453 research outputs found
The role for CYCLIN A1;2/TARDY ASYNCHRONOUS MEIOSIS in differentiated cells in Arabidopsis
The Arabidopsis A1-type cyclin, CYCA1;2, also named TARDY ASYNCHRONOUS MEIOSIS (TAM), is known for its positive role in meiotic cell cycle progression, but its function in other cells has not been characterized. Here we report the role of TAM in cell differentiation in vegetative organs. The expression pattern of TAM was investigated by promoter and protein fusions using the β- glucuronidase (GUS) and the green fluorescent protein (GFP), respectively. Based on the expression pattern, morphologies of cells expressing TAM were studied in various plants including loss-of-function tam-1 and tam-2 mutants, a TAM-overexpression line, tam-1 complemented by the wild type TAM, and the wild-type. In addition, ploidy profiles in mature leaves of these plants were determined by flow cytometric analysis. TAM expression was found primarily in non-proliferating cells such as guard cells, trichomes, and mesophyll cells, and in vascular tissue, but its protein is kept at low levels. The tam mutants exhibited a reduction in trichome branch number but had a normal ploidy profile in the leaves. Compared to the wild type, these mutants also exhibited more pavement cell swelling, and the null allele, tam-2, had a larger average guard cell size but a normal ploidy level in the guard cells. Overexpression of TAM produced phenotypic changes opposite to those in the loss-of-function mutants, in addition to an increase in the relative portion of diploid cells. These results suggest that the primary role of TAM in vegetative organs is to regulate cell differentiation or cell turgidity in a cell-cycle-independent manner.Plant Biology, Ecology and Evolutio
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Efficacy and safety of ginsam, a vinegar extract from Panax ginseng, in type 2 diabetic patients: Results of a double‐blind, placebo‐controlled study
Abstract Aims/Introduction: The efficacy, dose–response relationship and safety of ginsam, a vinegar extract from Panax ginseng, were evaluated in an 8‐week, double‐blind, randomized, placebo‐controlled study in drug‐naïve patients with type 2 diabetes. Materials and Methods: A total of 72 diabetic patients were randomized to receive 1500, 2000 or 3000 mg of ginsam, or placebo daily for 8 weeks (n = 18 in each group). The primary end‐point was the changes from the baseline HbA1c level. The secondary end‐points were the changes of fasting and postprandial 2‐h glucose concentration, and the proportion of patients achieving a reduction in HbA1c >0.5%. Results: In the intention‐to‐treat analysis, ginsam treatment reduced HbA1c level significantly: −0.56 ± 0.25% in the 1500 mg group, −0.31 ± 0.12% in the 2000 mg group, and −0.29 ± 0.11% in the 3000 mg group (all P 0.5% differed significantly between the placebo group (11.1%) and the 1500 mg (27.8%) and 2000 mg (27.8%) groups. No severe adverse events were observed in any group. Conclusions: An 8‐week treatment with ginsam, a vinegar extract from P. ginseng, moderately improved HbA1c level and was well tolerated in type 2 diabetic patients with inadequate glycemic control. This trial was registered with ClinicalTrial.Gov (no. NCT01008163). (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2011.00185.x, 2011
Routine Shunting is Safe and Reliable for Cerebral Perfusion during Carotid Endarterectomy in Symptomatic Carotid Stenosis
Dispersion of Vascular Plant in Kumo-do, Korea
AbstractThe vascular plants observed in the area were composed of a total of 228 taxa; 72 families, 172 genus, 201 species, 25 varieties, 1 sub-species and 1 cross species. The only endangered plants found in the area were Milletia japonica (Siebold & Zucc.) A.Gray. The endemic plants growing in the Geumodo except transplanted plants were Lespedeza x maritima Nakai and Carpinus coreana Nakai. which accounted for 0.8% of the vascular plants in Geumodo, 228 taxa. Specialized plants of Geumodo were a total of 41 species; 30 taxa in Grade I, 1 taxon in Grade II, 9 taxa in Grade III and 1 taxon in Grade V. Milletia japonica (Siebold & Zucc.) A.Gray was the only species found in important Grade IV to V. Currently, ferries ply to the island, attracting many tourists. This poses a threat to the rare plants living in the island and presses down the island to develop. Therefore, in the long-term perspective, the conservation plan such as comprehensive research and monitoring on the ecosystem shall be established to protect evergreen broad-leaved forests
Antibacterial and synergistic effects of Nardostachytis rhizoma extracts on methicillin-resistant Staphylococcus aureus
Methicillin-resistant Staphylococcus aureus (MRSA) is a serious clinical problem worldwide. Few new drugs are available against MRSA, because it has the ability to acquire resistance to most antibiotics which consequently increases the cost of medication. In the present study, the antibacterial activity of Nardostachytis rhizoma was investigated. The most effective method is to develop antibiotics from the natural products without having any toxic or side effects. Therefore, there is a need to develop alternative antimicrobial drugs for the treatment of infectious diseases. The use of two drugs in combination is a good alternative to slow the process of developing drug resistance and to restore the effectiveness of drugs that are no longer prescribed. Combination therapy is the most commonly recommended empirical treatment for bacterial infections in intensive care units, where monotherapy may not be effective against all potential pathogens, and for preventing the emergence of resistant. Five clinical isolates (MRSA) were obtained from five different patients at Wonkwang University Hospital (Iksan, South Korea). The other two strains were S. aureus ATCC 33591 (methicillin-resistant strain) and S. aureus ATCC 25923 (methicillin-susceptible strain). Antibacterial activity (minimal inhibitory concentrations, MICs) was determined by broth dilution method, disc diffusion method, MTT test and checkerboard dilution test. Antimicrobial activity of n-hexane fraction of N. rhizoma was significant. Against the seven strains, the disc diffusion test was in the range of 14 to 18 mm and had a MICs ranging from 31.25 to 125 ìg/ml. FICI values for n-hexane fraction (HFL) of N. rhizome + ampicillin (AM) and HFL + oxacillin (OX) were 0.1875 and 0.078125-0.09375, showing the increase of synergistic effect. When combined together, these antibiotic effects were dramatically increased. These effective combinations could be new promising agents in the management of MRSA and MSSA.Key words: Nardostachytis rhizoma, synergism, antibacterial, methicillin-resistant Staphylococcus aureus (MRSA)
Android Fat Depot Is More Closely Associated with Metabolic Syndrome than Abdominal Visceral Fat in Elderly People
BACKGROUND: Fat accumulation in android compartments may confer increased metabolic risk. The incremental utility of measuring regional fat deposition in association with metabolic syndrome (MS) has not been well described particularly in an elderly population. METHODS AND FINDINGS: As part of the Korean Longitudinal Study on Health and Aging, which is a community-based cohort study of people aged more than 65 years, subjects (287 male, 75.9±8.6 years and 278 female, 76.0±8.8 years) with regional body composition data using Dual energy X-ray absorptiometry for android/gynoid area, computed tomography for visceral/subcutaneous adipose tissue (VAT/SAT), and cardiometabolic markers including adiponectin and high-sensitivity CRP were enrolled. We investigated the relationship between regional body composition and MS in multivariate regression models. Mean VAT and SAT area was 131.4±65.5 cm(2) and 126.9±55.2 cm(2) in men (P = 0.045) and 120.0±46.7 cm(2) and 211.8±65.9 cm(2) in women (P<0.01). Mean android and gynoid fat amount was 1.8±0.8 kg and 2.5±0.8 kg in men and 2.0±0.6 kg and 3.3±0.8 kg in women, respectively (both P<0.01). VAT area and android fat amount was strongly correlated with most metabolic risk factors compared to SAT or gynoid fat. Furthermore, android fat amount was significantly associated with clustering of MS components after adjustment for multiple parameters including age, gender, adiponectin, hsCRP, a surrogate marker of insulin resistance, whole body fat mass and VAT area. CONCLUSIONS: Our findings are consistent with the hypothesized role of android fat as a pathogenic fat depot in the MS. Measurement of android fat may provide a more complete understanding of metabolic risk associated with variations in fat distribution
Development of Monoclonal Antibodies Against Human IRF-5 and Their Use in Identifying the Binding of IRF-5 to Nuclear Import Proteins Karyopherin-α1 and -β1
PURPOSE: IRF-5 is a direct transducer of virus-mediated and TLR-mediated signaling pathways for the expression of cytokines and chemokines which form homodimers or heterodimers with IRF-7. However, direct IRF-5-specific monoclonal antibodies (mAbs) are not available at present. These could be used to further evaluate the functions of IRF-5. In this study, we produced and characterized three mouse mAbs to human IRF-5. The binding of IRF-5 to nuclear import proteins was first identified using a mAb.
MATERIALS AND METHODS: His-tagged human IRF-5 protein spanning amino acid residues 193-257 was used as an antigen and three mAbs were produced. The mAbs were tested with ELISA, Western blot analysis (WB), immunofluorescent staining (IF), and immunoprecipitation (IP). In addition, the nuclear import protein which carried phosphorylated IRF-5 was identified using one of these mAbs.
RESULTS: MAbs 5IRF8, 5IRF10 and 5IRF24 which reacted with the recombinant His-IRF-5(193-257) protein were produced. All mAbs bound to human IRF-5, but not to IRF-3 or IRF-7. They could be used for WB, IF, and IP studies. The binding of phosphorylated IRF-5 to karyopherin-alpha1 and -beta1 was also identified.
CONCLUSION: Human IRF-5-specific mAbs are produced for studying the immunologic roles related to IRF-5. Phosphorylated IRF-5 is transported to the nucleus by binding to nuclear import proteins karyopherin-alpha1 and -beta1.ope
Stemness Evaluation of Mesenchymal Stem Cells from Placentas According to Developmental Stage: Comparison to Those from Adult Bone Marrow
This study was done to evaluate the stemness of human mesenchymal stem cells (hMSCs) derived from placenta according to the development stage and to compare the results to those from adult bone marrow (BM). Based on the source of hMSCs, three groups were defined: group I included term placentas, group II included first-trimester placentas, and group III included adult BM samples. The stemness was evaluated by the proliferation capacity, immunophenotypic expression, mesoderm differentiation, expression of pluripotency markers including telomerase activity. The cumulative population doubling, indicating the proliferation capacity, was significantly higher in group II (P<0.001, 31.7±5.8 vs. 15.7±6.2 with group I, 9.2±4.9 with group III). The pattern of immunophenotypic expression and mesoderm differentiation into adipocytes and osteocytes were similar in all three groups. The expression of pluripotency markers including ALP, SSEA-4, TRA-1-60, TRA-1-81, Oct-4, and telomerase were strongly positive in group II, but very faint positive in the other groups. In conclusions, hMSCs from placentas have different characteristics according to their developmental stage and express mesenchymal stemness potentials similar to those from adult human BMs
Comparison between Matched Related and Alternative Donors of Allogeneic Hematopoietic Stem Cells Transplanted into Adult Patients with Acquired Aplastic Anemia: Multivariate and Propensity Score-Matched Analysis
We retrospectively compared the outcomes of 225 patients with adult acquired aplastic anemia (AA) who underwent allogeneic hematopoietic stem cell transplantation (alloHSCT) from matched related donors (MRDs), and those treated by alloHSCT from alternative donors (ADs). Univariate and multivariate analyses of factors associated with survival were performed. Multivariate analysis showed that age at alloHSCT of ≤31 years, MRD, successful engraftment, absence of acute graft-versus-host disease (aGVHD), and platelet engraftment at ≤21 days, were independent predictors of longer survival. In addition, time to aGVHD and cumulative nonrelapse mortality (NRM) were better in MRD than in AD recipients. Using propensity score matching (PSM), we performed a case-control study comparing 25 patients in each group who underwent alloHSCT from MRDs and ADs. Pretransplantation clinical factors were well balanced in either group. Median survival time was similar, and no statistically significant difference in transplantation outcomes was apparent when MRD and AD recipients were compared. In conclusion, our results suggest that alloHSCT from an AD should be considered earlier in adult patients with AA who do not have an MRD
A Role of Canonical Transient Receptor Potential 5 Channel in Neuronal Differentiation from A2B5 Neural Progenitor Cells
Store-operated Ca2+ entry (SOCE) channels are the main pathway of Ca2+ entry in non-excitable cells such as neural progenitor cells (NPCs). However, the role of SOCE channels has not been defined in the neuronal differentiation from NPCs. Here, we show that canonical transient receptor potential channel (TRPC) as SOCE channel influences the induction of the neuronal differentiation of A2B5+ NPCs isolated from postnatal-12-day rat cerebrums. The amplitudes of SOCE were significantly higher in neural cells differentiated from proliferating A2B5+ NPCs and applications of SOCE blockers, 2-aminoethoxy-diphenylborane (2-APB), and ruthenium red (RR), inhibited their rise of SOCE. Among TRPC subtypes (TRPC1-7), marked expression of TRPC5 and TRPC6 with turned-off TRPC1 expression was observed in neuronal cells differentiated from proliferating A2B5+ NPCs. TRPC5 small interfering RNA (siRNA) blocked the neuronal differentiation from A2B5+ NPCs and reduced the rise of SOCE. In contrast, TRPC6 siRNA had no significant effect on the neuronal differentiation from A2B5+ NPCs. These results indicate that calcium regulation by TRPC5 would play a key role as a switch between proliferation and neuronal differentiation from NPCs
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