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 1,261 records · Page 70Linked to original sources
PubMed1993

Assessment of diaphragm function using mouth pressure twitches in chronic obstructive pulmonary disease patients.

The relative invasiveness of the balloon catheter technique in measuring twitch transdiaphragmatic pressure (Pdit) limits its clinical use. By phrenic stimulation we obtained swings in mouth pressure (Pmt) in six COPD patients (age 50 to 72, FEV1 18 to 48% of predicted) at relaxed FRC (rFRC) and during graded inspiratory efforts (IE; twitch occlusion, TO). At rFRC, Pmt was damped and time lagged relative to the esophageal pressure twitch (Pes(t)), as if pressure had equilibrated through an RC system. Pmt was not correlated with Pdit. Conversely, Pmt and Pes(t) were always well matched during IE [Pmt = 0.971 (SEM +/- 0.028) Pes(t), r > 0.89], possibly in relation to a decrease in upper airway compliance or more uniform pleural pressure swings. Pmt decreased with the level of voluntary diaphragmatic contraction (Pdivol) in proportion to Pdit, reflecting a progressive increase in the level of diaphragm activation. During IE, Pmt was closely related to the voluntary mouth pressure in five subjects but not in the remaining subject, indicating intersubject variability in the level of diaphragmatic recruitment relative to other inspiratory muscles. We submit that measuring Pm during inspiratory efforts upon which bilateral phrenic stimulation is superimposed offers a relatively simple method for the assessment of diaphragm activation, potentially applicable in the clinical field.

Aged↗
PubMed1984

Tracheal mucus clearance in high-frequency oscillation. II: Chest wall versus mouth oscillation.

We compared the tracheal mucus clearance rate (TMCR) in anesthetized dogs during spontaneous breathing (SB), ventilation by high-frequency oscillation at the airway opening (HFO/AO), and ventilation by high-frequency oscillation of the chest wall (HFO/CW). The HFO/AO was carried out by using a piston pump with a high impedance transverse flow at the proximal end of the endotracheal tube; HFO/CW was effected by creating rapid pressure oscillations in an air-filled cuff wrapped around the lower thorax of the animal, causing small tidal volumes at the mouth. The TMCR was measured by observing the rate of displacement of a charcoal marker in the lower trachea; a fiberoptic bronchoscope was used to deposit the marker before each experiment and to relocate it after a 5-min run. In 7 dogs, mean TMCR during control (SB) was 8.9 +/- 3.5 mm/min. At 13 Hz with an oscillatory tidal volume (VTO) of 1.5 ml/kg, mean TMCR was 240% of control with HFO/CW (p less than 0.001) and 76% of control with HFO/AO (NS). During HFO/AO at 20 Hz and a VTO of 3 ml/kg, mean TMCR was 97% of control. We conclude that high-frequency ventilation by rapid chest wall compression enhances tracheal mucus clearance when compared with spontaneous breathing, whereas high-frequency oscillation at the mouth does not.

Animals↗
PubMed1984

The volume of saliva in the mouth before and after swallowing.

In 20 male and 20 female adult subjects, the volume of saliva in the mouth before (VMAX) and after (RESID) swallowing was determined. RESID could be computed by measuring the potassium and chloride concentrations in unstimulated saliva and in the expectorate after a five-second rinse with 5 ml of water immediately following a swallow. The mean value of RESID after a normal swallow was significantly higher in males (0.87 ml) than in females (0.66 ml). After a forced swallow, RESID was only slightly but significantly reduced, being 0.82 ml and 0.60 ml in males and females, respectively. The volume of saliva normally swallowed was calculated from the unstimulated salivary flow rate and the normal swallowing frequency. The mean value of VMAX (RESID plus volume normally swallowed) in males was 1.19 ml, which was slightly but not significantly higher than that in females (0.96 ml). When water was infused into the mouth at increasing flow rates, there was an increase in VMAX and in both the volume of fluid swallowed and the swallowing frequency.

Adolescent↗
PubMed1985

The effects of different concentrations of sucrose, fructose, and glucose on pH changes by Streptococcus mitior in an artificial mouth.

The aim of this study was to determine the effects of the initial sucrose (S) concentration, as well as those of fructose (F), glucose (G), and invert sugar (F/G), on the pH developed by a layer of S. mitior, to represent dental plaque, in an artificial mouth which simulates the process of oral sugar clearance. At S, F. G, and F/G concentrations of 2% and with normal oral sugar clearance rates, the bacteria produced a smaller pH fall from S than from the other sugars; at initial concentrations of 20%, however, the differences were not significant. With constant S concentrations of 0.5-35%, the minimum pH reached was 4.03 +/- 0.14 (S.D.); with S concentrations of 50% and above, slightly but significantly higher values (4.41 +/- 0.34) occurred. However, with normal sugar clearance, the pH fall was much less than with a constant concentration and was dependent on the S concentration over the range of 0-10%, but was independent at higher concentrations. Exposure of the bacteria to S for as short a period as two min during normal sugar clearance gave a nearly maximum pH fall. This suggests that rinsing the mouth with water more than two min after consumption of sucrose in liquid form will have very little effect in reducing the pH fall in dental plaque. A more appropriate method for reducing acid formation by dental plaque would be consumption of a salivary stimulant which would increase the flow rate and buffer capacity of the saliva.

Acids↗
PubMed1989

Estimation of the velocity of the salivary film at some different locations in the mouth.

Previously, we studied the clearance rates of KCl from agarose gels positioned at different locations in the mouth, and showed that the rates were much slower than when clearance was into a well-stirred solution. We designed the present in vitro study to test the effect on KCl clearance of the velocity of a 0.1-mm-thick film of water flowing over an agarose gel of the same diameter and composition as those used in vivo. The thickness of the salivary film overlying dental plaque has been estimated to be about 0.1 mm, and we assumed that when clearance rates in vitro matched those found in vivo, velocities of the fluid film (in vitro) and the salivary film (in vivo) must be equal. On this basis, it was calculated in the present experiments that when salivary flow was unstimulated, the velocity of the salivary film at the level of the teeth varied between about 0.8 mm/min (upper-anterior buccal region) and 8.0 mm/min (lower-anterior lingual region). When salivary flow was stimulated, this was estimated to increase the velocity of the salivary film from 2 to 40 times, depending on the location in the mouth. It is postulated that the slow movement of the salivary film when flow is unstimulated allows for accumulation of diffusants from dental plaque, which reduces the concentration gradient for diffusion from plaque and prolongs the clearance time of such metabolic products as acid.

Chemical Phenomena↗
PubMed1990

Foot-and-mouth disease virus in the llama (Lama glama): diagnosis, transmission, and susceptibility.

Foot-and-mouth disease virus (FMDV) was shown to be transmitted from either cattle to llamas, llamas to swine (interspecies), or llamas to llamas (intraspecies). Response to FMDV varied greatly in the 6 llamas studied; 3 llamas developed generalized clinical disease with mild pyrexia, 2 after intradermolingual inoculation, and 1 after exposure to a calf infected with FMDV serotype A24. Another contact llama developed vesicular lesions on all 4 extremities but no oral lesions. Two contact llamas, in separate study groups, did not seroconvert or develop clinical signs of FMDV infection. All 4 llamas showing clinical disease developed virus-neutralizing antibodies against FMDV A24 and antibodies against the virus-infection-associated antigen. Virus-neutralizing antibody titers remained elevated for over 200 days postinoculation or exposure. Antibodies to virus-infection-associated antigen were detected several days after virus-neutralizing antibody appeared and became weaker 100-125 days post-FMDV exposure in 3 of the 4 clinically affected llamas. One inoculated llama was still positive for virus-infection-associated antigen at 360 days after inoculation. Foot-and-mouth disease virus A24 was not detected from esophageal-pharyngeal fluid specimens beyond 8 days postexposure using in vitro techniques.

Animals↗
PubMed1995

African swine fever interference with foot-and-mouth disease infection and seroconversion in pigs.

Initial oral infection of pigs with either highly virulent (L-60) or moderately virulent (DR-2) African swine fever virus (ASFV), followed in 3 days with exposure to foot-and-mouth disease virus (FMDV) (tongue inoculation and contact), failed to cause FMDV infection or seroconversion in 18 of 22 L-60-infected pigs and 13 of 34 DR-2-infected pigs. Of the 13 DR-2-infected pigs remaining free of foot-and-mouth disease (FMD), 2 pigs survived to 24 days without antibody to FMDV, despite constant contact with clinically infected pigs with FMD. Three other DR-2-infected pigs never developed FMD lesions but did develop low levels of antibody to FMDV by day 17. A group of larger pig (in which DR-2 is less virulent) infected with DR-2 and then FMDV had a rapid but suppressed immune response to FMDV. Contact pigs introduced 3 days postinoculation and inoculated with FMDV only all became infected with ASFV by contact and died. This remarkably long lasting 1-way interference with FMD infection during acute and subacute African swine fever was not anticipated. Infection with ASFV may have blocked the initial target cells (possibly dendritic cells) necessary for establishment of FMDV infection.

African Swine Fever↗
PubMed2004

Peak or plateau maximal inspiratory mouth pressure: which is best?

There is no clear evidence as to how maximal inspiratory mouth pressure (PI,max) should be measured, although plateau pressures sustained for 1 s and measured at residual volume (RV) are usually recommended. Peak and plateau PI,max were measured at RV and at functional residual capacity (FRC) in 533 healthy subjects (aged 10-90 yrs) in order to comparably test all PI,max measurements for their predictors, reproducibility and normal values. Plateau pressures accounted for 82.0-86.3%, of peak pressures. Peak and plateau pressures measured at FRC accounted for 84.3-90.5% of pressures at RV, and were highly correlated. Age was negatively predictive and weight and body mass index positively predictive of PI,max, but regression parameters were low. All PI,max measurements were comparable when calculating regression parameters, between-subject variability and reproducibility. In conclusion, peak and plateau maximal inspiratory mouth pressure are comparably useful for the assessment of inspiratory muscle strength and can be reliably measured at functional residual capacity and at residual volume. Regression equations are of low impact in predicting normal values due to the weak influence of demographic and anthropometric factors and to the high unexplained between-subject-variability. Age-related 5th percentiles can indicate the lower limit of the normal range.

Adolescent↗
PubMed1998

Maximum rate of change in oesophageal pressure assessed from unoccluded breaths: an option where mouth occlusion pressure is impractical.

The mouth occlusion pressure 100 ms after onset of inspiration (P0.1) is considered a clinically useful measure of the combined output of the respiratory centre and muscle pump. However, theoretical and practical difficulties can arise when using P0.1 in the assessment of patients with severe chronic obstructive pulmonary disease (COPD). It was hypothesized that the maximum rate of change in oesophageal pressure (dPoes,max/dt) may be an alternative to P0.1. To test this hypothesis P0.1 was compared with mean dPoes,max/dt measured from neighbouring unoccluded breaths in five normal subjects during CO2 rebreathing. In all subjects a close correlation was found between both dPoes,max/dt and P0.1 and carbon dioxide tension (PCO2). In six patients with severe COPD performing exhaustive treadmill walks, dPoes,max/dt was found to increase progressively with walking time. Mean dPoes,max/dt at the start was 6.2 cmH2O x 100 ms(-1) and at the finish was 18.7 cmH2O x 100 ms(-1) (p<0.03). In conclusion, the maximum rate of change in oesophageal pressure measured from unoccluded breaths could be an alternative in circumstances where it is not feasible to use measurements of the mouth occlusion pressure 100 ms after onset of inspiration.

Aged↗
PubMed2006

Formulation and optimization of mouth dissolve tablets containing rofecoxib solid dispersion.

The purpose of the present investigation was to increase the solubility and dissolution rate of rofecoxib by the preparation of its solid dispersion with polyvinyl pyrrolidone K30 (PVP K30) using solvent evaporation method. Drug-polymer interactions were investigated using differential scanning calorimetry (DSC), x-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). For the preparation of rofecoxib mouth dissolve tablets, its 1:9 solid dispersion with PVP K30 was used with various disintegrants and sublimable materials. In an attempt to construct a statistical model for the prediction of disintegration time and percentage friability, a 3(2) randomized full and reduced factorial design was used to optimize the influence of the amounts of superdisintegrant and subliming agent. The obtained results showed that dispersion of the drug in the polymer considerably enhanced the dissolution rate. The drug-to-carrier ratio was the controlling factor for dissolution improvement. FTIR spectra revealed no chemical incompatibility between the drug and PVP K30. As indicated from XRD and DSC data, rofecoxib was in the amorphous form, which explains the better dissolution rate of the drug from its solid dispersions. Concerning the optimization study, the multiple regression analysis revealed that an optimum concentration of camphor and a higher percentage of crospovidone are required for obtaining rapidly disintegrating tablets. In conclusion, this investigation demonstrated the potential of experimental design in understanding the effect of the formulation variables on the quality of mouth dissolve tablets containing solid dispersion of a hydrophobic drug.

Absorption↗
PubMed1994

Effect of a new oral somatostatin analog (SDZ CO 611) on gastric emptying, mouth to cecum transit time, and pancreatic and gut hormone release in normal male subjects.

Sixteen healthy male volunteers participated in a randomized, double blind, parallel groups study. Subjects received either 1 or 5 mg SDZ CO 611 (a new, orally active somatostatin analog) twice daily over a 14-day period and acted as their own controls. Gastric emptying of 99mTc and mouth to cecum transit time, as measured by the breath hydrogen technique, after a mixed meal containing lactulose and 99mTc-diethylenetriaminepentaacetate, were assessed once before, twice during, and once after the period of study medication. Gastric emptying of 99mTc was significantly accelerated by the higher dose of SDZ CO 611, whereas mouth to cecum transit time was prolonged by the drug in a dose-dependent manner. Both doses of SDZ CO 611 led to suppression of the fasting level and postprandial release of several gastrointestinal and pancreatic hormones. This effect was more marked in those subjects taking 10 mg/day of the study medication. Motilin and pancreatic polypeptide were the most sensitive to the inhibitory actions of the analog. Glucose tolerance was significantly impaired by the 10-mg dose of the drug. We conclude that this new, orally active derivative of somatostatin is as effective on the gastrointestinal tract as the sc somatostatin analog octreotide. It would, therefore, be a useful advance in the treatment of gastroenteropancreatic tumors.

Administration, Oral↗
PubMed1975

Control of mouth opening and pharynx protrusion during feeding in the sea anemone Calliactis parasitica.

1. Activity in all three known conducting systems (the nerve net, SS1, and SS2) may accompany feeding in Calliactis. The most marked response is an increase in pulse frequency in the SS2 (the endodermal slow conducting system) during mouth opening and pharynx protrusion. 2. Electrical stimulation of the SS2 at a frequency of one shock every 5 s elicits mouth opening and pharynx protrusion in the absence of food. 3. A rise in SS2 pulse frequency is also evoked by food extracts, some amino acids, and in particular by the tripeptide reduced glutathione, which produces a response at a concentration of 10(-5) M. 4. Although the SS2 is an endodermal system, the receptors involved in the response to food appear to be ectodermal. 5. The epithelium that lines the pharynx conducts SS1 pulses, but there is some evidence for polarization of conduction.

Action Potentials↗
PubMed1979

Complete reconstruction of the chin and floor of the mouth.

A method of reconstruction of the entire floor of the mouth and chin is presented, utilizing interdigitated ventral tongue flaps for reconstruction of the floor of the mouth, and a deltopectoral flap for reconstruction of the chin, which, even with loss of bony support of the mandible, provides a watertight, competent oral sphincter with adequate communication and nutrition.

Chin↗
PubMed1981

Lymphatics of the floor of the mouth and neck: anatomical studies related to contralateral drainage pathways.

An anatomical study was made to determine the role of the regional lymphatic drainage pathways in contralateral flow from the floor of the mouth in the dog. Microsurgical techniques were used to cannulate and perfuse a lymphatic vessel. Following a two hour infusion, bilateral radical neck dissections were performed. An efferent upper jugular communicating pathway was repeatedly identified which crossed the midline and drained into the contralateral subdigastric group of nodes. These studies demonstrate a precise role for the regional lymphatic drainage pathways in contralateral flow from the floor of the mouth.

Animals↗
PubMed1988

Alcohol and tobacco consumption in cancer of the mouth, pharynx, and larynx: a study of 316 female patients.

Three hundred sixteen female patients with cancer of the larynx, pharynx, and mouth were examined and the following cancer sites were compared with respect to alcohol and tobacco consumption: oropharynx, hypopharynx, larynx, epilarynx, lip, and mouth. The mean daily tobacco consumption of smokers and ex-smokers was not significantly different between cancer locations; however, significant differences between cancer sites were observed with regard to the proportion of nonsmokers. The percentage of nonsmokers was the highest for cancer of the lips and the lowest for cancer of the epilarynx. Cancer locations differed significantly depending on daily alcohol consumption. Consumption was the lowest for patients with cancer of the lips. The percentage of nondrinkers was high for cancers of the lips and larynx and low for cancer of the epilarynx. Examination of the nonsmoking/nondrinking females (27.2%) did not reveal any features specific to this group, except that the patients were older.

Alcohol Drinking↗
PubMed2005

Bacteria in the mouth.

There are many infectious agents found within the oral cavity. Bacteria form an important group of micro-organisms found in both healthy and diseased mouths. The current article will discuss those bacteria resident within the mouth and review the oral diseases with which they are associated.

Actinomycosis, Cervicofacial↗
PubMed1984

Frequency dependent phase and amplitude differences between simulated mouth and pleural pressures during panting. Demonstration with a mechanical model.

A mechanical model was employed to examine phase and amplitude relationships between simulated pleural and mouth pressures during panting at different frequencies with and without lower airway obstruction and with rigid or flaccid extrathoracic airways. Results confirm the hypothesis that, in the presence of lower airways obstruction, compliant extrathoracic airways act as a shunt impedance. Consequently, mouth pressure changes may be out of phase with and underestimate changes in pleural pressure, affecting the measurement of thoracic gas volume.

Humans↗
PubMed1985

Respiratory drive in nonsmokers and smokers assessed by passive tilt and mouth occlusion pressure. Response to rebreathing carbon dioxide.

The purpose of the present investigation was to assess respiratory center function in smokers using (1) measurement of mouth occlusion pressure during carbon dioxide rebreathing and (2) noninvasive measurement of breathing pattern during passive upright tilt. The breathing patterns of 20 normal nonsmokers and 20 smokers without major obstruction of the airways were monitored noninvasively with respiratory inductive plethysmography for 15 minutes in the supine position and then after 90 degrees head-up passive tilt to the standing position. In nonsmokers, significant increases from supine to standing positions included the following: (1) minute ventilation from 6.22 +/- 1.47 to 7.32 +/- 1.16 L/min (p less than 0.05); (2) tidal volume from 368 +/- 93 to 462 +/- 108 ml (p less than 0.01); and (3) mean inspiratory flow from 263 +/- 61 to 320 +/- 43 ml/sec (p less than 0.01). Responses of smokers to tilt were variable; 14 showed changes similar to nonsmokers, but six showed no increase of ventilation and respiratory drive upon tilting. The latter also showed blunted response to rebreathing carbon dioxide in the supine position as estimated by plotting mouth occlusion pressures against end-tidal carbon dioxide tension. These data suggest that disturbances of respiratory center control are common in smokers without major obstruction of the airways.

Adult↗