Hypoxic methane oxidation coupled to denitrification in a membrane biofilm

Alrashed, Wael,Lee, Jangho,Park, Joonhong,Rittmann, Bruce E.,Tang, Youneng,Neufeld, Josh D.,Lee, Hyung-Sool Elsevier 2018 Chemical engineering journal Vol.348 No.-

<P><B>Abstract</B></P> <P>Methane oxidation coupled to denitrification (MOD) was tested in a membrane biofilm reactor (MBfR) using methane gas as the sole electron donor. Nitrate reduction to nitrite was rate limiting, and CH<SUB>4</SUB> was present in the effluent. Slow kinetics of methane oxidation by bacteria were the factors that led to slow kinetics and incomplete removals. <I>Methylocystaceae</I> contained the largest fraction (21%) of bacterial SSU rRNA genes, and Archaea were nearly absent. The functional metagenome included all the genes essential for aerobic methane oxidation (<I>pmo, mdh, mtdB, folD,</I> and <I>fdh</I>) and nitrate reduction to dinitrogen (<I>nap/nar, nir, nor</I> and <I>nos</I>), but not for reverse methanogenesis (<I>mcr</I>). The functional metagenome supports that <I>Methylocystaceae</I> conducted MOD in syntrophy with heterotrophic denitrifiers (e.g., <I>Comamonadaceae</I> and <I>Brucellaceae</I>), suggesting aerobic MOD. DO measurements, serum-bottle tests, and calculation of O<SUB>2</SUB> permeation bolster hypoxically aerobic MOD would mainly account for denitrification in the MBfR.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Nitrate removal increased by 85% in the methane-utilizing MBfR. </LI> <LI> Slow kinetics of MOD microorganisms caused methane leakage to liquid. </LI> <LI> Metagenome identified all genes essential for aerobic methane oxidation. </LI> <LI> <I>Methylocystaceae</I> and diverse denitrifiers conducted MOD syntrophically. </LI> </UL> </P>

Reproducibility of shear wave elastography among operators, machines, and probes in an elasticity phantom

Abdulaziz Ibrahim Alrashed,Abdulrahman M.Alfuraih 대한초음파의학회 2021 ULTRASONOGRAPHY Vol.40 No.1

Purpose: This study was aimed to investigate the reproducibility of shear wave elastography (SWE) among operators, machines, and probes in a phantom, and to evaluate the effect of depth of the embedded inclusions and the accuracy of the measurements. Methods: In vitro stiffness measurements were made of six inclusions (10, 40, and 60 kPa) embedded at two depths (1.5 cm and 5 cm) in an elastography phantom. Measurements were obtained by two sonographers using two ultrasound machines (the SuperSonic Imagine Aixplorer with the XC6-1, SL10-2 and SL18-5 probes, and the General Electric LOGIQ E9 with the 9L-D probe). Variability was evaluated using the coefficient of variation. Reproducibility was calculated using intraclass correlation coefficients (ICCs). Results: For shallow inclusions, low variability was observed between operators (range, 0.9% to 5.4%). However, the variability increased significantly for deep inclusions (range, 2.4% to 80.8%). The measurement difference between the operators was 1%-15% for superficial inclusions and 3%-43% for deep inclusions. Inter-operator reproducibility was almost perfect (ICC>0.90). The measurement difference between machines was 0%-15% for superficial inclusions and 38.6%-82.9% for deep inclusions. For superficial inclusions, the reproducibility among the three probes was excellent (ICC>0.97). The mean stiffness values of the 10 kPa inclusion were overestimated by 16%, while those of the 40 kPa and 60 kPa inclusions were underestimated by 42% and 48%, respectively. Conclusion: Phantom SWE measurements were only reproducible among operators, machines, and probes at superficial depths. SWE measurements acquired in deep regions should not be used interchangeably among operators, machines, or probes.

Salvage flow diverter stent across the posterior communicating artery for persistent retrograde filling of a giant internal carotid artery aneurysm after parent vessel occlusion

Manzoor Muhammad Usman,AlRashed Abdullah A.,Alghabban Fatimah A.,Alqahtani Sultan M.,Alturki Abdulrahman Y. 대한뇌혈관외과학회 2021 Journal of Cerebrovascular and Endovascular Neuros Vol.23 No.2

Giant internal carotid artery (ICA) aneurysms are complex vascular lesions which are difficult to treat with open as well as endovascular surgery. Parent vessel occlusion is a well-established treatment option for such aneurysms. However, there have been a few reported cases of ruptured aneurysms related to the persistent retrograde filling after parent vessel occlusion. We report a case which highlights the usage of the flow diverter stent as a potential treatment strategy for the management of retrograde filling of aneurysms. A 54-year-old female was found to have a giant left ICA aneurysm on a brain magnetic resonance imaging during workup for headaches. She underwent occlusion of the left ICA proximal to the aneurysm using multiple coils. However, follow up angiograms after 6 months and 2 years demonstrated persistent retrograde filling of the left ICA aneurysm through the posterior communicating (PCOM) artery. Eventually, she was successfully treated with a flow diverter stent across the PCOM artery into the distal ICA. Follow up angiogram after 6 months showed patent flow in the PCOM artery and the distal ICA. with complete occlusion of the aneurysm. Using a flow diverter stent after insufficient parent vessel occlusion for giant intracranial aneurysms may be a feasible treatment option and an addition to the neurovascular treatment armamentarium.

Ulnar artery access for intracranial mechanical thrombectomy procedure: A salvage option after failed trans-femoral and trans-radial access

Muhammad U Manzoor,Abdullah A. Alrashed,Ibrahim A. Almulhim,Sultan Alqahtani,Fahmi Al Senani 대한뇌혈관외과학회 2023 Journal of Cerebrovascular and Endovascular Neuros Vol.25 No.4

84 years old gentle man with past medical history of hypertension and diabetes presented with sudden onset right sided weakness and aphasia for two hours. Initial neurological assessment revealed National Institute of Health Stroke Scale (NIHSS) 17. Computed tomography (CT) scan demonstrated minimal early ischemic changes along left insular cortex with occlusion of left middle cerebral artery (MCA). Based on clinical and imaging findings, decision was made to perform mechanical thrombectomy procedure. Initially, right common femoral artery approach was utilized. However, due to unfavorable type-III bovine arch, left internal carotid artery could not be engaged via this approach. Subsequently, access was switched to right radial artery. Angiogram revealed small caliber radial artery, with larger caliber ulnar artery. Attempt was made to advance the guide catheter through the radial artery, however significant vasospasm was encountered. Subsequently, ulnar artery was accessed and successful thrombolysis in cerebral infarction (TICI) III left MCA reperfusion was achieved with a single pass of mechanical thrombectomy via this approach. Post procedure neurological examination demonstrated significant clinical improvement. Doppler ultrasound 48 hours after the procedure demonstrated patent flow in radial and ulnar arteries with no evidence of dissection.

Initial experience with Scepter Mini dual lumen balloon for embolization of cerebrovascular diseases

Muhammad U Manzoor,Ibrahim A. Almulhim,Abdullah A. Alrashed,Shorog Althubait,Abdulrahman Y. Alturki,Sultan M. Al-Qahtani 대한뇌혈관외과학회 2023 Journal of Cerebrovascular and Endovascular Neuros Vol.25 No.2

Objective: Endovascular treatment of cerebrovascular diseases is often challenging due to small caliber, tortuous distal vessels. Several devices and techniques have evolved to overcome these challenges. Recently, a low profile dual lumen microballoon catheter, specifically designed for distal navigation is employed for neurovascular procedures. Due to its recent advent, scarce data is available on clinical utility and safety of Scepter Mini. The aim of this case series is to report our initial experience with Scepter Mini in the management of various cerebrovascular diseases.Methods: All interventional neurovascular cases performed using Scepter Mini between January 2020 till April 2021 were included. Data regarding patient demographics, procedural details and complications was retrospectively collected from patient’s electronic medical record and procedure reports.Results: Total twelve embolization procedures were performed in eleven patients, including six brain arteriovenous malformation, two dural arteriovenous fistula, one vein of Galen malformation and three hyper-vascular glomus tumor embolizations. All procedures were successfully performed with adequate penetration of the embolic agent. Complete embolization was performed in six procedures, while intended partial embolization was performed in the rest of procedures. Scepter Mini was solely used in ten procedures, however in the other two embolization procedures it was used as an additional conjunct tool to complete the intended embolization. No balloon related complication was observed in any procedure.Conclusions: Scepter Mini dual lumen microballoon catheter is safe and feasible for delivery of liquid embolic agents for cerebrovascular embolization procedures.

프탈레이트와 대체 가소제의 노출 수준과 위해성평가

이인애,Holger M,Koch,인연철,이고운,Raid Alakeel,May Alrashed,Ramadhan,Tosepu,Erwin Azizi Jayadipraja,Kraichat Tantrakamapa,고영림,최경호 한국환경보건학회 2021 한국환경보건학회 학술대회 자료집 Vol.2021 No.1