1.Stem Cell and Exosome Therapy in Pulmonary Hypertension
Seyeon OH ; Ji-Hye JUNG ; Kyung-Jin AHN ; Albert Youngwoo JANG ; Kyunghee BYUN ; Phillip C. YANG ; Wook-Jin CHUNG
Korean Circulation Journal 2022;52(2):110-122
Pulmonary hypertension is a rare and progressive illness with a devastating prognosis. Promising research efforts have advanced the understanding and recognition of the pathobiology of pulmonary hypertension. Despite remarkable achievements in terms of improving the survival rate, reducing disease progression, and enhancing quality of life, pulmonary arterial hypertension (PAH) is not completely curable. Therefore, an effective treatment strategy is still needed. Recently, many studies of the underlying molecular mechanisms and technological developments have led to new approaches and paradigms for PAH treatment. Management based on stem cells and related paracrine effects, epigenetic drugs and gene therapies has yielded prospective results for PAH treatment in preclinical research. Further trials are ongoing to optimize these important insights into clinical circumstances.
2.Development of a new biomechanical indicator for primary blast-induced brain injury.
Feng ZHU ; Cliff-C CHOU ; King-H YANG ; Albert-I KING
Chinese Journal of Traumatology 2015;18(1):10-12
Primary blast-induced traumatic brain injury (bTBI) has been observed at the boundary of brain tissue and cerebrospinal fluid (CSF). Such injury can hardly be explained by using the theory of compressive wave propagation, since both the solid and fuid materials have similar compressibility and thus the intracranial pressure (ICP) has a continuous distribution across the boundary. Since they have completely different shear properties, it is hypothesized the injury at the interface is caused by shear wave. In the present study, a preliminary combined numerical and theoretical analysis was conducted based on the theory of shear wave propagation/reflection. Simulation results show that higher lateral acceleration of brain tissue particles is concentrated in the boundary region. Based on this fnding, a new biomechanical vector, termed as strain gradient, was suggested for primary bTBI. The subsequent simple theoretical analysis reveals that this parameter is proportional to the value of lateral acceleration. At the boundary of lateral ventricles, high spatial strain gradient implies that the brain tissue in this area (where neuron cells may be contained) undergo significantly different strains and large velocity discontinuity, which may result in mechanical damage of the neuron cells.
Biomechanical Phenomena
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Blast Injuries
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etiology
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physiopathology
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Brain Injuries, Traumatic
;
etiology
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physiopathology
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Compressive Strength
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Computer Simulation
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Finite Element Analysis
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Humans
3.Altered Doppler flow patterns in cirrhosis patients: an overview.
Pooya IRANPOUR ; Chandana LALL ; Roozbeh HOUSHYAR ; Mohammad HELMY ; Albert YANG ; Joon Il CHOI ; Garrett WARD ; Scott C GOODWIN
Ultrasonography 2016;35(1):3-12
Doppler ultrasonography of the hepatic vasculature is an integral part of evaluating precirrhotic and cirrhotic patients. While the reversal of the portal venous flow is a well-recognized phenomenon, other flow patterns, although not as easily understood, may play an important role in assessing the disease status. This article discusses the different characteristic flow patterns observed from the portal vein, hepatic artery, and hepatic vein in patients with liver cirrhosis or related complications and procedures. Knowledge of these different flow patterns provides additional information that may reinforce the diagnosis of cirrhosis, help in staging, and offer prognostic information for determining the direction of therapy. Doppler ultrasonography is invaluable when liver transplantation is being considered and aids in the diagnosis of cirrhosis and portal hypertension.
Diagnosis
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Fibrosis*
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Hepatic Artery
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Hepatic Veins
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Humans
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Hypertension, Portal
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Liver Cirrhosis
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Liver Transplantation
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Portal Vein
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Ultrasonography, Doppler
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Ultrasonography, Doppler, Color
4.Revascularization of Concurrent Renal and Cerebral Artery Stenosis in a 14-Year-Old Girl with Takayasu Arteritis and Moyamoya Syndrome.
Meng Luen LEE ; Ming Yuh CHANG ; Tung Ming CHANG ; Rei Cheng YANG ; Ming Che CHANG ; Albert D YANG
Journal of Korean Medical Science 2018;33(10):e76-
Concurrent involvement of bilateral renal and cerebral arteries, usually incurred as stenosis, is rare in childhood-onset Takayasu arteritis (c-TA). We report the case of a 14-year-old girl, with c-TA, presenting with transient ischemic attack after endovascular revascularization for renal artery stenosis and cerebrovascular stroke after surgical revascularization for cerebral artery stenosis associated with childhood-onset moyamoya syndrome. We deem that decrease of blood pressure by endovascular revascularization and improvement of cerebral perfusion by surgical revascularization may have jeopardized the cerebral deep watershed zone to cerebral ischemia followed by cerebral hyperperfusion syndrome and caused transient ischemic attack and cerebrovascular stroke in our patient. Revascularization could be a double-edge sword for c-TA patients presenting with concomitant renal artery stenosis and cerebral artery stenosis, and should be performed with caution. Quantitative analysis of cerebral blood flow by brain magnetic resonance imaging and angiography should be performed within 48 hours after surgical revascularization in c-TA.
Adolescent*
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Angiography
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Blood Pressure
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Brain
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Brain Ischemia
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Cerebral Arteries*
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Cerebrovascular Circulation
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Constriction, Pathologic*
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Female*
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Humans
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Hypertension, Renovascular
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Ischemic Attack, Transient
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Magnetic Resonance Imaging
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Moyamoya Disease*
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Perfusion
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Renal Artery Obstruction
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Stroke
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Takayasu Arteritis*
5.Hepatitis B Screening and Vaccination Practices in Asian American Primary Care.
Danny CHU ; Ju Dong YANG ; Anna S LOK ; Tram TRAN ; Eduardo Bruno MARTINS ; Elizabeth FAGAN ; Franck ROUSSEAU ; W Ray KIM
Gut and Liver 2013;7(4):450-457
BACKGROUND/AIMS: Screening for hepatitis B virus (HBV) is recommended in populations with anticipated prevalence > or =2%. This study surveyed HBV screening and vaccination practices of Asian American primary care providers (PCPs). METHODS: Approximately 15,000 PCPs with Asian surnames in the New York, Los Angeles, San Francisco, Houston, and Chicago areas were invited to participate in a web-based survey. Asian American PCPs with > or =25% Asian patients in their practice were eligible. RESULTS: Of 430 (2.9%) survey respondents, 217 completed the survey. Greater than 50% followed > or =200 Asian patients. Although 95% of PCPs claimed to have screened patients for HBV, 41% estimated that < or =25% of their adult Asian patients had ever been screened, and 50% did not routinely screen all Asian patients. In a multivariable analysis, the proportion of Asian patients in the practice, provider geographic origin and the number of liver cancers diagnosed in the preceding 12 months were significantly associated with a higher likelihood of screening for HBV. Over 80% of respondents reported that < or =50% of their adult Asian patients had received the HBV vaccine. CONCLUSIONS: Screening and vaccination for HBV in Asian American patients is inadequate. Measures to improve HBV knowledge and care by primary-care physicians are critically needed.
Adult
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Asian Americans
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Asian Continental Ancestry Group
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Chicago
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Data Collection
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Hepatitis
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Hepatitis B
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Hepatitis B virus
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Hepatitis B, Chronic
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Humans
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Liver Neoplasms
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Los Angeles
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Mass Screening
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New York
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Prevalence
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Primary Health Care
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San Francisco
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Vaccination
6.A Systematic Classification of the Congenital Bronchopulmonary Vascular Malformations: Dysmorphogeneses of the Primitive Foregut System and the Primitive Aortic Arch System.
Meng Luen LEE ; Hung Chi LUE ; Ing Sh CHIU ; Han Yao CHIU ; Lon Yen TSAO ; Ching Yuan CHENG ; Albert D YANG
Yonsei Medical Journal 2008;49(1):90-102
PURPOSE: We reviewed the cases of 33 patients from our clinic and 142 patients from the literature with congenital bronchopulmonary vascular malformations (BPVM), systematically analyzed the bronchopulmonary airways, pulmonary arterial supplies, and pulmonary venous drainages, and classified these patients by pulmonary malinosculation (PM). MATERIALS AND METHODS: From January 1990 to January 2007, a total of 33 patients (17 men or boys and 16 women or girls), aged 1 day to 24 years (median, 2.5 months), with congenital BPVM were included in this study. Profiles of clinical manifestations, chest radiographs, echocardiographs, esophagographs, computer tomography (CT), magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), cardiac catheterizations with angiography, contrast bronchographs, bronchoscopies, chromosomal studies, surgeries, and autopsies of these patients were analyzed to confirm the diagnosis of congenital BPVM. A total of 142 cases from the literature were also reviewed and classified similarly. RESULTS: The malformations of our 33 patients can be classified as type A isolated bronchial PM in 13 patients, type B isolated arterial PM in three, type C isolated venous PM in two, type D mixed bronchoarterial PM in five, type F mixed arteriovenous PM in one, and type G mixed bronchoarteriovenous PM in nine. CONCLUSION: Dysmorphogeneses of the primitive foregut system and the primitive aortic arch system may lead to haphazard malinosculations of the airways, arteries, and veins of the lung. A systematic classification of patients with congenital BPVM is clinically feasible by assessing the three basic bronchovascular systems of the lung independently.
Adolescent
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Adult
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Aorta, Thoracic/*abnormalities
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Child
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Child, Preschool
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Female
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Humans
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Infant
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Infant, Newborn
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Intestines/*abnormalities/*blood supply
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Lung/*abnormalities/*blood supply
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Male
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Vascular Malformations/*classification
7.High frequency electrical stimulation of sciatic nerve enhances skeletal muscle autophagy in mice.
Ying-Juan YANG ; Jeffrey E PESSIN ; Lan WANG
Acta Physiologica Sinica 2017;69(4):422-428
The aim of the present study was to investigate the effects of exercise on skeletal muscle autophagy. Trains of high-frequency electrical stimulation (pulses frequency: 100 Hz) were used to stimulate sciatic nerve and consequently induce muscle contraction of the left hindlimb. The unstimulated right hindlimb muscles were taken as control. The mice were sacrificed immediately (0), 30 or 60 min after the electrical stimulation by cervical dislocation, and gastrocnemius muscles were rapidly dissected and freeze-clamped in liquid nitrogen. AMP-activated protein kinase (AMPK) and the autophagy marker protein LC3 were detected by Western blotting, and muscle atrophy related genes including atrogin-1, MuRF-1, Bnip3, Bnip3l and CathepsinL were detected by using real-time qPCR. The results showed that, at 0 min after the electrical stimulation, the activity of AMPK and LC3-II/I ratio were significantly increased in left gastrocnemius muscles, compared with those of the muscles in the right hindlimb. The levels of atrogin-1, MuRF-1, Bnip3, Bnip3l and CathepsinL mRNA expressions were up-regulated by electrical stimulation. Meanwhile, the activity of autophagy related protein, ULK1 was significantly enhanced by electrical stimulation. These results suggest that electrical stimulation of sciatic nerve may induce the skeletal muscle autophagy, and this may be regulated through AMPK/ULK1-mediated signaling pathway.
8.Expression of integrin alpha5 and actin in the cells of intervertebral disc under cyclic hydrostatic pressure in vitro.
Sheng-ji YU ; Gui-xing QIU ; Yang BURTON ; Roth SANDRA ; Whyne CARI ; Yee ALBERT
Chinese Journal of Surgery 2005;43(24):1605-1608
OBJECTIVETo investigate the expression of integrin alpha5 and actin in the cells of intervertebral disc under cyclic hydrostatic pressure in vitro.
METHODSThe porcine lumbar intervertebral disc cells were isolated and cultured in vitro, and the cells underwent cyclic hydrostatic loading. After that, the expression of integrin alpha5 and actin in intervertebral disc cells were studied by means of morphology observing, Western blot and immunohistochemistry staining.
RESULTSThe morphology of intervertebral disc cells were changed into smaller and flatten shape, and the expression of integrin alpha5 and actin were decreased after loading.
CONCLUSIONSThe expression of integrin alpha5 decreases under cyclic hydrostatic pressure, and the actin is affected at the same time when signals are transferred into the cells by integrin alpha5. That may be one of the important mechanisms of the mechanotransduction in the cells of intervertebral disc.
Actins ; metabolism ; Animals ; Cells, Cultured ; Hydrostatic Pressure ; adverse effects ; Integrin alpha5 ; metabolism ; Intervertebral Disc ; cytology ; Mechanotransduction, Cellular ; Swine
9.Genetic polymorphisms in NAT1, NAT2, GSTM1, GSTP1 and GSTT1 and susceptibility to colorectal cancer among Filipinos
Eva Maria C. Cutiongco-de la Paz ; Corazon A. Ngelangel ; Virgilio P. Bañ ; ez ; Francisco T. Roxas ; Catherine Lynn T. Silao ; Jose B. Nevado Jr. ; Alberto B. Roxas ; Oliver G. , Florendo ; Ma. Cecilia M. Sison ; Orlino Bisquera, Jr ; Luminardo M. Ramos ; Elizabeth A. Nuqui ; Arnold Joseph M. Fernandez ; Maria Constancia O. Carrillo ; Beatriz J. Tiangco ; Aileen D. Wang ; Rosalyn H. Sebastian ; Richmond B. Ceniza ; Leander Linus Philip P. Simpao ; Lakan U. Beratio ; Eleanor A. Dominguez ; Albert B. Albay Jr. ; Alfredo Y. Pontejos Jr. ; Nathaniel W. Yang ; Arsenio A. Cabungcal ; Rey A. Desales ; Nelia S. Tan-Liu ; Sullian S. Naval ; Roberto M. Montevirge ; Catalina de Siena E. Gonda-Dimayacyac ; Pedrito Y. Tagayuna ; John A. Coloma ; Gil M. Vicente ; Higinio T. Mappala ; Alex C. Tapia ; Emmanuel F. Montana Jr. ; Jonathan M. Asprer ; Reynaldo O. Joson ; Sergio P. Paguio ; Tristan T. Chipongian ; Joselito F. David ; Florentino C. Doble ; Maria Noemi G. Pato ; Benito B. Bionat Jr ; Hans Francis D. Ferraris ; Adonis A. Guancia ; Eriberto R. Layda ; Andrew D. Dimacali ; Conrado C. Cajucom ; Richard C. Tia ; Mark U. Javelosa ; Regie Lyn P. Santos-Cortez ; Frances Maureen C. Rocamora ; Roemel Jeusep Bueno ; Carmencita D. Padilla
Acta Medica Philippina 2017;51(3):216-222
Objectives. Polymorphisms in metabolic genes which alter rates of bioactivation and detoxification have been shown to modulate susceptibility to colorectal cancer. This study sought to evaluate the colorectal cancer risk from environmental factors and to do polymorphism studies on genes that code for Phase I and II xenobiotic metabolic enzymes among Filipino colorectal cancer patients and matched controls. Methods. A total of 224 colorectal cancer cases and 276 controls from the Filipino population were genotyped for selected polymorphisms in GSTM1, GSTP1, GSTT1, NAT1 and NAT2. Medical and diet histories, occupational exposure and demographic data were also collected for all subject participants.Results. Univariate logistic regression of non-genetic factors identified exposure to UV (sunlight) (OR 1.99, 95% CI: 1.16-3.39) and wood dust (OR 2.66, 95% CI: 1.21-5.83) and moldy food exposure (OR 1.61, 95% CI:1.11-2.35) as risk factors; while the NAT2*6B allele (recessive model OR 1.51, 95% CI :1.06-2.16; dominant model OR 1.87, 95% CI: 1.05-3.33) and homozygous genotype (OR 2.19, 95% CI: 1.19-4.03) were found to be significant among the genetic factors. After multivariate logistic regression of both environmental and genetic factors, only UV radiation exposure (OR 2.08, 95% CI: 1.21-3.58) and wood dust exposure (OR 2.08, 95% CI: 0.95-5.30) remained to be significantly associated with increasing colorectal cancer risk in the study population.Conclusion. This study demonstrated that UV sunlight and wood dust exposure play a greater role in influencing colorectal cancer susceptibility than genotype status from genetic polymorphisms of the GST and the NAT` genes.
Colorectal Neoplasms
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Polymorphism, Genetic