bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regulation of Rat Adrenal Vasoactive Intestinal Peptide Content: Effects of Adrenocorticotropic Hormone Treatment and Changes in Dietary Sodium Intake
Authors: Hinson J. P. , Renshaw D. , Carroll M. , Kapas S. 
Published: March 2003

AbstractVasoactive intestinal peptide (VIP) is well established as a paracrine regulator of adrenal function. It is present in nerves supplying the adrenal cortex, although previous studies have found that the amount of VIP in the outer zones of the rat adrenal is not affected by ligating the splanchnic nerve supplying the adrenal gland. The present studies were designed to investigate the mechanisms involved in regulating the VIP content of the rat adrenal gland. This study examined the effects of changes in electrolyte balance and adrenocorticotropic hormone (ACTH) administration on the adrenal content of VIP as measured by radioimmunoassay. Rats on a low sodium diet had a significantly increased capsular/zona glomerulosa immunoreactive VIP (irVIP) level, while rats on a high sodium diet had suppressed levels relative to controls. Changes in dietary sodium did not affect inner zone/medullary VIP content. Administration of ACTH caused a decrease in irVIP levels in the capsular/zona glomerulosa portion of the adrenal gland but had no effect on the inner zone/medulla. Analysis of mRNA encoding VIP revealed a large increase in expression of VIP in the sodium‐deplete group compared with the control, with no change in VIP expression in the sodium‐loaded group. ACTH treatment was found to significantly decrease VIP mRNA levels in the capsular portion. Neither ACTH treatment nor changes in sodium intake affected inner zones/medullary VIP message. These data suggest that VIP in the capsule and zona glomerulosa region of the adrenal cortex is regulated in response to the physiological status of the animal, with changes in capsular/zona glomerulosa VIP correlating with changes in zona glomerulosa function.
Differential Expression of Vasoactive Intestinal Polypeptide Receptor 1 and 2 mRNA in Murine Intestinal T Lymphocyte Subtypes
Authors: Qian B.‐F. , Hammarström M.‐L. , Danielsson Å. 
Published: March 2003

AbstractNeuropeptides may exert a variety of effects on the immune cells at both systemic and mucosal immune sites. The immunoregulatory properties refer to the ability of physiological signals and pathways to influence various immune functions. Vasoactive intestinal polypeptide (VIP), a neuropeptide present in high concentration in gut, was studied for its production and receptor expression in intraepithelial and lamina propria T lymphocytes of mouse intestine. Using reverse transcription‐polymerase chain reaction (RT‐PCR) analysis, it was demonstrated that VIP receptor 1 (VIPR1) was constantly expressed in intraepithelial and lamina propria T lymphocytes from both small and large intestine. In contrast, VIPR2 was identified only in T cells from small intestine. Further studies on purified subpopulations of T lymphocytes indicated the existence of VIPR2 in CD8+ T cells, but not CD4+ and CD4CD8 double negative T cells, although all these three subpopulations displayed VIPR1. In addition, VIPR1 mRNA was detected in splenic T lymphocytes, but no signal was obtained for VIPR2 mRNA, even after stimulation of the cells with anti‐CD3ε‐chain mAb, phorbol 12‐myristate 13‐acetate (PMA) and/or VIP. The presence of VIP receptor(s) on intestinal T lymphocytes was supported by the detection of VIP on the cell surface using dual colour immunoflowcytometry. In‐vitro treatment with VIP resulted in a tendency towards an increased size of the VIP immunoreactive T cell population and significantly enhanced the average immunofluorescence intensity of the surface labelling. This indicates that the receptors are partially occupied by locally produced VIP in vivo and that more peptide molecules can be bound on the lymphocytes when needed, released and accumulated in higher concentration at the action sites. We failed to detect the expression of VIP mRNA in T lymphocytes, from either intestine or spleen. These observations support that VIP may be an important immune modulator in gut acting through specific receptors on T lymphocytes. The differential mRNA expression of VIP receptor subtypes in cells with different phenotypes and in different immune compartments may suggest diverse regulatory roles of the neuropeptide in immune responses.
Modulation of Gonadotropin II Release by K+ Channel Blockers in Goldfish Gonadotropes: A Novel Stimulatory Action of 4‐Aminopyridine
Authors: Wong C. J. H. , Kwong P. , Johnson J. D. , Yunker W. K. , Chang J. P. 
Published: March 2003

AbstractThe effects of K+ channel blockers on basal gonadotropin II (GTH‐II) release were examined in cultured goldfish gonadotropes. Tetraethylammonium (TEA) inhibited basal GTH‐II release, whereas 4‐aminopyridine (4‐AP) increased basal release, although both K+ channel blockers generated increases in [Ca2+]i. Other K+ channel blockers had no significant effect on GTH‐II release. We examined whether Ca2+ entry that arises from blockade of K+ channels by 4‐AP mediates the secretory response. Secretion evoked by 4‐AP was slightly reduced by TEA but was unaffected by reducing Ca2+ entry using either an inhibitor of Ca2+ channels, verapamil, or nominally Ca2+‐free medium. In contrast, the Ca2+ signal evoked by 4‐AP was largely blocked by Ca2+‐free medium, as predicted by its inhibitory action on K+ channels. Together, these data suggest that the hormone release response to 4‐AP is independent of entry of extracellular Ca2+. Finally, the mechanism of hormone release evoked by 4‐AP appeared to be independent of mechanism(s) evoked by caffeine since 4‐AP did not affect caffeine‐evoked release and caffeine did not affect 4‐AP evoked release. That both 4‐AP and TEA generated Ca2+ signals but affected hormone release in either an extracellular Ca2+ independent (4‐AP) or inhibitory (TEA) manner suggests that Ca2+ entry is linked to GTH‐II secretion in a highly nonlinear fashion.
Response to Male Odours in Progestin Receptor‐ and Oestrogen Receptor‐Containing Cells in Female Rat Brain
Authors: Bennett A. L. , Gréco B. , Blasberg M. E. , Blaustein J. D. 
Published: March 2003

AbstractSensory cues from male rats, such as odours and vaginal‐cervical stimulation (VCS), play a modulatory role in female rat sexual behaviour. For example, exposure to male odours and VCS appears to be at least partially responsible for increases in sexual behaviour following repeated mating of oestradiol‐primed female rats. Although there is evidence that VCS influences sexual behaviour via a ligand‐independent progestin receptor (PR)‐dependent mechanism, the mechanism by which odours influence sexual behaviour is not known. We tested the hypothesis that, similar to VCS, the effects of male odours on sexual behaviour are mediated by progestin receptors. Female rats were injected with the progestin antagonist, RU486, or oil vehicle and were then exposed to male‐soiled bedding or clean bedding. Although exposure to male‐soiled bedding resulted in higher levels of Fos immunoreactivity in brain areas associated with female sexual behaviour, the progestin antagonist did not reduce this effect. Furthermore, there was minimal coexpression of odour‐induced Fos and progestin receptors in brain areas associated with female sexual behaviour. Together, these results suggest that the effects of male odours are not mediated by a PR‐dependent mechanism. Therefore, we tested the hypothesis that oestrogen receptor (ER)‐containing cells are involved in the effects of olfactory cues. Although there was virtually no coexpression of ERβ and odour‐induced Fos in brain areas associated with female sexual behaviour, exposure to male odours slightly increased the number of cells coexpressing ERα and odour‐induced Fos in the posterodorsal medial amygdala. Although, these results do not support the hypothesis that the effects of odours are mediated by a PR‐dependent mechanism, they suggest that integration of male odours and hormonal cues may occur in ERα‐containing cells in the posterodorsal medial amygdala.
Daily Rhythms in Glucose Metabolism: Suprachiasmatic Nucleus Output to Peripheral Tissue
Authors: La Fleur S. E. 
Published: March 2003

AbstractThe body has developed several control mechanisms to maintain plasma glucose concentrations within strict boundaries. Within those physiological boundaries, a clear daily rhythm in plasma glucose concentrations is present; this rhythm depends on the biological clock, which is located in the hypothalamic suprachiasmatic nucleus (SCN), and is independent of the daily rhythm in food intake. Interestingly, there is also a daily rhythm in glucose uptake, which also depends on the SCN and follows the same pattern as the daily rhythm in plasma glucose concentrations; both rise before the onset of activity. Thus, the SCN prepares the individual for the upcoming activity period in two different ways: by increasing plasma glucose concentrations and by facilitating tissue glucose uptake. In addition to this anticipation of glucose metabolism to expected glucose demands, the SCN also influences, depending on the time of the day, the responses of pancreas and liver to abrupt glucose changes (such as a glucose rise after a meal or hypoglycaemia). This review presents the view that the SCN uses different routes to (i) maintain daily glucose balance and (ii) set the level of the endocrine response to abrupt blood glucose changes.
Psychometric profiles of temporomandibular disorder patients in southern Thailand
Authors: Sirirungrojying S. , Srisintorn S. , Akkayanont P. 
Published: March 2003

summaryPsychological factors of temporomandibular disorder patients are believed to have a significant role in the aetiology and maintenance of the disorders. Sixty‐two temporomandibular disorder patients, 67 dental patients, and 70 asymptomatic subjects were compared for psychometric profile by using a self‐report symptom inventory. Temporomandibular disorder patients were more depressed and anxious than dental patients and asymptomatic subjects, and were also more somatized than asymptomatic subjects.
Quid test and clinical findings in a TMD treatment‐seeking population
Authors: MAURO G. , TAGLIAFERRO G. , MONTINI M. , MACALUSO G. M. 
Published: March 2003

The aim of the present study was to investigate the response pattern to ‘QUID test’ (Italian analogue of the ‘McGill Pain Questionnaire’) and the clinical aspects of a TMD seeking care population.A total of 229 consecutive patients (mean age 35·9 years) completed the QUID test and underwent a complete clinical examination. An analysis of pain descriptors was also performed. This population was divided in six groups according to their clinical characteristics: 1. TMD: pain at the moment of the examination, positive findings for TMD. 2. eTMD: history of TMD, episodic pain, no clinical findings at present. 3. Headache (H): main complaint. 4. Neck pain (N): main complaint. 5. Atypical Facial Pain (AFP): facial pain not fulfilling other criteria (IHS 12·8). 6. No Orofacial Pain (NOFP): no pain disturbances. Statistical analysis was performed using t and chi‐squared tests. Significance level was set to 0·05. The percentages of the six groups were: TMD 53·71%, eTMD 9·17%, H 4·80%, N 1·31%, AFP 6·11%, NOFP 24·89%. Significant differences were found in: – pain intensity between H and TMD (P=0·034), and between AFP and eTMD (P=0·027); – hypermobility and cervical problems between NOFP and TMD (P=0·021 and 0·0001, respectively); – presence of psychobehavioural factors (axis II) between eTMD and AFP (P=0·05); – type and distribution of words chosen: particularly five descriptors showed a significantly different pattern of distribution; – affective component of pain experience (PRIrcA): highest for the AFP group.
Biofeedback experiments with a submaximal jaw closing force
Authors: JAKSTAT H. A. 
Published: March 2003

Temporomandibular disorders are often accompanied with pain in the elevator muscles such as Mm. Masseterici and Mm. Temporales. In most experiments measurement of the closing force of these muscles was conducted with maximum bite force using EMG‐devices.The experiments presented here were conducted using visual or audible biofeedback using force transducers. Visual feedback was presented on a computer screen using geometrical graphics. Audible feedback used two different signals, the frequency of these audio signals was modulated. The force was chosen between 5 and 30 N, which is near the forces actually used for chewing, but far less than maximum clenching force. The persons chosen for the experiments were divided into two groups: A group of younger persons did not wear any removable dentures, a group of older persons was wearing a total prosthesis of the upper and lower jaw. The results were processed statistically and graphically.The goal for the persons conducting the experiments was to select a closing force as near as possible to the given force which was shown using the biofeedback. The actual force used by the person was also shown.There were no statistically significant differences in the results using 5, 10 or 30 N as given force. Results showed that older edentulous patients can modulate the chewing force not as exactly as younger persons. Especially when using low closing forces (5 N) the edentulous persons showed less exactness in reaching the given closing force.The results of the experiments may be used to develop a test to determine the capability of older patients to perform exact closing (and chewing) movements.
Twitch forces in human masseter during experimental muscle pain
Authors: SVENSSON P. , SOHN M. K. , GRAVEN‐NIELSEN T. , ARENDT‐NIELSEN L. 
Published: March 2003

Motor control strategies in relation to pain are not completely understood. Decreased firing rates of single motor units (SMU), but with a constant bite force have recently been demonstrated in the presence of masseter pain suggesting the existence of compensatory mechanisms (Sohn et al., 2000). The aim of this study was to describe twitch force characteristics of masseter SMU using spike triggered averaging (STA) before and during experimental muscle pain. Ten healthy subjects (20–29 years) participated. Fine wire electrodes were inserted into the masseter to record SMU activity. Subjects performed an isometric contraction on a force transducer (Kistler, Switzerland) with their incisor teeth to keep the SMU steady firing. A template‐matching procedure was used to identify SMU and the corresponding force was determined with STA. One‐min test series were recorded before 1, 4, 7, 10, 15 and 20 min after injection of 0·2 mL 100 µg mL−1 capsaicin into the masseter. Pain was continuously scored on 10‐cm visual analogue scales (VAS). The amplitude of twitch force and contraction time was measured. Injection of capsaicin into the masseter caused a deep, painful sensation with a VAS peak of 5·5 ± 0·6 cm. Twitch amplitudes were significantly influenced by pain (anova: P < 0·001) with higher amplitudes during pain‐1‐min (56·1 ± 10·7 mN) and pain‐4‐min (53·5 ± 11·9 mN) compared with before pain (33·9 ± 11·6 mN; P < 0·05). The contraction time (51·6 ± 4·4 ms) was not significantly changed during pain (anova: P > 0·429). The present study suggests that increased twitch force during painful muscle contraction could compensate for decreased firing rates of SMU.
Handy measurement for tongue motion and coordination with laryngeal elevation at swallowing
Authors: TSUGA K. , HAYASHI R. , AKAGAWA Y. 
Published: March 2003

In managing elderly people's quality of life, dysphagia is a critical problem because of its presumable relation to pneumonia. In the oral stage of swallowing, the tongue involves profoundly and its proper performance is necessary for bolus forming and transferring to the pharynx. In this regard, informative videofluorography, however, requires special facilities and inevitable exposure to radiation. For the present study we prototyped a device for a safe and handy objective estimation of tongue motion and its coordination with laryngeal elevation at swallowing.Ten healthy subjects were asked five times to swallow 5 mL of water. The tongue pressure was recorded by means of two strain gauge pressure transducers aligned in 20 mm distance on a brass strap placed along the palatal midline. Laryngeal vibration was recorded with piezo‐electric acceleration transducer. Time difference between each pressure onset of the anteriorly/posteriorly located transducers and impulsive output of laryngeal vibration were measured.Pressure onset of the anteriorly located transducer preceded posterior one for 294 ± 164 ms. Considering the distance of transducers, tongue squeezed at 93 ± 60 mm s−1 speed. Laryngeal vibration occurred 671 ± 175 ms after the anterior pressure onset. There was a large variation in these parameters between subjects. The total recording time for each subject was <10 min. Although the information is limited, the developed device could handily describe some aspects of tongue motion and its coordination with laryngeal elevation.
Treatment received, treatment demand and treatment need for temporomandibular disorders in 35‐year‐old subjects
Authors: MAGNUSSON T. , EGERMARK I. , CARLSSON G. E. 
Published: March 2003

An epidemiology sample of 114 subjects was followed longitudinally from the age of 15–35 years concerning received treatment, treatment demand and treatment need for temporomandibular disorders (TMD). Some kind of TMD treatment had been provided to 18% of the subjects during the 20‐year follow‐up period. Eighty‐five per cent of those who had received TMD treatment previously reported that the treatment had a positive effect on their symptoms. The estimated present need of treatment was 11%, but, in line with several other investigations, the active demand for such treatment was much less (3%). From 15 to 25 years of age, a small but gradual increase in clinical signs of dysfunction was found. From the age of 25–35 years, however, a significant reduction of such signs was noted. One explanation to this reduction of clinical signs of TMD might be the stomatognathic treatment performed. It was concluded that 18% had received some TMD treatment during the 20‐year follow‐up period. Only 3% had a demand for such treatment at 35 years of age.This study was supported by the Research Council, County of Halland, Sweden, and the Swedish Dental Society.
Multivariate analysis of risk factors in relation to TMD symptoms
Authors: YATANI H. , HATANAKA K. , MATSUKA Y. , MINAKUCHI H. , TOMONARI T. 
Published: March 2003

The epidemiological studies on risk factors for temporomandibular disorders (TMD) are still extremely lacking. Therefore, their aetiological significance has scarcely been documented. The aim of this study was to quantitatively investigate the relationship between hypothesized risk factors and the precipitation and perpetuation of TMD symptoms.The same 672 adults who participated in a previous study (Matsuka et al., 1996) were selected for this study. All subjects had already answered a self‐administered questionnaire and the same questionnaire was sent to them 4 years after the first survey. The questionnaire failed to reach 58 subjects at the second survey. Of the remaining 614 subjects, 367 (166 males and 201 females with a mean age of 53·1 ± 14·2 years) returned the questionnaire, for a return rate of 59·8%. Information about three TMD symptoms [temporomandibular joint (TMJ) pain, limitation of mouth opening, TMJ noise] was obtained from the questionnaire, and fluctuation of these symptoms was assessed by comparing three pairs of answers between the first and second surveys. Information about 18 hypothesized risk factors for TMD (age, sex, trauma, bruxism, malocclusion, oral habit, etc.) were also obtained from the questionnaire at the first survey. To evaluate how strongly each risk factor was associated with precipitation and perpetuation of TMD symptoms, odds ratio of each risk factors for precipitating or perpetuating TMD symptoms was calculated by means of logistic regression analysis. Statistically significant risk factors for precipitating TMD symptoms were lip biting for TMJ pain (3·65) and trauma for limitation of mouth opening (3·20), and statistically significant risk factors for perpetuating TMD symptoms were female for TMJ pain (4·50) and TMJ noise (3·85) (odds ratio in parenthesis). The possible aetiological significance of these factors in TMD should be validated by future research.
Deformation/displacement of posterior digastric and sternocleidomastoid muscles during posterior digastric muscle palpation using magnetic resonance imaging and image processing procedure
Authors: SATO H. , MATSUGUMA T. , ISHIKAWA M. , KURAMOTO S. , UKON S. , ZEZE R. , KODAMA J. 
Published: March 2003

Objective: As the process of palpation is basically subjective, the scientific evidence for masticatory muscle palpation, especially from an anatomical point of view, is scarce. Our previous study concerning the quantification of masseter muscle deformation during palpation using magnetic resonance imaging and image analysis procedure showed that masseter muscles are deformed and their fascia must be stretched during palpation (Ishikawa et al., Int J Prosthodont, in press). The aim of this study was to further evaluate the deformation/displacement of posterior digastric and sternocleidomastoid muscles during posterior digastric muscle palpation using almost the same procedure as in the previous study. Subjects and methods: Subjects were 10 male volunteers with an average age of 26·8 years. MR images were taken using a 1·5 T scanner (MAGNEX 150 SHIMAZU Co. Ltd, Kyoto, Japan). Images were obtained on the axial plane with a spin‐echo, T1‐weighted technique using a head coil. At first, non‐compressed condition (control) was taken, then the continuously compressed condition of the bilateral posterior digastric muscle region using round plastic balls was taken. By superimposing a compressed image on a non‐compressed image, deformation/displacement was subjectively evaluated and measured using free image analysing software (NIH‐image). Results and conclusion: Deformation of the bilateral posterior digastric muscle was difficult to identify, however, the average amount of displacement in medial direction was 9·0 ± 5·3 mm. Although we tried to compress posterior digastric muscles, sternocleidomastoid muscles were additionally deformed and displaced. The amount of medial displacement was 9·3 ± 4·7 mm. The values contained in our results exhibited fairly substantial variance. These findings suggest that masticatory muscle palpation is subjective and inconsistent.