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At least 1,099 records · Page 61Linked to original sources
PubMed2000

Supportive treatment in weight-losing cancer patients due to the additive adverse effects of radiation treatment and/or chemotherapy.

The reversal of anorexia and weight loss especially in patients with advanced cancer suffering from radiation treatment (RT) -related complications and debilitated furtherly during RT would be a welcome relief. The purpose of this study is to evaluate the feasibility of supportive treatment with megestrol acetate (MA) in our weight-losing cancer patients increasingly experiencing anorexia, smell, taste, and weight loss due to the additive adverse effects of RT +/- chemotherapy and how MA changes the additive role of the severity of RT reactions on such patients. From June 1997 to October 1998, 100 eligible patients were enrolled on a randomized, placebo-controlled clinical trial. Of the 100 patients, 46 received MA during RT and 4 after the end of the RT, and 50 received placebo for 3 months. Subjective parameters were assessed by a brief questionnaire form based on scoring from 1 to 5, according to the degree of the loss or change for each parameter of malnutrition, appetite, taste and smell developed by us. At the end of the study a statistically significant weight gain was achieved in the patient group receiving MA compared to the placebo group (+3 to +5 kg versus -3.7 to -5.9 kg, p=0.000). Significant improvements were seen in performance status (p=0.000), appetite (p=0.000), malnutrition (p=0.000), loss of taste (p=0.000) and smell qualities (p=0.02) in the MA group compared to the placebo group. In the MA group there was no statistically significant difference related to the weight changes according to the grade of either the acute or late RT effects (p=0.65 and 0.07, respectively). Whereas, in the placebo group a statistically significant additive effect of the acute and late RT effects was detected on weight loss (p=0.008 and 0.007, respectively). We observed no side-effects of MA in a 3-month time follow-up. The use of MA 480 mg/day during RT was effective in reversing anorexia and weight loss in spite of the acute RT effects, and helped most patients to well tolerate specific tumor therapy. Further evaluation of its mechanisms of action on RT-related adverse effects, tumor response relationships, and effect on patient survival are researched.

Anorexia↗
PubMedDate not supplied

[Computer modeling of mechanisms of the information processing in the olfactory bulb. II. Mechanisms of identification and short-term storage in the olfactory bulb: results of the computer experimentation].

The results of experimentation with the computer model of the olfactory bulb are presented. The architecture and scenario of the work of the model were described previously. The dynamic character of the identification process and the mechanism of memorizing short-term of smell stimuli are described. During the identification, a self-adjustment of the olfactory bulb to incoming signals occurs. The self-modification of mitral and tufted cell synapses enhances responses of the cells; upon subsequent presentation of the stimulus, the olfactory bulb responds with a higher activity. The modeling confirmed the validity of the assumption that the functions of mitral and tufted cells are to identify the components of a complex smell and the image of the smell as the whole.

Animals↗
PubMed2001

Effects of injury severity and cognitive exaggeration on olfactory deficits in head injury compensation claims.

The purpose of this study was to examine the relationship between exaggeration and scores on a test of olfactory discrimination in patients being assessed in connection with a claim for financial benefits. Participants were 448 patients referred to a private practice in Edmonton, Alberta, Canada for psychological or neuropsychological assessment, related to evaluation of impairment and disability resulting from a work-related or non-work related accident. All patients were involved in some form of compensation claim at the time of their evaluation. All patients completed two tests designed to detect exaggerated cognitive deficits, the Computerized Assessment of Response Bias (CARB) and the Word Memory Test (WMT) as part of their evaluation. The diagnostic groups included 322 head injury cases, varying from very minor to very severe. Normative data for the smell test were derived from 126 patients with orthopedic injuries who passed both the CARB and the WMT. Patients with more severe traumatic brain injuries were 10-12 times more likely to have olfactory deficits than persons with trivial to mild head injuries. In a subgroup of patients who failed either the CARB or the WMT, there was no relationship between injury severity and total scores on the smell test. Therefore, the dose-response relationship between brain injury severity and olfactory deficits is severely attenuated when patients who are probably exaggerating their cognitive deficits are included in the analyses. Those patients with trivial to mild head injuries who demonstrated adequate effort on both the CARB and the WMT were no more likely to show olfactory deficits than the non-head-injured orthopedic control subjects. Therefore, anosmia following mild traumatic brain injury should not be concluded from self-reports or from tests of smell unless tests of effort have been passed. Effort should also be controlled in group studies of olfaction.

Adult↗
PubMed1992

Acceptability trials with ready to eat foods in a rural area.

Acceptability trials with three types of recipes was carried out on 184 young preschoolers (6 months to 35 months) residing in four nearby villages around Hyderabad. Results of this study indicated that among the 3 types of supplementary foods (Sweet Ready Mix, Sweet Ready Mix with Amylase and Therapeutic food tested here, the Therapeutic food was more acceptable (taste, smell and bulk) to the children. The criteria for acceptability of the food was defined as the ability of 75% of the children to consume 75% or more of the food supplement at one sitting for 70% of the days of the trial. The Therapeutic food, a calorie dense supplement, met the above criteria. The acceptability was poor for the Sweet Ready Mix and Sweet Ready Mix with Amylase (< 4%) mainly due to quantity rather than taste and smell as revealed by the mothers. The mothers of the children also liked the taste and smell of the therapeutic food better. Consumption of the therapeutic food caused minimal side effects like diarrhea and vomiting when compared to side effects after eating Sweet Ready Mix and Sweet Ready Mix with Amylase in children.

Child, Preschool↗
PubMedDate not supplied

[Olfactory seizures and parasellar meningioma].

INTRODUCTION: Partial olfactory seizures are infrequent. They are related to the presence of lesions in the uncinate area of the temporal lobe. Patients describe smells during the ictal phase that are generally unpleasant. We report the cases of two patients with olfactory disorders of a paroxysmal nature caused by a parasellar meningioma. CASE REPORTS: Case 1: a 43 year old male who presented paroxysmal episodes in which he perceived a bitter smell, with dysphoria, linked to the presence of a left side parasellar meningioma. Case 2: a 45 year old female who presented paroxysmal episodes during which she could smell formaldehyde and this was linked to the presence of a left side parasellar meningioma. DISCUSSION: Olfactory seizures are related to structural alterations to the amygdala. The most frequent causes are associated to the presence of mesial temporal sclerosis and, above all, to tumours situated in the temporomesial structures that have diverse aetiologies.

Abdominal Pain↗
PubMed1990

[Solvents in drinking water from a thermostatic mixing battery].

In a hospital an odour of organic solvent could be smelled when a special thermostatic water mixer has been used. At no other water tap in the house a similar smell could be recognized. After stagnation overnight or after weekends the disgusting smell has been rather strong. The odour of organic solvent disappeared when the water had been running for some time. The organic compound in the drinking water has been identified and the thermostatic water mixer could be revealed as the source of the contamination. Further investigations of other thermostats showed a variety of alcoholic compounds which were used as thermostatic fluids.

Odorants↗
PubMed1989

Risk factors for oral cancer in women.

Interviews were obtained from 125 women with oral cavity cancer and 107 female controls to assess the role of mouthwash use as a risk factor for oral cancer in women. In addition to detailed information on mouthwash use throughout adult life, information was obtained regarding smoking, alcohol consumption, general oral hygiene practices, and occurrence of nonmalignant conditions of the oral cavity. Mouthwash use was not associated with increased oral cancer risk in terms of frequency, duration of use, dilution, or rinsing practices. Among mouthwash users, cases reported taking more mouthfuls of mouthwash at each use compared with controls. Again among mouthwash users, cases were significantly more likely than controls to give as a reason for using mouthwash "to disguise the smell of tobacco" and "to disguise the smell of alcohol," whereas similar proportions of cases and controls reported using mouthwash to "disguise the smell of onions, garlic, etc." and "to disguise breath odors due to mouth infections or dental problems." These first two reasons for using mouthwash were strongly associated with smoking and drinking, respectively, and appear to be proxies for these exposures. Smoking, drinking, having 10 or more missing teeth, and religious background (non-Jewish versus Jewish) were significantly associated with oral cancer.

Alcohol Drinking↗
PubMed1987

Dysosmia caused by encephalitis in a dog.

A 1- to 2-year-old Beagle was referred for evaluation of a disorder of the sense of smell. The dog had suddenly lost the ability to find rabbits, even though it previously had won field trials. Clinical findings indicated mild encephalitis with some capability to respond to odoriferous stimuli. An unusual test of the sense of smell is described; results indicated some sense of smell, although behavioral response to the odor was inappropriate. It was suspected that canine distemper encephalitis may have been associated with the dysosmia.

Animals↗
PubMed1997

Olfactory dysfunction in patients with head trauma.

BACKGROUND: The ability to smell is commonly altered by head trauma (HT). However, the nature, prevalence, prognosis, and etiology of such alterations are poorly understood. OBJECTIVES: To quantitatively determine the degree of olfactory function in patients with HT-related chemosensory complaints and to examine the influences of age, sex, HT severity, time since HT, and other variables on such function. Also, to use quantitative magnetic resonance imaging (MRI) to establish whether and to what degree damage to the olfactory bulbs and tracts, frontal lobes, and temporal lobes occurs. PATIENTS AND METHODS: Two hundred sixty-eight patients with HT from the University of Pennsylvania Smell and Taste Center, Philadelphia, were administered a quantitative odor identification test, a depression inventory, and a medical history questionnaire; 66 were retested after individual test-retest periods ranging from 1 month to 13 years. The volume of olfactory-related brain structures was determined in 15 patients and 15 controls using MRI. RESULTS: One hundred seventy-nine patients (66.8%) had anosmia, 55 (20.5%) had microsmia, and 34 (12.7%) had normosmia. Frontal impacts produced less dysfunction than back or side impacts. Of the 66 retested patients, 24 (36%) improved slightly, 30 (45%) had no change, and 12 (18%) worsened; only 3 patients, none of whom initially had anosmia, regained normal olfactory function. Trauma severity was related to olfactory test scores in patients with microsmia. Parosmia prevalence decreased from 41.1% to 15.4% over an 8-year posttrauma period. Olfactory bulb and tract volumes of male, but not female, patients with HT were greatly reduced relative to volumes of controls. CONCLUSIONS: Patients complaining of HT-related olfactory dysfunction typically have anosmia and rarely regain normal olfactory ability, parosmia prevalence decreases over time in such patients, and damage to olfaction-related brain structures can be observed in most such patients using an appropriate MRI protocol.

Adult↗
PubMed2006

Recovery of olfactory function following closed head injury or infections of the upper respiratory tract.

OBJECTIVE: To investigate the outcome of olfactory function in patients with olfactory loss following infections of the upper respiratory tract (post-URTI) or head trauma. DESIGN: Retrospective patient-based study. SETTING: Smell and Taste Outpatient Clinic at a university hospital. PATIENTS: A total of 361 patients (228 women, 133 men) were included. MAIN OUTCOME MEASURES: Olfactory function was assessed using the "Sniffin' Sticks" test battery, which result in a threshold, discrimination, and identification score. The mean interval between first and last visit was 14 months. RESULTS: In comparing the overall threshold, discrimination, and identification scores between the last and first visit, olfactory function improved in 26% of the patients whereas it decreased in 6%. The cause of olfactory impairment had a significant effect on the recovery rate of olfactory function. Within the post-URTI group (n = 262), 32% of the patients improved, but in the posttraumatic group (n = 99) only 10% improved. In patients with post-URTI olfactory loss, a negative correlation was found between age and recovery of olfactory function. In general, the factor "sex" had no significant effect on recovery of smell function. CONCLUSIONS: To our knowledge, the series of patients presented herein is the largest in the literature to date in which standardized testing methods were used to assess the progression of impaired olfaction. It showed that the rate of improvement of olfactory function was significantly higher in patients with post-URTI dysosmia compared with patients with posttraumatic dysosmia. During an observation period of approximately 1 year, more than 30% of patients with post-URTI olfactory loss experienced improvement, whereas only 10% of patients with posttraumatic olfactory loss experienced improvement. Furthermore, age plays a significant role in the recovery of olfactory function.

Adolescent↗
PubMed1986

Changes in olfactory acuity induced by total inferior turbinectomy.

The short-term and long-term effects of total inferior turbinectomy on smell acuity was assessed in two groups of patients. Olfactory thresholds were determined by a three-way forced-choice method, using four odorants. Resection of obstructive inferior turbinates resulted in a decrease in olfactory thresholds in 22 of 24 tested patients. No deleterious effect on smell acuity was observed in 16 patients tested 2 1/2 years or more after surgery. Subjective assessment of olfactory acuity is unreliable. It is our intention to focus attention on an aspect of intranasal surgery not frequently reported.

Adolescent↗
PubMed2004

Convergence of sensory systems in the orbitofrontal cortex in primates and brain design for emotion.

In primates, stimuli to sensory systems influence motivational and emotional behavior via neural relays to the orbitofrontal cortex. This article reviews studies on the effects of stimuli from multiple sensory modalities on the brain of humans and some other higher primates. The primate orbitofrontal cortex contains the secondary taste cortex, in which the reward value of taste is represented. It also contains the secondary and tertiary olfactory cortical areas, in which information about the identity and also about the reward value of odors is represented. A somatosensory input is revealed by neurons that respond to the viscosity of food in the mouth, to the texture (mouth feel) of fat in the mouth, and to the temperature of liquids placed into the mouth. The orbitofrontal cortex also receives information about the sight of objects from the temporal lobe cortical visual areas. Information about each of these modalities is represented separately by different neurons, but in addition, other neurons show convergence between different types of sensory input. This convergence occurs by associative learning between the visual or olfactory input and the taste. In that emotions can be defined as states elicited by reinforcers, the neurons that respond to primary reinforcers (such as taste and touch), as well as learn associations to visual and olfactory stimuli that become secondary reinforcers, provide a basis for understanding the functions of the orbitofrontal cortex in emotion. In complementary neuroimaging studies in humans, it is being found that areas of the orbitofrontal cortex are activated by pleasant touch, by painful touch, by taste, by smell, and by more abstract reinforcers such as winning or losing money. Damage to the orbitofrontal cortex in humans can impair the learning and reversal of stimulus-reinforcement associations and thus the correction of behavioral responses when these are no longer appropriate because previous reinforcement contingencies change. It is striking that humans and other catarrhines, being visual specialists like other anthropoids, interface the visual system to other sensory systems (e.g., taste and smell) in the orbitofrontal cortex.

Afferent Pathways↗
PubMed2002

Adult-like complexity of the larval antennal lobe of D. melanogaster despite markedly low numbers of odorant receptor neurons.

We provide a detailed analysis of the larval head chemosensory system of Drosophila melanogaster, based on confocal microscopy of cell-specific reporter gene expression in P[GAL4] enhancer trap lines. In particular, we describe the neuronal composition of three external and three pharyngeal chemosensory organs, the nerve tracts chosen by their afferents, and their central target regions. With a total of 21 olfactory and 80 gustatory neurons, the sensory level is numerically much simpler than that of the adult. Moreover, its design is different than in the adult, showing an association between smell and taste sensilla. In contrast, the first-order relay of the olfactory afferents, the larval antennal lobe (LAL), exhibits adult-like features both in terms of structure and cell number. It shows a division into approximately 30 subunits, reminiscent of glomeruli in the adult antennal lobe. Taken together, the design of the larval chemosensory system is a "hybrid," with larval-specific features in the periphery and central characteristics in common with the adult. The largely reduced numbers of afferents and the similar architecture of the LAL and the adult antennal lobe, render the larval chemosensory system of Drosophila a valuable model system, both for studying smell and taste and for examining the development of its adult organization.

Animal Structures↗
PubMed2001

Olfactory identification is impaired in clinic-based patients with vascular dementia and senile dementia of Alzheimer type.

AIMS: It is now well established that there are abnormalities in the sense of smell in patients suffering from Alzheimer's disease (AD). They have both raised olfactory thresholds and impaired odour identification. The situation in vascular dementia is unclear. We used the University of Pennsylvania Smell Identification Test (UPSIT), a 40-item, forced choice, cued, 'scratch-and- sniff' test, to examine olfactory identification in vascular dementia and to determine whether it would differentiate the disorder from AD and normal elderly. METHODS: We investigated three matched subject groups: 13 people having a Cambridge Examination for Mental Disorders in the Elderly (CAMDEX) diagnosis of definite senile dementia of Alzheimer type, 13 having a CAMDEX diagnosis of definite vascular dementia and 13 non-cognitively impaired controls. The subjects were then tested with the UPSIT in their own home by an independent blind researcher to see if the test could distinguish the different diagnostic groups in this setting. RESULTS: The median UPSIT score was 30 (out of a maximum of 40) for controls, 12 for the vascular group and 15 for the AD group. The difference was significant (p = 0.05) between both demented groups and the normal controls. Similarly there was a significant difference in the UPSIT score between the AD group and controls (p = 0.001) and between the vascular dementia group and controls (p = 0.001), but there was no significant difference between the AD group and the vascular dementia group. The UPSIT score correlated strongly with the degree of cognitive impairment as measured by the CAMCOG (r(s) = 0.683, p = 0.01) CONCLUSIONS: Patients with vascular dementia had a similar degree of olfactory impairment to those with AD. The UPSIT successfully differentiated between dementia patients and normal elderly British subjects tested in their own homes. The UPSIT did not differentiate between those with AD and vascular dementia.

Aged↗
PubMed2002

Odorant differentiated pattern of cerebral activation: comparison of acetone and vanillin.

Whether different odorous compounds (odorants) are processed by different cerebral circuits is presently unknown. A first step to address this complicated issue is to investigate how the cerebral regions mediating signals from olfactory (i.e., unimodal) odorants, differ from those mediating the olfactory + trigeminal (i.e., bimodal) odorants. [15O]-H2O-PET scans were conducted in 12 healthy females during three separate conditions: birhinal, passive smelling of: 1) the unimodal odorant vanillin; 2) the bimodal odorant acetone; and 3) odorless air. Significant activations were calculated contrasting vanillin to air, acetone to air, and deactivations, running these contrasts in the opposite direction. Smelling of vanillin activated bilaterally the amygdala and piriform cortex. These regions were only engaged slightly by acetone. Instead, strong activations were found in the anterior and central insula and claustrum, the posterior portion of anterior cingulate, the somatosensory cortex (SI for face), cerebellum, ventral medial (VMPo) and dorsal medial (MDvc) thalamus, the lateral hypothalamus, and pons/medulla. In parallel, the somatosensory (SI, below central representation of face), secondary visual and auditory cortices, as well as the supplementary motor area and the parahippocampal gyri were deactivated. No deactivations were observed with vanillin, although the odor components of acetone and vanillin were rated similarly intense (75 +/- 17 mm vs. 61 +/- 22 mm, NS). The differentiated pattern of cerebral activation during odorant perception seems to be dependent on the signal transducing cranial nerves involved. In contrast to vanillin, which solely activates the olfactory cortex, acetone engages predominantly trigeminal projections from the nasal mucosa. Acetone's limited activation of the olfactory cortex may result from a cross-modal interaction, with inhibition of acetone's odor component by its trigeminal component.

Acetone↗
PubMed1995

A possible protocognitive role for odor in human infant development.

Concepts relating to semiochemistry are now prevalent in the current literature on olfaction. Two fundamental tools of semiotics are metaphors, involving cognitive and verbal processes, and metonyms, involving nonverbal associations. By extending the concept of metonymy to non-linguistic transmission, we propose a possible explanation of how olfaction acts as a semiotic sense. Consideration of the sense of smell in animals and humans demonstrates its excellence for the formation of learned associations. In animals we find salient and complex information transmitted via biological odors. In this review, the olfactory dyadic relationship between mother and child is used for the theoretical proposal that the sense of smell plays an important protocognitive role in the genesis of cognition via mechanisms of in utero and postnatal nonlinguistic metonymic learning processes.

Brain↗
PubMed1998

Olfactory disorder in motor neuron disease.

In Parkinson's disease and Alzheimer's disease there is profound disorder of olfaction. The extent to which this modality is involved in motor neuron disease (MND) has been studied little. To address this further we assessed olfaction by three methods-a smell identification test ("UPSIT") in 58 patients and 135 controls; olfactory-evoked response (OEP) to H2S in 15 patients, and pathological examination of olfactory bulbs obtained from 8 cadavers. It was found that smell identification compared with the controls was slightly worse overall in the MND group as a whole, but only the bulbar patients scored significantly less on the UPSIT. Patients displayed a subtle defect in cheese odor recognition. OEPs were normal in 9 subjects and delayed in 1 subject. The remaining 5 OEPs were unsuccessful. Histopathological studies of olfactory bulbs showed excess lipofuscin deposition in all 8 cases examined, indicating subclinical neuronal damage. Olfactory neurons with a degree of antioxidant defect may be more susceptible to cellular damage than other neuronal groups because of their direct relationship to environmental agents. Overall we found the degree of olfactory dysfunction in MND to be mild and in contrast with the marked changes described by others.

Adolescent↗
PubMed1992

Differential olfactory perception of enantiomeric compounds by blind subterranean mole rats (Spalax ehrenbergi).

The behavior of mole rats (Spalax ehrenbergi) near pairs of enantiomeric compounds was examined in 901 two-choice experimental tests. Positioning of the nest and food store and the preferred location of the tested animal were used to assess attraction or aversion to the tested odorants. The results indicated that mole rats respond differentially to odors of stereoisomers (enantiomers of carvone, citronellol, and fechone). They responded to one enantiomer of each tested pair but were indifferent to or did not smell the other. Both sexes were attracted to the odor of R-(-)-carvone and repelled by the odor of (+)-citronellol. Females were attracted to the odor of (-)-fenchone while males had no preference. By contrast, all animals were indifferent to or did not smell the odor of S-(+)-carvone, (-)-citronellol, and (+)-fenchone. Further research to distinguish between these alternatives (indifference vs hyposmia/anosmia) is suggested.

Acyclic Monoterpenes↗