235 , P < 0.05), β3 (correlation coefficients were 0. 333 , P < 0.01 ) subunits. Discussion Chemotherapy resistance has been proven to be a very difficult issue in the treatment of ovarian cancer. The mechanisms of resistance and appropriate countermeasures targeting these mechanisms have become hotspots in ovarian cancer research. Previous Liproxstatin-1 price studies of the mechanism of resistance in ovarian cancer mainly focused on drug concentration in tumor cells, DNA damage repair mechanisms, glutathione-dependent detoxification enzyme system activity, and other aspects. In recent years, a number of studies on malignant tumor drug resistance have found

that tumor drug resistance is related to changes in adhesion molecule composition, the adhesion abilities of tumor cells, and the resultant cytoskeletal rearrangements and signal transduction pathway activation. Therefore, a new mechanism of tumor drug resistance—cell adhesion mediated drug resistance (CAM-DR) has been proposed [2–4]. The adhesion of tumor cells to the surrounding environment can improve cell survival and anti-apoptotic ability. Integrins are important cell surface adhesion molecules as they are

receptors for many extracellular matrix components. Integrin receptors can regulate cell growth, differentiation, and metastasis through selleck inhibitor transmembrane signal transduction. Tumor cell growth and metastasis are both closely related to drug resistance. Metastasized tumor cells are more likely to be drug resistant and resistant tumor cells have a stronger ability to metastasize or invade. The relationship between integrins and drug resistance

is gradually gaining Thiamet G recognition, but the research is still in early stages [7–9]. Damiano et al [10] found that the expression of integrin α4β1 in the drug-resistant strain, RPMI8226/S, of human multiple myeloma cell strain RPMI8226 was significantly higher than that in sensitive strains; furthermore, extracellular matrix-coated cells significantly increased the cells’ tolerance of the chemotherapeutic drugs melphalan and doxorubicin and reduced the rate of apoptosis. Similar findings have been observed for leukemia, glioma, breast cancer and small cell lung cancer. In preliminary studies, we have also demonstrated that the ovarian cancer cell line, RMG-I-h, with high expression of the integrins α5β1 and αvβ3, can ABT-263 cost increase drug resistance to 5-FU, carboplatin, and paclitaxel [11, 12]. Integrin glycosylation status has been shown to affect the strength of integrin-ligand binding and the formation of the glycosidic bond catalyzed by glycosyltransferase affecting the glycosylation status of integrins.

(PDF 341 KB) Additional file 3: Francisella tularensis subsp. holarctica isolates belonging to B.Br.013 group used in this study. Lists NAU strain ID, original ID, date, and geographic location of isolates used in this study. (XLS 35 KB) Additional file 4: Francisella tularensis MLVA genotype data presented as repeat size. (XLS 20 KB) References 1. Dennis DT, Inglesby TV, Henderson DA: Tularemia as a biological weapon: medical and public health management. Working group on Civilian Biodefense. JAMA

2001, 285:2763–2773. 15 other authorsPubMedCrossRef 2. Huber BE, Escudero R, Busse HJ, Seibold E, Scholz HC, Anda P, Kampfer P, Splettstoesser WD: Description of Francisella hispaniensis sp. nov ., isolated from human blood, reclassification Y-27632 mouse of Francisella novicida (Larson et al. 1955) Olsufiev et al. 1959 as Francisella tularensis subsp. novicida comb. nov ., and emended description of the genus Francisella . Int J Syst Evol Microbiol 2009. 3. Keim P, Johansson A, Wagner DM: Molecular epidemiology, evolution, and ecology of Francisella . Ann N Y Acad Sci 2007, 1105:30–66.PubMedCrossRef 4. Johansson A, Celli J, Conlan W, Elkins KL, Forsman M, Keim PS, Larsson P, Manoil C, Nano FE,

Petersen JM, Sjostedt A: Objections to the transfer of Francisella novicida to the subspecies rank of Francisella tularensis . Int J Syst Evol Microbiol 2010, 60:1717–1718. author reply 1718–1720PubMedCrossRef 5. Staples JE, Kubota KA, Chalcraft LG, Mead PS, Petersen

JM: Epidemiologic and molecular analysis of human tularemia, United States, 1964–2004. Emerg ML323 price ATM inhibitor Infect Dis 2006, 12:1113–1118.PubMed 6. Svensson K, Larsson P, Johansson D, Byström M, Forsman M, Johansson A: Evolution of subspecies of Francisella tularensis . J Bacteriol 2005, 187:3903–3908.PubMedCrossRef 7. Johansson A, Farlow J, Larsson P, Dukerich M, Chambers E, Byström M, Fox J, Chu M, Forsman M, Sjöstedt A, Keim P: Worldwide genetic relationships among Dynein Francisella tularensis isolates determined by multiple-locus variable-number tandem repeat analysis. J Bacteriol 2004, 186:5808–5818.PubMedCrossRef 8. Farlow J, Wagner DM, Dukerich M, Stanley M, Chu M, Kubota K, Petersen J, Keim P: Francisella tularensis in the United States. Emerg Infect Dis 2005, 11:1835–1841.PubMed 9. Petersen JM, Molins CR: Subpopulations of Francisella tularensis ssp. tularensis and holarctica : identification and associated epidemiology. Future Microbiol 2010, 5:649–661.PubMedCrossRef 10. Gurcan S, Karabay O, Karadenizli A, Karagol C, Kantardjiev T, Ivanov IN: Characteristics of the Turkish isolates of Francisella tularensis . Jpn J Infect Dis 2008, 61:223–225.PubMed 11. Chitadze N, Kuchuloria T, Clark DV, Tsertsvadze E, Chokheli M, Tsertsvadze N, Trapaidze N, Lane A, Bakanidze L, Tsanava S, Hepburn MJ, Imnadze P: Water-borne outbreak of oropharyngeal and glandular tularemia in Georgia: investigation and follow-up. Infection 2009, 37:514–521.PubMedCrossRef 12.

Mouse antibodies (CD44-FITC αv-APC and β3-PE) were all purchased

from BD Biosciences. All the stained samples were analyzed in a Calibur instrument (BD Biosciences, CA) and data were analyzed in FCS express software (De Novo, CA). Whole lungs were collected from treated animals and were preserved in formalin and embedded in paraffin. Sections of lungs were stained with Hematoxylene and Eosin staining (H&E) to evaluate efficacy of different treatments on the growth of lung tumors. Plasma samples were collected when mice were euthanized at the end of in vivo study and mouse OPN VX-680 manufacturer was measured by an ELISA kit (R&D System, MN) using a protocol provided by the manufacturer. Tumor implantation KrasG12D-LSLp53fl/fl mice (n = 10) were inhaled intranasally with Adeno-CMV-Cre (2.5 × 10^7 viral particles, University

of Iowa, IO). Using trocar catheter, pieces of tumors were removed from the lungs at 16 weeks post-inhalation and were immediately implanted subcutaneously in Scid/beige mice. Tumor bearing mice (n = 10) were randomized at 8 days post-implantation when tumors reached 200 mm3 using caliper measurement [35]. Randomized animals were treated with vehicle, Carboplatin (25 mg/kg weekly, Hospira, IL), AOM1 (30 mg/kg weekly) and combination of both compounds using intra-peritoneal route of administration. The entire study was terminated when vehicle-treated tumors PRI-724 order reached ~2500 mm3. Whole lungs were fixed in formalin, embedded in paraffin and were cut using a microtome machine in the laboratory. Slides from each treatment were stained in H&E (hetoxylin and eosin) and metastasis in each section was assessed by a certified pathologist. Lung lesions were quantified based on size of tumors to small (less than 10 cells) medium (10-200) and large (more than 200 cells). Results Development and characterization of AOM1 monoclonal antibody targeting mouse and human OPN Analysis of aa (amino-acid) sequences of three different isoforms of OPN (a, b and c) provided some clue about

common regions between the isotypes in order to identify antibodies potentially capable of binding and neutralizing all forms of OPN (Figure 1A). Consistent with a published report [36], there PJ34 HCl is a conserved aa sequence in all three isoforms corresponding to binding sites for a series of integrins including α4β1, α4β7, α9β1, α9β4, αvβ3, αvβ1, αvβ5, αvβ5, α5β1 and α8β1 making it an attractive epitope to SB-715992 mouse target with an anti-OPN neutralizing antibody. Screening of phage display libraries identified several antibodies with the potential to bind to the integrin biding sequence of OPN. Further detailed biochemical and cellular characterization led to the discovery of AOM1, a fully human monoclonal antibody with the ability of neutralizing both human and mouse OPN. Species specificity of AOM1 was determined by SPR (surface plasmon resonance) using OPN immobilized on a Biacore chip. AOM1 was found to cross-react with human and mouse OPN (Figure 1.B).

At least three experiments were performed, and results from a representative experiment performed in

triplicates are shown. Error bars indicate standard deviation and sometimes fall within the data label. We assayed the resistance of the ΔarcA mutant E. coli to hydrogen peroxide (H2O2). TGF-beta inhibitor Overnight culture of the ΔarcA mutant E. MAPK inhibitor coli was exposed to H2O2, and its survival was compared to that of the wild type E. coli. The ΔarcA mutant E. coli was more susceptible than the wild type E. coli (Figure 1A). Plasmid pRB3-arcA, which carries a wild type allele of arcA in plasmid pRB3-273C [38, 40], complemented the survival defects in H2O2. This indicates that the susceptible phenotype of the ΔarcA this website mutant E. coli was likely due to the deletion of the arcA allele (Figure 1A). Assays

performed with log-phase culture of the ΔarcA mutant E. coli yielded similar results (data not shown). Similar results were obtained with LB broth and M9 minimal medium, results obtained with LB broth are shown (Figure 1). The same analysis was carried out for ArcB, the cognate sensor-kinase of the ArcAB system. The ΔarcB mutant E. coli survived less than the wild type parental strain (Figure 1C). We had attempted to clone a wild type allele of arcB into plasmid pRB3-273C to complement the ΔarcB mutant E. coli. However, the cloning efficiency was unusually low as compared to similar cloning attempts we had conducted with the plasmid vector. Of a total of 7 recombinant plasmids we eventually obtained from several transformations, 5 contained mutations at the start codon of arcB and the remaining 2 had mutations that produced truncations early in the ORF (data not shown). This indicates that an over-expression of arcB from a plasmid is probably toxic to E. coli. As an alternative, we constructed a revertant of of the ΔarcB mutant E. coli, in which a wild type arcB allele replaced the deleted arcB allele (see Materials and Methods). The revertant mutant of ΔarcB was shown to have the same resistance to H2O2 as the wild type E. coli (Figure 1C). The ArcAB system is dispensable for H2O2 scavenge To determine the mechanism of how the ArcAB system is involved

in H2O2 resistance, we analyzed the H2O2 scavenging activity of the ΔarcA and ΔarcB mutant of E. coli K12, since a defect in H2O2 scavenging activity may lead to the susceptibility to H2O2. The overnight culture was diluted in LB containing 2 mM of H2O2, and the concentration of the residual H2O2 was measured after various incubation period. The scavenge of H2O2 was measured as the reduction in H2O2 concentration over the incubation period. Our results indicate that both ΔarcA and ΔarcB mutants scavenged H2O2 normally as compared to the wild type E. coli K12., and no deficiency was observed (Figure 2). Figure 2 The ArcAB system is dispensable for H 2 O 2 scavenge. The ΔarcA (square), ΔarcB (triangle) mutant and the wild type E.

MT performed the immunogold labelled electron microscopy and contributed to writing the manuscript. CF contributed to the construction of mutants and writing of the manuscript. AGM contributed to the design of experiments and writing of the manuscript. MAS conceived click here the study and wrote the manuscript. All authors read and approved the final manuscript.”
“Background Deoxynivalenol (DON; vomitoxin) is a secondary metabolite produced by some Fusarium species of fungi. DON belongs to the trichothecene group of mycotoxins characterized by the 12,13-epoxy-trichothec-9-ene ring system. It has been shown that the 12,13-epoxide

group on the trichothecene nucleus of DON is mainly responsible for its toxicity [1, 2]. The toxin causes clinical symptoms including feed refusal, vomiting, lesions in the gastrointestinal tract, immunosuppression and lack of muscle coordination in domestic

animals [2–4]. DON contamination often occurs when weather is conducive to the infection of cereal crops by Fusarium fungi and this website is commonly found worldwide on corn, wheat, barley, and other grains. Contamination of grains by DON poses an increasingly serious threat to U0126 livestock production and human health. Despite a plethora of information regarding the biochemistry, toxicity, and modes of action of mycotoxins, it still remains a challenge to control/eradicate DON either pre- or post- harvest [5]. The industries are facing an even greater challenge due to the increased incidence of Fusarium ear rot of corn and the competition for corn from the emerging biofuel industry [6]. Therefore, effective methods to control mycotoxin contamination are urgently needed. The prevention of mycotoxin production and detoxification of mycotoxins are the two main strategies for control of mycotoxin contamination. While physical and chemical

techniques have been largely used to detoxify DON, breeding Methocarbamol for Fusarium-resistant plants and preharvest use of fungicides are the main strategies for the prevention [7]. Biological detoxification has also been a choice for postharvest treatment because of its advantages in efficiency, specificity, and environmental soundness. A de-epoxy metabolite of DON, resulting from enzymatic reduction of the 12,13-epoxy-group to a diene, was identified from rat urine and faeces and first described by Yoshizawa et al. [8]. The de-epoxy DON, called dE-DON or DOM-1 in the literature, has been proven to be much less toxic than DON [2, 9, 10]. Biotransformation of DON by microbial cells or enzymes is particularly attractive [11–13]. In the past two and half decades, transformation of DON by mixed microorganisms from animal intestines has been studied [5]. One significant study showed that DON incubated in vitro with the contents of the large intestine of chicken (CLIC) disappeared within 24 hr [14].

19 (1.38-3.47) 0.22 1.24 (0.11-13.84) – 2.15 (1.37-3.38) 0.27 1.07 (0.10-11.89) –    Mixed 1 58/528 1.44 (0.79-2.64) – 1.35 (0.30-6.11) – 1.43 (0.80-2.56) – 1.22 (0.27-5.48) – a Number of comparisons b P value of Q-test for heterogeneity test. Random-effects model was used if the P value <0.10; otherwise, fixed-effects model was used Publication bias Begg's funnel plot was used to identify the potential publication bias of literatures on breast cancer, and the results did not show any evidence of publication bias in any comparison model (P > 0.05). Discussion Previous studies have inconclusive results about the EPZ015938 association between ATM D1853N polymorphism and breast cancer

risk, which might be caused by relatively small sample size in a single study. Meta-analysis offers a rational and helpful way to solve this practical problem by combination the findings from Nutlin-3a clinical trial independent studies. In the current meta-analysis, we cumulated the data from nine case-control studies to explore the association between ATM D1853N polymorphism and breast cancer risk. No significant association between this polymorphism and breast cancer risk was observed

in the overall study populations. Our result was consistent with the finding from a previous meta-analysis showing that another polymorphism of ATM (S49C, rs1800054) was not significantly associated with breast cancer susceptibility [28]. This finding indicates that the ATM D1853N polymorphism is not a risk factor for developing breast cancer, although a significantly increased risk

of breast cancer in ATM-heterozygous carriers has been reported [1, 13–18]. Wortmannin in vitro After subgroup analyses according to ethnicity, we found that the ATM D1853N polymorphism was associated with a significantly increased risk of breast cancer in South American population (heterozygote comparison and dominant model) but not in European and mixed populations. The reason for these discrepancies is not very clear. There are, however, some possible Ergoloid reasons. Firstly, the ATM D1853N polymorphism may present with different frequencies in different populations and as a result may be associated with different degrees of breast cancer risk among different ethnic populations. Secondly, the genotype distribution in the controls of a South American study was departed from Hardy-Weinberg equilibrium [27], indicating that there was a high risk of selection bias because the controls may not be representative of the general population very well. Thirdly, the positive association might have occurred by chance due to the insufficient statistical power with only two South American studies eligible in this meta-analysis [27, 29]. Therefore, additional studies with larger sample size are of great importance to clarify this finding. Some limitations of this meta-analysis should be taken into consideration.

Table 1 Results obtained in the comparative trial by the real-time PCR and the reference culture method a, b. Sample typec No. of samples % Valued κe   N PA NA FN TP FP AC SE SP   Minced meat 60 30 30 0 0 0 100 100 100 1.00 Poultry neck-skins 60 27 31 0 2 0 97 107 100 0.97 Pig carcass swabs 120 21 98 1 0 0 99 95 100 0.97 TOTAL 240 78 159 1 2 0 99 103 100 0.97 a PA: Positive Agreement, NA: Negative Agreement, TP: True Positive, FN: False Negative, FP: False Positive, AC: Relative Accuracy, SE: Relative Sensitivity,

SP: Relative Specificity, N = PA +NA + FN + TP + FP. b Results are given after confirmation. c Matrices as defined by NordVal [15]; matrix meat: minced meat BAY 63-2521 concentration (raw pork and veal) and poultry neck skins, matrix environmental samples: pig carcass swabs. Meat samples were artificially contaminated and swab samples potentially naturally contaminated. d See Materials and ARS-1620 clinical trial methods for accuracy, sensitivity and specificity equations. e Cohen’s kappa calculated according to NMKL procedure no. 20 [26]. The detection level of the two methods was 1–10 CFU/25 g sample

(corresponding to a relative detection level of 100%) in all cases except for the swabs inoculated with S. Enteritidis, selleck chemicals where it was 10–100 CFU/25 g for the NMKL method (relative detection level > 100%) (data not shown). To determine the relative accuracy, sensitivity and specificity, a total of 240 samples representing meat and environmental samples were analyzed by the PCR and NMKL methods (Table 1). A total of 80 out of 240 samples gave positive results by real-time PCR, compared Staurosporine with a total of 79 by the culture-based method. Two samples showed positive deviation (true positives by the PCR method) and one negative deviation (false negative by the PCR method) (Table 1). A very good agreement between the two methods was obtained using Cohen’s kappa (Table 1). Collaborative trial The purpose of the collaborative

trial was to determine the variability in the results obtained by the real-time PCR method detecting Salmonella in identical samples. The trial was conducted in accordance with the guidelines provided by NordVal [15]. The samples and the other contents of the ring trial kit sent out to the participants were found to be stable during the period of the trial (data not shown). The influence of the refrigerated transit was investigated prior to the collaborative trial, and no detrimental effects were found after three days (data not shown). Six laboratories participated in the collaborative trial, and valid results were obtained from five of the laboratories and used for the statistical analysis (Table 2). In agreement with the predefined criteria, results from one participant were excluded due to failure in the PCR analysis (lack of amplification in the positive control and several samples with no amplification of either the target or the IAC).

985 ± 3.446). The difference between the knowledge scores of the first year students and fourth year students was found to be statistically significant (p = .000). Discussion The present study investigated the nutrition knowledge of students receiving sport education in universities considering whether they took nutrition class (1st and 4th year students) and gender. Most of the participant students were

both continuing their university education and pursuing sports life in various clubs. In addition to the Cell Cycle inhibitor energy and food elements needed by regular university students, there are some extra requirements for sports type of these students. It is considered that people with inadequate knowledge of nutrition will also be unaware of additional nutrient needs. Over half of the participants (56.3%) CB-839 supplier correctly answered the statement “”eating carbohydrates makes learn more you fat”"

as false. In another study, the majority of males (74.0%) and females (75.0%) correctly answered the same statement. The response to the statement of carbohydrates and the relationship between carbohydrates and body fat are encouraging, as many believe that those trying to improve body composition should avoid carbohydrates [7]. The sportsmen are inclined to think that sweets would provide quick energy just before competition. This prejudice may lead to rely on candy to provide the energy that should come from complex carbohydrates. The underlying goal of eating candies before exercise is to boost energy and minimize insulin surge that transports sugar out of the bloodstream into the muscles. Simple sugars induce high insulin, and when used before exercise, this can lower the blood sugar and elicit the fatigue as well as lightheadedness associated with hypoglycemia [11, 12]. A big proportion

of the students (72.3%) correctly answered the statement “”basic sugars like cube sugar, jam, and honey are the most suitable energy sources for sportsmen”" as false. Carbohydrates are the source of muscle energy followed very by fats and proteins, whereas vitamins, minerals, and water are also essential for health but do not provide energy [13]. It is important for athletes to consume enough carbohydrates to maintain blood glucose and to replace glycogen stores [14, 15]. Over half of the participants (61.2%) correctly answered the statement “”glycogen muscles store carbohydrate”". In a study carried out by Juzwiak and Ancona-Lopez [10], an important part of the participants (74.0%) gave correct answers to the statement “”glycogen levels (stored carbohydrate) can affect the energy level available for exercise”". The majority of the participant students (77.8%) answered the statement “”protein is the main energy source for the muscle”" as false. In the previous studies on this matter, the rates of people with correct knowledge changed between 28.0% and 54.0% [7, 8, 10, 16]. The athletes should be informed about the fact that proteins are not the main energy source for the muscles.

This forest type is commercially the most valuable for timber extraction. Most lowland dipterocarp forest in the Philippines has been logged (ESSC 1999) and the NSMNP Wortmannin manufacturer was established to protect one of the last larger remnants in the country. (3) Ultrabasic (also AZD0156 ic50 called ultramafic) forest is found on soils which contain high concentrations of heavy metals and that are deficient in phosphorus, potassium and calcium (Proctor 2003). This forest type is poorly described and understood. Generally, shortage of nutrients and presence of toxic soils lead to stunted tree growth but there is great variation in species composition,

species richness and forest structure between ultrabasic forests in different

sites (Proctor 2003). www.selleckchem.com/products/ly2835219.html In the NSMNP, ultrabasic forest is found on a large exposed ophiolite (uplifted oceanic crust) along the eastern margin of the park (Andal et al. 2005) at elevations from sea level up to 1,100 m. At all elevations, canopy height is generally low at around 15 m, but with great variation and at some locations emergent trees reach 40 m. Tree densities were very high with 12,500–16,500 individuals per hectare in two study plots (Fortus and Garcia 2002a, b). (4) Montane forest (also called mossy forest as trees are often covered with bryophytes and filmy ferns) is generally found at elevations over 800 m, but on smaller mountains and exposed ridges descends to as low as 500 m. Dipterocarpaceae no longer occur here. Myrtaceae and Fagaceae are numerically the most common families. The

canopy rarely exceeds 20 m and on exposed mountain ridges is lower than 5 m in height. Tree densities in this forest type were 5,740–8,684 individuals per ha in three study plots (Garcia 2002d). Fig. 1 Main forest types in the NSMNP and the locations of survey plots; letters about refer to tree survey plots, numbers to bird and bat survey plots, codes as in Appendix 1. Cut-off in West and East is arbitrary, in North and South follows provincial boundaries. Inset shows location of NSMNP in Isabela Province in the Philippines. Map based on NAMRIA (1995), NORDECO and DENR (1998), Carranza et al. (1999), Andal et al. (2005), and ground validation by the first author The NSMNP also has small areas of beach forest along the coast, freshwater swamp forest in areas that are flooded a large part of the year and forest on limestone soils (Co and Tan 1992). Data on these latter forest types were not available in sufficient detail and these forest types have not been included in the analyses here. In addition, several areas in the park have been converted to agricultural lands, grassland or shrub-land. Data used in this paper were gathered within the framework of the Dutch funded NSMNP-Conservation Project (1996–2002) and the Cagayan Valley Program on Environment and Development (CVPED 2002–2006).

Large number of hydrated electrons and H• atoms are produced during radiolysis of aqueous solutions by irradiation (Equation 1). They are strong reducing agents with redox potentials of and E0 (H+/H•) = -2.3 VNHE, respectively [30]. Therefore, they can reduce metal ions into zero-valent metal particles (Equations 2 and 3).

(1) (2) (3) This mechanism avoids the use of additional reducing agents and the following side reactions. Moreover, by varying the dose of the irradiation, the amount of zero-valent nuclei can be controlled. On the other hand, hydroxyl radicals (OH•), induced in radiolysis of water, selleck products are also strong reducing agents with E0 = (OH•/H2O) = +2.8 VNHE, which could oxidize the ions or the atoms into a higher oxidation state. An OH• radical scavenger, such as primary or secondary alcohols or formate ions, is therefore added into the precursor solutions before irradiation. For example, isopropanol can scavenge OH• and H• radicals and selleck at the same time changes into the secondary radicals, which eventually reduce metal ions (M+) into zero-valent atoms (M0) as shown in the following reactions [24]: (4) (5) (6) Multivalent ions are also reduced up to the atoms, by multi-step processes

possibly including Protein Tyrosine Kinase inhibitor disproportion of lower valence states. These processes are illustrated by a schematic diagram in Figure 1. Figure 1 Scheme of metal ion reduction in solution by ionizing radiation in the presence of stabilizer. The isolated atoms M0 coalesce DNA ligase into clusters. They are stabilized by ligands, polymers, or supports [24]. Nucleation and growth under irradiation The hydrated electrons arising from the radiolysis of water can easily reduce all metal ions up to the zero-valent atoms (M0). Also, the multivalent metal ions could be reduced by multi-step reductions including intermediate valencies. The atoms, which are formed via radiolytic method, are distributed homogeneously throughout the solution.

This is as a result of the reducing agents generated by radiation which can deeply penetrate into the sample and randomly reduce the metal ions in the solution. These newly formed atoms act as individual centre of nucleation and further coalescence. The binding energy between two metal atoms or atoms with unreduced ions is stronger than the atom-solvent or atom-ligand bond energy [24]. Therefore, the atoms dimerize when encountering or being associated with the excess metal ions: (7) (8) The charged dimer clusters M2 + may further be reduced to form a centre of cluster nucleation. The competition between the reduction of free metal ions and absorbed ones could be controlled by the rate of reducing agent formation [31]. Reduction of ions which are fixed on the clusters favours to cluster growth rather than formation of new isolated atoms.