1.The Immunological Study of Megakaryocytes
Mo YANG ; Karen LI ; Ki Wai CHIK ; Dong Chang ZHAO ; Miao YAN ; Chi Kong LI ; Matthew Ming Kong SHING ; Tai Fai FOK ; Patrick Man Pan YUEN
Journal of Experimental Hematology 2000;8(1):5-9
The immunological role of megakaryocytes is not well known. This project studies the involvement of megakaryocytes on immuno-inflammatory processes and the possible mechanism via the adhesion molecule CD36 and the synthesis of relevant cytokines. The expression of adhesion protein CD36 on human platelets, megakaryocytes and megakaryocytic cell lines (Meg-01, Dami, CHRF-288-11 and M-07e) was analyzed by using flow cytometry, ELISA and immunocytochemical methods. The expression of interleukin-1 (IL-1) to interleukin-10 (IL-10), TNF-alpha, TNF-gamma and IFN-gamma on the four megakaryocytic cell lines was also determined by RT-PCR. The effect of IL-1beta, IL-3, IL-6 and TPO on murine megakaryocyte colony formation (CFU-MK) was studied by using a plasma clot culture system. The CFU-MK was confirmed by acetylcholine esterase staining. The results showed that: (1) CD36 was expressed on platelets, megakaryocytes and the four megakaryocytic cell lines, the relative expression level is as follows: platelets > megakaryocytes > Meg-01 > Dami > CHRF-288-11 > M-07e, suggesting that the level of CD36 expression correlates with the degree of maturity of megakaryocytic differentiation; (2) inflammatory cytokines TNF-alpha, IL-1beta, IL-3 and IL-6 were detected in all the four megakaryocytic cell lines, suggesting that different stages of megakaryocytes can be as a source of inflammatory cytokines; and (3) IL-1beta, IL-3 and IL-6, as well as TPO, play a stimulating effect on CFU-MK formation, suggesting that there is an "autocrine" effect on megakaryocytopoiesis. The data obtained suggest that megakaryocytes may involve in immuno-inflammatory processes via the synthesis of platelet adhesion molecules and inflammatory cytokines.
2.Development of Korean Neurobehavioral Test Battery - Assessment of the Validity of Traditional and Computerized Neurobehavioral Tests.
Jong Hak CHUNG ; Chang Yoon KIM ; Joon Sa KONG ; Man Joong JEON ; Park Chin HONG
Korean Journal of Preventive Medicine 1998;31(4):692-707
Aim. A neurobehavioral test for workers exposed to organic solvents in the workplace can be affected by many factors : age, education, motivation, ethnicity, etc. To apply more suitable neurobehavioral test for Korean workers, we evaluated the validity of several items of computerized and traditional neurobehavioral tests. Methods. We have applied eleven tests : four items of computerized neurobehavioral test(Swedish Performance Evaluation System) including Addition, Symbol-Digit, Digit Span, and Finger tapping speed, and seven items of traditional neurobehavioral test consisting of Addition, Digit-Symbol , Digit Span, Benton visual retention test, Pursuit aiming, Pegboard, and Tapping. These tests were performed on 96 workers exposed to solvents, and 100 reference workers. The concurrent and construct validities were evaluated by group difference, correlation with age, educational level, hippuric acid level, neurotoxic symptom, current exposure level, multitrait-multimethod matrix, factor analysis, and discriminant analysis. Results. Statistically significant differences were observed between the workers exposed to solvents and referents in computerized Symbol-Digit, Finger tapping speed, traditional Digit-Symbol and Pegboard. The computerized Symbol-Digit, traditional Digit-Symbol, Addition, Benton visual retention test, and Pegboard were found to be related to the age. The performance of computerized Symbol-Digit, Addition, and traditional Digit-Symbol were found to be related to the educational level significantly. The computerized Symbol-Digit, Finger tapping speed, and traditional Digit-Symbol were found to be related to hippuric acid, and neurotoxic symptom. The discriminability of Finger tapping speed, and Pegboard was better than the other tests. In discriminant analysis, the model with two variables, the computerized Symbol-Digit and Pegboard, classified almost 70 percent of the workers correctly. Conclusions. These results suggest that the computerized Symbol-Digit, Finger tapping speed, and Pegboard are more satisfactory for our purpose, and the Addition, Tapping, Benton visual retention test, and Pursuit aiming are less valid than other items. These may allow the reasonable selection of core neurobehavioral tests for workers exposed to solvents in Korea.
Education
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Fingers
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Korea
;
Motivation
;
Solvents
3.Quality of root canal fillings using three gutta-percha obturation techniques.
Edith Siu Shan HO ; Jeffrey Wen Wei CHANG ; Gary Shun Pan CHEUNG
Restorative Dentistry & Endodontics 2016;41(1):22-28
OBJECTIVES: The goal of this study was to compare the density of gutta-percha root fillings obturated with the following techniques: cold lateral (CL) compaction, ultrasonic lateral (UL) compaction, and warm vertical (WV) compaction. MATERIALS AND METHODS: Thirty-three extracted mandibular first molars, with two separate mesial canals in each, were selected. After instrumentation, the canals were stratified into three groups based on canal length and curvature, and underwent obturation with one of the techniques. No sealer was used in order to avoid masking any voids. The teeth were imaged pre- and post-obturation using micro-computed tomography. The reconstructed three-dimensional images were analyzed volumetrically to determine the amount of gutta-percha present in every 2 mm segment of the canal. P values < 0.05 were considered to indicate statistical significance. RESULTS: The overall mean volume fraction of gutta-percha was 68.51 +/- 6.75% for CL, 86.56 +/- 5.00% for UL, and 88.91 +/- 5.16% for WV. Significant differences were found between CL and UL and between CL and WV (p < 0.05), but not between UL and WV (p = 0.526). The gutta-percha density of the roots treated with WV and UL increased towards the coronal aspect, but this trend was not noted in the CL group. CONCLUSIONS: WV compaction and UL compaction produced a significantly denser gutta-percha root filling than CL compaction. The density of gutta-percha was observed to increase towards the coronal aspect when the former two techniques were used.
Dental Pulp Cavity*
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Gutta-Percha*
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Imaging, Three-Dimensional
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Masks
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Molar
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Tooth
;
Ultrasonics
4.Quality of root canal fillings using three gutta-percha obturation techniques.
Edith Siu Shan HO ; Jeffrey Wen Wei CHANG ; Gary Shun Pan CHEUNG
Restorative Dentistry & Endodontics 2016;41(1):22-28
OBJECTIVES: The goal of this study was to compare the density of gutta-percha root fillings obturated with the following techniques: cold lateral (CL) compaction, ultrasonic lateral (UL) compaction, and warm vertical (WV) compaction. MATERIALS AND METHODS: Thirty-three extracted mandibular first molars, with two separate mesial canals in each, were selected. After instrumentation, the canals were stratified into three groups based on canal length and curvature, and underwent obturation with one of the techniques. No sealer was used in order to avoid masking any voids. The teeth were imaged pre- and post-obturation using micro-computed tomography. The reconstructed three-dimensional images were analyzed volumetrically to determine the amount of gutta-percha present in every 2 mm segment of the canal. P values < 0.05 were considered to indicate statistical significance. RESULTS: The overall mean volume fraction of gutta-percha was 68.51 +/- 6.75% for CL, 86.56 +/- 5.00% for UL, and 88.91 +/- 5.16% for WV. Significant differences were found between CL and UL and between CL and WV (p < 0.05), but not between UL and WV (p = 0.526). The gutta-percha density of the roots treated with WV and UL increased towards the coronal aspect, but this trend was not noted in the CL group. CONCLUSIONS: WV compaction and UL compaction produced a significantly denser gutta-percha root filling than CL compaction. The density of gutta-percha was observed to increase towards the coronal aspect when the former two techniques were used.
Dental Pulp Cavity*
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Gutta-Percha*
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Imaging, Three-Dimensional
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Masks
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Molar
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Tooth
;
Ultrasonics
5.Bicarbonate secretion by the female reproductive tract and its impact on sperm fertilizing capacity.
Chen-Xi ZHOU ; Xiao-Fei WANG ; Hsiao-Chang CHAN
Acta Physiologica Sinica 2005;57(2):115-124
The luminal fluid environment of the female reproductive tract is considered critical for the sperm to undergo a series of molecular events leading to the final acquisition of their fertilizing capacity. It has been shown that the fluid in the female reproductive tract contains high content of HCO3- and it plays an important role in sperm functions including sperm motility, capacitation, hyperactivation and acrosome reaction. This review summarizes the effects of HCO3- on sperm functions occurring in the female reproductive tract and discusses the transport mechanisms involved in mediating uterine HCO3- secretion. New evidence is also presented to show possible cause of female infertility due to defective HCO3- transporting mechanism.
Animals
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Bicarbonates
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metabolism
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Female
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Fertilization
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physiology
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Humans
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Male
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Sperm Capacitation
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physiology
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Sperm-Ovum Interactions
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physiology
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Uterus
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metabolism
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secretion
6.Acrosome reaction in the cumulus oophorus revisited: involvement of a novel sperm-released factor NYD-SP8.
Ting Ting SUN ; Chin Man CHUNG ; Hsiao Chang CHAN
Protein & Cell 2011;2(2):92-98
Fertilization is a process involving multiple steps that lead to the final fusion of one sperm and the oocyte to form the zygote. One of the steps, acrosome reaction (AR), is an exocytosis process, during which the outer acrosome membrane fuses with the inner sperm membrane, leading to the release of acrosome enzymes that facilitate sperm penetration of the egg investments. Though AR has been investigated for decades, the initial steps of AR in vivo, however, remain largely unknown. A well elucidated model holds the view that AR occurs on the surface of the zona pellucida (ZP), which is triggered by binding of sperm with one of the ZP glycosylated protein, ZP3. However, this model fails to explain the large number of 'falsely' acrosome-reacted sperms found within the cumulus layer in many species examined. With the emerging evidence of cross-talk between sperm and cumulus cells, the potential significance of AR in the cumulus oophorus, the outer layer of the egg, has been gradually revealed. Here we review the acrosome status within the cumulus layer, the cross-talk between sperm and cumulus cells with the involvement of a novel sperm-released factor, NYD-SP8, and re-evaluate the importance and physiological significance of the AR in the cumulus in fertilization.
Acrosome Reaction
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physiology
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Cell Communication
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Cumulus Cells
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metabolism
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Female
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Fertilization
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physiology
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Humans
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Male
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Membrane Proteins
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metabolism
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Oocytes
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metabolism
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Progesterone
;
physiology
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Spermatozoa
;
metabolism
7.Clinical Study of Primary Chest Wall Tumors.
Chang Gon KIM ; Ja Hong KUH ; Kong Soo KIM
The Korean Journal of Thoracic and Cardiovascular Surgery 1998;31(2):155-161
Between January 1979 and August 1996, resection of a primary chest wall tumor was done in 51 patients. The mean age of the patients was 36.1 years (2 to 69 years). A palpable mass was the most common symptom (32 patients, 62.7%). The tumor was malignant in 11 patients (21.6%) and benign in 40 patients (78.4%). The tumors in 32 patients (62.7%) had developed from the bony or the cartilaginous wall and in 19 patients (37.3%) from soft tissue. Thirty seven of the patients with benign tumors were treated by excision (three of the patients: wide resection and reconstruction) without recurrence or death, and they are currently free from disease. Most malignancies (8 patients) were treated by wide resection and chest wall reconstruction. Five of them are currently alive. The chest wall reconstruction with Marlex mesh, Prolene mesh, or Teflon felt was done in five of the patients with malignant tumors.
Humans
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Polypropylenes
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Polytetrafluoroethylene
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Recurrence
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Thoracic Wall*
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Thorax*
8.Chondrosarcoma Arising from Benign Bone Tumor due to Malignant Transformation.
Wan hyeong CHO ; Won Seok SONG ; Chang Bae KONG ; Yun Suk HONG ; Jung Dong LEE ; Dae Geun JEON
The Journal of the Korean Bone and Joint Tumor Society 2011;17(1):17-22
PURPOSE: We analyzed the oncological outcome and prognostic factor of the chondrosarcoma arising from benign bone tumor due to malignant transformation. MATERIALS AND METHODS: From April 1986 to April 2009, 18 cases were considered eligible. We analyzed retrospectively the patient's characteristics and prognostic factors that affect to the local recurrence and distant metastasis. RESULTS: As classified by primary benign bone tumor, 4 cases were solitary osteochondroma, 11 cases were multiple osteochondromatosis and 3 cases were multiple enchondromatosis. The mean follow-up period was 85 months. The 5-year disease free survival rate of 18 patients was 85.9%. Their overall MSTS score was 25.2 (84%). There were local recurrence in 3 cases and no distant metastasis. We found that tumor location and surgical margin affected to the prognosis significantly. CONCLUSION: In secondary chondrosarcoma patients, the prognosis was good relatively and tumor location and surgical margin are important prognosis factor.
Chondrosarcoma
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Disease-Free Survival
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Enchondromatosis
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Follow-Up Studies
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Humans
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Neoplasm Metastasis
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Osteochondroma
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Osteochondromatosis
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Prognosis
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Recurrence
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Retrospective Studies
9.Red yeast rice increases excretion of bile acids in hamsters.
Ka-Ying MA ; Ze-Sheng ZHANG ; Shu-Xin ZHAO ; Qi CHANG ; Yin-Mei WONG ; Sai Ying Venus YEUNG ; Yu HUANG ; Zhen-Yu CHEN
Biomedical and Environmental Sciences 2009;22(4):269-277
OBJECTIVETo investigate the hypocholesterolemic activity of red yeast rice (RYR) and its underlying mechanism.
METHODSThree groups of hamsters were fed either the control diet or one of the two experimental diets containing by weight 0.1% RYR (0.1RYR) or 0.3% RYR (0.3RYR). Blood (0.5 mL) was collected from the retro-orbital sinus into a heparinized capillary tube at the end of week 0, 3, and 6. Plasma lipoproteins were measured using enzymatic kits, while fecal neutral and acidic sterols were quantified using a gas-liquid chromatography.
RESULTSPlasma total cholesterol was reduced by 12% in 0.1RYR group and by 18% in 0.3RYR group compared with the control value. Similarly, plasma triacylglycerol was decreased by 11% in 0.1RYR group and by 24% in 0.3RYR group. Western blotting analysis demonstrated that RYR had no effect on sterol regulatory element binding protein 2, liver X receptor, 3-hydroxy-3-methylglutary-CoA reductase, LDL receptor, and cholesterol-7alpha-hydroxylase. HPLC analysis confirmed that RYR contained 0.88% monacolin K. It was recently found that RYR supplementation increased excretion of fecal acidic sterols by 3-4 folds compared with the control value.
CONCLUSIONHypocholesterolemic activity of RYR is mediated at least partially by enhancement of acidic sterol excretion.
Animals ; Bile Acids and Salts ; secretion ; Biological Products ; pharmacology ; Blotting, Western ; Body Weight ; drug effects ; Cholesterol ; metabolism ; Cholesterol 7-alpha-Hydroxylase ; metabolism ; Cricetinae ; Dietary Supplements ; Feces ; chemistry ; Feeding Behavior ; drug effects ; Hydroxymethylglutaryl CoA Reductases ; metabolism ; Lipoproteins ; blood ; Liver ; enzymology ; Liver X Receptors ; Naphthalenes ; analysis ; Organ Size ; drug effects ; Orphan Nuclear Receptors ; metabolism ; Receptors, LDL ; metabolism ; Sterol Regulatory Element Binding Protein 2 ; metabolism ; Weight Gain ; drug effects
10.Epithelial ion channels in the regulation of female reproductive tract fluid microenvironment: implications in fertility and infertility.
Hsiao-Chang CHAN ; Qiong HE ; Louis-Chukwuemeka AJONUMA ; Xiao-Fei WANG
Acta Physiologica Sinica 2007;59(4):495-504
An optimal fluid microenvironment in the female reproductive tract is considered to be crucial for successful reproductive events. Fluid absorption and secretion across the reproductive tract epithelia largely depends on electrolyte transport through the apically and basolaterally located ion channels, working together with an array of other transporters. This review will discuss the role of epithelial sodium channel (ENaC) and the cystic fibrosis transmembrane conductance regulator (CFTR) in regulating the fluid volume and composition of the reproductive tract and their importance in various reproductive events such as sperm capacitation and implantation. Disturbance of the fluid microenvironment due to defects or abnormal regulation of these ion channels as causes for a number of pathological conditions, such as ovarian hyperstimulation syndromes, hydrosalpinx and infertility, is also discussed.
Animals
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Cystic Fibrosis Transmembrane Conductance Regulator
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physiology
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Epithelial Sodium Channels
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physiology
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Female
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Fertility
;
physiology
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Humans
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Infertility, Female
;
physiopathology