This study further showed that tumors excised from the EA-treated

This study further showed that tumors excised from the EA-treated mice revealed increased inhibitory phosphorylation of the insulin receptor substrate 1 (IRS1) and decreased activity of the Cytoskeletal Signaling inhibitor PI3/AKT pathway, in line with our in vitro results in A498 cells. Based on their in vitro results, the authors of this study concluded that EA bound and activated PKCθ to inhibit insulin signaling while, concurrently, activating HSF1, a known inducer of selleck chemicals glucose dependence,

thus, starving cells of glucose while promoting glucose addiction. However, because the in vitro binding studies with EA and PKCθ were indirect without any binding kinetic analyses, it is unclear if PKCθ is a primary target of EA. Furthermore, the experiments demonstrating inhibition of glucose uptake by EA were performed using EA at 10 μM, a concentration of EA approximately 200-fold higher than its IC50. It is well established that when cells are starved, the energy sensor, AMP-activated protein kinase, becomes activated by phosphorylation resulting in the induction of autophagy. If EA inhibits glucose uptake, it would be expected to result in a higher ADP/ATP and AMP/ATP ratio and consequent activation of AMPK. Our results, however, did not reveal activation of AMPK by EA at a concentration of 100 nM, a concentration that is highly cytotoxic to A498 cells. Hence, it is possible that the effects

of EA on glucose uptake may occur at micro molar concentrations that are much higher than required for cell death (nanomolar) and could represent off-target effects. Moreover, as a natural product, EA would be expected to have multiple VX-661 mw targets and most likely has targets in addition to PKCθ. Such targets may include those associated with the ER stress since it is well established that ER stress results in the induction of cell death and autophagy [49]. An example

of agent that induces autophagy and cell death by inducing ER stress in RCC includes STF-62247 which targets VHL-deficient RCC [50]. EA may target proteins within the Golgi complex analogous oxyclozanide to carminomycin I, a natural product with selective toxicity to VHL-deficient CC-RCC [51]. In conclusion, EA induces cell death via multiple mechanisms and likely has multiple cellular targets. The identification of these targets and pathways affected by this unique agent will be invaluable in understanding the high RCC- selectivity of EA and allow development of highly effective chemotherapeutics for the treatment of metastatic RCC, a highly treatment resistant cancer. Acknowledgment We gratefully acknowledge Dr. Stoyan Dimitrov for his assistance with the flow cytometry studies. This work was supported by a fund from Academia Sinica (A. L. Yu) and, in part, by an NIH grant (CA 133002) awarded to Emmanuel Theodorakis. References 1. Nguyen MM, Gill IS, Ellison LM: The evolving presentation of renal carcinoma in the United States: trends from the Surveillance, Epidemiology, and End Results program.

The first nested PCR consisted of 30 ng of genomic DNA, 0 05 μl o

The first nested PCR consisted of 30 ng of genomic DNA, 0.05 μl of Hot start taq (5 unit/μl, Promega), 1 mM of each dNTP,

4 μl of reaction buffer (Promega), 1 μl of each Vorinostat mouse forward and reverse primers (5 μM) and 11.5 μl of molecular grade water. Cycling started with an initial denaturation and hot start activation of 10 min at 95°C followed by a low number of 16 cycles of 30 s denaturation at 95°C, 30 s at 50°C and 90 s at 72°C and a final extension of 10 min at 72°C. One μl of each PCR product was then diluted in 99 μl of molecular grade water before the internal stretch was Tucidinostat chemical structure amplified for 454 sequencing. Here, each individual microbiome was tagged by a unique combination of multiplex identifiers (MID, Roche, Basel, CH) integrated into forward and reverse primers [37, 38]. We used a total of 20 tagged primers consisting of the Titanium B sequencing adaptor (Roche, Basel), the 454 sequencing key, a MID tag and the gene-specific sequence. Hence, an example of a forward primer would have the following sequence: 5′-CCATCTCATCCCTGCGTGTCTCCGAC TCAG ACGAGTGCGT CCACGAGCCGCGGTAAT -3′ and a reverse primer: 5′-CCTATCCCCTGTGTGCCTTGGCAGTCTCAG TCAG ACGAGTGCGT CCGTCAATTCMTTTAAGTTT-3′, with the 454 sequencing key in italics, the MID tag in bold and gene specific sequence

underlined. Combinations of forward and reverse MIDs were random with respect to VS-4718 cost treatment and oyster bed. Therefore any amplification bias introduced by the MID will be randomly distributed among groups. After mafosfamide amplification single PCR reactions were purified using the MinElute 96

kit (Qiagen, Hilden) before 2 μl of each elution was used for pooling. To eliminate remaining primer-dimer both pools were purified again using Wizard PCR clean-up system (Promega, Mannheim) following the manufacturer’s instructions. After confirming the sole presence of the desired PCR product without any traces of primer by gel electrophoresis, the pool of individually barcoded PCR reactions were sequenced on the 454 FLX genome sequencer (Roche, Basel, CH) using Titanium chemistry. Sequencing was performed by GATC Biotech (Konstanz, Germany). Data analysis Assignment of reads to individual PCRs was done using modified python scripts from the cogent package. In short, within each raw read we looked for the presence of both primers ensuring complete sequencing of the PCR product. Afterwards, we identified individuals by determining combinations of MID tags allowing for a maximum hemming distance of one in each MID tag. After correct assignment of single reads to an individual oysters, we used the AmpliconNoise pipeline [39] to remove pyrosequencing and PCR noise and Perseus to remove chimeric sequences using default parameters except for alpha and beta values for false discovery detection in Perseus, which were set to −7.5 and 0.5, respectively. Reads were trimmed by cutting off their forward and reverse primers. We used scripts from the Qiime package [40] for the analysis of microbial diversity.

Using cloned pigs in obesity-related studies could provide a more

Using cloned pigs in obesity-related studies could provide a more homogenous experimental model, hence the cloning in this study was performed to minimize genetic influences and thereby reduce inter-individual variation [9]. One of the main focuses of obesity-related gut microbial studies have been to identify groups of bacteria that are correlated with the obese state, and initially the relative abundance of Bacteroidetes and Firmicutes in the gut microbiota was linked to obesity. In pigs, as in humans [10] and other mammals [11], the two main phyla of bacteria in the gut microbiota are Bacteroidetes and

Firmicutes[12, 13]. Previous studies have reported a greater proportion of Firmicutes in obese mice [14] when compared PF-01367338 with their leaner counterparts and a reduced ratio of Firmicutes to Bacteroidetes in a small group of obese humans on a weight loss regimen [15]. A similar result in a study of lean and obese pigs revealed a negative correlation between percentage of Bacteroidetes and body-weight [16]. Furthermore, a fluorescence in situ hybridization

(FISH)-based study on obese adolescents during weight loss regimens showed a decrease in the phylum Firmicutes[17]. However several studies suggest a decrease in ratio of Firmicutes to Bacteroidetes in obese and overweight subjects [18] and suggest diet to be a contributing factor in shaping the gut microbial community and not the bacterial proportions [19, 20]. Other observations in humans, NCT-501 suggest obesity to be associated with a lower bacterial diversity [3], while other studies showed no difference in the abundance of bacteria in the gut microbiota between lean and obese individuals that were on weight maintaining diet [21]. Hence this putative relationship between obesity, diet and specific phyla of bacteria in the gut microbiota is still controversial and there are few studies on the association between the gut microbiota and obesity during the development of obesity. Therefore, the focus of this paper was to investigate the gut microbiota

in cloned pigs compared with non-cloned Clomifene control pigs and to further elucidate if diet-induced obesity over time is associated with changes in the gut microbiota. We hypothesized that the composition of the gut microbiota would be more similar among the cloned pigs compared to non-cloned controls. The second hypothesis was that weight-gain would be related to an increase in the ratio of Firmicutes to Bacteroidetes as well as a decrease in the diversity of the gut microbiota. We therefore investigated the changes in the gut microbiota of cloned and control pigs beginning with lean pigs during a period of 136 days on a high-fat/high-caloric (HF/high-caloric) diet. Methods Animals The animals for this experiment were pigs of similar genotype of Danish AZD1480 Landrace and Yorkshire.

A third cluster of freshwater sequences (2p), entirely composed o

A third cluster of freshwater sequences (2p), entirely composed of sequences sampled from a glacier in Svalbard, belonged to TEL 2. This cluster was distantly related

to the other freshwater group (2e) and was embedded in a large assembly of Arctic and Antarctic sequences, although this relationship was weakly supported (Figure 1). T. subtilis is commonly observed inhabiting the sea-ice in the Baltic Sea [49] and it is therefore possible that these sequences originate from a marine species transported onto the glacier from marine waters by aerosols or other vectors. On the other mTOR inhibitor hand, if these represent an actual freshwater species this would be a second freshwater species within TEL 2, distantly related to the Bayelva River sequences. It remains to be verified that these are actually living cells and whether these have been transported from freshwater sources or dispersed on to the glacier from

marine habitats via aerosols or other vectors. So far, we have not detected sequences from the marine samples that are identical to these glacier phylotypes, which could indicate such freshwater dispersal, but as only few samples have been made in these areas we cannot exclude this possibility. Few marine-freshwater cross-colonizations In Figure 1 the freshwater sequences form Selleckchem LY2874455 distinct selleck inhibitor clusters and phylotypes, suggesting the existence of several different freshwater species. These are placed within both TEL 1 and TEL 2, demonstrating that relatively distantly related species of Telonemia

exists in freshwater. This diversity is detected even with a very limited number of samples; we therefore expect future surveys of other types of freshwaters at other continents to uncover an even larger diversity. The clustering pattern of the Telonemia sequences is in accordance with recent studies of other protist groups showing that freshwater species form distinct clades in phylogenetic trees, i.e. they are more closely related to each other than to marine species [reviewed in [50]]. Such clustering pattern of freshwater phylotypes has in these studies been interpreted as successful marine-freshwater transitions. These transitions have often been ancient and rare events, resulting in most of the extant species being restricted to either of the two habitats: e.g. in bodonids [51], goniomonas [52], cryptomonads [53], dinoflagellates [54] and Perkinsea [55]. If further examinations of freshwater with the use of Telonemia-specific PCR approaches confirms the clustering pattern shown here (see Figure 1), it would imply that the biogeophysical differences between marine and fresh waters constitutes a significant ecological barrier for dispersal of Telonemia that affects diversification of the lineage.

We examined the five genomes of G vaginalis available in the NCB

We examined the five genomes of G. vaginalis available in the NCBI genome database that had spacers targeting coding and non-coding regions on the chromosomes of strains 409–05, 6420B, 315A, 41 V, ATCC14019,

and AMD. We did not find a match between the spacers and the endogenous genomic sequences, except for the sequences located in the CRISPR arrays. We also analysed whether the protospacers located on the G. vaginalis chromosome displayed conserved protospacer adjacent motif (PAM) sequences [41, 42]. We aligned the protospacers with the flanking regions comprising 20 bp on both sides. Alignments were performed for ten AG-120 protospacers sharing 100% identity with the spacers. The conserved motif of two nucleotides (AA) situated immediately upstream of the target region was detected (Figure 5). The PAM signature AA was confirmed for nine protospacers with up to 10% mismatches located distant from the 5′- and 3′-ends of the spacers. Figure 5 WebLogo for the PAM consensus sequence determination. Ten protospacers identical to

spacers were aligned Pexidartinib cost relative to the 5′-end of the protospacer (base 1). Sequences include the protospacer (positive numbers) and 13 nucleotides (negative numbers) upstream of the first base of the protospacer (containing the PAM). Thus, the motifs adjacent to the protospacers located in the G. vaginalis genomic DNA bear the signatures of PAMs. The PLX4032 order orientation of the G. vaginalis PAM is 5′-AA-protospacer-3′, which coincides with the orientation of the PAM identified in E. coli as CRISPR/Cas; both bacteria belong to the same type [41, 42]. Among all of the G. vaginalis CRISPR acetylcholine arrays, the first nucleotide of 97.5% of the spacers was either C or T. Only six spacers started with A or G (2.5%). All of the spacers targeting the protospacers on the G. vaginalis chromosome started with C or T (18:13). Discussion The CRISPR locus of the recently

discovered CRISPR/Cas defence system in prokaryotes protects against invading viruses and plasmids and is a map of the “immunological memory” of the microorganism [25, 26]. The spacer sequences that are incorporated into the CRISPR loci provide a historical view on the exposure of the bacteria to a variety of foreign genetic elements [23]. A recent report on the ability of CRISPR/Cas to prevent natural transformation in Streptococcus pneumoniae enlarged the role of CRISPR in bacterial nucleic acid-based immunity and the impact that CRISPR has on the emergence of bacterial pathogens [43]. In the current study, we analysed the CRISPR arrays in 17 recently characterised G. vaginalis clinical isolates [18] and the genomes of 21 of G. vaginalis strains deposited in the NCBI genome database. We examined the spacer repertoire and evaluated the potential impact of CRISPR/Cas on gene uptake in G. vaginalis. We found that six clinical isolates (35%) and 14 G. vaginalis genomes deposited in the NCBI database (67%) contained CRISPR/Cas loci.

Sublingual testosterone (0 5 mg) produces an increase in sexual m

Sublingual testosterone (0.5 mg) produces an increase in sexual motivation and desire in sexually functional women, about 4 hours after its peak RG-7388 in vitro plasma levels (time to maximum concentration [T max] = 15 min) OSI-906 cell line [9]. The testosterone and the PDE-5 inhibitor are released in such a timeframe that the peak plasma concentration of the PDE-5 inhibitor coincides with the 4-hour delay in behavioral effects of the testosterone. In women with low sensitivity to sexual cues,

this combination showed superiority over placebo in increasing sexual satisfaction [7, 10]. For women who have a dysfunctional activation of sexual inhibitory mechanisms during sexual stimulation, Lybridos is developed. Nirogacestat concentration Lybridos is the combination of sublingual testosterone and a 5-HT1A receptor agonist (buspirone), released in such a timeframe that the pharmacological effects of the 5-HT1A receptor agonist coincide with the behavioral window induced by the testosterone administration

[8]. This combination in women with dysfunctional activation of sexual inhibitory mechanisms increased sexual satisfaction compared with placebo [8]. In previous clinical trials, the two components (sublingual testosterone in combination with a PDE-5 inhibitor or 5-HT1A receptor agonist) were administered separately; however, these components have been developed into one single combination tablet in recent phase IIb trials. Both products are intended for use on a ‘per need’ (i.e., not continuous or chronic) basis before anticipated sexual activity. Studies performed by various researchers have clearly indicated a time lag of about 3–4 hours in the pharmacodynamics effect of sublingual testosterone on genital arousal in women and other cognitive and affective functions [9, 11–23]. Therefore, either the PDE5 inhibitor (Lybrido) or (5-HT1a) receptor agonist (Lybridos) component needs to be administered approximately 2–3 hours after administering the

testosterone. In the above-mentioned clinical studies, this was obtained by administering the testosterone sublingually as a solution, followed 2.5 hours later by a PDE-5 inhibitor (sildenafil) or a 5-HT1A receptor agonist (buspirone) Etofibrate as a tablet (to ensure blinding, the tablet was administered in a gelatin capsule), thus creating overlapping peaks in effect of testosterone and sildenafil or buspirone. Because this kind of administration is not suitable and rather cumbersome for daily use in practice, we developed a single oral combination tablet that will deliver testosterone sublingually and, approximately 2.5 hours later in the gastro-intestinal tract, the sildenafil or buspirone component, allowing women with FSIAD to take just one single tablet 3–6 hours before the anticipated sexual activity. The objective of this study was to see if the pharmacokinetic profile of testosterone given sublingually followed 2.

hominissuis infection PLoS One 2011, 6:e20258 PubMedCrossRef 43

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Biology 2004, 6:145–158. 46. Garbe TR, Barathi J, Barnini S, Zhang Y, Abou-Zeid C, Tang D, Mukherjee R, Young DB: Transformation of mycobacterial species using hygromycin resistance as selectable marker. Microbiology 1994, 140:133–138.PubMedCrossRef 47. Scandurra GM, Young M, de Lisle GW, Collins DM: A bovine macrophage screening system for identifying attenuated transposon mutants of Mycobacterium selleck chemical avium subsp. paratuberculosis with vaccine potential. J Microbiol Methods 2009, 77:58–62.PubMedCrossRef 48. Cavaignac SM, White SJ, De Lisle GW, Collins DM: Construction and screening of Mycobacterium paratuberculosis insertional mutant libraries. Arch

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39 (–9 00)  HVVIT05 (8 19–) 9 39–9 76 (–10 95) (2 00–) 2 29–2 44

39 (–9.00)  HVVIT05 (8.19–) 9.39–9.76 (–10.95) (2.00–) 2.29–2.44 (–2.62) (32.24–) 37.03–42.51 (–49.63) (7.23–) 7.65–8.75 (–9.94) Cryptovalsa rabenhorstii (Nitschke) Sacc., Myc. Ven. 135, tab. XIV. (Fig. 3) Fig. 3 Morphology of Cryptovalsa rabenhorstii. a. Perithecial stroma in the bark of a lignified cane of Vitis vinifera; b. Emerging perithecial ostioles surrounded with white ectostroma and perithecial cavities; c. Long-pedicellate polysporus ascus; d. Mature (light brown) and immature (hyaline) ascospores; e. Colony after 29 days on 85 mm diam PDA dish incubated under intermittent fluorescent lighting

(12 h). Bars = 1 cm in a; 1 mm in b; 50 μm in c–d Basionym: Valsa rabenhorstii Selleck Erastin Nitschke Pyr. Germ. Synonym: Sphaeria spiculosa var. robiniae Rabenh., in Exsicc. Klotzsch, Herb. myc. Stromata in bark of lignified canes (V. vinifera), poorly developed, perithecia buried in the inner bark and scattered in subvalsiform groups of 2–3, or fairly irregularly in larger groups, raising the epidermis which is not discolored and remains attached, or which rupture longitudinally revealing groups of black ostioles occasionally sheltered around a white ectostroma, which apparently facilitate pressuring and splitting of the bark; perithecia outer surface coated with white, powdery entostroma, 0.35–0.55 mm diam, ostioles poorly emerging, more or less distinctly quadrisulcate. Asci long-pedicellate, polysporous,

p. sp. (55−)70−90(−95) × (15−)18−22(−27) μm. Ascospores Resveratrol hyaline VX-689 supplier when immature turning yellowish to light-brown at maturity, sub-allaintoid, AZD0530 chemical structure cylindrical to oblong, (10−)13.5−15(−17.5) × (3.2−)4−5(−6) μm. Colonies white with rather irregular margin. Conidia not seen. Hosts. Vitis vinifera (Australia, WA), Sambuscus nigra (USA,

CA). Notes This species has characteristics typical of members of the genus Cryptovalsa, and resembles closely descriptions of C. rabenhorstii (Nitschke 1867; Saccardo 1882) as well as the illustration by Berlese (1900) of C. ampelina, C. rabenhorstii var. rosarum and C. rabenhorstii var. eutypelloidea. However, as we could not find the type specimen nor obtain culture collections for this species, identification remains tentative. Also, phylogenetic analyses show affinities of this fungus with Eutypella spp. The assignment of this isolate to the genus Cryptovalsa may therefore require future reconsideration. Hence, it is preferable not to propose a novel combination for this species until identification of types and further large scale phylogenetic studies of the Diatrypaceae can be conducted. Specimens examined. AUSTRALIA, WA, Great Southern regions, on lignified canes of Vitis vinifera on the ground, Nov. 2009, F. P. Trouillas, coll. number WA07CO, DAR81041, CBS128338; and coll. number WA08CB, DAR81042, CBS128339. Diatrypella vulgaris Trouillas, W. M. Pitt & Gubler, sp. nov. (Fig. 4) Fig. 4 Morphology of Diatrypella vulgaris. a. Pustulate stromata with white entostroma embedded in the bark of Fraxinus angustifolia; b.

Moreover, none of these resistance genes was detected to lay with

Moreover, none of these resistance genes was detected to lay within the HSs under our analysis conditions, such as the dfrA1 cassette in HS3 in four previously reported ICEs [23, 39]. However, we cannot rule out the possibility of resistance determinants present elsewhere in the ICEs or in host genomes independently of ICE sequences. The former hypothesis seems

more likely, for the successful transmissibility of the antibiotic resistance (Sulr and Stpr) between two Vibrio strains V. cholerae Chn108 and V. parahaemolyticus Chn25 and E. coli MG1655 has been demonstrated Histone Methyltransferase inhibitor by conjugation experiments (see below). The rumB and rumA genes encode a UV repair DNA polymerase and a UV repair protein, respectively [41]. Environmental strains tend to conserve ICEs devoid of antibiotic resistance genes by check details keeping a functional rumBA, compared with clinical strains not exposed to UV but to antibiotics [9]. Moreover, most of the ICE antibiotic resistance genes are found within transposon-like

structures [23]. These may serve as a good explanation as to why typical antibiotic resistance gene clusters were not detected in the VRIII of the ICEs characterized in this study. Exclusion system Entry exclusion systems specifically inhibit redundant conjugative transfers between cells that carry identical or similar elements [42, 43]. SXT and R391 carry genes for an entry exclusion Everolimus price system mediated by two inner membrane proteins, TraG and Eex, which are expressed in the donor and recipient cells, respectively

[44]. Consistent with previous results [10, 43], the ICEs characterized in this study fell into two exclusion groups, S and R (Figure 2). Multiple sequence alignments revealed that the S group elements encode EexS proteins with typical exclusion sequences [45] in their carboxyl termini as known EexS proteins in public databases (data not shown). They also encoded TraGS proteins with exclusion determinant residues P-G-E [43]. In contrast, four elements including ICEVchChn2, ICEVpaChn1, ICEVpaChn3 and ICEValChn1 fell into the R group, which encode the EexR, and TraGR proteins with characteristic exclusion C1GALT1 T-G-D residues (data not shown). It was reported that R391 and pMERPH, belonging to the R exclusion group, contain a DNA insertion conferring resistance to mercury immediately downstream of their respective eexR and eexR4 genes [29, 45]. Unexpectedly, in our study, neither the R nor the S group strains that display strong mercury resistance phenotypes was detected to carry any inserted sequence between the eeX and traG genes under our analysis conditions. The results suggest that the mercury resistance determinants or heavy metal efflux pumps mediating the resistance phenotypes may be present in additional loci in the ICEs, or in their host genomes independently of the ICE sequences. The latter hypothesis seems more likely based on the conjugation experiments.

Schematic representation of ZnO nanorod core coated by PPy sheath

Schematic representation of ZnO nanorod core coated by PPy sheath (A-C) and formation of PPy nanotube array after 2- and 4-h etch (D-E). Top view (F). Growth features of ZnO nanorod-PPy sheath and PPy nanotube

arrays Unlike the two-dimensional flat conducting substrates in which case conventional direct current (dc) potentiostatic electropolymerization of pyrrole can produce uniform thick polypyrrole film, over the semiconducting ZnO nanostructures, pulsed current electropolymerization employed in this work was found essential to obtain homogeneous polypyrrole sheath. In order to create PPy 3-D tubular nanostructures for energy storage action, it is essential (i) to form the PPy sheath in the high-conductivity anion doped state and (ii) to have the PPy sheath of desired thickness coated uniformly over the entire length of the ZnO nanorod array at its core. The first criterion is largely met by anodic electropolymerization of pyrrole monomer in the aqueous medium in the presence of ClO4 learn more 2- anions derived from LiClO4 in the electrolyte. Various mechanisms of pyrrole electropolymerization have been proposed under potentiostatic condition [51, 52]. In the pulsed current electropolymerization

process, the polypyrrole growth over ZnO nanorod surface proceeds by concomitant reactions, anodic oxidation of pyrrole monomer, and conjugation reaction with electrolyte (ClO4 -) anions as shown in Figure 5A. On application of a current pulse of magnitude 4, the pyrrole monomer species over the ZnO nanorod surface rapidly oxidize by electron transfer at electrode resulting in the nucleation of significantly large number of cation radicals. By themselves, these are unstable but stabilize rapidly on interaction with the nearest cation radicals to form short chain oligomers by coupling and bond linkage with the involvement

of deprotonation (-2H+) n+m step [5, 45, 51, 52]. A number of cation radicals at the initiation step are also influenced by strongly interacting electrolyte ClO4 – anions which result in conjugation of PPy short chain oligomers deposited over Staurosporine manufacturer ZnO nanorods [53]. The current pulse off time replenishes the Py-monomers at the ZnO nanorods by diffusion in the aqueous medium. The subsequent pulsed current cycle reinitiates the electropolymerization reaction at fresh nucleation sites on ZnO nanorods by a similar process sequence thus providing a uniform coverage. Figure 5 Electropolymerization process of the polypyrrole growth over ZnO nanorods. (A) Electrochemical polymerization of Py monomer and ClO4 conjugation. (B) Model of electropolymerization growth of PPy sheath over ZnO nanorods in the presence of SDS surfactant and (C) homogenous growth of PPy sheath over ZnO nanorods after a number of pulsed current cycles.