The experiences of medical and pharmacy students participating in a collaborative online international learning on social accountability and global health: a qualitative study.

BACKGROUND: Social accountability aims to promote a collective ethic that upholds the fundamental values of equity, efficiency, solidarity, and social justice in healthcare and is now considered as a critical mission of academic health centers. Collaborative Online International Learning (COIL) is a pedagogical approach that uses digital technology to provide experiential international learning, specifically for increasingly diverse and multicultural healthcare work environments. The SOLID'AIRS program is an innovative French-language COIL that aims to set up international exchanges and workshops on social accountability between health sciences students. The aim of our study was to assess the impact of participation in the SOLID'AIRS program on medical and pharmacy students. METHOD: Five universities in four different countries were involved in SOLID'AIRS. We conducted a qualitative study by performing individual, semi-directed interviews with students who participated in the program from 2021 to 2022. A thematic analysis was conducted in five chronological phases: (1) reading, (2) descriptive coding, (3) conceptual coding, (4) identification of themes and (5) production of a coherent thematic structure. RESULTS: After including sixteen student participants, 13 medical and 3 pharmacy students, we identified four main themes related to the impact of participation: (1) previous experiences in social accountability and international learning, (2) perception of the program, (3) perceived impacts of the program, and (4) difficulties encountered and avenues to improve the program. Overall, the program was well received by all participants who reported the advantages and limitations of the online learning format. The primary advantage of this format was its feasibility. The participants noted both professional and personal benefits of the program for their current and future practice, including greater reflexivity towards health sciences practice. Based on the challenges faced during the program, particularly in coordinating group work and communication, participants suggested increased supervision of group projects by collaborators, and organizing at least one in-person meeting for future editions. The participants reported encountering difficulties during the COIL and suggested ways of improvement. CONCLUSION: Participating in a COIL on social accountability appears to be an effective way to adopt a reflective approach to medical practice and should be implemented and evaluated in other educational contexts.

Reversal of Fetal Compromise Following In Utero Treatment of Vein of Galen Malformation Using Glue.

OBJECTIVE: To treat the fetus presenting with in utero compromise due to a large vein of Galen malformation (VOGM) using glue embolization. METHODS: The fetus that was referred for termination of pregnancy at 30 weeks of gestation due to severe cardiomegaly, mild pericardial effusion and large VOGM was evaluated using ultrasound. There was reversed end diastolic flow in the umbilical artery Doppler indicating imminent fetal demise in the premature fetus weighing <1200 g. Considering the request of parents, a treatment similar to recently reported cases of VOGM embolization in utero was attempted as an emergency procedure to salvage the baby. Due to unavailability of coils, financial constraints and urgent need for intervention, n-butyl cyanoacrylate glue with lipiodol was used to embolize the venous outflow of VOGM outflow under ultrasonographic guidance. RESULTS: There was immediate correction of the umbilical artery Doppler waveform with the establishment of a normal flow pattern. The cardiomegaly resolved over 3 weeks and fetal MRI done 2 weeks later showed normal brain architecture with no evidence of hemorrhage or infarction. Pregnancy was continued for 4 weeks after the procedure and terminated at 36 weeks. A female baby weighing 1900 g was delivered by Cesarean section with an Apgar of 8/10. Though initially the baby did well, with mild ventriculomegaly reported on postnatal day 5, she eventually presented at 3 months of age with cardiac failure. As the MRI showed encephalomalacia, due to uncertainty of neurological outcome, further treatment was not pursued by the parents and the baby died a few days later. CONCLUSION: To our knowledge, this is the first report on the use of glue to treat VOGM prenatally. Though technically successful in correcting the in utero compromise, the baby eventually expired. Cases of in utero embolization using coils and glue have shown success in reversing prenatal pathology and improving survival. However, long-term outcomes including neurological status are yet to be reported.

The cohesin ATPase cycle is mediated by specific conformational dynamics and interface plasticity of SMC1A and SMC3 ATPase domains.

Cohesin is key to eukaryotic genome organization and acts throughout the cell cycle in an ATP-dependent manner. The mechanisms underlying cohesin ATPase activity are poorly understood. Here, we characterize distinct steps of the human cohesin ATPase cycle and show that the SMC1A and SMC3 ATPase domains undergo specific but concerted structural rearrangements along this cycle. Specifically, whereas the proximal coiled coil of the SMC1A ATPase domain remains conformationally stable, that of the SMC3 displays an intrinsic flexibility. The ATP-dependent formation of the heterodimeric SMC1A/SMC3 ATPase module (engaged state) favors this flexibility, which is counteracted by NIPBL and DNA binding (clamped state). Opening of the SMC3/RAD21 interface (open-engaged state) stiffens the SMC3 proximal coiled coil, thus constricting together with that of SMC1A the ATPase module DNA-binding chamber. The plasticity of the ATP-dependent interface between the SMC1A and SMC3 ATPase domains enables these structural rearrangements while keeping the ATP gate shut. VIDEO ABSTRACT.

The oncogenic fusion protein EML4-NTRK3 requires three salt bridges for stability and biological activity.

Aim of study: Chromosomal translocations involving neurotrophic receptor tyrosine kinases (NTRKs) have been identified in 20 % of soft tissue sarcomas. This work focuses on the EML4-NTRK3 translocation identified in cases of Infantile Fibrosarcoma, which contains the coiled-coil multimerization domain of Echinoderm Microtubule-like protein 4 (EML4) fused with the tyrosine kinase domain of Neurotrophic Receptor Tyrosine Kinase 3 (NTRK3). The aim of the study was to test the importance of tyrosine kinase activity and multimerization for the oncogenic activity of EML4-NTRK3. Methods: These studies examined EML4-NTRK3 proteins containing a kinase-dead or WT kinase domain, together with mutations in specific salt bridge residues within the coiled-coil domain. Biological activity was assayed using focus assays in NIH3T3 cells. The MAPK/ERK, JAK/STAT3 and PI3K/AKT pathways were analyzed for downstream activation of signaling pathways. Localization of EML4-NTRK3 proteins was examined by immunofluorescence microscopy, and the ability of the EML4 coiled-coil domain to drive protein multimerization was examined by biochemical assays. Results: Activation of EML4-NTRK3 relies on both the tyrosine kinase activity of NTRK3 and salt-bridge stabilization within the coiled-coil domain of EML4. The tyrosine kinase activity of NTRK3 is essential for the biological activation of EML4-NTRK3. Furthermore, EML4-NTRK3 activates downstream signaling pathways MAPK/ERK, JAK/STAT3 and PKC/PLCγ. The disruption of three specific salt bridge interactions within the EML4 coiled-coil domain of EML4-NTRK3 blocks downstream activation, biological activity, and the ability to hetero-multimerize with EML4. We also demonstrate that EML4-NTRK3 is localized in the cytoplasm and fails to associate with microtubules. Concluding statement: These data suggest potential therapeutic strategies for Infantile Fibrosarcoma cases bearing EML4-NTRK3 fusion through inhibition of salt bridge interactions and disruption of multimerization.

Soft Electromagnetic Sliding Actuators for Highly Compliant Planar Motions Using Microfluidic Conductive Coil Array.

We propose a soft electromagnetic sliding actuator that provides various planar motions to construct highly compliant actuation systems. The actuator is composed of a fully soft actuation base (stator) for generating electromagnetic and magnetic forces and a rigid neodymium magnet (slider) that slides on the actuation base. A parallel liquid-metal coil array in the stator is designed based on theoretical modeling and an optimization process to maximize the electromagnetic field density. The stretchable magnetic components in the stator allow the slider to retain its position stably without additional constraints. By incorporating an untethered structure in which the slider is mechanically decoupled from the stator, the actuator can be operated with reduced power consumption, attributed to the absence of a restoring force. The trajectory of the slider can be programmed by selectively applying the input current to the liquid-meal coil array, and the location of the slider can be estimated by measuring the change in inductance of each coil. Moreover, the proposed actuator demonstrates the capability of operating on curved surfaces through its physical compliance as well as on inclined surfaces thanks to the holding force generated by the magnetic components of the stator. Taking advantage of the unique characteristics of our actuator, robotic applications, including shape morphing systems and sensor-actuator integrated systems, are demonstrated.

A 32-channel high-impedance honeycomb-shaped receive array for temporal lobes exploration at 11.7T.

PURPOSE: The newly operational 11.7T Iseult scanner provides an improved global SNR in the human brain. This gain in SNR can be pushed even further locally by designing region-focused dense receive arrays. The temporal lobes are particularly interesting to neuroscientists as they are associated with language and concept recognition. Our main goal was to maximize the SNR in the temporal lobes and provide high-acceleration capabilities for fMRI studies. METHODS: We designed and developed a 32-channel receive array made of non-overlapped hexagonal loops. The loops were arranged in a honeycomb pattern and targeted the temporal lobes. They were placed on a flexible neoprene cap closely fitting the head. A new stripline design with a high impedance was proposed and applied for the first time at 11.7T. Specific homebuilt miniaturized low-impedance preamplifiers were directly mounted on the loops, providing preamplifier decoupling in a compact and modular design. Using an anatomical phantom, we experimentally compared the SNR and parallel imaging performance of the region-focused cap to a 32-channel whole-brain receive array at 11.7T. RESULTS: The experimental results showed a 1.7-time higher SNR on average in the temporal lobes compared to the whole brain receive array. The g-factor is also improved when undersampling in the antero-posterior and head-foot directions. CONCLUSION: A significant SNR boost in the temporal lobes was demonstrated at 11.7T compared to the whole-brain receive array. The parallel imaging capabilities were also improved in the temporal lobes in some acceleration directions.

Advancements in MR hardware systems and magnetic field control: B0 shimming, RF coils, and gradient techniques for enhancing magnetic resonance imaging and spectroscopy.

High magnetic field homogeneity is critical for magnetic resonance imaging (MRI), functional MRI, and magnetic resonance spectroscopy (MRS) applications. B0 inhomogeneity during MR scans is a long-standing problem resulting from magnet imperfections and site conditions, with the main issue being the inhomogeneity across the human body caused by differences in magnetic susceptibilities between tissues, resulting in signal loss, image distortion, and poor spectral resolution. Through a combination of passive and active shim techniques, as well as technological advances employing multi-coil techniques, optimal coil design, motion tracking, and real-time modifications, improved field homogeneity and image quality have been achieved in MRI/MRS. The integration of RF and shim coils brings a high shim efficiency due to the proximity of participants. This technique will potentially be applied to high-density RF coils with a high-density shim array for improved B0 homogeneity. Simultaneous shimming and image encoding can be achieved using multi-coil array, which also enables the development of novel encoding methods using advanced magnetic field control. Field monitoring enables the capture and real-time compensation for dynamic field perturbance beyond the static background inhomogeneity. These advancements have the potential to better use the scanner performance to enhance diagnostic capabilities and broaden applications of MRI/MRS in a variety of clinical and research settings. The purpose of this paper is to provide an overview of the latest advances in B0 magnetic field shimming and magnetic field control techniques as well as MR hardware, and to emphasize their significance and potential impact on improving the data quality of MRI/MRS.

A Rare Case of Ruptured Distal Posterior Cerebral Artery Aneurysm Followed by Middle Cerebral Artery Occlusion due to Delayed Diagnosis of Infective Endocarditis.

A 31-year-old female presented to our hospital with sudden headache and altered consciousness. Computed tomography showed left acute subdural hematoma, and digital subtraction angiography revealed a small aneurysm on the left distal posterior cerebral artery. Coil embolization was conducted, and the patient was discharged with no neurological deficits. However, two weeks later, she presented with complete left hemiplegia and with the National Institutes of Health Stroke Scale of 20. Magnetic resonance angiography showed the occlusion of right middle cerebral artery, and the Diffusion-Weighted Imaging-Alberta Stroke Program Early Computed Tomography Score was four. Mechanical thrombectomy was conducted. Complete recanalization was achieved, and the patient recovered favorably. Although she showed no symptoms of infection such as fever throughout the treatment of aneurysm and thrombectomy, her blood culture was positive for streptococcus mitis. Furthermore, the thrombus retrieved by thrombectomy showed bacterial mass, and transesophageal echocardiography (TEE) showed vegetation on the mitral valve that could not be detected by transthoracic echocardiography. Therefore, the patient was diagnosed with infective endocarditis (IE). She was administered penicillin for 6 weeks and was discharged with no neurological deficits. When treating young patients with small aneurysms in rare locations, IE should be suspected, and blood culture and TEE should be conducted, even when there are no obvious symptoms of systemic infection.

Peptide Bundlemer Networks or Lattices: Controlling Cross-Linking and Self-Assembly Using Protein-like Display of Chemistry.

Coiled-coil 'bundlemer' peptides were selectively modified with allyloxycarbonyl (alloc)-protected lysine, a non-natural amino acid containing an alkene on its side chain. The specific display of this alkene from the coiled-coil surface with protein-like specificity enabled this residue to be used as a covalent linkage for creating peptide networks with controllable properties or as a physical linkage for the self-assembly of bundlemers into unexpected, intricate lattices driven by the hydrophobic nature of the side chain. For network formation, peptides were modified with both alloc-protected lysine and cysteine amino acids for solution assembly into solvent-swollen films and subsequent covalent cross-linking via thiol-ene photo click reactions. The degree of network cross-linking, as determined by rheometry, was finely tuned by varying the specific spatial display of reactive groups on the bundlemer building block particles, transitioning between intrabundle and interbundle cross-linking. The designed display of alloc groups from the center of the bundlemer building block also prompted particle self-assembly into an unexpected intricate lattice with a porous morphology. The lattices were studied in a variety of solution conditions using transmission electron microscopy, cryotransmission electron microscopy, and small-angle X-ray scattering. The approximate particle arrangement in the lattice was determined by using coarse-grained modeling and machine learning optimization techniques along with experimental methods. The proposed truss-like face-centered cubic packing of the alloc-functionalized bundlemers agrees well with the experimental results.

Insertable, dual-density dielectric barrier for acoustic pressure level reduction in high-performance human head-only MRI system.

We report use of a dual-density dielectric barrier surrounding a detachable high-pass radiofrequency (RF) birdcage coil to achieve an order-of-magnitude reduction of acoustic noise in a high-performance head gradient system. The barrier consisted of a 4.5 mm-thick mass-loaded vinyl and a 6 mm-thick polyurethane foam. It was inserted into the radial gap between the birdcage coil and the RF shield in a prototype head-only gradient system at 3 T. More than 9 dBA reduction of sound pressure level was achieved on the average with representative, high acoustic-noise imaging sequences. Increased acoustic damping was apparent from acoustic impulse response functions. High dielectric constant of the mass-loaded vinyl effectively added distributed capacitance to the birdcage coil, lowering the resonance frequency, but not seriously degrading the RF transmission performance. The barrier occupied the radial space normally used for air cooling of the RF coil and the RF shield. The resulting omission of air cooling was found to be acceptable with efficient gradient thermal management and use of a high-resistivity RF shield for eddy current reduction. The proposed method can improve patient experience while preserving image quality in a high-power head-only gradient system.

Drill turn technique for enhanced visualization of wide-neck bifurcation aneurysms in Y-stent-assisted coiling with LVIS EVO stents: technical considerations and mid-term results.

BACKGROUND: Crossing Y-stent-assisted coiling (CYSAC) is a feasible yet technically challenging technique for the treatment of wide-neck bifurcation aneurysms (WNBAs). OBJECTIVE: To present mid-term results of Y-stent-assisted coiling (YSAC) using the LVIS EVO stent and to describe our "drill turn" technique for stent crossing. METHODS: This retrospective, observational study included 37 consecutive patients treated with YSAC using LVIS EVO stents at five centres between September 2020 and March 2023. RESULTS: Immediately after treatment, 31 of the 37 patients (83.8%) achieved Raymond-Roy occlusion classification (RROC) Class I occlusion, while 5 patients (13.5%) had Class II and 1 patient (2.7%) had Class III occlusion. The mean follow-up period was 32.8 months (range: 11-41 months), and all patients underwent follow-up imaging after ≥ 6 months. On follow-up imaging, 34 patients (92%), including all those with immediate RROC Class I occlusion, 2 with Class II, and 1 with Class III, showed Class I occlusion. One patient with RROC Class II occlusion demonstrated a gradual decrease in residual filling, while one large partially thrombosed middle cerebral artery aneurysm and one large basilar tip aneurysm (8%) with residual neck filling remained unchanged on the 6-month digital subtraction angiograph. CONCLUSION: Utilizing the described drill turn technique, CYSAC with LVIS EVO stents was found to be feasible and safe for WNBA treatment, with high and stable occlusion rates observed during mid-term follow-up.

A Case of Coil-Assisted Retrograde Transvenous Obliteration to Treat Colonic Varices.

Colonic variceal bleeding is a rare cause of lower gastrointestinal (GI) bleeding, which carries a high mortality rate. Due to limited data, the optimal management of colonic variceal bleeding is not known. Coil-assisted retrograde transvenous obliteration (CARTO) has been shown to be very effective in managing non-esophageal variceal bleeding, but only a few cases demonstrate its effectiveness in treating colonic variceal bleeding. Here we present a case of colonic variceal bleeding treated with CARTO in order to expand on the limited body of evidence showing its efficacy in effectively treating this rare cause of life-threatening GI bleeding.

Successful stent-assisted coil embolization for a recurrent distal posterior inferior cerebellar artery aneurysm: A case presentation.

Background: Distal posterior inferior cerebellar artery (PICA) aneurysms are exceedingly rare intracranial aneurysms. In the acute phase of rupture, interventions commonly involve parent artery occlusion through endovascular treatment or direct trapping surgery. There is no consensus on the best treatment of chronic ruptured or unruptured aneurysms, and stent-assisted coil embolization has not yet been reported in the chronic phase of rupture. Case Description: We present a case of a 46-year-old female with a recurrent distal PICA aneurysm at 18 months following the initial treatment for subarachnoid hemorrhage and was treated by stent-assisted coil embolization with Neuroform Atlas (Stryker, USA), with a favorable outcome. Conclusion: Distal PICA aneurysms occur at the apical curvature, where primitive arterial anastomoses existed during development, pointing to the potential vulnerability of the vessel wall at these sites. Stent-assisted coil embolization has shown effectiveness in preserving the parent artery for chronic ruptured and unruptured distal PICA aneurysms. Nonetheless, the narrowness and tortuosity of the PICA present obstacles to treatment. In our case, the procedure was feasible utilizing the Neuroform Atlas (Stryker, USA) with the Transcell approach. A thorough grasp of the characteristics of stents and their application is pivotal for achieving effective treatment outcomes.

Grouting technique-combining transvenous Onyx and coils for the embolization of complex non-cavernous intracranial dural arteriovenous fistulas.

Objective: Incomplete occlusion of cerebral dural arteriovenous fistula (DAVF) may lead to fistula recurrence and rebleeding, which may necessitate several embolizations and lead to worse clinical outcomes. Herein, we describe a grouting technique for endovascular embolization and its outcomes in a series of patients with complex intracranial DAVF. Methods: A total of 20 patients with aggressive type or symptomatic intracranial non-cavernous DAVF underwent endovascular transvenous embolization combining detachable coils and Onyx. Two microcatheters were positioned either in the distal segment of the involved sinus or near the draining veins. To achieve tight occlusion of the involved sinus, coils were carefully delivered through the first microcatheter, starting from the distal segment and then to the proximal segment. Next, Onyx was injected through the second microcatheter to reinforce and fill (grout) the interspace of coil mass and gradually refluxed to the mural channels and para-sinus cortical veins until the fistula was completely occluded. Results: Successful embolization was achieved in all 20 patients. The initial angiographic results revealed the achievement of complete occlusion in 19 patients (95%). At the postembolization follow-up, complete obliteration of the fistula was achieved in all patients (100%). No symptom or angiographic recurrence was observed at the 2- to 5-year follow-ups. No patient required additional embolization or stereotactic radiosurgery. Conclusion: The proposed grouting technique combining detachable coils and Onyx appears to be promising for the elimination of complex intracranial non-cavernous DAVFs.

A Case of Traumatic Splenic Arteriovenous Fistula Treated by Transcatheter Arterial Embolization.

Transcatheter arterial embolization (TAE) has increasingly replaced surgery for treating solid organ injuries, including the spleen, due to its minimally invasive approach. Studies show only a 3% splenectomy rate after TAE, despite a 10% incidence of missed vascular injuries in the American Association for the Surgery of Trauma (AAST) grade III splenic injuries on initial computed tomography (CT) scans. However, there's a lack of high-quality studies recommending specific CT follow-up intervals after non-operative management (NOM) of splenic injuries or guidelines for initiating treatment in cases of pseudoaneurysms or arteriovenous fistulas (AVFs). Here, we discuss the case of a 44-year-old man who presented with a splenic injury due to a motor vehicle accident. The splenic injury was AAST-spleen grade III, but because there was no evidence of extravascular leakage or AVF formation, NOM was selected. CT on the fifth day showed a pseudoaneurysm and an AVF, for which TAE was performed on the seventh day, preserving most of the parenchyma of the spleen with no complications. The indications for NOM as a treatment strategy for splenic injury are expanding, but since the 2018 revision of the AAST grading, the grade changes depending on the presence or absence of vascular injury, but in some cases, it is difficult to determine the presence or absence of active bleeding by CT findings. In fact, it has been reported that more than 25% of vascular lesions do not show up on CT, although CT has good sensitivity in detecting active bleeding, and the rate of NOM failure is higher in AAST grade III and above, so early angiography is likely to be useful. Splenic AVF may present with few symptoms in the early stages but may present with extrahepatic portal hypertension in the late stages, and patients may present to the hospital with symptoms such as abdominal pain and diarrhea. TAE is often the treatment of choice in traumatic cases, and the extent of embolization is important in the balance between preserving splenic function and completing treatment. The shift towards conservative management of splenic trauma may increase the occurrence of splenic AVFs. Transcatheter coil embolization of segmental branches has been effective in treating posttraumatic splenic AVFs, preserving splenic immune function and reducing risks linked to surgery and splenectomy.

Part 1: Pushing the boundaries of neurointerventional surgery: A historical review of the work of Dr Gerard Debrun.

French-American neurointerventionalist and pioneer, Dr Gerard Debrun, laid the groundwork for treatments which have become irreplaceable in neurointerventional surgery today. This article aims to outline the career of Dr Debrun while highlighting his accomplishments and contributions to the field of neurointerventional surgery. We selected relevant articles from PubMed authored or co-authored by Dr Debrun between 1941 and 2023. All included articles discuss the accomplishments and contributions of Dr Debrun. Dr Debrun began his career in France by investigating neurointerventional techniques, most notably the intravascular Detachable Balloon Catheter (DBC). His work was recognized by renowned neurosurgeon Dr Charles Drake, who recruited him to London, Ontario. Dr Debrun created the foundation for homemade manufacturing of DBCs, building on one of the largest series for use of DBCs in cerebrovascular disease. Dr Debrun spent time as faculty at Massachusetts General Hospital (MGH) and Johns Hopkins Hospital, before arriving at the University of Illinois Chicago (UIC) where he remained until his retirement. Dr Debrun's subsequent contributions included the calibrated-leak balloon catheter, pioneering of glue embolization, setting the foundation for preoperative AVM embolizations, and as an early adopter of the Guglielmi detachable coil (GDC), including mastering the balloon remodeling technique for wide neck aneurysms. Dr Debrun established the first integrated neurointerventional surgery program at UIC, establishing a well sought-after fellowship program. Dr Debrun lectured extensively and was a prolific writer on neurointerventional surgery throughout this career. His contributions established the foundation for several techniques which have since become standard practice in present-day neurointerventional surgery.

Endoscopic ultrasound-guided treatment of isolated gastric varices entwined with arteries: A case report.

BACKGROUND: Interventional endoscopic ultrasound is clinically used for the treatment of isolated gastric varices (IGVs) owing to its precise visualization. CASE SUMMARY: A 39-year-old man was diagnosed with a large IGV during a routine physical examination. Endoscopic ultrasonography showed gastric varices entwined with an artery, which greatly increased the difficulty of treatment. We successfully treated the patient with endoscopic ultrasonography-guided coil embolization combined with cyanoacrylate injection. CONCLUSION: Endoscopic ultrasonography-guided coil embolization combined with cyanoacrylate injection was safe and effective for the treatment of an IGV entwined with an artery.

Design of a volumetric cylindrical coil-tuned at 298 MHz for 7 T imaging.

The concept of a 2D cylindrical High Pass Ladder (2D c-HPL) is used in the development of this ultra high radio frequency (UHRF) volumetric head coil for 7T tuned at the Larmor frequency of 298 MHz. The architecture of the 2D c-HPL helps to overcome the challenges associated with non-uniform magnetic field distribution. The prototype consists of an individual resonating array of inductance-capacitance (LC) elements and each component is tuned to the precise f o frequency. The tuning of the (i) inductance, (ii) capacitance, (iii) mesh size, and (iv) coupling coefficient play critical roles to attain the desired Larmor frequency. For this proof-of-concept, the prototype of a volumetric head coil consists of a cylindrical array size of 4 ×6, with individual LC components of inductance magnitude, 98 nH and four fixed value capacitors and one tunable capacitor that allowed to achieve the desired precession frequency, f r = 298 M H z . The model was tested for three different f o values of 269 MHz, 275 MHz and 286 MHz. The mutual coupling and the eigenfrequencies were compared through bench testing and dispersion equation. The experimental data were in good agreement (< 5%) with the theoretical eigenfrequencies from the dispersion relation. The theoretical eigenfrequencies and the experimental eigenfrequencies are in good agreement for eigenmodes (1,2), (1,3), (2,2), (2,3) and (4,3).

[Mechanism of Liangfang Wenjing Decoction in treatment of hypoxia on endometriosis with cold coagulation and blood stasis by regulating CHCHD4 expression].

To explore the mechanism of Liangfang Wenjing Decoction regulating coiled-coil-helix coiled-coil-helix domain containing 4(CHCHD4) in the treatment of hypoxia on endometriosis(EMs) with cold coagulation and blood stasis. The rat model of cold coagulation and blood stasis syndrome was prepared by the ice-water bath method, and then the EMs model was established by autologous intimal transplantation. The rats were randomly divided into model group, low, medium, and high(4.7, 9.4, and 18.8 g·kg~(-1)) dose groups of Liangfang Wenjing Decoction, Shaofu Zhuyu Decoction group, and sham group, with 10 rats in each group. The rats were given intragastric administration for four weeks. During the modeling, the general condition and vaginal smear of rats were observed, and the blood flow of ears and uterus were detected by laser speckle contrast imaging(LSCI) to judge the syndrome of cold coagulation and blood stasis. After the administration, the general condition of the rats was observed, and the area of ectopic lesions was measured by caliper. The localization and expression of CHCHD4 and hypoxia inducible factors-1α(HIF-1α) were detected by immunohistochemistry, and the mRNA and protein expressions of CHCHD4 and HIF-1α were detected by real-time quantitative polymerase chain reaction(RT-qPCR) and Western blot. The primary culture of ectopic endometrial stromal cells(ESCs) from EMs patients was performed, and the CHCHD4 overexpression plasmid was constructed and transfected to establish the ESCs model of CHCHD4 overexpression. The cells were divided into the control group, CHCHD4 overexpression group, CHCHD4 overexpression+control serum group, and CHCHD4 overexpression+Liangfang Wenjing Decoction serum group. The protein expression of CHCHD4 and HIF-1α was detected by Western blot, and the glucose consumption and lactic acid level were detected. The cell proliferation was detected by MTT assay. The experiment found that compared with normal rats, the modeling rats showed symptoms of cold coagulation and blood stasis, such as mental malaise, reduced diet and drinking water, disordered estrous cycle, and blocked blood circulation in ears and uterine microvessels. Compared with the sham group, the ectopic lesions in the model group were uplifted, and the mRNA and protein expressions of CHCHD4 and HIF-1α were significantly increased(P<0.05). Compared with the model group, the symptoms of cold coagulation and blood stasis in each treatment group were improved, and the area of ectopic lesions was significantly reduced(P<0.05 or P<0.01). The mRNA and protein expression levels of CHCHD4 and HIF-1α were significantly decreased(P<0.05 or P<0.01). In the cell model, compared with the control group, the expression of CHCHD4, HIF-1α protein, glucose consumption, lactic acid level, and cell proliferation activity in the CHCHD4 overexpression group were significantly increased(P<0.01). Compared with the CHCHD4 overexpression group, there was no significant change in each index in the control serum group, while the protein expression of CHCHD4 and HIF-1α in the Liangfang Wenjing Decoction serum group was decreased significantly(P<0.05 or P<0.01). The glucose consumption, lactic acid level, and cell proliferation activity decreased significantly(P<0.01). It can be seen from the above that the therapeutic effect of Liangfang Wenjing Decoction on EMs with cold coagulation and blood stasis might be related to reducing the expression of CHCHD4 and then improving the hypoxia of ectopic lesions and ectopic ESCs.