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1.
PLoS One ; 15(1): e0223034, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31990947

RESUMO

The ability to modify behavior based on prior experience is essential to an animal's survival. For example, animals may become attracted to a previously neutral odor or reject a previously appetitive food source based on previous encounters. In Drosophila, the mushroom bodies (MBs) are critical for olfactory associative learning and conditioned taste aversion, but how the output of the MBs affects specific behavioral responses is unresolved. In conditioned taste aversion, Drosophila shows a specific behavioral change upon learning: proboscis extension to sugar is reduced after a sugar stimulus is paired with an aversive stimulus. While studies have identified MB output neurons (MBONs) that drive approach or avoidance behavior, whether the same MBONs impact innate proboscis extension behavior is unknown. Here, we tested the role of MB pathways in altering proboscis extension and identified MBONs that synapse onto multiple MB compartments that upon activation significantly decreased proboscis extension to sugar. Activating several of these lines also decreased sugar consumption, revealing that these MBONs have a general role in modifying feeding behavior beyond proboscis extension. The MBONs that decreased proboscis extension and ingestion are different from those that drive avoidance behavior in another context. These studies provide insight into how activation of MB output neurons decreases proboscis extension to taste compounds.


Assuntos
Aprendizagem da Esquiva/fisiologia , Corpos Pedunculados/fisiologia , Neurônios/metabolismo , Sacarose/metabolismo , Animais , Comportamento Apetitivo/fisiologia , Dendritos/fisiologia , Drosophila/fisiologia , Luz , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Odorantes/análise , Olfato/fisiologia , Paladar/fisiologia
2.
PLoS One ; 15(1): e0217665, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923248

RESUMO

Olfactory sense remains elusive regarding the primary reception mechanism. Some studies suggest that olfaction is a spectral sense, the olfactory event is triggered by electron transfer (ET) across the odorants at the active sites of odorant receptors (ORs). Herein we present a Donor-Bridge-Acceptor model, proposing that the ET process can be viewed as an electron hopping from the donor molecule to the odorant molecule (Bridge), then hopping off to the acceptor molecule, making the electronic state of the odorant molecule change along with vibrations (vibronic transition). The odorant specific parameter, Huang-Rhys factor can be derived from ab initio calculations, which make the simulation of ET spectra achievable. In this study, we revealed that the emission spectra (after Gaussian convolution) can be acted as odor characteristic spectra. Using the emission spectrum of ET, we were able to reasonably interpret the similar bitter-almond odors among hydrogen cyanide, benzaldehyde and nitrobenzene. In terms of isotope effects, we succeeded in explaining why subjects can easily distinguish cyclopentadecanone from its fully deuterated analogue cyclopentadecanone-d28 but not distinguishing acetophenone from acetophenone-d8.


Assuntos
Percepção Olfatória/genética , Neurônios Receptores Olfatórios/metabolismo , Receptores Odorantes/genética , Olfato/genética , Benzaldeídos/farmacologia , Respiração Celular/genética , Transporte de Elétrons/genética , Humanos , Cianeto de Hidrogênio/farmacologia , Isótopos/farmacologia , Nitrobenzenos/farmacologia , Odorantes/análise , Percepção Olfatória/fisiologia , Neurônios Receptores Olfatórios/química , Receptores Odorantes/metabolismo , Olfato/fisiologia , Vibração
3.
Arch Insect Biochem Physiol ; 103(1): e21620, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31625196

RESUMO

Olfactory sensing and its modulation are important for the insects in recognizing diverse odors from the environment and in making correct decisions to survive. Identifying new genes involved in olfactory modulation and unveiling their mechanisms may lead us to understand decision making processes in the central nervous system. Here, we report a novel olfactory function of the cyclic nucleotide-gated (CNG) channel CG42260 in modulating ab3A olfactory sensory neurons, which specifically respond to food-derived odors in fruit fly Drosophila melanogaster. We found that two independent CG42260 mutants show reduced responses in the ab3A neurons. Unlike mammalian CNGs, CG42260 is not expressed in the odorant sensory neurons but broadly in the central nervous system including neuropeptide-producing cells. By using molecular genetic tools, we identified CG42260 expression in one pair of neuropeptide F (NPF) positive L1-l cells known to modulate food odor responsiveness. Knockdown of CG42260 in the NPF neurons reduced production of NPF in Ll-1 cells, which in turn, led to reduction of neuronal responses of the ab3A neurons. Our findings show the novel biological function of CG42260 in modulating olfactory responses to food odor through NPF.


Assuntos
Canais de Cátion Regulados por Nucleotídeos Cíclicos/metabolismo , Drosophila melanogaster/fisiologia , Neuropeptídeos/metabolismo , Neurônios Receptores Olfatórios/metabolismo , Animais , Encéfalo/metabolismo , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Fenômenos Eletrofisiológicos , Mutagênese Insercional , Neuropeptídeos/genética , Odorantes , Olfato/fisiologia
4.
Urologiia ; (5): 22-26, 2019 Dec.
Artigo em Russo | MEDLINE | ID: mdl-31808627

RESUMO

INTRODUCTION: A screening of prostate cancer is an important problem of healthcare system worldwide. AIM: To evaluate a possibility and efficiency of Belgian Malinois dogs sense of smell in diagnosis of prostate cancer. MATERIALS AND METHODS: Urine samples from 176 men were assessed. Of these, 112 samples were taken from patients with biopsy-proven prostate cancer, and 64 from healthy young men. The study with two Belgian Malinois dogs consisted of two stages. The first stage was to train the dogs to distinguish the urine of patients with prostate cancer. A total of 66 urine samples were used at this stage (from 42 patients with prostate cancer and 24 healthy people). At the second detection stage, urine samples of patients with prostate cancer was identified. A total of 110 urine samples were evaluated (70 patients with prostate cancer and 40 healthy people). RESULTS: The first dog correctly identified 68 samples from patients with prostate cancer, and in 37 cases it indicated the absence of disease (sensitivity 97.1%, specificity 92.5%, accuracy 95.4%). The second animal correctly identified 69 and 39 samples, respectively (sensitivity 98.6%, specificity 97.5%, accuracy 98.2%). CONCLUSION: A possibility of training dogs to identify patients with prostate cancer has been demonstrated. Further studies dedicated to the detection of volatile organic compounds in the urine using specialized analyzers of "electronic nose" type, as well as gas chromatography in combination with mass spectrometry, are of both scientific and practical interest.


Assuntos
Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/urina , Olfato/fisiologia , Compostos Orgânicos Voláteis/urina , Animais , Cães , Humanos , Masculino , Programas de Rastreamento , Sensibilidade e Especificidade
5.
Behav Processes ; 169: 103989, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31669749

RESUMO

Foraging trails of leaf-cutting ants may be exposed to plant material that interferes with foragers' flux either by physically blocking it or due to secondary metabolites which affect insect behavior. We hypothesized that plant secondary metabolites such as plant volatiles may interfere with pheromone communication, triggering clearing behavior. We impregnated small pieces of paper with different plant odors from native and exotic species and placed them in the middle of foraging trails of the leaf-cutting ant Acromyrmex lobicornis. As a control, we used papers impregnated with trail odor. The paper used as substrate for the odors did not constitute a physical obstacle based on its small surface area. Papers treated with trail odor did not interfere with ant flux and were not removed from the trail. However, when papers were treated with plant odors, they were removed from the trail in most of the cases and ant flux was reduced significantly by 15-28%. We found that ants tapped the tip of their gaster against the ground around the treated papers only when they were impregnated with foreign odors. The number of gaster tappings as well as the time between the placement of the paper and its removal increased with plant odor concentration. However, the decision to remove the paper was not correlated with the number of gaster tappings. Interestingly, clearer ants were smaller than forager ants, suggesting there is morphological differentiation in clearing behavior of the trail. Results from the current study also suggest that odors trigger clearing behavior on foraging trails and affect trail marking behavior. Our results provide information about the potential for plant compounds to constitute obstacles, even when they do not physically obstruct the trail. We conclude that odors may trigger clearing behavior by interfering with pheromone communication.


Assuntos
Formigas/fisiologia , Comportamento Animal/fisiologia , Comportamento Alimentar/fisiologia , Odorantes , Olfato/fisiologia , Animais , Feromônios , Plantas
6.
J Laryngol Otol ; 133(12): 1046-1049, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31679530

RESUMO

OBJECTIVE: There are few detailed studies about peripheral branch resection of the posterior nasal nerves in the inferior turbinate; thus, this study aimed to investigate this. METHODS: Patients who underwent submucosal turbinoplasty with or without resection of the peripheral branches of posterior nasal nerves in the inferior turbinate were included. RESULTS: The resection of the posterior nasal nerves with turbinoplasty significantly reduced detection and recognition thresholds on olfactory testing. The rhinorrhoea severity, detection threshold and recognition threshold were significantly lower after resection of the posterior nasal nerves with turbinoplasty than after turbinoplasty alone, although there were no significant differences between the two groups before surgery. CONCLUSION: This is the first study to show that the resection of the peripheral branches of the posterior nasal nerves in the inferior turbinate with turbinoplasty more effectively inhibits allergic symptoms compared with turbinoplasty alone. It also showed that the resection of the peripheral branches of the posterior nasal nerves can inhibit olfactory dysfunction.


Assuntos
Transtornos do Olfato/cirurgia , Conchas Nasais/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos do Olfato/diagnóstico , Transtornos do Olfato/etiologia , Rinite Alérgica/complicações , Rinite Alérgica/cirurgia , Olfato/fisiologia , Resultado do Tratamento , Conchas Nasais/inervação , Adulto Jovem
8.
Forensic Sci Int ; 303: 109953, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31546168

RESUMO

Ignitable liquid detection dogs have been observed to falsely-respond to the pyrolysis products of common burned household items such as carpets and garden hoses, where ignitable liquids were not present. These responses from the canines are described as coming from distractor odours and decrease the reliability of detector dogs. The purpose of this research was to study the volatile organic compounds (VOCs) present in the odour profile of pyrolysed carpet and garden hose substrates, and determine whether a chemical similarity exists between these pyrolysis headspace profiles and target ignitable liquids, which may explain the false-positive behaviour of these detector dogs. Garden hose and carpet samples obtained from domestic settings were heated at a constant temperature for a specified time to produce pyrolysis products. A solid-phase microextraction (SPME) method was developed to extract the VOCs from burned substrates. The odours of the burned substrates were analysed by gas chromatography-mass spectrometry (GC/MS) and gas chromatography-tandem mass spectrometry (GC/MS/MS). A GC-MS/MS method was developed targeting the characteristic aromatic compounds in gasoline. Each pyrolysed substrate produced a complex and unresolved odour profile when analysed by GC- MS. GC-MS analysis failed to find any similarities between the odours of the burned substrates and ignitable liquids. GC-MS/MS analysis of pyrolysed garden hose and carpet substrate odours resolved and identified a wide range of aromatic target compounds - and these were present in high abundances in the hose samples. This indicates that there are significant chemical similarities between vapours of ignitable liquids and their distractor odours, which will have implications for the training of ignitable liquid detector dogs.


Assuntos
Cães/fisiologia , Fogo , Odorantes , Olfato/fisiologia , Compostos Orgânicos Voláteis/análise , Animais , Ciências Forenses , Cromatografia Gasosa-Espectrometria de Massas
9.
Eur Arch Otorhinolaryngol ; 276(12): 3367-3372, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31473779

RESUMO

OBJECTIVE: The aim of this study was to investigate the effect of the medical and the surgical treatment on the olfactory functions, clinical scoring systems and inflammation markers in patients with nasal polyposis. In addition, the secondary aim was to investigate the correlation between those investigated parameters. SUBJECTS AND METHODS: A total of 30 patients, who completed the standardized medical and surgical treatment and also came to 3 months of follow-ups regularly after the surgery, were included in the study. The Sniffin' Sticks olfactory tests, radiological and the endoscopic stagings, liver-expressed chemokine (CCL16) and endothelin (ET) levels and sino-nasal outcome test-22 (SNOT-22) were performed at the initial and at the end of the study. RESULTS: The current study had four major findings: (1) significant improvement in odor functions after treatment was determined; however, the majority of the patients had been already hyposmic. (2) In addition, significant improvement was found in ET and CCL16 levels, SNOT-22 results, and radiologic and endoscopic stagings at the end of the study. (3) However, there was no correlation between the olfactory functions and the investigated parameters. (4) There was a positive correlation between polyp recurrence and ET levels. CONCLUSION: The standardized medical and surgical treatment provided a significant improvement in the olfactory functions. However, only one patient (3.3%) had become normosmic at the end of the study.


Assuntos
Quimiocinas CC/sangue , Endoscopia/métodos , Endotelinas/sangue , Pólipos Nasais/tratamento farmacológico , Pólipos Nasais/cirurgia , Transtornos do Olfato/etiologia , Percepção Olfatória/fisiologia , Olfato/fisiologia , Adulto , Biomarcadores , Feminino , Seguimentos , Humanos , Inflamação/complicações , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/complicações , Transtornos do Olfato/fisiopatologia , Prednisolona/uso terapêutico , Estudos Prospectivos , Recuperação de Função Fisiológica , Limiar Sensorial/fisiologia , Resultado do Tratamento
10.
Med Sci Monit ; 25: 5929-5933, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31395849

RESUMO

BACKGROUND The objective of this study was to detect the level of olfactory function in patients with systemic lupus erythematosus (SLE) and to explore the relationship between impaired olfactory function and anti-ribosomal P protein antibody (ARPA), disease duration, and age. MATERIAL AND METHODS The level of olfactory function in 65 patients with SLE and 50 healthy participants was detected using the Connecticut Chemosensory Clinical Research Center (CCCRC) method; serum ARPA levels in SLE patients and the healthy control group were detected by enzyme-linked immunosorbent assay (ELISA). RESULTS CCCRC scores in the active SLE group was lower than that in the inactive SLE and healthy control groups (P<0.01). In SLE patients, the CCCRC scores of ARPA-positive patients were lower than those of ARPA-negative patients (P<0.01). A negative correlation was discovered between CCCRC scores and ARPA serum levels in SLE patients. Multiple linear regression analyses showed a correlation among the CCCRC score, age, and ARPA. CONCLUSIONS Olfactory dysfunction was found in patients with active SLE; which correlated with SLE disease activity and ARPA levels.


Assuntos
Lúpus Eritematoso Sistêmico/complicações , Percepção Olfatória/fisiologia , Olfato/fisiologia , Adolescente , Adulto , Fatores Etários , Idoso , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Lúpus Eritematoso Sistêmico/sangue , Lúpus Eritematoso Sistêmico/fisiopatologia , Masculino , Pessoa de Meia-Idade , Proteínas Ribossômicas/imunologia , Índice de Gravidade de Doença
11.
J Food Sci ; 84(9): 2666-2673, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31441517

RESUMO

Natural plant extracts are increasingly used as functional feed ingredients in animal husbandry and food ingredients in human alternative medicine to improve welfare and health. We investigated in 20 growing pigs via functional magnetic resonance imaging (fMRI) the brain blood oxygen level-dependent (BOLD) responses to olfactory stimulation with two sensory functional feed ingredients, A and B, at two different concentrations. Functional ingredient A contained extracts from Citrus sinensis (60% to 80%), and ingredient B contained a mixture of extracts Oreganum vulgarae (40% to 55%) and Cymbopogon flexuosus (20% to 25%). Increased concentration of ingredients induced a higher activation in reward and cognitive areas compared to lower concentrations. Moreover, considering both ingredients at the highest concentration, the ingredient A elicited higher brain responses in brain areas involved in hedonism/pleasantness compared to ingredient B, and more specifically in the caudate nucleus and orbitofrontal cortex. Our findings shed new light in the scope of emotion regulation through olfactory modulation via sensory functional ingredients, which opens the way to further preclinical studies in animal models and translational research in the context of nutrition, welfare, and health. PRACTICAL APPLICATION: Functional food/feed ingredients are gaining interest for improving health and welfare in humans and animals. Besides representing an alternative to antibiotics for example, food ingredients and their sensory characteristics might have a positive impact on emotions and consequently on well-being. Functional brain imaging in large animals such as in the pig model is a promising approach to investigate the central and behavioural effects of food ingredients, and determine the most effective blends and concentrations to modulate internal and emotional states.


Assuntos
Estimulantes do Apetite/farmacologia , Encéfalo , Imagem por Ressonância Magnética , Olfato , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Emoções/efeitos dos fármacos , Emoções/fisiologia , Ingredientes de Alimentos , Alimento Funcional , Extratos Vegetais , Olfato/efeitos dos fármacos , Olfato/fisiologia , Suínos
12.
Forensic Sci Int ; 302: 109895, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31419594

RESUMO

A scent lineup is generally a procedure whereby a dog's alerting behavior is used to establish that the dog detects two scents, one from a crime scene and one from a suspect, as deriving from the same person. The aim of this article is to compare methodologies of using dogs in scent lineups as a means of identifying perpetrators of crimes. It is hoped that this comparative approach, looking at countries where the method is currently or has in the past been used, will help determine what issues should be addressed in order to assure that the scent lineup will have a future as a forensic technique. Participants from eleven countries-Belgium, The Czech Republic, Finland, France, Germany, Hungary, Lithuania, The Netherlands, Poland, Russia, and the U.S.-completed a survey questionnaire regarding key aspects of the scent lineup procedures used by the police in their countries. Although there was broad overlap on certain matters, such as the use of control and zero trials, collection of decoy scents from individuals of similar gender and race as the suspect, materials for holding scent, frequency of cleaning and changing stations, and use and timing of rewards, there were significant differences in the degree of blindness required, who calls an alert (handler or experimenter), and whether handlers can work with more than one dog. The gap between recommendations and results available from the scientific literature and procedures used in police practice was greater for some countries than others, even taking into account that some scientific methodologies might be expensive or impractical given agency resources. The authors make recommendations about how to go forward if scent lineups are to remain a valid forensic technique.


Assuntos
Direito Penal , Cães/fisiologia , Odorantes , Olfato/fisiologia , Animais , Europa (Continente) , Federação Russa , Inquéritos e Questionários , Estados Unidos
13.
Forensic Sci Int ; 302: 109907, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31401415

RESUMO

In sexual assault cases, the detection and identification of semen is extremely important as this type of evidence can be used as a source for investigative leads and contributes to case evidence. However, the detection of semen stains is often difficult, even indoors, because of different (environmental) factors, such as substrate type, coloured items and large search areas. In 2015, a project was initiated by the Dutch police to evaluate the feasibility of the use of detection dogs to locate semen stains in forensic practise. Since promising results were obtained, here, a double-blind study was designed to investigate how these detection dogs can optimally be implemented in the current work flow of crime scene investigators and to compare the dog's sensitivity and specificity with current detection methods. The performance of the detection dogs was compared to three commonly used detection methods for semen, (i) forensic light sources (FLS), (ii) the RSID semen field kit and (iii) the enzymatic Acid Phosphatase (AP)-test on semen deposited at different types of fabrics. A 100% sensitivity and specificity for the detection of semen stains using the detection dogs was obtained, compared to an overall sensitivity and specificity of 76.3% and 100% for FLS, 81.6% and 100% for RSID-test, and 92.1% and 100% for AP-test, respectively. Especially, on fabrics with a pattern or interfering fluorescent properties, detection dogs demonstrated to be of additional value to locate the semen stains. We recommend to use the following order of testing, FLS, detection dog, AP-test and RSID test in a forensic workflow.


Assuntos
Cães/fisiologia , Medicina Legal/métodos , Odorantes , Sêmen , Olfato/fisiologia , Têxteis , Fosfatase Ácida/isolamento & purificação , Animais , Crime , Fluorescência , Humanos , Imunoensaio/métodos , Luz , Masculino , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade
14.
PLoS Biol ; 17(8): e3000400, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31454345

RESUMO

Adaptive decision-making depends on the formation of novel memories. In Drosophila, the mushroom body (MB) is the site of associative olfactory long-term memory (LTM) storage. However, due to the sparse and stochastic representation of olfactory information in Kenyon cells (KCs), genetic access to individual LTMs remains elusive. Here, we develop a cAMP response element (CRE)-activity-dependent memory engram label (CAMEL) tool that genetically tags KCs responding to the conditioned stimulus (CS). CAMEL activity depends on protein-synthesis-dependent aversive LTM conditioning and reflects the time course of CRE binding protein 2 (CREB2) activity during natural memory formation. We demonstrate that inhibition of LTM-induced CAMEL neurons reduces memory expression and that artificial optogenetic reactivation is sufficient to evoke aversive behavior phenocopying memory recall. Together, our data are consistent with CAMEL neurons marking a subset of engram KCs encoding individual memories. This study provides new insights into memory circuitry organization and an entry point towards cellular and molecular understanding of LTM storage.


Assuntos
Memória de Longo Prazo/fisiologia , Memória/fisiologia , Animais , Condicionamento Clássico , Condicionamento Operante , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Corpos Pedunculados/metabolismo , Corpos Pedunculados/fisiologia , Neurônios/fisiologia , Odorantes , Olfato/fisiologia
15.
Molecules ; 24(16)2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31426361

RESUMO

Key odorants of red wine made from the hybrid grapes of Marselan (Vitis vinifera L.) were isolated by solid-phase extraction (SPE) and explored by gas chromatography-olfactometry (GC-O) analysis. Application of aroma extract dilution analysis (AEDA) revealed 43 odor-active compounds, and 31 odorants among them were detected with flavor dilution (FD) factors ranging from 9 to 2187. Comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry (GC × GC-TOF-MS) were exploited to quantitate the aroma-active compounds with FD ≥9. The identification indicated ß-damascenone as having the highest FD factors, followed by eugenol, 2,3-butanedione, citronellol, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, phenethyl acetate, guaiacol, and 2-methoxy-4-vinylphenol. A total of 21 compounds were found to have odor activity values (OAVs) >1.0. Aroma reconstitution validation experiments showed a good similarity of blackberry, green pepper, honey, raspberry, caramel, smoky, and cinnamon aroma attributes between the original Marselan wine and the reconstructed wine. In addition, omission tests were carried out to further determine the contribution of odorants to the overall aroma.


Assuntos
Odorantes/análise , Olfato/fisiologia , Vitis/química , Compostos Orgânicos Voláteis/isolamento & purificação , Vinho/análise , /isolamento & purificação , Diacetil/isolamento & purificação , Eugenol/isolamento & purificação , Feminino , Furanos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Guaiacol/análogos & derivados , Guaiacol/isolamento & purificação , Humanos , Masculino , Norisoprenoides/isolamento & purificação , Olfatometria/instrumentação , Olfatometria/métodos , Extração em Fase Sólida/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Paladar/fisiologia , Compostos de Vinila/isolamento & purificação , Compostos Orgânicos Voláteis/classificação
16.
Eur Arch Otorhinolaryngol ; 276(12): 3359-3366, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31270597

RESUMO

PURPOSE: Anticipating the possibility of olfactory recovery after functional endoscopic surgery (FES) in nasal polyposis (NP) is difficult. The main objective of this study was to assess the predictive factors of recovering the sense of smell after radical bilateral ethmoidectomy. Secondary objectives were to identify other predictors of olfactory recovery. METHODS: Open prospective study was conducted at the Nantes University Hospital including all patients with NP operated on in the Ear, Nose, and Throat Department between January 2011 and September 2017. These patients underwent functional endoscopic surgery (radical ethmoidectomy) after medical treatment failure. Olfaction was quantified prospectively and systematically during the preoperative consultation using a visual analog scale. Multivariate analysis evaluated the presence of predictive factors of postoperative olfactory recovery. RESULTS: One hundred nineteen patients were included in the study. Overall, olfaction was partially improved after surgery. For patients who presented greater than 50% recovery of olfaction after systemic corticosteroid therapy before surgery, we observed a predictive better rate of olfactory recovery after surgery (p < 0.001). Age over 65 years, a history of sinonasal surgery, associated asthma, and bacterial colonization were not associated with less postoperative olfactory recovery. CONCLUSION: This study identified an objective factor that may influence olfactory recovery after FES using a therapeutic trial for olfactory recovery after oral corticosteroid treatment taken before surgery.


Assuntos
Corticosteroides/uso terapêutico , Endoscopia/métodos , Seio Etmoidal/cirurgia , Pólipos Nasais/cirurgia , Transtornos do Olfato/fisiopatologia , Olfato/efeitos dos fármacos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pólipos Nasais/complicações , Pólipos Nasais/fisiopatologia , Transtornos do Olfato/etiologia , Transtornos do Olfato/terapia , Procedimentos Cirúrgicos Otorrinolaringológicos/efeitos adversos , Procedimentos Cirúrgicos Otorrinolaringológicos/métodos , Medição da Dor , Período Pós-Operatório , Estudos Prospectivos , Recuperação de Função Fisiológica , Olfato/fisiologia , Resultado do Tratamento , Escala Visual Analógica
17.
PLoS Comput Biol ; 15(7): e1007188, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31323033

RESUMO

The olfactory system faces the difficult task of identifying an enormous variety of odors independent of their intensity. Primacy coding, where the odor identity is encoded by the receptor types that respond earliest, might provide a compact and informative representation that can be interpreted efficiently by the brain. In this paper, we analyze the information transmitted by a simple model of primacy coding using numerical simulations and statistical descriptions. We show that the encoded information depends strongly on the number of receptor types included in the primacy representation, but only weakly on the size of the receptor repertoire. The representation is independent of the odor intensity and the transmitted information is useful to perform typical olfactory tasks with close to experimentally measured performance. Interestingly, we find situations in which a smaller receptor repertoire is advantageous for discriminating odors. The model also suggests that overly sensitive receptor types could dominate the entire response and make the whole array useless, which allows us to predict how receptor arrays need to adapt to stay useful during environmental changes. Taken together, we show that primacy coding is more useful than simple binary and normalized coding, essentially because the sparsity of the odor representations is independent of the odor statistics, in contrast to the alternatives. Primacy coding thus provides an efficient odor representation that is independent of the odor intensity and might thus help to identify odors in the olfactory cortex.


Assuntos
Modelos Neurológicos , Odorantes , Percepção Olfatória/fisiologia , Receptores Odorantes/fisiologia , Olfato/fisiologia , Animais , Biologia Computacional , Simulação por Computador , Humanos , Bulbo Olfatório/fisiologia , Condutos Olfatórios/fisiologia , Neurônios Receptores Olfatórios/fisiologia
18.
Am J Otolaryngol ; 40(5): 747-754, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31345588

RESUMO

OBJECTIVE: Patients with septal deviation-induced nasal obstruction may experience olfactory impairment. This study aimed to evaluate septoplasty-related changes in olfactory function and their effect on patients' quality of life (QoL). METHODS: Prospective study of sixty patients with nasal obstruction and septal deviation and 25 healthy controls. Objective measurements were performed for the evaluation of nasal patency and "Sniffin' sticks" tests were used for quantitative assessment of lateralized and bilateral olfactory performance. All participants self-assessed their smell using a visual analog scale and completed validated questionnaires for nasal obstruction (Nasal Obstruction Symptom Evaluation: NOSE), for nasal symptoms QoL (SinoNasal Outcome Test-22: SNOT-22), for olfaction-associated QoL (Questionnaire of Olfactory Deficits: QOD) preoperatively and six months after septoplasty and reported personal benefit after surgery (Glasgow Benefit Inventory: GBI), six months postoperatively. RESULTS: Smell was significantly compromised due to septal deviation especially in the more obstructed nasal cavity side. Smell improved significantly after septoplasty (subjective report and olfactory measurements), along with increased nasal patency. Increased nasal cavity volume was significantly correlated with olfactory thresholds but not with suprathreshold measurements. Subjective hyposmia and lateralized olfaction were significantly reduced postoperatively. Postoperatively, normosmic patients reported higher personal benefit from surgery than patients with olfactory disorders. The patients' QoL improved significantly, but it remained lower than the controls' group. Olfaction-associated QoL was not significantly different between patients and controls before and after septoplasty. CONCLUSION: Septoplasty leads to improvement in smell perception, and patients with improved smell report greater personal benefit from septoplasty than patients with remaining olfactory deficits.


Assuntos
Obstrução Nasal/cirurgia , Septo Nasal/cirurgia , Transtornos do Olfato/diagnóstico , Qualidade de Vida , Olfato/fisiologia , Adulto , Estudos de Coortes , Feminino , Seguimentos , Grécia , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução Nasal/complicações , Obstrução Nasal/diagnóstico por imagem , Septo Nasal/fisiopatologia , Transtornos do Olfato/etiologia , Estudos Prospectivos , Recuperação de Função Fisiológica , Rinoplastia/métodos , Medição de Risco , Estatísticas não Paramétricas , Resultado do Tratamento , Adulto Jovem
19.
Nat Neurosci ; 22(8): 1306-1317, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31332371

RESUMO

The elementary stimulus features encoded by the olfactory system remain poorly understood. We examined the relationship between 1,666 physical-chemical descriptors of odors and the activity of olfactory bulb inputs and outputs in awake mice. Glomerular and mitral and tufted cell responses were sparse and locally heterogeneous, with only a weak dependence of their positions on physical-chemical properties. Odor features represented by ensembles of mitral and tufted cells were overlapping but distinct from those represented in glomeruli, which is consistent with an extensive interplay between feedforward and feedback inputs to the bulb. This reformatting was well described as a rotation in odor space. The physical-chemical descriptors accounted for a small fraction in response variance, and the similarity of odors in the physical-chemical space was a poor predictor of similarity in neuronal representations. Our results suggest that commonly used physical-chemical properties are not systematically represented in bulbar activity and encourage further searches for better descriptors of odor space.


Assuntos
Odorantes , Bulbo Olfatório/fisiologia , Olfato/fisiologia , Animais , Retroalimentação Fisiológica , Feminino , Masculino , Camundongos , Bulbo Olfatório/diagnóstico por imagem , Condutos Olfatórios , Células Receptoras Sensoriais/fisiologia
20.
Cochrane Database Syst Rev ; 7: CD013038, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31311064

RESUMO

BACKGROUND: Preterm infants are often unable to co-ordinate sucking, swallowing and breathing for oral feeding because of their immaturity; in such cases, initial nutrition is provided by orogastric or nasogastric tube feeding. Feed intolerance is common and can delay attainment of full enteral feeds and sucking feeds, which prolongs the need for intravenous nutrition and hospital stay. Smell and taste play an important role in the activation of physiological pre-absorptive processes that contribute to food digestion and absorption. However, during tube feedings, milk bypasses the nasal and oral cavities, which limits exposure to the smell and taste of milk. Provision of the smell and taste of milk with tube feedings is non-invasive and inexpensive; and if it does accelerate the transition to enteral feeds, and then to sucking feeds, it would be of considerable potential benefit to infants, their families, and the healthcare system. OBJECTIVES: To assess whether exposure to the smell or taste (or both) of milk administered with tube feedings can accelerate progress to full sucking feeds without adverse effects in preterm infants. SEARCH METHODS: We used the standard search strategy of Cochrane Neonatal to search the Cochrane Central Register of Controlled Trials (CENTRAL 2018, Issue 5), MEDLINE via PubMed (1966 to 1 June 2018), Embase (1980 to 1 June 2018), and CINAHL (1982 to 1 June 2018). We also searched clinical trials databases, conference proceedings, and the reference lists of retrieved articles for randomised and quasi-randomised trials. SELECTION CRITERIA: We included randomised and quasi-randomised studies that compared the provision of the smell or taste of milk (or both) immediately before or at the time of tube feedings, with no provision of smell or taste. DATA COLLECTION AND ANALYSIS: Two review authors independently abstracted data according to Cochrane Neonatal methodology; they also assessed risk of bias, and the quality of evidence at the outcome level using the GRADE approach. We performed meta-analyses using risk ratio (RR) for dichotomous data and mean difference (MD) for continuous data, with their respective 95% confidence intervals (CIs). MAIN RESULTS: Three trials involving a total of 161 preterm infants were included in this review, but only two trials (131 infants) contributed data for meta-analysis. There was no evidence of a clear effect of exposure to the smell and taste of milk with tube feedings on time taken to reach full sucking feeds (MD -2.57 days, 95% CI -5.15 to 0.02; I2 = 17%; 2 trials, 131 infants; very low-quality evidence). One trial reported no adverse effects. There was no evidence of a clear effect of exposure to the smell and taste of milk on the following outcomes: time taken to reach full enteral feeds (MD -1.57 days, 95% CI -6.25 to 3.11; 1 trial, 51 infants; very low-quality evidence), duration of parenteral nutrition (MD -2.20 days, 95% CI -9.49 to 5.09; 1 trial, 51 infants; very low-quality evidence), incidence of necrotising enterocolitis (RR 0.62, 95% CI 0.15 to 2.48; 1 trial, 51 infants; low-quality evidence), and late infection (RR 2.46, 95% CI 0.27 to 22.13; 1 trial, 51 infants; low-quality evidence). There was very low-quality evidence demonstrating that exposure to the smell and taste of milk decreased duration of hospitalisation by almost four days (MD -3.89 days, 95% CI -7.03 to -0.75; I2 = 51%; 2 trials, 131 infants). In two trials, an increased growth velocity was noted in infants exposed to the intervention, but we were unable to combine data to perform meta-analysis. No data were available to assess feed intolerance and rates of exclusive breastfeeding at discharge. Included trials were small and had methodological limitations including lack of randomisation (one trial), lack of blinding, and different inclusion criteria and administration of the interventions. AUTHORS' CONCLUSIONS: Evidence from two trials suggests that exposure to the smell and taste of milk with tube feedings has no clear effect on time taken to reach full sucking feeds, but it may decrease length of hospitalisation. However, these results are uncertain due to the very low quality of the evidence. There is also limited evidence about the impact on other important clinical outcomes and on safety. Future research should examine the effect of exposure to the smell and taste of milk with tube feedings on clinical outcomes during hospitalisation, such as attainment of full enteral and sucking feeds, safety, feed tolerance, incidence of infection, and infant growth. Additionally, future research should be sufficiently powered to evaluate the effect of the intervention in infants of different gestational ages, on each sex separately, and on the optimal frequency and duration of exposure.


Assuntos
Recém-Nascido Prematuro/crescimento & desenvolvimento , Intubação Gastrointestinal , Olfato , Paladar , Humanos , Fenômenos Fisiológicos da Nutrição do Lactente , Recém-Nascido , Recém-Nascido Prematuro/fisiologia , Intubação Gastrointestinal/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Olfato/fisiologia , Comportamento de Sucção , Paladar/fisiologia , Ganho de Peso
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