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PubMedDate not supplied

Development and application of reflexodent in the quantitative functional evaluation of chewing control in patients with temporomandibular joint dysfunction and a control group.

BACKGROUND: There has been controversy with respect to the diagnostic value of the inhibitory masseteric reflex in temporomandibular joint dysfunction (TMJD) because the whole reflex response was not considered. The purpose of this study was to characterize the reflex changes that occur in patients with different levels of TMJD and in a control group. METHODS: Eighty-nine patients (ages 31.14 +/- 12.74 years) divided into three groups were studied and compared. The control group was without TMJD (n = 30), with moderate symptoms (n = 30), and with severe symptoms (n = 29). Using an instrument and a software program developed by our group (Reflexodent), the masseteric inhibitory reflex was studied. The electromyography record (EMG) was captured with surface electrodes and the inhibitory reflex was produced by tapping the chin. The EMG signal was processed, filtered, and averaged with the Reflexodent. Twenty series of records were applied to each patient. The faulty inhibitory area, the area's relation (potentiation/inhibition) regarding the values of healthy subjects previously characterized, and the bilateral symmetry were measured. RESULTS: Discriminate analysis showed a statistically significant correlation between clinical groups and electromyographic findings. Statistical function explained 91.8% of the discrimination among groups (canonical correlation = 0.918, chi(2) = 164.435, p <0.001). CONCLUSIONS: The study of whole inhibitory masseteric reflex and the Reflexodent technique are useful as a diagnostic tool to evaluate TMJ illness in the dental clinic.

Adult↗
PubMed2000

From deception trials to control reagents. The introduction of the control group about a century ago.

This is the story of the remarkable psychologist John E. Coover, who, in the early 1900s, was the first to advocate the comparison of experimental and control groups as a methodological necessity. Moreover, the author raises the issue of why control groups were launched about a century ago, and why psychology was comparatively early in codifying group comparison as a methodological routine. In dealing with these questions, the author discusses the relations between turn-of-the-century science and society as well as between psychophysical research and educational experimentation. Furthermore, the mystery is solved of how Coover's rightful place in the received history of experimental controls could be taken by precisely the authors whom he criticized for the lack of controls.

Faculty↗
PubMed2006

Different interference effects in musicians and a control group.

In the present study musicians and normal control subjects performed an S1-S2 pitch comparison task, which included the presentation of intervening tones during the retention interval. The time for encoding and storing the pitch of S1 was varied between 200 and 1,500 ms by changing the pause between the S1 offset and the onset of the intervening tones. Although musicians outperformed the control group with longer pauses after the S1 offset, this advantage was relatively small with shorter pauses. These results suggest that the advantage of musicians in storing auditory information is not solely due to their superior encoding of information but also to improved working memory operations.

Adolescent↗
PubMed1978

Psychiatric evaluation of youth with cleft lip-palate matched with a control group.

Ten subjects were randomly selected from each of four pools of patients (male CPO, male CLP, female CPO and CLP) age six to 18 years regularly followed by a cleft palate clinic. Forty controls from a family practice clinic were matched for age, sex, and socio-economic status. Congenital second anomalies were present in 13 cleft children, five of whom were male CPO. Significant hearing loss was found in 11 cleft children and speech articulation problems in about 50 per cent of the sample. Both cleft and control groups were interviewed by a child psychiatrist, and mothers completed a behavior rating check list. There were no significant differences in the number of subjects from both groups having psychiatric diagnoses or conflicts. Mother's ratings indicated that cleft group had significantly more subjects with excessive dependency problems while control group had significantly more subjects having problems with resenting correction, talking negatively about self, and projecting blame to others. Significantly more male CPO and female CLP patients had psychiatric diagnoses, particularly mental retardation and developmental deviations, when compared to male CLP and female CPO groups. Cleft children with articulation problems were more likely to have psychiatric diagnoses and conflicts.

Abnormalities, Multiple↗
PubMed1982

Assessment of the use of the age- and sex-specific United States population as a control group for analysis of survival in coronary artery disease.

The use of the age- and sex-specific U.S. population as a control group for analysis of survival in coronary artery disease was assessed. Population-based survival rates were calculated for nonsurgically treated patients evaluated for coronary artery disease at Duke University Medical Center. Survival of the overall group of medically treated patients with significant coronary artery disease was lower than the corresponding age- and sex-specific U.S. population rates. However, survival of patients with significant disease who had normal left ventricular contraction and stable chest pain was similar to the age- and sex-specific population survival rates. Both the observed survival and the population-based survival estimates for patients with normal left ventricular contraction and stable pain were lower than the survival of patients with normal coronary arteriograms. Even after deaths from ischemic heart disease are eliminated from the population rates, survival of patients with normal coronary arteries exceeded the age-and sex-specific population survival. Because of biases inherent in the selection of patients for cardiac catheterization and the presence of other serious diseases in persons in the general population is not an adequate control group for rigorous analysis of the effect of therapy in coronary artery disease.

Actuarial Analysis↗
PubMed2005

The relationship between somatic and emotional stimuli: a comparison between adolescents with temporomandibular disorders (TMD) and a control group.

The overall purpose of this study was to determine whether adolescents with chronic temporomandibular disorder (TMD) pain are more sensitive to all types of somatic and emotional stimuli compared with a matched healthy control group. Sixty adolescents, 8 boys and 52 girls ranging from 12 to 18 years, participated in the study. Thirty of the subjects exhibited TMD, reporting pain of at least 3 months duration. The age- and gender-matched control group consisted of 30 dental recall patients who reported TMD pain less than once a week. All participants completed a 40-item questionnaire comprising 10 items each of pleasant and aversive qualities crossed with somatic and emotional forms of stimuli. The items, a selection of a broad range of familiar stimuli by a panel of experts, were rated based on intensity of experience (0-10, numerical rating scale). Well-fitting items that formed a valid construct within each of the four domains were selected using Rasch analysis. The results showed that adolescents with TMD pain reported significantly greater sensitivity (p<0.05) to aversive somatic and pleasant somatic stimuli than the controls. The differences between groups for the aversive emotional and pleasant emotional stimuli were non-significant. These findings suggest that chronic TMD pain states in adolescents are accompanied by amplification of bodily, but not purely emotional stimuli and that cognitive systems are implicated, not only an alteration of the nociceptive systems.

Adolescent↗
PubMed2002

Vibrotactile sense and mechanical functional state of the arm and hand among computer users compared with a control group.

OBJECTIVES: To measure sensory perception and mechanical muscle function of the arm among experienced female computer users with (+sPC) and without (-sPC) symptoms compared with a control group (ctrl). METHODS: Group +sPC had severe symptoms in the hand/wrist and/or the forearm/elbow region. They worked with the computer 75% and used a computer mouse 50% of the working day. Group -sPC had no or minimal symptoms. They used the computer 80% and a computer mouse 58% of the working day. The control group had no symptoms and worked with the computer for 2 h or fewer per day. Sensory perception threshold was measured using vibrotactilometry at five sites on the right hand representing nn. medianus, ulnaris and radialis. Mechanical muscle function was assessed by measuring muscle strength, wrist extension endurance, hand-eye co-ordination, and range of motion. Furthermore, performance was measured during standardized computer work. RESULTS: The perception thresholds for +sPC were greater in the areas innervated by n. medianus and n. ulnaris than for non-symptomatic groups, indicating that nerve compression is involved. For n. radialis, no differences were found between groups. No difference in isometric muscle strength was found for hand-grip, wrist extension, vertical pinch-grip and knee extension. However, for horizontal pinch-grip (pronated forearm) lower values were obtained for the +sPC group than for non-symptomatic groups. At the end of the endurance task, the perceived exertion was highest for +sPC. Furthermore, slower recovery was found for +sPC. No differences in range of motion, hand-eye co-ordination, and error rate during computer work were found between groups. CONCLUSIONS: Increased perception threshold values indicating entrapment of n. medianus and n. ulnaris were found for +sPC. Only few differences in mechanical muscle performance were found among the groups. The +sPC group had lower pinch-grip strength when measured in the pronated hand position, and the results indicated shorter muscle endurance for +sPC than for -sPC and ctrl.

Adult↗
PubMed1998

Control group characteristics and study outcomes: empirical data from a study on mortality of patients with type 2 diabetes mellitus in Dutch general practice.

STUDY OBJECTIVE: Control group characteristics as comorbidity and chronic psychosocial problems may play an important part in study outcomes. A primary care data base was used to quantify the effects of varying the case mix of participants. DESIGN: Historical cohort study. SETTING: Data were collected from 1967-1996 in four Dutch general practices performing the Continuous Morbidity Registration Nijmegen. PATIENTS AND CONTROLS: All newly diagnosed type 2 diabetic patients in the period 1967-1989 fulfilling the WHO criteria (n = 265); for each type 2 diabetic patient a control was matched for practice, sex, age, and social class; from these controls subgroups were selected based on the absence of different types of morbidity; these subgroups were also matched for practice, sex, age, and social class. MAIN RESULTS: The relative risk of mortality in type 2 diabetic patients in comparison with various subsets of controls ranged from 1.33 (95% CI 0.97, 1.81) to 2.16 (95% CI 1.46, 3.20). CONCLUSION: Control group characteristics as comorbidity and chronic psychosocial problems turned out to influence the risk estimation in a cohort study. General practice data enhance the study of these aspects.

Cardiovascular Diseases↗
PubMed1988

An ELISA for IgA-IgG and IgM-RF measurement. II. RF in several disease and control groups and under gold therapy in RA.

The before introduced solid phase ELISA was employed for the RF determination in the sera of RA patients and controls. The threshold values for positive results (calculated as the 95% distribution percentile of healthy donors) were 8, 3, and 3 U/ml for IgA, IgG, and IgM-RF, respectively. The results confirm the validity of the assay with clear negative results in several negative control groups (healthy donors, patients of the oto-, rhino-, laryngeal ambulance, diabetes mellitus, degenerative arthropathies; n = 111, median IgA, IgG and IgM-RF values of less than or equal to 2, less than or equal to 2 and less than or equal to 1 U/ml, respectively; 25-75% distribution percentiles within the median value) and positive results in the positive control group (seropositive RA; n = 20, median IgA, IgG and IgM-RF values of 324, 479 and 170 U/ml, respectively). 16/24 patients with so-called seronegative RA (negative Latex Fixation Test or Waaler Rose Test) had positive results in the ELISA, two of them had rheumatoid nodules clinically. The IgG-RF activity in the ELISA appears to be a good parameter for the course control of RA under gold therapy. 10 RA patients with clinical improvement of disease (declining ESR, CRP, joint index) after six months of gold therapy (= 0.6 g total gold amount) had a decline of total RF activity of 70% in median, whereas 10 patients with no clear effect on disease activity had only a decline of 20% in median.

Arthritis, Rheumatoid↗
PubMed1987

[Treatment of progressive and severe forms of multiple sclerosis using a combination of antilymphocyte serum, azathioprine and prednisone. Clinical and biological results. Comparison with a control group treated with azathioprine and prednisone only. 4-year follow-up].

45 patients were treated by combined application of antilymphocyte serum, azathioprine and prednisone: a control group of such 22 patients was besides treated by azathioprine and prednisone only. The treatment by antilymphocyte serum included a four weeks initial treatment, and one year continuous treatment one infusion per week. Azathioprine and prednisone were given every day during the same time. Azathioprine only was given during the three following year. The two groups were followed up during four years. This treatment was well accepted by patients under strict technical survey conditions. Serum sickness was noted in 11 p. cent of the cases. The equine antiglobulin antibody titre, increased during the initial treatment, was connected with serum sickness or, when the treatment was continued, with the inefficacy of the treatment. Rosettes titre decreased in ten cases, no clinical correlation was possible. The complement, immune complexes, were normal before treatment with most of the observed patients. The delayed hypersensitivity skin tests were negative after a month in 80 p. cent of the cases. The cerebrospinal fluid analysis, for the elements as well as for the rate of proteins and gammaglobulins, showed no significant variations before and after the treatment. The comparison with the control group showed a significant statistical difference as too the number of aggravated and improved patients after the first year. When grouping together stable and improved patients, the difference was statistically significant after the third year. The difference was not significant in years "two" or four. No difference in the frequency of the relapses could be noted, in the first year or the following three years. In spite of inconsistent results comparison showed favorable data after three years. The good results seemed due to the additional use of antilymphocyte serum. Such a treatment associating antilymphocyte serum to azathioprine and prednisone is beneficial in evolutive, remittent and recent multiple sclerosis. Through the length of the treatment remains difficult to determine, we conclude that it is really beneficial for such patients.

Antilymphocyte Serum↗
PubMed1995

Auditory event-related brain potentials in autistic children and three different control groups.

ERPs to auditory stimuli, generated during an oddball task, were obtained in a group of autistic children and three control groups (normal, ADDH, and dyslectic children, respectively). The task included the presentation of standards, deviants, and novels and had a (between-group) passive vs. active (counting) condition. It was examined whether 1) it was possible to replicate several earlier findings, 2) autistics manifest an abnormal lateralization pattern of ERPs, 3) autistics have an abnormal mismatch negativity (MMN), and 4) differences between autistics and normals are really specific to the autistic group. The only finding that could be replicated was that autistics have a smaller A/Pcz/300. There was no evidence for abnormal lateralization or abnormal MMN; however, there was an unexpected effect of the task manipulation on the amplitude of the P3: in autistics, the occipital P3 to deviant stimuli was significantly larger in the active than in the passive condition, a finding, like the replication of the smaller A/Pcz/300, specific to the autistic group. It was suggested that the auditory occipital task effect is related to understimulation of the occipital lobe by visual stimuli in autistic children.

Adolescent↗
PubMed1986

Association of endometriosis and spontaneous abortion: effect of control group selection.

Endometriosis has been associated with an increased incidence of spontaneous abortion, compared with the abortion rate of the general population. To assess whether a separate control group would affect these conclusions, we studied 139 consecutive infertility patients with laparoscopically proven endometriosis to determine the incidence of spontaneous abortion. Ninety-five of these patients underwent conservative surgical resection of endometriosis, and 44 patients opted for expectant management. There was no significant difference between these two groups in average age, duration of infertility, or proportion of patients with primary infertility. The average spontaneous abortion rate before diagnosis for all patients was 63.1%. After surgical treatment, the abortion rate dropped to 0% (P less than 0.000001) for all stages of disease. However, even in those patients who received expectant management only, the abortion rate fell to 16.7% and 21.4% for mild and moderate endometriosis, respectively (P less than 0.001). These results suggest that the spontaneous abortion rate in untreated endometriosis may not be as high as previously reported and may not be significantly different from the rate in the general population. The data also emphasize the need for well-defined control groups when assessing the effects of a treatment regimen.

Abortion, Spontaneous↗
PubMed1985

Anterior repositioning splint in the treatment of temporomandibular joints with reciprocal clicking: comparison with a flat occlusal splint and an untreated control group.

The anterior repositioning splint is widely used to treat temporomandibular joints with reciprocal clicking. This treatment was compared to a flat occlusal splint and to an untreated control group. The anterior repositioning splint decreased joint pain at rest, during chewing, and during protrusion. Reciprocal clicking was eliminated and palpatory tenderness of the joint and muscles was reduced. This favorable effect was of short duration. The majority of the patients reported pain and clicking and demonstrated tenderness following removal of the splint after 6 weeks' treatment. The flat occlusal splint decreased joint tenderness but did not affect clicking or muscle tenderness. In the control group the clicking remained and the frequency of muscle tenderness increased. The results indicate that temporomandibular joints with reciprocal clicking can be successfully treated by positioning the mandible anteriorly. Since the symptoms returned when the splint was removed a more permanent change of mandibular position seems necessary.

Adolescent↗
PubMed2000

Results of open meniscus repair. Long-term follow-up study with a matched uninjured control group.

We have followed for 13 years a consecutive series of 31 patients who had open repair of a torn meniscus. They were between 13 and 43 years of age at the time of operation and all had intact stabilising ligaments. Comparison was made with a matched group of normal subjects of similar age and level of activity. The total rate of failure after meniscal repair was 29%; three of the repaired menisci did not heal and six reruptured during the follow-up period. At follow-up 80% of the patients had normal knee function for daily activities. Radiological changes were found in seven. Two had reduction of the joint space (Ahlbäck grade 1), one with successful and one with failed repair. In the control group of uninjured subjects one knee showed Fairbank changes but none had changes according to Ahlbäck. The incidence of radiological changes did not differ between the group with meniscal repair and the control group but knee function was reduced after meniscal repair (p < 0.001). We conclude that the long-term results of meniscal repair in stable knees are good with nearly normal function and a low incidence of low-grade radiological changes.

Adolescent↗
PubMed1995

[Neurologic development in premature infants under 33 weeks of gestational age: determination of risk of neurological abnormalities in a prospective regional survey with a control group].

AIM: The purpose of this population-based study was to compare the incidence of neurodevelopmental disability and its risk factors between preterm and full-term infants matched as control group. POPULATION AND METHODS: The preterm cohort included 203 infants born between 25 and 33 weeks of gestational age in the region of Franche-Comté (France) during a two-year-period. The control group included 196 full-term infants born in the same maternities. Survival up to the date of follow-up was 171/203 (84%) for preterms and 195/196 (99.5%) for full-term infants (uncorrected age, mean 12 months). Neurodevelopmental assessments were performed by pediatricians or physicians on 164/171 surviving preterms (96% follow-up) and 179/195 full-terms (92%). RESULTS: Thirty-two (19.5%) preterm infants had disability, ten of these (6%) showing severe disability. Five (2.8%) full-term infants had disability, one of these (.5%) having severe disability. Risk factors predicting a disability included in a multivariate approach: prematurity (odds-ratio [OR]: 7.8), maternal age > 37 (OR: 3.0), lack of profession for both parents (OR: 3.7), male gender (OR: 2.9). The pediatrician observed a disability more frequently than the physician (OR: 2.46). Likewise, risk factors predicting a severe disability included: prematurity (OR: 10.8), lack of profession for both parents (OR: 5.8) and monochorial twin-placentation (OR: 4.5). CONCLUSIONS: Prematurity is not the only risk factor to be taken into account for neurodevelopmental evaluation of premature infants, but its influence still remains widely predominant.

Child Development↗
PubMed2006

[Mechanism of signal transduction of differentiation of mesenchymal stem cells into cytokeratin-expressing epidermoid cells].

OBJECTIVE: To investigate the role of the signal routes P38, ERK, and Rho in the differentiation of bone marrow mesenchymal stem cells (MSCs) into epidermoid cells. METHODS: (1) MSCs were separated from the bone marrow of Wistar rats by Ficoll-Pague lymphocyte separating medium and proliferated in culture medium. Then the MSCs were immunocytochemically stained to detect the expression of surface antigens. (2) The MSCs were randomly divided into 3 groups: control group; pure induction induced group, cultured with epithelial growth factor (EGF) added into the culture fluid, and Rho inhibition group, cultured with EGF and HA1077, a ROK inhibitor, added into the culture fluid. One, 3, 5, and 7 days later FC was used to detect the levels of phosphorylated P38 and ERK. (3) MSCs were randomly divided into 4 groups: control group, cultured with low-sugar DMEM complete culture fluid; pure induction group, cultured with supernatant of rat fibroblasts and EGF added into the culture fluid, p38 blocking group, with SB203580, inhibitor of P38 added into the culture fluid; and ERK blocking group, with PD98059, inhibitor of ERK added into the culture fluid. Seven days later, SP method was used to detect the expression of CK5/8 and CK19 induced by MSCs. (4) MSCs were randomly divided into 4 groups: control group; pure induction group, with supernatant of rat fibroblasts and EGF added into the culture fluid; and RHO blocking group, with HA1007 added into the culture fluid. Seven days later, FC was used to detect the expression of CK5/8 and CK19. RESULTS: (1) Both FC and immunocytochemistry showed that the MSCs were uniformly positive in CD29 and CD44, but did not express CD34 and CD45. (2) The phosphorylated P38 rate remained 0.01% in the control group. The phosphorylated P38 rate was 0.04%, significantly higher than that of the control group (0.01%, P < 0.05) at day 5, and then lowered to 0.01% at day 5 in the pure induction group; and became 6.17%, 4.13%, 3.97%, and 0.41% respectively at day 1, 3, 5, and 7, all significantly higher than those of the control group (all P < 0.05), in the Rho inhibition group. The phosphorylated ERK level was 4.23% in the control group; became 0.39% and 0.40% at day 3 and day 5 (both P < 0.05), and then returned to 5.10% at day 7 in the pure induction group; and was not significantly changed at days 1, 3, and 5, and then became 0.41%, significantly lower than that of the control group (P < 0.05), in the Rho blocking group, (3) The control group was CK5/8 and CK19 negative. The CK5/8 and CK19 rates at day 7 of the pure induction group were 3.01% and 6.47% respectively, both significantly higher than those of the p38 inhibition group (1.43% and 5.41% respectively, both P < 0.05). The CK5/8 and CK19 expression rates of the ERK inhibition group were 5.54% and 7.56% respectively, both significantly higher than those of the pure induction group (both P < 0.05), (4) The CK5/8 and CK19 expression rates of the HA1077 group were 21.65% and 39.41% pure, both significantly higher than those of the pure induction group (1.81% and 10.19% respectively, both P < 0.05). CONCLUSION: p38 route may play an active role in the differentiation of MSCs into epidermoid cells. Blocking of the upstream signal Rho may enhance the activation of p38 route and then promote the differentiation of MSCs into epidermoid cells.

1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine↗