Subject Tolerance Research Articles

Разработка и апробация опросника диспозиционной терпимости личности

<p>Objective of the work was to construct and validate a dispositional tolerance questionnaire that aims to measure the subject's tolerance level in a complex way. Data collection was carried out in an online format. The methodology was approved with 160 students, the average age was 20 years old. In order to validate the presented questionnaire of dispositional tolerance we used methods of internal coherence and reliability of the scale, convergent validity, as well as confirmatory factor analysis to check the compliance of the theoretical factor structure of the questionnaire with the real one. Internal consistency of the methodology was assessed by calculating the value of Cronbach's α coefficients = 0.725. Convergent validity was assessed with the tolerance index questionnaire and the correlation level was 0.601. Factor analysis of the dispositional tolerance questionnaire confirmed the factor structure of the methodology. The meaning of dispositional tolerance was conceptualized and compared with existing concepts of psychological tolerance for further presentation of the psychometric instrument. This questionnaire stands as a method to diagnose tolerance as a subject's attitude. The obtained results confirmed sufficient reliability for using the presented psychometric tool in psychological practice.</p>

A Dermocosmetic Significantly Reduces the Frequency and Intensity of Facial Skin Intolerability and Sensitivity in Subjects with Skin Intolerant to Skin Care Products and Sensitive Skin.

Intolerance to dermocosmetics is frequent in subjects with allergic contact dermatitis (ACD). A dermocosmetic (DC) was developed to restore the natural skin barrier, to reduce skin inflammation and to improve sensitive skin in ACD. To assess the benefit of a DC in subjects with an allergic background and intolerance to cosmetic care, or with sensitive skin. In this open-label study, 107 subjects above 16 years of age applied DC on the face twice a day for 28 days. Assessments at Days 0, 14 and 28, included skin sensitivity, stinging test, local tolerance, transepidermal water loss (TEWL), skin hydration, inflammatory biomarkers (IL-1α, IL-1RA, PGE2) using tape stripping and subject satisfaction. 88% were women and mean age was 42.0±15.0 years. Skin sensitivity at inclusion scored 5.9±0.35; 46% had ACD, 95% skin irritation, 92% sensitive skin and 88% intolerance to cosmetics. A significant (p<0.0001) 85% decrease of frequency and intensity of the composite score was observed at both endpoints. Stinging scores significantly (p<0.0001) decreased from 3.9 at baseline to 2.4 at Day 14 and 1.4 at Day 28; 77% and 81% of subjects reported improved skin reactivity at Day 14 and Day 28, respectively. Similar improvements were noted in the frequency and intensity of irritation, erythema, stinging, burning and discomfort. TEWL, skin hydration and inflammatory biomarker levels significantly (p<0.0001) improved. Overall subject satisfaction (85%) and tolerance (investigators: 99%, subjects: 97%) were high. DC significantly reduced the frequency and intensity of facial skin intolerability and sensitivity in subjects with skin intolerant to skin care products. NCT05487937.

Comparison of ocular surface assessment and adherence between preserved and preservative-free latanoprost in glaucoma: a parallel-grouped randomized trial

Given that nonadherence is related to subject characteristics and drug tolerance and preserved eye drops tend to be more intolerable than preservative-free ones, we conducted a phase 4, parallel-grouped, investigator-blind, active-control, randomized, multicenter study. A total of 51 patients with intraocular pressure (IOP) ≥ 15 mmHg diagnosed with open-angle glaucoma or ocular hypertension were randomly assigned to the preserved latanoprost group (n = 26) and the preservative-free latanoprost group (n = 25). The efficacy variables were corneal/conjunctival staining grade, Ocular Surface Disease Index (OSDI), adherence at 12 weeks after the first administration; corneal/conjunctival staining grade at 4 weeks; and IOP, tear break-up time (TBUT), and hyperemia score at 4 and 12 weeks. The safety variables included visual acuity and drug tolerance questionnaire results. There was no statistically significant difference in corneal/conjunctival staining grade, OSDI, or TBUT between the groups at 4 and 12 weeks. However, the adherence rate was higher and the hyperemia score was lower in the preservative-free group than in the preserved group. The severity and duration of stinging/burning sensation were lower in the preservative-free group than in the preserved group. Overall, preservative-free latanoprost showed better ocular tolerance assessed by hyperemia scores and stinging/burning symptoms following higher adherence than preserved latanoprost.

A size-adaptive 32-channel array coil for awake infant neuroimaging at 3Tesla MRI.

Functional magnetic resonance imaging (fMRI) during infancy poses challenges due to practical, methodological, and analytical considerations. The aim of this study was to implement a hardware-related approach to increase subject compliance for fMRI involving awake infants. To accomplish this, we designed, constructed, and evaluated an adaptive 32-channel array coil. To allow imaging with a close-fitting head array coil for infants aged 1-18 months, an adjustable head coil concept was developed. The coil setup facilitates a half-seated scanning position to improve the infant's overall scan compliance. Earmuff compartments are integrated directly into the coil housing to enable the usage of sound protection without losing a snug fit of the coil around the infant's head. The constructed array coil was evaluated from phantom data using bench-level metrics, signal-to-noise ratio (SNR) performances, and accelerated imaging capabilities for both in-plane and simultaneous multislice (SMS) reconstruction methodologies. Furthermore, preliminary fMRI data were acquired to evaluate the in vivo coil performance. Phantom data showed a 2.7-fold SNR increase on average when compared with a commercially available 32-channel head coil. At the center and periphery regions of the infant head phantom, the SNR gains were measured to be 1.25-fold and 3-fold, respectively. The infant coil further showed favorable encoding capabilities for undersampled k-space reconstruction methods and SMS techniques. An infant-friendly head coil array was developed to improve sensitivity, spatial resolution, accelerated encoding, motion insensitivity, and subject tolerance in pediatric MRI. The adaptive 32-channel array coil is well-suited for fMRI acquisitions in awake infants.

Changes in Symptoms of Midday Fogging with a Novel Scleral Contact Lens Filling Solution.

SIGNIFICANCEMidday fogging of scleral contact lenses requires frequent lens removal and reapplication for a large portion of lens wearers. Using a lens filling solution that mimics the composition of tears is hypothesized to have an impact on the production of material trapped under a scleral lens.PURPOSEThe purposes of this open-label study were to assess the safety of a scleral lens filling solution, which closely approximates the ionic concentration and pH of human tears, and to assess signs and symptoms of midday fogging with this formulation and with subjects' habitual sodium chloride solutions.METHODSExisting scleral lens wearers with midday fogging (N = 22) were examined and completed surveys of symptoms. Subjects filled the concavity of their current lenses with test solution and were assessed immediately and approximately 4 hours later for safety monitoring. Test solution was dispensed and used for 5 to 9 days when subjects were reexamined and repeated the surveys. Biomicroscopy and anterior optical coherence tomography images were used to assess midday fogging objectively.RESULTSThe median (interquartile range) Ocular Surface Disease Index score decreased from 27.1 (21.7) U when using habitual filling solution to 9.1 (20.1) U when using the test solution (P = .006). Current Symptoms Survey findings with the test solution compared with habitual solution resulted in statistically significant decreases in burning/stinging (P = .04), grittiness/foreign body sensation (P = .01), dryness (P = .002), blurry/fluctuating vision (P = .002), and overall pain/discomfort (P = .006). Objective assessment of corneal staining and fogging revealed decreases that were not statistically significant in this small sample size.CONCLUSIONSThis study establishes the safety and subject tolerance of a scleral lens filling solution that mimics the ionic composition of human tears. Significant improvements in subjective ratings, although likely biased in this unmasked trial, suggest that further studies of the effectiveness of this solution in reducing midday fogging are warranted.

A Randomized Trial of Modified-Release Versus Immediate-Release Tolvaptan in ADPKD

IntroductionTolvaptan, for treatment of autosomal dominant polycystic kidney disease (ADPKD), is provided as immediate-release (IR) tablets administered twice daily in split-dose regimens to suppress urine osmolality to <300 mOsm/kg. A modified-release (MR) formulation was developed for once-daily (QD) dosing to increase compliance and mitigate urinary symptom burden. This phase 2, dose-ranging study (NCT01210560) compared pharmacokinetics, pharmacodynamics, and tolerability of several MR regimens with IR in patients with ADPKD.MethodsThis was a multicenter, parallel-arm, randomized, crossover, double-blind, placebo-controlled trial. Each of 2 study arms had 12 subjects and 3 crossover periods. Dose regimens were administered for 7 days; placebo-masked QD versus split-dose treatments. Endpoints included pharmacokinetic parameters, percentage of subjects with urine osmolality <300 mOsm/kg, urine volume, number of daily urine voids, and tolerability.ResultsTolvaptan MR 20 to 120 mg exhibited dose-proportional pharmacokinetics. Percentage of subjects with spot urine osmolality <300 mOsm/kg increased with dose, with tolvaptan MR 120 mg and IR 90+30 mg each suppressing 91.7% of subjects below this level. Urinary burden on the ADPKD Nocturia Quality of Life, ADPKD Urinary Urgency, and ADPKD Urinary Frequency Questionnaires correlated with tolvaptan exposure, with high interindividual variability in responses. Changes in questionnaire scores were sensitive to changes in urine volume but not proportional to volume change, reflecting differences in subject tolerance to increased urine volume.ConclusionTolvaptan MR exhibited predictable and dose-proportional pharmacokinetics and no improvement in tolerability versus tolvaptan IR. Tolerability of the urinary effects of treatment within the high-dose MR and IR groups exhibited substantial interindividual variability.

Noninvasive Ventilation as an Important Adjunct to an Exercise Training Program in Subjects With Moderate to Severe COPD.

The primary objective of this study was to investigate whether noninvasive ventilation (NIV) can positively affect exercise capacity, maximum oxygen uptake (V̇O2 ), and symptoms after a 6-week physical training program for subjects with moderate to very severe COPD. 47 subjects with COPD who were enrolled in a physical training program were randomized to either physical training alone or NIV + physical training (NIV-Physical training). Physical training consisted of dynamic aerobic exercises on a treadmill 3 times/week for 6 weeks, for a total of 18 sessions. NIV was titrated according to the subject's tolerance at rest and during exercise. Assessments included physiological responses and symptoms at the incremental cardiopulmonary exercise test peak and during submaximal exercise on a treadmill, 6-min walk distance, maximum inspiratory (PImax) and expiratory pressure (PEmax), BODE index, and health-related quality of life. 43 subjects completed the 6-week physical training program. Both groups improved 6-min walk distance, PImax, BODE index, and quality of life, and no differences were found between groups. However, significant improvements were observed for subjects in the NIV-Physical training group with regard to PEmax, maximum V̇O2 , maximum metabolic equivalents, circulatory power, and maximum SpO2 . A 6-week physical training program alone can improve tolerance for exercise and quality of life, in addition to reducing the risk of mortality. However, NIV associated with a physical training program was shown to have an additive beneficial effect on powerful prognostic markers (maximum V̇O2 and circulatory power) and to reduce symptoms and improve oxygen saturation in subjects with moderate to very severe COPD.

THE EFFECTS OF BLOOD FLOW RESTRICTION TRAINING ON FUNCTIONAL IMPROVEMENTS IN AN ACTIVE SINGLE SUBJECT WITH PARKINSON DISEASE

Blood flow restriction (BFR) applied during low intensity exercise produces hypertrophy and strength gains equivalent to traditional training. Previous research has shown the positive effects of BFR on younger and older adults. However, the effectiveness of BFR on subjects with Parkinson Disease (PD) has not been investigated. The purpose of the study was to determine the effects of BFR on a recreationally active person with PD in regards to functional improvements and safety. The hypothesis was that BFR training will demonstrate improvements in motor function, gait and endurance, while decreasing symptoms associated with Restless Leg Syndrome (RLS) in a subject with PD. A single subject, B-A design was used. The subject was an active 65-year-old male recreational boxer diagnosed with PD. Baseline data were measured on day one. The intervention (Phase B) consisted of five, two-minute bouts of walking on treadmill with lower extremity BFR cuffs interspersed with 1 minute rest, three times a week for six weeks, at 0 grade incline, and speed of 50 meters/min. The pressure increased from the initial 120 to 160 mmHg at the end of the phase B as per the subject's tolerance. A four-week baseline phase (A) without the BFR intervention followed phase B. The outcome measures which were measured every two weeks over the 10 weeks included: Timed Up and Go Test, 6-Minute Walk Test, 30-Second Chair Stand Test, and the RLS Questionnaire. All outcome measures steadily improved every two weeks during the six week intervention phase and steadily declined when the intervention was removed during the second four week baseline phase according to visual inspection of the graphed data points. The subject enjoyed and tolerated the intervention well without any adverse effects. The results were that BFR training can produce functional improvements, reduce restless leg syndrome symptoms and can be safely utilized with a subject with PD who wishes to maintain his ability to remain recreationally active.

The effects of traditional strengthening exercises versus functional task training on pain, balance and functional mobility in knee osteoarthritis

The effects of traditional strengthening exercises versus functional task training on pain, balance and functional mobility in knee osteoarthritis Krishna Kumar Singh*, Madhusudan Tiwari** *Professor & Principal, Jaipur Physiotherapy College, Maharaj Vinayak Global University, Jaipur Rajasthan, India. **Associate Professor & Dean, Faculty of Physiotherapy, Mahatma Gandhi University of Medical Sciences & Technology, Jaipur, Rajasthan, India. Email- madhusudan1977@gmail.com, Mobile No. – 8290964159, (Corresponding Author). ABSTRACT Objectives: To investigate the efficacy of functional task training in decreasing pain, and increasing functional mobility in Osteoarthritis Knee. Study design: Comparative case control study. Methodology: Forty individuals with a diagnosis of OA Knee were selected directly from Physiotherapy outpatient door of Jaipur Physiotherapy College, MVGU, Jaipur. These individuals were randomly assigned into two groups: FTT Group [Functional task Training (n = 20)] and TE Group [Traditional Exercise (n = 20)]. FTT Group Functional tasks included sit to stand box lift, standing star exercise, walking up and down a ramp while holding a weight, ascending/descending stairs while holding a weight in the preferred hand, and walking indoors while passing a weighted ball from hand to hand. Subjects performed the exercises for one minute with (when indicated) a one pound weight. Progressions included either an increase in weight or time to perform the activity. Subjects in the TE program performed four-way straight leg raises (4 way SLR), seated knee extension, wall slides, step ups, and ambulation on the treadmill. Two sets of ten repetitions were performed for each exercise. Weight repetition progression based on subject's tolerance. Subjects ambulated on the treadmill at their own pace for a period that did not exceed 15 minutes. Both the groups were given exercises supervised by physiotherapist on regular basis for 12 weeks. Data for measurements of pain on VAS scale, Physical Function on WOMAC, Balance & mobility on Time Up & Go Test (TUG), Functional performance on Stair Climbing test (SCT) was collected on day 1 (pre treatment session), at 6 week, and at week 12. Results: Results indicate that both groups improved in all measures of pain, Balance and functional outcomes. However upon Intergroup analysis the mean changes in the score of VAS, WOMAC & TUG was highly significant across the two testing periods (at 6 week & 12 week) for the functional task training group (FTT). The mean change in the score of SCT was also highly significant at week 12 in FTT group. Conclusion: Functional task training on regular basis is an effective rehabilitation program for improving functional mobility, balance and decreasing pain in OA Knee. Key words: Functional Task Training, Traditional exercises, OA Knee, visual analogue scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)

Tolerance of the VocaLog™ Vocal Monitor by Healthy Persons and Individuals With Parkinson Disease

To assess subject tolerance of extended use of the VocaLog™ vocal monitor (VM), a device marketed to log calibrated decibel sound pressure level. Prospective between-subjects design including two age- and sex-matched groups: individuals with Parkinson disease (IWPD) and healthy persons. After an initial session to calibrate the device and demonstrate its use, participants wore the VM during waking hours for five consecutive days. At a second visit to return the VM, participants completed a survey and a short interview regarding their experience with and perceptions of the device. Those with PD and control subjects reported relatively few issues with use of the VM. There were no group differences regarding convenience, others' reactions, technical issues, or future participation in similar studies. Participants with PD indicated similar frequency of discomfort issues but higher severity ratings for discomfort during VM use compared with healthy participants. The VocaLog™ offers a method to monitor vocal loudness during everyday activities for several consecutive days. The device was well tolerated by participants from both groups. IWPD reported greater discomfort than controls, possibly reflecting altered sensory perceptions associated with PD. The current data offer some reassurance that this VM can be tolerated by both healthy persons and those with PD for clinical and research purposes.

TOLERANCE PECULIARITIES OF SUBJECTS WITH DIFFERENT ETHNIC IDENTITY

The present Article dwells upon theoretical and empirical analyses of tolerance peculiarities of multicultural environment subjects with high and low ethnic identity. This paper presents the connection of tolerance and ethnic identity, which is a very topical problem of the modern society as the number of intercultural and social conflicts increases. Comparative and correlation analyses proved that ethnic identity is connected with subject's tolerance: the higher ethnic identity is, the higher tolerance is. It is proved that there are significant differences between the cognitive, affective and behavioral aspects of tolerance of subjects with high and low ethnic identity. The results of empirical analysis show that people with high ethnic identity are much more sure in “favour” of the world and kindness of people, the level of their psychological safety is higher, they are much more tolerant to people of other nationalities and have a very short social distance with them. These data are very important for establishing educational, correctional, cultural programs, aimed at forming positive tolerant life suggestions of people living in multicultural regions.

A Randomized Trial on Subject Tolerance and the Adverse Effects Associated With Higher- versus Lower-Flow Oxygen Through a Standard Nasal Cannula

Experts advocate the use of a standard nasal cannula to provide oxygen at flow rates of up to 15L/minute during emergency intubation. However, because of concerns about potential patient discomfort, some providers avoid providing nasal cannula oxygen at flow rates greater than 6 L/minute. This trial is designed to determine the participants' ability to tolerate 10 minutes of nasal cannula oxygen at higher flow rates. This was a prospective, randomized, crossover trial of healthy volunteers at an emergency department in New Zealand. Participants were randomized to first receive either higher-flow (15 L/minute) or lower-flow (6 L/minute) nasal cannula oxygen for 10 minutes. After a 1-hour washout period, they received the alternate flow rate for 10 minutes. The primary outcome was the ability to tolerate 10 minutes of the nasal cannula oxygen at each flow rate. The secondary outcome was the difference in discomfort between the flow rates as measured on a 100-mm visual analog scale. All 77 of the participants (100%) were able to tolerate 10 minutes at both flow rates. Participants rated the higher-flow nasal cannula oxygen as a mean of 25 mm (SD 20 mm) more uncomfortable than the lower-flow nasal cannula oxygen. One minute after the oxygen was discontinued, the mean difference in discomfort between the flow rates was a clinically insignificant 9.8 mm (SD 17 mm) more uncomfortable. There were no adverse events. Participants were able to tolerate higher-flow nasal cannula oxygen for 10 minutes without difficulty. Higher-flow nasal cannula oxygen at 15 L/minute was associated with some discomfort, but the discomfort quickly dissipated and caused no adverse events.

Side Impact PMHS Thoracic Response With Large-Volume Air Bag

Objective: The objective of this study is to assess the response of postmortem human subjects (PMHS) to a large-volume side air bag in a fully instrumented and well-controlled side impact test condition. Methods: Three adult male PMHS were subjected to right-side pure lateral impacts. Each stationary seated subject was struck at 4.3 ± 0.1 m/s by a rigid wall installed on a 1700-kg rail-mounted sled. Each subject was held stationary by a system of tethers until immediately prior to being impacted by the moving wall. A large side air bag was mounted to the wall and deployed so that it was fully inflated at the time it contacted the subject's right side. The load wall consisted of an adjustable matrix of 15 individual plates, each supported by a 5-axis load cell that recorded the interaction between the subject and impacting wall. Two-dimensional (external) torso deformation was provided by a chest band that encircled the torso at the level of the sixth rib laterally. Triaxial acceleration was measured at the head, spine, and sacrum via 3 orthogonal accelerometers mounted to the same bone-mounted hardware that held the marker clusters used for kinematic analysis. Results: Peak pelvic load normal to the wall averaged 6.8 kN, which was over 5 times that recorded for the shoulder (1.3 kN) and the thorax (1.2 kN). Lateral chest deflection ranged from 9 to 21 mm. Two of the 3 subjects sustained 2 and 9 fractures, respectively. Conclusions: Two of the 3 PMHS sustained rib fractures despite low levels of thorax deflection. We attribute this finding to individual variability in subject injury tolerance. Other response parameters exhibited lower levels of variability and characterize PMHS response to a potentially beneficial side impact countermeasure. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file.

Sham Manual Medicine Protocol for Cervical Strain-Counterstrain Research

To describe the development of a sham manual medicine protocol. An academic physical medicine and rehabilitation clinic. Twenty-six persons with cervical tender points were included in the pilot study. Exclusion criteria entailed cervical disk herniations or diskitis, cancer, current incarceration, or any condition that prevented small-range passive neck movements. Subjects were also excluded if, in the past 3 months, they had received cervical or thoracic spine surgery, osteopathic manipulation, or workers' compensation benefits. The subjects were sequentially assigned to receive either sham or strain-counterstrain treatment. The subjects filled out pre- and posttreatment questionnaires. Fifteen subjects were in the sham group, and 11 were in the treatment group. Outcome measures included subject tolerance of manual medicine, change in pain level, and ability to accurately determine receipt of strain-counterstrain or sham technique. Statistical significance was set at P < .05. There were no adverse effects of the sham or treatment protocols. There was no statistically significant change in pain as a result of the sham manual medicine protocol (P = .222) in contrast to the strain-counterstrain group, which did have decreased pain (P = .014). The subjects were unable to determine whether they had received sham or strain-counterstrain technique (P = .850). The sham protocol developed for this study was well tolerated. The small study size and design limitations do not yet allow the sham protocol developed in this pilot study to be definitively validated as a manual medicine tool, but there are early indications that it may be useful. Larger studies that validate this sham protocol by addressing inter- and intra-rater reliability are needed, followed by studies that evaluate strain-counterstrain as a treatment modality.

Subject tolerance of 7 T MRI examinations

To determine the subjective experiences and the sources of discomfort for subjects undergoing 7 T magnetic resonance imaging (MRI) examinations on a whole-body 7 T system in a hospital setting A postscan survey was filled out by 101 healthy subjects who participated in a 7 T examination. All participants answered questions regarding different potential sensations of discomfort including dizziness, claustrophobia, and scanner noise. Dizziness was reported most frequently, with 34% of subjects experiencing dizziness while moving into the scanner and 30% while moving out of the magnet. Scanner noise was also frequently mentioned as uncomfortable (33% of the subjects). In 11% of the cases a metallic taste was reported. The overall experience was rated by 3% as unpleasant, 51% as neutral, and 46% as pleasant. The reported side effects are larger than previously reported for lower field strengths. However, overall, 7 T examinations are well tolerated, with only 3% of subjects rating it as unpleasant. These results agree well with previous in-depth studies, and provide further evidence that 7 T MRI would be accepted by patients in clinical practice.

Development of a Neuromuscular Electrical Stimulation Protocol for Sprint Training

Sprint training is associated with several beneficial adaptations in skeletal muscle, including an enhancement of sarcoplasmic reticulum (SR) Ca(2+) release. Unfortunately, several patient populations (e.g., the elderly, those with cardiac dysfunction) that might derive great benefit from sprint exercise are unlikely to tolerate it. The purpose of this report was to describe the development of a tolerable neuromuscular electrical stimulation (NMES) protocol that induces skeletal muscle adaptations similar to those observed with sprint training. Our NMES protocol was modeled after a published sprint exercise protocol and used a novel electrode configuration and stimulation sequence to provide adequate training stimulus while maintaining subject tolerance. Nine young, healthy subjects (four men) began and completed the training protocol of the knee extensor muscles. All subjects completed the protocol, with ratings of discomfort far less than those reported in studies of traditional NMES. Training induced significant increases in SR Ca(2+) release and citrate synthase activity (~16% and 32%, respectively), but SR Ca(2+) uptake did not change. The percentage of myosin heavy chain IIx isoform was decreased significantly after training. At the whole muscle level, neither central activation nor maximum voluntary isometric contraction force were significantly altered, although isometric force did exhibit a trend toward an increase (~3%, P = 0.055). Surprisingly, the NMES training produced a significant increase in muscle cross-sectional area (~3%, P = 0.04). It seems that an appropriately designed NMES protocol can mimic many of the benefits of sprint exercise training, with a low overall time commitment and training volume. These findings suggest that NMES has the potential to bring the benefits of sprint exercise to individuals who are unable to tolerate traditional sprint training.

Impacts of the different tissue specificities of the acupoints on electroacupuncture sensations

ObjectiveTo evaluate the influence of the tissue specificity of the acupoints (different meridians, tissues and nerve segments) on the frequency, intensity and current flow output in association with electroacupuncture (EA) sensations. MethodsTwenty one volunteers received EA. According to the tissue specificities of acupoints, 5 acupoint pairs were selected, named Zùsānl▪ (▪ ST 36) vs Yánglíngquán (▪ GB 34, different meridians), Nèiguān (▪ PC 6) vs Dàlíng (▪ PC 7, different tissues), Zùsānl▪ (▪ ST 36) vs Shu▪dào (▪ ST 28, different nerve segments), Guānyuán (▪ CV 4) vs Zhōngwán (▪ CV 12, different nerve segments), and Zùsānl▪ (▪ ST 36) vs Guānyuán(▪ CV 4, different meridians, tissues and nerve segments). The electric frequency was 15 Hz. The electric current was under the subject's tolerance without sharp pain induced. EA lasted 90 s with 3 discontinuities. The sensations, such as soreness, numbness, fullness/distention, heaviness, tingling, pressure, dull pain, hotness and coldness were recorded as well as the current flow output in association with the needling sensations. The differences in the frequency, intensity and current flow output relevant with the needling sensations were compared among the different acupoint pairs. ResultsThere were no significant differences in the frequency of the needling sensations among the different acupoint pairs (all P<0.05). Of 9 different sensations of EA, fullness/distention, numbness and soreness presented the most commonly and remarkably; heaviness, pressure and tingling were on the second top; dull pain, hotness and coldness occurred at the lower frequency. There were the differences in the intensity of some needling sensations among the acupoint pairs, in which, the intensity of soreness, fullness/distention and heaviness was stronger at Zùsānl▪ (▪ ST 36) vs Shu▪dào (▪ ST 28) (all P<0.05); the intensity of fullness/distention, and numbness was stronger at Zùsānl▪ (▪ ST 36) vs Guānyuán (▪ CV 4) P<0.01); the intensity of fullness/distention was stronger at Guānyuán (▪ CV 4) vs Zhōngw▪n (▪ CV 12) (P<0.05). The current flow output of EA was similar among the acupoint pairs (all P<0.05). ConclusionIn the situation that there is no obvious difference in the current flow output associated with EA sensations, the frequency of EA sensations does not relevant apparently with the different tissues. The difference in the intensity of the needling sensations among the different acupoints is probably relevant with the nerve segments at the acupoint locations. The frequency and the intensity of the different needling sensations at the same acupoint are relatively stable at the different times of EA.

Contextual Modulation of Contour Detection is Altered in Schizophrenia

Contour detection is an important step in early visual processing that facilitates figure-ground segmentation and object recognition. Patients with schizophrenia show abnormalities in early visual processing, and contour detection deficits have been observed in those with this disorder. It has recently been shown that during contour detection, nearby elements that are not part of a contour can influence detection thresholds, an effect referred to here as contextual modulation. The valence of this modulation depends on the relative orientation between contour elements and flankers, and agrees with known orientation selective surround suppression (OSSS) effects. It has also been shown that the OSSS effect is diminished in subjects with schizophrenia. However, is it currently unknown how deficits in OSSS in schizophrenia may influence contextual modulation by flanking elements during contour detection. Therefore, we measured contour detection thresholds in healthy adults and those with schizophrenia in a psychophysics experiment. Stimuli consisted of an array of Gabor elements with a vertically oriented group of elements forming a target contour to the left or right of fixation. Thresholds were obtained by determining a subject's tolerance to jitter in the orientation of target elements. Stimulus context differed between conditions, and was defined by the relative orientation between contour elements and flankers (5 Gabors flanking left & right of both possible target locations). Within subject groups, thresholds for randomly or orthogonally oriented flankers are significantly higher than for parallel flankers. In general, subjects with schizophrenia performed better on the task than healthy controls, with a significant increase in performance in the orthogonal condition, relative to randomly oriented flankers, that was not observed in controls. Increased performance in the orthogonal condition constitutes a context-specific visual processing abnormality during contour detection, and suggests broader tuning of orientation-dependent lateral masking effects in schizophrenia.

Central and Peripheral Fatigue during Passive and Exercise-Induced Hyperthermia

Hyperthermia was induced during prolonged exercise (ExH) and passive heating (PaH) to isolate the influence of exercise on neuromuscular function during a maximal voluntary isometric contraction (MVC) of the quadriceps under heat stress. The influence of cardiovascular strain in limiting endurance performance in the heat was also examined. On separate days, eight males cycled to exhaustion at 60% maximal oxygen uptake or were immersed in a water bath (∼41°C) until rectal temperature (Tre) increased to 39.5°C. The ExH and PaH interventions were performed in ambient conditions of 38°C and 60% relative humidity with Tre reaching 39.8°C during exercise. Before (control) and after each intervention, voluntary activation and force production capacity were evaluated by superimposing an electrically stimulated tetanus during a 45-s MVC. Force production decreased immediately after PaH and ExH compared with control, with the magnitude of decline being more pronounced after ExH (P < 0.01). Mean voluntary activation was also significantly depressed after both interventions (P < 0.01 vs control). However, the extent of decline in voluntary activation was maintained at ∼90% during both PaH and ExH MVC. This decline accounted for 41.5% (PaH) and 33.1% (ExH) of the decrease in force production. In addition, exhaustion coincided with a marked increase in HR (∼96% of maximum) and a decline in stroke volume (25%) and mean arterial pressure (10%) (P < 0.05). The loss of force production capacity during hyperthermia originated from central and peripheral fatigue factors, with the combination of heat stress and previous contractile activity exacerbating the rate of decline. Thus, the observed significant rise in thermal strain in ExH and PaH impaired neuromuscular function and was associated with an exercise performance limiting increase in cardiovascular strain.

Transcutaneous neuromuscular electrical stimulation: influence of electrode positioning and stimulus amplitude settings on muscle response

The aim of the study was to investigate the influence of two different transcutaneous neuromuscular electrical stimulation procedures on evoked muscle torque and local tissue oxygenation. In the first one (MP mode), the cathode was facing the muscle main motor point and stimulus amplitude was set to the level eliciting the maximal myoelectrical activation according to the amplitude of the evoked electromyogram (EMG); in the second one (RC mode), the electrodes were positioned following common reference charts for electrode placement while stimulus amplitude was set according to subject tolerance. Tibialis Anterior (TA) and Vastus Lateralis (VL) muscles of 10 subjects (28.4±8.2years) were tested in specific dynamometers to measure the evoked isometric torque. The EMG and near-infrared spectroscopy probes were placed on muscle belly to detect the electrical activity and local metabolic modifications of the stimulated muscle, respectively. The stimulation protocol consisted of a gradually increasing frequency ramp from 2 to 50Hz in 7.5s. Compared to RC mode, in MP mode the contractile parameters (peak twitch, tetanic torque, area under the torque build-up) and the metabolic solicitation (oxygen consumption and hyperemia due to metabolites accumulation) resulted significantly higher for both TA and VL muscles. MP mode resulted also to be more comfortable for the subjects. Based on the assumption that proper mechanical and metabolic stimuli are necessary to induce muscle strengthening, our results witness the importance of an optimized, i.e., comfortable and effective, stimulation to promote the aforementioned muscle adaptive modifications.