Embryonic and early development of the Zagros tooth‐carp,Aphanius vladykovi (Actinopterygii: Cyprinodontidae)

The embryonic and early larval development of laboratory reared Zagros tooth‐carp, Aphanius vladykovi Coad, 1988, are described and illustrated. Development and embryogenesis start with the external fertilization of sticky, transparent and spherical telolecithal/macrolecithal eggs with a mean diameter of 1.61± 0.12 mm and it continues with meroblastic/radial cleavage, blastulation/blastula formation, epibolic cell migration during gastrulation and organogenesis resulting in a newly hatched larvae of 5.23 ± 0.09 mm in length with attached yolk sac at about 164 hr (at 24 ± 1°C) after fertilization.     

Molecular structure,DNA binding mode,photophysical properties and recommendations for use of SYBR Gold

SYBR Gold is a commonly used and particularly bright fluorescent DNA stain, however, its chemical structure is unknown and its binding mode to DNA remains controversial. Here, we solve the structure of SYBR Gold by NMR and mass spectrometry to be [2-(4-{[diethyl(methyl)ammonio]methyl}phenyl)-6-methoxy-1-methyl-4-{[(2Z)-3-methyl-1,3-benzoxazol-2-ylidene]methyl}quinolin-1-ium] and determine its extinction coefficient. We quantitate SYBR Gold binding to DNA using two complementary approaches. First, we use single-molecule magnetic tweezers (MT) to determine the effects of SYBR Gold binding on DNA length and twist. The MT assay reveals systematic lengthening and unwinding of DNA by 19.1° ± 0.7° per molecule upon binding, consistent with intercalation, similar to the related dye SYBR Green I. We complement the MT data with spectroscopic characterization of SYBR Gold. The data are well described by a global binding model for dye concentrations ≤2.5 μM, with parameters that quantitatively agree with the MT results. The fluorescence increases linearly with the number of intercalated SYBR Gold molecules up to dye concentrations of ∼2.5 μM, where quenching and inner filter effects become relevant. In summary, we provide a mechanistic understanding of DNA-SYBR Gold interactions and present practical guidelines for optimal DNA detection and quantitative DNA sensing applications using SYBR Gold.     

Genome-wide association study of shank length and diameter at different developmental stages in chicken F2 resource population

In order to find SNPs and genes affecting shank traits, we performed a GWAS in a chicken F2 population of eight half-sib families from five hatches derived from reciprocal crosses between an Arian fast-growing line and an Urmia indigenous slow-growing chicken. A total of 308 birds were genotyped using a 60K chicken SNP chip. Shank traits including shank length and diameter were measured weekly from birth to 12 weeks of age. A generalized linear model and a compressed mixed linear model (CMLM) were applied to achieve the significant regions. The value of the average genomic inflation factor (λ statistic) of the CMLM model (0.99) indicated that the CMLM was more effective than the generalized linear model in controlling the population structure. The genes surrounding significant SNPs and their biological functions were identified from NCBI, Ensembl and UniProt databases. The results indicated that 12 SNPs at 12 different ages passed the LD-adjusted 5% Bonferroni significant threshold. Two SNPs were significant for shank length and nine SNPs were significant for shank diameter. The significant SNPs were located near to or inside 11 candidate genes. The results showed that a number of significant SNPs in the middle ages were higher than the rest. The MXRA8 gene was related to the significant SNP at week 1 that promotes proliferation of growth plate chondrocytes. A unique SNP of Gga_rs16689511 located on chicken Z chromosome within the LOC101747628 gene was related to shank length at three different ages of birds (weeks 8, 9 and 11). The significant SNPs for shank diameter were found at weeks 4 and 7 (four and five SNPs respectively). The identifications of SNPs and genes here could contribute to a better understanding of the genetic control of shank traits in chicken.     

Suppression of Sensitivity to Drugs and Antibiotics by High External Cation Concentrations in Fission Yeast

Background

Potassium ion homeostasis plays an important role in regulating membrane potential and therefore resistance to cations, antibiotics and chemotherapeutic agents in Schizosaccharomyces pombe and other yeasts. However, the precise relationship between drug resistance in S. pombe and external potassium concentrations (particularly in its natural habitats) remains unclear. S. pombe can tolerate a wide range of external potassium concentrations which in turn affect plasma membrane polarization. We thus hypothesized that high external potassium concentrations suppress the sensitivity of this yeast to various drugs.

Methods

We have investigated the effect of external KCl concentrations on the sensitivity of S. pombe cells to a wide range of antibiotics, antimicrobial agents and chemotherapeutic drugs. We employed survival assays, immunoblotting and microscopy for these studies.

Results

We demonstrate that KCl, and to a lesser extent NaCl and RbCl can suppress the sensitivity of S. pombe to a wide range of antibiotics. Ammonium chloride and potassium hydrogen sulphate also suppressed drug sensitivity. This effect appears to depend in part on changes to membrane polarization and membrane transport proteins. Interestingly, we have found little relationship between the suppressive effect of KCl on sensitivity and the structure, polarity or solubility of the various compounds investigated.

Conclusions

High concentrations of external potassium and other cations suppress sensitivity to a wide range of drugs in S. pombe. Potassium-rich environments may thus provide S. pombe a competitive advantage in nature. Modulating potassium ion homeostasis may sensitize pathogenic fungi to antifungal agents.     

Association between N142D genetic polymorphism of <Emphasis Type="Italic">GSTO2</Emphasis> and susceptibility to colorectal cancer

Expression pattern analysis has been revealed that glutathione S-transferase omega 2 (GSTO2, a member of class omega) is ubiquitously expressed. Over expression of GSTO2 induced apoptosis. The gene encoding GSTO2 was localized to human chromosome 10q24.3, a region that may harbor gene(s) involved in the developing of colorectal cancer. To investigate the association between GSTO2 N142D genetic polymorphism and susceptibility to colorectal cancer the present study was done. We studied 63 (26 females, 37 males) colorectal cancer patients and 126 (52 females, 74 males) healthy individuals. The control subjects were frequency matched for age and gender with the colorectal cancer group. The genotypes were performed using RFLP-PCR method. The ND and DD genotypes were not associated with risk of colorectal cancer, in comparison with the NN genotype. Family history for cancer in the first degree of relatives significantly differed between cases and controls (P = 0.012). The profiles of GSTO2 genotypes and family history in control and cancerous groups were compared to each other. Subjects with NN genotype and positive family history significantly were at high risk to develop colorectal cancer in comparison with subjects with DD or ND genotypes and negative family history (P = 0.003). Present findings indicating that GSTO2 NN genotype increase the risk of colorectal cancer in persons with positive family history for cancer in the first degree relatives.     

Prevalence of oral and dental disorders in institutionalised elderly people in Rasht,Iran

doi:10.1111/j.1741‐2358.2009.00313.x
Prevalence of oral and dental disorders in institutionalised elderly people in Rasht, Iran Objective: The aim of this study was to determine the prevalence of dental and oral mucosal lesions in institutionalised elderly people in Rasht. Background: Oral health in the elderly people is important to tailor the health programmes for this increasing age group within the population. Methods: A total of 216 elderly people residing in a geriatric nursing home were included in the study. Subjects were interviewed and examined clinically and registered in a data collection form and analysed using spss version 11 program (SPSS Inc, Chicago, Illinois, USA). Results: The prevalence of dental and oral disorders was 44.9% and 86.1% respectively. The most frequent oral disorders were dry mouth (42.1%), fissure tongue (25.9%), atrophic of tongue (25%), sublingual varicosity (22.7%), burning sensation (16.7%) and varix (15.3%). The prevalence of edentulousness was 56% (95%CI: 49–63%). The mean level of retained teeth was 3.22. The odds of an oral mucosal disorder in females were significantly more than in males (OR = 2.79, 95%CI: 1.25–6.23). Discussion: The findings revealed a high prevalence of dental and oral disorders in institutionalised elderly people in Rasht in comparison to similar studies. The mean of retained teeth was also much lower than in other reports. Therefore, the necessity for regular oral examination of these rapidly expanding age groups of people is essential.     

Novel spiro[indene-1,2′-quinazolin]-4′(3′H)-one derivatives as potent anticonvulsant agents: One-pot synthesis,in vivo biological evaluation,and molecular docking studies

A new series of spiro[indene-1,2′-quinazolin]-4′(3′H)-one derivatives 4a–m were synthesized via a one-pot method and evaluated for anticonvulsant activities using pentylenetetrazole (PTZ) and maximal electroshock (MES)-induced seizures. Obtained results demonstrated that these compounds have not anticonvulsant activity in PTZ test while are active in the MES test. Among the synthesized compounds, the best anticonvulsant activity was obtained with compound 4h . This compound also was not neurotoxic. Given that the title new compounds have the pharmacophore requirement for benzodiazepine (BZD) receptor agonist, the most potent compound was assayed in vivo and in silico as BZD receptor agonist. After treatment with flumazenil as a standard BZD receptor antagonist, anticonvulsant activity of compound 4h decreased. Therefore, the involvement of BZD receptors in anticonvulsant activity of this compound confirmed. Furthermore, docking study of compound 4h in the BZD-binding site of GABA_A receptor confirmed that this compound interacted with the important residues.