YphC and YsxC GTPases assist the maturation of the central protuberance,GTPase associated region and functional core of the 50S ribosomal subunit

YphC and YsxC are GTPases in Bacillus subtilis that facilitate the assembly of the 50S ribosomal subunit, however their roles in this process are still uncharacterized. To explore their function, we used strains in which the only copy of the yphC or ysxC genes were under the control of an inducible promoter. Under depletion conditions, they accumulated incomplete ribosomal subunits that we named 45S_YphC and 44.5S_YsxC particles. Quantitative mass spectrometry analysis and the 5–6 Å resolution cryo-EM maps of the 45S_YphC and 44.5S_YsxC particles revealed that the two GTPases participate in the maturation of the central protuberance, GTPase associated region and key RNA helices in the A, P and E functional sites of the 50S subunit. We observed that YphC and YsxC bind specifically to the two immature particles, suggesting that they represent either on-pathway intermediates or that their structure has not significantly diverged from that of the actual substrate. These results describe the nature of these immature particles, a widely used tool to study the assembly process of the ribosome. They also provide the first insights into the function of YphC and YsxC in 50S subunit assembly and are consistent with this process occurring through multiple parallel pathways, as it has been described for the 30S subunit.     

Effects of carbon source and concentration on development of lingonberry (<Emphasis Type="Italic">Vaccinium vitis-idaea</Emphasis> L.) shoots cultivated <Emphasis Type="Italic">in vitro</Emphasis> from nodal explants

Summary Carbohydrate type and concentration and their interactive effects on in vitro shoot proliferation of three lingonberry (Vaccinium vitis-idaea ssp. vitis-idaea L.) cultivars (‘Regal’, ‘Splendor’, and ‘Erntedank’) and two V. vitis-idaea ssp. minus (Lodd) clones (‘NL1’ and ‘NL2’) were studied. Nodal explants were grown in vitro on medium with 2 μM zeatin and either glucose, sorbitol, or sucrose at a concentration of 0, 10, 20, or 30 gl⁻¹. The interactive effects of carbohydrate type and concentration and genotype were important for shoot proliferation. The best response was afforded by sucrose at 20 gl⁻¹ both in terms of explant response and shoot developing potential, although glucose supported shoot growth equally well, and in ‘NL1’ at 10 gl⁻¹ it resulted in better in vitro growth than sucrose. Carbohydrate concentration had little effect on shoot vigor. The genotypes differed in terms of shoots per explant, length, and vigor, leaves per shoot, and callus formation at the base of explants; this was manifested with various types and concentrations of carbohydrate. Changing the positioning of explants on the medium from vertically upright to horizontal increased the shoot and callus size, but decreased shoot height and leaves per shoot. Proliferated shoots were rooted on a peat:perlite (1∶1, v/v) medium and the plantlets were acclimatized and eventually established in the greenhouse.     

Assessment of atrial regional and global electromechanical function by tissue velocity echocardiography: a feasibility study on healthy individuals

Background

Myocardial contrast echocardiography and coronary flow velocity pattern with a rapid diastolic deceleration time after percutaneous coronary intervention has been reported to be useful in assessing microvascular damage in patients with acute myocardial infarction.

Aim

To evaluate myocardial contrast echocardiography with harmonic power Doppler imaging, coronary flow velocity reserve and coronary artery flow pattern in predicting functional recovery by using transthoracic echocardiography.

Methods

Thirty patients with anterior acute myocardial infarction underwent myocardial contrast echocardiography at rest and during hyperemia and were quantitatively analyzed by the peak color pixel intensity ratio of the risk area to the control area (PIR). Coronary flow pattern was measured using transthoracic echocardiography in the distal portion of left anterior descending artery within 24 hours after recanalization and we assessed deceleration time of diastolic flow velocity. Coronary flow velocity reserve was calculated two weeks after acute myocardial infarction. Left ventricular end-diastolic volumes and ejection fraction by angiography were computed.

Results

Pts were divided into 2 groups according to the deceleration time of coronary artery flow pattern (Group A; 20 pts with deceleration time ≧ 600 msec, Group B; 10 pts with deceleration time < 600 msec). In acute phase, there were no significant differences in left ventricular end-diastolic volume and ejection fraction (Left ventricular end-diastolic volume 112 ± 33 vs. 146 ± 38 ml, ejection fraction 50 ± 7 vs. 45 ± 9 %; group A vs. B). However, left ventricular end-diastolic volume in Group B was significantly larger than that in Group A (192 ± 39 vs. 114 ± 30 ml, p < 0.01), and ejection fraction in Group B was significantly lower than that in Group A (39 ± 9 vs. 52 ± 7%, p < 0.01) at 6 months. PIR and coronary flow velocity reserve of Group A were higher than Group B (PIR, at rest: 0.668 ± 0.178 vs. 0.248 ± 0.015, p < 0.0001: during hyperemia 0.725 ± 0.194 vs. 0.295 ± 0.107, p < 0.0001; coronary flow velocity reserve, 2.60 ± 0.80 vs. 1.31 ± 0.29, p = 0.0002, respectively).

Conclusion

The preserved microvasculature detecting by myocardial contrast echocardiography and coronary flow velocity reserve is related to functional recovery after acute myocardial infarction.     

The VNTR polymorphism in the human dopamine transporter gene: improved detection and absence of association of VNTR alleles with attention-deficit hyperactivity disorder

The human dopamine transporter (DAT1) gene contains a variable number tandem repeat (VNTR) in its 3'-untranslated region because of repetition of a 40-bp core sequence. Methods available for the diagnosis of this polymorphism are limited in number. We have developed a new polymerase chain reaction (PCR) test, which is similar to that described originally by Vandenbergh's group, but provides a better detection of the VNTR alleles in the human DAT1 gene. Using two independent PCR methods, we have determined the distribution of VNTR alleles in 110 healthy Omani subjects, and in 92 children with attention-deficit hyperactivity disorder (ADHD). The frequency of the risk allele (DAT1*10) was similar in the healthy subjects and ADHD cases, indicating absence of association of this allele with ADHD in Oman.     

Conception rates of dairy cows following early not-pregnant diagnosis by ultrasonography and subsequent treatments with shortened Ovsynch protocol

Our objective was to determine the feasibility of prompt reinsemination of dairy cows when diagnosed not pregnant 27-29 days after first-service timed AI (TAI). We assumed that a first-wave dominant follicle was present at that time that would ovulate in response to GnRH once precocious luteal regression was induced after administration of PGF(2alpha). Cows that had not been detected in estrus and reinseminated by Days 27-29 after a first-service TAI were diagnosed not pregnant by ultrasonography. Nonpregnant cows from three herds were assigned randomly to receive either no further treatment until reinsemination (controls; n=189); 25mg i.m. of PGF(2alpha) and then reinsemination according to detected estrus (81 of 108) or at 72-80h after PGF(2alpha) treatment (PGF) in the absence of estrus (27 of 108); or 25mg i.m. of PGF(2alpha) followed by 100 microg i.m. of GnRH 48h later (PGF+GnRH) and then reinsemination after detection of estrus (9 of 160) or at 16-20h after GnRH (151 of 160). Blood samples were collected at the time of the not-pregnant diagnosis and again 48h later. Concentrations of progesterone before treatment with PGF(2alpha) were elevated (<1ng/ml) in 61% of the cows when PGF(2alpha) was administered and 81% of the cows given PGF(2alpha) had low (<1ng/ml) concentrations of progesterone 48h after PGF(2alpha). Treated cows were re-inseminated earlier (P<0.01; 31+/-1days) after first-service TAI than controls (55+/-1days). Conception rates after treatment were not different among treatments: PGF (22%), PGF+GnRH (23%), and control (23%). Average intervals from calving to conception were 22-23 days less (P<0.001) in treated cows than in controls. We concluded that treating nonpregnant cows with PGF(2alpha) on Days 27-29 after insemination produced acceptable conception rates when inseminations were made after detected estrus or when TAI was used after GnRH treatment. Further, both treatments reduced days between first-service TAI and second inseminations, and days from calving to conception.     

Production of D-tagatose, a low caloric sweetener during milk fermentation using L-arabinose isomerase

Lactobacillusdelbrueckii subsp. bulgaricus and Streptococcus thermophilus are used for the biotransformation of milk in yoghurt. During milk fermentation, these lactic acid bacteria (LAB) hydrolyze lactose producing a glucose moiety that is further metabolized and a galactose moiety that they are enable to metabolize. We investigated the ability of L. bulgaricus and S. thermophilus strains expressing a heterologous L-arabinose isomerase to convert residual D-galactose to D-tagatose. The Bacillus stearothermophilus US100l-arabinose isomerase (US100l-AI) was expressed in both LAB, using a new shuttle vector where the araA US100 gene is under the control of the strong and constitutive promoter of the L. bulgaricus ATCC 11842 hlbA gene. The production of L-AI by these LAB allowed the bioconversion of D-galactose to D-tagatose during fermentation in laboratory media and milk. We also established that the addition of L-AI to milk also allowed the conversion of D-galactose into D-tagatose during the fermentation process.     

Toxicological Aspect of Some Selected Medicinal Plant Samples Collected from Djelfa,Algeria Region

Biological Trace Element Research - Instrumental neutron activation analysis (INAA) has been used to determine the concentration of some toxic chemical elements in a variety of aromatic plants...     

Hydrocarbon bioremediation potential of an unimpacted Kuwaiti oil-field environment

Seasonal variations in the hydrocarbon-degrading potential of soil samples from an unimpacted site in the Kuwaiti Burgan oil field environment were studied under mesophilic conditions. Hydrocarbon-degrading microorganisms occurred but varied all-year-round, and their numbers ranged from 1.3 x 10(7) to 9.3 x 10(7) CFU g(-1) dry soil, while hydrocarbon-degrading fungi ranged from 3.0 x 10(4) - 3.8 x 10(5) CFU g(-1) dry soil, depending on the sampling period. These hydrocarbon-degraders also comprised variable but generally high proportions of the total aerobic heterotrophic organisms (2 to > 98%) for bacteria and lower levels (7-9%) for fungi. The crude oil-degrading capacity of the oil-degrading populations (bacteria and fungi) ranged from 80-95% of the hexane-extractable fractions. Differential inhibition studies carried out on soil samples showed that bacteria were the greater contributors to hydrocarbon degradation (79-92%) than fungi. Pure hydrocarbon substrates, hexadecane and phenanthrene, were degraded to near completion after a 28-day incubation by both the bacterial and fungal portions of the soil flora.     

Activation of transposable elements and insertional polymorphism in Opuntia offspring as assessed by inter-retrotransposon amplified polymorphism markers

Activation of retrotransposon is a pivotal factor in the genesis of genetic polymorphism. Retrotransposon-based molecular markers are excellent tools for detecting genetic diversity and genomic changes associated with their activity. The objective of this study was to use IRAP markers to detect integration events of retrotransposon in Opuntia, and to compare IRAP and ISSR polymorphisms. To achieve these aims, five IRAP and five ISSR markers were analyzed on three varieties and their progenies. All IRAP primers showed an increase in the percentage of polymorphism, number of total bands, and polymorphic bands in the seedlings compared to their mother plants; that is, the offspring showed 13, 24 and 27 more bands than the mother plants from Tobarito, Montesa and Copena varieties, respectively. Conversely, sexual reproduction did not proportionally affect the variation in the number of ISSR bands, and neither did polymorphisms between mother plants and their offspring. Cluster and multivariate analyses based on IRAP and ISSR data revealed a clear separation between varieties, and there was no overlapping between seedlings of different varieties. The activation of retrotransposons in seedlings of opuntia with variable frequencies was evidenced. The presence of insertion and active retrotransposons may help to undertake studies on genetic diversity and evolution of Opuntia.     

Optimization of the Water-Insoluble Procedures for <Emphasis Type="Italic">USP</Emphasis> General Chapter <Emphasis Type="Italic">Residual Solvents</Emphasis> <467>

The water-insoluble procedures in US Pharmacopeia (USP) General Chapter Residual Solvents <467>, which are based on European Pharmacopoeia procedures, were optimized and modified before their inclusion in the chapter to improve their scope, performance, and ruggedness. The optimized procedures use a static headspace introduction system with a gas chromatograph equipped with a flame ionization detector. This article describes some of the key changes made to the USP published procedures, including use of dimethyl sulfoxide (DMSO) or dimethylformamide (DMF) as the solvent, addition of 5 mL of water and 1 mL of sample (dissolved in DMSO or DMF) to the headspace vial, use of a 3:1 GC split ratio, and use of new matrix-matched system suitability solutions. These procedures were verified with two different active pharmaceutical ingredients—hydroxyzine pamoate and prednisone. In the investigation, the more polar material (hydroxyzine pamoate) showed greater recoveries for the optimized procedures when prepared in DMSO. The less polar material (prednisone) typically had greater recoveries in DMF for the optimized procedures. During experimentation, insights into sample preparation, additional types of headspace instrumentation, solvent purity, and other parameters were also gained.