to its exposed locale, the ear is particularly vulnerable to the effects of ultraviolet light and, consequently, to preneoplastic and neoplastic skin lesions. The ear also has a sound-receiving function and a location that is both visible and aesthetically obvious, thereby drawing considerable attention from the patient. Dermatologic diseases on the external ear are seen in a variety of medical disciplines. Dermatologists, otorhinolaryngologists, family practitioners, and general and plastic surgeons are regularly consulted about cutaneous lesions on the ear. These lesions can be grouped into three main categories: (1) infectious; (2) tumoral; and (3) noninfectious inflammatory. The purposes of this contribution are to review various dermatologic diseases of the external ear and to update current diagnosis and treatment information related to these conditions. PMID:24314388

Oztürkcan, Sedat; Oztürkcan, Serap

2014-01-01

160

Hemodynamic role of arachidonate 12- and 5-lipoxygenases in nephrotoxic serum nephritis.  

PubMed

The role of arachidonate 12- and 5-lipoxygenation eicosanoids in mediating acute changes in renal hemodynamics was assessed in nephrotoxic serum nephritis (NSN) in the rat. Following a single intravenous injection of nephrotoxic serum (NTS), significant decrements in glomerular filtration rate (GFR) and renal blood flow (RBF) occurred at one hour, and were associated with increments in glomerular polymorphonuclear leukocyte (PMN) counts and in the synthesis of thromboxane (Tx) B2, leukotriene (LT) B4 and 12-hydroxyeicosatetraenoic acid (12-HETE). Pretreatment of rats with the arachidonate 12-lipoxygenase inhibitor, baicalein, partially but significantly ameliorated the decrements in GFR and RBF, and blocked the enhanced glomerular synthesis of 12-HETE following administration of NTS. Likewise, pretreatment of rats with the arachidonate 5-lipoxygenase inhibitor, U-66858, partially ameliorated the decrements in GFR and RBF induced by NTS. Combined pretreatment of rats with baicalein and U-66858 ameliorated the decrements in GFR and RBF to an extent no different to that of U-66858 alone. In rats pretreated with the LTB4 receptor antagonist, U-75302, GFR and RBF remained depressed to levels no different than in animals which received NTS alone. These observations indicate that in NSN, the acute decrements in GFR and RBF are partially mediated by 12-HETE and arachidonate 5-lipoxygenation products. Leukotrienes other than LTB4, such as LTD4 and LTC4, are the likely candidates. PMID:8391096

Wu, S H; Bresnahan, B A; Lianos, E A

1993-06-01

161

Direct modulation of secretory chloride channels by arachidonic and other cis unsaturated fatty acids.  

PubMed Central

The effect of fatty acids on Cl- channels and transepithelial Cl- secretion is investigated. Patch-clamp experiments show that arachidonic acid blocks Cl- channels in a dose-dependent manner. Kinetic analysis shows that the mean open time is decreased 10-fold with 25 microM arachidonic acid. There is a linear relationship between the reciprocal of mean open time and blocker concentration within the range of 1 to 25 microM. The reciprocal of mean blocked time does not change with arachidonic acid concentration. Other cis unsaturated fatty acids, including oleic, linoleic, and ricinoleic acids, demonstrate similar blocks. Trans unsaturated acids such as elaidic acid and saturated fatty acids, including stearic, palmitic, and myristic acids, do not inhibit the channel at 20 microM. Ricinoleic acid decreases short circuit current in T84 cells, a colonic carcinoma cell line that secretes Cl-. Our results suggest that the direct effect of arachidonic and other fatty acids on Cl- secretion is to block Cl- channel current. PMID:1696009

Hwang, T C; Guggino, S E; Guggino, W B

1990-01-01

162

Antiplatelet effect of green tea catechins: a possible mechanism through arachidonic acid pathway  

Microsoft Academic Search

We have previously reported that green tea catechins (GTC) showed an antithrombotic activity, which might be due to antiplatelet effect rather than anticoagulation. The present study was performed to investigate the effect of GTC on the arachidonic acid (AA) metabolism in order to elucidate a possible antiplatelet mechanism. GTC inhibited the collagen-, AA- and U46619-induced rabbit platelet aggregation in vitro

Dong-Ju Son; Mi-Ra Cho; Yong-Ri Jin; Soo-Yeon Kim; Young-Hyun Park; Soo-Hwan Lee; Satoshi Akiba; Takashi Sato; Yeo-Pyo Yun

2004-01-01

163

CHRONIC ADMINISTRATION OF DOCOSAHEXAENOIC ACID OR EICOSAPENTAENOIC ACID, BUT NOT ARACHIDONIC ACID,  

E-print Network

, with UMP plus the omega-3 fatty acid docosa- hexaenoic acid (given by gavage), produces substantial in/or, by gavage, an omega-3 (docosahexae- noic or eicosapentaenoic acid) or omega-6 (arachidonic acid) fatty acid. Both of the omega-3 fatty acids elevated major brain phosphatide levels (by 18­28%, and 21­27%) and giv

Wurtman, Richard

164

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...

165

Hyperglycemia-induced teratogenesis is mediated by a functional deficiency of arachidonic acid.  

PubMed Central

Congenital malformations now represent the largest single cause of mortality in the infant of the diabetic mother. The mechanism by which diabetes exerts its teratogenic effects is not known. This study evaluated whether arachidonic acid might be involved, a possibility raised by the role of arachidonic acid in palatal elevation and fusion, processes analogous to neural tube folding and fusion. This hypothesis was tested in two animal models of diabetic embryopathy, the in vivo pregnant diabetic rat and the in vitro hyperglycemic mouse embryo culture. The subcutaneous injection of arachidonic acid (200-400 mg/kg per day) into pregnant diabetic rats during the period of organ differentiation (days 6-12) did not alter the maternal glucose concentration, the maternal weight gain, or the weight of the embryos. However, the incidence of neural tube fusion defects was reduced from 11% to 3.8% (P less than 0.005), the frequency of cleft palate was reduced from 11% to 4% (P less than 0.005), and the incidence of micrognathia was reduced from 7% to 0.8% (P less than 0.001). The addition of arachidonic acid to B10.A mouse embryos in culture also resulted in a reversal of hyperglycemia-induced teratogenesis. The teratogenic effect of D-glucose (8 mg/ml) in the medium resulted in normal neural tube fusion in only 32% of the embryos (P less than 0.006 when compared to controls). Arachidonic acid supplementation (1 or 10 micrograms/ml) produced a rate of neural tube fusion (67%) that was not significantly different from that observed in controls. The evidence presented indicates that arachidonic acid supplementation exerts a significant protective effect against the teratogenic action of hyperglycemia in both in vivo (rat) and in vitro (mouse) animal models. These data therefore suggest that the mechanism mediating the teratogenic effect of an increased glucose concentration involves a functional deficiency of arachidonic acid at a critical stage of organogenesis. Images PMID:3934670

Goldman, A S; Baker, L; Piddington, R; Marx, B; Herold, R; Egler, J

1985-01-01

166

Cinnamtannin D-1 protects pancreatic ?-cells from palmitic acid-induced apoptosis by attenuating oxidative stress.  

PubMed

In previous studies, A-type procyanidin oligomers isolated from Cinnamomum tamala were proved to possess antidiabetic effect and protect pancreatic ?-cells in vivo. The aim of this study was to unveil the mechanisms of protecting pancreatic ?-cells from palmitic acid-induced apoptosis by cinnamtannin D-1 (CD1), one of the main A-type procyanidin oligomers in C. tamala. CD1 was discovered to dose-dependently reduce palmitic acid- or H2O2-induced apoptosis and oxidative stress in INS-1 cells, MIN6 cells, and primary cultured murine islets. Moreover, CD1 could reverse palmitic acid-induced dysfunction of glucose-stimulated insulin secretion in primary cultured islets. These results indicate that reduction of apoptosis and oxidative stress might account for the protection effect of CD1, which provided a better understanding of the mechanisms of the antidiabetic effects of procyanidin oligomers. PMID:24815044

Wang, Ting; Sun, Peng; Chen, Liang; Huang, Qi; Chen, Kaixian; Jia, Qi; Li, Yiming; Wang, Heyao

2014-06-01

167

Endothelin receptors in kainic acid-induced neural lesions of rat brain  

Microsoft Academic Search

Seven days after an intracerebroventricular injection of 0.8?g kainic acid, a time of neural tissue-repair after damage, we applied our receptor autoradiographic method to examine changes in the endothelin receptors in kainic acid-induced neural lesions of the rat brain. There were belt-shaped areas with the de novo expressed [125I]endothelin-1 binding sites in the damaged hippocampus CA1, CA3, and CA4 subfields.

Y. Sakurai-Yamashita; M. Niwa; K. Yamashita; Y. Kataoka; A. Himeno; K. Shigematsu; K. Tsutsumi; K. Taniyama

1997-01-01

168

Acid-induced gelation of natural actomyosin from Atlantic cod ( Gadus morhua) and burbot ( Lota lota)  

Microsoft Academic Search

The acid-induced gelation of natural actomyosin (NAM) from burbot (Lota lota) and Atlantic cod (Gardus morhua) added with d-gluconic acid-?-lactone (GDL) during incubation at room temperature (22–23°C) for 48h was investigated. During acidification, pH values of both NAMs reached 4.6 within 48h. Both NAMs underwent aggregation during acidification as evidenced by increases in turbidity and particle size, especially after 6h

Siriporn Riebroy; Soottawat Benjakul; Wonnop Visessanguan; Ulf Erikson; Turid Rustad

2009-01-01

169

[Passive and active middle ear implants].  

PubMed

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:19353457

Beutner, D; Hüttenbrink, K B

2009-05-01

170

Ear Acupuncture in European Traditional Medicine  

PubMed Central

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

Firenzuoli, Fabio

2007-01-01

171

Assessment of Ear Disorders Using Power Reflectance  

PubMed Central

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

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

2013-01-01

172

Passive and active middle ear implants  

PubMed Central

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

Beutner, Dirk; Hüttenbrink, Karl-Bernd

2011-01-01

173

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...

174

Endoscopic anatomy of the pediatric middle ear.  

PubMed

Traditionally, otologists have aimed to produce a clean, dry, safe ear with the best possible hearing result. More recently, "less invasively" has been added to this list of goals. The development of small-diameter, high-quality rigid endoscopes and high-definition video systems has made totally endoscopic, transcanal surgery a reality in adult otology and a possibility in pediatric otology. This article reviews the anatomy of the pediatric middle ear and its surrounding airspaces and structures based on the work of dozens of researchers over the past 50 years. It will focus on the developmental changes in ear anatomy from birth through the first decade, when structure and function change most rapidly. Understanding the limits and possibilities afforded by new endoscopic technologies, the pediatric otologist can strive for results matching or exceeding those achieved by more invasive surgical approaches. PMID:24154745

Isaacson, Glenn

2014-01-01

175

Ear lobule reconstruction using nasal septal cartilage.  

PubMed

Surgical reconstruction of an earlobe requires adequate support without sacrificing the delicacy necessary for an attractive result. A two-stage ear lobule reconstruction using a mastoid skin pocket and cartilage from the nasal septum was performed in six patients. The earlobe aesthetics were acceptable and allowed ear piercing. There were no major complications, including no loss of flap, graft extrusion, septal perforation, or infection. Range of follow-up was 1 to 6 years, with an average of 3 years. No revisions have been performed. A two-stage technique for ear lobule reconstruction is described using septal cartilage to preserve shape and definition that has the additional advantage of minimal morbidity. PMID:23542248

Bastidas, Nicholas; Jacobs, Jordan M S; Thorne, Charles H

2013-04-01

176

Middle ear cholesteatoma in 11 dogs.  

PubMed

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

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

2011-06-01

177

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

SciTech Connect

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.

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

1986-01-20

178

Middle Ear Infection (Chronic Otitis Media) and Hearing Loss  

MedlinePLUS

Middle Ear Infection (Chronic Otitis Media) and Hearing Loss Middle Ear Infection (Chronic Otitis Media) and Hearing Loss Patient Health Information News media interested in covering the latest from AAO-HNS/F can find ...

179

Transmission matrix analysis of the chinchilla middle ear  

PubMed Central

Despite the common use of the chinchilla as an animal model in auditory research, a complete characterization of the chinchilla middle ear using transmission matrix analysis has not been performed. In this paper we describe measurements of middle-ear input admittance and stapes velocity in ears with the middle-ear cavity opened under three conditions: intact tympano-ossicular system and cochlea, after the cochlea has been drained, and after the stapes has been fixed. These measurements, made with stimulus frequencies of 100–8000 Hz, are used to define the transmission matrix parameters of the middle ear and to calculate the cochlear input impedance as well as the middle-ear output impedance. This transmission characterization of the chinchilla middle ear will be useful for modeling auditory sensitivity in the normal and pathological chinchilla ear. PMID:17672642

Songer, Jocelyn E.; Rosowski, John J.

2008-01-01

180

Shaping Magnetic Fields to Direct Therapy to Ears  

E-print Network

delivery, ear, eye, nanotherapy, stem cells Abstract Magnetic fields have the potential to noninvasively cells--in blood, through tissue, and across barriers--to disease locations. In this article, we consider . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 456 2. DRUG DELIVERY TO THE INNER EAR

Shapiro, Benjamin

181

Modeling Ear-Canal Acoustics, Incorporating Visco-Thermal Effects and the Influence of the Middle Ear  

NASA Astrophysics Data System (ADS)

The ear canal, below about 6 kHz, is well described by a uniform cylinder (sound propagates predominantly as plane waves) with the middle ear being a non-rigid termination. A non-rigid termination can be viewed as altering, as a function of frequency, the acoustic length and radius of the cylinder. It is generally assumed that sound transmission in the ear canal over this frequency range is lossless. This paper presents a method for calculating the influence of visco-thermal losses and the middle ear on ear canal acoustics. The acoustic input impedance was derived from sound pressure measurements in the ear canal and then a nonlinear least-square-fit to the data with a one-dimensional model incorporating visco-thermal losses generated length, radius, and middle ear impedance parameters. It was found that a rigid wall assumption for visco-thermal calculations was insufficient to account for damping in the ear canal. The properties of the ear canal wall (not being a rigid, low-friction surface), incorporated into visco-thermal losses as a scaling factor, provided a better fit to the data. Viscous and thermal losses were both found to affect sound propagation in the ear canal, viscous losses being more significant, altering the acoustic input impedance of the ear primarily in the region of the standing wave frequency. The model data suggests that the middle ear influences ear canal acoustics up to about 3 kHz.

Gowdy, Lauren E.; Withnell, Robert H.

2011-11-01

182

Nitric oxide responsible for NMDA receptor-evoked inhibition of arachidonic acid incorporation into lipids of brain membrane  

Microsoft Academic Search

The activation of the glutamatergic NMDA receptor has no effect on arachidonic acid release from cortical synaptoneurosomal\\u000a lipids prelabeled with [1-14C]arachidonic acid ([14C]AA). However, activation of NMDA receptor leads to the reduction of AA incorporation into rat brain cortex synaptoneurosomal\\u000a membrane phosphatidylinositol (PI). The competitive NMDA receptor antagonist, 2-amino-5-phosphovaleric acid (APV), completely\\u000a eliminates the effect of NMDA on this process.

Marek Samochocki; Malgorzata Chalimoniuk; Joanna Strosznajder

1996-01-01

183

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

PubMed Central

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

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

2014-01-01

184

Ca2+ Signaling in the Inner Ear  

NSDL National Science Digital Library

The inner ear contains delicate sensory receptors that have adapted to detect the minutest mechanical disturbances. Ca2+ ions are implicated in all steps of the transduction process, as well as in its regulation by an impressive ensemble of finely tuned feedback control mechanisms. Recent studies have unveiled some of the key players, but things do not sound quite right yet.

2007-04-01

185

livious ear ie Michael J. Kearns  

E-print Network

livious ear ie Michael J. Kearns AT&T Bell Laboratories 600 Mountain Avenue, Room 2A-423 Murray different target concept f. Each run results in the ad- dition of a new hypothesis representation r to effectively support in- clusion tests between any pair of target concepts. More precisely, given any ri and r2

Kearns, Michael

186

Collagen types in the middle ear mucosa  

Microsoft Academic Search

The distribution of various collagen types — in particular that of type 11 as the major collagen in cartilage — in normal auricular structures is discussed with reference to a 1994 report by Ovesen describing the presence of collagen type II in normal middle ear mucosa. In contrast to this report, no collagen type 11 is normally found in the

A. G. Nerlich

1995-01-01

187

The fungal flora of zoo animals' ears.  

PubMed

The mycotic flora of the ears of zoo animals was investigated in a large zoological garden in Germany. Malassezia pachydermatis was isolated from the following animals: big ant-eater, brown bear, common wombat, Eurasian badger, Indian elephant, Mangaliza pig and wide-mouthed rhinoceros. Aspergillus and Penicillium species, yeasts and zygomycetes were also isolated from some animals. PMID:7935595

Kuttin, E S; Müller, J

1994-01-01

188

Getting Teens to Read with Their Ears  

ERIC Educational Resources Information Center

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…

Fues, Marianne Cole

2009-01-01

189

Keep Your Ear-Lids Open.  

ERIC Educational Resources Information Center

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

Ferrington, Gary

1994-01-01

190

Ear biometric recognition using local texture descriptors  

NASA Astrophysics Data System (ADS)

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.

Benzaoui, Amir; Hadid, Abdenour; Boukrouche, Abdelhani

2014-09-01

191

Lysophosphatidylcholine induces arachidonic acid release and calcium overload in cardiac myoblastic H9c2 cells  

Microsoft Academic Search

Lysophosphatidylcholine (lyso-PC) and arachido- nate are products of phosphatidylcholine hydrolysis by phospholipase A 2 . In this study, the modulation of arachido- nate release by exogenous lyso-PC in rat heart myoblastic H9c2 cells was examined. Incubation of H9c2 cells with lyso-PC resulted in an enhanced release of arachidonate in both a time- and dose-dependent fashion. Lyso-PC species containing palmitoyl (C

Leonard S. Golfman; Norman J. Haughey; Jason T. Wong; Jenny Y. Jiang; Douglas Lee; Jonathan D. Geiger; Patrick C. Choy

192

Assessment of the arachidonic acid content in foods commonly consumed in the American diet  

Microsoft Academic Search

Arachidonic acid (AA) is an extremely important fatty acid involved in cell regulation. When provided in the diet, it is cogently\\u000a incorporated in membrane phospholipids and enhances eicosanoid biosynthesis in vivo and in vitro; however, controversy exists as to the levels of AA in food and in the diet. This study determined the amount of AA in cooked\\u000a and raw

Laura Taber; Chun-Hung Chiu; Jay Whelan

1998-01-01

193

Mediation of renal vascular effects of epidermal growth factor by arachidonate metabolites.  

PubMed

In the rat, intrarenal infusion of epidermal growth factor decreases renal blood flow and glomerular filtration rate, and epidermal growth factor (EGF) induces contraction of cultured rat mesangial cells. The present studies examined the role of arachidonic acid metabolites in this response. Intrarenal EGF infusion increased urinary iPGF2 alpha by 300%, and in isolated glomeruli EGF stimulated iPGF2 alpha by 38%, but did not affect thromboxane B2 production. Furthermore, the thromboxane A2 receptor antagonist, SQ29548, did not block EGF's vasoconstrictive effects. After selective cyclooxygenase inhibition with ibuprofen, intrarenal EGF infusion no longer produced local vasoconstriction but instead led to systemic vasodilation (SBP: 117 +/- 10 vs. 98 +/- 7; n = 5; P less than 0.05) that was accompanied by significant increases in RPF (3.8 +/- 0.4 vs. 5.6 +/- 0.2; P less than 0.01) and glomerular filtration rate (0.9 +/- 0.1 vs. 1.1 +/- 0.1; P less than 0.05). When total arachidonate metabolism was inhibited by the additional administration of 5,8,11,14-eicosatetraynoic acid, the EGF-induced vasodilation observed during cyclooxygenase inhibition alone was abolished, and vasoconstrictor responses to EGF were again noted. Similar effects were noted with concomitant administration of the c-P450 inhibitor ketoconazole. EGF's vasoconstrictive effects were unaltered by the simultaneous administration of the angiotensin II antagonist saralasin. Thus, the renal hemodynamic responses to EGF are mediated in part by arachidonic acid metabolites. Cyclooxygenase inhibition unmasks a potent renal and systemic vasodilator action of EGF owing to its stimulation of systemic release of noncyclooxygenase arachidonate metabolites. PMID:2138579

Harris, R C; Munger, K A; Badr, K F; Takahashi, K

1990-04-01

194

Protective Effect of Arachidonic Acid on Glutamate Neurotoxicity in Rat Retinal Ganglion Cells  

Microsoft Academic Search

PURPOSE. Low concentrations of excitotoxic agents such as glutamate decrease survival of retinal ganglion cells (RGCs) and may be an important cause of RGC death in a variety of retinal diseases. Arachidonic acid (AA), an intercellular messenger in the central nervous system, has been reported to have multiple effects on glutamate receptors, including an inhibitory effect on non-N-methyl-D-aspartate (NMDA) receptors.

Atsushi Kawasaki; Ming-Hu Han; Ji-Ye Wei; Keiji Hirata; Yasumasa Otori; Colin J. Barnstable

2002-01-01

195

Arachidonic acid-derived oxidation products initiate apoptosis in vascular smooth muscle cells  

Microsoft Academic Search

The mechanism of arachidonic acid (AA)-induced apoptosis in vascular smooth muscle cells (VSMCs) was studied in the A-10 rat aortic smooth muscle cell line. Treatment of serum-deprived VSMCs with 50?M AA for 24h resulted in a loss of cell viability. The apoptotic effect of AA was characterized by annexin V binding, sub-G1 population of cells, cell shrinkage and chromatin condensation.

Shailaja Kalyankrishna; Jean-Hugues Parmentier; Kafait U Malik

2002-01-01

196

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

PubMed Central

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

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

2008-01-01

197

Comparative evaluation of arachidonic acid (AA)- and tetradecanoylphorbol acetate (TPA)-induced dermal inflammation  

Microsoft Academic Search

The effects of topical application of arachidonic acid (AA) or phorbol ester, tetradecanoylphorbol 13-acetate (TPA), on edema response, vascular permeability, MPO, NAG, and generation of eicosanoids were studied in two murine models of cutaneous inflammation. AA produced a short-lived edema response with a rapid onset that was associated with marked increases in levels of prostaglandins (PGE2, 6-keto-PGF1a, PGF2a), thromboxane B2

Tadimeti S. Rao; Jerry L. Currie; Alexander F. Shaffer; Peter C. Isakson

1993-01-01

198

Conjugated linoleic acid reduces arachidonic acid content and PGE 2 synthesis in murine keratinocytes  

Microsoft Academic Search

Dietary conjugated linoleic acid (CLA) is associated with decreased 12-O-tetradecanoyl-phorbol-13-acetate (TPA)-induced tumor promotion in mouse skin. In addition, CLA decreases TPA-induced prostaglandin E synthesis and ornithine decarboxylase activity in cultured keratinocytes compared with linoleic acid (LA) and arachidonic acid (AA). When LA or CLA was added to keratinocyte cell cultures, the amounts of each of these cellular fatty acids increased

Kai-Li Liu; Martha A Belury

1998-01-01

199

Arachidonic acid reduces the stress response of gilthead seabream Sparus aurata L  

Microsoft Academic Search

In this study the influence of the dietary level of the fatty acid arachidonic acid (ArA, 20:4n-6) was determined on the acute stress response and osmoregulation of adult gilthead seabream Sparus aurata L. Seabream were fed a diet containing either 0.9% or 2.4% of total fatty acids as ArA for 18 days before being subjected to a 5 min period

R. D. van Anholt; E. A. T. Spanings; W. M. Koven; O. Nixon; S. E. Wendelaar Bonga

2004-01-01

200

A new dual inhibitor of arachidonate metabolism isolated from Helichrysum italicum  

Microsoft Academic Search

Six acetophenones (1–6) and one ?-pyrone (7), previously isolated from Helichrysum italicum, were tested for their ability to inhibit enzymatic and non-enzymatic lipid peroxidation, the stable 1,1-diphenyl-2-pycryl-hydrazyl free radical, superoxide scavenging and arachidonic acid metabolism. In addition, they were studied in different experimental models such as the chronic inflammation induced by 12-O-tetradecanoylphorbol 13-acetate (TPA), the phospholipase A2-induced mouse paw oedema

Araceli Sala; M. Carmen Recio; Guillermo R. Schinella; Salvador Máñez; Rosa M. Giner; José-Luis R??os

2003-01-01

201

Vibrational structure of the polyunsaturated fatty acids eicosapentaenoic acid and arachidonic acid studied by infrared spectroscopy  

Microsoft Academic Search

The spectroscopic discrimination of the two structurally similar polyunsaturated C20 fatty acids (PUFAs) 5,8,11,14,17-eicosapentaenoic acid and 5,8,11,14-eicosatetraenoic acid (arachidonic acid) is shown. For this purpose their vibrational structures are studied by means of attenuated total reflection (ATR) Fourier-transform infrared (FT-IR) spectroscopy. The fingerprint regions of the recorded spectra are found to be almost identical, while the C–H stretching mode regions

Johannes Kiefer; Kristina Noack; Juergen Bartelmess; Christian Walter; Heike Dörnenburg; Alfred Leipertz

2010-01-01

202

Stimulus-specific induction of phospholipid and arachidonic acid metabolism in human neutrophils  

Microsoft Academic Search

Phospholipid remodeling resulting in arachidonic acid (AA) release and metabolism in human neutrophils stimulated by calcium ionophore A23187 has been extensively studied, while data obtained using physiologically relevant stimuli is limited. Opsonized zymosan and immune complexes induced stimulus-specific alterations in lipid metabolism that were different from those induced by A23187. (³H)AA release correlated with activation of phospholipase A2 (PLA2) but

Richard W. Godfrey; Rosalie M. Manzi; Mike A. Clark; Sylvia T. Hoffstein

1987-01-01

203

Immunohistochemical Localization of Key Arachidonic Acid Metabolism Enzymes during Fracture Healing in Mice  

PubMed Central

This study investigated the localization of critical enzymes involved in arachidonic acid metabolism during the initial and regenerative phases of mouse femur fracture healing. Previous studies found that loss of cyclooxygenase-2 activity impairs fracture healing while loss of 5-lipoxygenase activity accelerates healing. These diametric results show that arachidonic acid metabolism has an essential function during fracture healing. To better understand the function of arachidonic acid metabolism during fracture healing, expression of cyclooxygenase-1 (COX-1), cyclooxygenase -2 (COX-2), 5-lipoxygenase (5-LO), and leukotriene A4 hydrolase (LTA4H) was localized by immunohistochemistry in time-staged fracture callus specimens. All four enzymes were detected in leukocytes present in the bone marrow and attending inflammatory response that accompanied the fracture. In the tissues surrounding the fracture site, the proportion of leukocytes expressing COX-1, COX-2, or LTA4H decreased while those expressing 5-LO remained high at 4 and 7 days after fracture. This may indicate an inflammation resolution function for 5-LO during fracture healing. Only COX-1 was consistently detected in fracture callus osteoblasts during the later stages of healing (day 14 after fracture). In contrast, callus chondrocytes expressed all four enzymes, though 5-LO appeared to be preferentially expressed in newly differentiated chondrocytes. Most interestingly, osteoclasts consistently and strongly expressed COX-2. In addition to bone surfaces and the growth plate, COX-2 expressing osteoclasts were localized at the chondro-osseous junction of the fracture callus. These observations suggest that arachidonic acid mediated signaling from callus chondrocytes or from callus osteoclasts at the chondro-osseous junction regulate fracture healing. PMID:24516658

Lin, Hsuan-Ni; O’Connor, J. Patrick

2014-01-01

204

Sources of Variability in Reflectance Measurements on Normal Cadaver Ears  

Microsoft Academic Search

Objectives: The development of acoustic reflectance measurements may lead to noninvasive tests that provide information currently unavailable from standard audiometric testing. One factor limiting the development of these tests is that normal-hear- ing human ears show substantial intersubject vari- ations. This work examines intersubject variability that results from measurement location within the ear canal, estimates of ear-canal area, and varia-

Susan E. Voss; Nicholas J. Horton; Rebecca R. Woodbury; Kathryn N. Sheffield

2008-01-01

205

Ear and kidney syndromes: Molecular versus clinical approach  

Microsoft Academic Search

Ear and kidney syndromes: Molecular versus clinical approach.The association between ear and kidney anomalies is not usually due to an insult to the embryo. In recent years, many essential development control genes that coordinate the assembly and function of kidney and ear have been discovered through the generation of animal mutants and have increased our understanding of the mechanisms of

HASSANE IZZEDINE; FREDERIC TANKERE; VINCENT LAUNAY-VACHER; GILBERT DERAY

2004-01-01

206

A Survey on Ear Biometrics AYMAN ABAZA, WVHTC Foundation  

E-print Network

22 A Survey on Ear Biometrics AYMAN ABAZA, WVHTC Foundation ARUN ROSS, West Virginia University Recognizing people by their ear has recently received significant attention in the literature. Several reasons account for this trend: first, ear recognition does not suffer from some problems associated with other

Ross, Arun Abraham

207

Understanding Inner Ear Development with Gene Expression Profiling  

E-print Network

Understanding Inner Ear Development with Gene Expression Profiling Zheng-Yi Chen,1,2 David P. Corey, Maryland 20815 ABSTRACT: Understanding the development of the inner ear requires knowing the spatial-tissue comparisons will identify genes unique to the inner ear, which will expe- dite the identification of new

Corey, David P.

208

History of Studies on Mammalian Middle Ear Evolution: A  

E-print Network

History of Studies on Mammalian Middle Ear Evolution: A Comparative Morphological and Developmental for Developmental Biology, RIKEN, Kobe, Japan The mammalian middle ear represents one of the most fundamental middle ear was derived from elements of the jaw joint of nonmammalian amniotes. Fossils of mammalian

Sullivan, Jack

209

Ear growth, developmental stages and yield in winter wheat  

E-print Network

Ear growth, developmental stages and yield in winter wheat Jean-François LEDENT Volkmar STOY Helena in length (R,) of ear primordia was measured in collections of winter wheats (Triticum aestivum (L.) em or morphological characters. However, genotypes with faster growing ear primordia tended to have smaller cars

Paris-Sud XI, Université de

210

Short Papers___________________________________________________________________________________________________ Comparison and Combination of Ear and Face  

E-print Network

that the ear may have advantages over the face for biometric recognition. Our previous experiments with ear and face recognition, using the standard principal component analysis approach, showed lower recognition rigorously controlled for relative quality of face and ear images. We find that recognition performance

Bowyer, Kevin W.

211

21 CFR 874.3430 - Middle ear mold.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food and...Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is...

2012-04-01

212

21 CFR 874.3430 - Middle ear mold.  

...2014-04-01 2014-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food and...Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is...

2014-04-01

213

21 CFR 874.3430 - Middle ear mold.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food and...Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is...

2013-04-01

214

21 CFR 874.3430 - Middle ear mold.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food and...Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is...

2011-04-01

215

21 CFR 874.3430 - Middle ear mold.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Middle ear mold. 874.3430 Section 874.3430 Food and...Prosthetic Devices § 874.3430 Middle ear mold. (a) Identification. A middle ear mold is a preformed device that is...

2010-04-01

216

The ear and its malformations: strange beliefs and misconceptions  

Microsoft Academic Search

Objective. To explore the strange beliefs and misconceptions related to the ear and its malformations, and how these have changed from ancient times until today.Methods. Ancient documents, journal articles, and history books were studied to research ancient and current beliefs and misconceptions with regard to the ear and its malformations.Results. The ear has been the centre of various beliefs and

Irene E Gamatsi; Thomas P Nikolopoulos; Dimitra E Lioumi

2003-01-01

217

A pilot randomized controlled trial comparing bismuth iodine paraffin paste external ear pack and no ear pack after middle ear surgery.  

PubMed

To pilot a substantive randomized control trial comparing post-operative external ear canal pack with no ear pack after middle ear surgery, 32 adults undergoing primary posterior bony canal wall preserving middle ear surgery were randomized to have either a bismuth iodoform paraffin paste pack or no ear pack post-operatively. Outcome measures included clinician- and patient-recorded visual analogue scale scores for ear signs and symptoms at 3 weeks and 3 months and audiometric findings at 3 months post-operatively. There was no statistically significant inter-group difference in 3-week clinician and patient cumulative scores for ear signs and symptoms. There was also no significant difference in graft take rate, appearance of ear canals and audiometric results in either group at 3 months. No difference in ear symptoms, clinician findings or hearing was demonstrated between patients with a post-operative pack compared to those without a pack following middle ear surgery in this pilot study. PMID:24337896

Javed, Faisal; Whitwell, Russell; Hajioff, Daniel; Robinson, Philip; Rea, David; Macleod, Iain; White, Paul; Nunez, Desmond A

2013-12-14

218

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

PubMed Central

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

Mesaros, Clementina; Blair, Ian A.

2012-01-01

219

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

SciTech Connect

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.

Radogna, F. [Dipartimento di Biologia, Universita di Roma Tor Vergata, via Ricerca Scientifica, 1 00133 Roma (Italy); Sestili, P.; Martinelli, C.; Paolillo, M. [Istituto di Ricerca sull'Attivita Motoria (Italy); Paternoster, L.; Albertini, M.C.; Accorsi, A. [Istituto di Chimica Biologica, Universita di Urbino Carlo Bo (Italy); Gualandi, G. [DABAC, Universita della Tuscia (Italy); Ghibelli, L. [Dipartimento di Biologia, Universita di Roma Tor Vergata, via Ricerca Scientifica, 1 00133 Roma (Italy)], E-mail: ghibelli@uniroma2.it

2009-07-15

220

Stimulated arachidonate metabolism during foam cell transformation of mouse peritoneal macrophages with oxidized low density lipoprotein.  

PubMed Central

Changes in arachidonate metabolism were examined in mouse peritoneal macrophages incubated with various types of lipoproteins. Oxidized low density lipoprotein (LDL) was incorporated by macrophages and stimulated macrophage prostaglandin E2 (PGE2) and leukotriene C4 syntheses, respectively, 10.8- and 10.7-fold higher than by the control. Production of 6-keto-PGF1 alpha, a stable metabolite of prostacyclin, was also stimulated. No stimulation was found with native LDL, which was minimally incorporated by the cells. Acetylated LDL and beta-migrating very low density lipoprotein (beta-VLDL), though incorporated more efficiently than oxidized LDL, also had no stimulatory effect. When oxidized LDL was separated into the lipoprotein-lipid peroxide complex and free lipid peroxides, most of the stimulatory activity was found in the former fraction, indicating that stimulation of arachidonate metabolism in the cell is associated with uptake of the lipoprotein-lipid peroxide complex. These results suggest that peroxidative modification of LDL could contribute to the progression of atheroma by stimulating arachidonate metabolism during incorporation into macrophages. Images PMID:3125226

Yokode, M; Kita, T; Kikawa, Y; Ogorochi, T; Narumiya, S; Kawai, C

1988-01-01

221

Stimulation of arachidonic acid metabolism by different types of tumor promoters.  

PubMed

Skin tumor-promoting agents, including the 12-O-tetradecanoylphorbol-13-acetate (TPA)-type tumor promoters, such as diterpine phorbol esters, teleocidin and aplysiatoxin, and a non-TPA-type tumor promoter (the newly described palytoxin, present in the coelenterate of the genus Palythoa), stimulated arachidonic acid metabolism by rat liver cells in culture. Palytoxin was 1000-3000 times more effective than TPA-type tumor promoters. The stimulations of arachidonic acid metabolism by palytoxin and the TPA-type tumor promoters were synergistic, whereas the stimulations among the TPA-type tumor promoters were not. The stimulation of arachidonic acid metabolism by palytoxin was synergistic with that of epidermal growth factor (EGF), transforming growth factor-alpha (TGF-alpha) and transforming growth factor-beta (TGF-beta). An antiserum to the EGF-receptor that blocks EGF binding partially inhibited the synergistic responses to palytoxin and EGF and palytoxin and TGF-alpha, whereas an antiserum to the EGF-receptor that does not block EGF binding or a non-immune rabbit serum did not. PMID:2865014

Levine, L; Fujiki, H

1985-11-01

222

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

PubMed

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 ?B (NF-?B) 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

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

2015-02-01

223

Urotensin-II Induces Ear Flushing in Rats  

PubMed Central

Background and purpose: While investigating the effects of systemic urotensin II (U-II), a potent vasoactive peptide acting at the UT receptor, we observed ear pinna flushing after systemic administration to conscious rats. In the present study, U-II-induced ear flushing was quantified in terms of ear pinna temperature change and potential mechanisms were explored. Experimental approach: U-II-induced ear flushing was quantified by measuring lateral ear pinna temperature changes and compared to that of calcitonin gene-related peptide (CGRP), a known cutaneous vasodilator. Further, the effects of a variety of pharmacological agents on U-II-induced ear flushing were explored. Key results: Subcutaneous injection of U-II (9 ?g kg?1)produced localized ear pinna flushing with an onset of ?15?min, a duration of ?30?min and a maximal temperature change of 9°C. In contrast, CGRP caused cutaneous flushing within multiple cutaneous beds including the ear pinna with a shorter onset and greater duration than U-II. A potent UT receptor antagonist, urantide, blocked U-II-induced ear flushing but did not affect CGRP-induced ear flushing. Pretreatment with indomethacin or L-N ? -nitroarginine methylester (L-NAME) abolished U-II-induced ear flushing. Mecamylamine or propranolol did not affect this response to U-II. Direct intracerebroventricular injection studies suggested that the ear flushing response to U-II was not mediated directly by the CNS. Conclusion and implications: Our results suggest that U-II-induced ear flushing and temperature increase is mediated by peripheral activation of the UT receptor and involves prostaglandin- and nitric oxide-mediated vasodilation of small capillary beds in the rat ear pinna. PMID:17211454

Qi, J-S; Schulingkamp, R; Parry, T J; Colburn, R; Stone, D; Haertlein, B; Minor, L K; Andrade-Gordon, P; Damiano, B P

2007-01-01

224

Mouse Middle Ear Ion Homeostasis Channels and Intercellular Junctions  

PubMed Central

Hypothesis The middle ear contains homeostatic mechanisms that control the movement of ions and fluids similar to those present in the inner ear, and are altered during inflammation. Background The normal middle ear cavity is fluid-free and air-filled to allow for effective sound transmission. Within the inner ear, the regulation of fluid and ion movement is essential for normal auditory and vestibular function. The same ion and fluid channels active in the inner ear may have similar roles with fluid regulation in the middle ear. Methods Middle and inner ears from BALB/c mice were processed for immunohistochemistry of 10 specific ion homeostasis factors to determine if similar transport and barrier mechanisms are present in the tympanic cavity. Examination also was made of BALB/c mice middle ears after transtympanic injection with heat-killed Haemophilus influenza to determine if these channels are impacted by inflammation. Results The most prominent ion channels in the middle ear included aquaporins 1, 4 and 5, claudin 3, ENaC and Na+,K+-ATPase. Moderate staining was found for GJB2, KCNJ10 and KCNQ1. The inflamed middle ear epithelium showed increased staining due to expected cellular hypertrophy. Localization of ion channels was preserved within the inflamed middle ear epithelium. Conclusions The middle ear epithelium is a dynamic environment with intrinsic mechanisms for the control of ion and water transport to keep the middle ear clear of fluids. Compromise of these processes during middle ear disease may underlie the accumulation of effusions and suggests they may be a therapeutic target for effusion control. PMID:22720014

Morris, Lisa M.; DeGagne, Jacqueline M.; Kempton, J. Beth; Hausman, Frances; Trune, Dennis R.

2012-01-01

225

Diseases of the middle ear in childhood  

PubMed Central

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

Minovi, Amir; Dazert, Stefan

2014-01-01

226

The inner ear and the neurologist  

PubMed Central

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

Agrup, Charlotte; Gleeson, Michael; Rudge, Peter

2007-01-01

227

A Rare Case of Petrified Ear  

PubMed Central

Calcification or ossification of the auricle, also referred to as petrified ear, is a rare diagnosis in dermatology. In medical literature, it has most often been attributed to trauma, hypothermia and frostbite, or hypercalcemia secondary to a metabolic or endocrine disorder, such as Addison's disease. Here, we report the clinical and radiologic findings of a 79-year-old African American male whose unilateral petrified auricle was an incidental finding. He had a preceding history of hyperparathyroidism and subsequent hypercalcemia treated with a subtotal parathyroidectomy three years prior to presentation. In addition to laboratory analysis, a history and physical examination was performed which revealed no other signs of hypercalcemia. Radiologic studies demonstrated partial ossification of the external auricular cartilage on the left side. The patient was diagnosed with the rare occurrence of a petrified ear. In light of this case, we provide a discussion concerning the possible etiologies of this diagnosis including appropriate patient evaluation and possible treatment recommendations. PMID:23259082

Buikema, Kathryn E.; Adams, Erin G.

2012-01-01

228

Scaling of the mammalian middle ear.  

PubMed

This study considers the general question how animal size limits the size and information receiving capacity of sense organs. To clarify this in the case of the mammalian middle ear, I studied 63 mammalian species, ranging from a small bat to the Indian elephant. I determined the skull mass and the masses of the ossicles malleus, incus and stapes (M, I and S), and measured the tympanic membrane area, A1. The ossicular mass (in mg) is generally negatively allometric to skull mass (in g), the regression equation for the whole material (excluding true seals) being y = 1.373 x(0.513). However, for very small mammals the allometry approaches isometry. Within a group of large mammals no distinct allometry can be discerned. The true seals (Phocidae) are exceptional by having massive ossicles. The size relations within the middle ear are generally rather constant. However, the I/M relation is slightly positively allometric, y = 0.554 x(1.162). Two particularly isometric relations were found; the S/(M + I) relation for the ossicles characterized by the regression equation y = 0.054 x(0.993), and the relation between a two-dimensional measure of the ossicles and the tympanic membrane ares, (M + I)2/3 /A1. As in isometric ears the sound energy collected by the tympanic membrane is linearly related to its area, the latter isometry suggests that, regardless of animal size, a given ossicular cross-sectional area is exposed to a similar sound-induced stress. Possible morphological middle ear adaptations to particular acoustic environments are discussed. PMID:7559173

Nummela, S

1995-05-01

229

[Correction of prominent ears (author's transl)].  

PubMed

The the last 20 years plastic surgery was increasingly concerned with the correction of prominent ears. It is not possible to exactly define this anomaly, since it is not only subject to certain tangible criteria from a medical point of view, but also to the purely personal, esthetic perception of the patient. In the present publication an attempt is made to make a broad classification of those factors which together result in the impression of too prominent ears. There are basically 3 techniques for correcting this anomaly: 1. simple suture techniques, 2. simple section techniques, 3. combined techniques. The publication deals specifically with one operation-technique. It is basically a modification of the "Stenstroem-Anthelix-plastic;; procedure. This technique is indicated in the case of uncontoured, flatly prominent ears, whereby the correction is achieved by creating an anthelix bulge. An instrument which we developed as well as our dressing technique are described. Finally, the 123 operations which we carried out according to this technique between 1975 and 1979 are critically assessed. PMID:7007300

Staindl, O

1980-07-01

230

An investigation of ear necrosis in pigs  

PubMed Central

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

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

2013-01-01

231

Endoscopic assisted cochlear implants in ear malformations.  

PubMed

The aim of present study is to describe the use of the endoscopic assisted cochlear implant approach in cases with severely malformed temporal bones and with anomalous anatomy of the inner ear and tympanic cavity. Eight patients with malformed middle and inner ear and bilateral profound hearing loss were operated using an endoscopic assisted cochlear implant procedure at our tertiary university referral center between January and September 2013. Five patients received a cochlear implant using a suprameatal endoscopic assisted approach. A chart review of clinical data and videos from the operations was performed. All procedures were re-analyzed and codified. In all patients, discharge from hospital was on the third day post-surgery. No immediate or late postoperative complications were noted. The current mean follow-up is 6 months, with range between 4 and 12 months. This approach proved to be successful in cochlear implant placement. It guaranteed a very good control on the facial nerve, even in cases with difficult anatomical conditions, mainly thanks to the endoscopic procedure. It also permitted an appropriate anatomical orientation of the abnormal middle ear with a direct safe cochleostomy, when the round window position would have been difficult to treat using a traditional approach. PMID:25085636

Marchioni, Daniele; Soloperto, Davide; Guarnaccia, Maria C; Genovese, Elisabetta; Alicandri-Ciufelli, Matteo; Presutti, Livio

2014-08-01

232

Why Do Elephants Flap Their Ears?  

NASA Astrophysics Data System (ADS)

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.

Koffi, Moise; Jiji, Latif; Andreopoulos, Yiannis

2009-11-01

233

Middle-ear velocity transfer function, cochlear input immittance, and middle-ear efficiency in chinchilla  

PubMed Central

The transfer function HV between stapes velocity VS and sound pressure near the tympanic membrane PTM is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from HV measured in seven chinchilla ears and previously reported measurements of ME input admittance YTM and ME pressure gain GMEP [Ravicz and Rosowski, J. Acoust. Soc. Am. 132, 2437–2454 (2012); J. Acoust. Soc. Am. 133, 2208–2223 (2013)] in the same ears. The ME was open, and a pressure sensor was inserted into the cochlear vestibule for most measurements. The cochlear input admittance YC computed from HV and GMEP is controlled by a combination of mass and resistance and is consistent with a minimum-phase system up to 27?kHz. The real part Re{YC}, which relates cochlear sound power to inner-ear sound pressure, decreased gradually with frequency up to 25 kHz and more rapidly above that. MEE was about 0.5 between 0.1 and 8?kHz, higher than previous estimates in this species, and decreased sharply at higher frequencies. PMID:24116422

Ravicz, Michael E.; Rosowski, John J.

2013-01-01

234

Middle-ear velocity transfer function, cochlear input immittance, and middle-ear efficiency in chinchilla.  

PubMed

The transfer function H(V) between stapes velocity V(S) and sound pressure near the tympanic membrane P(TM) is a descriptor of sound transmission through the middle ear (ME). The ME power transmission efficiency (MEE), the ratio of sound power entering the cochlea to power entering the middle ear, was computed from H(V) measured in seven chinchilla ears and previously reported measurements of ME input admittance Y(TM) and ME pressure gain G(MEP) [Ravicz and Rosowski, J. Acoust. Soc. Am. 132, 2437-2454 (2012); J. Acoust. Soc. Am. 133, 2208-2223 (2013)] in the same ears. The ME was open, and a pressure sensor was inserted into the cochlear vestibule for most measurements. The cochlear input admittance Y(C) computed from H(V) and G(MEP) is controlled by a combination of mass and resistance and is consistent with a minimum-phase system up to 27 kHz. The real part Re{Y(C)}, which relates cochlear sound power to inner-ear sound pressure, decreased gradually with frequency up to 25 kHz and more rapidly above that. MEE was about 0.5 between 0.1 and 8 kHz, higher than previous estimates in this species, and decreased sharply at higher frequencies. PMID:24116422

Ravicz, Michael E; Rosowski, John J

2013-10-01

235

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

PubMed

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 ?-casein (CSN3). In addition, a chromosome-wide significant region affecting yield stress on BTA 11 was identified to be colocated with PAEP, coding for ?-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

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

2015-02-01

236

The role of polyphosphoinositides and their breakdown products in A23187-induced release of arachidonic acid from rabbit polymorphonuclear leucocytes.  

PubMed Central

Stimulation of rabbit polymorphonuclear leucocytes with A23187 causes phospholipase C mediated breakdown of polyphosphoinositides, as evidenced by accumulation of [3H]inositol-labelled inositol bisphosphate and inositol trisphosphate. At the same time the polyphosphoinositides and the products of their breakdown, diacylglycerol and phosphatidic acid, label rapidly with radioactive arachidonic acid. Enhancement of polyphosphoinositide labelling is not as great as enhancement of diacylglycerol or phosphatidic acid labelling, suggesting additional early activation of a second independent synthetic pathway to the last named lipids. Experiments using double (3H/14C) labelling, to distinguish pools with different rates of turnover, suggest the major pool of arachidonic acid used for synthesis of lipoxygenase metabolites turns over more slowly than arachidonic acid in diacylglycerol, but at about the same rate as arachidonic acid esterified in phosphatidylcholine or phosphatidylinositol. Further, when cells are prelabelled with [14C]arachidonic acid, then stimulated for 5 min, it is only from phosphatidylcholine, and to a lesser extent phosphatidylinositol, that radiolabel is lost. Release of arachidonic acid is probably via phospholipase A2, since it is blocked by the phospholipase A2 inhibitor manoalide. The absence of accumulated lysophosphatides can be explained by reacylation and, in the case of lysophosphatidylinositol, deacylation. The importance of phospholipase A2 in phosphatidylinositol breakdown contrasts with the major role of phospholipase C in polyphosphoinositide hydrolysis. Measurements of absolute free fatty acid levels, as well as studies showing a correlation between production of radiolabelled hydroxyeicosatetraenoic acids and release of radiolabel from the phospholipid pool, both suggest that hydrolysis of arachidonic acid esterified into phospholipids is the limiting factor regulating formation of lipoxygenase metabolites. By contrast with A23187, fMet-Leu-Phe (a widely used polymorphonuclear leucocyte activator) is a poor stimulant for arachidonic acid release unless a 'second signal' (e.g. cytochalasin B, or a product of A23187-stimulated cells) is also present. In the presence of cytochalasin B, fMet-Leu-Phe, like A23187, stimulates release of radiolabelled arachidonic acid principally from phosphatidylcholine. PMID:3026352

Meade, C J; Turner, G A; Bateman, P E

1986-01-01

237

[Materials for reconstruction of the middle ear].  

PubMed

To rehabilitate most cases of conductive hearing loss closure of ear drum perforations and rebuilding of the ossicular chain can be performed. Due to the great number of biocompatible bone substitute materials available it is occasionally difficult for the surgeon to choose the most favorable substitute. Autogenous structures (ossicles, cortical bone, cartilage) and allogenous tissues (ossicles, cortical bone, cartilage, dentin) are possible bone replacement materials. Xenogenic tissue is currently not used in middle ear surgery. Ionomer cement is a hybrid material for replacement of bone but does not fit direct classification of the various classes of alloplastic materials in current use: that is, metals (gold, steel wire, platinum, titanium), plastics (polyethylene, polytetrafluorethylene) and ceramics (ceramic oxide, carbon, calcium-phosphate ceramic, vitreous ceramic). For restoration of the sound conductive apparatus preference is given to autogenous ossicles because cortical bone is resorbed and cartilage weakens over time. Most surgeons do not use allogenous tissue, because of the possible transmission of such infectious disease as immunodeficiency syndrome or Creutzfeldt-Jakob disease. Only dentin deserves special attention as a possible bone substitute in the middle ear because its form can be preserved during sterilization. Based on the observations available to date, it becomes apparent that titanium implants hold greater promise than gold. Form-stable synthetic materials are not generally recommended due to foreign body reactions which have been confirmed by many investigators. Ceramic materials (e.g. ceramic oxide, carbon, calcium-phosphate ceramic, glass ceramic) are well tolerated in the middle ear and have also proved to be useful over time. Hybrid bone substitute ionomer cement is easily workable and well integrated, showing a good functional outcome. For many years good results in otosclerosis surgery have been achieved with a prosthesis made of platinum-wire and Teflon. Short-term follow-up periods hold great promise with pistons made of gold. Autogenous ossicles, ionomer cement and recently titanium protheses--as far as usable--are employed by the author for reconstructing the middle ear. For the time being platinum-Teflon prostheses and gold are used in otosclerosis surgery. PMID:10197273

Geyer, G

1999-02-01

238

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

PubMed

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

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

2014-11-01

239

Sham control methods used in ear-acupuncture/ear-acupressure randomized controlled trials: a systematic review.  

PubMed

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

Zhang, Claire Shuiqing; Yang, Angela Weihong; Zhang, Anthony Lin; May, Brian H; Xue, Charlie Changli

2014-03-01

240

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

PubMed Central

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

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

2014-01-01

241

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

NASA Astrophysics Data System (ADS)

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.

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

2003-06-01

242

Manual therapy and ear pain: a report of four cases  

PubMed Central

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

Murphy, Donald R.; Gay, Charles W.

2011-01-01

243

Review of congenital inner ear abnormalities on CT temporal bone  

PubMed Central

The aetiology of profound hearing loss in children is complex and multifactorial. Congenital inner ear abnormality is a major cause of hearing loss in children. CT temporal bone imaging is the modality of choice in the investigation of hearing loss. Recognising the congenital abnormalities of the inner ear guides the clinician's management of the condition. This pictorial essay illustrates the congenital abnormalities of the inner ear on high resolution CT temporal bone images and correlation with developmental arrest during embryology. PMID:21849370

Yiin, R S Z; Tang, P H; Tan, T Y

2011-01-01

244

Abnormal metabolism of arachidonic acid in chronic inflammatory bowel disease: enhanced release of leucotriene B4 from activated neutrophils.  

PubMed Central

The metabolism of endogenous arachidonic acid P(AA) was investigated in activated neutrophils from 20 patients with Crohn's disease, 20 with ulcerative colitis, and 25 healthy volunteers. 1-14C-P(AA) was incorporated into intracellular pools of phospholipids prior to activation of the cells with ionophore A23187 and analyses of released arachidonic acid metabolites by thin layer chromatography. Total release of radioactivity expressing the release of arachidonic acid and its metabolites, was equal in the experimental and control groups, which suggests a normal substrate availability. In contrast, there was a marked increase in the relative release of leucotriene B4 (LTB4) and its omega-oxidation products, 20-hydroxy-LTB4 (20-OH-LTB4) and 20-carboxy-LTB4 (20-COOH-LTB4), with LTB4 values exceeding the reference interval in seven of 20 patients with Crohn's disease, median 8.7%, and in six of 20 patients with ulcerative colitis, median 7.7%, as compared with a median of 5.3% in healthy volunteers. Furthermore, a decreased release of unmetabolised arachidonic acid, correlating inversely with the release of LTB4 in all experimental and control groups, and normal values for the production of other metabolites of arachidonic acid--for example, 5-hydroxyeicosatetraenoic acid (5-HETE) and 12-hydroxyheptadecatrienoic acid (HHT), point to an enzymatic abnormality such as increased activity of leucotriene B synthetase. An increased capacity for release of LTB4, the major pro-inflammatory metabolite of arachidonic acid lipoxygenation by polymorphonuclear leucocytes, may contribute to perpetuation of the inflammation and to tissue destruction in chronic inflammatory bowel disease. Our findings agree with previous reports of an increased release of LTB4 by the colonic mucosa in this condition. PMID:3030903

Nielsen, O H; Ahnfelt-Rønne, I; Elmgreen, J

1987-01-01

245

Protective Effect of Comaruman, a Pectin of Cinquefoil Comarum palustre L., on Acetic Acid-Induced Colitis in Mice  

Microsoft Academic Search

The efficacy of comaruman CP, a pectin of marsh cinquefoil Comarum palustre L., was investigated using a model of acetic acid-induced colitis in mice. Mice were administered comaruman CP orally 2 days prior to rectal injection of 5% acetic acid and examined for colonic damage 24 hr later. Colonic inflammation was characterized by macroscopical injury, higher levels of myeloperoxidase activity, enhanced

Sergey V. Popov; Raisa G. Ovodova; Pavel A. Markov; Ida R. Nikitina; Yury S. Ovodov

2006-01-01

246

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...

247

A case report of meningioma extending to the middle ear  

PubMed Central

Extracranial meningioma with extension into a middle ear is very uncommon. A 74-year-old female was admitted to our hospital with right ear bleeding when removing earwax. In this case, magnetic resonance imaging, computed tomography, her past history and operative findings would consider as infiltrative growth from the right sphenoid ridge meningioma to the right middle ear via the right petrous pyramid and bilateral optic nerve. She underwent only partial extirpation with decompression for optic nerve, rather than total extirpation including middle ear and temporal bone, due to wide invasion of the middle cranial fossa and caversinus sinus. PMID:24765466

Kusunoki, Takeshi; Ikeda, Katsuhisa; Miyashita, Mie

2012-01-01

248

Otosclerosis associated with type B-1 inner ear malformation  

PubMed Central

Summary Malformations of bony inner ear are rare anomalies occurring in approximately 20% of patients with congenital sensorineural hearing loss. Conductive hearing loss is usually associated with abnormalities of the external and middle ear. Recent reports of patients with lateral semicircular canal malformations indicate inner ear malformations to be associated with sensorineural or conductive hearing loss. Differential diagnosis of conductive hearing loss should include otosclerosis, isolated ossicular deformities, inner ear anomalies or a combination of these. In this report, a case is described with right vestibule-lateral semicircular canal dysplasia presenting at our centre with bilateral otosclerosis. PMID:20948592

De Stefano, A; Dispenza, F; Aggarwal, N; Russo, A

2010-01-01

249

EARS, MARS combined radio observations - 2014  

NASA Astrophysics Data System (ADS)

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.

Tomezzoli, Giancarlo

2014-02-01

250

Empirical Evaluation of Advanced Ear Biometrics Ping Yan Kevin W. Bowyer  

E-print Network

Empirical Evaluation of Advanced Ear Biometrics Ping Yan Kevin W. Bowyer Department of Computer experimental inves- tigation of ear biometrics to date. Approaches consid- ered include a PCA ("eigen-ear the robustness and variability of ear biometrics, ear symmetry is also in- vestigated. In our experiments around

Bowyer, Kevin W.

251

Ear emergence in perennial ryegrass as affected by differences in light and temperature before ear initiation  

Microsoft Academic Search

The effects of differences in daylength and temperature, before ear initiation, on subsequent emergence in perennial ryegrass selections were studied in the glasshouse. When no artificial light or heat was used, prolific and uniform emergence was observed. Of seven other combinations compared, uniform but much earlier emergence was obtained from only that treatment where the natural sequence of events, cold

S. O. Fejer

1960-01-01

252

Maximum Real-Ear Gain of in-the-Ear Hearing Aids.  

ERIC Educational Resources Information Center

Three hearing aid manufacturers provided custom full-shell in-the-ear hearing aids designed for maximum acoustic gain for each of three hearing-impaired adults. Full-on coupler gain curves were similar across all nine hearing aids, with individual differences producing substantial variance in insertion gain across hearing aids. (Author/DB)

Erickson, Faye N.; Van Tasell, Dianne J.

1991-01-01

253

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

SciTech Connect

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.

Greco, N.J.

1985-01-01

254

Arachidonic acid metabolism and pathophysiologic aspects of subarachnoid hemorrhage in rats.  

PubMed

We studied the ex vivo production of prostaglandin D2, prostaglandin E2, 6-ketoprostaglandin F1 alpha, and leukotriene C4 in the brain tissue of rats subjected to experimental subarachnoid hemorrhage. The ex vivo method allows the study of arachidonic acid metabolites released from brain slices at different times after subarachnoid hemorrhage induction and reflects the residual capacity for arachidonic acid metabolism after the pathologic event. The rats were sacrificed 30 minutes, 1 and 6 hours, and 2 days after subarachnoid hemorrhage was induced by the injection of 0.30 ml autologous arterial blood into the cisterna magna. Concentration of prostaglandin D2 and 6-ketoprostaglandin F1 alpha was increased significantly relative to control 2 days after induction. The concentration of prostaglandin E2 was increased significantly 6 hours after induction, while ex vivo production of leukotriene C4 was increased significantly at 1 and 6 hours and 2 days. The correlation between these results and the occurrence of vasospasm after subarachnoid hemorrhage is discussed. The results obtained from the ex vivo incubation of brain tissue slices after experimental subarachnoid hemorrhage suggest that after the hemorrhage there is a significant modification of brain eicosanoid metabolism, which could be of great importance in interpreting the pathogenesis of subarachnoid hemorrhage-related neuronal impairment. PMID:2106176

Gaetani, P; Marzatico, F; Rodriguez y Baena, R; Pacchiarini, L; Viganò, T; Grignani, G; Crivellari, M T; Benzi, G

1990-02-01

255

Altered arachidonic acid cascade enzymes in postmortem brain from bipolar disorder patients.  

PubMed

Mood stabilizers that are approved for treating bipolar disorder (BD), when given chronically to rats, decrease expression of markers of the brain arachidonic metabolic cascade, and reduce excitotoxicity and neuroinflammation-induced upregulation of these markers. These observations, plus evidence for neuroinflammation and excitotoxicity in BD, suggest that arachidonic acid (AA) cascade markers are upregulated in the BD brain. To test this hypothesis, these markers were measured in postmortem frontal cortex from 10 BD patients and 10 age-matched controls. Mean protein and mRNA levels of AA-selective cytosolic phospholipase A(2) (cPLA(2)) IVA, secretory sPLA(2) IIA, cyclooxygenase (COX)-2 and membrane prostaglandin E synthase (mPGES) were significantly elevated in the BD cortex. Levels of COX-1 and cytosolic PGES (cPGES) were significantly reduced relative to controls, whereas Ca(2+)-independent iPLA(2)VIA, 5-, 12-, and 15-lipoxygenase, thromboxane synthase and cytochrome p450 epoxygenase protein and mRNA levels were not significantly different. These results confirm that the brain AA cascade is disturbed in BD, and that certain enzymes associated with AA release from membrane phospholipid and with its downstream metabolism are upregulated. As mood stabilizers downregulate many of these brain enzymes in animal models, their clinical efficacy may depend on suppressing a pathologically upregulated cascade in BD. An upregulated cascade should be considered as a target for drug development and for neuroimaging in BD. PMID:20038946

Kim, H-W; Rapoport, S I; Rao, J S

2011-04-01

256

Increase in class 2 aldehyde dehydrogenase expression by arachidonic acid in rat hepatoma cells.  

PubMed Central

Aldehyde dehydrogenase (ALDH) is a family of several isoenzymes important in cell defence against both exogenous and endogenous aldehydes. Compared with normal hepatocytes, in rat hepatoma cells the following changes in the expression of ALDH occur: cytosolic class 3 ALDH expression appears and mitochondrial class 2 ALDH decreases. In parallel with these changes, a decrease in the polyunsaturated fatty acid content in membrane phospholipids occurs. In the present study we demonstrated that restoring the levels of arachidonic acid in 7777 and JM2 rat hepatoma cell lines to those seen in hepatocytes decreases hepatoma cell growth, and increases class 2 ALDH activity. This latter effect appears to be due to an increased gene transcription of class 2 ALDH. To account for this increase, we examined whether peroxisome-proliferator-activated receptors (PPARs) or lipid peroxidation were involved. We demonstrated a stimulation of PPAR expression, which is different in the two hepatoma cell lines: in the 7777 cell line, there was an increase in PPAR alpha expression, whereas PPAR gamma expression increased in JM2 cells. We also found increased lipid peroxidation, but this increase became evident at a later stage when class 2 ALDH expression had already increased. In conclusion, arachidonic acid added to the culture medium of hepatoma cell lines is able to partially restore the normal phenotype of class 2 ALDH, in addition to a decrease in cell growth. PMID:11463352

Canuto, R A; Ferro, M; Salvo, R A; Bassi, A M; Trombetta, A; Maggiora, M; Martinasso, G; Lindahl, R; Muzio, G

2001-01-01

257

Physiological inhibitory effect of ocs in arachidonic acid-rich Parietochloris incisa (trebouxiophyceae, chlorophyta)  

NASA Astrophysics Data System (ADS)

Parietochloris incisa is an arachidonic acid-rich snow green alga. The main physiological profiles, such as ash free dry weight (AFDW), chlorophyll, carotenoid, protein and total fatty acids (TFA), in this alga exposed to old culture supernatant (OCS) at the decline phase or its crude ethyl acetate extracts (CEAE) were investigated by using tubular photobioreactors of different diameters. Results showed that both OCS and CEAE had strong inhibitory effect on the above physiological parameters. The longer the culture was exposed to OCS and the more CEAE were added into the algal culture, the more the above physiological properties were inhibited. Arachidonic acid (AA), the dominant component of fatty acids in this alga, was also seriously inhibited with respect to total TFA, AFDW of cell mass, or culture volume, due to a probable reduction of enzymes activities catalyzing chain elongation from C18; 1?9 to AA. These results incontestably evidenced that some CEAE dissolving substances existing in OCS. like auto-inhibitors, inhibited P. incisa growth through feedback. Hence, any efficient removal of auto-inhibitors from algal culture to decrease their bioactivity could be good for maximal production of desired products like AA.

Liu, Jian-Guo; Zhang, Cheng-Wu; Cohen, Zvi; Richmond, Amos

2002-09-01

258

Some secondary plant metabolites in Desmodium adscendens and their effects on arachidonic acid metabolism.  

PubMed

The effects of three chemically different groups of compounds, (triterpenoid saponins, beta-phenylethylamines and tetrahydroisoquinolines), known to be present in Desmodium adscendens, on plasma membrane ion channel, cytochrome P450 NADPH-dependent oxygenation of arachidonic acid, and production of prostaglandins by the cyclooxygenase enzyme system, are described. The very high-conductance calcium-activated potassium ion channel, which is responsible for the maintenance of tone in smooth muscles, was activated by the saponins. The cytochrome P450 NADPH-dependent monooxygenase reaction, which produces epoxy- and hydroxylated eicosanoids from arachidonic acid metabolism, was inhibited by an analogue of the tetrahydroisoquinoline present in the plant. This analogue also acted as a reductant in the prostaglandin synthesizing system using microsomes from ram seminal vesicles. The same system was activated by the beta-phenylethylamines found in the plant material, with the formation of more prostaglandins, the type being dependent on the amount of cyclooxygenase enzyme used and the presence or absence of coenzyme. PMID:1438471

Addy, M E

1992-09-01

259

Inhibitory effects of plant-derived flavonoids and phenolic acids on malonaldehyde formation from ethyl arachidonate.  

PubMed

The antioxidant activities of naturally occurring plant compounds were measured in a lipid peroxidation system consisting of ethyl arachidonate and Fenton's reagent. Inhibitory effects of 24 plant-derived flavonoids and 5 phenolic acids on malonaldehyde (MA) formation from ethyl arachidonate were examined using gas chromatography (GC) with a nitrogen-phosphorus detector (NPD). Luteolin, which showed the strongest antioxidant activity, inhibited MA formation by 94% and 97% at the levels of 0.5 and 1.0 mM, respectively. The antioxidant activities of the flavones and flavonols decreased in the following order: luteolin > rhamnetin > fisetin > kaempferol > morin > quercetin. Among the flavanones tested, hesperitin, taxifolin, and naringenin exhibited appreciable antioxidant activities (61-84%) at the 1.0 mM level. The inhibitory effect of epigallocatechin gallate (82.5% at the 1.0 mM level) was the strongest among the flavan-3-ols tested. Ferulic acid had the most potent antioxidant activity (74.6% at the 1.0 mM level) of the phenolic acids tested. PMID:14611194

Lee, Kwang-Geun; Shibamoto, Takayuki; Takeoka, Gary R; Lee, Sung-Eun; Kim, Jeong-Han; Park, Byeoung-Soo

2003-11-19

260

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

SciTech Connect

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.

Catella, F.; Lawson, J.A.; Fitzgerald, D.J.; FitzGerald, G.A. (Vanderbilt Univ., Nashville, TN (USA))

1990-08-01

261

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

PubMed Central

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.

Aslan, Mutay; Özcan, Filiz; Tuzcu, Hazal; K?raç, Ebru; Elpek, Gulsum O

2014-01-01

262

Carnosic Acid Induces Apoptosis Through Reactive Oxygen Species-mediated Endoplasmic Reticulum Stress Induction in Human Renal Carcinoma Caki Cells  

PubMed Central

Background: Carnosic acid, which is one of extract components of rosemary, has anti-inflammatory, anti-oxidant, and anti-cancer effects. However, the anti-cancer effect of carnosic acid in human renal carcinoma cells is unknown. Methods: Flow cytometry analysis was used to examine the effects of carnosic acid on apoptosis, and Asp-Glu-Val-Asp-ase activity assay kit was used to investigate the involvement of caspase activation. To determine protein expression of apoptotic and endoplasmic reticulum (ER) stress-related proteins, we used Western blotting. Intracellular accumulation of reactive oxygen species (ROS) was determined using the fluorescent probes 2’, 7’-dichlorodihydrofluorescein diacetate (H2DCFDA). Results: Carnosic acid induced sub-diploid DNA content, sub-G1, population and poly (ADP-ribose) polymerase (PARP) cleavage and activated caspase-3. A pan-caspase inhibitor, a benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone, markedly reduced apoptosis in carnosic acid-treated cells. Carnosic acid promoted intracellular ROS production, and pretreatment with the ROS scavengers (N-acetyl-L-cysteine and glutathione ethyl ester) inhibited carnosic acid-induced apoptosis. Furthermore, carnosic acid also induced expression of ER stress marker proteins, including activating transcription factor 4 (ATF4) and CCAAT/enhancer-binding protein-homologous protein (CHOP), in a dose- and time-dependent manner. Down-regulation of ATF4 and CHOP by small interfering RNA (siRNA) markedly reduced carnosic acid-induced sub-G1 population and PARP cleavage. In addition, carnosic acid induced apoptosis in human breast carcinoma MDA-MB-361 and human hepatocellular carcinoma SK-HEP1 cells, but not in normal human skin fibroblast cells and normal mouse kidney epithelial TMCK-1 cells. Conclusion: Carnosic acid induced apoptosis through production of ROS and induction of ER stress in human renal carcinoma Caki cells. PMID:25337586

Min, Kyoung-jin; Jung, Kyong-Jin; Kwon, Taeg Kyu

2014-01-01

263

Vibrations in the human middle ear  

PubMed Central

Summary Background Middle ear surgery techniques can improve hearing destroyed by disease, but results of treatment are difficult to predict. Therefore, researchers use a Laser Doppler Vibrometer to measure vibrations of human middle ear ossicles. Material/Methods Measurements of ossicular chain vibrations are performed on fresh human temporal bone specimens using Laser Doppler Vibrometer. Vibrations of stapes are recorded in 3 cases: 1) for intact ossicular chain, 2) when incus long process is removed, and 3) after long process reconstruction with bone cement. A typical analysis of transfer function is completed by other methods applied in dynamics. Results Measurements and analysis of stapes vibrations in case of intact and damaged ossicular chain show regular and irregular behavior which can be recognize with the help of phase portraits, recurrence plots, correlation dimension, and Hurst and Lyapunov exponents. The long process reconstruction with bone cement gives good results in improving hearing. Conclusions Recurrence plots, and Lyapunov and Hurst exponents used in the study complete information obtained from transfer function and can be employed to enrich the classical approach to ossicular chain vibrations. PMID:22129895

Rusinek, Rafa?; Szyma?ski, Marcin; Warmi?ski, Jerzy; Zadrozniak, Marek; Morshed, Kamal

2011-01-01

264

Sp8 regulates inner ear development  

PubMed Central

A forward genetic screen of N-ethyl-N-nitrosourea mutagenized Xenopus tropicalis has identified an inner ear mutant named eclipse (ecl). Mutants developed enlarged otic vesicles and various defects of otoconia development; they also showed abnormal circular and inverted swimming patterns. Positional cloning identified specificity protein 8 (sp8), which was previously found to regulate limb and brain development. Two different loss-of-function approaches using transcription activator-like effector nucleases and morpholino oligonucleotides confirmed that the ecl mutant phenotype is caused by down-regulation of sp8. Depletion of sp8 resulted in otic dysmorphogenesis, such as uncompartmentalized and enlarged otic vesicles, epithelial dilation with abnormal sensory end organs. When overexpressed, sp8 was sufficient to induce ectopic otic vesicles possessing sensory hair cells, neurofilament innervation in a thickened sensory epithelium, and otoconia, all of which are found in the endogenous otic vesicle. We propose that sp8 is an important factor for initiation and elaboration of inner ear development. PMID:24722637

Chung, Hyeyoung A.; Medina-Ruiz, Sofia; Harland, Richard M.

2014-01-01

265

Enhanced visualization of inner ear structures  

NASA Astrophysics Data System (ADS)

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.

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

2004-07-01

266

Evaluation of fungal flora in normal and diseased canine ears.  

PubMed

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

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

2010-12-01

267

496. Phys. Lett A., (2006) A.G.Ramm, The shape of the ear canal The shape of the ear canal #+  

E-print Network

496. Phys. Lett A., (2006) A.G.Ramm, The shape of the ear canal 1 #12; The shape of the ear canal@math.ksu.edu Abstract It is proved that the measurement of the acoustic pressure on the ear membrane allows one to determine the shape of the ear canal uniquely. 1 Introduction Consider a bounded domain D # R n , n = 3

268

Within-ear and across-ear interference in a cocktail-party listening task Douglas S. Brungart1 and Brian D. Simpson2  

E-print Network

Within-ear and across-ear interference in a cocktail-party listening task Douglas S. Brungart1 talker is present in the same ear as the target speech or when a masking talker is present in a different ear than the target speech, little is known about selective auditory attention in tasks with a target

Allen, Jont

269

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

PubMed

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

Röhm, E; Adam, E

1986-01-01

270

Can you hear me now? Understanding vertebrate middle ear development.  

PubMed

The middle ear is a composite organ formed from all three germ layers and the neural crest. It provides the link between the outside world and the inner ear, where sound is transduced and routed to the brain for processing. Extensive classical and modern studies have described the complex morphology and origin of the middle ear. Non-mammalian vertebrates have a single ossicle, the columella. Mammals have three functionally equivalent ossicles, designated the malleus, incus and stapes. In this review, I focus on the role of genes known to function in the middle ear. Genetic studies are beginning to unravel the induction and patterning of the multiple middle ear elements including the tympanum, skeletal elements, the air-filled cavity, and the insertion point into the inner ear oval window. Future studies that elucidate the integrated spatio-temporal signaling mechanisms required to pattern the middle ear organ system are needed. The longer-term translational benefits of understanding normal and abnormal ear development will have a direct impact on human health outcomes. PMID:21196256

Chapman, Susan Caroline

2011-01-01

271

Can you hear me now? Understanding vertebrate middle ear development  

PubMed Central

The middle ear is a composite organ formed from all three germ layers and the neural crest. It provides the link between the outside world and the inner ear, where sound is transduced and routed to the brain for processing. Extensive classical and modern studies have described the complex morphology and origin of the middle ear. Non-mammalian vertebrates have a single ossicle, the columella. Mammals have three functionally equivalent ossicles, designated the malleus, incus and stapes. In this review, I focus on the role of genes known to function in the middle ear. Genetic studies are beginning to unravel the induction and patterning of the multiple middle ear elements including the tympanum, skeletal elements, the air-filled cavity, and the insertion point into the inner ear oval window. Future studies that elucidate the integrated spatio-temporal signaling mechanisms required to pattern the middle ear organ system are needed. The longer-term translational benefits of understanding normal and abnormal ear development will have a direct impact on human health outcomes. PMID:21196256

Chapman, Susan Caroline

2010-01-01

272

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...

273

Within-consonant perceptual differences in the hearing impaired ear  

E-print Network

) The consonant recognition of 17 ears with sensorineural hearing loss is evaluated for 14 consonants /p, t, k, f and Delhorne (1987). Overall, the effects of hearing impaWithin-consonant perceptual differences in the hearing impaired ear Andrea Trevinoa) and Jont B

Allen, Jont

274

2 Cases of Intracranial Meningioma Extending into the Middle Ear  

Microsoft Academic Search

The meningiomas are slowly growing tumors arising from meningoepithelial cells and they generally occur throughout the cra- niospinal axis. Meningiomas extending to the middle ear cavity are uncommom and these patients complain of otologic symptoms such as hearing loss, ear fullness, or otorrhea. Clinical findings frequently suggest otitis media resistant to conventional treatments, thereby facilitating misdiagnosis. CT and MRI of

Ki-Hong Chang; Jae-Hyun Seo; Dong Chang Lee; Myung Han Lee

2009-01-01

275

[Inverted caloric nystagmus of perforated ears upon air caloric stimulation].  

PubMed

It is well known that inverted caloric nystagmus is seen during air caloric testing in cases of chronic otitis media. The mechanism of inversion and its clinical significance are discussed here. Temperature changes in the tympanic cavity and external ear canal were measured with a microthermister and a digital tester in seventeen ears with tympanic membrane perforation, during bithermal air caloric testing. The tympanic cavity mucosa was cooled by hot stimulation because of the evaporation of heat. When the perforation was closed or humidified air was used, the tympanic cavity mucosa was not cooled by hot stimulation and the inverted caloric nystagmus changed to a normal response. Inverted caloric nystagmus occurred in 30.4% of 335 ears affected by chronic otitis media with perforation. Inverted caloric nystagmus occurred in 90 ears with hot stimulation and in 12 ears with cold stimulation. Inverted caloric nystagmus turned to normal response after myringoplasty in all of 10 ears. The cooling effect caused by evaporation of water from the moist middle ear mucosa during dry air blowing and direct thermal conduction to the vestibulum through a perforation of the ear drum and inversion of the endolymphatic convection seemed to cause the inversion. PMID:2040915

Koide, C

1991-03-01

276

Rhabdomyosarcoma in middle ear of an adult: a rare presentation  

PubMed Central

Rhabdomyosarcoma of the middle ear is a rare tumor, even rarer in adults and has a very poor prognosis. We report here an unusual case of rhabdomyosarcoma in middle ear of an adult, mimicking chronic suppurative otitis media and facial nerve palsy. PMID:24960749

Bhargava, S; Grover, M; Mehta, J; Maheshwari, V

2012-01-01

277

Preventing Cauliflower Ear with a Modified Tie-Through Technique.  

ERIC Educational Resources Information Center

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)

Dimeff, Robert J.; Hough, David O.

1989-01-01

278

The influence of long chain polyunsaturate supplementation on docosahexaenoic acid and arachidonic acid in baboon neonate central nervous system  

Microsoft Academic Search

BACKGROUND: Docosahexaenoic acid (DHA) and arachidonic acid (ARA) are major components of the cerebral cortex and visual system, where they play a critical role in neural development. We quantitatively mapped fatty acids in 26 regions of the four-week-old breastfed baboon CNS, and studied the influence of dietary DHA and ARA supplementation and prematurity on CNS DHA and ARA concentrations. METHODS:

Guan-Yeu Diau; Andrea T Hsieh; Eszter A Sarkadi-Nagy; Vasuki Wijendran; Peter W Nathanielsz; J Thomas Brenna

2005-01-01

279

Effect of dietary arachidonic acid levels on growth and survival of gilthead sea bream ( Sparus aurata L.) larvae  

Microsoft Academic Search

In order to determine the effect of different levels of arachidonic acid (AA) in microdiets on growth and survival of gilthead seabream larvae, two experiments were carried out. In the first experiment, 17-day old larvae were fed microdiets for 14 days. In this trial, we tested four diets with a similar docosahexaenoic acid (DHA)\\/eicosapentaenoic acid (EPA) ratio and AA in

M Bessonart; M. S Izquierdo; M Salhi; C. M Hernández-Cruz; M. M González; H Fernández-Palacios

1999-01-01

280

Synthesis and applications of stereospecifically (3)H-labeled arachidonic acids as mechanistic probes for lipoxygenase and cyclooxygenase catalysis.  

PubMed

Stereospecifically (3)H-labeled substrates are useful tools in studying the mechanism of hydrogen abstractions involved in the oxygenation of polyunsaturated fatty acids. Here, we describe modified methods for the synthesis of arachidonic acids labeled with a single chiral tritium on the methylene groups at carbons 10 or 13. The appropriate starting material is a ketooctadecanoic acid which is prepared from an unsaturated C18 fatty acid precursor or by total synthesis. The (3)H label is introduced by NaB(3)H(4) reduction and the resulting tritiated hydroxy fatty acid then is tosylated, separated into the enantiomers by chiral phase HPLC, and subsequently transformed into stearic acids. A variety of stereospecifically labeled unsaturated fatty acids are obtained using literature methods of microbial transformation with the fungus Saprolegnia parasitica. Two applications are described: (i) In incubations of [10S-(3)H]- and [10R-(3)H]arachidonic acids in human psoriatic scales we show that a 12R-lipoxygenase accounts not only for synthesis of the major product 12R-HETE, but it contributes also, through subsequent isomerization, to the minor amounts of 12S-HETE. (ii) The [10R-(3)H]- and [10S-(3)H]arachidonic acids were also used to demonstrate that prostaglandin ring formation by cyclooxygenases does not involve carbocation formation at C-10 of arachidonic acid as was hypothesized recently. PMID:10933865

Schneider, C; Boeglin, W E; Lai, S; Cha, J K; Brash, A R

2000-08-15

281

Arachidonic acid (AA) is thought to serve as an intercellular messenger in many parts of the nervous system (Attwell et  

E-print Network

Arachidonic acid (AA) is thought to serve as an intercellular messenger in many parts of the nervous system (Attwell et al. 1993). The release of AA from membrane phospholipids can be stimulated. In the case of glutamate, release of AA is evoked by activation of NMDA receptors (Dumuis et al. 1988

Huettner, James E.

282

Arachidonic acid- and docosahexaenoic acid-enriched formulas modulate antigen-specific T cell responses to influenza virus in  

Microsoft Academic Search

Background: Whereas the immunomodulatory effects of feeding either arachidonic acid (AA) or docosahexaenoic acid (DHA) sep- arately have been previously investigated, little is known about the immunomodulatory efficacy of AA or DHA when they are fed in combination as infant formula ingredients. Objective: The objective of this study was to investigate the ability of AA- and DHA(AA\\/DHA)-enriched infant formula to

Josep Bassaganya-Riera; Amir J Guri; Alexis M Noble; Kathryn A Reynolds; Jennifer King; Cynthia M Wood; Michael Ashby; Deshanie Rai; Raquel Hontecillas

283

Adenovirus E3-6.7K Maintains Calcium Homeostasis and Prevents Apoptosis and Arachidonic Acid Release  

E-print Network

to maintain endoplasmic reticulum-Ca2+ homeostasis and inhibit the induction of apoptosis by thapsigargin. The presence of E3-6.7K also lead to a reduction in the TNF-induced release of arachidonic acid from transfected U937 human histiocytic lymphoma cells...

Moise, Alexander R.; Grant, Jason R.; Vitalis, Timothy Z.; Jefferies, Wilfred A.

2002-02-01

284

Many of the enzymes, receptors and eicosanoid metabo-lites of the arachidonate cascade (FIG. 1) are key thera-  

E-print Network

Many of the enzymes, receptors and eicosanoid metabo- lites of the arachidonate cascade (FIG. 1 of cardiovascular diseases such as hypertension and stroke13­16 . The epoxygenase CYP enzymes generate diminishing their beneficial cardiovascular properties20,21 . Inhibition of this enzyme is therefore

Hammock, Bruce D.

285

CO-EXPOSURE OF HUMAN AIRWAY EPITHELIAL CELLS TO OZONE AND PARTICULATE MATTER: EFFECTS ON ARACHIDONIC ACID METABOLISM  

EPA Science Inventory

Co-exposure of human airway epithelial cells to ozone and particulate matter: effects on arachidonic acid metabolism. D. Stamm1, L. Dailey2, M.C. Madden2 1 University of North Carolina-Chapel Hill, School of Medicine 2 U.S. EPA, ORD, NHEERL, HSD, Chapel Hill, NC, USA...

286

Catalase Overexpression Reduces Lactic Acid-Induced Oxidative Stress in Saccharomyces cerevisiae?  

PubMed Central

Industrial production of lactic acid with the current pyruvate decarboxylase-negative Saccharomyces cerevisiae strains requires aeration to allow for respiratory generation of ATP to facilitate growth and, even under nongrowing conditions, cellular maintenance. In the current study, we observed an inhibition of aerobic growth in the presence of lactic acid. Unexpectedly, the cyb2? reference strain, used to avoid aerobic consumption of lactic acid, had a specific growth rate of 0.25 h?1 in anaerobic batch cultures containing lactic acid but only 0.16 h?1 in identical aerobic cultures. Measurements of aerobic cultures of S. cerevisiae showed that the addition of lactic acid to the growth medium resulted in elevated levels of reactive oxygen species (ROS). To reduce the accumulation of lactic acid-induced ROS, cytosolic catalase (CTT1) was overexpressed by replacing the native promoter with the strong constitutive TPI1 promoter. Increased activity of catalase was confirmed and later correlated with decreased levels of ROS and increased specific growth rates in the presence of high lactic acid concentrations. The increased fitness of this genetically modified strain demonstrates the successful attenuation of additional stress that is derived from aerobic metabolism and may provide the basis for enhanced (micro)aerobic production of organic acids in S. cerevisiae. PMID:19251894

Abbott, Derek A.; Suir, Erwin; Duong, Giang-Huong; de Hulster, Erik; Pronk, Jack T.; van Maris, Antonius J. A.

2009-01-01

287

Acid-induced gelation behavior of casein/whey protein solutions assessed by oscillatory rheology.  

PubMed

Gelation process of acid-induced casein gels was studied using response surface method (RSM). Ratio of casein to whey proteins, incubation and heating temperatures were independent variables. Final storage modulus (G') measured 200 min after the addition of glucono-?-lactone and the gelation time i.e. the time at which G' of gels became greater than 1 Pa were the parameters studied. Incubation temperature strongly affected both parameters. The higher the incubation temperature, the lower was the G' and the shorter the gelation time. Increased heating temperature however, increased the G' but again shortened the gelation time. Increase in G' was attributed to the formation of disulphide cross-linkages between denatured whey proteins and casein chains; whilst the latter was legitimized by considering the higher isoelectric pH of whey proteins. Maximum response (G'?=?268.93 Pa) was obtained at 2.7 % w/w, 25 °C and 90 °C for casein content, incubation and heating temperatures, respectively. PMID:25190871

Sadeghi, Mahboubeh; Madadlou, Ashkan; Khosrowshahi, Asghar; Mohammadifar, Mohammadamin

2014-09-01

288

Effects of ionizing radiation on retinoic acid-inducible gene-I-like receptors.  

PubMed

Retinoic acid-inducible gene-I (RIG-I)-like receptors [RLRs; RIG-I and melanoma differentiation-associated gene 5 (MDA5)] sense virus-derived RNA or a synthetic analog of double-stranded RNA polyinosinic-polycytidylic acid [poly(I:C)] and are responsible for host defense against viruses. However, it remains unclear whether radiation affects RLRs. Therefore, the present study investigated the effects of ionizing radiation on RIG-I and MDA5 expression and the response to poly(I:C) using THP1 (human monocytic cell line)-derived macrophages. Non- and X-irradiated (1-10 Gy) macrophages expressed RIG-I and MDA5 at mRNA and protein levels and there was no significant difference in the expression levels. Non- and X-irradiated macrophages expressed antiviral cytokine interferon (IFN)-? mRNA following poly(I:C)-low molecular weight/LyoVec™ and poly(I:C)-high molecular weight/LyoVec™ stimulation, the agonist of RIG-I and MDA5, respectively. In line with the results of the expression of RIG-I and MDA5, no significant difference in the expression of IFN-? mRNA was observed between non- and X-irradiation. These results indicate that ionizing radiation hardly affects RLR expression and the response to their agonist poly(I:C) in THP1-derived macrophages. PMID:25469248

Yoshino, Hironori; Saitoh, Takahiro; Kozakai, Masataka; Kashiwakura, Ikuo

2015-01-01

289

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

PubMed

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

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

2014-09-01

290

Protocatechuic acid induces angiogenesis through PI3K-Akt-eNOS-VEGF signalling pathway.  

PubMed

In this study, we sought to elucidate whether protocatechuic acid contributes to induce angiogenesis as well as its mechanisms. To this end, we examined the role of protocatechuic acid on human brain microvascular endothelial cell line (HBMEC) proliferation, invasion and tube formation in in vitro. For the study of mechanisms involved, the phosphoinositide 3 kinase (PI3K)-Akt inhibitor LY294002, the endothelial nitric oxide synthase (eNOS) inhibitor L-NAME, vascular endothelial growth factor (VEGF), antagonist sFlt-1 and VEGF receptor blocker SU-1498 were used. Proliferation of HBMEC was tested by MTT. Scratch adhesion test was used to assess the ability of invasion. A Matrigel tube formation assay was performed to test capillary tube formation ability. PI3K-Akt-eNOS-VEGF pathway activation in HBMEC was tested by Western blot. Our data suggested that protocatechuic acid induces angiogenesis in vitro by increasing proliferation, invasion and tube formation. VEGF expression was increasing by protocatechuic acid and counteracted by VEGF antagonist sFlt-1, LY294002 and L-NAME in HBMEC. Tube formation was increased by protocatechuic acid and counteracted by VEGF receptor blocker-SU1498, LY294002 and L-NAME. These data suggest that protocatechuic acid may be a candidate therapy for stroke recovery by promoting angiogenesis via a programmed PI3K/Akt/eNOS/VEGF signalling axis. PMID:23738793

Kang, Zechun; Zhu, Haibo; Jiang, Wanglin; Zhang, Shuping

2013-10-01

291

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

SciTech Connect

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.

Zordoky, Beshay N.M.; Anwar-Mohamed, Anwar; Aboutabl, Mona E. [Faculty of Pharmacy and Pharmaceutical Sciences, 3126 Dentistry/Pharmacy Centre, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada); El-Kadi, Ayman O.S., E-mail: aelkadi@pharmacy.ualberta.c [Faculty of Pharmacy and Pharmaceutical Sciences, 3126 Dentistry/Pharmacy Centre, University of Alberta, Edmonton, Alberta, T6G 2N8 (Canada)

2010-01-01

292

A MANUAL FOR THE REMOVAL, FIXATION AND PRESERVATION OF CETACEAN EARS  

E-print Network

Julie Arruda Biology Department Woods Hole Oceanographic Institution Woods Hole, Massachusetts..............................................................................................8 Sperm Whale (Physeter macrocephalus) Ear Removal.............................................11 Beaked Whale Ear Removal..............................................................................15

293

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

ERIC Educational Resources Information Center

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…

Varvarigou, Maria

2014-01-01

294

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

PubMed

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

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

2010-07-01

295

Mechanics of the exceptional anuran ear  

PubMed Central

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

Segenhout, Johannes M.; van Dijk, Pim

2008-01-01

296

Axonal Gradient of Arachidonic Acid-containing Phosphatidylcholine and Its Dependence on Actin Dynamics*  

PubMed Central

Phosphatidylcholine (PC) is the most abundant component of lipid bilayers and exists in various molecular forms, through combinations of two acylated fatty acids. Arachidonic acid (AA)-containing PC (AA-PC) can be a source of AA, which is a crucial mediator of synaptic transmission and intracellular signaling. However, the distribution of AA-PC within neurons has not been indicated. In the present study, we used imaging mass spectrometry to characterize the distribution of PC species in cultured neurons of superior cervical ganglia. Intriguingly, PC species exhibited a unique distribution that was dependent on the acyl chains at the sn-2 position. In particular, we found that AA-PC is enriched within the axon and is distributed across a proximal-to-distal gradient. Inhibitors of actin dynamics (cytochalasin D and phallacidin) disrupted this gradient. This is the first report of the gradual distribution of AA-PC along the axon and its association with actin dynamics. PMID:22207757

Yang, Hyun-Jeong; Sugiura, Yuki; Ikegami, Koji; Konishi, Yoshiyuki; Setou, Mitsutoshi

2012-01-01

297

Roles of renal cytochrome P450-dependent arachidonic acid metabolites in hypertension.  

PubMed

Cytochrome P450 represents the third metabolic pathway of arachidonic acid giving rise to several biologically active compounds, such as 19-HETE, 20-HETE and EETs and their corresponding DHETs. The kidney is the rich source of these metabolites which have some important biologic actions within the kidney. These metabolites have a wide and contrasting spectrum of biological and renal effects, from vasodilation to vasoconstriction and from inhibition to stimulation of Na-K-ATPase, their relative production rates may influence not only renal hemodynamics but also pro- and anti-hypertensive mechanisms of hypertension. There is increasing evidence that the abnormality of these metabolites in animal models of hypertension. However, sufficient evidence of the physiological and pathophysiological roles of hypertension in man is still lacking. PMID:1412450

Omata, K; Abe, K; Sheu, H L; Yoshida, K; Tsutsumi, E; Yoshinaga, K; Abraham, N G; Laniado-Schwartzman, M

1992-01-01

298

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

PubMed

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

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

1997-08-01

299

Acid-induced gelation of whey protein polymers: effects of pH and calcium concentration during polymerization  

Microsoft Academic Search

Heating whey protein dispersions (90°C for 15 min) at low ionic strength and pH values far from isoelectric point (pH>6.5) induced the formation of soluble polymers. The effect of mineral environment during heating on the hydrodynamic characteristics and acid-induced gelation properties of polymers was studied. Whey protein dispersions (80g\\/l) were denatured at different pH (6.5–8.5) and calcium concentrations (0–4mm) according

Michel Britten; Hélène J Giroux

2001-01-01

300

Comparative study on acid-induced gelation of myosin from Atlantic cod ( Gardus morhua) and burbot ( Lota lota)  

Microsoft Academic Search

Physicochemical and rheological properties of myosin from Atlantic cod and burbot during acid-induced gelation at room temperature (22–23°C) by d-gluconic acid-?-lactone (GDL) were monitored. Turbidity and particle size of both myosins increased and salt soluble content decreased when pH decreased, suggesting the formation of protein aggregates caused by acidification. The formation of disulphide bonds in myosin gelation was induced by

Siriporn Riebroy; Soottawat Benjakul; Wonnop Visessanguan; Ulf Erikson; Turid Rustad

2008-01-01

301

Roles of histamine receptors and oxyradicals in aggravation of acid-induced gastric haemorrhagic ulcers in endotoxaemic rats  

Microsoft Academic Search

We clarified the roles of histamine H1-, H2-, H3-receptors and oxyradicals in the exacerbation of acid-induced gastric haemorrhage and stomach ulcer in endotoxaemic rats\\u000a by measuring changes in gastric mucosal glutathione concentrations, lipid peroxide generation and histamine levels as well\\u000a as in luminal electrolytes and haemoglobin contents. Stomach ulcers were evaluated by morphological and histological examination.\\u000a Rats were deprived of

C. R. Hung; D.-Z. HSU

1998-01-01

302

Uric acid induces fat accumulation via generation of endoplasmic reticulum stress and SREBP-1c activation in hepatocytes.  

PubMed

Non-alcoholic fatty liver disease (NAFLD) is currently one of the most common types of chronic liver injury. Elevated serum uric acid is a strong predictor of the development of fatty liver as well as metabolic syndrome. Here we demonstrate that uric acid induces triglyceride accumulation by SREBP-1c activation via induction of endoplasmic reticulum (ER) stress in hepatocytes. Uric acid-induced ER stress resulted in an increase of glucose-regulated protein (GRP78/94), splicing of the X-box-binding protein-1 (XBP-1), the phosphorylation of protein kinase RNA-like ER kinase (PERK), and eukaryotic translation initiation factor-2? (eIF-2?) in cultured hepatocytes. Uric acid promoted hepatic lipogenesis through overexpression of the lipogenic enzyme, acetyl-CoA carboxylase 1 (ACC1), fatty acid synthase (FAS), and stearoyl-CoA desaturase 1 (SCD1) via activation of SREBP-1c, which was blocked by probenecid, an organic anion transport blocker in HepG2 cells and primary hepatocytes. A blocker of ER stress, tauroursodeoxycholic acid (TUDCA), and an inhibitor of SREBP-1c, metformin, blocked hepatic fat accumulation, suggesting that uric acid promoted fat synthesis in hepatocytes via ER stress-induced activation of SREBP-1c. Uric acid-induced activation of NADPH oxidase preceded ER stress, which further induced mitochondrial ROS production in hepatocytes. These studies provide new insights into the mechanisms by which uric acid stimulates fat accumulation in the liver. PMID:25111690

Choi, Yea-Jin; Shin, Hyun-Soo; Choi, Hack Sun; Park, Joo-Won; Jo, Inho; Oh, Eok-Soo; Lee, Kang-Yo; Lee, Byung-Hoon; Johnson, Richard J; Kang, Duk-Hee

2014-10-01

303

Prenatal Ultrasound Screening for External Ear Abnormality in the Fetuses  

PubMed Central

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

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

2014-01-01

304

Kainic acid-induced recurrent mossy fiber innervation of dentate gyrus GABAergic interneurons  

PubMed Central

Kainic acid-induced neuron loss in the hippocampal dentate gyrus may cause epileptogenic hyperexcitability by triggering the formation of recurrent excitatory connections among normally unconnected granule cells. We tested this hypothesis by assessing granule cell excitability repeatedly within the same awake rats at different stages of the synaptic reorganization process initiated by kainate-induced status epilepticus (SE). Granule cells were maximally hyperexcitable to afferent stimulation immediately after SE, and became gradually less excitable during the first month post-SE. The chronic epileptic state was characterized by granule cell hyperinhibition, i.e. abnormally increased paired-pulse suppression and an abnormally high resistance to generating epileptiform discharges in response to afferent stimulation. Focal application of the GABAA receptor antagonist bicuculline methiodide within the dentate gyrus abolished the abnormally increased paired-pulse suppression recorded in chronically hyperinhibited rats. Combined Timm staining and parvalbumin immunocytochemistry revealed dense innervation of dentate inhibitory interneurons by newly-formed, Timm-positive, mossy fiber terminals. Ultrastructural analysis by conventional- and post-embedding GABA immunocytochemical electron microscopy confirmed that abnormal mossy fiber terminals of the dentate inner molecular layer formed frequent asymmetrical synapses with inhibitory interneurons and with GABA-immunopositive dendrites, as well as with GABA-immunonegative dendrites of presumed granule cells. These results in chronically epileptic rats demonstrate that dentate granule cells are maximally hyperexcitable immediately after SE, prior to mossy fiber sprouting, and that synaptic reorganization following kainate-induced injury is temporally associated with GABAA receptor-dependent granule cell hyperinhibition, rather than an hypothesized progressive hyperexcitability. The anatomical data provide evidence of a possible anatomical substrate for the chronically hyperinhibited state. PMID:16385488

Sloviter, Robert S.; Zappone, Colin A.; Harvey, Brian D.; Frotscher, Michael

2008-01-01

305

Oleanolic acid induces relaxation and calcium-independent release of endothelium-derived nitric oxide  

PubMed Central

Background and purpose: The present study investigated the mechanisms by which oleanolic acid, a component of olive oil, increases release of nitric oxide (NO). Experimental approach: Measurements of isometric tension, NO concentration, or endothelial cell calcium were made in rat isolated mesenteric arteries. Immunoblotting for endothelial NOS (eNOS) and Akt kinase were performed in primary cultures of human umbilical vein endothelial cells (HUVECs). Key results: Oleanolic acid (3–30??M) evoked endothelium-dependent relaxations in noradrenaline-contracted rat superior and small mesenteric arteries. In rat superior mesenteric arteries, oleanolic acid induced simultaneous increases in NO concentration and relaxation, and these responses were inhibited by an inhibitor of NOS, asymmetric dimethyl-L-arginine (300??M) and by the NO scavenger, oxyhaemoglobin (10??M). Oleanolic acid-evoked NO increases were not reduced in Ca2+-free solution and in the presence of an inhibitor of endoplasmic reticulum calcium-ATPase, thapsigargin (1??M). Oleanolic acid evoked relaxation without changes in endothelial cell calcium, but decreased smooth muscle calcium in arterial segments. Oleanolic acid failed to increase calcium in HUVECs, but increased time-dependently phosphorylation of Akt kinase at Serine473 (Akt-Ser473) and eNOS at Serine1177 (eNOS-Ser1177), which was attenuated by inhibitors of phosphoinositide-3-kinase. Conclusions and implications: This study provides direct evidence that a component of olive oil, oleanolic acid, activated endothelium-dependent release of NO and decreased smooth muscle cell calcium followed by relaxation. The oleanolic acid-evoked endothelium-derived NO release was independent of endothelial cell calcium and involved phosphoinositide-3-kinase-dependent phosphorylation of Akt-Ser473 followed by phosphorylation of eNOS-Ser1177. PMID:18622409

Rodriguez-Rodriguez, R; Stankevicius, E; Herrera, M D; Østergaard, L; Andersen, M R; Ruiz-Gutierrez, V; Simonsen, U

2008-01-01

306

Bile Acid-Induced Arrhythmia Is Mediated by Muscarinic M2 Receptors in Neonatal Rat Cardiomyocytes  

PubMed Central

Background Intrahepatic cholestasis of pregnancy (ICP) is a common disease affecting up to 5% of pregnancies and which can cause fetal arrhythmia and sudden intrauterine death. We previously demonstrated that bile acid taurocholate (TC), which is raised in the bloodstream of ICP, can acutely alter the rate and rhythm of contraction and induce abnormal calcium destabilization in cultured neonatal rat cardiomyocytes (NRCM). Apart from their hepatic functions bile acids are ubiquitous signalling molecules with diverse systemic effects mediated by either the nuclear receptor FXR or by a recently discovered G-protein coupled receptor TGR5. We aim to investigate the mechanism of bile-acid induced arrhythmogenic effects in an in-vitro model of the fetal heart. Methods and Results Levels of bile acid transporters and nuclear receptor FXR were studied by quantitative real time PCR, western blot and immunostaining, which showed low levels of expression. We did not observe functional involvement of the canonical receptors FXR and TGR5. Instead, we found that TC binds to the muscarinic M2 receptor in NRCM and serves as a partial agonist of this receptor in terms of inhibitory effect on intracellular cAMP and negative chronotropic response. Pharmacological inhibition and siRNA-knockdown of the M2 receptor completely abolished the negative effect of TC on contraction, calcium transient amplitude and synchronisation in NRCM clusters. Conclusion We conclude that in NRCM the TC-induced arrhythmia is mediated by the partial agonism at the M2 receptor. This mechanism might serve as a promising new therapeutic target for fetal arrhythmia. PMID:20300620

Sheikh Abdul Kadir, Siti H.; Miragoli, Michele; Abu-Hayyeh, Shadi; Moshkov, Alexey V.; Xie, Qilian; Keitel, Verena; Nikolaev, Viacheslav O.; Williamson, Catherine; Gorelik, Julia

2010-01-01

307

The cumulus cell layer protects the bovine maturing oocyte against Fatty Acid-induced lipotoxicity.  

PubMed

Mobilization of fatty acids from adipose tissue during metabolic stress increases the amount of free fatty acids in blood and follicular fluid and is associated with impaired female fertility. In a previous report, we described the effects of the three predominant fatty acids in follicular fluid (saturated palmitate and stearate and unsaturated oleate) on oocyte maturation and quality. In the current study, the effects of elevated fatty acid levels on cumulus cells were investigated. In a dose-dependent manner, the three fatty acids induced lipid storage in cumulus cells accompanied by an enhanced immune labeling of perilipin-2, a marker for lipid droplets. Lipidomic analysis confirmed incorporation of the administered fatty acids into triglyceride, resulting in a 3- to 6-fold increase of triglyceride content. In addition, palmitate selectively induced ceramide formation, which has been implicated in apoptosis. Indeed, of the three fatty acids tested, palmitate induced reactive oxygen species formation, caspase 3 activation, and mitochondria deterioration, leading to degeneration of the cumulus cell layers. This effect could be mimicked by addition of the ceramide-C2 analog and could be inhibited by the ceramide synthase inhibitor fumonisin-B1. Interfering with the intactness of the cumulus cell layers, either by mechanical force or by palmitate treatment, resulted in enhanced uptake of lipids in the oocyte and increased radical formation. Our results show that cumulus cells act as a barrier, protecting oocytes from in vitro induced lipotoxic effects. We suggest that this protective function of the cumulus cell layers is important for the developmental competence of the oocyte. The relevance of our findings for assisted reproduction technologies is discussed. PMID:25297544

Lolicato, Francesca; Brouwers, Jos F; de Lest, Chris H A van; Wubbolts, Richard; Aardema, Hilde; Priore, Paola; Roelen, Bernard A J; Helms, J Bernd; Gadella, Bart M

2015-01-01

308

Distinct roles for Wnt-4 and Wnt-11 during retinoic acid-induced neuronal differentiation.  

PubMed

Retinoic acid and Wnt/?-catenin signals play important roles during neuronal differentiation but less is known about noncanonical Wnt signals in this context. We examined retinoic acid and Wnt signaling in two human embryonal carcinoma cell lines, NTERA-2 (clone D1), which undergoes neuronal differentiation in response to retinoic acid, and 2102Ep, which does not. Retinoic acid treatment inhibited ?-catenin/Tcf activity in NTERA-2 cells but not in 2102Ep cells. Inhibition occurred downstream of ?-catenin but did not involve competition between retinoic acid receptors and ?-catenin for binding to p300 or Tcf-4. Ectopic expression of FZD1 partially restored inhibition in 2102Ep cells, suggesting the involvement of Wnt ligands. Retinoic acid treatment of NTERA-2 cells induced the expression of Wnt-4 and Wnt-11, both of which were able to inhibit ?-catenin/Tcf activity. Wnt-4 and Wnt-11 were found at cell borders in islands of cells that expressed OCT4 and GFAP and were predominantly negative for Nestin, PAX6, and GATA6. Gene silencing of Wnt-4, but not Wnt-11, reduced retinoic acid downregulation of OCT4 and Nanog and upregulation of PAX6, ASCL1, HOXC5, and NEUROD1, suggesting that Wnt-4 promotes early neuronal differentiation. Gene expression analysis of NTERA-2 cells stably overexpressing Wnt-11 suggested that Wnt-11 potentiates retinoic acid induction of early neurogenesis. Consistent with this, overexpression of Wnt-11 maintained a population of proliferating progenitor cells in cultures treated with retinoic acid for several weeks. These observations highlight the distinct roles of two noncanonical Wnts during the early stages of retinoic acid-induced neuronal differentiation. PMID:21280163

Elizalde, Carina; Campa, Victor M; Caro, Mercedes; Schlangen, Karin; Aransay, Ana María; Vivanco, Maria dM; Kypta, Robert M

2011-01-01

309

Human sweet taste receptor mediates acid-induced sweetness of miraculin  

PubMed Central

Miraculin (MCL) is a homodimeric protein isolated from the red berries of Richadella dulcifica. MCL, although flat in taste at neutral pH, has taste-modifying activity to convert sour stimuli to sweetness. Once MCL is held on the tongue, strong sweetness is sensed over 1 h each time we taste a sour solution. Nevertheless, no molecular mechanism underlying the taste-modifying activity has been clarified. In this study, we succeeded in quantitatively evaluating the acid-induced sweetness of MCL using a cell-based assay system and found that MCL activated hT1R2-hT1R3 pH-dependently as the pH decreased from 6.5 to 4.8, and that the receptor activation occurred every time an acid solution was applied. Although MCL per se is sensory-inactive at pH 6.7 or higher, it suppressed the response of hT1R2-hT1R3 to other sweeteners at neutral pH and enhanced the response at weakly acidic pH. Using human/mouse chimeric receptors and molecular modeling, we revealed that the amino-terminal domain of hT1R2 is required for the response to MCL. Our data suggest that MCL binds hT1R2-hT1R3 as an antagonist at neutral pH and functionally changes into an agonist at acidic pH, and we conclude this may cause its taste-modifying activity. PMID:21949380

Koizumi, Ayako; Tsuchiya, Asami; Nakajima, Ken-ichiro; Ito, Keisuke; Terada, Tohru; Shimizu-Ibuka, Akiko; Briand, Loïc; Asakura, Tomiko; Misaka, Takumi; Abe, Keiko

2011-01-01

310

3D ear identification based on sparse representation.  

PubMed

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

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

2014-01-01

311

Human fetal inner ear involvement in congenital cytomegalovirus infection  

PubMed Central

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

2013-01-01

312

A Case of Atypical Granuloma Annulare Involving Both Ears  

PubMed Central

We report a rare case of granuloma annulare (GA), affecting both ear antihelixes, in a 28-year old male patient that presented with a 1-year history of non-tender, firm, skin-colored, 1~5 mm papules on both ear antihelixes. There was no history of trauma. An excisional biopsy specimen taken from one of the lesions of the right ear revealed infiltration of histiocytes and lymphocytes around a zone of collagen alteration in the dermis. Based on the clinical and pathological findings, the patient was diagnosed with a rare case of bilateral GA of both antihelixes; this is the first report in the Korean dermatology literature. PMID:20523836

Kim, Jin Gu; Lee, Seung Hun

2009-01-01

313

Red ear syndrome: case report and review of the literature.  

PubMed

Red ear syndrome (RES) is characterized by the attack-like occurrence of erythema, edema and dysesthesia of one or less frequently both ears. We report the case of a 31-year-old woman with stabbing pain and marked erythema and discrete edema of one ear, existing for 4 months, occasionally accompanied by burning and local hyperhidrosis. Differential diagnoses such as perichondritis, contact dermatitis, erysipelas and other infections were ruled out. Based on her history, the clinical pattern and the unremarkable further diagnostics, we diagnosed RES. A review of the literature is included. PMID:21985901

Eismann, Regina; Gaul, Charly; Wohlrab, Johannes; Marsch, Wolfgang Christian; Fiedler, Eckhard

2011-01-01

314

Tumors and tumorlike lesions of dog and cat ears.  

PubMed

Bacterial and fungal otitis constitutes most ear disease in companion animals. However, a wide spectrum of infectious and noninfectious disease processes involve the structures of the ear and are of primary diagnostic consideration in cases of recurrent otitis or those refractive to traditional treatments. This article discusses several common to reasonably rare neoplastic and nonneoplastic space-occupying lesions of the external, middle, and internal ear. Although some conditions present as unique entities, many present similar to or concurrent with otitis, and should be considered in cases of clinically unresponsive otitis. PMID:23122175

Sula, Mee Ja M

2012-11-01

315

Red ear syndrome and auricular erythromelalgia: the same condition?  

PubMed

Several cases of relapsing attacks during which the ear becomes red and patients experience a burning sensation have been reported in the literature. This combination of symptoms has been described as 'red ear syndrome' (RES). We report on a 7-year-old boy who had episodes of reddening, swelling and a burning sensation in one ear with local hyperthermia persisting for 3 years. The differential diagnosis included RES and erythromelalgia, as isolated auricular variants of erythromelalgia have been described and the symptoms are difficult to distinguish from RES. In this report, we discuss the similarities and differences between RES and erythromelalgia. PMID:19489849

Brill, T J; Funk, B; Thaçi, D; Kaufmann, R

2009-12-01

316

Evolution of Gravity Receptors in the Ear  

NASA Technical Reports Server (NTRS)

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.

Popper, Arthur N. (Principal Investigator)

1996-01-01

317

Wideband Power Reflectance and Power Transmittance as Tools for Assessing Middle-Ear Function  

E-print Network

44 Wideband Power Reflectance and Power Transmittance as Tools for Assessing Middle-Ear Function using otoacoustic emissions can have high false positive rates, due to temporary middle-ear and outer-ear is limited, uncomfortable, and unreliable in young ears. By incorporating wideband acoustic power flow

Allen, Jont

318

Q What is a unilateral hearing loss? What causes a hearing loss in only one ear?  

E-print Network

Q· What is a unilateral hearing loss? · What causes a hearing loss in only one ear? · Will the hearing in my child's better ear get worse? · Why would my child have trouble hearing if one ear has normal hearing? · Will my child benefit from wearing a hearing aid in the ear with the hearing loss

O'Toole, Alice J.

319

ON A MATROID DEFINED BY EAR-DECOMPOSITIONS OF GRAPHS ZOLTAN SZIGETI *  

E-print Network

ON A MATROID DEFINED BY EAR-DECOMPOSITIONS OF GRAPHS ZOLT´AN SZIGETI * December 1, 1995 A-edge­connected graphs this value equals the minimum number (G) of even ears in ear­decompositions of G that G is 2-edge­ connected. Let G = (V, E) be an undirected, 2-edge­connected graph. An ear

Szigeti, Zoltán

320

Reflectance in ME disorders 1 Running head: REFLECTANCE IN MIDDLE-EAR DISORDERS  

E-print Network

Reflectance in ME disorders 1 Running head: REFLECTANCE IN MIDDLE-EAR DISORDERS Wideband energy reflectance measurements in adults with middle-ear disorders M. Patrick Feeney University of Washington with a variety of middle-ear disorders. The ER results from nine participants with middle-ear disorders and one

Allen, Jont

321

Have WISE EARS! for Life: Protect Yourself and Your Family from Noise-Induced Hearing Loss  

MedlinePLUS

Home Health Info Hearing, Ear Infections, and Deafness Have WISE EARS! for life Have WISE EARS! for life Protect yourself and your family from ... Loud bookmark . Top How can I protect my hearing in noisy situations? Wear ear plugs or special earmuffs when you are exposed ...

322

Sonographic Measurement of Fetal Ear Length in Turkish Women with a Normal Pregnancy  

PubMed Central

Background: Abnormal fetal ear length is a feature of chromosomal disorders. Fetal ear length measurement is a simple measurement that can be obtained during ultrasonographic examinations. Aims: To develop a nomogram for fetal ear length measurements in our population and investigate the correlation between fetal ear length, gestational age, and other standard fetal biometric measurements. Study Design: Cohort study. Methods: Ear lengths of the fetuses were measured in normal singleton pregnancies. The relationship between gestational age and fetal ear length in millimetres was analysed by simple linear regression. In addition, the correlation of fetal ear length measurements with biparietal diameter, head circumference, abdominal circumference, and femur length were evaluated.Ear length measurements were obtained from fetuses in 389 normal singleton pregnancies ranging between 16 and 28 weeks of gestation. Results: A nomogram was developed by linear regression analysis of the parameters ear length and gestational age. Fetal ear length (mm) = y = (1.348 X gestational age)?12.265), where gestational ages is in weeks. A high correlation was found between fetal ear length and gestational age, and a significant correlation was also found between fetal ear length and the biparietal diameter (r=0.962; p<0.001). Similar correlations were found between fetal ear length and head circumference, and fetal ear length and femur length. Conclusion: The results of this study provide a nomogram for fetal ear length. The study also demonstrates the relationship between ear length and other biometric measurements.

Özdemir, Mucize Eriç; Uzun, I??l; Karahasano?lu, Ay?e; Aygün, Mehmet; Ak?n, Hale; Yaz?c?o?lu, Fehmi

2014-01-01

323

Feature-level fusion method based on KFDA for multimodal recognition fusing ear and profile face  

Microsoft Academic Search

A novel method of feature-level fusion based on kernel Fisher discriminant analysis (KFDA) is proposed and applied to fusion of ear and profile face biometrics in this paper. Ear recognition is proved to be a new and promising authentication technique. Because of ear's special physiological structure and location, it is reasonable to combine ear with profile face for recognition in

Xiao-Na Xu; Zhi-Chun Mu; Li Yuan

2007-01-01

324

Modeling Directional Brightness Temperature of the Winter Wheat Canopy at the Ear Stage  

Microsoft Academic Search

The ear is the top layer of mature wheat and has very different geometric and thermal characteristics from that of leaves. Compared to the directional brightness temperature (DBT) of wheat canopy without ears, the DBT at the ear stage has specific features, and the ear effects could not be explained by previous models. This paper proposes a hybrid geometric optical

Yongming Du; Qinhuo Liu; Liangfu Chen; Qiang Liu; Tao Yu

2007-01-01

325

Prediction of the sound pressure at the ear drum for open fittings  

E-print Network

Prediction of the sound pressure at the ear drum for open fittings T. Sankowsky-Rothea , M. Blaua of hearing aids requires knowledge of the sound pressure generated at the ear drum. Traditionally, the sound pressure at the ear drum is estimated by the use of a model of an average ear canal (e.g. a coupler

Paris-Sud XI, Université de

326

Nanomedicine strategies for drug delivery to the ear.  

PubMed

The highly compartmentalized anatomy of the ear aggravates drug delivery, which is used to combat hearing-related diseases. Novel nanosized drug vehicles are thought to overcome the limitations of classic approaches. In this article, we summarize the nanotechnology-based efforts involving nano-objects, such as liposomes, polymersomes, lipidic nanocapsules and poly(lactic-co-glycolic acid) nanoparticles, as well as nanocoatings of implants to provide an efficient means for drug transfer in the ear. Modern strategies do not only enhance drug delivery efficiency, in the inner ear these vector systems also aim for specific uptake into hair cells and spiral ganglion neurons. These novel peptide-mediated strategies for specific delivery are reviewed in this article. Finally, the biosafety of these vector systems is still an outstanding issue, since long-term application to the ear has not yet been assessed. PMID:23837855

Pritz, Christian Oliver; Dudás, József; Rask-Andersen, Helge; Schrott-Fischer, Anneliese; Glueckert, Rudolf

2013-07-01

327

Energy extraction from the biologic battery in the inner ear  

E-print Network

Endocochlear potential (EP) is a battery-like electrochemical gradient found in and actively maintained by the inner ear [superscript 1, 2]. Here we demonstrate that the mammalian EP can be used as a power source for ...

Bandyopadhyay, Saurav

328

21 CFR 344.12 - Ear drying aid active ingredient.  

Code of Federal Regulations, 2010 CFR

...Ingredients § 344.12 Ear drying aid active ingredient. The active ingredient of the product consists of isopropyl alcohol 95 percent in an anhydrous glycerin 5 percent base. [65 FR 48905, Aug. 10,...

2010-04-01

329

Making an Effort to Listen: Mechanical Amplification in the Ear  

PubMed Central

The inner ear’s performance is greatly enhanced by an active process defined by four features: amplification, frequency selectivity, compressive nonlinearity, and spontaneous otoacoustic emission. These characteristics emerge naturally if the mechanoelectrical transduction process operates near a dynamical instability, the Hopf bifurcation, whose mathematical properties account for specific aspects of our hearing. The active process of non-mammalian tetrapods depends upon active hair-bundle motility, which emerges from the interaction of negative hair-bundle stiffness and myosin-based adaptation motors. Taken together, these phenomena explain the four characteristics of the ear’s active process. In the high-frequency region of the mammalian cochlea, the active process is dominated instead by the phenomenon of electromotility, in which the cell bodies of outer hair cells extend and contract as the protein prestin alters its membrane surface area in response to changes in membrane potential. PMID:18760690

Hudspeth, A. J.

2009-01-01

330

Get Smart: Know When Antibiotics Work - Ear Infections  

MedlinePLUS

... Antibiotic Use Respiratory Illnesses Sinus Infection Sore Throat Common Cold and Runny Nose Ear Infections Bronchitis (Chest Cold) ... Tips Appropriate Treatment Summary Cough Illness/Bronchitis The Common Cold Otitis Media Pharyngitis: Treat Only Proven GAS Online ...

331

Penetrating middle ear trauma: a report of 2 cases.  

PubMed

Penetrating middle ear injury can result in hearing loss, vertigo, and facial nerve injury. We describe the cases of 2 children with penetrating trauma to the right ear that resulted in ossicular chain disruption; one injury was caused by cotton-tipped swabs and the other by a wooden matchstick. Symptoms in both children included hearing loss and otalgia; in addition, one child experienced ataxia and the other vertigo. Physical examination in both cases revealed a perforation in the posterosuperior quadrant of the tympanic membrane and visible ossicles. Audiometry identified a moderate conductive hearing loss in one child and a mild sensorineural hearing loss in the other. Both children underwent middle ear exploration and reduction of a subluxed stapes. We discuss the diagnosis, causes, and management of penetrating middle ear trauma. To reduce the morbidity associated with these traumas, otologic surgeons should act promptly and be versatile in choosing methods of repairing ossicular chain injuries. PMID:15742770

Neuenschwander, Michael C; Deutsch, Ellen S; Cornetta, Anthony; Willcox, Thomas O

2005-01-01

332

Division of Earth Sciences (EAR) -- Dear Colleague Letter  

NSF Publications Database

... Date : May 12, 1993 File : nsf9361 DIVISION OF EARTH SCIENCES NSF 93-61 (New) Dear Colleague: The ... National Science Foundation's Division of Earth Sciences (EAR) is 1 June 1993. This will be the ...

333

Music to our ears During a visit to Santa  

E-print Network

#12;Music to our ears During a visit to Santa Cruz coordinated by UCSC's Arts & Lectures, Wynton Marsalis helped the young--and young at heart--celebrate the timeless music of Duke Ellington. Features

California at Santa Cruz, University of

334

How minute sooglossid frogs hear without a middle ear  

PubMed Central

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

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

2013-01-01

335

Green laser light activates the inner ear  

NASA Astrophysics Data System (ADS)

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-?m 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 ?J/pulse) and remained consistent even after 30 minutes of continuous stimulation at 13 ?J, 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.

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

336

Hydration-state change of horse heart cytochrome c corresponding to trifluoroacetic-acid-induced unfolding.  

PubMed

We investigate the hydration state of horse-heart cytochrome c (hh cyt c) in the unfolding process induced by trifluoroacetic acid (TFA). The conformation of hh cyt c changes from the native (N) state (2.9 < pH < 6.0) to the acid-unfolded (U(A)) state (1.7 < pH < 2.0) to the acid-induced molten globule (A) state (pH ?1.2). Hydration properties of hh cyt c during this process are measured at 20°C by high-resolution dielectric relaxation (DR) spectroscopy, UV-vis absorbance, and circular dichroism spectroscopy. Constrained water of hh cyt c is observed at every pH as an ?5-GHz Debye component (DC) (DR time, ?(D) ?30 ps) and its DR amplitude (DRA) is increased by 77% upon N-to-U(A) transition, when pH changes from 6.0 to 2.0. Even in the N state, the DRA of the constrained-water component is found to be increased by 22% with decreasing pH from 6.0 to 2.9, suggesting an increase in the accessible surface area of native hh cyt c. Moreover, hypermobile water around native hh cyt c is detected at pH 6.0 as a 19-GHz DC (?(D) ? 8.4 ps 

Miyashita, Yusuke; Wazawa, Tetsuichi; Mogami, George; Takahashi, Satoshi; Sambongi, Yoshihiro; Suzuki, Makoto

2013-01-01

337

Polychlorinated biphenyls induce arachidonic acid release in human platelets in a tamoxifen sensitive manner via activation of group IVA cytosolic phospholipase A2-?  

PubMed Central

Polychlorinated biphenyls (PCBs) are stable compounds commonly found in nature as environmental pollutants. PCBs can affect the endocrine function of hormones such as steroid-hormones. Also, PCBs are known to be inducers of arachidonic acid release in various cells. We report, here, the effects of PCBs on eicosanoid formation, arachidonic acid release and cytosolic phospholipase A2-?(cPLA2-?) activation in human platelets. Ortho-substituted PCBs induced a time and dose-dependent release of arachidonic acid and the concomitant formation of 12(S)-hydroxy-5,8-cis-10-trans-14-cis-eicosatetraenoic acid (12-HETE) and 12(S)-hydroxy-5-cis-8,10-trans-heptadecatrienoic acid (12-HHT) in human platelets. The release of arachidonic acid and the formation of 12-HETE was completely blocked by the cPLA2-? inhibitors AACOCF3 or pyrrolidine-1. PCB-treatment of platelets demonstrated that the cPLA2-? protein as well as PLA2 activity translocated to the membrane fraction, independent of a rise in intracellular Ca2+. Furthermore, electrophoretic gel mobility shift analysis of cPLA2-? on SDS-PAGE demonstrated a PCB-dependent phosphorylation of cPLA2-?. The effects of 17?-estradiol and two structurally unrelated anti-estrogens, nafoxidin and tamoxifen on PCB-induced arachidonic acid release in platelets were also investigated. Both nafoxidin and tamoxifen inhibited PCB-induced arachidonic acid release as well as 12-HETE and 12-HHT formation. Interestingly, platelets incubated with PCBs did not aggregate despite the fact that robust release of arachidonic acid was observed. In summary, these results demonstrate that certain PCBs induce activation of cPLA2-? independent of a rise in intracellular calcium and a robust release of arachidonic acid release with resulting eicosanoid formation in human platelets. PMID:16290172

Forsell, Pontus K.A.; Olsson, Anders O.; Andersson, Erik; Nallan, Laxman; Gelb, Michael H.

2008-01-01

338

Blackbird and Starling Feeding Behavior on Ripening Corn Ears1  

Microsoft Academic Search

The behavior of red-winged blackbirds {Agelaius phoemcei\\/s), common grackles (Quiscalus quiscula), brown-headed cowbirds (Molothrus ater), and juvenile European starlings (Sturnus vulgaris) feeding on ears of corn was studied in an aviary. The species differed significantly in their propensity to attack (penetrate the husk and feed on kernels) ears of corn. Redwings and starlings were more active attackers than grackles and

GLEN E. BERNHARDT; LYNDA VAN ALLSBURG; RICHARD A. DOLBEER

339

Comparison between cartilage and soft tissue ear piercing complications  

Microsoft Academic Search

Purpose: Despite growing interest in cosmetic piercing, a detailed evaluation of associated medical complications is lacking.Materials and Methods: A questionnaire addressing ear, nose, and other body parts piercing was anonymously presented to 1,000 nurses at a major Midwestern teaching hospital, and responses were obtained from 552.Results: One hundred sixty (35%) of the 452 nurses who had an ear pierced reported

Timothy C. Simplot; Henry T. Hoffman

1998-01-01

340

Differential Senescence of Maize Hybrids following Ear Removal 1  

PubMed Central

In conjunction with a study of the effects of ear removal on the senescence of whole maize (Zea mays L.) plants, visual symptoms and associated changes in constituent contents and activities of a selected leaf (first leaf above the ear) were determined. Leaves were sampled from field-grown eared and earless Pioneer brand 3382, B73 × Mo17, and Farm Services brand 854 maize hybrids at nine times during the grainfilling period. Visual symptoms indicated the following sequence and rate of senescence: earless B73 × Mo17 > earless P3382 » eared B73 × Mo17 » eared P3382 ? earless FS854 > eared FS854. All earless hybrids showed increases in leaf dry weight and sugar content; however, the increases were transitory for P3382 and B73 × Mo17, but continuous throughout the grain-filling period for FS854, indicative of continued photosynthetic activity of the latter. All earless hybrids exhibited similar and transitory starch accumulation patterns. Thus, FS854 was an exception to the concept that carbohydrate accumulation accelerates leaf senescence. Ear removal resulted in accelerated losses of reduced N, phosphoenolpyruvate and ribulose bisphosphate carboxylases, phosphorus, chlorophyll, nitrate reductase activity, and moisture for P3382 and B73 × Mo17 plants. In contrast, the loss of all components (except phosphorus) was similar for the selected leaf of earless and eared FS854. Although the loss of nitrate reductase activity, reduced N, and carboxylating enzymes accurately reflected the development of senescence of the selected leaf, the rate of net loss of reduced N and carboxylating enzymes appeared to be regulated. We deduced that the rate of flux of N into the leaf was a factor in regulating the differing rates of senescence observed for the six treatments; however, we cannot rule out the possibility of concurrent influence of growth regulators or other metabolites. Images Fig. 2 PMID:16663424

Crafts-Brandner, Steven J.; Below, Frederick E.; Wittenbach, Vernon A.; Harper, James E.; Hageman, Richard H.

1984-01-01

341

[Common infections of the ear, nose, and throat].  

PubMed

Infectious diseases of the ear, nose and throat are common reasons why patients visit their family physician. Therefore, the aim of this mini-review is to give an overview of the most important and frequent infectious diseases of the ear, nose and throat, the appropriate diagnostic measurements and therapy with relevance for the family physician. Most of these infectious diseases can be treated by the family physician and do not necessarily need to be seen by an ENT-specialist. PMID:25146944

Weber, Claudia Sandra; Kleinjung, Tobias

2014-08-20

342

Scalp-Ear-Nipple Syndrome: A Case Report  

PubMed Central

The scalp-ear-nipple (SEN) syndrome is an infrequent congenital disease. Its main features are scalp defects, malformed ears, and absence of nipples. Most of the reported cases are autosomal dominant. We report on a patient suffering SEN syndrome with possible autosomal recessive inheritance. It is concluded that SEN syndrome should be recognized as an entity with genetic heterogeneity once there is evidence of different genetic manner of inheritance described in this disease. PMID:24660003

Morales-Peralta, Estela; Andrés, Vivian; Campillo Betancourt, Dainé

2014-01-01

343

2-Oxoamide inhibitors of phospholipase A2 activity and cellular arachidonate release based on dipeptides and pseudodipeptides  

PubMed Central

A series of 2-oxoamides based on dipeptides and pseudodipeptides were synthesized and their activities toward two human intracellular phospholipases A2 (GIVA cPLA2 and GVIA iPLA2) and one human secretory phospholipase A2 (GV sPLA2) were evaluated. Derivatives containing a free carboxyl group are selective GIVA cPLA2 inhibitors. A derivative based on the ethyl ester of an ether pseudodipeptide is the first 2-oxoamide, which preferentially inhibits GVIA iPLA2. The effect of 2-oxoamides on the generation of arachidonic acid from RAW 264.7 macrophages was also studied and it was found that selective GIVA cPLA2 inhibitors preferentially inhibited cellular arachidonic acid release; one pseudodipeptide gave an IC50 value of 2 ?M. PMID:19443224

Barbayianni, Efrosini; Stephens, Daren; Grkovich, Andrej; Magrioti, Victoria; Hsu, Yuan-Hao; Cotton, Naomi; Dolatzas, Panagiotis; Kalogiannidis, Dimitrios; Dennis, Edward A.; Kokotos, George

2009-01-01

344

Glutamate release evoked by glutamate receptor agonists in cultured chick retina cells: modulation by arachidonic acid.  

PubMed

We studied the effect of ionotropic glutamate receptor agonists on the release of endogenous glutamate or of [3H]D-aspartate from reaggregate cultures (retinospheroids) or from monolayer cultures of chick retinal cells, respectively. Kainate increased the fluorescence ratio of the Na+ indicator SBFI and stimulated a dose-dependent release of glutamate in low (0.1 mM) Ca2+ medium, as measured using a fluorometric assay. Under the same experimental conditions, the release evoked by N-methyl-D-aspartate (NMDA; 400 microM) was about half of that evoked by the same kainate concentration; alpha-amino-3-hydroxy-5-methyl-4-isoxasolepropionic acid (AMPA; 400 microM) did not trigger a significant response. In the presence of 1 mM CaCl2, all of the agonists increased the [Ca2+]i, as determined with the fluorescence dye Indo-1, but the glutamate release evoked by NMDA and kainate was significantly lower than that measured in 0.1 mM CaCl2 medium. Inhibition by Ca2+ of the kainate-stimulated release of glutamate was partially reversed by the phospholipase A2 inhibitor oleiloxyethyl phosphorylcholine (OPC), suggesting that the effect was mediated by the release of arachidonic acid, which inhibits the glutamate carrier. Accordingly, kainate, NMDA, and AMPA stimulated a Ca(2+)-dependent release of [3H]arachidonic acid, and the direct addition of the exogenous fatty acid to the medium decreased the release of glutamate evoked by kainate in low (0.1 mM) CaCl2 medium. In monolayer cultures, we showed that NMDA, kainate, and AMPA also stimulated the release of [3H]D-aspartate, but in this case release in the presence of 1 mM CaCl2 was significantly higher than that evoked in media with no added Ca2+. The ranking order of efficacy for stimulation of Ca(2+)-dependent release of [3H]D-aspartate was NMDA > > kainate > AMPA. PMID:8739156

Duarte, C B; Santos, P F; Sánchez-Prieto, J; Carvalho, A P

1996-05-15

345

2-Hydroxy Arachidonic Acid: A New Non-Steroidal Anti-Inflammatory Drug  

PubMed Central

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

Lopez, Daniel H.; Fiol-deRoque, Maria A.; Noguera-Salvà, Maria A.; Terés, Silvia; Campana, Federica; Piotto, Stefano; Castro, José A.; Mohaibes, Raheem J.; Escribá, Pablo V.; Busquets, Xavier

2013-01-01

346

Computed tomography features of middle ear cholesteatoma in dogs.  

PubMed

We describe the computed tomography (CT) findings in 11 dogs with middle ear cholesteatoma. The cholesteatoma appeared as an expansile tympanic cavity mass with a mean attenuation value of 55.8 +/- 4.2 Hounsfield units. There was no appreciable contrast enhancement of the tympanic bulla contense but ring enhancement was seen in four dogs. Due to the slow progressive growth, the lesion causes severe bone changes at the contour of the tympanic bulla, including osteolysis, osteoproliferation and osteosclerosis, expansion of the tympanic cavity, and sclerosis or osteoproliferation of the ipsilateral temporomandibular joint and paracondylar process. Cholesteatoma can cause lysis of the petrosal part of the temporal bone, leading to intracranial complications. Although not definitive, CT provides useful information for distinguishing a middle ear cholesteatoma from otitis media and neoplasia. In otitis media, enlargement of the tympanic cavity is not routinely observed. In tumors that primarily affect the middle or inner ear, the predominant signs are lysis of the contour of the tympanic bulla or the petrosal part of the temporal bone, soft tissue swelling around the middle ear and marked contrast enhancement. In tumors that arise from the external ear, a soft tissue mass is visible within the external acusticus meatus, and the middle ear is only involved secondarily. PMID:20806867

Travetti, Olga; Giudice, Chiara; Greci, Valentina; Lombardo, Rocco; Mortellaro, Carlo Maria; Di Giancamillo, Mauro

2010-01-01

347

Auditory Brainstem Circuits That Mediate the Middle Ear Muscle Reflex  

PubMed Central

The middle ear muscle (MEM) reflex is one of two major descending systems to the auditory periphery. There are two middle ear muscles (MEMs): the stapedius and the tensor tympani. In man, the stapedius contracts in response to intense low frequency acoustic stimuli, exerting forces perpendicular to the stapes superstructure, increasing middle ear impedance and attenuating the intensity of sound energy reaching the inner ear (cochlea). The tensor tympani is believed to contract in response to self-generated noise (chewing, swallowing) and nonauditory stimuli. The MEM reflex pathways begin with sound presented to the ear. Transduction of sound occurs in the cochlea, resulting in an action potential that is transmitted along the auditory nerve to the cochlear nucleus in the brainstem (the first relay station for all ascending sound information originating in the ear). Unknown interneurons in the ventral cochlear nucleus project either directly or indirectly to MEM motoneurons located elsewhere in the brainstem. Motoneurons provide efferent innervation to the MEMs. Although the ascending and descending limbs of these reflex pathways have been well characterized, the identity of the reflex interneurons is not known, as are the source of modulatory inputs to these pathways. The aim of this article is to (a) provide an overview of MEM reflex anatomy and physiology, (b) present new data on MEM reflex anatomy and physiology from our laboratory and others, and (c) describe the clinical implications of our research. PMID:20870664

Mukerji, Sudeep; Windsor, Alanna Marie; Lee, Daniel J.

2010-01-01

348

Structural insight into the detrimental effects of arachidonic acid and its metabolites on the production of ?-amyloid peptides and plaques  

Microsoft Academic Search

Inflammation is believed to be integral to the pathogenesis of Alzheimer's disease (AD). Arachidonic acid (AA) is the most important omega-6 fatty acid and a mediator of inflammatory pathways. High-sensitivity enzyme linked immunosorbent assay shows that AA and its various metabolites; prostaglandins, thromboxanes, and leukotriene B4 resulted in significantly higher secretion of both Abeta40 and 42 peptides. A combination of

Zareen Amtul; Markus Uhrig; Lin Wang; Richard F. Rozmahel; Konrad Beyreuther

349

Arachidonic acid inhibits lipogenic gene expression in 3T3-L1 adipocytes through a prostanoid pathway  

Microsoft Academic Search

This report examines the effect of polyunsatu- rated fatty acids (PUFA) on lipogenic gene expression in cultured 3T3-L1 adipocytes. Arachidonic acid (20:4, n-6) and eicosapentaenoic acid (20:5, n-3) suppressed mRNAs encoding fatty acid synthase (FAS) and S14, but had no ef- fect on b -actin. Using a clonal adipocyte cell line containing a stably integrated S14CAT fusion gene, oleic acid

Michelle K. Mater; David Pan; W. G. Bergen; Donald B. Jump

350

Molecular dynamics simulations of arachidonic acid complexes with COX-1 and COX-2: insights into equilibrium behavior.  

PubMed

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

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

2006-03-14

351

Arachidonic acid increases matrix metalloproteinase 9 secretion and expression in human monocytic MonoMac 6 cells  

Microsoft Academic Search

BACKGROUND: Dietary fatty acids may modulate inflammation in macrophages of the atherosclerotic plaque, affecting its stability. The n-6 polyunsaturated fatty acid (PUFA) arachidonic acid (AA) generally promotes inflammation, while the PUFAs of the n-3 series eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA) and docosahexaenoic acid (DHA) are considered anti-inflammatory. We determined how these PUFAs influence MMP-9 expression and secretion by the

Tiina Solakivi; Tarja Kunnas; Satu Kärkkäinen; Olli Jaakkola; Seppo T Nikkari

2009-01-01

352

Chronic Carbamazepine Administration Attenuates Dopamine D 2 -like Receptor-Initiated Signaling via Arachidonic Acid in Rat Brain  

Microsoft Academic Search

Observations that dopaminergic antagonists are beneficial in bipolar disorder and that dopaminergic agonists can produce mania\\u000a suggest that bipolar disorder involves excessive dopaminergic transmission. Thus, mood stabilizers used to treat the disease\\u000a might act in part by downregulating dopaminergic transmission. In agreement, we reported that dopamine D2-like receptor mediated signaling involving arachidonic acid (AA, 20:4n?6) was downregulated in rats chronically

Mireille Basselin; Lisa Chang; Mei Chen; Jane M. Bell; Stanley I. Rapoport

2008-01-01

353

Chronic fluoxetine increases cytosolic phospholipase A 2 activity and arachidonic acid turnover in brain phospholipids of the unanesthetized rat  

Microsoft Academic Search

Rationale  Fluoxetine is used to treat unipolar depression and is thought to act by increasing the concentration of serotonin (5-HT) in the synaptic cleft, leading to increased serotonin signaling. The 5-HT2A\\/2C receptor subtypes are coupled to a phospholipase A2 (PLA2). We hypothesized that chronic fluoxetine would increase the brain activity of PLA2 and the turnover rate of arachidonic acid (AA) in

Ho-Joo Lee; Jagadeesh S. Rao; Renee N. Ertley; Lisa Chang; Stanley I. Rapoport; Richard P. Bazinet

2007-01-01

354

Arachidonic, 5, 11, 14, 17-eicosatetraenoic and related acids in plants—Identification of unsaturated fatty acids  

Microsoft Academic Search

Arachidonic and related fatty acids which normally are found only in animals or microorganisms have been isolated and identified\\u000a from several mosses and ferns. Fatty acids with a double bond in position 5, separated by more than one methylene group from\\u000a other double bonds, have been found inGinkgo biloba andEquisetum. Analyses of fatty acids from numberous plants, in particular their

Hermann Schlenk; Joanne L. Gellerman

1965-01-01

355

Alterations of concentrations of calcium and arachidonic acid and agglutinations of microfilaments in host cells during Toxoplasma gondii invasion  

Microsoft Academic Search

Toxoplasma gondii (T. gondii) invasion of host cells is a complicated process of interaction between parasites and host cells. In the present study we investigated the alterations of free Ca2+ concentration ([Ca2+]i) and cytoskeletons in phagocytic and non-phagocytic host cells and arachidonic acid (AA) concentration in cells supernatant during T. gondii invasion. T. gondii invasion induced significant elevation of intracellular

Liwei Li; Xunde Li; Jie Yan

2008-01-01

356

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

PubMed Central

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

2014-01-01

357

Chronic cigarette smoke exposure adversely alters /sup 14/C-arachidonic acid metabolism in rat lungs, aortas and platelets  

SciTech Connect

Male rats were exposed to freshly generated cigarette smoke once daily, 5 times a week for 10 weeks. Inhalation of smoke was verified by elevated carboxyhemoglobin in blood sampled immediately after smoke exposure and by increased lung aryl hydrocarbon hydroxylase activity 24 hours after the last smoke exposure. Aortic rings isolated from smoke-exposed rats synthesized less prostacyclin (PGI2) from /sup 14/C-arachidonic acid than rings from sham rats. Platelets from smoke-exposed rats synthesized more thromboxane (TXA2) from /sup 14/C-arachidonic acid than platelets from room controls but not those from sham rats. Lung microsomes from smoke-exposed rats synthesized more TXA2 and had a lower PGI2/TXA2 ratio than lung microsomes from room controls and shams. It is concluded that chronic cigarette smoke exposure alters arachidonic acid metabolism in aortas, platelets and lungs in a manner resulting in decreased PGI2 and increased TXA2, thereby creating a condition favoring platelet aggregation and a variety of cardiovascular diseases.

Lubawy, W.C.; Valentovic, M.A.; Atkinson, J.E.; Gairola, G.C.

1983-08-08

358

The effects of xanthoangelol E on arachidonic acid metabolism in the gastric antral mucosa and platelet of the rabbit.  

PubMed

The effects of a new chalcone derivative, xanthoangelol E, isolated from Angelica keiskei Koidzumi, on arachidonic acid metabolism in the gastric antral mucosa and platelet of the rabbit were examined. When gastric antral mucosal slices were incubated with xanthoangelol E (0.05-1.0 mM), there was no significant effect on the production of prostaglandin (PG) E2, PGF2 alpha and their metabolites. On the other hand, this compound inhibited effectively the production of thromboxane B2 and 12-hydroxy-5,8,10-heptadecatrienoic acid from exogenous arachidonic acid in platelets, and the concentration required for 50% inhibition (IC50) was approximately 5 microM. The formation of 12-hydroxy-5,8,10,14-eicosatetraenoic acid was also reduced by this drug (IC50, 50 microM). These results suggest that xanthoangelol E has the potential to modulate arachidonic acid metabolism in platelets and that this action may participate in some pharmacological effect of the plant. PMID:1439191

Fujita, T; Sakuma, S; Sumiya, T; Nishida, H; Fujimoto, Y; Baba, K; Kozawa, M

1992-08-01

359

Omega-3 fatty acids increase the arachidonic acid content of liver cholesterol ester and plasma triacylglycerol fractions in the rat.  

PubMed Central

Recent studies have demonstrated that dietary fish oils rich in eicosapentaenoic acid (C20:5,omega 3) lower the content of arachidonic acid and its metabolites in plasma and tissue phospholipids. The present study examined the fatty acid composition of cholesterol ester and triacylglycerol fractions from plasma and livers of rats fed diets enriched with saturated fatty acids (beef tallow), alpha-linolenic acid (linseed oil) or eicosapentaenoic acid (fish oil). Feeding diets containing linseed oil or fish oil for 28 days increased arachidonic acid (C20:4,omega 6) levels in the cholesterol ester fraction of liver and in the triacylglycerol fraction of the plasma lipids. Plasma cholesterol esters were depleted of C20:4,omega 6 after feeding of the diet containing either linseed oil or fish oil. The changes in C20:4,omega 6 content cannot be explained by alterations in cholesterol ester or triacylglycerol pools of plasma and liver. These results suggest that the decrease in phospholipid C20:4,omega 6 content generally observed after fish oil consumption may be partly due to a shift of C20:4,omega 6 from phospholipid to the triacylglycerol and/or cholesterol ester pools in the same tissue. Triacylglycerols and cholesterol esters may therefore play a buffering role in the homeostatic maintenance of tissue phospholipid levels of arachidonic acid. Images Fig. 1. PMID:2775198

Garg, M L; Wierzbicki, A A; Thomson, A B; Clandinin, M T

1989-01-01

360

The biosynthesis of N-arachidonoyl dopamine (NADA), a putative endocannabinoid and endovanilloid, via conjugation of arachidonic acid with dopamine  

PubMed Central

Summary N-arachidonoyl dopamine (NADA) is an endogenous ligand that activates the cannabinoid type 1 receptor and the transient receptor potential vanilloid type 1 channel. Two potential biosynthetic pathways for NADA have been proposed, though no conclusive evidence exists for either. The first is the direct conjugation of arachidonic acid with dopamine; the other is via metabolism of a putative N-arachidonoyl tyrosine (NA-tyrosine). In the present study we investigated these biosynthetic mechanisms and report that NADA synthesis requires TH in dopaminergic terminals, however, NA-tyrosine, which we identify here as an endogenous lipid, is not an intermediate. We show that NADA biosynthesis primarily occurs through an enzyme-mediated conjugation of arachidonic acid with dopamine. While this conjugation likely involves a complex of enzymes, our data suggest a direct involvement of fatty acid amide hydrolase in NADA biosynthesis as either a rate-limiting enzyme that liberates arachidonic acid from AEA, as a conjugation enzyme, or both. PMID:19570666

Hu, Sherry Shu-Jung; Bradshaw, Heather B.; Benton, Valery M.; Chen, Jay Shih-Chieh; Huang, Susan M.; Minassi, Alberto; Bisogno, Tiziana; Masuda, Kim; Tan, Bo; Roskoski, Robert; Cravatt, Benjamin F.; Di Marzo, Vincenzo

2009-01-01

361

90-Day feeding and genotoxicity studies on a refined arachidonic acid-rich oil.  

PubMed

The safety of a refined arachidonic acid-rich oil (RAO) was evaluated for reverse mutation, chromosome aberration and gene mutation, and in a 90-day Wistar rat feeding study with in utero exposure. The results of the genotoxicity assays were all negative. The in utero phase of the 90-day study involved dietary exposure to 0.5%, 1.5% and 5% RAO and two controls diets, a standard feed low-fat diet and a high-fat diet supplemented with 5% corn oil. This exposure covered four-weeks prior to mating, through mating, gestation and lactation until offspring (F(1)) weaning. A subsequent 90-day feeding study in the F(1) rats evaluated the same test and control diets. Statistically significant effects were seen for selected histopathology, clinical chemistry and organ weight endpoints; however, other than increased absolute and relative monocytes seen in both sexes of high-dose rats, the observations were not attributed to treatment for one or more reasons. Based on these findings, no adverse treatment-related effects for RAO were seen at up to 5% in the diet, equivalent to an overall average RAO intake of 3170 mg/kg bwt/day. These and similar findings for other refined ARA-rich oils establish a strong body of evidence for the safety of this RAO. PMID:19576260

Casterton, P L; Curry, L L; Lina, B A R; Wolterbeek, A P M; Kruger, C L

2009-10-01

362

Pharmacological manipulation of arachidonic acid-epoxygenase results in divergent effects on renal damage  

PubMed Central

Kidney damage is markedly accelerated by high-salt (HS) intake in stroke-prone spontaneously hypertensive rats (SHRSP). Epoxyeicosatrienoic acids (EETs) are epoxygenase products of arachidonic acid which possess vasodepressor, natriuretic, and anti-inflammatory activities. We examined whether up-regulation (clofibrate) or inhibition [N-methylsulfonyl-6-(2-propargyloxyphenyl)hexanamide (MS-PPOH)] of epoxygenase would alter systolic blood pressure (SBP) and/or renal pathology in SHRSP on HS intake (1% NaCl drinking solution). Three weeks of treatment with clofibrate induced renal cortical protein expression of CYP2C23 and increased urinary excretion of EETs compared with vehicle-treated SHRSP. SBP and urinary protein excretion (UPE) were significantly lowered with clofibrate treatment. Kidneys from vehicle-treated SHRSP, which were on HS intake for 3 weeks, demonstrated focal lesions of vascular fibrinoid degeneration, which were markedly attenuated with clofibrate treatment. In contrast, 2 weeks of treatment with the selective epoxygenase inhibitor, MS-PPOH, increased UPE without significantly altering neither urinary EET levels nor SBP. Kidneys from vehicle-treated SHRSP, which were on HS intake for 11 days, demonstrated occasional mild damage whereas kidneys from MS-PPOH-treated rats exhibited widespread malignant nephrosclerosis. These results suggest that pharmacological manipulation of epoxygenase results in divergent effects on renal damage and that interventions to increase EET levels may provide therapeutic strategies for treating salt-sensitive hypertension and renal damage. PMID:25177296

Li, Jing; Stier, Charles T.; Chander, Praveen N.; Manthati, Vijay L.; Falck, John R.; Carroll, Mairéad A.

2014-01-01

363

Regulation of arachidonic acid in esophageal adenocarcinoma cells and tumor-infiltrating lymphocytes  

PubMed Central

The generation and development of esophageal adenocarcinoma (EAC) are correlated with neuroimmunological factors. The aim of this study was to observe the effectiveness of the neurotransmitter arachidonic acid (AA) on two EAC cell lines, OE19 and SK-GT-4, as well as three isolated tumor-infiltrating lymphocytes (TIL1, 2 and 3). C-X-C chemokine receptor type 4 (CXCR-4) and tumor necrosis factor receptor 1 (TNFR1) expression, cell migration, necrosis, cytokine secretion and cytotoxicity of TILs were investigated. AA dose-dependently increased the migration of all cells. However, AA did not increase the percentage of cell death of the three TILs in the presence of a necrosis-inducing agent. AA dose-dependently increased the cytotoxicity of the three ??T cell-enriched TILs compared with the OE19 and SK-GT-4 cell lines. AA also dose-dependently increased the secretion of interferon-? (IFN-?) and TNF-? in TIL1 and 2. However, the cytokine secretion and cytotoxicity activity of TIL3 and ??T cell-enriched TIL3 were the lowest. Furthermore, the percentage of CD4+forkhead box p3 (Foxp3)+ regulatory T cells in TIL3 was the highest. The effect of AA on tumor cells and TILs is different. The degree of malignancy of the tumor and the ratio of regulatory T cells may be the main factors determining the function of AA. PMID:23833663

SONG, WEI; JIANG, RUI; ZHAO, CHUNMING

2013-01-01

364

Arachidonic acid and calcium signals in human breast tumor-derived endothelial cells: a proteomic study.  

PubMed

Intracellular calcium signals activated by growth factors in endothelial cells during angiogenesis regulate cytosolic and nuclear events involved in survival, proliferation and motility. Among the intracellular messengers released upon proangiogenic stimulation, arachidonic acid (AA) and its metabolites play a key role, and their effects are strictly related to calcium homeostasis. In human breast tumor-derived endothelial cells (B-TECs) AA stimulates proliferation and tubulogenesis in a calcium-dependent way. Here, to characterize the proteins whose expression is regulated by AA-induced calcium entry, we used a proteomic approach (two-dimensional gel electrophoresis and matrix-assisted laser desorption ionization mass spectrometry, 2-DE and MALDI-MS) and we compared the proteomes of B-TECs stimulated with AA in presence or in absence of calcium entry (with addition to the culture medium of the calcium chelator EGTA, which completely prevents calcium fluxes throughout the plasma membrane). We found that six proteins increased their levels of expression, all higher when AA-induced calcium entry was abolished. These proteins have been identified by mass spectrometry and database search, and their potential roles in AA-stimulated pathway and in angiogenesis are discussed. PMID:19769547

Antoniotti, Susanna; Fattori, Paolo; Tomatis, Cristiana; Pessione, Enrica; Munaron, Luca

2009-01-01

365

Phospholipid sources for adrenic acid mobilization in RAW 264.7 macrophages. Comparison with arachidonic acid.  

PubMed

Cells metabolize arachidonic acid (AA) to adrenic acid (AdA) via 2-carbon elongation reactions. Like AA, AdA can be converted into multiple oxygenated metabolites, with important roles in various physiological and pathophysiological processes. However, in contrast to AA, there is virtually no information on how the cells regulate the availability of free AdA for conversion into bioactive products. We have used a comparative lipidomic approach with both gas chromatography and liquid chromatography coupled to mass spectrometry to characterize changes in the levels of AA- and AdA-containing phospholipid species in RAW 264.7 macrophage-like cells. Incubation of the cells with AA results in an extensive conversion to AdA but both fatty acids do not compete with each other for esterification into phospholipids. AdA but not AA, shows preference for incorporation into phospholipids containing stearic acid at the sn-1 position. After stimulation of the cells with zymosan, both AA and AdA are released in large quantities, albeit AA is released to a greater extent. Finally, a variety of phosphatidylcholine and phosphatidylinositol molecular species contribute to AA; however, AdA is liberated exclusively from phosphatidylcholine species. Collectively, these results identify significant differences in the cellular utilization of AA and AdA by the macrophages, suggesting non-redundant biological actions for these two fatty acids. PMID:22824377

Guijas, Carlos; Astudillo, Alma M; Gil-de-Gómez, Luis; Rubio, Julio M; Balboa, María A; Balsinde, Jesús

2012-11-01

366

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

PubMed Central

Arachidonic acid (20:4?5,8,11,14, 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 (?5 desaturase) gene reciprocally altered the levels of dihomo-?-linolenic acid (20:3?8,11,14, 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

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

2012-01-01

367

Intestinal zinc transport: influence of streptozotocin-induced diabetes, insulin and arachidonic acid  

SciTech Connect

The influence of arachidonic acid (AA) on the zinc flux rates of jejunal segments, isolated from streptozotocin-induced diabetic rats injected with saline or with insulin, was investigated using an Ussing chamber technique. Although the zinc flux rates from mucose-to-serosa (J/sub ms/) of normal rats were inhibited by addition of 5 ..mu..M AA to the jejunal segment bathing medium, AA had no effect on the J/sub ms/ of diabetic rats either with or without insulin treatment. Induction of diabetes also significantly reduces J/sub ms/, but 3 day insulin treatment did not reverse this effect. Addition of AA to the serosal side did not significantly alter the zinc flux rate from serosa-to-mucosa (J/sub sm/) in either control, diabetic or diabetic rats treated with insulin. The net zinc absorption rate (J/sub net/) of jejunal segments was decreased in diabetic rats compared to controls, but normalization of blood glucose with 3 day insulin treatment did not increase J/sub net/. Addition of AA was associated with a tendency to increase zinc uptake capacity. This change reached statistical significance in insulin treated diabetic rats. Short-circuit current (I/sub sc/) for diabetic rats was increased compared to controls but addition of AA to the mucosal side bathing medium decreased I/sub sc/ in all groups. 32 references, 3 figures, 1 table.

Song, M.K.; Mooradian, A.D.

1988-01-01

368

Arachidonic Acid: An Evolutionarily Conserved Signaling Molecule Modulates Plant Stress Signaling Networks[C][W  

PubMed Central

Fatty acid structure affects cellular activities through changes in membrane lipid composition and the generation of a diversity of bioactive derivatives. Eicosapolyenoic acids are released into plants upon infection by oomycete pathogens, suggesting they may elicit plant defenses. We exploited transgenic Arabidopsis thaliana plants (designated EP) producing eicosadienoic, eicosatrienoic, and arachidonic acid (AA), aimed at mimicking pathogen release of these compounds. We also examined their effect on biotic stress resistance by challenging EP plants with fungal, oomycete, and bacterial pathogens and an insect pest. EP plants exhibited enhanced resistance to all biotic challenges, except they were more susceptible to bacteria than the wild type. Levels of jasmonic acid (JA) were elevated and levels of salicylic acid (SA) were reduced in EP plants. Altered expression of JA and SA pathway genes in EP plants shows that eicosapolyenoic acids effectively modulate stress-responsive transcriptional networks. Exogenous application of various fatty acids to wild-type and JA-deficient mutants confirmed AA as the signaling molecule. Moreover, AA treatment elicited heightened expression of general stress-responsive genes. Importantly, tomato (Solanum lycopersicum) leaves treated with AA exhibited reduced susceptibility to Botrytis cinerea infection, confirming AA signaling in other plants. These studies support the role of AA, an ancient metazoan signaling molecule, in eliciting plant stress and defense signaling networks. PMID:20935246

Savchenko, Tatyana; Walley, Justin W.; Chehab, E. Wassim; Xiao, Yanmei; Kaspi, Roy; Pye, Matthew F.; Mohamed, Maged E.; Lazarus, Colin M.; Bostock, Richard M.; Dehesh, Katayoon

2010-01-01

369

The effect of trinitrobenzene sulfonic acid (TNB) on colonocyte arachidonic acid metabolism.  

PubMed

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

Stratton, M D; Sexe, R; Peterson, B; Kaminski, D L; Li, A P; Longo, W E

1996-02-01

370

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

PubMed

Arachidonic acid (AA) is one of only two unsaturated fatty acids retained in the ovaries of crustaceans, and an inhibitor of HR97g, a nuclear receptor expressed in adult ovaries. We hypothesized that as a key fatty acid, AA may be associated with reproduction and potentially environmental sex determination in Daphnia. Reproduction assays with AA indicate that it alters female/male sex ratios by increasing female production. This reproductive effect only occurred during a restricted P. subcapitata diet. Next, we tested whether enriching a poorer algal diet (C. vulgaris) with AA enhances overall reproduction and sex ratios. AA enrichment of a C. vulgaris diet also enhances fecundity at 1.0 and 4.0 ?M by 30-40% in the presence and absence of pyriproxyfen. This indicates that AA is crucial in reproduction regardless of environmental sex determination. Furthermore, our data indicates that P. subcapitata may provide a threshold concentration of AA needed for reproduction. Diet switch experiments from P. subcapitata to C. vulgaris mitigate some but not all of AA's effects when compared to a C. vulgaris only diet, suggesting that some AA provided by P. subcapitata is retained. In summary, AA supplementation increases reproduction and represses pyriproxyfen-induced environmental sex determination in D. magna in restricted diets. A diet rich in AA may provide protection from some reproductive toxicants such as the juvenile hormone agonist, pyriproxyfen. This article is protected by copyright. All rights reserved. PMID:25393616

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

2014-11-13

371

Epoxygenase metabolites of arachidonic acid inhibit vasopressin response in toad bladder  

SciTech Connect

In addition to cyclooxygenase and lipoxygenase pathways, the kidney can also metabolize arachidonic acid by a NADPH-dependent cytochrome P-450 enzyme to epoxyeicosatrienoic acids (EETs); furthermore, 5,6-EET has been shown to alter electrolyte transport across isolated renal tubules. The authors examined the effects of three ({sup 14}C-labeled)-EETs (5,6-, 11,12-, and 14,15-EET) on osmotic water flow across toad urinary bladder. All three EETs reversibly inhibited vasopressin-stimulated osmotic water flow with 5,6- and 11,12-EET being the most potent. The effects appeared to be independent of prostaglandins EETs inhibited the water flow response to forskolin but not the response to adenosine 3{prime},5{prime}-cyclic monophosphate (cAMP) or 8-BrcAMP, consistent with an effect on cAMP generation. To determine whether these effects were due to the EETs or to products of their metabolism, they examined the effects of their vicinal diol hydrolysis products, the dihydroxyeicosatrienoic acids. Nonenzymatic conversion of labeled 5,6-EET to its vicinal diol occurred rapidly in the buffer, whereas 11,12-EET was hydrolyzed in a saturable manner only when incubated in the presence of bladder tissue. The dihydroxyeicosatrienoic acids formed inhibited water flow in a manner paralleling that of the EETs. The data support the hypothesis that EETs and their physiologically active dihydroxyeicosatrienoic acid metabolites inhibit vasopressin-stimulated water flow predominantly via inhibition of adenylate cyclase.

Schlondorff, D.; Petty, E.; Oates, J.A.; Jacoby, M.; Levine, S.D. (Albert Einstein College of Medicine, Bronx, NY (USA) Vanderbilt Univ., Nashville, TN (USA))

1987-09-01

372

Arachidonate 15-lipoxygenase is required for chronic myeloid leukemia stem cell survival  

PubMed Central

Cancer stem cells (CSCs) are responsible for the initiation and maintenance of some types of cancer, suggesting that inhibition of these cells may limit disease progression and relapse. Unfortunately, few CSC-specific genes have been identified. Here, we determined that the gene encoding arachidonate 15-lipoxygenase (Alox15/15-LO) is essential for the survival of leukemia stem cells (LSCs) in a murine model of BCR-ABL–induced chronic myeloid leukemia (CML). In the absence of Alox15, BCR-ABL was unable to induce CML in mice. Furthermore, Alox15 deletion impaired LSC function by affecting cell division and apoptosis, leading to an eventual depletion of LSCs. Moreover, chemical inhibition of 15-LO function impaired LSC function and attenuated CML in mice. The defective CML phenotype in Alox15-deficient animals was rescued by depleting the gene encoding P-selectin, which is upregulated in Alox15-deficient animals. Both deletion and overexpression of P-selectin affected the survival of LSCs. In human CML cell lines and CD34+ cells, knockdown of Alox15 or inhibition of 15-LO dramatically reduced survival. Loss of Alox15 altered expression of PTEN, PI3K/AKT, and the transcription factor ICSBP, which are known mediators of cancer pathogenesis. These results suggest that ALOX15 has potential as a therapeutic target for eradicating LSCs in CML. PMID:25105362

Chen, Yaoyu; Peng, Cong; Abraham, Sheela A.; Shan, Yi; Guo, Zhiru; Desouza, Ngoc; Cheloni, Giulia; Li, Dongguang; Holyoake, Tessa L.; Li, Shaoguang

2014-01-01

373

Inhibition of ligand binding to G protein-coupled receptors by arachidonic acid.  

PubMed

Arachidonic acid (AA), released in response to muscarinic acetylcholine receptor (mAChR) stimulation, previously has been reported to function as a reversible feedback inhibitor of the mAChR. To determine if the effects of AA on binding to the mAChR are subtype specific and whether AA inhibits ligand binding to other G protein-coupled receptors (GPCRs), the effects of AA on ligand binding to the mAChR subtypes (M1, M2, M3, M4, and M5) and to the micro-opioid receptor, beta2-adrenergic receptor (beta2-AR), 5-hydroxytryptamine receptor (5-HTR), and nicotinic receptors were examined. AA was found to inhibit ligand binding to all mAChR subtypes, to the beta2-AR, the 5-HTR, and to the micro-opioid receptor. However, AA does not inhibit ligand binding to the nicotinic receptor, even at high concentrations of AA. Thus, AA inhibits several types of GPCRs, with 50% inhibition occurring at 3-25 MuM, whereas the nicotinic receptor, a non-GPCR, remains unaffected. Further research is needed to determine the mechanism by which AA inhibits GPCR function. PMID:16186629

Bordayo, Elizabeth Z; Fawcett, John R; Lagalwar, Sarita; Svitak, Aleta L; Frey, William H

2005-01-01

374

Arachidonic acid-dependent gene regulation during preadipocyte differentiation controls adipocyte potential[S  

PubMed Central

Arachidonic acid (AA) is a major PUFA that has been implicated in the regulation of adipogenesis. We examined the effect of a short exposure to AA at different stages of 3T3-L1 adipocyte differentiation. AA caused the upregulation of fatty acid binding protein 4 (FABP4/aP2) following 24 h of differentiation. This was mediated by the prostaglandin F2? (PGF2?), as inhibition of cyclooxygenases or PGF2? receptor signaling counteracted the AA-mediated aP2 induction. In addition, calcium, protein kinase C, and ERK are all key elements of the pathway through which AA induces the expression of aP2. We also show that treatment with AA during the first 24 h of differentiation upregulates the expression of the transcription factor Fos-related antigen 1 (Fra-1) via the same pathway. Finally, treatment with AA for 24 h at the beginning of the adipocyte differentiation is sufficient to inhibit the late stages of adipogenesis through a Fra-1-dependent pathway, as Fra-1 knockdown rescued adipogenesis. Our data show that AA is able to program the differentiation potential of preadipocytes by regulating gene expression at the early stages of adipogenesis. PMID:25325755

Nikolopoulou, Evanthia; Papacleovoulou, Georgia; Jean-Alphonse, Frederic; Grimaldi, Giulia; Parker, Malcolm G.; Hanyaloglu, Aylin C.; Christian, Mark

2014-01-01

375

Endothelium-derived hyperpolarizing factor in coronary microcirculation: responses to arachidonic acid.  

PubMed

In coronary resistance vessels, endothelium-derived hyperpolarizing factor (EDHF) plays an important role in endothelium-dependent vasodilation. EDHF has been proposed to be formed through cytochrome P-450 monooxygenase metabolism of arachidonic acid (AA). Our hypothesis was that AA-induced coronary microvascular dilation is mediated in part through a cytochrome P-450 pathway. The canine coronary microcirculation was studied in vivo (beating heart preparation) and in vitro (isolated microvessels). Nitric oxide synthase (NOS) (N(omega)-nitro-L-arginine, 100 microM) and cyclooxygenase (indomethacin, 10 microM) or cytochrome P-450 (clotrimazole, 2 microM) inhibition did not alter AA-induced dilation. However, when a Ca(2+)-activated K(+) channel channel or cytochrome P-450 antagonist was used in combination with NOS and cyclooxygenase inhibitors, AA-induced dilation was attenuated. We also show a negative feedback by NO on NOS-cyclooxygenase-resistant AA-induced dilation. We conclude that AA-induced dilation is attenuated by cytochrome P-450 inhibitors, but only when combined with inhibitors of cyclooxygenase and NOS. Therefore, redundant pathways appear to mediate the AA response in the canine coronary microcirculation. PMID:11557543

Oltman, C L; Kane, N L; Fudge, J L; Weintraub, N L; Dellsperger, K C

2001-10-01

376

Genetic modification of alternative respiration in Nicotiana benthamiana affects basal and salicylic acid-induced resistance to potato virus X  

E-print Network

RESEARCH ARTICLE Open Access Genetic modification of alternative respiration in Nicotiana benthamiana affects basal and salicylic acid-induced resistance to potato virus X Wing-Sham Lee1†, Shih-Feng Fu1†, Jeanmarie Verchot-Lubicz2, John P Carr1... capacity for alternative respiration, 0.5 mM SA was adequate to induce resistance to TMV infection even though it did not induce resistance to TMV in non-transgenic N. benthamiana leaves (Figure 4B). This was also seen in three other transgenic lines...

Lee, Wing-Sham; Fu, Shih-Feng; Verchot-Lubicz, Jeanmarie; Carr, John P

2011-02-28

377

496. Phys. Lett A., 355, N4-5,(2006),247-249. A.G.Ramm, The shape of the ear The shape of the ear canal  

E-print Network

496. Phys. Lett A., 355, N4-5,(2006),247-249. A.G.Ramm, The shape of the ear canal 1 #12;The shape of the ear canal A.G. Ramm Mathematics Department, Kansas State University, Manhattan, KS 66506-2602, USA ramm@math.ksu.edu Abstract It is proved that the measurement of the acoustic pressure on the ear

378

Efficacy of ear-point stimulation on experimentally induced seizure.  

PubMed

This study was to observe the effects of ear-point stimulation on electrocorticogram of sensorimotor cortex and behaviors of rats with penicillin-induced seizure. The model of epilepsy was by injecting penicillin into the hippocampus. One hour later, the lower 1/2 auricular lobules containing ear-points Pizhixia, Shenmen_Zeng and Nao, etc. as humans, or great auricular nerve of seizure rats, were treated twice with electrical stimulation (parameters of stimulation were as follows: electrical current intensity 0.14 approximately 0.2 mA, frequency about 80Hz, 30 min on and 30 min off). The outcome showed that rats appeared epileptic-like electrocorticogram and convulsion behaviors 5 min after injected penicillin. When they were subsequently given the ear-point or great auricular nerve electrical stimulation separately, these epileptic-like electrocorticogram and seizure behaviors were definitely improved. These anti-seizure effects could be enhanced with hour extension of electrical stimulation. If the great auricular nerve of seizure rat was severed before electrical stimulating ear-points, the effects of anti-seizure disappeared. Otherwise, the seizure rats given sham ear-point electrical stimulation (the experimental conditions were same as that of ear-point stimulation other than electric current being no applied) did not show any improvement for epileptic-like electrocorticogram and seizure behaviors. Based on the results above, it was suggested that ear-point electrical stimulation could cause certainly efficacy of anti-seizure, which may be relative with the great auricular nerve. PMID:16231631

Shu, Jia; Liu, Rong-Yu; Huang, Xian-Fen

2005-01-01

379

Bacterial contamination of commercial ear cleaners following routine home use.  

PubMed

Ear cleaning solutions are designed for repeated use, which raises the possibility for bacterial contamination leading to recurrent or persistent infectious otitis. The purpose of this study was to investigate the prevalence of bacterial contamination of commercial ear cleaners following routine home use in dogs and to describe the characteristics that are associated with contamination. Used ear cleaner bottles and information regarding their use were obtained from canine owners visiting veterinary dermatologists. Both the bottle applicator tips and the solution contents were cultured for aerobic bacteria. Bacterial contamination was present on 10% of the bottle tips and in 2% of the solutions. Isolated bacteria included Staphylococcus pseudintermedius, Bacillus spp., coagulase-negative Staphylococcus spp., Micrococcus spp. and Burkholderia cepacia. The contamination rate was significantly higher on the applicator tips than in the solutions (P = 0.0076). The applicator tip contamination rate was significantly higher in expired samples (17%) than in-date samples (4%; P = 0.0277). The bottle sizes were significantly larger for the samples with contaminated applicator tips compared with noncontaminated tips (P = 0.0455). The contamination rate was significantly higher when Tris-EDTA was an ingredient. Cleanliness of the bottle, contact with the ear canal and infection status of the ear at time of culture had no bearing on the contamination rate. In summary, with routine home use of commercial ear cleaners, pathogenic bacterial contamination is of minor concern. This concern may increase when expired products or larger bottles of ear cleaner are used and when Tris-EDTA is an ingredient. PMID:21645141

Bartlett, Sarah J; Rosenkrantz, Wayne S; Sanchez, Susan

2011-12-01

380

Bovine Cartilage: A Near Perfect Training Tool for Carving Ear Cartilage Framework.  

PubMed

Objective :? To develop a training module for carving ear cartilage. Setting :? Designing the ear framework is one of the most challenging surgical steps during ear reconstruction in microtia and acquired deformities of the ear. Trainees do not get an opportunity to carve ear cartilage during their training period. Material :? Ox scapular cartilage was retrieved from a manual slaughterhouse. It was transported in a 4°C ice chamber. This was used as a training material for carving the ear framework. Each scapular cartilage was adequate for two to three ear frameworks. Results :? Twenty-two trainees used the bovine cartilage in a wet lab. All had positive feedback on their ear framework carving experience. In their opinion, the consistency, flexibility, and cutting experience almost matched that of human costal cartilage. Conclusion :? The ox scapular cartilage has been found to be a near perfect material for training and practicing carving of the ear cartilage. PMID:25372551

Agrawal, Karoon

2014-11-01

381

Molecular Conservation and Novelties in Vertebrate Ear Development  

PubMed Central

Evolution shaped the vertebrate ear into a complicated three-dimensional structure and positioned the sensory epithelia so that they can extract specific aspects of mechanical stimuli to govern vestibular and hearing-related responses of the whole organism. This information is conducted from the ear via specific neuronal connections to distinct areas of the hindbrain for proper processing. During development, the otic placode, a simple sheet of epidermal cells, transforms into a complicated system of ducts and recesses. This placode also generates the mechanoelectrical transducers, the hair cells, and sensory neurons of the vestibular and cochlear (spiral) ganglia of the ear. We argue that ear development can be broken down into dynamic processes that use a number of known and unknown genes to govern the formation of the three-dimensional labyrinth in an interactive fashion. Embedded in this process, but in large part independent of it, is an evolutionary conserved process that induces early the development of the neurosensory component of the ear. We present molecular data suggesting that this later process is, in its basic aspects, related to the mechanosensory cell formation across phyla and is extremely conserved at the molecular level. We suggest that sensory neuron development and maintenance are vertebrate or possibly chordate novelties and present the molecular data to support this notion. PMID:14674476

Fritzsch, B.; Beisel, K. W.

2014-01-01

382

Manganese Accumulation in the Mouse Ear Following Systemic Exposure  

PubMed Central

There is evidence in human populations that exposure to manganese (Mn), or Mn in combination with excessive noise exposure, results in hearing loss. Quantitative reverse-transcriptase polymerase chain reaction revealed expression of the metal transporters DMT1, ZIP8, and ZIP14 in control mouse ears. ZIP8 is known to have a high affinity (Km = 2.2 ?M) for Mn transport, and ZIP8 protein was localized to the blood vessels of the ear by immunohistochemistry. We treated mice (strains C57BL/6J and DBA/2J) with Mn (100 mg/kg MnCl2, by subcutaneous injection, on three alternating days), and Mn was significantly elevated in the ears of the treated mice. Mn concentrations remained elevated over controls for at least 2 weeks after treatment. These studies demonstrate that metal transporters are present in the mouse ear and that Mn can accumulate in the ear following systemic exposure. Future studies should focus on whether Mn exposure is associated with hearing deficits. PMID:18972394

Ma, Ci; Schneider, Scott N.; Miller, Marian; Nebert, Daniel W.; Lind, Caroline; Roda, Sandy M.; Afton, Scott E.; Caruso, Joseph A.; Genter, Mary Beth

2009-01-01

383

Xuebijing injection improves the respiratory function in rabbits with oleic acid-induced acute lung injury by inhibiting IL-6 expression and promoting IL-10 expression at the protein and mRNA levels  

PubMed Central

Xuebijing injection is a complex herbal medicine, and clinical and experimental studies have shown that it has a significant effect on acute respiratory distress syndrome and multiple organ dysfunction syndrome. However, the majority of studies regarding Xuebijing injection have focused on serum inflammatory factors, and few studies have been carried out from the perspective of the protein and mRNA expression of inflammatory cytokines. In this study, 60 healthy rabbits of mixed gender were randomly assigned to a normal control group (CG), oleic acid group (model group; MG) and oleic acid + Xuebijing injection group (treatment group; TG). Rabbits of the CG were treated with normal saline through the ear vein, rabbits of the MG were injected with oleic acid (0.4 ml/kg) and rabbits of the TG received 0.4 ml/kg oleic acid + 10 ml/kg Xuebijing injection. Blood samples were collected from the common carotid artery of all rabbits of all groups 1 h after the ear vein was injected with the corresponding reagent, and was used to measure the arterial partial pressure of oxygen (PaO2) and of carbon dioxide (PaCO2). The activity of myeloperoxidase (MPO) was tested, and the protein and mRNA expression levels of interleukin (IL)-6 and IL-10 were determined. Rabbits of the MG exhibited evident respiratory dysfunction (PaO2 and PaCO2 were low), histopathological lung damage and overactive inflammatory responses (the expression of the proinflammatory cytokine IL-6 and the anti-inflammatory cytokine IL-10 was increased at the protein and mRNA levels). Following the administration of the Xuebijing injection, the inflammatory response of the rabbits was significantly reduced. Xuebijing injection raised PaO2 and PaCO2, weakened the activity of MPO in the lung tissue, downregulated the expression of the proinflammatory cytokine IL-6 and further increased the expression of the anti-inflammatory cytokine IL-10. These results demonstrated that Xuebijing injection improved the respiratory function of rabbits with acute oleic acid-induced lung injury by inhibiting IL-6 expression and promoting IL-10 expression. PMID:25289065

WANG, YUXIA; JI, MINGLI; WANG, LEI; CHEN, LIPING; LI, JING

2014-01-01

384

Protective effect of comaruman, a pectin of cinquefoil Comarum palustre L., on acetic acid-induced colitis in mice.  

PubMed

The efficacy of comaruman CP, a pectin of marsh cinquefoil Comarum palustre L., was investigated using a model of acetic acid-induced colitis in mice. Mice were administered comaruman CP orally 2 days prior to rectal injection of 5% acetic acid and examined for colonic damage 24 hr later. Colonic inflammation was characterized by macroscopical injury, higher levels of myeloperoxidase activity, enhanced vascular permeability, and diminution of colonic mucus. Oral administration of comaruman CP was found to prevent progression of colitis. Colonic macroscopic scores and the total square of damage were significantly reduced in mice treated with CP compared with the vehicle-treated colitis group. Peroral pretreatment of mice with comaruman CP was shown to decrease tissue myeloperoxidase activity in colons compared with the colitis group. Comaruman CP was found to stimulate production of mucus by colons of normal and colitis mice. Comaruman CP decreased the inflammatory status of normal mice as elicited by reduction of vascular permeability and adhesion of peritoneal neutrophils and macrophages. Thus, a preventive effect of comaruman on acetic acid-induced colitis in mice was detected. Reduction of neutrophil infiltration and enhancement of colon-bound mucus may be implicated in the protective effect of comaruman. PMID:16927150

Popov, Sergey V; Ovodova, Raisa G; Markov, Pavel A; Nikitina, Ida R; Ovodov, Yury S

2006-09-01

385

Effects of tumour necrosis factor-alpha synthesis inhibitors on rat trinitrobenzene sulphonic acid-induced chronic colitis.  

PubMed

The fact that tumour necrosis factor-alpha (TNF-alpha) is clearly involved in the pathogenesis of intestinal bowel disease, especially Crohn's disease, suggests that TNF-alpha synthesis inhibitors could be beneficial for treatment. The present study assessed the effect of chronic oral gavage of two in vitro TNF-alpha synthesis inhibitors, JM 34 maleate or [N-(4,6-dimethylpyridin-2-yl)-furane-2-carboxamide)] maleate and XC 21 or (N-betapicolyl-tetrafluorophtalimide), on colonic inflammation in trinitrobenzene sulphonic acid-induced colitis in rats. Rats received JM 34 maleate (100 mg/kg) and XC 21 (50 mg/kg) 1 h before colitis induction and then daily for 8 days by oral gavage. The colon was removed on day 8 and processed for clinical score, myeloperoxidase activity, and soluble TNF-alpha release. Treatment with XC 21, as well as dexamethasone and sulphasalazine, reduced colonic damage and decreased (except with dexamethasone) the incidence of diarrhoea. JM 34 maleate failed to improve the clinical signs of chronic colitis. After trinitrobenzene sulphonic acid-induced colitis, myeloperoxidase activity and TNF-alpha colonic mucosal production were substantially increased compared to the control (saline instillation). Both of these inflammatory indicators were then significantly decreased (P< or =0.05) after the four chronic treatments (JM 34 maleate, XC 21, sulphasalazine, and dexamethasone). XC 21 appeared to be as efficient as sulphasalazine in improving colonic inflammation. PMID:11716848

Bobin-Dubigeon, C; Collin, X; Grimaud, N; Robert, J M; Le Baut, G; Petit, J Y

2001-11-01

386

Anomalous Brownian motion discloses viscoelasticity in the ear’s mechanoelectrical-transduction apparatus  

PubMed Central

The ear detects sounds so faint that they produce only atomic-scale displacements in the mechanoelectrical transducer, yet thermal noise causes fluctuations larger by an order of magnitude. Explaining how hearing can operate when the magnitude of the noise greatly exceeds that of the signal requires an understanding both of the transducer’s micromechanics and of the associated noise. Using microrheology, we characterize the statistics of this noise; exploiting the fluctuation-dissipation theorem, we determine the associated micromechanics. The statistics reveal unusual Brownian motion in which the mean square displacement increases as a fractional power of time, indicating that the mechanisms governing energy dissipation are related to those of energy storage. This anomalous scaling contradicts the canonical model of mechanoelectrical transduction, but the results can be explained if the micromechanics incorporates viscoelasticity, a salient characteristic of biopolymers. We amend the canonical model and demonstrate several consequences of viscoelasticity for sensory coding. PMID:22328158

Kozlov, Andrei S.; Andor-Ardó, Daniel; Hudspeth, A. J.

2012-01-01

387

Conserved valproic-acid-induced lipid droplet formation in Dictyostelium and human hepatocytes identifies structurally active compounds  

PubMed Central

SUMMARY Lipid droplet formation and subsequent steatosis (the abnormal retention of lipids within a cell) has been reported to contribute to hepatotoxicity and is an adverse effect of many pharmacological agents including the antiepileptic drug valproic acid (VPA). In this study, we have developed a simple model system (Dictyostelium discoideum) to investigate the effects of VPA and related compounds in lipid droplet formation. In mammalian hepatocytes, VPA increases lipid droplet accumulation over a 24-hour period, giving rise to liver cell damage, and we show a similar effect in Dictyostelium following 30 minutes of VPA treatment. Using 3H-labelled polyunsaturated (arachidonic) or saturated (palmitic) fatty acids, we shown that VPA treatment of Dictyostelium gives rise to an increased accumulation of both types of fatty acids in phosphatidylcholine, phosphatidylethanolamine and non-polar lipids in this time period, with a similar trend observed in human hepatocytes (Huh7 cells) labelled with [3H]arachidonic acid. In addition, pharmacological inhibition of ?-oxidation in Dictyostelium phenocopies fatty acid accumulation, in agreement with data reported in mammalian systems. Using Dictyostelium, we then screened a range of VPA-related compounds to identify those with high and low lipid-accumulation potential, and validated these activities for effects on lipid droplet formation by using human hepatocytes. Structure-activity relationships for these VPA-related compounds suggest that lipid accumulation is independent of VPA-catalysed teratogenicity and inositol depletion. These results suggest that Dictyostelium could provide both a novel model system for the analysis of lipid droplet formation in human hepatocytes and a rapid method for identifying VPA-related compounds that show liver toxicology. PMID:22003123

Elphick, Lucy M.; Pawolleck, Nadine; Guschina, Irina A.; Chaieb, Leila; Eikel, Daniel; Nau, Heinz; Harwood, John L.; Plant, Nick J.; Williams, Robin S. B.

2012-01-01

388

The 5-lipoxygenase inhibitor, zileuton, suppresses prostaglandin biosynthesis by inhibition of arachidonic acid release in macrophages  

PubMed Central

BACKGROUND AND PURPOSE Zileuton is the only 5-lipoxygenase (5-LOX) inhibitor marketed as a treatment for asthma, and is often utilized as a selective tool to evaluate the role of 5-LOX and leukotrienes. The aim of this study was to investigate the effect of zileuton on prostaglandin (PG) production in vitro and in vivo. EXPERIMENTAL APPROACH Peritoneal macrophages activated with lipopolysaccharide (LPS)/interferon ? (LPS/IFN?), J774 macrophages and human whole blood stimulated with LPS were used as in vitro models and rat carrageenan-induced pleurisy as an in vivo model. KEY RESULTS Zileuton suppressed PG biosynthesis by interference with arachidonic acid (AA) release in macrophages. We found that zileuton significantly reduced PGE2 and 6-keto prostaglandin F1? (PGF1?) levels in activated mouse peritoneal macrophages and in J774 macrophages. This effect was not related to 5-LOX inhibition, because it was also observed in macrophages from 5-LOX knockout mice. Notably, zileuton inhibited PGE2 production in LPS-stimulated human whole blood and suppressed PGE2 and 6-keto PGF1? pleural levels in rat carrageenan-induced pleurisy. Interestingly, zileuton failed to inhibit the activity of microsomal PGE2 synthase1 and of cyclooxygenase (COX)-2 and did not affect COX-2 expression. However, zileuton significantly decreased AA release in macrophages accompanied by inhibition of phospholipase A2 translocation to cellular membranes. CONCLUSIONS AND IMPLICATION Zileuton inhibited PG production by interfering at the level of AA release. Its mechanism of action, as well as its use as a pharmacological tool, in experimental models of inflammation should be reassessed. PMID:20880396

Rossi, A; Pergola, C; Koeberle, A; Hoffmann, M; Dehm, F; Bramanti, P; Cuzzocrea, S; Werz, O; Sautebin, L

2010-01-01

389

Arachidonic and docosahexaenoic acids are biosynthesized from their 18-carbon precursors in human infants.  

PubMed Central

It is becoming clear that an adequate level of long-chain highly unsaturated fatty acids in the nervous system is required for optimal function and development; however, the ability of infants to biosynthesize long-chain fatty acids is unknown. This study explores the capacity of human infants to convert 18-carbon essential fatty acids to their elongated and desaturated forms, in vivo. A newly developed gas chromatography/negative chemical ionization/mass spectrometry method employing 2H-labeled essential fatty acids allowed assessment of this in vivo conversion with very high sensitivity and selectivity. Our results demonstrate that human infants have the capacity to convert dietary essential fatty acids administered enterally as 2H-labeled ethyl esters to their longer-chain derivatives, transport them to plasma, and incorporate them into membrane lipids. The in vivo conversion of linoleic acid (18:2n6) to arachidonic acid (20:4n6) is demonstrated in human beings. All elongases/desaturases necessary for the conversion of linolenic acid (18:3n3) to docosahexaenoic acid (22:6n3) are also active in the first week after birth. Although the absolute amounts of n-3 fatty acid metabolites accumulated in plasma are greater than those of the n-6 family, estimates of the endogenous pools of 18:2n6 and 18:3n3 indicate that n-6 fatty acid conversion rates are greater than those of the n-3 family. While these data clearly demonstrate the capability of infants to biosynthesize 22:6n3, a lipid that is required for optimal neural development, the amounts produced in vivo from 18:3n3 may be inadequate to support the 22:6n3 level observed in breast-fed infants. PMID:8552667

Salem, N; Wegher, B; Mena, P; Uauy, R

1996-01-01

390

Lovastatin increases arachidonic acid levels and stimulates thromboxane synthesis in human liver and monocytic cell lines.  

PubMed Central

The effect of lovastatin (LOV), the inhibitor of 3-hydroxy-3-methyl-glutaryl coenzyme A reductase, on linoleic acid (LA, 18:2n-6) metabolism was examined in human monocytic Mono Mac 6 (MM6) and hepatoma Hep G2 cells. The desaturation of LA was examined after LOV (72 h, 10 microM) or dimethylsulfoxide (LOV carrier, < 0.1%) and [14C]LA (last 18 h, 0.3 microCi, 5 microM). In both cell lines, LOV reduced the percentage of 14C label associated with LA and increased the percentage of label in the 20:4n-6 and the 22:5n-6 fractions. In Hep G2 but not MM6 cells, this effect was fully reversible by means of coincubation with mevalonic acid (500 microM), but not with cholesterol or lipoproteins. In both cell lines, the LOV-mediated increase in LA desaturation resulted in dose-dependent reductions of LA and elevations of AA in cellular phospholipids. The lipids secreted by LOV-treated Hep G2 cells were also enriched in arachidonic acid (AA). In the MM6 cells, LOV increased release of thromboxane upon stimulation with the calcium ionophore A23187. In summary, our findings of higher LA desaturation and AA enrichment of lipids secreted by the Hep G2 cells suggest that LOV treatment may increase the delivery of AA from the liver to extrahepatic tissues. The changes in membrane fatty acid composition can influence a variety of cellular functions, such as eicosanoid synthesis in monocytic cells. The mechanism appears to be related to the reduced availability of intermediates of cholesterogenesis. PMID:8282787

Hrboticky, N; Tang, L; Zimmer, B; Lux, I; Weber, P C

1994-01-01

391

Critical role of arachidonic acid-activated mTOR signaling in breast carcinogenesis and angiogenesis.  

PubMed

The mammalian target of rapamycin (mTOR) signaling pathway is upregulated in the pathogenesis of many cancers. Arachidonic acid (AA) and its metabolites play critical role in the development of breast cancer, but the mechanisms through which AA promotes mammary tumorigenesis and progression are poorly understood. We found that the levels of AA and cytosolic phospholipase A2 (cPLA2) strongly correlated with the signaling activity of mTORC1 and mTORC2 as well as the expression levels of vascular epithelial growth factor (VEGF) in human breast tumor tissues. In cultured breast cancer cells, AA effectively activated both mTOR complex 1 (mTORC1) and mTORC2. Interestingly, AA-stimulated mTORC1 activation was independent of amino acids, phosphatidylinositol 3-kinase (PI3-K) and tuberous sclerosis complex 2 (TSC2), which suggests a novel mechanism for mTORC1 activation. Further studies revealed that AA stimulated mTORC1 activity through destabilization of mTOR-raptor association in ras homolog enriched in brain (Rheb)-dependent mechanism. Moreover, we showed that AA-stimulated cell proliferation and angiogenesis required mTOR activity and that the effect of AA was mediated by lipoxygenase (LOX) but not cyclooxygenase-2 (COX-2). In animal models, AA-enhanced incidences of rat mammary tumorigenesis, tumor weights and angiogenesis were inhibited by rapamycin. Our findings suggest that AA is an effective intracellular stimulus of mTOR and that AA-activated mTOR plays critical roles in angiogenesis and tumorigenesis of breast cancer. PMID:22349822

Wen, Z-H; Su, Y-C; Lai, P-L; Zhang, Y; Xu, Y-F; Zhao, A; Yao, G-Y; Jia, C-H; Lin, J; Xu, S; Wang, L; Wang, X-K; Liu, A-L; Jiang, Y; Dai, Y-F; Bai, X-C

2013-01-10

392

Arachidonic acid cascade and the generation of ischemia- and reperfusion-induced ventricular arrhythmias.  

PubMed

This article reviews the evidence we found in our study that the local generation of thromboxane and prostacyclin is one important factor involved in determining the severity of the ventricular arrhythmias that result from acute myocardial ischaemia and subsequent reperfusion. The hypothesis examined is that thromboxane release, presumably from platelets, is harmful in the early stages of ischaemia (perhaps because this induces further platelet aggregation and/or a reduction in blood flow as a result of both active vasoconstriction and of mechanical obstruction) and that prostacyclin generation (presumably mainly from endothelial cells) is beneficial at this time. The evidence is that in anaesthetised greyhound dogs, blockade of the thromboxane receptor (AH 23848) or inhibition of thromboxane synthesis (with a variety of "specific" inhibitors of thromboxane synthetase such as dazoxiben, dazmegrel, and "low-dose" aspirin) slightly reduces the severity of ischaemia-induced arrhythmias and markedly increases survival after myocardial reperfusion by reducing reperfusion-induced ventricular fibrillation (e.g., from 80% in control dogs to less than 20% in treated dogs). The evidence that prostacyclin generation is helpful in this situation comes from studies with locally infused prostacyclin or iloprost and with nafazatrom, a drug that increases the amount of prostacyclin released into local coronary venous blood soon after the onset of myocardial ischaemia; these procedures also reduce the number of ventricular extrasystoles occurring during ischaemia and the incidence of reperfusion-induced ventricular fibrillation. These findings do not imply that arachidonic acid derivatives are the only, or even the main, biochemical factor involved in the generation of these arrhythmias.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:2410739

Parratt, J R; Coker, S J

1985-01-01

393

Modulation of leukotriene release from human polymorphonuclear leucocytes by PMA and arachidonic acid.  

PubMed Central

Stimulation of human neutrophils (PMN) with Ca ionophore A23187, opsonized zymosan and formyl-L-methionyl-L-leucyl-phenylalanine (FMLP) led to a time- and dose-dependent release of LTB4, 20-OH-LTB4, 20-COOH-LTB4, 6-trans-LTB4, 12-epi-6-trans LTB4 and LTC4, as detected by reverse-phase HPLC. Preincubation of the PMN suspension in the presence of Ca2+ and Mg2+ with phorbol-12-myristate-13-acetate (PMA) did not release leukotrienes by itself, but modulated the subsequent Ca ionophore-induced leukotriene release. The release of LTC4, 20-OH-LTB4 and 20-COOH-LTB4 was significantly decreased. Lesser effects were observed for the release of LTB4 and the non-enzymatic LTB4 isomers. In contrast, opsonized zymosan and FMLP enhanced the release of LTB4 and LTB4-omega-oxidation products from cells pretreated with PMA. With arachidonic acid as prestimulus, the amounts of the LTB4 isomers (6-trans-LTB4 and 12-epi-6-trans-LTB4) were enhanced significantly on subsequent stimulation with Ca ionophore. Prestimulation of lymphocytes, monocytes and basophilic granulocytes (LMB) with PMA had no significant effects on the ionophore-induced release of LTC4 and LTB4. PMN, but not LMB, suspensions prestimulated with PMA convert exogenously added LTC4 to LTB4 isomers and LTC4 sulphoxide. Our data suggest that preincubation of human granulocytes with PMA modified leukotriene release by activation or inhibition of different metabolic pathways for LTC4 and LTB4. PMID:2838420

Raulf, M; König, W

1988-01-01

394

Petroselinic acid from dietary triacylglycerols reduces the concentration of arachidonic acid in tissue lipids of rats.  

PubMed

Studies in vitro have revealed that triacylglycerols containing petroselinoyl [18:1(n-12)] moieties are hydrolyzed by pancreatic lipase at much lower rates than other triacylglycerols. To assess the lipolysis and absorption in vivo of such unusual triacylglycerols, diets containing 120 g seed oil triacylglycerols of coriander (Coriandrum sativum) per kg diet at a level of 72 g 18:1(n-12) moieties/100 g oil were fed to a group of weaned male Wistar rats without restriction for a period of 10 wk. For comparison, groups of rats were fed similar isocaloric diets containing plant oil triacylglycerols with various levels of oleoyl [18:1(n-9)] moieties, e.g., high oleic sunflower seed oil [75 g 18:1(n-9)/100 g oil], olive oil [(66 g 18:1(n-9)/100 g oil], medium oleic rapeseed oil [54 g 18:1(n-9)/100 g oil] and conventional high linoleic sunflower seed oil [25 g 18:1(n-9)/100 g oil]. All diets were supplemented with 20 g corn oil/kg diet. Consumption of coriander oil, compared with the other oils, led to significantly greater liver weights. No significant differences were observed among the groups fed various levels of oleic acid in body weight, the weights of heart, liver, kidneys, spleen or testes, lipid content of heart, or total cholesterol, HDL cholesterol and triacylglycerol concentrations of blood plasma. Ingestion of coriander oil led to incorporation of 18:1(n-12) into heart, liver and blood lipids and to a significant reduction in the concentration of arachidonic acid in the lipids of heart, liver and blood with a concomitant increase in the concentration of linoleic acid compared with results for the other groups.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7782911

Weber, N; Richter, K D; Schulte, E; Mukherjee, K D

1995-06-01

395

Comparison of arachidonate metabolism by alveolar macrophages from bighorn and domestic sheep.  

PubMed

We have defined the metabolites of arachidonic acid (AA) secreted by alveolar macrophages (AMs) of bighorn sheep and domestic sheep in response to three agents: calcium ionophore A23187, phorbol myristate acetate (PMA), and opsonized zymosan. Cells were labeled with [3H]AA prior to stimulation and 11 tritiated metabolites, including prostaglandins (PGs), thromboxanes (TXs), leukotrienes (LTs), and hydroxyeicosatetraenoic acids (HETEs), were detected and quantitated by high-performance liquid chromotography and radiometry. Zymosan stimulation resulted in the release of significantly elevated quantities (P less than 0.05), of LTB4, [5(S), 12(R)-dihydroxy-6,14-cis-8,10-trans-eicosatetraenoic acid], 5-HETE, [5(S)-hydroxyeicosatetraenoic acid], and the nonenzymatic isomers of LTB4, [LTB I, 5(S),12(R)-6-trans-LTB4] and LTB II, [5(S), 12(S)-6-trans-LTB4], from domestic sheep AM when compared to bighorn sheep AM. Phorbol myristate acetate (PMA) stimulation released significantly elevated quantities (P less than 0.04), of TXB2, (thromboxane B2), HHT, [12(S)-12-hydroxy-5,8,10-heptadecaenoic acid], LTB I, LTB II, and 15-HETE, [15(S)-hydroxyeicosatetraenoic acid] from domestic sheep AMs when compared to bighorn sheep AMs. However, after A23187 challenge, only 15-HETE was significantly elevated (P less than 0.04) in domestic sheep AMs when compared to bighorn sheep AMs. These clear differences in AA metabolism of AMs obtained from bighorn and domestic sheep in response to three different agonists suggest not only different control mechanisms for lung metabolism of AA in the two species, but also suggest that differences in the metabolites released may lead to quite different regulation of lung defense mechanisms in the two sheep species. PMID:1905271

Silflow, R M; Foreyt, W J; Taylor, S M; Laegreid, W W; Liggitt, H D; Leid, R W

1991-02-01

396

Imaging Neuroinflammation in Alzheimer Disease with Radiolabeled Arachidonic Acid and PET  

PubMed Central

Rationale Incorporation coefficients K* of arachidonic acid (AA) in brain are increased in a rat model of neuroinflammation, as are other markers of AA metabolism. Data also indicate that neuroinflammation contributes to Alzheimer disease (AD). On the basis of these observations, K* for AA was hypothesized to be elevated in AD patients. Methods Eight AD patients were studied with an average Mini-Mental State Examination (MMSE) score of 14.7 ± 8.4 (S.D.), aged 71.7 ± 11.2 years, as were 9 controls with a normal MMSE score, aged 68.7 ± 5.6 years. Each subject received a [15O]water positron emission tomography (PET) scan of regional cerebral blood flow (rCBF), followed after 15 min by a [1-11C]AA scan of regional K* for AA. Results In the AD compared to control subjects, global grey-matter K* for AA (corrected or uncorrected for the partial volume error, PVE) was significantly elevated, whereas only PVE-uncorrected global CBF was reduced significantly (p < 0.05). A False Discovery Rate (FDR) procedure indicated that PVE-corrected K* for AA was increased in 78 of 90 identified hemispheric grey-matter regions. PVE-corrected rCBF, although decreased in 12 regions at p < 0.01 by unpaired t-tests, did not survive the FDR procedure. The surviving K* increments were widespread in the neocortex, but were absent in caudate, pallidum and thalamic regions. Conclusions These preliminary results show that K* for AA is widely elevated in the AD brain, particularly in regions reported to have high densities of senile (neuritic) plaques with activated microglia. To the extent that the elevations represent upregulated AA metabolism associated with neuroinflammation, PET with [1-11C]AA could be used to examine neuroinflammation in patients with AD and other brain diseases. PMID:18703605

Esposito, Giuseppe; Giovacchini, Giampiero; Liow, Jeih-San; Bhattacharjee, Abesh K.; Greenstein, Dede; Schapiro, Mark; Hallett, Mark; Herscovitch, Peter; Eckelman, William C.; Carson, Richard E.; Rapoport, Stanley I.

2008-01-01

397

Contrasting effects of arachidonic acid and docosahexaenoic acid membrane incorporation into cardiomyocytes on free cholesterol turnover.  

PubMed

The preservation of a constant pool of free cholesterol (FC) is critical to ensure several functions of cardiomyocytes. We investigated the impact of the membrane incorporation of arachidonic acid (C20:4 ?6, AA) or docosahexaenoic acid (C22:6 ?3, DHA) as ?6 or ?3 polyunsaturated fatty acids (PUFAs) on cholesterol homeostasis in primary cultures of neonatal rat cardiac myocytes. We measured significant alterations to the phospholipid FA profiles, which had markedly different ?6/?3 ratios between the AA and DHA cells (13 vs. 1). The AA cells showed a 2.7-fold lower cholesterol biosynthesis than the DHA cells. Overall, the AA cells showed 2-fold lower FC masses and 2-fold higher cholesteryl ester masses than the DHA cells. The AA cells had a lower FC to phospholipid ratio and higher triglyceride levels than the DHA cells. Moreover, the AA cells showed a 40% decrease in ATP binding cassette transporter A1 (ABCA1)-mediated and a 19% decrease in ABCG1-mediated cholesterol efflux than the DHA cells. The differences in cholesterol efflux pathways induced by AA or DHA incorporation were not caused by variations in ABCs transporter expression and were reduced when ABC transporters were overexpressed by exposure to LXR/RXR agonists. These results show that AA incorporation into cardiomyocyte membranes decreased the FC turnover by markedly decreasing the endogenous cholesterol synthesis and by decreasing the ABCA1- and ABCG1-cholesterol efflux pathways, whereas DHA had the opposite effects. We propose that these observations may partially contribute to the beneficial effects on the heart of a diet containing a high ?3/?6 PUFA ratio. PMID:25019598

Doublet, Aline; Robert, Véronique; Vedie, Benoît; Rousseau-Ralliard, Delphine; Reboulleau, Anne; Grynberg, Alain; Paul, Jean-Louis; Fournier, Natalie

2014-10-01

398

Enhancement of arachidonic acid signaling pathway by nicotinic acid receptor HM74A  

SciTech Connect

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.

Tang, Yuting [Endocrine Therapeutics and Metabolic Disorders, Johnson and Johnson Pharmaceutical Research and Development, L.L.C., 1000 Rt. 202, Raritan, NJ 08869 (United States)]. E-mail: ytang@prdus.jnj.com; Zhou, Lubing [Endocrine Therapeutics and Metabolic Disorders, Johnson and Johnson Pharmaceutical Research and Development, L.L.C., 1000 Rt. 202, Raritan, NJ 08869 (United States); Gunnet, Joseph W. [Endocrine Therapeutics and Metabolic Disorders, Johnson and Johnson Pharmaceutical Research and Development, L.L.C., 1000 Rt. 202, Raritan, NJ 08869 (United States); Wines, Pamela G. [Endocrine Therapeutics and Metabolic Disorders, Johnson and Johnson Pharmaceutical Research and Development, L.L.C., 1000 Rt. 202, Raritan, NJ 08869 (United States); Cryan, Ellen V. [Endocrine Therapeutics and Metabolic Disorders, Johnson and Johnson Pharmaceutical Research and Development, L.L.C., 1000 Rt. 202, Raritan, NJ 08869 (United States); Demarest, Keith T. [Endocrine Therapeutics and Metabolic Disorders, Johnson and Johnson Pharmaceutical Research and Development, L.L.C., 1000 Rt. 202, Raritan, NJ 08869 (United States)

2006-06-23

399

Reduced macrophage selenoprotein expression alters oxidized lipid metabolite biosynthesis from arachidonic and linoleic acid.  

PubMed

Uncontrolled inflammation is an underlying etiology for multiple diseases and macrophages orchestrate inflammation largely through the production of oxidized fatty acids known as oxylipids. Previous studies showed that selenium (Se) status altered the expression of oxylipids and magnitude of inflammatory responses. Although selenoproteins are thought to mediate many of the biological effects of Se, the direct effect of selenoproteins on the production of oxylipids is unknown. Therefore, the role of decreased selenoprotein activity in modulating the production of biologically active oxylipids from macrophages was investigated. Thioglycollate-elicited peritoneal macrophages were collected from wild-type and myeloid-cell-specific selenoprotein knockout mice to analyze oxylipid production by liquid chromatography/mass spectrometry as well as oxylipid biosynthetic enzyme and inflammatory marker gene expression by quantitative real-time polymerase chain reaction. Decreased selenoprotein activity resulted in the accumulation of reactive oxygen species, enhanced cyclooxygenase and lipoxygenase expression and decreased oxylipids with known anti-inflammatory properties such as arachidonic acid-derived lipoxin A? (LXA?) and linoleic acid-derived 9-?oxo-octadecadienoic acid (9-oxoODE). Treating RAW 264.7 macrophages with LXA? or 9-oxoODE diminished oxidant-induced macrophage inflammatory response as indicated by decreased production of TNF?. The results show for the first time that selenoproteins are important for the balanced biosynthesis of pro- and anti-inflammatory oxylipids during inflammation. A better understanding of the Se-dependent control mechanisms governing oxylipid biosynthesis may uncover nutritional intervention strategies to counteract the harmful effects of uncontrolled inflammation due to oxylipids. PMID:24746836

Mattmiller, Sarah A; Carlson, Bradley A; Gandy, Jeff C; Sordillo, Lorraine M

2014-06-01

400

Effects of oxidized low density lipoproteins on arachidonic acid metabolism in smooth muscle cells.  

PubMed

The role of oxidized plasma lipoproteins in modifying arachidonic acid (AA) metabolism was studied in smooth muscle cells (SMC). Very low density lipoproteins (VLDL), unoxidized low density lipoproteins (LDLBHT) isolated with butylated hydroxytoluene (BHT), and oxidized LDL (LDLOXID) were separated from human serum. Thiobarbituric acid reactant (TBAR) levels were adjusted by saline incubations. Prostanoids in guinea pig SMC cultures were measured either by radioimmunoassay (RIA) or the isolation by high performance liquid chromatography (HPLC) of labeled prostanoids from SMC prelabeled with [14C]AA. Cell morphology and viability were studied by staining with Giemsa, nile red, and propidium iodide. VLDL and LDLBHT had little effect on prostanoid synthesis. Low-TBAR-LDLOXID enhanced total prostanoid levels and diminished the release of labeled prostanoids. Similar effects were found with exogenous free AA (unlabeled). Low-TBAR-LDLOXID did not affect the release of endogenous phospholipid AA as free AA. Synergism occurred between LDLOXID and exogenous free AA in prostanoid synthesis. Low-TBAR-LDLOXID evidently enhanced prostanoid levels in SMC both by supplying AA and by stimulating cyclooxygenase. High-TBAR-LDLOXID blocked prostanoid synthesis and enhanced cell death but time and pulse-recovery experiments showed that these effects were unrelated. High-TBAR-LDLOXID stimulated prostanoid synthesis when BHT was added to the incubation media. High-TBAR-LDLOXID also caused massive free AA release and the formation of many nonprostanoid derivatives. High-TBAR-LDLOXID evidently diminished overall prostanoid levels in SMC by inhibiting cyclooxygenase and at the same time stimulating AA release and the formation of other AA derivatives. PMID:2351866

Zhang, H F; Davis, W B; Chen, X S; Jones, K H; Whisler, R L; Cornwell, D G

1990-04-01

401

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

SciTech Connect

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.

Hoedemaker, M.; Weston, P.G.; Wagner, W.C. (Univ. of Illinois, Urbana (USA))

1991-01-01

402

Human Action Recognition Using Wireless Wearable In-Ear Microphone  

NASA Astrophysics Data System (ADS)

To realize the ubiquitous eating habits monitoring, we proposed the use of sounds sensed by an in-ear placed wireless wearable microphone. A prototype of wireless wearable in-ear microphone was developed by utilizing a common Bluetooth headset. We proposed a robust chewing action recognition algorithm which consists of two recognition stages: “chew-like” signal detection and chewing sound verification stages. We also provide empirical results on other action recognition using in-ear sound including swallowing, cough, belch, and etc. The average chewing number counting error rate of 1.93% is achieved. Lastly, chewing sound mapping is proposed as a new prototypical approach to provide an additional intuitive feedback on food groups to be able to infer the eating habits in their daily life context.

Nishimura, Jun; Kuroda, Tadahiro

403

Sensory Cells of the Fish Ear: A Hairy Enigma  

NASA Technical Reports Server (NTRS)

Analysis of the structure of the ears in teleost fishes has led to the tentative suggestion that otolithic endorgans may function differently, in different species. Recently, evidence has demonstrated different 'types' of sensory hair cells can be found in the ears of teleost fishes, and individual hair cell types are found in discrete regions of individual sensory, epithelia. The presence of multiple hair cell types in fishes provides strong support to the hypothesis of regional differences in the responses of individual otolithic sensory epithelia. The finding of hair cell types in fishes that closely resemble those found in amniote vestibular endorgans also suggests that hair cell heterogeneity arose earlier in the evolution of the vertebrate ear than previously thought.

Popper, A. N.; Saidel, W. M.

1995-01-01

404

Magnetically driven middle ear ossicles for optical measurement of vibrations in an ear with opened tympanic membrane.  

PubMed

Vibrations of the middle ear ossicles are easily measured by means of laser vibrometry. However, laser vibrometry requires free visual access to the object under investigation, and acquiring free visual access to the ossicles through the ear canal requires the removal of the tympanic membrane (TM), with the result that the ossicles can no longer be stimulated acoustically. To overcome this, we devised a new setup in which the ossicles can be driven magnetically. After measuring the response of the TM to an acoustic signal, we then remove it and attach a small magnet to the exposed manubrium (a part of the most lateral auditory ossicle, the malleus, which is normally attached to the TM). An electromagnetic excitation coil is then used to drive the magnet, and the output to the coil adjusted until the vibration of the manubrium, as measured by the vibrometer, matches that measured in response to the acoustic signal. Such a setup may have uses in research on middle ear mechanics, such as the measurement of nonlinearities in their response, as well as applications in the diagnosis of middle ear conditions such as the fixation of the ossicles by otosclerosis or in chronic otitis media. We describe our setup and discuss the viability of our method and its future clinical potential by presenting some measurements on an artificially fixated ear. PMID:24387412

Peacock, J; von Unge, M; Dirckx, J

2013-12-01

405

Magnetically driven middle ear ossicles for optical measurement of vibrations in an ear with opened tympanic membrane  

NASA Astrophysics Data System (ADS)

Vibrations of the middle ear ossicles are easily measured by means of laser vibrometry. However, laser vibrometry requires free visual access to the object under investigation, and acquiring free visual access to the ossicles through the ear canal requires the removal of the tympanic membrane (TM), with the result that the ossicles can no longer be stimulated acoustically. To overcome this, we devised a new setup in which the ossicles can be driven magnetically. After measuring the response of the TM to an acoustic signal, we then remove it and attach a small magnet to the exposed manubrium (a part of the most lateral auditory ossicle, the malleus, which is normally attached to the TM). An electromagnetic excitation coil is then used to drive the magnet, and the output to the coil adjusted until the vibration of the manubrium, as measured by the vibrometer, matches that measured in response to the acoustic signal. Such a setup may have uses in research on middle ear mechanics, such as the measurement of nonlinearities in their response, as well as applications in the diagnosis of middle ear conditions such as the fixation of the ossicles by otosclerosis or in chronic otitis media. We describe our setup and discuss the viability of our method and its future clinical potential by presenting some measurements on an artificially fixated ear.

Peacock, J.; von Unge, M.; Dirckx, J.

2013-12-01

406

Ion Channel Gene Expression in the Inner Ear  

PubMed Central

The ion channel genome is still being defined despite numerous publications on the subject. The ion channel transcriptome is even more difficult to assess. Using high-throughput computational tools, we surveyed all available inner ear cDNA libraries to identify genes coding for ion channels. We mapped over 100,000 expressed sequence tags (ESTs) derived from human cochlea, mouse organ of Corti, mouse and zebrafish inner ear, and rat vestibular end organs to Homo sapiens, Mus musculus, Danio rerio, and Rattus norvegicus genomes. A survey of EST data alone reveals that at least a third of the ion channel genome is expressed in the inner ear, with highest expression occurring in hair cell-enriched mouse organ of Corti and rat vestibule. Our data and comparisons with other experimental techniques that measure gene expression show that every method has its limitations and does not per se provide a complete coverage of the inner ear ion channelome. In addition, the data show that most genes produce alternative transcripts with the same spectrum across multiple organisms, no ion channel gene variants are unique to the inner ear, and many splice variants have yet to be annotated. Our high-throughput approach offers a qualitative computational and experimental analysis of ion channel genes in inner ear cDNA collections. A lack of data and incomplete gene annotations prevent both rigorous statistical analyses and comparisons of entire ion channelomes derived from different tissues and organisms. Electronic supplementary material The online version of this article (doi:10.1007/s10162-007-0082-y) contains supplementary material, which is available to authorized users. PMID:17541769

Sokolowski, Bernd H.A.; Morton, Cynthia C.; Giersch, Anne B.S.

2007-01-01

407

“Turkey Ear” as a Cutaneous Maniestation of Tuberculosis  

PubMed Central

Lupus vulgaris is the most common morphological variant of cutaneous tuberculosis. Classical lupus lesions are often seen in the head and neck region. Turkey ear is a clinically descriptive term, previously being used for the earlobe with reddish indurated plaque lesions, which recently can be a sign for lupus vulgaris. A 65-year-old man presented with lupus vulgaris of the earlobe. The diagnosis was confirmed by conventional laboratory investigations and the patient showed well response to antituberculous therapy. This is the second reported case of “turkey ear” as a manifestation of cutaneous tuberculosis. PMID:23248385

Küçükünal, Asl?; Ekmekçi, Tu?ba R; Sak?z, Damlanur

2012-01-01

408

Inner ear supporting cells: Rethinking the silent majority  

PubMed Central

Sensory epithelia of the inner ear contain two major cell types: hair cells and supporting cells. It has been clear for a long time that hair cells play critical roles in mechanoreception and synaptic transmission. In contrast, until recently the more abundant supporting cells were viewed primarily as serving primarily structural and homeostatic functions. In this review we discuss the growing information about the roles that supporting cells play in the development, function and maintenance of the inner ear, their activities in pathological states, their potential for hair cell regeneration, and the mechanisms underlying these processes. PMID:23545368

Wan, Guoqiang; Corfas, Gabriel; Stone, Jennifer S

2014-01-01

409

Merkel cell carcinoma arising in the ear canal.  

PubMed

A case of rare tumor, Merkel cell carcinoma, located in the ear canal of a 25-year-old woman is presented. A polypoid tumor mass was extirpated, and tympanoplasty was done at the first operation, whereas at the second operation, all the bones of the ear canal were removed. Epitympanum and cavum were filled with tumor, and the tumor mass was removed in toto. The histopathology and immunohistochemical staining characteristics of tumor confirmed the presence of Merkel cell tumor. Postoperatively, radiation therapy to the tumor bed was completed. There was no clinical or radiographic evidence of recurrence or metastasis of Merkel cell tumor for 3 years. PMID:18387993

Petkovi?, Marija; Krstulja, Mira; Radic, Jelena; Zamolo, Gordana; Muhvi?, Damir; Lovasic, Ingrid; Kujundzic, Milodar; Franko, Artur

2008-07-01

410

Energy localization and frequency analysis in the locust ear  

PubMed Central

Animal ears are exquisitely adapted to capture sound energy and perform signal analysis. Studying the ear of the locust, we show how frequency signal analysis can be performed solely by using the structural features of the tympanum. Incident sound waves generate mechanical vibrational waves that travel across the tympanum. These waves shoal in a tsunami-like fashion, resulting in energy localization that focuses vibrations onto the mechanosensory neurons in a frequency-dependent manner. Using finite element analysis, we demonstrate that two mechanical properties of the locust tympanum, distributed thickness and tension, are necessary and sufficient to generate frequency-dependent energy localization. PMID:24196693

Malkin, Robert; McDonagh, Thomas R.; Mhatre, Natasha; Scott, Thomas S.; Robert, Daniel

2014-01-01

411

To Have an Ear: Music and the Otological Experience.  

PubMed

This essay analyzes the historical development of otology in relation to music. It illustrates the integral role of music perception and appreciation in the study of hearing, where hearing operates not simply as a scientific phenomenon but signifies particular meaningful experiences in society. The four historical moments considered-Helmholtz's piano-keyed cochlea, the ear phonautograph, the hearing aid, and the cochlear implant-show how the sounds, perceptions, and instruments of music have mediated and continue to mediate our relationships with hearing. To have an ear, one does not just bear a physiological hearing mechanism; one experiences the aesthetics of musical sound. PMID:24994077

Sattar, Atia

2014-07-01

412

Inflammatory cytokines enhance muscarinic-mediated arachidonic acid release through p38 mitogen-activated protein kinase in A2058 cells.  

PubMed

The human melanoma cell line A2058 expresses the Gq-coupled M5 subtype of muscarinic receptor. Stimulation with the cholinergic agonist, carbachol, induces a dose-dependent increase in arachidonic acid release. The carbachol-induced arachidonate release is potentiated two- to threefold by pretreatment of A2058 cells with either of the inflammatory cytokines, tumor necrosis factor-alpha or interleukin-1beta . Cytokine-induced enhancement of muscarinic-mediated arachidonic acid release peaks near 1 h. Western analysis suggests that both cytokines are capable of activating the nuclear factor-kappaB (NF-kappaB) and p38 mitogen-activated protein kinase (MAPK) pathways. Anisomycin (1 microM) treatment mimics the cytokine-induced enhancement of arachidonic acid production and activates the p38 MAPK pathway, but does not activate the NF-kappaB pathway. Furthermore, pre-treatment of A2058 cells with the putative p38 MAPK inhibitor, SB202190, ablates the cytokine-dependent augmentation without interfering with the muscarinic-mediated arachidonic acid release in untreated cells. Moreover, cytokine treatment does not affect other M5-coupled pathways (e.g., phospholipase C activity or intracellular Ca2+ mobilization), suggesting that p38 MAPK activation principally modulates muscarinic-mediated phospholipase A2 activity. Finally, in primary cultures of cells taken from rat cerebellum, key aspects of this finding are repeated in cultures enriched for glia, but not in cultures enriched for granule neurons. PMID:10800946

Wood, M W; Segal, J A; Mark, R J; Ogden, A M; Felder, C C

2000-05-01

413

Short Communication Functional ear (a)symmetry in brainstem neural activity relevant to encoding  

E-print Network

Short Communication Functional ear (a)symmetry in brainstem neural activity relevant to encoding Keywords: Auditory Human Brainstem Pitch Language Mandarin Chinese Fundamental frequency-following response areas. This experiment investigates whether ear asymmetries vary in brainstem representation of pitch

Dasgupta, Dipankar

414

Coupler-related real ear gain. Interaction between subject and hearing aid type.  

PubMed

In order to select hearing aids with a highly predictable real ear gain, in situ gain and compliance through the individual ear mould were measured on 8 normal-hearing subjects. The latter were chosen in order to reduce gain variation caused by various pathological conditions of the ear. All behind-the-ear aids commonly used in Sweden and one in-the-ear aid were studied. One sample of each hearing aid type was tested and the subjects had identical ear moulds. Hence, the variables were hearing aid type and subject. The study showed wide intra-subject coupler-related real ear gain variation (30 dB). Most of the aids showed a distinct correlation between coupler-related overall gain, and mould compliance. Some of the aids gave more uniform real ear gain, i.e. low interaction between subject and frequency-dependent gain. These results are elucidated by measuring the aid's acoustic output impedance. PMID:1585125

Berninger, E; Ovegård, A; Svärd, I

1992-01-01

415

Effects of Intrathecally Administered Aminoglycoside Antibiotics, Calcium-Channel Blockers, Nickel and Calcium on Acetic Acid-Induced Writhing Test in Mice  

Microsoft Academic Search

1.Antinociceptive effects of intrathecally administered aminoglycoside antibiotics, calcium-channel blockers, nickel and calcium ions on the acetic acid–induced writhing test in mice were examined.2.Neomycin (0.5–20.0 ?g\\/mouse) gentamicin (5–40 ?g\\/mouse), nicardipine, diltiazem and verapamil (0.5–80.0 ?g\\/mouse) and calcium ions (0.02–1.0 ?mol\\/mouse) exerted a dose-dependent antinociceptive activity on the acetic acid–induced writhing test. Nickel ions ( 2.5, 5.0 and 10.0 ?mol\\/mouse) were found

Ahmet Do?rul; Özgür Ye?ilyurt

1998-01-01

416

Reliability of real ear insertion gain in behind-the-ear hearing aids with different coupling systems to the ear canal  

PubMed Central

Objective The last decade has offered a multitude of instant fit coupling systems to be fitted with behind-the-ear (BTE) hearing aids. The impact of these designs on the reliability of real ear measurements (REMs) has not been reported. The purpose of this study was to obtain REM reliability data for instant fit coupling systems. Design REM reliability data was obtained for four different instant-fit coupling systems and for standard size 13 tubing and custom earmolds. REMs were performed for all five coupling systems two times and by two examiners. Study sample Ten normal-hearing individuals (20 ears) served as participants. Results The REM test-retest reliability is high for the four instant fit coupling systems as well as for the custom earmolds. The REM inter-examiner reliability is high for three of the four instant fit coupling systems. Conclusions Carrying out REMs with instant fit coupling systems appears to be fundamentally no different than performing REMs with conventional hearing aids. For either, care should be taken in probe tube placement in terms of insertion depth and maintaining the probe tube placement, and other best practices regarding test environment and test setup should be observed. PMID:23301659

2013-01-01

417

Formal syntheses of (±)-platensimycin and (±)-platencin via a dual-mode Lewis acid induced cascade cyclization approach.  

PubMed

A mild and efficient dual-mode Lewis acid induced Diels-Alder (DA)/carbocyclization cascade cyclization reaction has been developed for construction of the tricyclic core of ent-kaurenoids in one pot with the aid of a theoretical study on the ?,?-Lewis acidities of a variety of Lewis acids. With ZnBr2 as the dual-mode Lewis acid, a series of substituted enones and dienes underwent DA/carbocyclization cascade cyclization reaction smoothly at room temperature and provided the tricyclic cyclized products in one pot with good yields and high diastereoselectivity. The tricyclic cyclized product has been successfully utilized as a common intermediate for formal syntheses of (±)-platensimycin and (±)-platencin. PMID:23859063

Zhu, Lizhi; Zhou, Congshan; Yang, Wei; He, Shuzhong; Cheng, Gui-Juan; Zhang, Xinhao; Lee, Chi-Sing

2013-08-16

418

Antitussive Activity of the Water-Extracted Carbohydrate Polymer from Terminalia chebula on Citric Acid-Induced Cough  

PubMed Central

Terminalia chebula, a medicinal plant, is widely used in the management of various diseases. As the water extract of its dried ripe fruit is a frequently used preparation, we decided to look for bioactive polysaccharide in this extract. We demonstrate that the obtained polysaccharide fraction, CP, contained a highly branched arabinogalactan protein having a (1 ? 3)-, (1 ? 6)- and (1 ? 3, 6)-linked ?-D-Galp together with (1 ? 5)- and (1 ? 3)-linked ?-L-Araf and nonreducing end units of ?-L-Araf. This polymer possesses strong antitussive property. Our results showed that the number of citric acid-induced cough efforts decreased significantly after the oral application of polysaccharide fraction in a dose of 50?mg?kg?1 body weight. Its antitussive efficacy was higher than cough suppressive effect of standard drug codeine. Therefore, traditional aqueous extraction method provides a major polysaccharide, which induces a pharmacological effect: this could represent an attractive approach in phytotherapeutic managements. PMID:23878602

Chatterjee, Udipta Ranjan; Majee, Sujay Kumar; Ray, Bimalendu

2013-01-01

419

Relating middle-ear acoustic performance to body size in the cat family: measurements and models  

Microsoft Academic Search

Is the acoustic performance of the mammalian middle ear dependent on body size? We focus on the cat family, because of its\\u000a qualitatively uniform (and distinctive) middle-ear structure, large size range, and the extensive data available from domestic\\u000a cats which provide a framework for relating middle-ear acoustics to structure. We report measurements of acoustic admittance\\u000a in 17 live adult ears

G. T. Huang; J. J. Rosowski; W. T. Peake

2000-01-01

420

Pneumococcal meningitis threshold model: a potential tool to assess infectious risk of new or existing inner ear surgical interventions .  

E-print Network

??Hypothesis: A minimal threshold of Streptococcus pneumoniae is required to induce meningitis in healthy animals for intraperitoneal (hematogenous), middle ear, and inner ear inoculations, and… (more)

Wei, Benjamin P. C.

2006-01-01

421

FOOD HABITS AND HUNTING RANGES OF SHORT-EARED OWLS  

Microsoft Academic Search

ABSTRCT.--The diet of the Short-eared Owl (Asio flammeus) was quantified by analyzing 400 pellets collected in two agricultural landscapes of southern Chile (Osorno and Chahuilco). Diet composition fluctuated seasonally and included several species of small mammals, birds, and insects. Almost 80% of the annual biomass consumed was from two rodent species (Akodon olivaceus and Rattus norvegicus) and of a bird

DAVID R. MARTINEZ; RICARDO A. FIGUEROA; CARMEN L. OCAMPO; FABIAN M. JAKSIC

422

An outbreak of erysipelas in eared grebes (Podiceps nigricollis).  

PubMed

An outbreak of erysipelas killed an estimated 5,000 aquatic birds on Great Salt Lake (Utah) in late November, 1975. Although several thousand ducks and gulls were using the lake, at least 99 percent of the victims were eared grebes. A hypothetical explanation for the selective mortality is offered. PMID:16502704

Jensen, W I; Cotter, S E

1976-10-01

423

Quality Management in Middle Ear Surgery: Controversies Regarding Preoperative Imaging  

Microsoft Academic Search

Today a large variety of different imaging techniques are available for middle ear investigation. However, imaging is not suitable to give essential information in every case on the surgical strategy to be chosen. This article discusses the most frequent indications for preoperative imaging and the relevant techniques. CT scanning, MRI and rotational tomography are taken into consideration as well as

T. Zahnert; C. Offergeld

2010-01-01

424

Prevalence of red ear syndrome in juvenile primary headaches  

Microsoft Academic Search

Background: Previous studies have suggested a relationship between ‘red ear syndrome’ (RES) and pediatric migraine. Aims of this study were (i) to assess the frequency, specificity and sensitivity of RES in a population of pediatric migraineurs and (ii) to establish the pathophysiological mechanisms of RES associated with migraine.Methods and results: A total of 226 children suffering from headache (aged 4—17

V. Raieli; A. Compagno; F. Brighina; G. La Franca; D. Puma; D. Ragusa; G. Savettieri; M. DAmelio

2011-01-01

425

Ion Homeostasis in the Ear: Mechanisms, Maladies, and Management  

PubMed Central

Purpose of Review Describe ion and water homeostatic mechanisms in the inner ear, how they are compromised in hearing disorders, and what treatments are employed to restore auditory function. Recent Findings The ion and water transport functions in the inner ear help maintain the proper endolymph K+ concentration required for hair cell function. Gene defects and idiopathic alterations in these transport functions cause hearing loss, but often the underlying cause is unknown. Current therapies largely involve glucocorticoid treatment, although the mechanisms of restoration are often undeterminable. Recent studies of these ion homeostatic functions in the ear are characterizing their cellular and molecular control. It is anticipated that future management of these hearing disorders will be more targeted to the cellular processes involved and improve the likelihood of hearing recovery. Summary A better understanding of the ion homeostatic processes in the ear will permit more effective management of their associated hearing disorders. Sufficient insight into many homeostatic hearing disorders has now been attained to usher in a new era of better therapies and improved clinical outcomes. PMID:20693900

Trune, Dennis R.

2010-01-01

426

Maize starch fine structures affected by ear developmental temperature  

Microsoft Academic Search

Growing temperature is known to affect the grain yield and quality of maize. Two genetically unrelated normal dent maize inbreds, ICI63 and ICI92, with different heterotic backgrounds were grown in a greenhouse with the ears wrapped in temperature control devices set at 25 and 35 °C during the grain-filling period. Grain yield, kernel weight, and kernel density were less for

Ting-jang Lu; Jay-lin Jane; Peter L. Keeling; George W. Singletary

1996-01-01

427

Future Approaches for Inner Ear Protection and Repair  

ERIC Educational Resources Information Center

Health care professionals tending to patients with inner ear disease face inquiries about therapy options, including treatments that are being developed for future use but not yet available. The devastating outcome of sensorineural hearing loss, combined with the permanent nature of the symptoms, make these inquiries demanding and frequent. The…

Shibata, Seiji B.; Raphael, Yehoash

2010-01-01

428

Purdue extensionAspergillus Ear Rot Purdue extension  

E-print Network

causes Aspergillus ear rot, one of the most important diseases in corn. The fungus pro- duces a mycotoxin to livestock 3. Mycotoxin testing 4. How to minimize losses and handle diseased grain after harvest 5. How these levels. detecting Mycotoxins An ultraviolet lamp, or black light, is often used as an initial screen

Holland, Jeffrey

429

EARS: Toward Fast Analysis of 3D Human  

E-print Network

Team, US Army Natick Soldier RDEC 1 Kansas St, Natick, MA 01760, USA ABSTRACT We present the Enhanced-time feedback on the quality of a human body scan mesh. We have tested EARS on a set of 100 female and 100 male. The Ergonomics team at the Natick Soldier RDEC is conducting a survey of anthropometrics for the soldier

430

Biology and migration of Eared Grebes at the Salton Sea  

Microsoft Academic Search

The Eared Grebe (Podiceps nigricollis Brehm) is the North American bird species most closely associated with highly saline habitats, and in winter and early spring it is the most abundant waterbird at the Salton Sea. During the fall, the great majority of the North American population stages at hypersaline lakes in the Great Basin, departing in early winter for wintering

Joseph R. Jehl; Robert L. McKernan

2002-01-01

431

ORIGINAL COMMUNICATION Imaging Microscopy of the Middle and Inner Ear  

E-print Network

present high-resolution MicroCT images of the middle ear and bony labyrinth to highlight the utility:607­612 (2004) © 2004 Wiley-Liss, Inc. #12;properly in the microCT scanner. The specimen was scanned without decalcification or additional fixation. MicroCT scanning differs from clinical scanning in that the object

Allen, Jont

432

Acetone Photophysics at ear Critical to Supercritical Conditions  

E-print Network

Acetone Photophysics at ear Critical to Supercritical Conditions T. Tran* , Y. Kochar* , J-0150 The photophysics of vapor and liquid acetone are experimentally examined from subcritical to supercritical conditions with 266 nm excitation, motivated by an interest in using acetone to study transcritical fuel

Seitzman, Jerry M.

433

The fluid mechanics of the inner-ear disorder BPPV  

Microsoft Academic Search

The inner ear of mammals contains fluid-filled semi-circular canals with a flexible sensory membrane (called a cupula) which detects rotational acceleration. Benign Paroxysmal Positional Vertigo (BPPV) is one of the most common disorders of this system diagnosed today, and is characterized by symptoms of dizziness and nausea brought on by sudden changes in head orientation. BPPV is believed to have

Michael Weidman; Todd Squires; Howard Stone

2001-01-01

434

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

Code of Federal Regulations, 2011 CFR

...Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR...nose, or throat area. The bur consists of a carbide cutting tip on a metal shank or a coating of diamond on a metal...

2011-04-01

435

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

Code of Federal Regulations, 2010 CFR

...Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR...nose, or throat area. The bur consists of a carbide cutting tip on a metal shank or a coating of diamond on a metal...

2010-04-01

436

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

...Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR...nose, or throat area. The bur consists of a carbide cutting tip on a metal shank or a coating of diamond on a metal...

2014-04-01

437

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

Code of Federal Regulations, 2012 CFR

...Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR...nose, or throat area. The bur consists of a carbide cutting tip on a metal shank or a coating of diamond on a metal...

2012-04-01

438

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

Code of Federal Regulations, 2013 CFR

...Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES EAR...nose, or throat area. The bur consists of a carbide cutting tip on a metal shank or a coating of diamond on a metal...

2013-04-01

439

EARS buoy applications by LADC: I. marine animal acoustics  

Microsoft Academic Search

Littoral Acoustic Demonstration Center (LADC) scientists have investigated sperm and beaked whale clicks as recorded on Environmental Acoustic Recording System (EARS) buoys to analyze whale behavior and the possibility of identifying individual whales acoustically. The research began in 2001 and continues through the present. LADC has conducted three experiments in the northern Gulf of Mexico and participated with the Naval

George E. Ioup; Juliette W. Ioup; Lisa A. Pflug; Arslan M. Tashmukhambetov; Natalia A. Sidorovskaia; Philip Schexnayder; Christopher O. Tiemann; Alan Bernstein; Stan A. Kuczaj; Grayson H. Rayborn; Joal J. Newcomb; R. Carlson; A. Ekimov

2009-01-01

440

How the Ear Works: Nature's Solutions for Listening.  

ERIC Educational Resources Information Center

A history of hearing and a review of the physics of sound is followed by an overview of how the ear works. The outer hair cell is the focus of particular attention because of its central role in the conversion of sound energy into neural energy used by the brain. Contains a list of recommended resources. (CR)

Brownell, William E.

1997-01-01

441

Redundant functions of Rac GTPases in inner ear morphogenesis  

PubMed Central

Development of the mammalian inner ear requires coordination of cell proliferation, cell fate determination and morphogenetic movements. While significant progress has been made in identifying developmental signals required for inner ear formation, less is known about how distinct signals are coordinated by their downstream mediators. Members of the Rac family of small GTPases are known regulators of cytoskeletal remodeling and numerous other cellular processes. However, the function of Rac GTPases in otic development is largely unexplored. Here, we show that Rac1 and Rac3 redundantly regulate many aspects of inner ear morphogenesis. While no morphological defects were observed in Rac3-/- mice, Rac1CKO; Rac3-/- double mutants displayed enhanced vestibular and cochlear malformations compared to Rac1CKO single mutants. Moreover, in Rac1CKO; Rac3-/- mutants, we observed compromised E-cadherin-mediated cell adhesion, reduced cell proliferation and increased cell death in the early developing otocyst, leading to a decreased size and malformation of the membranous labyrinth. Finally, cochlear extension was severely disrupted in Rac1CKO; Rac3-/-mutants, accompanied by a loss of epithelial cohesion and formation of ectopic sensory patches underneath the cochlear duct. The compartmentalized expression of otic patterning genes within the Rac1CKO; Rac3-/- mutant otocyst was largely normal, however, indicating that Rac proteins regulate inner ear morphogenesis without affecting cell fate specification. Taken together, our results reveal an essential role for Rac GTPases in coordinating cell adhesion, cell proliferation, cell death and cell movements during otic development. PMID:22182523

Grimsley-Myers, Cynthia M.; Sipe, Conor W.; Wu, Doris K.; Lu, Xiaowei

2012-01-01

442

Intratympanic gentamicin therapy for vertigo in nonserviceable ears  

Microsoft Academic Search

Purpose: Intratympanic ototoxic agents have become a widely accepted means of managing vertigo in patients with Meniere's disease while preserving residual hearing. We investigated expanding the indications for intratympanic gentamicin to include control of vertigo in patients without serviceable hearing in the involved ear caused by a variety of end-organ pathologies. Materials and Methods: We present a retrospective series of

Paul W Bauer; C. Bruce MacDonald; L. Clarke Cox

2001-01-01

443

Baby corn, green ear, and grain yield of corn cultivars  

Microsoft Academic Search

Most maize cultivars have been developed for grain production. Because superior cultivars may differ in their exploiting purposes, interest has been demonstrated for the evaluation of corn cultivars with regard to their baby corn, green ear, and grain yields production ability. In the present work ten corn cultivars (AG 405, AG 1051, AG 2060, AG 6690, AG 7575, AG 8080,

Itala Paula de C. Almeida; Paulo Sérgio L. e Silva; Maria Z. de Negreiros; Zenaide Barbosa

2005-01-01

444

High expression of arachidonate 15-lipoxygenase and proinflammatory markers in human ischemic heart tissue  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer We found a 17-fold upregulation of ALOX15 in the ischemic heart. Black-Right-Pointing-Pointer Incubation of human muscle cells in hypoxia showed a 22-fold upregulation of ALOX15. Black-Right-Pointing-Pointer We observed increased levels of proinflammatory markers in ischemic heart tissue. Black-Right-Pointing-Pointer Suggesting a link between ischemia and inflammation in ischemic heart biopsies. -- Abstract: A common feature of the ischemic heart and atherosclerotic plaques is the presence of hypoxia (insufficient levels of oxygen in the tissue). Hypoxia has pronounced effects on almost every aspect of cell physiology, and the nuclear transcription factor hypoxia inducible factor-1{alpha} (HIF-1{alpha}) regulates adaptive responses to low concentrations of oxygen in mammalian cells. In our recent work, we observed that hypoxia increases the proinflammatory enzyme arachidonate 15-lipoxygenase (ALOX15B) in human carotid plaques. ALOX15 has recently been shown to be present in the human myocardium, but the effect of ischemia on its expression has not been investigated. Here we test the hypothesis that ischemia of the heart leads to increased expression of ALOX15, and found an almost 2-fold increase in HIF-1{alpha} mRNA expression and a 17-fold upregulation of ALOX15 mRNA expression in the ischemic heart biopsies from patients undergoing coronary bypass surgery compared with non ischemic heart tissue. To investigate the effect of low oxygen concentration on ALOX15 we incubated human vascular muscle cells in hypoxia and showed that expression of ALOX15 increased 22-fold compared with cells incubated in normoxic conditions. We also observed increased mRNA levels of proinflammatory markers in ischemic heart tissue compared with non-ischemic controls. In summary, we demonstrate increased ALOX15 in human ischemic heart biopsies. Furthermore we demonstrate that hypoxia increases ALOX15 in human muscle cells. Our results yield important insights into the underlying association between hypoxia and inflammation in the human ischemic heart disease.

Magnusson, Lisa U.; Lundqvist, Annika [Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg (Sweden)] [Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg (Sweden); Asp, Julia [Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg (Sweden)] [Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg (Sweden); Synnergren, Jane [Systems Biology Research Center, School of Life Sciences, University of Skoevde, Skoevde (Sweden)] [Systems Biology Research Center, School of Life Sciences, University of Skoevde, Skoevde (Sweden); Johansson, Cecilia Thalen [Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg (Sweden)] [Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg (Sweden); Palmqvist, Lars [Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg (Sweden)] [Department of Clinical Chemistry and Transfusion Medicine, Institute of Biomedicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg (Sweden); Jeppsson, Anders [Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg (Sweden)] [Department of Cardiothoracic Surgery, Sahlgrenska University Hospital, Gothenburg (Sweden); Hulten, Lillemor Mattsson, E-mail: Lillemor.Mattsson@wlab.gu.se [Sahlgrenska Center for Cardiovascular and Metabolic Research, Wallenberg Laboratory, Department of Molecular and Clinical Medicine, Institute of Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg (Sweden)

2012-07-27

445

Regulation of the arachidonic acid mobilization in macrophages by combustion-derived particles  

PubMed Central

Background Acute exposure to elevated levels of environmental particulate matter (PM) is associated with increasing morbidity and mortality rates. These adverse health effects, e.g. culminating in respiratory and cardiovascular diseases, have been demonstrated by a multitude of epidemiological studies. However, the underlying mechanisms relevant for toxicity are not completely understood. Especially the role of particle-induced reactive oxygen species (ROS), oxidative stress and inflammatory responses is of particular interest. In this in vitro study we examined the influence of particle-generated ROS on signalling pathways leading to activation of the arachidonic acid (AA) cascade. Incinerator fly ash particles (MAF02) were used as a model for real-life combustion-derived particulate matter. As macrophages, besides epithelial cells, are the major targets of particle actions in the lung murine RAW264.7 macrophages and primary human macrophages were investigated. Results The interaction of fly ash particles with macrophages induced both the generation of ROS and as part of the cellular inflammatory responses a dose- and time-dependent increase of free AA, prostaglandin E2/thromboxane B2 (PGE2/TXB2), and 8-isoprostane, a non-enzymatically formed oxidation product of AA. Additionally, increased phosphorylation of the mitogen-activated protein kinases (MAPK) JNK1/2, p38 and ERK1/2 was observed, the latter of which was shown to be involved in MAF02-generated AA mobilization and phosphorylation of the cytosolic phospolipase A2. Using specific inhibitors for the different phospolipase A2 isoforms the MAF02-induced AA liberation was shown to be dependent on the cytosolic phospholipase A2, but not on the secretory and calcium-independent phospholipase A2. The initiation of the AA pathway due to MAF02 particle exposure was demonstrated to depend on the formation of ROS since the presence of the antioxidant N-acetyl-cysteine (NAC) prevented the MAF02-mediated enhancement of free AA, the subsequent conversion to PGE2/TXB2 via the induction of COX-2 and the ERK1/2 and JNK1/2 phosphorylation. Finally we showed that the particle-induced formation of ROS, liberation of AA and PGE2/TXB2 together with the phosphorylation of ERK1/2 and JNK1/2 proteins was decreased after pre-treatment of macrophages with the metal chelator deferoxamine mesylate (DFO). Conclusions These results indicate that one of the primary mechanism initiating inflammatory processes by incinerator fly ash particles seems to be the metal-mediated generation of ROS, which triggers via the MAPK cascade the activation of AA signalling pathway. PMID:21810225

2011-01-01

446

Arachidonic acid reduces the stress response of gilthead seabream Sparus aurata L.  

PubMed

In this study the influence of the dietary level of the fatty acid arachidonic acid (ArA, 20:4n-6) was determined on the acute stress response and osmoregulation of adult gilthead seabream Sparus aurata L. Seabream were fed a diet containing either 0.9% or 2.4% of total fatty acids as ArA for 18 days before being subjected to a 5 min period of net confinement. Prior to this stressor, a subgroup of fish from both dietary treatment groups was treated with acetylsalicylic acid (ASA), an irreversible blocker of cyclooxygenase (COX). This would indicate whether any effects were caused by an enhanced synthesis of prostaglandins derived from ArA. The highest ArA levels were found in the kidneys, and these were further enhanced by dietary ArA-supplementation. In gill tissues, there were significant changes in all selected fatty acid classes 24 h after confinement, except for the docosahexaenoic acid (DHA, 22:6n-3): eicosapentaenoic acid (EPA, 20:5n-3) ratio. ArA feeding strongly reduced the cortisol response to confinement, which was partially counteracted by ASA treatment. ArA also attenuated the stress-associated increase in plasma osmolality and, in combination with ASA, enhanced the osmolality and plasma chloride levels, but reduced plasma sodium levels after confinement. Furthermore, ArA enhanced the branchial Na(+), K(+)-ATPase activity both before and after confinement, whereas feeding ASA diminished this effect. It appeared that the effects of ArA-supplementation could not always be ascribed to an increase in prostaglandin synthesis. It is advisable to determine the long-term effects of replacing fish oils in commercial diets with vegetable oils that contain no long-chain fatty acids, particularly in carnivorous/marine species with low fatty acid elongation and desaturation activities. The effects of a low dietary intake of ArA (and other polyunsaturated fatty acids) should be studied over a longer term, taking into account any consequences for the health of the fish. PMID:15326218

Van Anholt, R D; Spanings, F A T; Koven, W M; Nixon, O; Wendelaar Bonga, S E

2004-09-01

447

Effects of physical conditioning on lipids and arachidonic acid metabolites in untrained boys: a longitudinal study.  

PubMed

In addition to a variety of lipids, 2 products of the arachidonic acid cascade, prostacyclin and thromboxane, are involved in the pathogenesis of atherosclerosis as a result of their effects on platelet function and on the vascular endothelium. The aim of the present investigation was to ascertain if a sub-maximal 8 week endurance training period followed by a 4 week detraining period would have any effects on high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), triglycerides (TG), 2,3-dinor-6-keto-prostaglandin F(1alpha) (2,3-dinor-6-keto-PGF(1alpha)), the urinary metabolite of prostacyclin, 2,3-dinor-thromboxane B2 (2,3-dinor-TXB2), the urinary metabolite of thromboxane, and the ratios of TC to HDL-C and of 2,3 dinor-6-keto-PGF(1alpha) to 2,3-dinor-TXB2. Thirty-eight boys aged 10-14 were randomly divided into exercise (n = 21) and control (n = 17) groups. The exercise group trained on a bicycle ergometer 4 times/week, 1 h/session, at 80% of their physical working capacity at a heart rate of 170 beats/min (PWC(170)), for 8 weeks. The control group did not participate in any specific physical exercise program. The results showed that relative to the control group, the exercise group had a significant increase in HDL-C and 2,3-dinor-6-keto-PGF(1alpha) concentrations at the end of the 4th (p < 0.05 and p < 0.001, respectively) and the 8th week (p < 0.01 and p < 0.001) of training, respectively; a significant increase in the 2,3 dinor-6-keto-PGF(1alpha) - 2,3-dinor-TXB2 ratio (p < 0.05 and p < 0.01 at the same intervals); a significant decrease in TG at the end of the 8th week of training (p < 0.05); and a significant decrease in the TC--HDL-C ratio at the end of the 4th (p < 0.05) and 8th weeks of training (p < 0.001). PMID:16900233

Stergioulas, Apostolos Thomas; Filippou, Dimitrios Konstantinos

2006-08-01

448

Arachidonate-regulated Ca(2+) influx in human airway smooth muscle.  

PubMed

Plasma membrane Ca(2+) influx, especially store-operated Ca(2+) entry triggered by sarcoplasmic reticulum (SR) Ca(2+) release, is a key component of intracellular calcium concentration ([Ca(2+)]i) regulation in airway smooth muscle (ASM). Agonist-induced Ca(2+) oscillations in ASM that involve both influx and SR mechanisms have been previously demonstrated. In nonexcitable cells, [Ca(2+)]i oscillations involve Ca(2+) influx via arachidonic acid (AA) -stimulated channels, which show similarities to store-operated Ca(2+) entry, although their molecular identity remains undetermined. Little is known about AA-regulated Ca(2+) channels or their regulation in ASM. In enzymatically dissociated human ASM cells loaded with the Ca(2+) indicator, fura-2, AA (1-10 ?M) triggered [Ca(2+)]i oscillations that were inhibited by removal of extracellular Ca(2+). Other fatty acids, such as the diacylglycerol analog, 1-oleoyl-2-acetyl-SN-glycerol, oleic acid, and palmitic acid (10 ?M each), failed to elicit similar [Ca(2+)]i responses. Preincubation with LaCl3 (1 ?M or 1 mM) inhibited AA-induced oscillations. Inhibition of receptor-operated channels (SKF96,365 [10 ?M]), lipoxygenase (zileuton [10 ?M]), or cyclooxygenase (indomethacin [10 ?M]) did not affect oscillation parameters. Inhibition of SR Ca(2+) release (ryanodine [10 ?M] or inositol 1,4,5-trisphosphate receptor inhibitor, xestospongin C [1 ?M]) decreased [Ca(2+)]i oscillation frequency and amplitude. Small interfering RNA against caveolin-1, stromal interaction molecule 1, or Orai3 (20 nM each) reduced the frequency and amplitude of AA-induced [Ca(2+)]i oscillations. In ASM cells derived from individuals with asthma, AA increased oscillation amplitude, but not frequency. These results are highly suggestive of a novel AA-mediated Ca(2+)-regulatory mechanism in human ASM, reminiscent of agonist-induced oscillations. Given the role of AA in ASM intracellular signaling, especially with inflammation, AA-regulated Ca(2+) channels could potentially contribute to increased [Ca(2+)]i in diseases such asthma. PMID:24471656

Thompson, Michael A; Prakash, Y S; Pabelick, Christina M

2014-07-01

449

21 CFR 344.52 - Labeling of ear drying aid drug products.  

Code of Federal Regulations, 2013 CFR

...in bold type] [bullet] ear drainage or discharge [bullet] pain, irritation, or rash in the ear [bullet] had ear surgery...a doctor if [in bold type] irritation (too much burning) or pain occurs.” (d) Directions. The labeling of the product...

2013-04-01

450

21 CFR 344.52 - Labeling of ear drying aid drug products.  

...in bold type] [bullet] ear drainage or discharge [bullet] pain, irritation, or rash in the ear [bullet] had ear surgery...a doctor if [in bold type] irritation (too much burning) or pain occurs.” (d) Directions. The labeling of the product...

2014-04-01

451

21 CFR 344.52 - Labeling of ear drying aid drug products.  

Code of Federal Regulations, 2010 CFR

...in bold type] [bullet] ear drainage or discharge [bullet] pain, irritation, or rash in the ear [bullet] had ear surgery...a doctor if [in bold type] irritation (too much burning) or pain occurs.” (d) Directions. The labeling of the product...

2010-04-01

452

21 CFR 344.52 - Labeling of ear drying aid drug products.  

Code of Federal Regulations, 2011 CFR

...in bold type] [bullet] ear drainage or discharge [bullet] pain, irritation, or rash in the ear [bullet] had ear surgery...a doctor if [in bold type] irritation (too much burning) or pain occurs.” (d) Directions. The labeling of the product...

2011-04-01

453

Ear-Canal Reflectance, Umbo Velocity, and Tympanometry in Normal-Hearing Adults  

E-print Network

Ear-Canal Reflectance, Umbo Velocity, and Tympanometry in Normal-Hearing Adults John J. Rosowski,1. Halpin,4 and Saumil N. Merchant1,2,3 Objective: This study compares measurements of ear-canal reflectance (ECR) to other objective measurements of middle ear function including audiometry, umbo velocity (VU

Allen, Jont

454

Audiometric Predictions Using Stimulus-Frequency Otoacoustic Emissions and Middle Ear  

E-print Network

Audiometric Predictions Using Stimulus-Frequency Otoacoustic Emissions and Middle Ear Measurements or moderate-severe, and correlate with pure-tone thresholds in a population of adults with normal middle ear function. Other goals are to determine if middle ear function as assessed by wideband acoustic transfer

Allen, Jont

455

ARTICLE doi:10.1038/nature09921 Transitional mammalian middle ear from  

E-print Network

ARTICLE doi:10.1038/nature09921 Transitional mammalian middle ear from a new Cretaceous Jehol the dentary and the detached ossicles during mammalian evolution. This transitional mammalian middle ear narrows the morphological gap between the mandibular middle ear in basal mammaliaforms and the definitive

Sullivan, Jack

456

Measurements of human middle ear forward and reverse acoustics: Implications for otoacoustic emissions  

E-print Network

Measurements of human middle ear forward and reverse acoustics: Implications for otoacoustic and California Ear Institute at Stanford, 801 Welch Road, Palo Alto, California 94304 Received 11 July 2002; revised 1 February 2003; accepted 4 February 2003 Middle and inner ears from human cadaver temporal bones

Allen, Jont

457

Steps for Using the EAR Part 732-page 1 Export Administration Regulations  

E-print Network

Steps for Using the EAR Part 732-page 1 Export Administration Regulations §732.1 STEPS OVERVIEW (a)(1) Introduction In this part, references to the EAR are references to 15 CFR chapter VII, subchapter C. This part is intended to help you determine your obligations under the EAR by listing logical

Bernstein, Daniel

458

Connecting the ear to the brain: Molecular mechanisms of auditory circuit assembly  

E-print Network

Connecting the ear to the brain: Molecular mechanisms of auditory circuit assembly Jessica M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 000 3.2.1. Sox2 and the maintenance of precursors in the inner ear 9 December 2010 Accepted 3 January 2011 Keywords: Auditory system Inner ear Neural development

Goodrich, Lisa V.

459

MicroRNAs are essential for development and function of inner ear hair cells in vertebrates  

E-print Network

MicroRNAs are essential for development and function of inner ear hair cells in vertebrates Lilach, the 2 inner ear compart- ments. A conditional knock-out mouse for Dicer1 demonstrated that miRNAs are crucial for postnatal survival of functional hair cells of the inner ear. We identified miRNAs that have

Hornstein, Eran

460

In Vivo Analysis of Lrig Genes Reveals Redundant and Independent Functions in the Inner Ear  

E-print Network

In Vivo Analysis of Lrig Genes Reveals Redundant and Independent Functions in the Inner Ear Tony compared the expression and function of the Lrigs in the inner ear, which offers a sensitive system in the inner ear throughout development, with Lrig1 and Lrig3 restricted to subsets of cells and Lrig2

Goodrich, Lisa V.

461

Vasopressin, ATP and Catecholamines Differentially Control Potassium Secretion in Inner Ear Cell line  

E-print Network

1 Vasopressin, ATP and Catecholamines Differentially Control Potassium Secretion in Inner Ear Cell (high potassium, low sodium fluid) and volume is instrumental for a proper functioning of the inner ear interesting perspectives for the management of inner ear diseases. Keywords: endolymph, vasopressin receptors

Paris-Sud XI, Université de

462

Identification with a recombinant antibody of an inner-ear cytokeratin, a marker for  

E-print Network

Identification with a recombinant antibody of an inner-ear cytokeratin, a marker for hair by A. James Hudspeth, February 4, 2000 Extensive biochemical characterization of cells in the inner ear has been hampered by a lack of tools with which to identify inner-ear proteins. By using a single

Hudspeth, A. James