Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “MOUTH”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 631 records · Page 35Linked to original sources
PubMed1994

Advancement cheiloplasty for reconstruction of floor of mouth defects.

In many cases of carcinoma of the floor of mouth, oncologic resection includes marginal mandibulectomy. Reconstruction poses a significant challenge. Requirements include coverage with thin but supple tissue to allow for dental implant or denture, and recreation of a mobile tongue and sensate floor of mouth gutter. Reconstructive efforts have ranged from skin grafts to free flaps, with variable success in fulfilling the above-mentioned requirements. This paper describes the preferred technique of the author, in which external mandibular periosteum is saved and elevated with a submucosal flap of lower lip, raised to the level of the vermilion border. This flap is then advanced to ventral tongue. In this manner the entire anterior floor of mouth can be reconstructed. Cases are presented demonstrating different aspects to the technique.

Adult↗
PubMed1995

Dramatic differences in the motions of the mouth of open and closed cytochrome P450BM-3 by molecular dynamics simulations.

Molecular dynamics trajectories were calculated separately for each of the two molecules in the asymmetric unit of the crystal structure of the hemoprotein domain of cytochrome P450BM-3. Each simulation was 200 ps in length and included a 10 A layer of explicit solvent. The simulated time-average structure of each P450BM-3 molecule is closer to its crystal structure than the two molecular dynamics time-averaged structures are to each other. In the crystal structure, molecule 2 has a more accessible substrate binding pocket than molecule 1, and this difference is maintained throughout the simulations presented here. In particular, the substrate docking regions of molecule 1 and molecule 2 diverge in the solution state simulations. The mouth of the substrate binding pocket is significantly more mobile in the simulation of molecule 2 than in the simulation of molecule 1. For molecule 1, the width of the mouth is only slightly larger than its X-ray value of 8.7 A and undergoes fluctuations of about 1 A. However, in molecule 2, the mouth of the substrate binding pocket is dramatically more open in the time-average molecular dynamics structure (14.7 A) than in the X-ray structure (10.9 A). Furthermore, this region of the protein undergoes large amplitude motions during the trajectory that are not seen in the trajectory of molecule 1, repeatedly opening and closing up to 7 A. Presumably, the binding of different substrates will induce the mouth region to adopt different conformations from within the wide range of structures that are accessible.

Binding Sites↗
PubMed1975

Binary ethylenimine as an inactivant for foot-and-mouth disease virus and its application for vaccine production.

Foot-and-mouth disease virus was inactivated with binary ethylenimine formed apart from or directly in the virus suspension by the cyclization of 2-bromoethylamine hydrobromide or 2-chloroethylamine hydrochloride under alkaline conditions. The inactivation rates with binary ethylenimine prepared apart from the virus suspension in dilute sodium hydroxide with either 2-bromoethylamine hydrobromide or 2-chlorethylamine hydrochloride were higher than with pure ethylenimine. When binary ethylenime was prepared directly in the virus suspension only 2-bromoethylamine hydrobromide gave acceptable inactivation rates. The reduced inactivation rates for binary ethylenimine directly prepared in the virus suspension are due to the different cyclization rates of 2-bromoethylamine hydrobromide and 2-chloroethylamine hydrochloride and to the interference of bicarbonate in the cyclization reaction. The complement fixing antigen of foot-and-mouth disease virus was not affected by binary ethylenimine inactivation. Vaccines prepared with foot-and-mouth disease virus inactivated by binary ethylenimine were comparable in their immunogenicity to vaccines prepared with ethylenimine or N-acetylethylenimine used as inactivants. Application of binary ethylenimine in the preparation of foot-and-mouth disease vaccines considerably reduces the potential danger associated with handling pure ethylenimine and other aziridines.

Animals↗
PubMed1992

Dopaminergic control of locomotion, mouthing, snout contact, and grooming: opposing roles of D1 and D2 receptors.

The study compares the behavioral profiles induced in rats (N = 118) by the D2-dopaminergic receptor agonist quinpirole (0.03 and 0.5 mg/kg), and the D1-agonist SKF38393 (1.25-40 mg/kg), and both agonists administered together. Locomotion and snout contact frequency were reduced by the low but increased by the high dose of quinpirole; SKF38393 also reduced these behaviors and attenuated the effect of the high quinpirole dose. Only the high dose of quinpirole increased the duration of snout contact bouts and the frequency of mouthing; SKF38393 had no effect but in combination with the high dose of quinpirole, it enhanced the performance of these behaviors greatly. The duration of mouthing bouts was not affected by either agonist but was greatly extended when SKF38393 was administered together with the high dose of quinpirole. Grooming was inhibited by both the low and the high dose of quinpirole, and stimulated by the injection of SKF38393 or its addition to the low dose of quinpirole. These findings suggest that snout contact is controlled by modulating the frequency of episodes whereas mouthing is controlled by modulating the duration of episodes. Moreover, although they do not disprove the prevailing notion of D1-D2 receptor synergism, the present data are consistent also with an oppositional model of D1-D2 receptor interaction in the regulation of locomotion, snout contact, mouthing, and grooming in intact animals.

2,3,4,5-Tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-ben↗
PubMed2000

A switch mechanism between locomotion and mouthing implicated in sensitization to quinpirole in rats.

RATIONALE: Chronic treatment with the monoamine oxidase inhibitor (MAOI) clorgyline, blocks locomotor sensitization to the D2/D3 dopamine agonist quinpirole. It is unknown whether this blockade occurs via inhibition of the MAO enzyme or by another mechanism. OBJECTIVES: While clorgyline and moclobemide are equally effective MAOIs, only clorgyline has a high affinity for the MAOI-displaceable quinpirole binding site (MQB). This study compares the effects of both drugs on quinpirole sensitization. METHODS: To examine development of sensitization, rats received clorgyline (1 mg/kg/day), moclobemide (5 mg/kg/day), or vehicle via osmotic mini-pumps and were injected with quinpirole (0.5 mg/kg, s.c.) or saline every 3 days; locomotor and mouthing activity was recorded for each of the eight injections. A similar protocol was used to examine the expression of sensitization in rats previously sensitized to quinpirole. RESULTS: Clorgyline, but not moclobemide, blocked the development of locomotor sensitization to quinpirole. Clorgyline, but not moclobemide, blocked the sensitized locomotor response to quinpirole following the 25th day of treatment. Mouthing showed sensitization in quinpirole-treated rats co-treated with clorgy-line, but not moclobemide; this sensitized mouthing was predominantly directed towards self. Clorgyline and moclobemide equally inhibited MAO-A and had equal effects on tissue concentrations of dopamine, 3,4-dihydroxyphenylacetic acid, and serotonin in the striatum. CONCLUSIONS: Clorgyline (1) inhibits the development and the maintenance of locomotor sensitization to quinpirole by a mechanism that does not involve MAO and (2) changes the sensitized response to quinpirole from locomotion to mouthing. We suggest that clorgy-line affects the response to quinpirole via MQB and that this site acts as a switch that selects the motor pathway for sensitization to quinpirole.

3,4-Dihydroxyphenylacetic Acid↗
PubMed2006

Bilateral conjugacy of movement initiation is retained at the eye but not at the mouth following long-term unilateral facial nerve palsy.

Voluntary eyelid closure and smiling were studied in 11 normal subjects and 11 patients with long-term unilateral facial nerve palsy (FNP). The conjugacy of eyelid movements shown previously for blinks was maintained for voluntary eye closures in normal subjects, with movement onset being synchronous in both eyes. Bilateral onset synchrony of the sides of the mouth was also observed in smiling movements in normal subjects. In FNP patients, initiation of movement of the paretic and non-paretic eyelids was also synchronous, but markedly delayed relative to normal (by 136 ms = 32%). The initiation of bilateral movements at the mouth was similarly delayed, but in contrast to the eyes, it was not synchronous. Central neural processing in the FNP subjects was normal, however, since unilateral movements at the mouth were not delayed. The delays therefore point to considerable additional information processing needed for initiating bilateral facial movements after FNP. The maintenance of bilateral onset synchrony in eyelid closure and its loss in smiling following FNP is an important difference in the neural control of these facial regions. Bilateral conjugacy of eyelid movements is probably crucial for coordinating visual input and was achieved apparently without conscious effort on the part of the patients. Bilateral conjugacy of movements at the sides of the mouth may be less critical for normal function, although patients would very much like to achieve it in order to improve the appearance of their smile. Since the everyday frequency of eyelid movements is considerably greater than that of smiling, it is possible that the preserved eyelid conjugacy in these patients with long-term FNP is merely a product of greater experience. However, if synchrony of movement onset is found to be preserved in patients with acute FNP, then it would suggest that eyelid conjugacy has a privileged status in the neural organisation of the face.

Case-Control Studies↗
PubMed1984

Optimum mouthful for food comminution in human mastication.

The effect of varying the portion of food offered for chewing (termed the mouthful) on aspects of the oral comminution of salted peanuts was investigated on six human subjects. Particle-size distributions, assessed from a sieving analysis, were similar for different mouthfuls, and could be characterized by a sieve size that would pass 80 per cent of the particles by volume in a distribution. As the food weight was increased, (a) the rate of particle-size reduction of the food declined exponentially, (b) the rate of food surface area production increased, (c) the number of chews to swallow the food increased, (d) the number of chews per unit gram to swallow the food decreased, (e) the food-particle sizes that were swallowed increased. It is hypothesized that the volume of food between the teeth at any chewing stroke depends more on food-particle size than on the weight of food in the mouth. The swallowing of small mouthfuls of peanuts may have depended more on the time to wet particles with saliva than particle size.

Arachis↗
PubMed1988

Salivary glucose clearance, dry mouth and pH changes in dental plaque in man.

The aim was to study the effect of different salivary secretion rates on glucose clearance in saliva and on pH changes in dental plaque in man. Eighteen dental students, 21-33 yr old, participated. Dry mouth was induced by injecting methylscopolamine-nitrate submucosally in the labial sulcus. When dry mouth was established, two variables were measured at 1 h intervals, while the salivary flow was recovering: (1) secretion rate of resting and paraffin wax-stimulated whole saliva, and (2) glucose clearance in saliva after ingestion of a glucose tablet. pH changes in dental plaque were studied in 9 of the 18 subjects after a mouth rinse with 10% glucose at two separate occasions, once before and once after an injection of methylscopolamine-nitrate. Higher glucose concentration levels in saliva were found at low than at normal salivary secretion rate. After logarithmic transformation of the salivary glucose concentration values, a biphasic elimination pattern could be seen, with a steeper initial phase followed by a slower one. A critical value for the secretion rate with respect to the salivary glucose clearance time was found to be 0.14 ml/min for resting and 0.62 ml/min for stimulated whole saliva (mean values). The pH changes in dental plaque after the mouth rinse with glucose at extremely low secretion rate were significantly more pronounced than at normal flow rate. Thus, salivary secretion rate affects both the glucose clearance in saliva and the pH changes in dental plaque in man.

Adult↗
PubMed1981

The hyperplastic muscle columns which encroach upon the branch mouths of the coronary arteries and their relation to coronary heart disease.

Hyperplastic muscle columns encroaching upon the branch mouths of the main coronary arteries were revealed in 1 out of every 5 infants, children, juveniles, adolescents, young adults, mature adults and elderly people. They prevailed at the branching points of the first diagonal and first septal vessels and occupied 1/3 to 2/3 of the coronary wall thickness. The presence of hyperplastic muscle bundles encroaching upon the branch mouths of the main coronary arteries was associated with the absence at the respective sites of branch pads or cushions, intimal connective tissue and atherosclerotic lesions. This peculiar microarchitecture was present in 3 times more frequently in patients who died of coronary heart disease than in subjects who died of non-cardiac causes (30% versus 10%). The existence of a relationship was suggested between the hyperplastic muscle columns encroaching upon the branch mouth of an artery and the infarction area in the myocardium supplied by the respective vessel. Likewise, a relationship seemed to exist between hyperplastic muscle columns encroaching upon the branch mouths of the vessels supplying the sinoatrial and atrioventricular nodes and the electrical instability of the heart, particularly of ventricular fibrillation leading to sudden cardiac death.

Adolescent↗
PubMed1992

Effect of prolonged, continuous rectal distention on mouth-to-cecum and colonic transit time in pigs.

The effect of prolonged (6 h), continuous rectal distention on mouth-to-cecum and colonic transit time was studied in four unrestrained pigs. Mouth-to-cecum transit time was determined from samples of cecal efflux using the phenol red dye technique. Colonic transit time was assessed with radiopaque markers that were injected into the cecum before each trial. Rectal distention was applied 2-1/2 h before feeding, during feeding, and 3-1/2 h after feeding. No distention was applied during control conditions. Stools were collected for 48 h after marker application. Rectal distention increased mouth-to-cecum transit time (p < 0.05). Colonic transit time was also prolonged by rectal distention as shown by a significant decrease in the number of markers excreted within 36 h (p < 0.05). Rectal distention for 6 h increased colonic transit time up to 30 h following distention and prolonged mouth-to-cecum transit of a high fat liquid meal.

Animals↗
PubMed2005

Enhancement of indomethacin-induced gastric damage by mouth breathing in rabbits.

Previous studies have reported that mouth breathing is associated with respiratory acidosis. Regarding to the reports that renal elimination of weak acids such as indomethacin is pH dependent, this study was carried out to evaluate the role of mouth breathing on plasma level of indomethacin and indomethacin-induced gastric damage in rabbits. Mouth breathing was induced by surgical ligation of nostrils under general anesthesia. One day after the operation, arterial blood samples were collected for acid-base balance analysis and indomethacin was administered intraperitoneally in a single dose of 40mg/kg. The animals were killed 4h after indomethacin administration and blood samples were collected for spectrofluorometric determination of indomethacin in plasma. The results showed that indomethacin induces more severe gastric damage in nose obstructed rabbits compared with sham and unoperated (UNOP) animals. Acid-base analysis revealed a respiratory acidosis in nose obstructed rabbits and indomethacin level of plasma was significantly higher in nose obstructed animals in comparison with control rabbits. The study shows that mouth breathing can increase the potentiation of indomethacin-induced gastric mucosal damage that may be due to higher level of indomethacin in plasma of nose obstructed animals.

Journal Article↗
PubMed2005

Impact of dry mouth on oral symptoms and function in removable denture wearers in Japan.

OBJECTIVE: The purpose of this study was to determine the association of dry mouth with oral symptoms and function, such as denture instability, discomfort, soreness in denture-bearing tissue, and dissatisfaction with chewing, tasting, or speaking in removable denture wearers. STUDY DESIGN: The subjects were 493 removable denture wearers with a mean age of 67.3 years. Perception of oral dryness was measured by a questionnaire. A multiple logistic regression analysis was used to determine the effect of the dry mouth on oral symptoms and function after controlling for age and gender. RESULTS: Oral dryness during eating was related to dissatisfaction with chewing (odds ratio, 10.5; P < .001) and speaking (odds ratio, 3.5; P < .05) and overall dissatisfaction (odds ratio, 6.3; P < .01) in complete denture wearers. Feeling of dry mouth was likely to be associated with soreness in denture-bearing tissues in both complete and removable partial denture wearers. CONCLUSIONS: There was a significant association of the perception of dry mouth among a group of denture wearers with oral symptoms and function.

Aged↗
PubMed1999

Cortical distribution of Bereitschaftspotential and negative slope potential preceding mouth-opening movements in humans.

Cortical potentials associated with the voluntary movement of various body parts are known as movement-related cortical potentials, which allow evaluation of the cortical efferent function and other higher functions controlling voluntary movement. The cortical potentials have three main components: the Bereitschaftspotential (or 'readiness potential'), the negative slope and the motor potential. Here, the cortical potentials preceding mouth-opening movements were recorded to investigate which of these components could be observed. Electroencephalograms (EEGs) were recorded from 11 electrodes placed over the scalp (F3, Fz, F4, T3, C3, Cz, C4, T4, P3, Pz and P4) according to the international 10-20 system. Electromyograms (EMGs) were recorded from the anterior belly of the digastric and the masseter. The 10 healthy participants were requested to make brisk and self-paced mouth-opening movements. All data were digitized with a sampling frequency of 200 Hz and stored for off-line analysis. Movement-related cortical potentials were obtained by averaging the EEG, using the digastric EMG onset as a trigger signal. The Bereitschaftspotential was recorded as a gradually increasing, bilaterally widespread negativity starting 1.7 s (mean) +/-0.23 s (S.D.) before the onset of the opening movement. The amplitude, which was measured at movement onset, was maximum at Cz (3.8 +/- 1.3 microV). The negative slope was observed 500-600 ms before the movement onset, and the motor potential was not clearly identified, because of postmotion artefacts. The cortical maps of the Bereitschaftspotential and negative slope combined together before to the mouth opening showed a symmetrical distribution with a maximum at the vertex region. The study reveals that the Bereitschaftspotential and the negative slope, two components of the movement-related cortical potentials, can be observed preceding mouth-opening movements and are similar to those associated with other voluntary movements. Findings such as distribution, amplitude and onset of the potentials could provide important information for studying the cortical control of mandibular movements.

Adult↗
PubMed1988

Electrodiffusion of ions approaching the mouth of a conducting membrane channel.

The movement of ions in the aqueous medium as they approach the mouth (radius a) of a conducting membrane channel is analyzed. Starting with the Nernst-Planck and Poisson equations, we derive a nonlinear integrodifferential equation for the electric potential, phi(r), a less than or equal to r less than infinity. The formulation allows deviations from charge neutrality and dependence of phi(r) on ion flux. A numerical solution is obtained by converting the equation to an integral equation that is solved by an iterative method for an assumed mouth potential, combined with a shooting method to adjust the mouth potential until the numerical solution agrees with an asymptotic expansion of the potential at r-a much greater than lambda (lambda = Debye length). Approximate analytic solutions are obtained by assuming charge neutrality (Läuger, 1976) and by linearizing. The linear approximation agrees with the exact solution under most physiological conditions, but the charge-neutrality solution is only valid for r much greater than lambda and thus cannot be used unless a much greater than lambda. Families of curves of ion flux vs. potential drop across the electrolyte, phi(infinity)-phi (a), and of permeant ion density at the channel mouth, n1(a), vs. flux are obtained for different values of a/lambda and S = a d phi/dr(a). If a much greater than lambda and S = O, the maximum flux (which is approached when n1(a)----0) is reduced by 50% compared to the value predicted by the charge-neutrality solution. Access resistance is shown to be a factor a/[2 (a + lambda)] times the published formula (Hille, 1968), which was derived without including deviations from charge neutrality and ion density gradients and hence does not apply when there is no counter-ion current. The results are applied to an idealized diffusion-limited channel with symmetric electrolytes. For S = O, the current/voltage curves saturate at a value dependent on a/lambda; for S greater than O, they increase linearly for large voltage.

Diffusion↗
PubMed1998

'Mouth-feeding' in monkeys after sensorimotor system lesions: an analysis based upon the Denny-Brown collection.

Utilizing the Denny-Brown collection, we investigated an unusual feeding behavior exhibited by monkeys after sequential pre- and post-central gyrus lesions. The behavior involves ingestion of food by placing the lips directly over the food object, i.e., 'mouth-feeding.' Interestingly, this behavior persists long after recovery of the ability to hand-feed. In all of the cases within the collection and in descriptions of mouth-feeding found in the literature, mouth-feeding occurs only after bilateral lesions. We suggest that the co-existence of mouth- and hand-feeding behavior in animals with pre- and post-central gyrus lesions results partly from the sparing of corticospinal projections arising outside these gyri, e.g., the cingulate region, thereby preserving to a certain extent discrete use of the forelimbs.

Animals↗
PubMed2003

A clinical trial of the effect of a mouth-rinse prepared with Lippia sidoides Cham essential oil in dogs with mild gingival disease.

We evaluated the effect of a mouth-rinse prepared using Lippia sidoides essential oil (EO) in dogs with marginal gingivitis. German Shepherd dogs were distributed in two groups: control (control mouth-rinse) and EO (EO mouth-rinse). Both mouth-rinses were applied on the dogs' teeth every 2 days for 2 weeks. At day 0 and day 15, the scores for plaque-bacteria (P), calculus (C), gingivitis (G) and the inflammatory infiltrate (INF) were evaluated blindly. The results were analyzed by the Wilcoxon signed-rank and Mann-Whitney tests (P</=0.05). P, C, G, and INF did not show any alteration in the control group, while in the EO group there were significant reductions in these scores.

Animals↗
PubMed1998

Correlation between preoperative mouth opening and surgical outcome after arthroscopic lysis and lavage in patients with disc displacement without reduction.

PURPOSE: This study was designed to evaluate the efficacy of arthroscopic lysis and lavage for patients with limited mouth opening. The relationship between preoperative mouth opening and the surgical outcome was determined. METHOD: Fourteen patients with 16 internally deranged joints were treated by arthroscopic lysis and lavage. All had received 10.4 (7 to 19) months of nonsurgical treatment before arthroscopy. The preoperative magnetic resonance images showed anterior disc displacement without reduction in all treated joints. RESULTS: Twelve of the 14 patients (86%) showed good reduction in pain and improved range of jaw movement on average follow-up of 28.5 (13 to 66) months. Two patients showed no improvement after arthroscopy and required open surgical procedures. The preoperative mouth opening of the successful group averaged 29.4 (22 to 35) mm, whereas the two failed cases had 10- and 19-mm openings, respectively (P < .05). CONCLUSION: Persistent limitation of mouth opening of more than 22 mm after nonsurgical treatment has a good prognosis when treated by arthroscopic lysis and lavage. However, those with greater limitation should probably have earlier surgical intervention.

Adult↗
PubMed1971

The growth and persistence of foot-and-mouth disease virus in the bovine mammary gland.

In animals exposed to foot-and-mouth disease virus by indirect contact, virus was recovered from the blood, milk, pharynx, vagina and rectum for variable periods of time before clinical disease was apparent. Virus instilled into the mammary gland multiplied rapidly and virus concentrations greater than 10(7) p.f.u./ml. were recorded within 8-32 hr., depending on the virus strain and dose inoculated. Virus multiplication was accompanied by clinical signs of mastitis but the classical signs of foot-and-mouth disease did not appear for 52-117 hr. Dissemination of virus from the mammary gland occurred within 4-24 hr. and in some animals samples taken from the pharynx, mouth, nose and vagina contained virus for periods up to 97 hr. before the appearance of vesicular lesions. Virus production in the udder declined with the appearance of virus neutralizing activity in the blood and the milk but persisted in some animals for periods of 3-7 weeks. The ability of foot-and-mouth disease virus to persist in mammary tissue was confirmed by the demonstration of virus multiplication in the udders of immune animals.

Animals↗