5% This is comparable

5%. This is comparable this website to a study in central Greece assessing 11-year-olds weight status where a total of 30.3% were reported

to be overweight and 6.7% obese [13]. The fact that parental BMI was positively associated with their child’s BMI highlights the importance of family history and environment in the development of obesity. The overweight and obese children in the current study had significantly higher arterial blood pressure, lower HDL-C levels, higher TG and increased insulin compared to their the normal weight counterparts. Higher Tanner scores and heights of the overweight and obese group also suggest earlier onset of puberty, which is often frequently observed in overweight and obese children [14]. GSK2126458 purchase Any interaction between sexual maturity and effects of allelic variation on lipid levels that may have occurred could be accounted for in analyses from the Tanner measures. Genetic factors are considered important determinants of plasma lipid levels in adults, demonstrated in several of the recent genome wide association studies (GWAS) in which a number of candidate genes have been confirmed [15] and [16]. The meta-analysis of 3 GWAS by Willer et al. (2008) identified strong associations with variants in APOA5/A4/C3/A1 cluster, APOE, CETP and LPL influencing plasma lipid concentrations. Although a number

of associations comparable to those seen in adults were confirmed in this study, the role of genetic factors in the heterogeneity of plasma lipid levels in children is less clear. Replication of these variants in cohorts of children is needed. In GENDAI, APOE genotypes were associated with differences in TC and LDL-C plasma levels and the TC: HDL-C ratio. The LDL-C and TC lowering

effect of the ɛ2 allele reported in the recent meta-analysis [17] was also observed in this cohort of young Greek children. Carriers of the ɛ4 allele had LDL-C and TC levels that were 19.9% and 12.2% higher than carriers of the ɛ2 allele and 2.8% and 1.3% higher than ɛ3/ɛ3 subjects. The results of a 21-year longitudinal study on changes in serum lipids in 1233 Finns followed from childhood to adulthood AZD9291 datasheet consistently observed the ɛ2 allele to be associated with lower LDL-C levels and the ɛ4 allele with higher TC and LDL-C levels (p < 0.001 for all associations) in childhood. The LDL-C-lowering effect of the ɛ2 allele was an association that was tracked through to adulthood, having a greater effect with increasing age (p = 0.039). The association of the APOE genotype with plasma TC and LDL-C has been reported in children as young as 3 years old [18]. The fact that differences in lipid levels cannot be detected in children at birth by the APOE genotype leads to the conclusion that lipid levels are influenced by genetic and environmental factors in a child’s very first years of life [18].

So to summarize,

So to summarize, selleck chemicals to which extent EVs contain truly distinct types of vesicles requires further investigation, and at present no tools are available to purify a single type or population of vesicle based on size or density.3 EVs expose tissue/cell type-specific marker proteins of their parent cell.[3], [4] and [44] When a sufficient number of such marker proteins are exposed, the cellular origin of a vesicle can be determined

by e.g. flow cytometry using antibodies directed against such marker proteins. This is illustrated in Table 2, in which a shortlist of commonly used marker proteins is summarized for analysis of vesicles in human blood (CD: cluster of differentiation). The numbers, cellular origin, composition and functional properties of EVs are not only disease (state) dependent, but also depend on the body fluids being studied. The major populations of EVs in a body fluid usually reflect the cells that are present in that particular body fluid and that surround the body fluid. Examples of the latter are vesicles from synoviocytes which are present in joint (synovial) fluid, and vesicles from endothelial cells (ECs) in blood. We will briefly summarize the cellular origin presence of EVs in blood, urine, saliva, cerebrospinal and synovial fluids in the following paragraphs. In peripheral blood of a healthy subject, platelets and erythrocytes

are the major sources of EVs, but in certain disease states such as sepsis, cardiovascular disease (CVD), or cancer, also MVs from monocytes, granulocytes, lymphocytes, ECs, and cancer cells can be present.45 Peripheral blood also contains exosomes,46 although the cellular Ku-0059436 order origin of these vesicles is unknown. Urine of healthy humans and amniotic fluid both

contain significant numbers of exosomes or exosome-like vesicles.47 These exosomes expose CD24 and aquaporin-2, therefore, are likely to originate from kidney cells48 and from epithelial cells tetracosactide facing the renal tubule lumen.49 Urine contains also larger vesicles, but thus far the characterization of these two types of vesicles in urine has been problematic.50 In saliva from healthy individuals, the larger vesicles, MVs, are derived mainly from epithelial cells and granulocytes, whereas the smaller vesicles, i.e. exosomes or vesicles resembling exosomes, are mainly from epithelial cell origin.51 Cerebrospinal fluid also contains EVs.52 In vitro, various types of brain cells such as astrocytes, microglia, oligodendrocytes and neurons release exosomes.53 The source of the EVs in cerebrospinal fluid, however, is presently unknown. Synovial fluid of rheumatoid arthritis (RA) patients and patients with other types of arthritis contain MVs.[18] and [54] Most of these MVs originate from cells associated with inflammation, such as monocytes and granulocytes. In addition, synovial fluid also contains vesicles from synovial fibroblasts.55 Taken together, every body fluid has a clearly distinct vesicle profile.

19) in the evaluation period The most likely source for this bia

19) in the evaluation period. The most likely source for this bias is that the precipitation inputs are already biased. From the calibration to the evaluation periods mean annual precipitation Smad2 phosphorylation increased by +3%, but observed discharge decreased by −4%. Even though these are small changes, it is counter-intuitive that discharge decreases when

precipitation increases. Here, the low density of precipitation stations has to be considered in the upper Zambezi basin, which is on average approximately one station per 21,000 km2 in the calibration period, but even lower during the evaluation period (see Fig. 2). An under-estimation of discharge in the evaluation period is also obtained at the upstream gauge Lukulu, albeit the period with available data is only 7 years. The under-estimation of Kafue River discharge at the gauge Kafue Hook Bridge during the calibration period is the result of a large negative bias (−34%) during a 5-year period (1978–1982), which coincides with the start of operation of nearby Itezhitezhi reservoir. The source of this bias is not clear, but it could be related to the accuracy of the precipitation data or the discharge data. Outside this 5-year period the simulation shows only a small bias – this also applies to the independent evaluation period. The calibrated model was applied for simulation of a number of pre-defined scenarios (see Table 3). The scenario

simulations are always compared Phosphoribosylglycinamide formyltransferase against the “Baseline” scenario representing current Selleckchem BKM120 water resources management (reservoirs, operation rules, irrigation withdrawals) in the basin but using historic climate of the period 1961–1990. The analysis focuses on Zambezi River discharge at Tete in Mozambique. Table 5 lists mean annual scenario results. Mean annual discharge in the Baseline scenario amounts to approximately 2600 m3/s, with values ranging from around 1750 m3/s to

3700 m3/s in the scenario simulations. Total evaporation losses from reservoirs amount to 437 m3/s in the Baseline scenario. This value ranges from 418 to 499 m3/s in the other scenarios. The differences are caused by: • Different number of reservoirs (Batoka Gorge and Mphanda Nkuwa are included in the Moderate and High development scenarios). More than 90% of the total reservoir evaporation occurs from Kariba and Cahora Bassa reservoirs. These are significant losses of water and the main reason that under the Pristine scenario (with no reservoirs) discharge is considerably larger than in the other scenarios. In addition to the reservoirs, water also evaporates from the natural wetlands and floodplains – with mean annual evaporation losses ranging from 243 to 364 m3/s between the scenarios. The contribution to total evaporation from the individual wetlands is roughly 40% from Kafue Flats, 25% from Barotse Floodplain, 25% from Chobe Swamps, and 10% from Kwando Floodplain.

In general, iterative methods would be necessary [20] and faster

In general, iterative methods would be necessary [20] and faster methods [40] have been developed to speed up the reconstruction process. Only a single transverse slice was imaged in the phantom, which was unaffected by eddy-current components that vary in the z-direction. However, it is expected that correction would work well for all orientations since the eddy-current phases were measured in three dimensions on a sphere. With the NMR probes located at a fixed radius on a sphere, the volume over which the correction can be performed can be extended

outside the radius of the field camera unless NVP-BKM120 solubility dmso there are spatial non-linearities in the gradients. The non-uniformity of the field produced by gradient coils was not taken into account for the determination of the probe locations. Gradients were assumed to be linear within the 20 cm diameter of the field camera. Oscillations were seen in some phase coefficients, particularly the y gradient, which could be due to mechanical resonances [34] and [41] CYC202 manufacturer or possibly related to the EPI

readout [20]. Mechanical vibrations could be the cause of the residual signal variation between different diffusion-encoding directions seen in Fig. 4. Another possible cause for this signal variation could be the eddy currents from the first diffusion lobe affecting the 180° refocusing pulse. Incomplete refocusing can result in non-linear effects across the image, which would be different for each diffusion-encoding direction. Correcting for incomplete refocusing would require measurement of eddy-current phases during the refocusing pulse, as well as subsequent correction of unwanted phase contributions in the slice-refocusing gradients for every diffusion-encoding PAK6 direction. The addition of parallel

imaging can be used to reduce the readout train length and hence the level of distortions. However, in this study, the temporal eddy-current phases showed accumulation early in the readout, suggesting that eddy-current correction may offer improvements even for the short readouts enabled by parallel imaging. Reducing the FOV by the use of orthogonal excitation and refocusing pulses is an alternative approach for reducing distortion levels. Similar distortion levels can be maintained, for example, by using a parallel-imaging reduction factor of two with a doubled FOV and the same readout length. Although parallel imaging enables larger FOVs without increasing the level of distortions, the reduced-FOV method (by orthogonal excitation pulses) remains useful for imaging smaller FOVs where parallel imaging can be less effective due to the lack of coil-sensitivity variation over these smaller FOVs. In this study, the reduced-FOV method was used to effectively minimize the readout length, and hence, the level of distortions before eddy-current correction.

Samples were placed on ice in the field, then later frozen In th

Samples were placed on ice in the field, then later frozen. In the laboratory, mussels were measured for shell total length, thawed and dissected. Adductor muscle tissue was dissected from individual animals, rinsed in deionized water (DI), and dried at 60 °C. The outermost

10 mm of mussel shells that represented the most recent growth was broken off and treated with bleach to remove Epacadostat datasheet organic matter. Shells were soaked overnight in household bleach (Chlorox, 6% sodium hypochlorite) to remove soft tissues, crushed into coarse fragments and soaked again overnight with bleach, then rinsed extensively with DI prior to drying at 60 °C. Barnacles were thawed, basal diameters were measured, and for each station approximately 50–100 animals with basal diameters of 5–20 mm were separated from their shells and combined into a composite site sample. Soft tissues were placed briefly in 1 N HCl and any carbonate shell detected by

bubble evolution was removed under a dissecting microscope. Cleaned soft tissues were then rinsed with deionized water and dried at 60 °C. Barnacle shells were treated with bleach as described above for mussels. Barnacle soft tissues MK0683 mouse were pulverized with a steel rod in glass vials. All other samples including shells and tissues of mussels were pulverized with a Wig-L-Bug automated grinder (Dentsply International). Shells and tissues were analyzed for δ13C by standard combustion methods with isotope ratio mass spectrometry (Fry, 2007), and results are reported as δ13C values using the VPDB reference (Coplen, 1994) where δ13C = (RSAMPLE/RSTANDARD − 1) * 1000 and R = 13C/12C. Samples for radiocarbon analyses were sent to the Rafter Radiocarbon Laboratory in Lower Hutt, New Zealand for measurement with accelerator mass spectrometry; results are reported as Δ14C values ( Stuiver and eltoprazine Polach, 1977). For

δ13C, both diet and inorganic carbon dynamics have been shown to affect filter feeder isotope values (Fry, 2002), with the inorganic carbon dynamics at the base of food webs leading to higher δ13C values for plants and animals in more marine portions of estuaries. To account for this basal or baseline effect which is conveniently recorded by inorganic carbon in shell carbonate, the fractionation between shells and filter feeder tissues was calculated as 13ε=(RSHELL/RTISSUE-1)*100013ε=(RSHELL/RTISSUE-1)*1000where R is the 13C/12C isotope ratio in the δ13C definition. The 13ɛ values can be thought of as the baseline-corrected fractionation through the food web leading to filter feeders, and can be compared to the fractionation expected for dietary reliance on 100% non-oil normal estuarine foods versus fractionation expected from a 100% oil-based diet.

e , centered at sufficiently high |B1+|), the process can start w

e., centered at sufficiently high |B1+|), the process can start with a conventional single-band linear-phase

finite impulse response filter designed using a weighted-least squares method. That filter is then duplicated, and the duplicates are frequency modulated selleck chemicals llc to opposite center frequencies and subtracted from each other. This is equivalent to modulation of the single-band filter by a sine function at the center frequency. For very close passbands (i.e., passbands close to |B1+|=0) however, ripples from one band can distort the other. In these cases, an odd, dual-band ββ filter can be designed directly using weighted-least-squares. The distortions could also be mitigated using a phase-correction method [20]. Once the ββ filter is designed, assuming small excitation angles the inverse SLR transform reduces to a simple scaling of the filter coefficients to obtain the ΔωRF(t)ΔωRF(t) waveform. The SLR algorithm conventionally designs an RF pulse that accompanies a constant gradient waveform. In |B1+|-selective selleck compound pulse design, A(t)A(t) replaces the gradient waveform. In the small-excitation angle regime, the αα profile at the end of a pulse with duration T   is [18]: equation(6) α(|B1+|)=e-ıγ2|B1+|∫0TA(t)dt,and the ββ profile is: equation(7) β(|B1+|)=ı2eıγ2|B1+|∫0TA(s)ds∫0TΔωRF(t)e-ıγ|B1+|∫tTA(s)dsdt.

equation(8) =ı2eı2|B1+|k(0)∫0TΔωRF(t)e-ı|B1+|k(t)dt,where k(t)≜γ∫tTA(s)ds is the pulse’s |B1+|-frequency trajectory. From Eq. (6), it is evident that if A(t)A(t) is constant and comprises no pre- or rewinder lobes before or after the ΔωRF(t)ΔωRF(t) waveform to achieve zero total area, then αI≠0, which is unacceptable. Zero total area could be achieved by adding a negative rewinder lobe to A(t)A(t) with the same area as the main lobe, but according to Eq. (8) this would create a nonzero βIβI since ΔωRF(t)ΔωRF(t) would deposit energy at negative frequencies only, as depicted in the middle column of Fig. 3. A real and odd ββ profile can only be produced if ΔωRF(t)ΔωRF(t) deposits energy anti-symmetrically

as a function of frequency, and therefore cannot be produced with this trajectory. Placing the rewinder lobe at the beginning of the pulse would also lead to nonzero βIβI. The desired symmetric k(t)k(t) can be restored Thiamet G by splitting the rewinder lobe, so that half is played at the beginning and half at the end, as shown in the right column of Fig. 3. With this configuration, α=1α=1 and βI=0βI=0 as required. This A(t)A(t) waveform configuration is analogous to a balanced gradient waveform configuration for conventional slice-selective excitation, which is commonly used for refocusing pulses in spin echo sequences and for excitation pulses in balanced steady-state free precession sequences [21]. Fig. 4a shows that as a |B1+|-selective pulse is scaled to excite a large tip-angle, αIαI grows and degrades the excited profile by creating a large unwanted MyMy component (Eq. (4)), particularly in the stopband.

AhpC is an enzyme that converts various alkyl hydroperoxides to t

AhpC is an enzyme that converts various alkyl hydroperoxides to their corresponding alcohols, and can change hydrogen peroxide to water. This enzyme contributes AZD2281 datasheet to microorganism survival in host conditions via the protection of the cells from oxidative stress [42]. During our investigation to

determine the complete genome sequence of a human clinical isolate (PAGU 611) from the blood sample of a cellulitis subject, we revealed that the microorganism holds a Type VI secretion system (T6SS) which is thought to be related to its virulence [43]. T6SS is a kind of complex multi-component secretion machine, often called a “needle” or “molecular syringe”. In many cases, T6SS delivers bacteriolytic Navitoclax clinical trial effectors to target cells, such as other bacteria or eukaryotic hosts, and in some cases is involved in symbiotic interactions with eukaryotic hosts [44] and [45]. In the case of Helicobacter hepaticus, another enterohepatic species that is harbored in mouse intestines, T6SS was reported to play an important role in persistent colonization to promote a balanced relationship with the host via the T6SS directed anti-inflammatory gene expression profiles in intestinal epithelial cells and CD4+ T cells [46]. Another report described an association between VgrG1, a secreted protein of T6SS, and bacterial colitogenic potential [47]. The role of the T6SS in H. cinaedi infection Carnitine dehydrogenase is not clear; however,

there might be a similar virulence function. The PAGU 611 chromosome encodes two known virulence factors, described above, cdt and ahpC genes, and also several putative virulence-related proteins, such as fibronectin- and fibrinogen-binding proteins, neutrophil activation protein, and Campylobacter jejuni invasion antigen B [43]. The type strain of H. cinaedi, another complete genome determined strain [48], has all of the above-mentioned

(putative) virulence factors; thus, these factors might be commonly harbored within the human isolates. Further investigation is needed to clarify the virulence of this microorganism. It is well known that H. cinaedi is a fastidious and slow-growing organism and that detection and cultivation are extremely difficult. In this section, methods of detection, culture, and identification are described, as well as the description of new taxon for the genus Helicobacter. Isolates of H. cinaedi are mainly obtained from blood and, to a lesser extent, fecal samples. In fact, H. cinaedi is in many cases first detected from blood culture using an automatic blood culture system. Nowadays, many hospital laboratories employ an automatic blood culture system, such as the BACTEC or BacT/ALERT systems. Recently, another blood culture system, VersaTREK, has been introduced in Japan. Because H. cinaedi are slow-growing organisms, a relatively prolonged incubation time is generally required.

However, for a distinct method

and its detection range, t

However, for a distinct method

and its detection range, the required enzyme amount can be estimated. This will be demonstrated with the example of the UV/visible spectroscopy. The authentic absorption range is between 0 and 1, while for higher absorptions the Lambert–Beer law is no longer valid. To determine the initial velocity of an enzyme reaction, e.g. of a dehydrogenase, an absorption range of 0.1 is sufficient, and higher absorptions will easily exceed the linear phase of the progress curve. So an enzyme amount producing an absorption difference of 0.1/min will be convenient. The absorption coefficient of NADH at 340 is 6300 M−1 cm−1, 1 µmol NADH per ml has an absorption of 6.3; 0.016 µmol NADH/ml show an absorption of 0.1. To convert 0.016 µmol NADH/min in 1 ml assay mixture 0.016 IU Ibrutinib supplier respectively 0.27 nkat enzyme are required. Due to the divergent features of enzymes a general standardization of enzyme assays is not possible, rather special rules can be given as follows: 1. pH: Preferentially

the pH of the pH optimum of the respective enzyme is chosen, as far as possible at or near the physiological pH (~7.5). The author has no conflict of interest. “
“Developing sensitive enzyme assays suitable for high-throughput screening (HTS) requires identification of relevant enzyme and substrates forms, methods in purification, careful measurements of kinetic parameters, characterization of co-factors, buffers, and choice of a detection technology for the final HTS assay. find more The desired mode of action (e.g. allosteric, competitive, slow-binding ADAM7 inhibitors) for active compounds should also be considered in the assay development process. In the first part of this review we define the goals of an HTS

enzyme assay and provide an overview of the key steps in this process. In the second part we give an overview of specific technologies that have been employed to measure activity for various enzyme classes in a high-throughput setting. As well, we discuss the critical parameters that should be conveyed when reporting HTS enzyme assay data. In general, cell-free HTS assays for enzymes have been developed using three main approaches (Figure 1). These are (1) detection of substrate depletion, (2) detection of product formation and (3) detecting direct binding of a ligand to the enzyme. Methods for measuring the E·S complex, although available for many years using fast kinetic readers (Lobb and Auld, 1979), have not transitioned into HTS. For some well-explored enzyme families such as protein kinases all three methods are available and the choice of which assay to use will depend on biases towards a particular detection technology, reagent expense, the amount of enzyme required and ease of implementation within the laboratory. These considerations are discussed below along with the goals of HTS enzyme assays.

, 2004) For a variety of animal species and for different modali

, 2004). For a variety of animal species and for different modalities it has been demonstrated selleck chemicals llc that single neurons respond in a temporally sparse manner (Reinagel, 2001, Jadhav et al., 2009, Olshausen et al., 2004 and Hromádka et al., 2008) when stimulated

with natural time-varying input. In the mammal this is intensely studied in the visual (Dan et al., 1996, Vinje and Gallant, 2000, Reinagel and Reid, 2002, Yen et al., 2007, Maldonado et al., 2008, Haider et al., 2010 and Martin and Schröder, 2013) and the auditory (Hromádka et al., 2008, Chen et al., 2012 and Carlson et al., 2012) pathway as well as in the rodent whisker system (Jadhav et al., 2009 and Wolfe et al., 2010). Sparseness increases across sensory

processing levels and is particularly high in the neocortex. Individual neurons emit only a few spikes positioned at specific instances during the presentation of a time-varying input. Repeated identical stimulations yield a high reliability and temporal precision of responses (Herikstad et al., 2011 and Haider et al., 2010). Thus, single PARP inhibitor neurons focus only on a highly specific spatio-temporal feature from a complex input scenario. Theoretical studies addressing the efficient coding of natural images in the mammalian visual system have been very successful. In a ground breaking study, Olshausen et al. (1996) learned a dictionary of features for reconstructing a large set of natural still images under Nintedanib (BIBF 1120) the constraint of a sparse code to obtain receptive fields (RFs), which closely resembled the physiologically measured RFs of simple cells in the mammalian visual

cortex. This approach was later extended to the temporal domain by van Hateren and Ruderman (1998), learning rich spatio-temporal receptive fields directly from movie patches. In recent years, it has been shown that a number of unsupervised learning algorithms, including the denoising Autoencoder (dAE) (Vincent et al., 2010) and the Restricted Boltzmann Machine (RBM) (Hinton and Salakhutdinov, 2006, Hinton et al., 2012 and Mohamed et al., 2011), are able to learn structure from natural stimuli and that the types of structure learnt can again be related to cortical RFs as measured in the mammalian brain (Saxe et al., 2011, Lee et al., 2008 and Lee et al., 2009). Considering that sensory experience is per se dynamic and under the constraint of a temporally sparse stimulus representation at the level of single neurons, how could the static RF model, i.e. the learned spatial feature, extend into the time domain? Here we address this question with an unsupervised learning approach using RBMs as a model class.

After these experimental analyses, all lactones compounds were su

After these experimental analyses, all lactones compounds were submitted to ab initio quantum calculations (DFT – Density Functional Theory – UB3LYP/6-31G*) and the values

of their physical–chemistry properties were analyzed by chemometric methods, in order to recognize patterns that correlate the lactone structures with their biological activities. The results obtained may aid in the development of new selective inhibitors for phospholipases A2 and, consequently, Selleck PD 332991 the treatment of poisoning by snake bites. All reagents, including Lac01 (α-santonin), were purchased from Aldrich or Sigma Co (USA). B. jararacussu venom was purchased from a private serpentarium in Formiga, MG, Brazil. B. jararacussu PLA2 was isolated employing two chromatographic steps: first gel filtration on Sephadex G-75, followed by cation-exchange chromatography. The column was previously equilibrated with 0.05 M ammonium bicarbonate buffer, pH 8.0. Elution was carried out with a continuous gradient up to a concentration

of 0.5 M ammonium bicarbonate. Absorbance of the effluent solution was recorded at a wavelength of 280 nm. PLA2 homogeneity was assessed by native and SDS-PAGE and reverse-phase selleckchem HPLC. Fraction II, known as Asp49 BthTX-II, was used in this study. This phospholipase will be denominated in this paper as just PLA2 ( Da Silva et al., 2008a and Da Silva et al., 2008b). Male Swiss mice, 6–8

weeks old, were matched for body weight (18–22 g). The animals were housed for at least one week before the experiment in laminar-flow cages maintained at a temperature of 22 ± 2 °C and a relative humidity of 50–60%, under a 12:12 h light–dark cycle. The animal experiments were carried out with the approval of the institutional committee of ethics, in accordance with protocols following the recommendations of the Canadian Council on Animal Care. The mice used in this study Cytidine deaminase were kept under specific pathogen-free conditions. The compounds employed in this study are shown in Fig. 1. Lactones 2, 3, 5, 6, 7, and 8 were prepared by procedures described in the literature (Arantes et al., 2009 and De Alvarenga et al., 2009). Lac04 was prepared as described below. To characterization of Lac04: IR spectra were recorded on a Perkin Elmer Paragon 1000 FTIR spectrophotometer, KBr, νmax, cm−1. 1H and 13C NMR spectra were obtained on a Bruker AVANCE DRX400 spectrometer at 400 and 100 MHz, respectively, and a Varian Mercury spectrometer observing 1H at 300 MHz and 13C at 75 MHz. All 1H and 13C spectra were obtained using CDCl3 as solvent and TMS as internal standard. Low resolution mass spectra were obtained on a SHIMADZU GC MS-QP5050A instrument by direct injection. The microanalysis was obtained on a PERKIN ELMER 2400 instrument.