1/Nc1/N_c Rotational Corrections to gAg_A and Isovector Magnetic Moment of the Nucleon

The $1/N_c$ rotational corrections to the axial vector constant and the isovector magnetic moment of the nucleon are studied in the Nambu -- Jona-Lasinio model. We follow a semiclassical quantization procedure in terms of path integrals in which we can include perturbatively corrections in powers of angular velocity $\Omega \sim \frac 1{N_c}$. We find non-zero $1/N_c$ order corrections from both the valence and the Dirac sea quarks. These corrections are large enough to resolve the long-standing problem of a strong underestimation of both $g_A$ and $\mu^{IV}$ in the leading order. The axial constant $g_A$ is well reproduced, whereas the isovector magnetic moment $\mu^{IV}$ is still underestimated by 25 \%.Comment: (Revtex), 10 pages (3 figures available on request), report RUB-TPII-53/9

Evaluation of chloroform/methanol extraction to facilitate the study of membrane proteins of non-model plants

Membrane proteins are of great interest to plant physiologists because of their important function in many physiological processes. However, their study is hampered by their low abundance and poor solubility in aqueous buffers. Proteomics studies of non-model plants are generally restricted to gel-based methods. Unfortunately, all gel-based techniques for membrane proteomics lack resolving power. Therefore, a very stringent enrichment method is needed before protein separation. In this study, protein extraction in a mixture of chloroform and methanol in combination with gel electrophoresis is evaluated as a method to study membrane proteins in non-model plants. Benefits as well as disadvantages of the method are discussed. To demonstrate the pitfalls of working with non-model plants and to give a proof of principle, the method was first applied to whole leaves of the model plant Arabidopsis. Subsequently, a comparison with proteins extracted from leaves of the non-model plant, banana, was made. To estimate the tissue and organelle specificity of the method, it was also applied on banana meristems. Abundant membrane or lipid-associated proteins could be identified in both tissues, with the leaf extract yielding a higher number of membrane proteins

Self-medication with antibiotics for the treatment of menstrual symptoms in southwest Nigeria: a cross-sectional study

Background: Self-medication with antibiotics is an important factor contributing to the development of bacterial antibiotic resistance. The purpose of this study was to evaluate the prevalence of self-medication with antibiotics for the treatment of menstrual symptoms among university women in Southwest Nigeria. Methods: A cross-sectional survey was administered to female undergraduate and graduate students (n = 706) at four universities in Southwest Nigeria in 2008. The universities were selected by convenience and the study samples within each university were randomly selected cluster samples. The survey was self-administered and included questions pertaining to menstrual symptoms, analgesic and antibiotic use patterns, and demographics. Data were analyzed using descriptive statistics and logistic regression. Results: The response rate was 95.4%. Eighty-six percent (95% CI: 83-88%) of participants experienced menstrual symptoms, and 39% (95% CI: 36-43%) reported using analgesics to treat them. Overall, 24% (95% CI: 21-27%) of participants reported self-medicated use of antibiotics to treat the following menstrual symptoms: cramps, bloating, heavy bleeding, headaches, pimples/acne, moodiness, tender breasts, backache, joint and muscle pain. Factors associated with this usage were: lower levels of education (Odds Ratio (OR): 2.8, 95% CI: 1.1-7.1, p-value: 0.03); nonscience major (OR: 1.58, 95% CI: 1.03-2.50, p-value: 0.04); usage of analgesics (OR: 3.17, 95% CI: 2.07-4.86, p-value: <0.001); and mild to extreme heavy bleeding (OR: 1.64, 95% CI: 1.01-2.67, p-value: 0.05) and pimples/acne (OR: 1.57, 95% CI: 0.98-2.54, p-value: 0.06). Ampicillin, tetracycline, ciprofloxacin and metronidazole were used to treat the most symptoms. Doctors or nurses (6%, 95% CI: 4-7%), friends (6%, 95% CI: 4-7%) and family members (7%, 95% CI: 5-8%) were most likely to recommend the use of antibiotics for menstrual symptoms, while these drugs were most often obtained from local chemists or pharmacists (10.2%, 95% CI: 8-12%). Conclusions: This is the first formal study to report that approximately 1 out of 4 university women surveyed in Southwest Nigeria self-medicate with antibiotics to treat menstrual symptoms. This practice could provide monthly, low-dose exposures to antibiotics among users. Further studies are necessary to evaluate the impacts of selfmedication on student health

Phenylalanine ammonia lyase under combined effects of enhanced UV-B radiation and allelopathy stress

This study examined the effects of UV-B radiation and allelochemical stress induced by ferulic acid (FA) on the activity of phenylalanine ammonia lyase (PAL; EC 4.3.1.5) at metabolic and molecular levels in two cucumber genotypes differing in tolerance to cold and disease, in order to determine any interaction between stress effects and genotype response. Stresses were applied simultaneously, sequentially, and singly. In both genotypes, several days of UV radiation retarded growth up to 36%. The effect of FA was not significant. The response to a particular stress, including the effect on PAL activation, was enhanced by simultaneous application of the two stresses. PAL transcription was not correlated with the increase of PAL activity. Exposure to UV-B, FA, and combined UV-B and FA was detrimental to both genotypes but to different extents. The response was not correlated with the genotype of cold and disease sensitivity. PAL activity and its transcription seem to be involved in UV and allelochemical stress, but not related to the plants' tolerance of these stresses

Homology of DNA sequences encompassing the malignant hyperthermia mutation site in the human, porcine, and zebrine ryrl gene

The RYR1 gene encoding the Ca²⁺ channel of sarcoplasmic reticulum of human skeletal muscle has been cloned and its nucleotide sequence has been determined earlier. We have used the polymerase chain reaction single strand conformation polymorphism (PCR-SSCP), and sequencing analysis for human, porcine (Sus scrofa), and zebrine (Equus grevyi) ryanodine receptor (ryrl) gene. The fragment of exon 17 of the ryr1 gene was characterized by a high homology between all the analysed species (substitution of a nucleotide is underlined): porcine ryr1 ¹⁸³⁴GTG GCC GTG CGC TCC AAC CAA GAT CT¹⁸⁵⁹ human RYR1 ¹⁸³¹GTG GCC GTG CGC TCC AAC CAA GAT CT¹⁸⁵⁶ zebrine ryr1 GTG GCC GTG CGC TCC AAC CAA GAC CT

Genes putatively implicated in secondary metabolism

Genes putatively implicated in secondary metabolism</p

<b>Flow cytometric determination of ploidy level and reproduction modes in </b><b><i>Hypericum perforatum</i></b><b> cv. Helos</b>

Flow cytometry was carried out to determine the DNA content and thus the ploidy level of embryo and endosperm cells in 50 randomly selected seeds. This allows us to infer the ploidy level and reproductive modes of H. perforatum cv. Helos. The results suggest that H. perforatum cv. Helos is tetraploid and facultatively apomictic.</p