ABSTRACT
In the literature various causes of opacification of hydrophilic lenses have been described. Pronounced opacity is a complication that must be taken seriously because it can lead to explantation or exchange of the intraocular lens (IOL). The calcification of hydrophilic IOLs is often made responsible for an explantation. Despite the rapidly increasing number of intravitreal injections, they have so far not been associated with opacification of lenses. This article reports on a female patient where opacification of the hydrophilic lens was obviously associated with multiple intravitreal injections over several years. It involved a secondary calcification with calcium phosphate deposition directly under the surface of the IOL. Possible pathomechanisms are discussed. Due to the increasing number of intravitreal injections the association with IOL opacity should be further evaluated in the future. Generally, with hydrophilic lens materials it must be taken into consideration that these can become opaque following diverse interventions.
Subject(s)
Cataract , Lenses, Intraocular , Phacoemulsification , Bevacizumab , Device Removal , Female , Humans , Postoperative Complications , Prosthesis FailureABSTRACT
We assessed the 24-week efficacy and safety of teneligliptin, a novel dipeptidyl peptidase-4 inhibitor, in Korean patients with type 2 diabetes mellitus (T2DM) that was inadequately controlled with diet and exercise. The present study was designed as a multicentre, randomized, double-blind, placebo-controlled, parallel-group, phase III study. Patients (n = 142) were randomized 2 : 1 into two different treatment groups as follows: 99 received teneligliptin (20 mg) and 43 received placebo. The primary endpoint was change in glycated haemoglobin (HbA1c) level from baseline to week 24. Teneligliptin significantly reduced the HbA1c level from baseline compared with placebo after 24 weeks. At week 24, the differences between changes in HbA1c and fasting plasma glucose (FBG) in the teneligliptin and placebo groups were -0.94% [least-squares (LS) mean -1.22, -0.65] and -1.21 mmol/l (-1.72, -0.70), respectively (all p < 0.001). The incidence of hypoglycaemia and adverse events were not significantly different between the two groups. This phase III, randomized, placebo-controlled study provides evidence of the safety and efficacy of 24 weeks of treatment with teneligliptin as a monotherapy in Korean patients with T2DM.
Subject(s)
Diabetes Mellitus, Type 2/drug therapy , Dipeptidyl-Peptidase IV Inhibitors/therapeutic use , Hyperglycemia/prevention & control , Hypoglycemia/prevention & control , Insulin Resistance , Pyrazoles/therapeutic use , Thiazolidines/therapeutic use , Administration, Oral , Blood Glucose/analysis , Combined Modality Therapy/adverse effects , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/diet therapy , Diabetes Mellitus, Type 2/therapy , Diet, Diabetic , Dipeptidyl-Peptidase IV Inhibitors/administration & dosage , Dipeptidyl-Peptidase IV Inhibitors/adverse effects , Double-Blind Method , Exercise , Glycated Hemoglobin/analysis , Humans , Hyperglycemia/epidemiology , Hypoglycemia/chemically induced , Hypoglycemia/epidemiology , Incidence , Patient Compliance , Pyrazoles/administration & dosage , Pyrazoles/adverse effects , Republic of Korea/epidemiology , Thiazolidines/administration & dosage , Thiazolidines/adverse effects , Time FactorsABSTRACT
We measured heating of isotonic saline by three fluid warmers in six experiments: saline at 5 °C or 20 °C delivered at 30, 50 or 100 ml.min(-1) . At the three flow rates, the enFLOW(®) , buddy lite(™) and ThermoSens(®) systems heated 5 °C saline to mean (SD) temperatures of: 41.1 (0.5) °C, 37.7 (0.6) °C and 39.1 (0.6) °C; to 40.3 (0.8) °C, 33.9 (1.6) °C and 39.3 (0.7) °C; and to 37.1 (0.8) °C, 24.0 (1.3) °C and 37.6 (1.0) °C, respectively, p < 0.0001 for each experiment. The mean (SD) times taken to heat 5 °C saline were: 16.6 (1.7) s, 258.4 (58.9) s and 134.2 (79.6) s; 16.9 (1.8) s, 256.2 (62.2) s and 182.5 (74.5) s; and 21.5 (1.5) s, 275.9 (49.3) s and 313.5 (18.0) s, respectively, p < 0.0003 for each experiment. The results for saline at 20 °C were similar. The enFLOW system heated saline above 36 °C faster than the ThermoSens system, whereas the buddy lite often failed to achieve 36 °C.
Subject(s)
Rewarming/instrumentation , Analysis of Variance , Equipment Design , Hot Temperature , Rewarming/methods , Sodium Chloride , Time FactorsABSTRACT
System requirements for many military electro-optic and IR camera systems reflect the need for both wide-field-of-view situational awareness as well as high-resolution imaging for target identification. In this work we present a new imaging system architecture designed to perform both functions simultaneously and the AWARE 10 camera as an example at visible wavelengths. We first describe the basic system architecture and user interface followed by a laboratory characterization of the system optical performance. We then describe a field experiment in which the camera was used to identify several maritime targets at varying range. The experimental results indicate that users of the system are able to correctly identify ~10 m targets at between 4 and 6 km with 70% accuracy.
ABSTRACT
After heart transplantation (HT), transient right heart failure (RHF) is common. If it does not improve with appropriate medical therapy, we must consider mechanical support. Recently, extracorporeal membrane oxygenation (ECMO) has shown better results than a right ventricular assist device or retransplantation. Two HT patients with hypertrophic cardiomyopathy had cold ischemic times beyond >240 minutes. After HT, their right heart function worsened and was unresponsive to medical therapy. After our application of ECMO, weaning was successful and the patients were discharged without complication. Early application of ECMO for RHF after HT is a good option.
Subject(s)
Extracorporeal Membrane Oxygenation , Heart Failure/therapy , Heart Transplantation , Adult , Female , Heart Failure/physiopathology , Humans , Middle AgedABSTRACT
AIMS: The influence of hyperglycaemia on the performance of glomerular filtration rate (GFR) estimating equations remains to be determined. We compared the performance of creatinine-based GFR with cystatin C-based GFR in patients with Type 2 diabetes according to glycaemic status. METHODS: In a cross-sectional study of 210 patients with Type 2 diabetes, we staged glycaemic status by HbA(1c) tertiles [HbA(1c) ≤ 75 mmol/mol (9.0%) (n = 70), HbA(1c) 76-95 mmol/mol (9.1-10.8%) (n = 70), HbA(1c) >95 mmol/mol (10.8%) (n = 70)] and measured GFR. Isotopic GFR was measured using renal dynamic imaging with (99m) Tc-diethylene-triamine-penta-acetic acid. Estimated GFR (eGFR) was measured using creatinine-based formulae (Cockcroft-Gault-eGFR, the Modification of Diet in Renal Disease equation-eGFR and the Chronic Kidney Disease Epidemiology Collaboration formula-eGFR) and a cystatin C-based formula (cystatin C-eGFR). RESULTS: The isotopic GFR of all patients was 93.1 ± 34.1 ml min(-1) 1.73 m(-2). All methods for estimating GFR underestimated isotopic GFR [Cockcroft-Gault-eGFR (68.8 ± 38.6 ml min(-1) 1.73 m(-2) ) (P < 0.05), Modification of Diet in Renal Disease-eGFR (74.8 ± 31.3 ml min(-1) 1.73 m(-2) ) (P < 0.05), Chronic Kidney Disease Epidemiology Collaboration-eGFR (72.9 ± 26.6 ml min(-1) 1.73 m(-2)) (P < 0.05) and cystatin C-eGFR (83.5 ± 33.2 ml min(-1) 1.73 m(-2)) (P < 0.05)]. In all patient groups, cystatin C-eGFR was less biased and more accurate than the creatinine-based formulae, especially in the group with HbA(1c) > 95 mmol/mol (10.8%) where there was no difference between cystatin C-eGFR and isotopic GFR. CONCLUSIONS: Performance of cystatin C-eGFR was superior to creatinine-based GFR in patients with Type 2 diabetes with HbA(1c) >95 mmol/mol (10.8%).
Subject(s)
Blood Glucose/metabolism , Creatinine/blood , Cystatin C/blood , Diabetes Mellitus, Type 2/blood , Diabetic Nephropathies/blood , Glomerular Filtration Rate , Renal Insufficiency, Chronic/blood , Biomarkers/blood , Cross-Sectional Studies , Diabetic Nephropathies/physiopathology , Female , Humans , Hyperglycemia/blood , Male , Renal Insufficiency, Chronic/physiopathologyABSTRACT
AIMS: This study compared the efficacy and safety of tramadol/acetaminophen (T/A) and gabapentin in the management of painful diabetic neuropathy. METHODS: An open, randomized, comparative study was conducted. Subjects with painful symmetric neuropathy in the lower limbs and mean pain-intensity score > or = 4 on a numeric rating scale were eligible. Subjects were randomized to receive either tramadol (37.5 mg)/acetaminophen (325 mg) or gabapentin (300 mg) for 6 weeks. After 2 weeks of the titration period (1200 mg/day for gabapentin and three tablets/day for T/A), the doses were maintained if the pain was relieved. The primary efficacy outcome was a reduction in pain intensity. Secondary measures evaluated a pain relief scale, a Brief Pain Inventory, a 36-item Short Form Health Survey, average pain intensity and sleep disturbance. RESULTS: One hundred and sixty-three subjects (T/A 79; gabapentin 84) were included. At the final visit, the mean doses were 1575 mg/day for gabapentin and 4.22 tablets/day for T/A. Both groups were similar in terms of baseline pain intensity (mean intensity: T/A 6.7 +/- 1.6; gabapentin 6.3 +/- 1.6, P = 0.168). At the final visit, the mean reductions in pain intensity were similar in both groups (T/A -3.1 +/- 2.0; gabapentin -2.7 +/- 2.1, P = 0.744). Both groups had similar improvements in every Short Form Health Survey category and Brief Pain Inventory subcategory, and in the mean pain relief scores. CONCLUSION: This study suggests that the T/A combination treatment is as effective as gabapentin in the treatment of painful diabetic neuropathy in patients with Type 2 diabetes.
Subject(s)
Acetaminophen/administration & dosage , Amines/administration & dosage , Analgesics, Opioid/administration & dosage , Cyclohexanecarboxylic Acids/administration & dosage , Diabetes Mellitus, Type 2/drug therapy , Diabetic Neuropathies/drug therapy , Tramadol/administration & dosage , gamma-Aminobutyric Acid/administration & dosage , Adult , Aged , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/physiopathology , Diabetic Neuropathies/physiopathology , Double-Blind Method , Drug Therapy, Combination , Female , Gabapentin , Humans , Male , Middle Aged , Pain/drug therapy , Treatment OutcomeABSTRACT
Evaluating increasing circulating adiponectin levels is becoming an important strategy in the prevention of diabetes mellitus and cardiovascular events. This study was designed to investigate the effect of the angiotensin II receptor blocker valsartan on blood adiponectin levels and insulin sensitivity in patients with type 2 diabetes and mild-to-moderate hypertension. A total of 91 Korean patients were treated with 80 mg/day valsartan for 4 weeks followed by 160 mg/day for a further 8 weeks. Blood pressure, adiponectin levels and metabolic parameters were measured before and after treatment. The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated as an insulin sensitivity index. Valsartan significantly decreased mean blood pressure and increased circulating adiponectin levels. There were no differences in metabolic parameters, including HOMA-IR, glycosylated haemoglobin and lipid levels before and after treatment. These results indicated that valsartan increases circulating adiponectin levels, but does not change insulin sensitivity in patients with type 2 diabetes and mild-to-moderate hypertension.
Subject(s)
Adiponectin/blood , Angiotensin II Type 1 Receptor Blockers/pharmacology , Diabetes Mellitus, Type 2/drug therapy , Hypertension/drug therapy , Insulin Resistance , Tetrazoles/pharmacology , Valine/analogs & derivatives , Blood Glucose/metabolism , Body Mass Index , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/physiopathology , Female , Follow-Up Studies , Homeostasis , Humans , Hypertension/blood , Hypertension/physiopathology , Male , Middle Aged , Treatment Outcome , Valine/pharmacology , ValsartanABSTRACT
To estimate true Brix and alcoholic strength of must and wines without distillation, a novel approach using a refractometer and a hydrometer was developed. Initial Brix (I.B.), apparent refractometer Brix (A.R.), and apparent hydrometer Brix (A.H.) of must were measured by refractometer and hydrometer, respectively. Alcohol content (A) was determined with a hydrometer after distillation and true Brix (T.B.) was measured in distilled wines using a refractometer. Strong proportional correlations among A.R., A.H., T.B., and A in sugar solutions containing varying alcohol concentrations were observed in preliminary experiments. Similar proportional relationships among the parameters were also observed in must, which is a far more complex system than the sugar solution. To estimate T.B. and A of must during alcoholic fermentation, a total of 6 planar equations were empirically derived from the relationships among the experimental parameters. The empirical equations were then tested to estimate T.B. and A in 17 wine products, and resulted in good estimations of both quality factors. This novel approach was rapid, easy, and practical for use in routine analyses or for monitoring quality of must during fermentation and final wine products in a winery and/or laboratory.
Subject(s)
Alcohols/analysis , Carbohydrates/analysis , Refractometry/methods , Wine/analysis , China , Fermentation/physiology , Food Handling , Korea , Saccharomyces cerevisiae/metabolism , VitisABSTRACT
This study was designed to investigate the relationship between adipokines in metabolic syndrome and insulin resistance. Sixty male and female subjects with or without metabolic syndrome and type 2 diabetes were included. The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Compared with lean control subjects, patients with metabolic syndrome and type 2 diabetes had lower circulating levels of total adiponectin and high molecular weight (HMW) adiponectin, and higher levels of leptin and interleukin-6 (IL-6). Total and HMW adiponectin and the adiponectin/leptin (A/L) ratio were negatively correlated with HOMA-IR. After adjusting for age and sex, leptin, IL-6 and tumour necrosis factor-alpha (TNF-alpha) were positively correlated with HOMA-IR. After also adjusting for body mass index, HOMA-IR was found to be independently associated with leptin, A/L ratio and TNF-alpha levels. In conclusion, decreased total adiponectin and HMW adiponectin and increased leptin and IL-6 levels are characteristic of patients with metabolic syndrome and type 2 diabetes.
Subject(s)
Adipokines/blood , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Insulin Resistance , Metabolic Syndrome/blood , Metabolic Syndrome/complications , Adiponectin/blood , Adult , Aged , Case-Control Studies , Female , Homeostasis , Humans , Leptin/blood , Male , Middle Aged , Molecular Weight , Risk Factors , Statistics, NonparametricSubject(s)
Arteriovenous Malformations/surgery , Endoscopy, Gastrointestinal/methods , Gastric Mucosa/blood supply , Gastrointestinal Hemorrhage/surgery , Hemostasis, Endoscopic/methods , Arteriovenous Malformations/complications , Gastrointestinal Hemorrhage/etiology , Humans , Ligation/instrumentation , Risk Factors , Treatment OutcomeABSTRACT
The effects of ultraviolet (UV) intensity and wavelength on triclosan (TCS) photodegradation kinetic, efficiency, mechanisms and pathway were studied. The TCS photodegradation followed the pseudo-first order kinetic model at all UV intensities examined at the wavelengths of 254 and 365 nm and the photodegradation rate increased with increasing UV intensity. TCS photodegradation efficiencies of 90 to 98% and 79 to 90% were obtained at the wavelengths of 254 and 365 nm, respectively. TCS was degraded mainly by photon induced hydroxyl radicals while the direct photon reaction with TCS played a subordinate role. Chlorophenol, dichlorophenol and phenol were the intermediates detected in all experiments conducted. Dibenzodichloro-p-dioxin and dibenzo-p-dioxin were observed as the intermediates only at lower UV intensities investigated at the wavelength of 365 nm. Based on these intermediates, a complete TCS photolysis pathway was proposed for the first time.
Subject(s)
Triclosan/chemistry , Triclosan/radiation effects , Ultraviolet Rays , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/radiation effects , Hydroxyl Radical/chemistry , Hydroxyl Radical/metabolism , Photolysis , Photons , Time Factors , Triclosan/metabolism , Water Pollutants, Chemical/metabolismABSTRACT
This study was undertaken to examine the photocatalytic degradation of explosives hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) with a circular photocatalytic reactor, using a UV lamp as a light source and TiO2 as a photocatalyst. The effects of various parameters, such as the RDX or HMX concentration, the amount of TiO, and the initial pH, on the photocatalytic degradation rates of explosives were examined. In the presence of both UV light and TiO2 RDX and HMX were more effectively degraded than with either UV or TiO2 alone. The degradation rates were found to obey pseudo-first-order kinetics represented by the Langmuir-Hinshelwood model. Increases in the RDX and HMX degradation rates were obtained with decreasing initial concentrations of the explosives. The RDX and HMX degradation rates were higher at pH 7 than at either pH 3 or pH 11. A dose of approximately 0.7 g l(-1) of TiO2 degraded HMX more rapidly than did higher or lower TiO2 doses. RDX (20 mg l(-1)) photocatalysis resulted in an approximately 20% decrease in TOC, and HMX (5 mg l(-1)) photocatalysis resulted in a 60%, decrease in TOC within 150 minutes. A trace amount of formate was produced as an intermediate that was further mineralized by RDX or HMX photocatalysis. The nitrogen byproducts from the photocatalysis of RDX and HMX were mainly NO3- with NO2-, and NH4+. The total nitrogen recovery was about 60% from RDX (20 mg l(-1)), and 70% from HMX (5 mg l(-1)), respectively. Finally, a mechanism for RDX/HMX photocatalysis was proposed, along with supporting qualitative and quantitative evidence.
Subject(s)
Azocines/chemistry , Azocines/radiation effects , Heterocyclic Compounds, 1-Ring/chemistry , Heterocyclic Compounds, 1-Ring/radiation effects , Titanium/chemistry , Triazines/chemistry , Triazines/radiation effects , Ultraviolet Rays , Carbon/analysis , Catalysis , Formates/analysis , Hydrogen-Ion Concentration , Kinetics , Nitrogen/analysis , PhotochemistryABSTRACT
BACKGROUND: In sudden cardiac arrest, the effective maintenance of coronary artery blood flow is of paramount importance for myocardial preservation as well as cardiac recovery and patient survival. The purpose of this study was to directly compare the effects of pulsatile versus non-pulsatile circulation to coronary artery flow and myocardial preservation in a cardiac arrest condition. METHODS: A cardiopulmonary bypass circuit was constructed in a ventricular fibrillation model using fourteen Yorkshire swine weighing 25-35 kg each. The animals were randomly assigned to group I (n=7, non-pulsatile centrifugal pump) or group II (n=7, pulsatile T-PLS pump). Extracorporeal circulation was maintained for two hours at a pump flow of 2 L/min. The left anterior descending coronary artery flow was measured with an ultrasonic coronary artery flow measurement system at baseline (before bypass) and at every 20 minutes after bypass. Serologic parameters were collected simultaneously at baseline, 1 hour, and 2 hours after bypass in the systemic arterial and coronary sinus venous blood. The Mann-Whitney U test of STATISTICA 6.0 was used to determine intergroup significances using a p value of <0.05. RESULTS: The resistance index of the coronary artery was lower in group II and the difference was significant at 40 min, 80 min, 100 min and 120 min (p<0.05). The mean velocity of the coronary artery was higher in group II throughout the study, and the difference was significant from 20 min after starting the pump (p<0.05). The coronary artery blood flow was higher in group II throughout the study, and the difference was significant from 40 min to 120 min (p<0.05) except at 80 min. Serologic parameters showed no differences between the groups at 1 hour and 2 hours after bypass in the systemic and coronary sinus blood (p=NS). CONCLUSION: In the cardiac arrest condition, pulsatile extracorporeal circulation provides more blood flow, higher flow velocity and less resistance to coronary artery than non-pulsatile circulation.
Subject(s)
Coronary Circulation , Extracorporeal Circulation/methods , Heart Arrest, Induced , Pulsatile Flow , Animals , Blood Flow Velocity , Models, Animal , Swine , Ultrasonics , Ventricular FibrillationABSTRACT
The Moving Actuator type artificial heart(AnyHeart) as well as many other artificial hearts uses a motor as its power source. For controllability of control parameters such as pump rate, pump output, blood pressure profile and flow form, the precise motor speed control is important. However, because the implantable device has limited carrying capacity of hardware components in size and number, applying diverse motor control methods are not possible. In addition, the existing PI (Proportional-Integral) motor controller does not show satisfactory performance. A new controller that is sufficiently robust for the changes of load and physical system parameters has been designed and tested. The robust speed controller is based on the sliding mode control method that is applicable to a system of which the ranges of uncertainty in physical parameters are known. In a mock circulation system test, the actual speed showed good tracking characteristics in respect to the reference speed. Fast follow-up characteristics were also observed under high afterload and speed conditions. The speed error, current and power consumption were reduced by about 40%. The proposed control technique overcomes the limitations of the PI controller, and makes important improvements in both performance and stability.
Subject(s)
Electric Power Supplies , Heart Rate , Heart, Artificial , Algorithms , Blood Pressure , Cardiac Output , Friction , Humans , Models, Cardiovascular , Prosthesis Design , TorqueABSTRACT
OBJECTIVES: This study was performed to investigate the effect of dexamethasone on the expansion and transdifferentiation of transplanted neonatal pancreas cell clusters (NPCCs) in vivo. METHODS: Porcine NPCCs were generated from 1 to 3-day-old neonatal pigs. After transplantation (Tx) of 4000 islet equivalents (IEqs) of NPCCs beneath the renal subcapsular space of normoglycemic nude mice, dexamethasone (Dx, 1 mg/kg) or vehicles were injected daily. Intraperitoneal glucose tolerance testing (ip-GTT) was performed at 4 weeks (n = 4) and 10 weeks (n = 7) after Tx. After harvesting the grafts, total graft and beta-cell graft mass were determined by morphometric analysis. RESULTS: Although the mean value of AUCg was elevated in the Dx-treated group at 10 weeks after Tx, the glucose levels of all the animals by ip-GTT were within the normal range. At 10 weeks after Tx, the relative volume, absolute mass of beta-cells in the graft, and total graft mass were significantly lower in the Dx-treated group (relative volume of beta-cells: 22.0% versus 35.3%, P < 0.05; beta-cells mass: 1.0 +/- 1.2 mg versus 2.2 +/- 5.6 mg, P < 0.05, total graft mass: 4.4 +/- 5.4 mg versus 6.3 +/- 1.3 mg, P < 0.05, Dx-treated versus control), but there was no difference at 4 weeks. Morphologically prominent cystic structures were observed in the Dx group at 10 weeks. CONCLUSION: Our results suggest that dexamethasone suppresses the expansion and transdifferentiation of transplanted porcine NPCCs into beta-cells in normal nude mice.
Subject(s)
Cell Differentiation/drug effects , Dexamethasone/pharmacology , Islets of Langerhans Transplantation/physiology , Transplantation, Heterologous/physiology , Animals , Animals, Newborn , Cell Division/drug effects , Glucose Tolerance Test , Insulin/metabolism , Insulin Secretion , Mice , Mice, Nude , Subrenal Capsule Assay , SwineABSTRACT
A multifunctional, Korean-made artificial heart (AnyHeart) was developed, and prior to its clinical application, a cadaver-fitting study was performed. The study proposed to determine the optimal cannulation approach, implantation technique and route of the cannula to minimize the organ compression of AnyHeart. The anatomical feasibility and a variety of surgical techniques were evaluated using ten preserved, human cadavers. Implanting AnyHeart with ease is possible using various approaches, including a median sternotomy, and a right or left lateral thoracotomy. The lateral thoracotomy approach is shown to be safe and reproducible, especially in patients who have already undergone an operation that used a median sternotomy. The results of this study will guide improvements in the designs of cannulae and AnyHeart for future clinical applications.
Subject(s)
Heart, Artificial , Prosthesis Implantation/methods , Adolescent , Adult , Aged , Cadaver , Feasibility Studies , Female , Humans , Male , Middle Aged , Prosthesis Design , Prosthesis Fitting/methods , ThoracotomyABSTRACT
OBJECTIVES: The expression of the intermediate filament (IF) vimentin, usually considered a marker of mesenchymal cells, has been observed in the epithelial cells during embryogenesis, carcinogenesis, and dedifferentiation, suggesting that it might be useful as a marker of proliferating precursor cells in the pancreas. METHODS: Rat pancreata at E18 and at different time points after partial pancreatectomy (Px) and human and neonatal pig pancreatic tissue sections and monolayer cultured pancreatic duct cells were observed. All tissues were simultaneously immunostained with pancytokeratin and vimentin antibodies. In costained duct cells, PDX-1 or PCNA expression was also analyzed using confocal microscope images. RESULTS: In the rat embryonic pancreas at E18, all epithelial cells that formed ductlike structures expressed both cytokeratin and vimentin IF, whereas no duct cells costained for IF in the adult rat or neonatal pig pancreas. Such costaining reappeared in the following order: common pancreatic duct, main ducts, foci of regeneration and then disappeared completely at 30 days after Px. In humans, costaining was found in only 1 diabetic patient's pancreatic section, which was accompanied by massive duct cell proliferation. In monolayer culture, most of the duct cells of human and neonatal pigs coexpressed both IF proteins. Only a few costained duct cells also expressed PDX-1, and most of those cells were also stained with PCNA in rat embryonic pancreas and regenerating foci after partial Px. CONCLUSIONS: Vimentin IF expression might be a useful marker for pancreatic precursor cells and could be used to investigate the concept of the dedifferentiation of fully matured duct cells during the process of the beta-cell neogenesis.
Subject(s)
Pancreas/cytology , Pancreatic Ducts/cytology , Stem Cells/metabolism , Vimentin/metabolism , Animals , Biomarkers/metabolism , Cell Proliferation , Cells, Cultured , Humans , Pancreas/embryology , Pancreas/growth & development , Pancreatectomy , Pancreatic Ducts/growth & development , Pancreatic Ducts/metabolism , Rats , Stem Cells/cytology , SwineABSTRACT
The mechanical circulatory support system using moving-actuator mechanisms were developed by Seoul National University and Korea University. AnyHeart is a fully implanted pulsatile bi-ventricular assist device, and T-PLS is a pulsatile flow versatile extracorporeal life support system. Through lots of in-vitro and in-vivo experiments, the developed mechanical systems are faced to produce on commercial scale. This paper describes the recent progress of two mechanical circulatory support systems, AnyHeart and T-PLS.