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BMJ Sexual & Reproductive Health Jul 2022
Topics: Computer-Assisted Instruction; Contraception; Female; Humans; Intrauterine Devices; Students, Medical
PubMed: 34949689
DOI: 10.1136/bmjsrh-2021-201401 -
Physiological Reports Jan 2023After a bout of isolated inspiratory work, such as inspiratory pressure threshold loading (IPTL), the human diaphragm can exhibit a reversible loss in contractile...
After a bout of isolated inspiratory work, such as inspiratory pressure threshold loading (IPTL), the human diaphragm can exhibit a reversible loss in contractile function, as evidenced by a decrease in transdiaphragmatic twitch pressure (P ). Whether or not diaphragm fatigability after IPTL is affected by neural mechanisms, measured through voluntary activation of the diaphragm (D-VA) in addition to contractile mechanisms, is unknown. It is also unknown if changes in D-VA are similar between sexes given observed differences in diaphragm fatigability between males and females. We sought to determine whether D-VA decreases after IPTL and whether this was different between sexes. Healthy females (n = 11) and males (n = 10) completed an IPTL task with an inspired duty cycle of 0.7 and targeting an intensity of 60% maximal transdiaphragmatic pressure until task failure. P and D-VA were measured using cervical magnetic stimulation of the phrenic nerves in combination with maximal inspiratory pressure maneuvers. At task failure, P decreased to a lesser degree in females vs. males (87 ± 15 vs. 73 ± 12% baseline, respectively, p = 0.016). D-VA decreased after IPTL but was not different between females and males (91 ± 8 vs. 88 ± 10% baseline, respectively, p = 0.432). When all participants were pooled together, the decrease in P correlated with both the total cumulative diaphragm pressure generation (R = 0.43; p = 0.021) and the time to task failure (TTF, R = 0.40; p = 0.30) whereas the decrease in D-VA correlated only with TTF (R = 0.24; p = 0.041). Our results suggest that neural mechanisms can contribute to diaphragm fatigability, and this contribution is similar between females and males following IPTL.
Topics: Male; Female; Humans; Diaphragm; Thorax; Muscle Contraction; Phrenic Nerve
PubMed: 36695772
DOI: 10.14814/phy2.15575 -
Experimental Neurology May 2021Acute intermittent hypoxia (AIH) is a strategy to improve motor output in humans with neuromotor impairment. A single AIH session increases the amplitude of motor evoked...
Acute intermittent hypoxia (AIH) is a strategy to improve motor output in humans with neuromotor impairment. A single AIH session increases the amplitude of motor evoked potentials (MEP) in a finger muscle (first dorsal interosseous), demonstrating enhanced corticospinal neurotransmission. Since AIH elicits phrenic/diaphragm long-term facilitation (LTF) in rodent models, we tested the hypothesis that AIH augments diaphragm MEPs in humans. Eleven healthy adults (7 males, age = 29 ± 6 years) were tested. Transcranial and cervical magnetic stimulation were used to induce diaphragm MEPs and compound muscle action potentials (CMAP) recorded by surface EMG, respectively. Stimulus-response curves were generated prior to and 30-60 min after AIH. Diaphragm LTF was assessed by measurement of integrated EMG burst amplitude and frequency during eupnoeic breathing before and after AIH. Following baseline measurements, AIH was delivered from an oxygen generator connected to a facemask under poikilocapnic conditions (15 one minute episodes of 9% inspired oxygen with one minute room air intervals). There were no detectable changes in MEP (-1.5 ± 12.1%, p = 0.96) or CMAP (+0.1 ± 7.8%, p = 0.97) amplitudes across the stimulus-response curve. At stimulation intensities approximating 50% of the difference between minimum and maximum baseline amplitudes, MEP and CMAP amplitudes were also unchanged (p > 0.05). Further, no AIH effect was observed on diaphragm EMG activity during eupnoea post-AIH (p > 0.05). We conclude that unlike hand muscles, poikilocapnic AIH does not enhance diaphragm MEPs or produce diaphragm LTF in healthy humans.
Topics: Acute Disease; Adult; Cervical Cord; Diaphragm; Electromyography; Evoked Potentials, Motor; Female; Humans; Hypoxia; Long-Term Potentiation; Male; Phrenic Nerve; Respiratory Mechanics; Transcranial Magnetic Stimulation; Young Adult
PubMed: 33607080
DOI: 10.1016/j.expneurol.2021.113651 -
Taiwanese Journal of Obstetrics &... Mar 2023We aimed to investigate whether there is a relationship between diaphragm thickness and disease severity in Covid-19 pregnant subgroups.
OBJECTIVE
We aimed to investigate whether there is a relationship between diaphragm thickness and disease severity in Covid-19 pregnant subgroups.
MATERIAL AND METHODS
In this prospective study 100 pregnant patients were enrolled. Thickness of the diaphragm muscle at end-expiration was measured using B-Mode US. Hemoglobin,WBC, NLR, procalcitonin and LDH levels were measured.
RESULTS
There was a statistically significant difference between the groups in terms of diaphragm thickness, and the diaphragm thickness was thinner in the severe disease group (p < 0.001). There was no statistically significant difference between the groups with mild to moderate disease severity (p = 0.708).
CONCLUSION
Covid-19 patients who developed serious infection has thinner diaphragms than those who did not. Low diaphragm muscle thickness at the outset of Covid-19 disease, may predispose to poor clinical outcomes. Diaphragmatic ultrasound may be a promising tool to evaluate the risk of Covid-19 disease severity.
Topics: Humans; Pregnancy; Female; Diaphragm; Prospective Studies; COVID-19; Ultrasonography
PubMed: 36965895
DOI: 10.1016/j.tjog.2022.10.008 -
Journal of Healthcare Engineering 2022When the human body is anesthetized, the human nerve tissue will be greatly affected, which also affects the breathing of the human body. The respiration during...
When the human body is anesthetized, the human nerve tissue will be greatly affected, which also affects the breathing of the human body. The respiration during anesthesia is a lack of initiative, and the energy efficiency of the diaphragm in the lungs is very important to the safety of anesthesia. In this paper, the application of the ultrasound evaluation of the diaphragm in clinical anesthesia was studied. In this paper, 24 patients who underwent lung examination under medical anesthesia at our hospital were evaluated by the ultrasound vertical mixed echo method. Through patient voluntary selection and consent, 16 patients were examined with B-mode ultrasound and the other 8 patients with M-mode ultrasound to compare the effects of different ultrasounds on diaphragm image quality. In addition, this paper also analyzes the differences between different ultrasounds and the strengths and weaknesses of diaphragmatic ultrasound evaluation in clinical anesthesia. The suggestions of using different ultrasounds in ultrasonic evaluation are given. The study showed that 16 cases of B-mode ultrasound evaluation of the diaphragm obtained ultrasound images which showed a large field of vision, acoustic frequency between 7 and 18 MHz, and thickness difference between 0.35 and 0.52 cm. In 8 patients with the diaphragm evaluated by M-mode ultrasound, the local features of M-mode ultrasound images were clearer than those of B-mode ultrasound images, but the visual field area was smaller, the acoustic frequency was between 10 and 15 MHz, and the thickness difference was between 0.12 and 0.18 cm. Based on the above data, this paper suggests that, in the ultrasonic evaluation of the diaphragm, B-mode ultrasound should be used to check the patients first, and then M-mode ultrasound should be used to check the parts with poor quality so that the accurate diaphragm quality of patients can be obtained in the vast majority of patients.
Topics: Anesthesia; Diaphragm; Humans; Respiration; Thorax; Ultrasonography
PubMed: 35281531
DOI: 10.1155/2022/2163225 -
Histology and Histopathology Jul 2021The mdx mouse model of Duchenne Muscular Dystrophy (DMD) presents sarcolemma instability and develops a mild multi-stage dystrophinopathy characterized by intense...
The mdx mouse model of Duchenne Muscular Dystrophy (DMD) presents sarcolemma instability and develops a mild multi-stage dystrophinopathy characterized by intense myonecrosis with inflammatory infiltrate at 4-weeks; muscular regeneration at 12-weeks and persistent fibrosis onwards. Mdx diaphragm muscle has a more severe phenotype with structural and functional deterioration that closely resembles the diaphragm impairment responsible for DMD human patients' morbidity. Herein, we compared calcium deposits, activity of calcium-related proteases, and expression of muscle-specific proteins in mdx diaphragm at 4-weeks and 12-weeks. We found increased calcium deposits mainly at 12-weeks, concomitant with high activity of calpains and matrix metalloprotease-9, but decreased expression of Myh4 (Myhc IIb) and Atp2a1 (SERCA1), and high expression of the myogenic regulatory factors Myod1 and Myog. Our results suggest that increased calcium deposits and persistent activity of calcium dependent proteases throughout the disease are involved in the degeneration and regeneration processes in the mdx diaphragm.
Topics: Animals; Calcium; Diaphragm; Male; Mice; Mice, Inbred mdx; Muscle Proteins; Muscular Dystrophy, Duchenne
PubMed: 33825181
DOI: 10.14670/HH-18-334 -
Respiration; International Review of... 2020Reference values derived from existing diaphragm ultrasound protocols are inconsistent, and the association between sonographic measures of diaphragm function and...
BACKGROUND
Reference values derived from existing diaphragm ultrasound protocols are inconsistent, and the association between sonographic measures of diaphragm function and volitional tests of respiratory muscle strength is still ambiguous.
OBJECTIVE
To propose a standardized and comprehensive protocol for diaphragm ultrasound in order to determine lower limits of normal (LLN) for both diaphragm excursion and thickness in healthy subjects and to explore the association between volitional tests of respiratory muscle strength and diaphragm ultrasound parameters.
METHODS
Seventy healthy adult subjects (25 men, 45 women; age 34 ± 13 years) underwent spirometric lung function testing, determination of maximal inspiratory and expiratory pressure along with ultrasound evaluation of diaphragm excursion and thickness during tidal breathing, deep breathing, and maximum voluntary sniff. Excursion data were collected for amplitude and velocity of diaphragm displacement. Diaphragm thickness was measured in the zone of apposition at total lung capacity (TLC) and functional residual capacity (FRC). All participants underwent invasive measurement of transdiaphragmatic pressure (Pdi) during different voluntary breathing maneuvers.
RESULTS
Ultrasound data were successfully obtained in all participants (procedure duration 12 ± 3 min). LLNs (defined as the 5th percentile) for diaphragm excursion were as follows: (a) during tidal breathing: 1.2 cm (males; M) and 1.2 cm (females; F) for amplitude, and 0.8 cm/s (M) and 0.8 cm/s (F) for velocity, (b) during maximum voluntary sniff: 2.0 cm (M) and 1.5 cm (F) for amplitude, and 6.7 (M) cm/s and 5.2 cm/s (F) for velocity, and (c) at TLC: 7.9 cm (M) and 6.4 cm (F) for amplitude. LLN for diaphragm thickness was 0.17 cm (M) and 0.15 cm (F) at FRC, and 0.46 cm (M) and 0.35 cm (F) at TLC. Values for males were consistently higher than for females, independent of age. LLN for diaphragmatic thickening ratio was 2.2 with no difference between genders. LLN for invasively measured Pdi during different breathing maneuvers are presented. Voluntary Pdi showed only weak correlation with both diaphragm excursion velocity and amplitude during forced inspiration.
CONCLUSIONS
Diaphragm ultrasound is an easy-to-perform and reproducible diagnostic tool for noninvasive assessment of diaphragm excursion and thickness. It supplements but does not replace respiratory muscle strength testing.
Topics: Adult; Diaphragm; Female; Functional Residual Capacity; Healthy Volunteers; Humans; Male; Maximal Respiratory Pressures; Middle Aged; Muscle Strength; Reference Values; Respiratory Muscles; Spirometry; Total Lung Capacity; Ultrasonography; Young Adult
PubMed: 32396905
DOI: 10.1159/000506016 -
American Journal of Obstetrics and... Apr 2023Recent evidence demonstrates the effectiveness of the levonorgestrel 52-mg intrauterine device for emergency contraception vs the copper T380A intrauterine device. Of... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Recent evidence demonstrates the effectiveness of the levonorgestrel 52-mg intrauterine device for emergency contraception vs the copper T380A intrauterine device. Of note, 1-year pregnancy and continuation rates after intrauterine device placement for emergency contraception remain understudied.
OBJECTIVE
This study compared 1-year pregnancy and intrauterine device continuation rates and reasons for discontinuation among emergency contraception users randomized to the levonorgestrel 52-mg intrauterine device or the copper intrauterine device.
STUDY DESIGN
This participant-masked, randomized noninferiority trial recruited emergency contraception individuals desiring an intrauterine device from 6 Utah family planning clinics between August 2016 and December 2019. Participants were randomized 1:1 to the levonorgestrel 52-mg intrauterine device group or the copper T380A intrauterine device group. Treatment allocation was revealed to participants at the 1-month follow-up. Trained personnel followed up the participants by phone, text, or e-mail at 5 time points in 1 year and reviewed electronic health records for pregnancy and intrauterine device continuation outcomes for both confirmation and nonresponders. We assessed the reasons for the discontinuation and used Cox proportional-hazard models, Kaplan-Meier estimates, and log-rank tests to assess differences in the continuation and pregnancy rates between the groups.
RESULTS
The levonorgestrel and copper intrauterine device groups included 327 and 328 participants, respectively, receiving the respective interventions. By intention-to-treat analysis at 1 year, the pregnancy rates were similar between intrauterine device types (2.8% [9/327] in levonorgestrel 52-mg intrauterine device vs 3.0% [10/328] in copper intrauterine device; risk ratio, 0.9; 95% confidence interval, 0.4-2.2; P=.82). Most pregnancies occurred in participants after intrauterine device removal, with only 1 device failure in each group. Of note, 1-year continuation rates did not differ between groups with 204 of 327 levonorgestrel 52-mg intrauterine device users (62.4%) and 183 of 328 copper T380A intrauterine device users (55.8%) continuing intrauterine device use at 1 year (risk ratio, 1.1; 95% confidence interval, 1.0-1.2; P=.09). There were differences concerning the reasons for discontinuation between intrauterine device types, with more bleeding and cramping cited among copper intrauterine device users.
CONCLUSION
The pregnancy rates were low and similar between intrauterine device types. Of note, 6 of 10 intrauterine device emergency contraception users continued use at 1 year. Moreover, 1-year continuation rates were similar between intrauterine device types.
Topics: Pregnancy; Female; Humans; Levonorgestrel; Intrauterine Devices, Copper; Contraception, Postcoital; Intrauterine Devices; Utah; Intrauterine Devices, Medicated; Contraceptive Agents, Female
PubMed: 36427600
DOI: 10.1016/j.ajog.2022.11.1296 -
Journal of Food Biochemistry Dec 2022Walnut diaphragm is defined as a dry wood septum located between the walnut shell and kernel. In this work, seven phenolic compounds from walnut diaphragm were purified...
Walnut diaphragm is defined as a dry wood septum located between the walnut shell and kernel. In this work, seven phenolic compounds from walnut diaphragm were purified and characterized, and their antioxidant activities and mechanisms of hypoglycemia were investigated. Compounds 1-7 were tested for DPPH, ABTS scavenging ability, and FRAP assay to evaluate the antioxidant activity. α-Amylase inhibition assay was introduced to assess the hypoglycemic activity, and the mechanism was investigated by kinetic analysis, CD spectrum, and molecular docking. Compound 6 showed the strongest antioxidant ability, while compound 1 exhibited the strongest inhibition of α-amylase by changing the secondary structure of α-amylase in a mixed competitive inhibition mode. Molecular docking test predicted that the tetrahydropyran part in compound 1 may contribute to its hypoglycemic effect. This study furnishes a new theoretical reference for the utilization and development of walnut diaphragm into a health food with antioxidant and hypoglycemic properties. PRACTICAL APPLICATIONS: The finding of this research may serve as a basis for the subsequent development of walnut diaphragm into instant tea-based health food or added to other food carriers to achieve auxiliary antioxidant and hypoglycemic effects. This study revealed that polyphenolic components were the material basis for the antioxidant and hypoglycemic effects of walnut diaphragm, which could be identified as landmark chemical components for controlling quality standards in the development of walnut diaphragm, thus accelerating the research process of quality standards for walnut diaphragm-related products. Furthermore, the studies on the mechanism of hypoglycemic activity supply more credible data to support the development of walnut diaphragm into a safe and consumer-friendly health food. With abundant resources and clear efficacy, walnut diaphragm has great development prospect and application value.
Topics: Antioxidants; Juglans; Hypoglycemic Agents; Diaphragm; Molecular Docking Simulation; Kinetics; Plant Extracts; Phenols; alpha-Amylases
PubMed: 36121702
DOI: 10.1111/jfbc.14403 -
BMC Medical Imaging Feb 2022To clarify the differences in diaphragm thickness between male and female participants in healthy young adults with ultrasonography using the mean intima media thickness...
BACKGROUND
To clarify the differences in diaphragm thickness between male and female participants in healthy young adults with ultrasonography using the mean intima media thickness (IMT) method and to investigate the relationship between diaphragm thickness and respiratory pressure.
METHODS
Twenty-nine healthy individuals (16 females and 13 males) participated in the study. Diaphragm thickness was measured at total lung capacity (TLC) and at functional residual capacity (FRC) in each participant. We measured the diaphragm thickness using a method for mean intima media thickness. Moreover, change ratio of diaphragm thickness was calculated with the diaphragm thickness at TLC and FRC.
RESULTS
Mean diaphragm thicknesses at FRC in males were significantly narrower than those in females (p < 0.001). The change ratio of diaphragm thickness was significantly augmented in males compared with that in females (p < 0.001). There was a positive correlation between the change ratio of diaphragm thickness and pulmonary function data and respiratory muscle strength in healthy young adults.
CONCLUSIONS
The change ratio of diaphragm thickness using the IMT method can be accurately performed with a high degree of reproducibility by clinical laboratory technicians and may be a useful indicator for evaluating diaphragm muscle strength.
Topics: Adult; Carotid Intima-Media Thickness; Diaphragm; Female; Functional Residual Capacity; Healthy Volunteers; Humans; Male; Sex Factors; Total Lung Capacity; Ultrasonography; Young Adult
PubMed: 35148697
DOI: 10.1186/s12880-022-00748-y