Sustained microtubule treadmilling in Arabidopsis cortical arrays

Plant cells create highly structured microtubule arrays at the cell cortex without a central organizing center to anchor the microtubule ends. In vivo imaging of individual microtubules in Arabidopsis plants revealed that new microtubules are initiated at the cell cortex and exhibit dynamics at both ends. Polymerization-biased dynamic instability at one end and slow depolymerization at the other end result in sustained microtubule migration across the cell cortex by a hybrid treadmilling mechanism. This motility causes widespread microtubule repositioning and contributes to changes in array organization through microtubule reorientation and bundling.     

Molecular characterization of a Squalene epoxidase gene in dermatophyte pathogen Trichophyton tonsurans

BACKGROUND: Trichophyton tonsurans is one of the dermatophyte fungi which invades the skin and hair of human. Several properties of this fungus have been investigated so far. However a few studies were carried out in the field of molecular biology of this fungus. In the present study, we tried to identify the Squalene epoxidase gene which is related to synthesis of ergosterol in this fungus. METHODS: Pairs of 23 and 24 nucleotides primers were designed from highly conserved regions of the similar genes in other fungi. Mentioned primers were utilized in PCR by using isolated genomic DNA of T. tonsurans whereas the PCR fragments were then sequenced. RESULTS AND CONCLUSION: Nucleotides (n = 558) have been sequenced from this new gene which encodes a polypeptide with 186 amino acids. Sequences comparison in gene data banks (NCBI, NIH) for this part of DNA and its deduced amino acid revealed significant homology with members of the eukaryotic Squalene epoxidase.     

Neonatal jaundice: knowledge and practice of Iranian mothers with icteric newborns

The present study was conducted on a group of Iranian mothers with icteric newborn in order to identify any wrong knowledge and improper practices related to the neonatal jaundice. Such an estimate of knowledge and practices of mothers may be required for implementing the educational programs on which the preventive measures of kernicterus are principally thought to be depended. Between June 2004 and February 2007, 1666 mothers with icteric newborn hospitalized at a single center were enrolled. A questionnaire was used to assess the participants' knowledge and practice of neonatal jaundice. A knowledge score was calculated based on the responses. The mean knowledge score was 3.38 +/- 1.23 (out of 6). About 77% of the mothers had moderate-to-high level of knowledge of neonatal jaundice. Approximately one-third of the mothers consulted a physician within 24 h of appearance of jaundice and 13.8% declared that they waited and managed their children with traditional remedies until they sought medical advices. Furthermore, 32.2% of the mothers discontinued feeding their icteric offspring with colored foods and colostrums. Hence, 42.8% of the mothers acted weakly with regard to their icteric offspring. The health care workers were the participants' major source of information about neonatal jaundice. The present study determined a fairly adequate knowledge of Iranian mothers about the neonatal jaundice with incomparable level of related practices. The findings of this study should be considered seriously by the local health centers and the medical professionals to provide consistent information about jaundice and its causes for the parents.     

Evaluation of various hCG treatment strategies applied to domesticated pikeperch (Sander lucioperca) broodstock on nest-spawning performance

The aim of the present study was to evaluate the effects of hCG injections on reproductive efficiency by hCG treatment in both male or female brooders of domesticated pikeperch (Sander lucioperca) in the first generation. The study consisted of four treatments based on hormone injection to male or female brooders including T1: both sexes were injected, T2: only females were injected, T3: only males were injected, and T4: without hormone injection. Each treatment which included 14 males and 12 females were introduced to a single rectangular concrete tank with one spawning nest for each mate (a total of 12 nests per tank). Fish were injected by a single dose of 200 IU/kg hCG before transferring to mating tanks. After mating, nests containing fertilized eggs were transferred to circular concrete tanks for incubation and hatching of embryos. According to the results, treatments T3 and T4 did not respond to hormonal stimulation and no fish were spawned. Treatments T1 and T2 showed a positive response to hormone injection. Latency time, fertilization rate, and hatching rate showed no significant difference between T1 and T2 (P?>?0.05), but the number of responded females was significantly higher in T2 (P?<?0.05). The results of the present study demonstrated that it is possible to perform the semi-artificial propagation of domesticated pikeperch via injecting with 200 IU/kg hCG just to females, without the need for hormonal stimulation for males.