Ictal central apnoea is a feature of focal temporal seizures. It is implicated as a risk factor for sudden unexpected death in epilepsy (SUDEP). Here we study seizure-related apnoeas in two different models of experimental seizures, one chronic and one acute, in adult genetically-unmodified rats, to determine mechanisms of seizure-related apnoeas. Under general anaesthesia rats receive sensors for nasal temperature, hippocampal and/or neocortical potentials, and ECG or EMG for subsequent tethered video-telemetry. Tetanus neurotoxin (TeNT), injected into hippocampus during surgery, induces a chronic epileptic focus. Other implanted rats receive intraperitoneal pentylenetetrazol (PTZ) to evoke acute seizures. In chronically epileptic rats, convulsive seizures cause apnoeas (9.9 ± 5.3 s; 331 of 730 convulsive seizures in 15 rats), associated with bradyarrhythmias. Absence of EEG and ECG biomarkers exclude obstructive apnoeas. All eight TeNT-rats with diaphragm EMG have apnoeas with no evidence of obstruction, and have apnoea EMGs significantly closer to expiratory relaxation than inspiratory contraction during pre-apnoeic respiration, which we term "atonic diaphragm". Consistent with atonic diaphragm is that the pre-apnoeic nasal airflow is expiration, as it is in human ictal central apnoea. Two cases of rat sudden death occur. One, with telemetry to the end, reveals a lethal apnoea, the other only has video during the final days, which reveals cessation of breathing shortly after the last clonic epileptic movement. Telemetry following acute systemic PTZ reveals repeated seizures and seizure-related apnoeas, culminating in lethal apnoeas; ictal apnoeas are central - in 8 of 35 cases diaphragms initially contract tonically for 8.5 ± 15.0 s before relaxing, in the 27 remaining cases diaphragms are atonic throughout apnoeas. All terminal apnoeas are atonic. Differences in types of apnoea due to systemic PTZ in rats (mainly atonic) and mice (tonic) are likely species-specific. Certain genetic mouse models have apnoeas caused by tonic contraction, potentially due to expression of epileptogenic mutations throughout the brain, including in respiratory centres, in contrast with acquired focal epilepsies. We conclude that ictal apnoeas in the rat TeNT model result from atonic diaphragms. Relaxed diaphragms could be particularly helpful for therapeutic stimulation of the diaphragm to help restore respiration.

• Klíčová slova
• EMG, Pentylenetetrazol, SUDEP, Temporal lobe epilepsy, Tetanus toxin, hippocampus,
• MeSH
• apnoe patofyziologie   MeSH
• bránice * patofyziologie   MeSH
• chronická nemoc MeSH
• elektroencefalografie MeSH
• krysa rodu Rattus MeSH
• modely nemocí na zvířatech * MeSH
• pentylentetrazol toxicita   MeSH
• potkani Sprague-Dawley MeSH
• relaxace svalu fyziologie   MeSH
• tetanový toxin toxicita   MeSH
• záchvaty * patofyziologie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• pentylentetrazol MeSH
• tetanový toxin MeSH

BACKGROUND: The Dynamic Neuromuscular Stabilization (DNS) diaphragm test and intra-abdominal pressure regulation test (IAPRT) are qualitative clinical tests that assess postural stability provided by the diaphragm. OBJECTIVE: Evaluate the inter-rater reliability of the diaphragm test and IAPRT between an experienced and novice DNS clinician among individuals with non-specific low back pain (LBP) and neck pain. METHODS: Forty-five participants with non-specific LBP and/or neck pain were assessed by an experienced and novice DNS physiotherapist in the diaphragm test and IAPRT, and scored on a visual analog scale (VAS) according to five different criteria. RESULTS: Moderate reliability was noted when assessing LBP and neck pain patients in the diaphragm test and IAPRT (p < 0.001). Moderate reliability also existed when assessing only LBP (p < 0.001) or neck pain (p = 0.002, p = 0.009) independently. Patients with lower pain (NPRS score of 5 or < ) demonstrated lower intra-class correlation coefficients, yet still moderate reliability in the diaphragm test (p = 0.004) and IAPRT (p = 0.001). Patients with higher pain (NPRS score of 6 or > ) demonstrated greater intra-class correlation coefficients, with the diaphragm test resulting in good reliability (p < 0.001). CONCLUSIONS: The diaphragm test and IAPRT demonstrate moderate reliability between an experienced and novice DNS clinician when evaluating LBP and neck pain patients, with a greater degree of reliability noted in patients suffering from higher reported pain.

• Klíčová slova
• Back pain, Diaphragm, Inter-rater, Neck pain, Postural stabilization, Postural-respiratory function, Reliability,
• MeSH
• bolest krku * patofyziologie   diagnóza   MeSH
• bránice * patofyziologie   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• lumbalgie * patofyziologie   diagnóza   MeSH
• měření bolesti metody   MeSH
• odchylka pozorovatele MeSH
• posturální rovnováha fyziologie   MeSH
• reprodukovatelnost výsledků MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

BACKGROUND: Diaphragm atrophy and dysfunction is a major problem among critically ill patients on mechanical ventilation. Ventilator-induced diaphragmatic dysfunction is thought to play a major role, resulting in a failure of weaning. Stimulation of the phrenic nerves and resulting diaphragm contraction could potentially prevent or treat this atrophy. The subject of this study is to determine the effectiveness of diaphragm stimulation in preventing atrophy by measuring changes in its thickness. METHODS: A total of 12 patients in the intervention group and 10 patients in the control group were enrolled. Diaphragm thickness was measured by ultrasound in both groups at the beginning of study enrollment (hour 0), after 24 hours, and at study completion (hour 48). The obtained data were then statistically analyzed and both groups were compared. RESULTS: The results showed that the baseline diaphragm thickness in the interventional group was (1.98 ± 0.52) mm and after 48 hours of phrenic nerve stimulation increased to (2.20 ± 0.45) mm (p=0.001). The baseline diaphragm thickness of (2.00 ± 0.33) mm decreased in the control group after 48 hours of mechanical ventilation to (1.72 ± 0.20) mm (p<0.001). CONCLUSIONS: Our study demonstrates that induced contraction of the diaphragm by pacing the phrenic nerve not only reduces the rate of its atrophy during mechanical ventilation but also leads to an increase in its thickness - the main determinant of the muscle strength required for spontaneous ventilation and successful ventilator weaning. TRIAL REGISTRATION: The study was registered with ClinicalTrials.gov (18/06/2018, NCT03559933, https://clinicaltrials.gov/ct2/show/NCT03559933 ).

• Klíčová slova
• Diaphragm atrophy, Phrenic nerve, Ultrasound, Weaning from mechanical ventilation,
• MeSH
• bránice diagnostické zobrazování   patofyziologie   MeSH
• elektrostimulační terapie přístrojové vybavení   metody   MeSH
• kritický stav MeSH
• lidé středního věku MeSH
• lidé MeSH
• nervus phrenicus fyziologie   MeSH
• prospektivní studie MeSH
• respirační insuficience terapie   MeSH
• senioři MeSH
• svalová atrofie etiologie   patofyziologie   MeSH
• ultrasonografie MeSH
• umělé dýchání škodlivé účinky   metody   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH

Chronic airflow limitation, caused by chronic obstructive pulmonary disease (COPD) or by asthma, is believed to change the shape and the position of the diaphragm due to an increase in lung volume. We have made a comparison of magnetic resonance imaging (MRI) of diaphragm in supine position with pulmonary functions, respiratory muscle function and exercise tolerance. We have studied the differences between patients with COPD, patients with asthma, and healthy subjects. Most interestingly we found the lung hyperinflation leads to the changes in diaphragmatic excursions during the breathing cycle, seen in the differences between the maximal expiratory diaphragm position (DPex) in patients with COPD and control group (p=0.0016). The magnitude of the diaphragmatic dysfunction was significantly related to the airflow limitation expressed by the ratio of forced expiratory volume in 1 s to slow vital capacity (FEV(1)/SVC), (%, p=0.0007); to the lung hyperinflation expressed as the ratio of the residual volume to total lung capacity (RV/TLC), (%, p=0.0018) and the extent of tidal volume constrain expressed as maximal tidal volume (V(Tmax)), ([l], p=0.0002); and the ratio of tidal volume to slow vital capacity (V(T)/SVC), (p=0.0038) during submaximal exercise. These results suggest that diaphragmatic movement fails to contribute sufficiently to the change in lung volume in emphysema. Tests of respiratory muscle function were related to the position of the diaphragm in deep expiration, e.g. neuromuscular coupling (P(0.1)/V(T)) (p=0.0232). The results have shown that the lung volumes determine the position of the diaphragm and function of the respiratory muscles. Chronic airflow limitation seems to change the position of the diaphragm, which thereafter influences inspiratory muscle function and exercise tolerance. There is an apparent relationship between the position of the diaphragm and the pulmonary functions and exercise tolerance.

• MeSH
• bránice patofyziologie   MeSH
• bronchiální astma patofyziologie   MeSH
• chronická obstrukční plicní nemoc patofyziologie   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• respirační funkční testy MeSH
• senioři MeSH
• studie případů a kontrol MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

We present a postural analysis of diaphragm function using magnetic resonance imaging (MRI). The main aim of the study was to identify changes in diaphragm motion and shape when postural demands on the body were increased (loading applied to a distal part of the extended lower extremities against the flexion of the hips was used). Sixteen healthy subjects were compared with 17 subjects suffering from chronic low back pain and in whom structural spine disorders had been identified. Two sets of features were calculated from MRI recordings: dynamic parameters reflecting diaphragm action, and static parameters reflecting diaphragm anatomic characteristics. A statistical analysis showed that the diaphragm respiratory and postural changes were significantly slower, bigger in size and better balanced in the control group. When a load was applied to the lower limbs, the pathological subjects were mostly not able to maintain the respiratory diaphragm function, which was lowered significantly. Subjects from the control group showed more stable parameters of both respiratory and postural function. Our findings consistently affirmed worse muscle cooperation in the low back pain population subgroup. A clear relation with spinal findings and with low back pain remains undecided, but various findings in the literature were confirmed. The most important finding is the need to further address various mechanisms used by patients to compensate deep muscle insufficiency.

• MeSH
• bránice fyziologie   patofyziologie   MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• magnetická rezonanční tomografie * MeSH
• mechanika dýchání MeSH
• mladý dospělý MeSH
• páteř MeSH
• pohyb těles MeSH
• postura těla * MeSH
• posturální rovnováha MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

STUDY DESIGN: A case-control study. OBJECTIVES: To examine the function of the diaphragm during postural limb activities in patients with chronic low back pain and healthy controls. BACKGROUND: Abnormal stabilizing function of the diaphragm may be an etiological factor in spinal disorders. However, a study designed specifically to test the dynamics of the diaphragm in chronic spinal disorders is lacking. METHODS: Eighteen patients with chronic low back pain due to chronic overloading, as ascertained via clinical assessment and magnetic resonance imaging, and 29 healthy subjects were examined. Both groups presented with normal pulmonary function test results. A dynamic magnetic resonance imaging system and specialized spirometric readings were used with subjects in the supine position. Measurements during tidal breathing (TB) and isometric flexion of the upper and lower extremities against external resistance with TB were performed. Standard pulmonary function tests, including respiratory muscle drive (PI(max) and PE(max)), were also assessed. RESULTS: Using multivariate analysis of covariance, smaller diaphragm excursions and higher diaphragm position were found in the patient group (P<.05) during the upper extremity TB and lower extremity TB conditions. Maximum changes were found in costal and middle points of the diaphragm. A 1-way analysis of covariance showed a steeper slope in the middle-posterior diaphragm in the patient group both in the upper extremity TB and lower extremity TB conditions (P<.05). CONCLUSION: Patients with chronic low back pain appear to have both abnormal position and a steeper slope of the diaphragm, which may contribute to the etiology of the disorder.

• MeSH
• bránice patofyziologie   MeSH
• břišní svaly patofyziologie   MeSH
• chronická nemoc MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• lumbalgie diagnóza   etiologie   patofyziologie   MeSH
• magnetická rezonanční tomografie MeSH
• mladý dospělý MeSH
• posturální rovnováha fyziologie   MeSH
• respirační funkční testy MeSH
• studie případů a kontrol MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Progressive motoneuronopathy (PMN) is an autosomal recessive mouse disease, which is characterized by the development of hind limbs paralysis rapidly progressing to the anterior parts of the body, muscular atrophy, respiratory depression, and death at 6-7 postnatal weeks. Here, we recorded the resting membrane potential (RMP), spontaneous miniature endplate potentials (MEPPs), and quantum content of endplate potentials (EPP) at the diaphragm muscle fibers in controls and PMN mice aged 18 to 43 days. In control animals, there was a progressive increase in RMP, MEPP frequency and EPP quantum content, as well as a decrease in mean MEPP amplitude. In PMN mice, the developmental increase in frequency and decrease in the amplitude of MEPPs was practically stopped at the postnatal day 18, whereas RMP increased but only until the age of 31 days and then progressively decreased. The distribution histogram of RMP in PMN mice older than 35 days revealed the existence of two subpopulations of muscle fibers: one showing a denervation-like decrease in RMP and the second, which was matching controls. In addition, EPP quantum content was significantly attenuated in older PMN animals. These results indicate that neurotransmission is severely affected in advanced, but not in early stage of disease, which is apparently due to a partial denervation of the muscles.

• MeSH
• bránice inervace   patologie   patofyziologie   MeSH
• myši - mutanty neurologické MeSH
• myši MeSH
• nervový přenos * MeSH
• onemocnění motorického neuronu patologie   patofyziologie   MeSH
• progrese nemoci MeSH
• stárnutí * MeSH
• stupeň závažnosti nemoci MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

We studied the temporal relationships and the patterns of electromyographic activities of the posterior cricoarytenoid and thyreoarytenoid muscles (laryngeal abductor and adductor), the diaphragm and abdominal muscles in anesthetized cats during mechanically induced tracheobronchial and laryngopharyngeal coughs, expiration and aspiration reflexes. The posterior cricoarytenoid muscle activity reached the maxima just before the peak of diaphragmatic activity in both types of cough and aspiration reflexes and slightly before the top of abdominal muscle activity in coughs and the expiration reflex. Thus, this muscle contributes to the inspiratory phase of coughs and aspiration reflex and also to the expulsive phase of coughs and the expiration reflex. The thyreoarytenoid muscle presented strong discharges in the compressive phase of coughs and expiration reflex (during the rising part of the abdominal muscle activity) and in the subsequent laryngoconstriction (following the diaphragmal and/or abdominal muscle activity) in all four reflexes. This muscle was also slightly activated at the beginning of the aspiration reflex. The existence of four phases of the cough reflex is also discussed.

• MeSH
• bránice patofyziologie   MeSH
• břišní svaly patofyziologie   MeSH
• elektrofyziologie MeSH
• kašel patofyziologie   MeSH
• kočky MeSH
• krevní tlak fyziologie   MeSH
• laryngální svaly patofyziologie   MeSH
• nadechnutí fyziologie   MeSH
• nervus laryngeus recurrens patofyziologie   MeSH
• reflex fyziologie   MeSH
• tlak MeSH
• trachea patofyziologie   MeSH
• vydechnutí fyziologie   MeSH
• zvířata MeSH
• Check Tag
• kočky MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

• MeSH
• bránice patofyziologie   MeSH
• elektrická stimulace MeSH
• hepatektomie MeSH
• lidé MeSH
• nádory jater komplikace   chirurgie   MeSH
• nádory rekta komplikace   chirurgie   MeSH
• nádory slinivky břišní komplikace   chirurgie   MeSH
• nervová blokáda metody   MeSH
• nervus phrenicus diagnostické zobrazování   fyziologie   MeSH
• nezvladatelná bolest komplikace   terapie   MeSH
• pooperační komplikace terapie   MeSH
• senioři MeSH
• škytavka etiologie   terapie   MeSH
• ultrasonografie MeSH
• umělé dýchání škodlivé účinky   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• Publikační typ
• časopisecké články MeSH
• kazuistiky MeSH

To determine the role of postinspiratory inspiratory activity of the diaphragm in the biphasic ventilatory response to hypoxia in unanesthetized rats, we examined diaphragmatic activity at its peak (DI), at the end of expiration (DE), and ventilation in adult unanesthetized rats during poikilocapnic hypoxia (10 % O2) sustained for 20 min. Hypoxia induced an initial increase in ventilation followed by a consistent decline. Tidal volume (VT), frequency of breathing (fR), DI and DE at first increased, then VT and DE decreased, while fR and DI remained enhanced. Phasic activation of the diaphragm (DI-DE) increased significantly at 10, 15 and 20 min of hypoxia. These results indicate that 1) the ventilatory response of unanesthetized rats to sustained hypoxia has a typical biphasic character and 2) the increased end-expiratory activity of the diaphragm limits its phasic inspiratory activation, but this increase cannot explain the secondary decline in tidal volume and ventilation.

• MeSH
• bránice patofyziologie   MeSH
• dechový objem MeSH
• dýchání MeSH
• hypoxie patofyziologie   MeSH
• kinetika MeSH
• krysa rodu Rattus MeSH
• kyslík aplikace a dávkování   MeSH
• plicní ventilace * MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• kyslík MeSH