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Myanmar has experienced considerable economic and social changes since its political transition in the early 2010s. Its agriculture sector has demonstrated rapid intensification and modernization. Agricultural best management practices (BMPs), e.g., drum seeders and laser land levelling, were introduced to rice farmers in Bago Region in 2012 to increase sustainable production and counter negative environmental impacts. The objective of this study was to determine the socioeconomic and agronomic changes due to the adoption of BMPs between adopters and non-adopters. Using a digital survey questionnaire application to collect household data, 200 farmers in eight villages were interviewed in 2012 and 2017. Data were analysed using uni- and multivariate statistics. Mediation analysis was utilized to evaluate the effect of the farmer group on rice yields. Overall, all farmers in this study experienced substantial positive changes over the course of five years in line with the national development efforts. Differences among adopters and non-adopters were not significant, but notable distinctions existed between cropping patterns. Rice-pulse farmers had higher yields ( + 0.4 t/ha), yet rice-rice farmers had larger cultivation areas, received higher agricultural credits, and had superior income levels. Nevertheless, rice yields remained low (

Dental pulp regeneration exploits tissue engineering concepts using stem cells/scaffolds/growth-factors. Extracted collagen is commonly used as a biomaterial-scaffold due to its biocompatibility/biodegradability and mimics the natural extracellular matrix. Adding biomolecules into a collagen-scaffold enhanced pulp regeneration. Acemannan, β-(1-4)-acetylated-polymannose, is a polysaccharide extracted from aloe vera. Acemannan is a regenerative biomaterial. Therefore, acemannan could be a biomolecule in a collagen-scaffold. Here, acemannan and native collagen were obtained and characterized. The AceCol-scaffold's physical properties were investigated using FTIR, SEM, contact angle, swelling, pore size, porosity, compressive modulus, and degradation assays. The AceCol-scaffold's biocompatibility, growth factor secretion, osteogenic protein expression, and calcification were evaluated in vitro. The AceCol-scaffolds demonstrated higher hydrophilicity, swelling, porosity, and larger pore size than the collagen scaffolds (p 0.05). Better cell-cell and cell-scaffold adhesion, and dentin extracellular matrix protein (BSP/OPN/DSPP) expression were observed in the AceCol-scaffold, however, DSPP expression was not detected in the collagen group. Significantly increased cellular proliferation, VEGF and BMP2 expression, and mineralization were detected in the AceCol-scaffold compared with the collagen-scaffold (p 0.05). Computer simulation revealed that acemannan's 3D structure changes to bind with collagen. In conclusion, the AceCol-scaffold synergistically provides better physical and biological properties than collagen. The AceCol-scaffold is a promising material for tissue regeneration.

The process of grouping a set of physical objects into classes of similar objects is called clustering. Clustering is a process of grouping the data into classes or cluster so that objects within a cluster have high similarity in comparison to one another, but are very dissimilar to objects in other clusters. Dissimilarities are assessed based on the attribute values describing the objects. This system studies how to compute dissimilarities between objects represented by interval scaled variables. This system is intended to implement the dissimilarity matrix for interval-scaled variables using Euclidean, Manhattan, and Minkowski distance methods. This stores a collection of proximities that are available for all pairs of n objects.

This Student registration at University involved students being registered in Student Affairs Department and make a deposit in Finance Department within the University, where they would present a form which had previously been filled in by the student. Students often wait for minutes, hours, half day or days to receive registration service for which they were waiting. Delays in the registration may result in difficulties of scheduling at speciality units and decrease in student satisfaction. This system examines the wide-spread problem of extended waiting times for registration. This system implements as student flow scheduling system and can help staff of student affairs department to reduce student congestion in department. This system uses Queuing analysis and Computer Simulation in Operation Research (OR) field. OR is a scientific approach to analyse problem and reduce waiting time. Simulation is the use of a system model that has the mapped characteristics of existence in order to produce the essence of actual operation. This system presents stand-alone application to help student registration using queuing analysis and computer simulation whose are finding appropriate waiting time for student affairs department.

Myanmar falls within the center of the genetic diversity of many economically important crops, including wild and cultivated rice (Oryza sativa L.). However, the majority of the genetic resources o...

Myanmar is well known as a primary center of plant genetic resources for rice. A considerable number of genetic diversity studies have been conducted in Myanmar using various DNA markers. However, this is the first report using DArTseq technology for exploring the genetic diversity of Myanmar rice. In our study, two ultra-high-throughput diversity array technology markers were employed to investigate the genetic diversity and population structure of local rice varieties in the Ayeyarwady delta, the major region of rice cultivation. The study was performed using 117 rice genotypes with 7643 SNP and 4064 silicoDArT markers derived from the DArT platform. Genetic variance among the genotypes ranged from 0 to 0.753 in SNPs, and from 0.001 to 0.954 in silicoDArT. Two distinct population groups were identified from SNP data analysis. Cluster analysis with both markers clearly separated traditional Pawsan varieties and modern high-yielding varieties. A significant divergence was found between populations according to the Fst values (0.737) obtained from the analysis of molecular variance, which revealed 74% genetic variation at the population level. These findings support rice researchers in identifying useful DNA polymorphisms in genes and pinpointing specific genes conferring desirable phenotypic traits for further genome-wide association studies and parental selection for recombination breeding to enhance rice varietal development and release.

The search for an inexpensive and effective way to improve the thermoelectric properties of organic materials could greatly expand the practical applications of a thermoelectric thin film generator. Here, we adopt a triple treatment of ethylene glycol ((CH2OH)2), ethanol (C2H5OH) doping and (CH2OH)2 dedoping to tune the micro stacking structure of PEDOT:PSS. The obtained PEDOT:PSS thermoelectric film material has a highest power factor (PF) of up to 330.597 μW m−1, which stems from the high Seebeck coefficient (S) and conductivity (σ). Furthermore, we fabricated a thermoelectric generator to explore the photothermal conversion process of the solar energy. The maximum power output of the home-made module device with solar energy as the heat source reached 9.8 nW. This work is a prospective experiment for the development of solar photothermal conversion based on such a thin film and device.

The exfoliation of graphite is an intriguing approach for simple, fast and large-scale production of graphene. In the present study, three types of electrolytes were investigated, namely an ionic liquid (H2SO4), aqueous acid (H3PO4) and inorganic salt ((NH4)2SO4). Different sonication times (15, 30, 45 and 60 min) at room temperature were used to assist the electrochemical exfoliation. The graphene that was produced was characterized by the zeta potential, surface electrical conductivity, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, field emission microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy (XPS). From the XRD analysis, it was observed that the graphene flakes had a broad peak centred at 26.5°, which corresponds to the (0 0 2) plane of graphene crystal. The FTIR spectrum revealed that the prominent peak was in conjunction with exfoliated graphene. The characteristic Raman bands were observed for the D, G and 2D bands and the ratio of I2D/IG was 1.7, which indicated that the exfoliated graphene was a multilayer structure. From the results, it was found that graphene obtained with the H2SO4 electrolyte that used a 45 min sonication time had the highest stability, best electrical conductivity, lowest crystallite size, fewer defects and lowest interlayer distance.

In this paper, the effect of Crystal structures on the carbon dioxide (CO2) adsorption capacities of difference calcium oxide (CaO) based adsorbents was investigated.

Introduction: Angiotensin-converting enzyme (ACE) inhibitors are commonly prescribed Anti-hypertensives which are first line treatments in patients with Diabetes. We report a rare but significant side-effect of ACE inhibitor treatment, relevant to Diabetic and non-diabetic patients alike. Case Details: We report the case of a 79 year male, with a background of Hypertension (HTN), established on Ramipril and Bendroflumethiazide, who was admitted following an episode of unresponsiveness secondary to Hypoglycaemia, which was initially presumed secondary to Alcohol, the intake of which was minimal. He did not have a history of Diabetes Mellitus. 7 weeks later, he had a similar presentation and as found to be profoundly Hypoglycaemic. On arrival, his observations were unremarkable except for CBG 1.9 and GCS of 14/15, which responded well to IM glucagon, and IV Dextrose. Relevant investigations revealed significantly impaired renal functions and normal CT imaging. There was no history of alcohol intake or intoxication. Management: Following acute management and stabilisation, he was admitted under the Endocrine and Diabetes team, who suspended his regular medications, including his ACE-I. As an inpatient, he underwent extensive biochemical investigations which were unremarkable followed by a prolonged 72 hours fasting test and an Oral Glucose Tolerance Test, wherein no significant drop in Blood Glucose was noted in both. Subsequently, there were no further episodes of hypoglycaemia and he remained asymptomatic whilst off his ACE-I and he was safely discharged. He was followed up in our Endocrine clinic and was found to have no episodes of Hypoglycaemia since discharge and remained asymptomatic. Discussion: We report the rare presentation of recurrent hypoglycaemia in a non- diabetic secondary to ACE-I. Hypoglycaemia may be defined by the Whipple’s triad, a classical triad of hypoglycaemic symptoms, low Blood Glucose levels and relief of symptoms following ingestion of glucose. The mechanism by which ACE-I treatment leads to hypoglycaemia remains unclear. It has been postulated that ACE-I related alterations in the Kininogen-Kinin system, are associated with hypoglycaemia. This mechanism may lead to an increase in Insulin sensitivity, mediated by increased muscle tissue uptake and diminished hepatic glucose production. Another proposed mechanism is the suppressive effect that ACE-inhibitors exhibit on the peripheral sympathomimetic overactivity, thus causing Hypoglycaemia. Exacerbating factors comprise of concurrent renal impairment, as in this case. The first case of ACE-I induced Hypoglycaemia was reported in 1985, with the usage of Captopril. To the best of our knowledge, this is one of the rare peculiar cases wherein an ACE-I has been implicated as the underlying aetiology causing Hypoglycaemia in a Non-Diabetic.

The thin films of Ni and Cu have been deposited on SiO2/Si(100) substrates in a thermal evaporator. The graphene layers have been grown on Ni-Cu films under C2H2-H2-Ar plasma under vacuum annealing condition in ICP-CVD.

Drought is one of the extreme climatic events among the most relevant natural disasters. This paper presents drought assessment using Standardized Precipitation Index SPI to overview the respective drought hot spots. Monthly rainfall data during the previous 36 years 1982 - 2017 are applied to generate Standardized Precipitation Index SPI with 3 month and 9 month scale on the basis of Gamma distribution for the areas in the central dry zone of Myanmar namely Mandalay, Nyaung U, Myingyan, Natogyi, Meikhtila, Kyaukpadaung, Wundwin, Sagaing, Monywa, Shwebo, Myinmu, Magway, Minbu, Chauk and Pakokku. The generated SPI values for different time scale are classified to assess drought hot spots for the central dry zone, Myanmar as an areal extent of annual drought. Aye Aye Thant "Drought Assessment Using Standard Precipitation Index" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-5 , August 2018, URL: https://www.ijtsrd.com/papers/ijtsrd18181.pdf

[Purpose] The present study aimed to determine the effects of a task-oriented training on paretic upper extremity functional performance in patients with subacute stroke. [Participants and Methods] Twenty-eight subacute stroke sufferers (mean age: 50.07, standard deviation 9.31 years; mean time since stroke 11.11, standard deviation 6.73 weeks) were randomly allocated to task-oriented training (n=14) or conventional exercise program (n=14) group. They were trained as a hospital-based, individualized training 1 hour a session, 5 sessions a week for 4 weeks. Wolf Motor Function Test (primary outcome), motor portion of Fugl-Meyer assessment upper extremity, and hand function domain of Stroke Impact Scale were assessed at baseline, after 2 and 4 weeks of training. [Results] All participants completed their training programs. At all post-training assessments, the task-oriented training group showed significantly more improvements in all outcomes than the conventional exercise program group. No serious adverse effects were observed during or after the training. [Conclusion] Task-oriented training produced statistically significant and clinically meaningful improvements of paretic upper extremity functional performance in patients with subacute stroke. These beneficial effects were observed after 2 weeks (10 hours) of training. Future investigation is warranted to confirm and expand these findings.

Summary Objective To determine the incidence of post‐stroke seizures and the associated risk factors in a government‐restructured hospital in Singapore. Methods This retrospective study included consecutive patients (age ≥21 years) admitted to the stroke rehabilitation facility at Changi General Hospital, Singapore, between June 2008 and May 2017, with a minimum post‐discharge follow‐up of 6 months. Patients with known epilepsy central nervous system infection or tumor, a history of neurosurgery and or missing data were excluded from study. To determine the incidence of seizures, the patients’ hospital records, including those for all initial and subsequent admissions and outpatient follow‐ups, were reviewed. All prescribed medications were checked and documented. Seizures were diagnosed on the basis of clinical examination with or without electroencephalography. Results In total, 722 patients (women, 38%) with a mean age of 64 years were included. Of these, 48 (6.64%) experienced post‐stroke seizures during a follow‐up period of 6–108 months. The incidence of seizures was significantly higher in patients with hemorrhagic stroke (42%, p = 0.010), those with ischemic partial anterior circulation stroke (PACS) (27%, p = 0.025), those who underwent a neurosurgical procedure after stroke (p

Hydroxyapatite (HAp) has been used extensively in medical applications for repair or replacement of bone tissues in human body system. It is chemically similar to the mineral component of bone and teeth and will form an artificial bone-like structure with the surrounding bone tissue when implanted. However, sintered hydroxyapatite material exhibits relatively poor mechanical properties than natural bone and as such, improvement of mechanical properties are necessary. One of the candidate materials for the reinforcing phase to HAp is zirconia, ZrO 2 . Medical applications of ZrO 2 implants confirmed their satisfactory biocompatibility, although it cannot bond well to bone tissue. In this study, ZrO 2 /HApbiocomposites were fabricated with the objective to improve the strength and toughness of the biomaterial. Commercial CaO-ZrO 2 (CZ) was selected as the reinforced material to the HAp matrix. Small amounts of CaF 2 were added to improve sinterability and the phase stability of these biocomposites. Conventional ceramic processing route was used to prepare ZrO 2 /HAp samples, which involved milling and mixing, compaction and sintering. X-ray diffraction (XRD), linear shrinkages, density and porosity, flexural strength, Vickers microhardness, toughness, and scanning electron microscopy (SEM) were used to characterize the (ZrO 2 /HAp) biocomposites. XRD results indicate phase stability of biocomposites to a temperature of 1200 °C. Shrinkage of fired samples were very uniform with increasing temperature, with slightly lower shrinkage in thickness direction. In general, strength of the reinforced ZrO 2 /HAp was successfully increased from 35.70 MPa to 52.88 MPa and the toughness was increased from 0.65 MPa.m 1/2 to 1.33 MPa.m 1/2 as well.

In this study, microstructured CaO-based adsorbents were synthesized by a sol–gel hydrothermal method using calcium nitrate tetrahydrate, citric acid and sodium hydroxide as precursors. Experiments with different NaOH concentrations (2, 6 and 10 M) were carried out to investigate the effects on the morphologies and CO2 adsorption activities of the synthesized adsorbents. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FESEM) results showed that different NaOH concentrations resulted in different crystal phases and morphologies. A novel three-dimensional (3D) hierarchical calcite (CaCO3) hollow microspherical adsorbent composed of one-dimensional (1D) spike-shaped nanorods was obtained with 2 M NaOH. XRD analyses confirmed that the hierarchical CaCO3 hollow microspheres were characteristic of the calcite phase. The FESEM image revealed that the microspheres were composed of 1D spike-shaped nanorods with an average length of 500 nm. The cross-sectional FESEM image showed that the microspheres had hollow structures with an average inner cavity of 2 μm and a shell thickness of approximately 0.5 μm. The CO2 adsorption performance of the synthesized adsorbents was investigated using thermogravimetry-differential thermal analysis (TG-DTA) apparatus. The results indicated that the novel hierarchical calcite (CaCO3) hollow microspherical adsorbent composed of one-dimensional (1D) spike-shaped nanorods possessed higher carbonation conversion of 45% after 15 cycles, which was about 22% higher than that of other adsorbents synthesized with 6 and 10 M NaOH concentration and limestone. This property could be attributed to the 3D hierarchical hollow microsphere structure, 1D spike-shaped nanorod structure, trimodal pore size distribution and large BET surface area (44.85 m2 g−1) of the novel adsorbent.

A novel high-efficiency (Zr–Ce) incorporated Ca(OH) 2 nanostructure adsorbent for CO 2 capture was synthesized using calcium acetate monohydrate precursor containing n-hexadecyltrimethyl ammonium bromide and sodium hydroxide via a precipitation method. The cyclic carbonation/calcination performance of the novel adsorbent was investigated using a thermogravimetry-differential thermal analysis (TG-DTA) apparatus. The novel (Zr–Ce) incorporated Ca(OH) 2 adsorbent exhibited a significantly improved CO 2 adsorption capacity, cyclic stability and remarkable carbonation conversion up to ~96% for 14 carbonation/calcination cycles compared with the pure Ca(OH) 2 adsorbent. This result may be due to the large Brunauer–Emmett–Teller (BET) surface area (80.23 m 2 /g), the wide range of mesopore size distribution (2–30 nm) and the presence of the high temperature sintering resistance Ce 2 Zr 3 O 10 compound of the novel adsorbent.

In this paper, one dimensional nanorod CaCO3 adsorbents were synthesized via hydrothermal method by varying the amount of polyacrylamide (PAM). The XRD results indicated that all of the characteristic peaks of synthesized adsorbents were matched well with the aragonite CaCO3 phase. FE-SEM analysis showed one dimensional nanorod structures with diameter of 40 - 70 nm and lengths up to micrometer. TG results exhibited CaCO3 adsorbents synthesized with 0.4 and 0.6 g of polyacrylamide possessed high CO2 adsorption capacities for first carbonation/calcination cycle (0.86 and 0.79 g-CO2/g-sorbent) which were higher than the theoretical CO2 adsorption capacity (0.78 g-CO2/g-sorbent) of calcium oxide based adsorbents.

Inkjet printing of conductive ink on flexible substrates is emerging as an attractive technology for wide variety applications. In this study, graphene and silver nanoparticles (AgNPs) conductive inks were printed on polyvinyl alcohol (PVA) substrates by inkjet printer. Effect of different solvents, printing cycles and annealing time on the performance of conductive ink was investigated. Three different groups of solvents were used to prepare the conductive ink; deionized water (DI): ethylene glycol (EG): glycol (G), isopropyl alcohol (IA): ethylene glycol (EG): glyceol (G) and dimethylformamide (DMF): Ethylene glycol (EG): Glyceol (G). DMF: EG: G solutions produced conductive ink with higher stability, wettability and electrical conductivity compared to other conductive ink formulations. It was observed that increased of printing cycles (from 1 to 5) times and annealing time (from 0 to 30) min had increase the electrical conductivity. During stretching, graphene conductive ink on PVA substrate shows lower electrical conductivity reduction compared to that of AgNPs conductive ink. Flaky shape of graphene able to maintain the conductive paths under loading condition.

To capture carbon dioxide (CO2), a major green house gas from flue gas, several kinds of adsorbents have been synthesized, characterized and tested. In this study, CaO-based adsorbents were synthesized via sol-gel-hydrothermal method and different hydrothermal temperatures (100, 120, 140 and 160 °C) have been investigated in order to verify their influence on the CaO-based adsorbents. Experimental results showed that the Ca(OH)2 adsorbent with a mixture of CaCO3 synthesized at 120 °C hydrothermal treatment possesses high CO2 adsorption capacity (0.52 g-CO2/g-sorbent) and at 160 °C hydrothermal treatment, CaC2O4.H2O adsorbent was observed and its CO2 adsorption capacity was 0.46 g-CO2/g-sorbent for first carbonation/calcination cycle.

A novel solution combustion method has been used to prepare Mg-Mn ferrites of various compositions, Mg0.9Mn0.1Fe1-xO4 where x = 0.2, 0.4, 0.6, 0.8, and the properties were investigated in the present work. Nano-size Mg-Mn ferrite particles with diameter in the range of 8~ 15 nm were successfully formed via this method. The combustion temperature of the oxidation-reduction was apparently occurred at 200°C. The result of X-ray diffraction (XRD) analysis indicated that the as-burnt powder affords a pure single spinel ferrite phase at low temperature. The thermal analysis of nitrate–citrate gels was characterized by DTA-TG. The TEM and SEM observations give the morphology and microstructure of the products. The dielectric properties of the sintered Mg-Mn ferrites were investigated by using HP/Agilent 4291B RF impedence/material analyzer. It was found that there was no maximum dielectric loss within the measured frequency range until 1 GHz due to excellent compositional control in this method.

Magnesuim Manganese ferrite powders of Mg 0.9 Mn 0.1 Fe 2-x O 4 [x = 0.2, 0.4, 0.6, 0.8] compositions were synthesized by citrate precursor method at low temperature. The decomposition temperature, phase formation and microstructure were characterized by Thermogravimetrical Analysis (TGA), X-ray diffraction method (XRD) and field emission scanning electron microscopy (FESEM), respectively. The density and porosity of sintered pellets were measured by Archimedes' method. The synthesized powders showed fine agglomerated particles with the crystallite size in the range of 15–25 nm. The size of the particle was found to decrease with Fe content. The XRD results of the calcined powders at 500°C for all compositions revealed the formation of single phase cubic spinel structure. The grain size of the pellets sintered at 1250°C was in the range of ~ 0.05 to 0.08 μm which is smaller than that obtained for ferrites prepared by the conventional ceramic method. The observed variations in magnetic properties were investigated by Vibrating Sample Magnetometer (VSM) and the results of magnetization exhibit collinear ferromagnetic behavior. This synthesis method is relatively simple, economical, time and energy saving for mass production.

In this study, Graphene has been synthesized by using electrochemical exfoliation method. Effect of sonication times (15, 30 and 45 min) at room temperature on the production of graphene was investigated. The synthesized graphene were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Atomic Force Microscopy (AFM). The crystal structure of the exfoliated graphene were analyzed using XRD. The graphene flakes exhibit a sharp peak centered at 26.5°corresponding to the (002) plane of graphene crystal. It is found that, the crystallite sizes is gradually decreased with increased in sonication time. The FTIR spectrum reveals the prominent appearance of C-O-H group which indicate that OH− radicals exist in conjunction with exfoliated graphene sheets. Graphene flakes with average thickness of 0.2 nm to 0.8 nm were observed using AFM. The electrical conductivity results showed that 45 min sonication time produced the highest electrical conductivity (1.38×102sm−1).

The present study elucidates the synthesis of magnesium ferrite magnetic nanocrystallites via hydroxylation–condensation reaction followed by an auto-combustion process. Nanocrystallites with diameter of 3–7 nm were successfully formed via this method. The ignition temperature of the redox reaction was apparently improved to 200°C by the modification of the pH of the metal aqueous solution. The crystallite size was altered by varying the hydrolysis parameters. The XRD analysis of the as-synthesized powder confirms the formation of a single-phase MgFe 2 O 4 spinel structure. Importantly, the crystalline particles were obtained at low temperature without further calcination. The thermodynamic behavior of the precursor was characterized by DTA-TG. TEM observations showed the morphology and crystal structure of the nanocrystallites.

Calcium hydroxide (Ca(OH)2) has been proposed as an important material for industrial, architectural, and environmental applications. In this study, calcium acetate was used as a precursor and cetyl trimethyl ammonium bromide (CTAB) was used as a surfactant to synthesize Ca(OH)2 based adsorbents for carbon dioxide (CO2) capture. The effect of CTAB concentration (0.2–0.8 M) on the structure, morphology and CO2 adsorption performance of Ca(OH)2 was studied in detail. The synthesized samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), BET surfaced area and thermogravimetry-differential thermal analysis (TG–DTA) techniques. The phase purity, crystallite size, Brunauer–Emmett–Teller (BET) surface area and CO2 adsorption performance of Ca(OH)2 precursor adsorbents were significantly increased when the concentration of CTAB was increased. XRD results showed that pure Ca(OH)2 phase was obtained at the CTAB concentration of 0.8 M. TGA results exhibited that 0.8 M of CTAB-assisted Ca(OH)2 precursor adsorbent possessed a residual carbonation conversion of ∼56% after 10 cycles.

We have previously reported that tumor necrosis factor-α (TNF-α) stimulation of CCKS1, a cell line established from cholangiocarcinoma with i.p. dissemination, dramatically increased matrix metalloproteinase-9 (MMP-9) production and tumor invasion. We investigated the role of focal adhesion kinase (FAK) in TNF-α–dependent production of MMP-9 in CCKS1 and FAK-null mouse fibroblast cells. TNF-α stimulation of CCKS1 or wild-type fibroblasts substantially activated FAK phosphorylation and increased MMP-9 production. In contrast, FAK-null fibroblasts could not respond well to TNF-α stimulation. Conditional expression of wild-type FAK in FAK-null cells restored the TNF-α–dependent production of MMP-9. TNF-α treatment activated the kinase activity of FAK and its phosphorylation especially at Y397 and Y925. Phosphorylated FAK accumulated at focal adhesions and formed a complex with growth factor receptor binding protein 2 and SOS. In contrast, Y397F FAK and Y925F FAK, whose Y397 and Y925 were replaced with phenylalanine, respectively, as well as KD FAK, whose kinase was inactivated, could not restore the MMP-9 production. In addition, small interfering RNA against FAK drastically suppressed the TNF-α–dependent production of MMP-9 and inhibited the TNF-α–dependent invasion of CCKS1. Taken together, our results suggest the pivotal role of FAK in TNF-α–dependent production of MMP-9 and subsequent activation of tumor invasion. (Cancer Res 2006; 66(13): 6778-84)

Background: Matrix metalloproteinases including MMP-9 mediate matrix destruction during chronic inflammatory diseases such as arthritis and atherosclerosis. MMP-9 up-regulation by inflammatory cytokines involve interactions between several transcription factors including activator protein-1 and NFκB. The upstream regulatory pathways are less well understood. Results: To search for the mechanism of tissue destruction in the process of inflammatory disorders, we investigated the signalling pathway critical for the activation of MMP-9 expression and secretion by IL-1β. Treatment of Balb 3T3 cells with IL-1β activated MMP-9 transcription and subsequent secretion in a time- and dose-dependent manner. Concomitantly, IL-1β treatment of cells activated phosphorylation of Akt, Erk and p38. Treatment of cells with either LY294002, a PI3K inhibitor, or expression of a dominant negative form of Akt drastically suppressed the IL-1β-dependent secretion of MMP-9. Pretreatment of cells with a MEK1 inhibitor, U0126, also strongly inhibited IL-1β-dependent secretion of MMP-9. In contrast, pre-treatment with a specific p38 kinase inhibitor, SB203580, had no effect on IL-1β-dependent secretion of MMP-9. In addition, cells expressing constitutively active form of Akt or MEK1 showed no clear activation of MMP-9 secretion, whereas these cells responded well to IL-1β treatment. However, co-transfection of cells with both active Akt and MEK1 was sufficient to induce MMP-9 secretion without stimulation with IL-1β. Conclusion: Taken together, our results suggest that IL-1β stimulation of cells activates MMP-9 secretion by the activation of the dual signalling pathways, the PI3K-Akt and MEK1-Erk and constitutive activation of these pathways were sufficient to induce MMP-9 secretion.

To evaluate the function of cysteine residues of the Src kinase, we constructed a series of Src mutants in which some of cysteines were replaced to alanines. With these mutants, we studied the effect of SH-alkylating agents, N-[p-(2-benzimidazolyl)phenyl] maleimide (BIPM) and N-(9-acridinyl) maleimide (NAM), on their kinase activity. Of 10 cysteine residues scattered over v-Src, either a single mutation at Cys520 or multiple mutations at the four clustered cyteines, Cys483, Cys487, Cys496 and Cys498, yielded clear resistance to the treatment with 10 microM BIPM or 1 microM NAM. In contrast, other cysteines including those in the SH2 domain and those in the catalytic cleft of the kinase domain were dispensable for the inactivation by BIPM and NAM. Similarly, deletion of SH2 and SH3 did not confer the resistance to v-Src, suggesting the inactivation by the SH-alkylating agents is SH2/SH3-independent. Although Cys520-mutated v-Src was resistant to 1 microM NAM, it was inactivated by 5 microM NAM. However, combined mutation including all of Cys483, Cys487, Cys496, Cys498 and Cys520 yielded clear resistance to 5 microM NAM. Among these mutants, those with double mutations in the four clustered cysteines yielded a temperature sensitive phenotype in the transfected cells, whereas Cys520 did not, suggesting that Cys520 has, at least in part, a discrete function. In contrast to v-Src, c-Src, which lacks cysteine at position 520, was resistant to 1 microM NAM but sensitive to 5 microM NAM. While replacement of Phe520 of c-Src to cysteine made it sensitive to 1 microM NAM, double mutation in clustered cysteines again yielded resistance to 5 microM NAM. Taken together, our results strongly suggest that the multiple cysteine residues clustered at the end of the C-terminal lobe are critical for the inhibition by the SH-alkylating agents and, thereby, have an allosteric repressor effect on the catalytic activity of Src in a SH2-phosphoTyr527 independent manner.

We investigated the role of SHPS-1/SIRPα1 in IL-1β- and TNFα-dependent signaling that leads to the activation of Erk 1/2 and Akt. Treatment of Balb3T3 cells with IL-1β or TNFα activated tyrosine phosphorylation of SHPS-1, its association with SHP-2 and the phosphorylation of Erk 1/2 and Akt. PP1, a specific inhibitor for the Src family protein tyrosine kinases, strongly inhibited tyrosine phosphorylation of SHPS-1 and complex formation of SHPS-1 with SHP-2 by IL-1β. In addition, PP1 substantially inhibited the IL-2β- and TNFα-dependent activation of Erk 1/2 and Akt. Exogenous expression of either SHPS-1 mutants that lack SHP-2 binding function or a dominant negative mutant of SHP-2 markedly inhibited the activation of Erk 1/2 and Akt by IL-1β, whereas wild type SHPS-1 did not. Moreover, IL-1β-stimulation induced association of SHPS-1 with IL-1RAcP, a second subunit of IL-1 receptor, whereas expression of SHPS-1 mutant that lack SHP-2 binding function clearly blocked the association and tyrosine phosphorylation of endogenous SHPS-1. Taken together, our results strongly suggest that activation of Erk 1/2 and Akt by proinflammatory cytokines requires tyrosine phosphorylation of SHPS-1 and subsequent association of SHPS-1 with SHP-2.

Hyluronan (HA), a nonsulfated high-molecular mass glycoaminoglycan, has been assigned as a clinical marker for the progression of various tumors. We found that HA stimulation of QG90, a cell line derived from human small-cell lung carcinoma, activates the secretion of matrix metalloproteinase-2 (MMP-2) in a focal adhesion kinase (FAK)-dependent manner. HA stimulation of QG90 cells activated MMP-2 secretion in a time-dependent manner. Larger sizes of HA seemed to have higher activities than smaller size one in MMP-2 secretion. Under HA stimulation, tyrosine phosphorylation of cellular proteins including FAK was activated. By use of antisense oligonucleotide to FAK, we found that FAK signaling was required for the activation of MMP-2 secretion and for the sustained activation of MAP kinase by HA treatment. These results strongly suggest that FAK-MAPK signaling is involved, at least in part, in HA-dependent activation of MMP-2 secretion in QG90 cells.

To study the signaling pathway critical for the secretion of matrix metalloproteinases (MMPs), we examined the role of focal adhesion kinase (FAK) in Concanavalin A (Con A)-stimulated cells. We established a cell line in which FAK gene was conditionally inducible by use of FAK-null fibroblasts and the tetracycline repression system. In this cell line, FAK expression was undetectable in the presence of tetracycline but induced within 1 day by the removal of the drug. We found that FAK expression augmented the Con A-dependent secretion of MMP-9 and MMP-2. In contrast, proteolytic activation of MMP-2 by Con A-treatment did not require FAK expression. In addition, activation of MMP-secretion and tyrosine phosphorylation of FAK by Con A, but not the proteolytic activation of MMP-2, required attachment of the cells to the extracellular matrix. Taken together, our results suggest that the FAK signaling pathway play a pivotal role in the secretion of MMPs.

We investigated the role of MEK1 signaling in MMP-2 activation by use of constitutive active/dominant negative forms of MEK1 and MEK1-specific inhibitor. We found that cell transformation with active forms of MEK1 dramatically increased secretion and proteolytic activation of MMP-2 and subsequently stimulated invasiveness of cells. Contrary, expression of dominant negative form of MEK1 in v-src-transformed cells or in Con A-activated cells resulted in the suppression of the augmented secretion and proteolytic activation of MMP-2. In addition, treatment of v-src-transformed cells with PD98059, a MEK1-specific inhibitor, strongly suppressed the secretion and activation of MMP-2, whereas treatment with wortmannin, a PI3 kinase inhibitor, showed no clear effect on MMP-2 secretion. Taken together, these results strongly suggest that MEK-MAP kinase signaling, but not PI3 kinase signaling, plays a critical role in the activation of MMP-2 secretion and, subsequently, in the invasiveness of v-src-transformed cells.

Cell adhesion to the extracellular matrix appears to trigger a cascade of intracellular signalings. We have previously shown that treatment of ovarian cancer cells, NOM1, with fibronectin (FN) stimulated matrix metalloproteinase (MMP)-9 secretion and thereby activated the invasiveness of cells via the FAK/Ras signaling pathway. By use of chemical inhibitors, we investigated the downstream effectors critical for FN-dependent secretion of MMP-9. Treatment of cells with MEK1 inhibitors, U0126 and PD98059, dramatically suppressed the secretion of MMP-9 activated by FN. Similarly, PI-3 kinase inhibitors, Wortmannin and LY294002, strongly suppressed the FN-dependent secretion of MMP-9 together with the inhibition of Akt activation. In contrast, a specific PKC inhibitor (GF109203X) showed no inhibitory effect on the FN-dependent MMP-9 secretion. Moreover, we found that both the MEK1 inhibitor and the PI3-K inhibitor, but not the PKC inhibitor, strongly suppressed the invasiveness of NOM1 cells. Taken together, our results suggest that activation of dual signaling pathways, MEK1-MAPK and PI3K-Akt, is required for the FN-dependent activation of MMP-9 secretion. Our results suggest the importance of these signaling molecules as a chemotherapeutic target for cancer.

To search for the signaling pathway critical for tumor invasion, we examined the effects of dominant negative ras (S17N ras) expression on the activation of matrix metalloproteinase-2 (MMP-2) in src-transformed 3Y1, SR3Y1, under the control of conditionally inducible promoter. In SR3Y1 clones transfected with S17N ras, augmented secretion and proteolytic activation of MMP-2 were dramatically suppressed by S17N Ras expression, while tyrosine phosphorylation of cellular proteins was not suppressed. We found that invasiveness of SR3Y1 cells assayed by the modified Boyden Chamber method was strongly suppressed by S17N Ras expression. In contrast, cell morphology reverted partially and glucose uptake remained unchanged by S17N Ras expression. In addition, treatment of SR3Y1 with manumycin A, a potent inhibitor of Ras farnesyltransferase, strongly suppressed both augmented secretion and proteolytic activation of MMP-2. Contrary, treatment of SR3Y1 with wortmannin or TPA showed no clear effect on MMP-2 activation. Thus, these results strongly suggest that Ras-signaling, but neither P13 kinase- nor protein kinase C-signalings, plays a critical role in activation of MMP-2 and, subsequently, in the invasiveness of src-transformed cells.

The mechanisms that could explain the poor sensitivity to 5-FU in certain colorectal cancer (CRC) cells were investigated and whether or not cotreatment with low doses of selenium would offer a therapeutic benefit was explored.Four CRC cell lines (Caco2, RKO, DLD1 and HT-29) with defined tumor signatures and seven different chemical forms of selenium were tested.5-FU partially inhibited the HT-29 and RKO cells, but had a weak effect on the DLD1 and almost none on the Caco2 cells. Selenous acid and sodium selenite induced growth inhibition of the DLD1, RKO and HT-29 cells, with a marginal effect on the Caco2 cells. The Caco2 cells with mutant p53, failure to activate caspase-8, -9, -7 and -3 and with hypermethylated caspase-8 were resistant to 5-FU. Conversely, RKO cells expressing wildtype p53, proteolytically activated caspase-8, -9, -7 and -3 and unmethylated caspase-8 were more responsive to 5-FU and selenous acid-induced apoptosis.Combination treatment with selenous acid may offer an efficacious strategy to overcome 5-FU resistance in certain CRC cells.

Matrix metalloproteinases including MMP-9 mediate matrix destruction during chronic inflammatory diseases such as arthritis and atherosclerosis. MMP-9 up-regulation by inflammatory cytokines involve interactions between several transcription factors including activator protein-1 and NFkappaB. The upstream regulatory pathways are less well understood.To search for the mechanism of tissue destruction in the process of inflammatory disorders, we investigated the signalling pathway critical for the activation of MMP-9 expression and secretion by IL-1beta. Treatment of Balb 3T3 cells with IL-1beta activated MMP-9 transcription and subsequent secretion in a time- and dose-dependent manner. Concomitantly, IL-1beta treatment of cells activated phosphorylation of Akt, Erk and p38. Treatment of cells with either LY294002, a PI3K inhibitor, or expression of a dominant negative form of Akt drastically suppressed the IL-1beta-dependent secretion of MMP-9. Pretreatment of cells with a MEK1 inhibitor, U0126, also strongly inhibited IL-1beta-dependent secretion of MMP-9. In contrast, pre-treatment with a specific p38 kinase inhibitor, SB203580, had no effect on IL-1beta-dependent secretion of MMP-9. In addition, cells expressing constitutively active form of Akt or MEK1 showed no clear activation of MMP-9 secretion, whereas these cells responded well to IL-1beta treatment. However, co-transfection of cells with both active Akt and MEK1 was sufficient to induce MMP-9 secretion without stimulation with IL-1beta.Taken together, our results suggest that IL-1beta stimulation of cells activates MMP-9 secretion by the activation of the dual signalling pathways, the PI3K-Akt and MEK1-Erk and constitutive activation of these pathways were sufficient to induce MMP-9 secretion.

We investigated the production of matrix metalloproteinase (MMP) by hyaluronan(HA) stimulation in a human cancer cell line, QG90, that expresses a large amount of CD44s, a HA receptor. Treatment of QG90 with HA strongly activated MMP-2 secretion in a time- and dose-dependent manner. We found that expression of antisense CD44s in QG90 cells substantially inhibited the HA-dependent secretion of MMP-2, whereas overexpression of full-length CD44s augmented the HA-dependent secretion of MMP-2. In addition, pretreatment of cells with the neutralizing anti-CD44 antibody significantly inhibited both the HA-dependent MMP-2 secretion and the HA-dependent activation of mitogen-activated protein kinase in a dose-dependent manner. Similarly, treatment of cells with a Ras farnesyltransferase inhibitor, manumycin A, strongly inhibited the HA-dependent MMP-2 secretion. Moreover, in vitro invasiveness of QG90 and its activation by HA were clearly suppressed by the expression of antisense CD44s. In addition, treatment of cells with anti-CD44, a mitogen-activated protein/extracellular signal-regulated kinase kinase 1 inhibitor, PD98059, or phosphatidylinositol 3'-kinase inhibitors, wortmannin and LY294002, effectively blocked the HA-dependent activation of the invasiveness. In contrast, overexpression of full-length CD44 substantially activated the invasiveness of QG90. Taken together, HA-CD44s signaling plays a key role in the HA-dependent secretion of MMP-2 and, hence, in the invasiveness of QG90 cells.

We investigated the role of SHPS-1/SIRPalpha1 in IL-1beta- and TNFalpha-dependent signaling that leads to the activation of Erk 1/2 and Akt. Treatment of Balb3T3 cells with IL-1beta or TNFalpha activated tyrosine phosphorylation of SHPS-1, its association with SHP-2 and the phosphorylation of Erk 1/2 and Akt. PP1, a specific inhibitor for the Src family protein tyrosine kinases, strongly inhibited tyrosine phosphorylation of SHPS-1 and complex formation of SHPS-1 with SHP-2 by IL-1beta. In addition, PP1 substantially inhibited the IL-2beta- and TNFalpha-dependent activation of Erk 1/2 and Akt. Exogenous expression of either SHPS-1 mutants that lack SHP-2 binding function or a dominant negative mutant of SHP-2 markedly inhibited the activation of Erk 1/2 and Akt by IL-1beta, whereas wild type SHPS-1 did not. Moreover, IL-1beta-stimulation induced association of SHPS-1 with IL-1RAcP, a second subunit of IL-1 receptor, whereas expression of SHPS-1 mutant that lack SHP-2 binding function clearly blocked the association and tyrosine phosphorylation of endogenous SHPS-1. Taken together, our results strongly suggest that activation of Erk 1/2 and Akt by proinflammatory cytokines requires tyrosine phosphorylation of SHPS-1 and subsequent association of SHPS-1 with SHP-2.