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Inducing Factor (inducing + factor)
Selected AbstractsAdhesive papillae on the brachiolar arms of brachiolaria larvae in two starfishes, Asterina pectinifera and Asterias amurensis, are sensors for metamorphic inducing factor(s)DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 8 2007Naoyuki Murabe It has been hypothesized by Barker that starfish brachiolaria larvae initiate metamorphosis by sensing of metamorphic inducing factor(s) with neural cells within the adhesive papillae on their brachiolar arms. We present evidence supporting Barker's hypothesis using brachiolaria larvae of the two species, Asterina pectinifera and Asterias amurensis. Brachiolaria larvae of these two species underwent metamorphosis in response to pebbles from aquaria in which adults were kept. Time-lapse analysis of A. pectinifera indicated that the pebbles were explored with adhesive papillae prior to establishment of a stable attachment for metamorphosis. Microsurgical dissections, which removed adhesive papillae, resulted in failure of the brachiolaria larvae to respond to the pebbles, but other organs such as the lateral ganglia, the oral ganglion, the adhesive disk or the adult rudiment were not required. Immunohistochemical analysis with a neuron-specific monoclonal antibody and transmission electron microscopy revealed that the adhesive papillae contained neural cells that project their processes towards the external surface of the adhesive papillae and they therefore qualify as sensory neural cells. [source] Expression of chondrogenic potential of mouse trunk neural crest cells by FGF2 treatmentDEVELOPMENTAL DYNAMICS, Issue 2 2006Atsushi Ido Abstract There is a significant difference between the developmental patterns of cranial and trunk neural crest cells in the amniote. Thus, whereas cranial neural crest cells generate bone and cartilage, trunk neural crest cells do not contribute to skeletal derivatives. We examined whether mouse trunk neural crest cells can undergo chondrogenesis to analyze how the difference between the developmental patterns of cranial and trunk neural crest cells arises. Our present data demonstrate that mouse trunk neural crest cells have chondrogenic potential and that fibroblast growth factor (FGF) 2 is an inducing factor for their chondrogenesis in vitro. FGF2 altered the expression patterns of Hox9 genes and Id2, a cranial neural crest cell marker. These results suggest that environmental cues may play essential roles in generating the difference between developmental patterns of cranial and trunk neural crest cells. Developmental Dynamics 235:361,367, 2006. © 2005 Wiley-Liss, Inc. [source] Active c-jun N-terminal kinase induces caspase cleavage of tau and additional phosphorylation by GSK-3, is required for tau aggregationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2008Naruhiko Sahara Abstract Neurofibrillary tangles (NFTs), comprising human intracellular microtubule-associated protein tau, are one of the hallmarks of tauopathies, including Alzheimer's disease. Recently, a report that caspase-cleaved tau is present in NFTs has led to the hypothesis that the mechanisms underlying NFT formation may involve the apoptosis cascade. Here, we show that adenoviral infection of tau into COS-7 cells induces activation of c-jun N-terminal kinase (JNK), followed by excessive phosphorylation of tau and its cleavage by caspase. However, JNK activation alone was insufficient to induce sodium dodecyl sulfate (SDS)-insoluble tau aggregation and additional phosphorylation by GSK-3, was required. In SH-SY5Y neuroblastoma cells, overexpression of active JNK and GSK-3, increased caspase-3 activation and cytotoxicity more than overexpression of tau alone. Taken together, these results indicate that, although JNK activation may be a primary inducing factor, further phosphorylation of tau is required for neuronal death and NFT formation in neurodegenerative diseases, including those characterized by tauopathy. [source] Elevation of interleukin-18 in chronic hepatitis C: implications for hepatitis C virus pathogenesisIMMUNOLOGY, Issue 1pt2 2009Arpita Sharma Summary The outcome of hepatitis C virus (HCV) infection is determined by the interplay between the virus and the host immune response. Interleukin (IL)-18, an interferon-,-inducing factor, plays a critical role in the T helper type 1 (Th1) response required for host defence against viruses, and antibodies to IL-18 have been found to prevent liver damage in a murine model. The present study was conducted to investigate the possible role of IL-18 in the pathogenesis and persistence of HCV. IL-18 levels were measured in sera of 50 patients at various stages of HCV infection (resolved, chronic and cirrhosis) and compared with those of normal controls. IL-18 gene expression was studied in peripheral blood mononuclear cells (PBMC) from each group, and in liver biopsy tissue from patients with chronic hepatitis C. The mean levels of IL-18 in sera were markedly elevated in patients with chronic hepatitis and cirrhosis, and were reduced in patients with resolved HCV infection. The serum IL-18 concentrations were related to the Child,Pugh severity of liver disease in cirrhotic patients. There also existed a strong positive correlation of IL-18 levels with histological activity score and necrosis. IL-18 mRNA expression was significantly up-regulated in the PBMC of cirrhotic patients when compared with other groups, while in the liver, higher levels of IL-18 transcripts were expressed in patients with chronic hepatitis C. The results of our study indicate that IL-18 levels reflect the severity and activity of HCV infection, and may contribute to the pathogenesis and progression of liver disease associated with HCV. [source] Induction of cytotoxicity in human lung adenocarcinoma cells by 6- O -carboxypropyl-,-tocotrienol, a redox-silent derivative of ,-tocotrienolINTERNATIONAL JOURNAL OF CANCER, Issue 5 2005Yoshihisa Yano Abstract Tocotrienols are one of the most potent anticancer agents of all natural compounds and the anticancer property may be related to the inactivation of Ras family molecules. The anticancer potential of tocotrienols, however, is weakened due to its short elimination half life in vivo. To overcome the disadvantage and reinforce the anticancer activity in tocotrienols, we synthesized a redox-silent analogue of ,-tocotrienol (T3), 6- O -carboxypropyl-,-tocotrienol (T3E). We estimated the possibility of T3E as a new anticancer agent against lung adenocarcinoma showing poor prognosis based on the mutation of ras gene. T3E showed cytotoxicity against A549 cells, a human lung adenocarcinoma cell line with a ras gene mutation, in a dose-dependent manner (0,40 ,M), whereas T3 and a redox-silent analogue of ,-tocopherol (T), 6- O -carboxypropyl-,-tocopherol (TE), showed much less cytotoxicity in cells within 40 ,M. T3E cytotoxicity was based on the accumulation of cells in the G1-phase of the cell-cycle and the subsequent induction of apoptosis. Similar to this event, 24-hr treatment of A549 cells with 40 ,M T3E caused the inhibition of Ras farnesylation, and a marked decrease in the levels of cyclin D required for G1/S progression in the cell-cycle and Bcl-xL, a key anti-apoptotic molecule. Moreover, the T3E-dependent inhibition of RhoA geranyl-geranylation is an inducing factor for the occurrence of apoptosis in A549 cells. Our results suggest that T3E suppresses Ras and RhoA prenylation, leading to negative growth control against A549 cells. In conclusion, a redox-silent analogue of T3, T3E may be a new candidate as an anticancer agent against lung adenocarcinoma showing poor prognosis based on the mutation of ras genes. © 2005 Wiley-Liss, Inc. [source] Dermatomyositis presenting as panniculitisINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 2 2000Yen-Yu Chao MD A 44-year-old obese woman was transferred to our clinic with a diagnosis of panniculitis. Examination showed multiple, indurated, erythematous, painful nodules and plaques distributed on the shoulders, back, forechest, abdomen, buttock, and bilateral thighs. These skin lesions appeared 2 months previously, measured 5,8 cm, and were tender on palpation. No obvious inducing factor was traced. The lesions seemed unresponsive to treatment with nonsteroidal anti-inflammatory drugs (ibuprofen, 400 mg three times a day) as similar lesions appeared in subsequent visits. Progressive proximal muscle weakness was found 1 month later. She was then admitted via the emergency room because of extensive painful skin plaques and abdominal pain. Diffuse erythematous to violaceous swelling of the face, neck, and shoulder was noted at about the same time ( Fig. 1). A skin biopsy specimen from the nodular lesion showed poikilomatous epidermal changes ( Fig. 2), and marked mononuclear cell infiltration in the dermis and subcutaneous fat ( Fig. 3). Dermatomyositis was considered as the diffuse violaceous facial erythema could be a form of heliotrope eruption, but Gottron's papule was not found. At admission, serum creatinine phosphokinase (CPK) was mildly elevated (436 IU/L; normal range, 20,170 IU/L), but serum asparagine transaminase (AST) and lactate dehydrogenase (LDH) levels were within normal limits (36 IU/L; normal, 11,47 IU/L; and 108 IU/L; normal, 90,280 IU/L, respectively). Antinuclear antibody was 1 : 80 positive with an atypical speckled pattern. Muscle strength was weakest during the first 2 days, about grade 3 by the Medical Research Council (MRC) of Great Britain scale. Gower's sign was positive. An electromyogram showed myopathic changes and a nerve conduction velocity study was normal. Serum enzymes were elevated further on the third day: AST, 55 IU/L; CPK, 783 IU/L with 100% MM form. The diagnosis of dermatomyositis was established. As for the work-up result, anti-dsDNA antibody, anti-ENA antibody, and anti-Jo1 antibody were negative. Tumor marker screen (,-HCG, AFP, CEA, and CA-125), was negative, and rhinolaryngopharyngoscope examination and gynecologic sonography were normal. Figure 1. Diffuse erythematous swelling with subtle violaceous hue extending from the temporal area to the cheeks, neck, and shoulders. The crusted lip ulcers of herpes simplex were also noted Figure 2. Basketweave hyperkeratosis, mild acanthosis, subtle vacuolar degeneration of the basal cells, and melanin incontinence (hematoxylin and eosin, ×400) Figure 3. Heavy mononuclear cells infiltrated in the subcutaneous fat tissue (hematoxylin and eosin, ×100) Pancreatitis was initially suspected because of epigastric pain and tenderness, elevated serum lipase (382 U/L; normal, 23,200 U/L), and amylase (145 U/L; normal, 35,118 U/L). No evidence of pancreatitis could be found in abdominal sonography and abdominal computed tomography (CT), however. The epigastric pain and tenderness subsided soon after admission and the serum pancreatic enzyme level declined on the second day (amylase 69 U/L; lipase, 276 U/L). The patient was then diagnosed with dermatomyositis and treated with prednisolone (120 mg/day). CPK dropped dramatically from 3286 IU/L the day before treatment to 1197 IU/L 3 days after. Panniculitis lessened and the muscle power improved after 1 week of treatment. The disease activity fluctuated even with treatment with prednisolone and the patient often felt listless and weak. The muscle weakness sometimes deteriorated to affect the patient's mobility. Facial erythema and panniculitis-like lesions were found during the worse times. Methotrexate and azathioprine were then added (7.5 mg and 250 mg per week, respectively), but CPK was still mildly elevated (189 IU/L), and the patient still felt ill. Human immune globulin (5%, 500 mL per day, 5 days per month) intravenous infusion was initiated thereafter. There was a dramatic response. Full muscle strength was retained and CPK was within the normal range in the following 6 months with only immune globulin therapy. [source] Identification of the agent from Lactobacillus plantarum KFRI464 that enhances bacteriocin production by Leuconostoc citreum GJ7JOURNAL OF APPLIED MICROBIOLOGY, Issue 6 2007J.Y. Chang Abstract Aim:, To provide evidence that the production of bacteriocin by lactic acid bacteria can be enhanced by the presence of a bacteriocin-sensitive strain and identify the agent that is responsible for enhancing bacteriocin production. Methods and Results:, One bacteriocin-producing lactic acid bacterium was isolated from kimchi. The strain GJ7 was designated as Leuconostoc citreum GJ7 based on Gram staining, biochemical properties, and 16S rRNA gene sequencing. The isolate produced a heat- and pH-stable bacteriocin (kimchicin GJ7), which has antagonistic activity against a broad spectrum of micro-organisms. Tricine-sodium dodecyl sulfate-polyacrylamide gel electrophoresis of purified kimchicin GJ7 showed a single band of molecular weight c. 3500 Da. Cultures of Leuc. citreum GJ7 in the presence of thermally inactivated kimchicin GJ7-sensitive strains, Lactobacillus plantarum KFRI 464, Lactobacillus delbrueckii KFRI 347, or Leuconostoc mesenteroides KCTC 1628, increased bacteriocin production. This inducing factor was characterized and purified from Lact. plantarum KFRI 464, which showed the greatest enhancement of kimchicin GJ7 activity. The inducing factor was purified using a DEAE (diethyl aminoethyl)-Sephacel column and high-performance liquid chromatography, and yielded a single band of c. 6500 Da. N -terminal sequencing of the inducing factor identified 16 amino acids. The N -terminal sequence of the inducing factor was synthesized and examined for the induction of kimchicin GJ7 activity, and was found to induce activity, but at a level about 10% lower than that of the entire molecule. Conclusions:, The presence of a bacteriocin-sensitive strain, Lact. plantarum KFRI 464, acts as an environmental stimulus to activate the production of kimchicin GJ7 by Leuc. citreum GJ7. The inducing factor from Lact. plantarum KFRI 464 is highly homologous to the 30S ribosomal protein S16 from various micro-organisms. The N -terminal sequence of the inducing factor examined in this study is a very important sequence related to the inducing activity. Nevertheless, the inducing factor may not be part of the ribosomal protein S16 itself. Significance and Impact of the Study:, We believe that the present study is the first to identify an agent that is produced by one micro-organism and influences bacteriocin production in another. The bacteriocin-enhancing system described in this study could be effectively used to control the growth of other micro-organisms (sensitive cells) in food systems. Moreover, this enhancement of bacteriocin production can be applied usefully in industrial production of natural food preservatives. [source] Differentiation inducing factors in Dictyostelium discoideum: A novel low molecular factor functions at an early stage(s) of differentiationDEVELOPMENT GROWTH & DIFFERENTIATION, Issue 9 2009Akiko A. Oohata There are reports that secreted factor(s) are involved in prespore cell differentiation in Dictyostelium discoideum, but the structures and functions of the various factors have not been elucidated. Previously, we described two prespore cell-inducing factors in conditioned medium; one was a glycoprotein named prespore cell-inducing factor (, factor, or PSI-1), and the other, a heat stable dialyzable factor(s). In the present paper, we purified and characterized the most potent prespore cell-inducing activity in dialysates. The factor began to be secreted after the onset of starvation and stopped being secreted once the cells had aggregated, which was earlier than the onset of the , factor gene expression. In addition, unlike , factor, its secretion did not appear to depend on activation of protein kinase A. Interestingly, the purified factor not only induced prespore cell specific genes such as pspA and cotC but also a prestalk-cell specific gene, ecmB in vitro. The purified factor is tentatively designated polyketide-like factor (PLF), because it seems to be a novel polyketide with 208 Da. Half maximal induction of prespore cell was obtained with 26 nmol/L of PLF. We propose that PLF plays a key role in the acquisition of differentiation commitment, before the , factor induces specifically prespore cell differentiation. [source] Iron availability affects mcyD expression and microcystin-LR synthesis in Microcystis aeruginosa PCC7806ENVIRONMENTAL MICROBIOLOGY, Issue 10 2008Emma Sevilla Summary Microcystins are toxins produced by cyanobacteria that entail serious health and environmental problems. They are cyclic heptapeptides synthesized via a mixed polyketide synthase/non-ribosomal peptide synthetase system called microcystin synthetase. Environmental and nutritional factors that trigger microcystin synthesis are still debated and this work deals with the study of the influence of iron nutritional status on the microcystin synthesis. The results indicate that iron deficiency could be one of the inducing factors of the microcystin synthesis. For the first time, increased transcription of an essential mcy gene and correlative microcystin synthesis has been established. Real-time PCR analysis of mcyD, and microcystin-LR synthesis were studied on Microcystis aeruginosa PCC7806 grown in iron-replete and iron-deplete media. Iron starvation causes an increase of mcyD transcription, correlative to the increase of microcystin-LR levels. Four transcription start points were identified for mcyD and two for mcyA, and they are not changed as a consequence of iron deficiency. [source] Were volatile organic compounds the inducing factors for subjective symptoms of employees working in newly constructed hospitals?ENVIRONMENTAL TOXICOLOGY, Issue 4 2004Tomoko Takigawa Abstract This study demonstrated possible relationships between environmental, personal, and occupational factors and changes in the subjective health symptoms of 214 employees after the relocation of a hospital in a region of Japan. Eight indoor volatile organic compounds (VOCs) were detected in at least one of the 19 rooms investigated, and total VOC (TVOC) concentrations in 8 rooms exceeded the advisable value (400 ,g/m3) established by the Ministry of Health, Labour and Welfare of Japan. Formaldehyde was detected in all the investigated rooms, but none of the results exceeded the guideline value (100 ,g/m3). Multiple logistic regression analysis was applied to select variables significantly associated with the subjective symptoms that can be induced by sick building syndrome. The results showed that subjective symptoms of deterioration in the skin, eye, ear, throat, chest, central nervous system, autonomic system, musculoskeletal system, and digestive system among employees were associated mainly with gender difference and high TVOC concentrations (>1200 ,g/m3). Long work hours (>50 h per week) in females and smoking in males were to be blamed for the deterioration of their symptoms. The present findings suggest that to protect employees from indoor environment-related adverse health effects, it is necessary to reduce the concentration of indoor chemicals in new buildings, to decrease work hours, and to forbid smoking. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 280,290, 2004. [source] The role of irregular unit, GAAS, on the secondary structure of Bombyx mori silk fibroin studied with 13C CP/MAS NMR and wide-angle X-ray scatteringPROTEIN SCIENCE, Issue 8 2002Tetsuo Asakura Abstract Bombyx mori silk fibroin is a fibrous protein whose fiber is extremely strong and tough, although it is produced by the silkworm at room temperature and from an aqueous solution. The primary structure is mainly Ala-Gly alternative copolypeptide, but Gly-Ala-Ala-Ser units appear frequently and periodically. Thus, this study aims at elucidating the role of such Gly-Ala-Ala-Ser units on the secondary structure. The sequential model peptides containing Gly-Ala-Ala-Ser units selected from the primary structure of B. mori silk fibroin were synthesized, and their secondary structure was studied with 13C CP/MAS NMR and wide-angle X-ray scattering. The 13C isotope labeling of the peptides and the 13C conformation-dependent chemical shifts were used for the purpose. The Ala-Ala units take antiparallel ,-sheet structure locally, and the introduction of one Ala-Ala unit in (Ala-Gly)15 chain promotes dramatical structural changes from silk I (repeated ,-turn type II structure) to silk II (antiparallel ,-sheet structure). Thus, the presence of Ala-Ala units in B. mori silk fibroin chain will be one of the inducing factors of the structural transition for silk fiber formation. The role of Tyr residue in the peptide chain was also studied and clarified to induce "locally nonordered structure." [source] Gene profiling and pathway analysis of neuroendocrine transdifferentiated prostate cancer cellsTHE PROSTATE, Issue 1 2009Ryutaro Mori Abstract BACKGROUND Neuroendocrine (NE) cells are present in both normal prostate and prostate cancer. In addition, NE differentiation can be induced by various factors, such as IL-6, in vitro and in vivo. However, the mechanism of this differentiation and the role of NE cells in prostate cancer are not well understood. In this study, we evaluated the gene expression and analyzed the pathways in prostate cancer cells exposed to various NE differentiation inducing factors in vitro. METHODS Gene expression signatures between control LNCaP cells and each treatment induced NE cell line were compared using Affymetrix GeneChip with network and pathway analysis. RESULTS All treatments were able to transdifferentiate LNCaP cells into NE phenotype as shown by morphology changes and NE marker measurements. Of the 54,675 oligonucleotide-based probe sets in microarray, 44,975 were mapped into the Ingenuity Pathway Analysis database and were filtered according to the t -test P value. At P,<,0.002, the number of genes that were differentially expressed included 302 of the IL-6 treated cells, 201 of genistein, 233 of epinephrine, and 191 of the charcoal stripped serum ones. A pooled data approach also showed 346 differentially expressed genes at the same P value. Gene ontology analysis showed that cancer-related function had the highest significance. CONCLUSIONS Despite some overlap, each NE transdifferentiation inducing treatment was associated with a changed expression of a unique set of genes, and such gene profiling may help to elucidate the molecular mechanisms involved in NE transdifferentiation of prostate cancer cells. Prostate 69: 12,23, 2009. © 2008 Wiley,Liss, Inc. [source] Association of neuropeptides with Th1/Th2 balance and allergic sensitization in childrenCLINICAL & EXPERIMENTAL ALLERGY, Issue 11 2006G. Herberth Summary Background Among neurogenic factors, the neuropeptides have an important regulatory influence on immune system activity and may lead to allergic sensitization. Objective The aim of our study was to investigate the relationship of the neuropeptides vasoactive intestinal peptide (VIP), somatostatin (SOM) and substance P (SP) on modulation of Th1/Th2 balance and allergic sensitization in children. Methods Within the LISAplus (Life style,Immune system,Allergy) study, blood samples of 321 six-year-old children were analysed for concentration of neuropeptides, Th1 and Th2 cytokines, transcription factors for T cell regulation and suppressors of cytokine signalling. In addition, samples were screened for specific IgE against inhalant and food allergens. Results Children with high SOM values showed a Th2 polarization and a reduced expression of FOXP3, the marker for regulatory T cells. High (VIP) levels correlated inversely with the expression of T cell transcription factors (Tbet and SOCS3). In contrast, elevated levels of SP were associated with reduced GATA3 and SOCS3 expression and with increased IFN-, concentrations. Allergic sensitization was more prevalent in children with higher SOM and VIP concentrations but not associated with SP levels. Conclusion Our data reveal an association between neuropeptides and modulatory effects on immune cells in vivo, especially on Th1/Th2 balance with a correlation to allergic sensitization in children. We suggest that elevated SOM and VIP concentrations and the inducing factors should be considered as allergy risk factors. [source] | |||||||||||||