1.Homo-dimerization of RyR1 C-terminus via charged residues in random coils or in an alpha-helix.
Experimental & Molecular Medicine 2007;39(5):594-602
To investigate the mechanism by which the C-terminus (4,938-5,037) of the ryanodine receptor 1 (RyR1) homo-tetramerizes, forming a functional Ca2+ -release channel, the structural requirements for the tetramerization were studied using site-directed mutagenesis. Alanine-substitutions at five charged residues, E4976, H5003, D5026, E5033 and D5034, significantly decreased the formation of homo-dimers (reduced by > 50%). Interaction between the C-terminus and cytoplasmic loop I (4,821-4,835) required two positively charged residues, H4832 and K4835. Based on the predicted protein secondary structures, all seven charged residues are located in random coils. Paired alanine-substitutions at six negatively charged residues (E4942A/D4953A, D4945A/E4952A and E4948A/ E4955A) of the alpha-helix (4,940-4,956) in the C-terminus increased homo-dimerization. Therefore, the homo-tetramerization of RyR1 may be mediated by intra- and/or inter-monomer electrostatic interactions among the C-terminal charged residues in random coils or in an alpha-helix.
Amino Acid Sequence
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Animals
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Dimerization
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Models, Molecular
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Molecular Sequence Data
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Mutagenesis, Site-Directed
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Protein Structure, Quaternary
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Protein Structure, Secondary
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Rabbits
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Recombinant Fusion Proteins/chemistry/genetics
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Ryanodine Receptor Calcium Release Channel/*chemistry/genetics
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Sequence Homology, Amino Acid
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Static Electricity
2.Heart failure as the first manifestation of renal cell carcinoma.
Chee Meng LEE ; Allen SIM ; Gunasegaran KURUGULASIGAMONEY ; Lay Guat NG
Korean Journal of Urology 2015;56(1):82-85
We report the rare case of a patient with advanced renal cell carcinoma (RCC) who initially presented to the hospital with symptoms of cardiac failure. Preoperative cardiac studies did not reveal any underlying ischemia. After resection of a large 14-cm left renal tumor, cardiac function was noted to improve dramatically. We discuss this case of concomitant RCC and nonischemic cardiomyopathy.
Asian Continental Ancestry Group
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Carcinoma, Renal Cell/*diagnosis/surgery
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Cardiomyopathies/*diagnosis
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Female
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Heart Failure/*etiology
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Humans
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Middle Aged
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Paraneoplastic Syndromes/complications
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Thalassemia/complications
3.Description of Aedes (Aedimorphus) alboscutellatus occuring in Korea.
Kwan Woo LEE ; Allen N HUNT ; Philip E FLEICHER
The Korean Journal of Parasitology 1983;21(1):111-117
Aedes alboscutellatus was recorded first in Korea. This mosquito was collected near Demilitarized Zone of Korea Penninsula from 1979-1980. Its morphology and taxonomical position was described(abstracted from English content).
parasitology-arthropoda
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mosquito
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Aedes alboscutellatus
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morphology
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taxonomy
5.Psychotic Symptoms in Patients With Major Neurological Diseases
Jong S. KIM ; Seung-Bong HONG ; Keun-Woo PARK ; Allen T.C. LEE
Journal of Clinical Neurology 2024;20(2):153-165
Neurological diseases often manifest with neuropsychiatric symptoms such as depression, emotional incontinence, anger, apathy and fatigue. In addition, affected patients may also experience psychotic symptoms such as hallucinations and delusions. Various factors contribute to the development of psychotic symptoms, and the mechanisms of psychosis are similar, but still differ among various neurological diseases. Although psychotic symptoms are uncommon, and have been less well investigated, they may annoy patients and their families as well as impair the patients’ quality of life and increase the caregiver burden. Therefore, we need to appropriately identify and treat these psychotic symptoms in patients with neurological diseases.
6.Serosurveillance of Scrub Typhus in Small Mammals Collected from Military Training Sites near the DMZ, Northern Gyeonggi-do, Korea, and Analysis of the Relative Abundance of Chiggers from Mammals Examined.
Heung Chul KIM ; In Yong LEE ; Sung Tae CHONG ; Allen L RICHARDS ; Se Hun GU ; Jin Won SONG ; John S LEE ; Terry A KLEIN
The Korean Journal of Parasitology 2010;48(3):237-243
Comprehensive quarterly serosurveillance on scrub typhus in small mammals collected from military training sites located near the Demilitarized Zone (DMZ), northern Gyeonggi-do (Province), ROK was conducted to determine the potential rodent-borne and associated ectoparasite disease risks to military personnel. A total of 1,196 rodents and insectivores representing 8 species, Apodemus agrarius (87.3%, n = 1,044), Mus musculus (5.4%, n = 65), Crocidura lasiura (3.3%, n = 40), Microtus fortis (2.6%, n = 31), Micromys minutus (0.3%, n = 4), Tscherskia triton (0.3%, n = 4), Rattus norvegicus (0.3%, n = 4), and Myodes regulus (0.3%, n = 4) were assayed for the presence of antibodies to Orientia tsutsugamushi. O. tsutsugamushi antibodies were detected in 6 of 8 species and seroprevalence determined; A. agrarius (45.6%), M. musculus (23.1%), M. fortis (48.4%), M. minutus (50.0%), T. triton (50.0%), and R. norvegicus (25.0%). A total of 31,184 chigger mites collected from 508 rodents and insectivores were slide-mounted and 10 species belonging to 4 genera were identified. Leptotrombidium pallidum (53.4%) was the most frequently collected, followed by L. palpale (15.7%), Neotrombicula tamiyai (14.3%), L. orientale (10.7%), L. zetum (3.1%), Walchia fragilis (2.1%), and L. gemiticulum (0.8%), while the remaining 3 species, L. subintermedium, N. gardellai, and Euschoengastia koreaensis were rarely observed (prevalence < 10%). In contrast to previous surveys, higher chigger indices of the primary scrub typhus vectors, L. pallidum (165.4), L. orientale (45.0), and L. palpale (21.4), were observed during the spring season.
Animals
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Antibodies, Bacterial/immunology
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Arachnid Vectors/classification/*microbiology
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Disease Reservoirs/classification/microbiology/*parasitology
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Humans
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Military Facilities
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Orientia tsutsugamushi/*immunology/isolation & purification
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Republic of Korea
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Rodentia/classification/*immunology/microbiology/*parasitology
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Scrub Typhus/microbiology/*transmission/*veterinary
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Seroepidemiologic Studies
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Trombiculidae/classification/*microbiology
7.Endovascular Strategies in the Management of Acute Limb Ischemia
Benjamin LIND ; Omar MORCOS ; Hector FERRAL ; Allen CHEN ; Thomas AQUISTO ; Stephen LEE ; Cheong Jun LEE
Vascular Specialist International 2019;35(1):4-9
Acute limb ischemia (ALI) represents one of the most common emergent scenarios encountered by a vascular specialist. Despite expedient revascularization, high rates of limb loss are reported along with high mortality rates which are second only to ruptured abdominal aortic aneurysms. Surgical revascularization is standard of care. Endovascular techniques as an alternative have emerged to be appropriate first line therapy when addressing the threatened limb. We review the etiology and classification of ALI and current endovascular techniques and evidence to date in the management of patients acutely presenting with extremity ischemia.
Aortic Aneurysm, Abdominal
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Classification
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Embolism and Thrombosis
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Endovascular Procedures
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Extremities
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Humans
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Ischemia
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Mortality
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Peripheral Arterial Disease
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Specialization
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Standard of Care
8.Comparison of ultrasound-measured properties of the common carotid artery to tobacco smoke exposure in a cohort of Indonesian patients
Yu R. ALLEN ; Hasjim BIMA ; Yu E. LUKE ; Gabriel CHRISTOPHER ; Anshus ALEXANDER ; Lee B. JONATHAN ; Louthan J. MICHAEL ; Kim C. ESTHER ; Lee KATRINA ; Tse CHRISTINA ; Keown THOMAS ; Lahham SHADI ; Alvarado MAILI ; Bunch STEVEN ; Gari ABDULATIF ; Fox Christian J.
World Journal of Emergency Medicine 2017;8(3):177-183
BACKGROUND:The purpose of this study was to use point-of-care ultrasound (POCUS) to investigate the relationship between tobacco smoke exposure and the characteristics of the common carotid artery (CCA). The effect of both primary and secondary smoking on CCA properties was evaluated. METHODS:We performed a prospective cross-sectional study across 20 primary care clinics in Bandung, West Java, Indonesia in July 2016. Point of care ultrasound was performed on a convenience sample of Indonesian patients presenting to clinic. The CCA wall stiffness and carotid intima-media thickness (CIMT) were measured during diastole and systole. These measurements were correlated with smoke exposure and cardiovascular disease. RESULTS: We enrolled 663 patients in the study, with 426 patients enrolled in the smoking category and 237 patients enrolled in the second-hand smoke category. There was an overall positive correlation with the measured lifestyle factors and the ultrasound-measured variables in the group of individuals who smoked. For all variables, age seemed to contribute the most out of all of the lifestyle factors for the positive changes in CIMT and CCA wall stiffness. CONCLUSION:Our data yielded correlations between CCA properties and cardiovascular risk, as well as between CIMT and arterial stiffness. We were also able to demonstrate an increase in thickness of the CIMT in patients who have been exposed by tobacco through the use of ultrasound. Further large scale studies comparing patients with multiple cardiac risk factors need to be performed to confirm the utility of ultrasound findings of cardiovascular disease and stroke.
9.Evaluation of a point of care ultrasound curriculum for Indonesian physicians taught by first-year medical students
Lee B. JONATHAN ; Tse CHRISTINA ; Keown THOMAS ; Louthan MICHAEL ; Gabriel CHRISTOPHER ; Anshus ALEXANDER ; Hasjim BIMA ; Lee KATRINA ; Kim ESTHER ; Yu LUKE ; Yu ALLEN ; Lahham SHADI ; Bunch STEVEN ; Alvarado MAILI ; Gari ABDULATIF ; Fox C. JOHN
World Journal of Emergency Medicine 2017;8(4):281-286
BACKGROUND: The purpose of this study was to assess the short-term efficacy of a 4-week ultrasound curriculum taught by American first-year medical students to general practitioners working in public health care clinics, or puskesmas, in Bandung, Indonesia. METHODS: We performed a prospective, observational study of Indonesian health care practitioners from public clinics in Bandung, Indonesia. These practitioners were enrolled in a 4-week ultrasound training course taught by first-year American medical students. A total of six sessions were held comprising of 38 ultrasound milestones. A pre-course and post-course written exam and practical exam was taken by each participant. RESULTS: We enrolled 41 clinicians in the course. The average pre-course exam score was 35.2% with a 2.4% pass rate, whereas the average post-course exam score was 82.0% with a 92.7% pass rate. The average practical score at the completion of the course was 83.2% (SD=0.145) with 82.9% of the class passing (score above 75.0%). CONCLUSION: Our data suggests that first-year medical students can effectively teach ultrasound to physicians in Indonesia using a 4-week intensive ultrasound training course. Future studies are needed to determine the amount of training required for proficiency and to evaluate the physicians' perceptions of the student-instructors' depth of knowledge and skil in point of cаre ultrаsound.
10.Propagation Characteristics of Fasting Duodeno-Jejunal Contractions in Healthy Controls Measured by Clustered Closely-spaced Manometric Sensors
Jason R BAKER ; Joseph R DICKENS ; Mark KOENIGSKNECHT ; Ann FRANCES ; Allen A LEE ; Kerby A SHEDDEN ; James G BRASSEUR ; Gordon L AMIDON ; Duxin SUN ; William L HASLER
Journal of Neurogastroenterology and Motility 2019;25(1):100-112
BACKGROUND/AIMS: High-resolution methods have advanced esophageal and anorectal manometry interpretation but are incompletely established for intestinal manometry. We characterized normal fasting duodeno-jejunal manometry parameters not measurable by standard techniques using clustered closely-spaced recordings. METHODS: Ten fasting recordings were performed in 8 healthy controls using catheters with 3–4 gastrointestinal manometry clusters with 1–2 cm channel spacing. Migrating motor complex phase III characteristics were quantified. Spatial-temporal contour plots measured propagation direction and velocity of individual contractions. Coupling was defined by pressure peak continuity within clusters. RESULTS: Twenty-three phase III complexes (11 antral, 12 intestinal origin) with 157 (95% CI, 104–211) minute periodicities, 6.99 (6.25–7.74) minute durations, 10.92 (10.68–11.16) cycle/minute frequencies, 73.6 (67.7–79.5) mmHg maximal amplitudes, and 4.20 (3.18–5.22) cm/minute propagation velocities were recorded. Coupling of individual contractions was 39.1% (32.1–46.1); 63.0% (54.4–71.6) of contractions were antegrade and 32.8% (24.1–41.5) were retrograde. Individual phase III contractions propagated > 35 fold faster (2.48 cm/sec; 95% CI, 2.25–2.71) than complexes themselves. Phase III complexes beyond the proximal jejunum were longer in duration (P = 0.025) and had poorer contractile coupling (P = 0.025) than proximal complexes. Coupling was greater with 1 cm channel spacing vs 2 cm (P < 0.001). CONCLUSIONS: Intestinal manometry using clustered closely-spaced pressure ports characterizes novel antegrade and retrograde propagation and coupling properties which degrade in more distal jejunal segments. Coupling is greater with more closely-spaced recordings. Applying similar methods to dysmotility syndromes will define the relevance of these methods.
Catheters
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Fasting
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Intestines
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Jejunum
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Manometry
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Muscle Contraction
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Myoelectric Complex, Migrating
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Periodicity