AstA Signaling Functions as an Evolutionary Conserved Mechanism Timing Juvenile to Adult Transition

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Resistance to macrolide, lincosamide and streptogramin antibiotics in staphylococci isolated in Istanbul, Turkey

The purpose of this study was to investigate the prevalence and genetic mechanisms of erythromycin resistance in staphylococci. A total of 102 erythromycin resistant non-duplicate clinical isolates of staphylococci [78 coagulase negative stapylococci (CNS), 24 Staphylococcus aureus] were collected between October 2003 and August 2004 in Istanbul Faculty of Medicine in Turkey. The majority of the isolates were from blood and urine specimens. Antimicrobial susceptibilities were determined by the agar dilution procedure and the resistance phenotypes by the double disk induction test. A multiplex PCR was performed, using primers specific for erm(A), erm(B), erm(C), and msrA genes. Among the 78 CNS isolates, 57.8% expressed the MLSB-constitutive, 20.6% the MLSB-inducible, and 21.6% the MSB phenotypes. By PCR, 78.2% of these isolates harbored the erm(C) gene, 8.9% erm(A), 6.4% erm(B), and 11.5% msrA genes. In S. aureus, the constitutive MLSB (58.3%) was more common than the inducible phenotype (20.8%). erm(A) was detected in 50% and erm(C) in 62.5% of the isolates, while 37.5% contained both erm(A) and erm(C). erm(C)-associated macrolide resistance was the most prevalent in CNS, while erm(C) and erm(A, C) was the most prevalent in S. aureus.     

Translocation of bacteria from the gut to the eggs triggers maternal transgenerational immune priming in Tribolium castaneum

Invertebrates can be primed to enhance their protection against pathogens they have encountered before. This enhanced immunity can be passed maternally or paternally to the offspring and is known as transgenerational immune priming. We challenged larvae of the red flour beetle Tribolium castaneum by feeding them on diets supplemented with Escherichia coli, Micrococcus luteus or Pseudomonas entomophila, thus mimicking natural exposure to pathogens. The oral uptake of bacteria induced immunity-related genes in the offspring, but did not affect the methylation status of the egg DNA. However, we observed the translocation of bacteria or bacterial fragments from the gut to the developing eggs via the female reproductive system. Such translocating microbial elicitors are postulated to trigger bacterial strain-specific immune responses in the offspring and provide an alternative mechanistic explanation for maternal transgenerational immune priming in coleopteran insects.     

The spectrum of FMF mutations and genotypes in the referrals to molecular genetic laboratory at Kırıkkale University in Turkey

Familial Mediterranean Fever (FMF) is an autosomal recessive genetic disorder characterised by recurrent and self-limited abdominal pain, synovitis and pleuritis. MEFV gene mutations are responsible from the disease and its protein product, pyrin or marenostrin, plays an essential role in the regulation of the inflammatory reactions. MEFV gene contains 10 exons and most of the mutations have been found on the last exon. Up to date, 152 mutations and polymorpisms have been reported inwhere V726A, M694V, M694I, M680I and E148Q are the most common mutations. In this study, MEFV allele frequencies of 136 individuals (60 from Pediatry, 76 from Internal Medicine) have been evaluated, and compared with each other. Asymptomatic individuals with FMF family history (4 from Pediatry, 6 from Internal Medicine) were excluded from the analysis. The prominent mutations indicated in the Pediatry group are V726A, M694V and M680I (G/C) and with the allele frequency of 0.06, 0.05 and 0.04 respectively while they were E148Q, M694V, M680I (G/C) in the Internal Medicine group with the allele frequency of 0.12, 0.08 and 0.04. The E148Q mutation is significantly overrepresented in the adult referrals (P = 0.02). Mutation on both alleles was observed in only 12% of cases. Overall mutation frequency was low, seen in 26.2% (66/252). However, when only diagnosed patients were analyzed it is 72.7% (16/22). It is also interesting that 63% of individuals are female that there may be sex influence on FMF phenotype.     

Biodiesel production from sunflower,soybean, and waste cooking oils by transesterification using lipase immobilized onto a novel microporous polymer

This study aims at carrying out lipase-catalyzed synthesis of fatty acid methyl esters (biodiesel) from various vegetable oils using lipase immobilized onto a novel microporous polymeric matrix (MPPM) as a low-cost biocatalyst. The research is focused on three aspects of the process: (a) MPPM synthesis (monolithic, bead, and powder forms), (b) microporous polymeric biocatalyst (MPPB) preparation by immobilization of lipase onto MPPM, and (c) biodiesel production by MPPB. Experimental planning of each step of the study was separately carried out in accordance with design of experiment (DoE) based on Taguchi methodology.Microporous polymeric matrix (MPPM) containing aldehyde functional group was synthesized by polyHIPE technique using styrene, divinylbenzene, and polyglutaraldehyde. Thermomyces lanuginosus lipase was covalently attached onto MPPM with 80%, 85%, and 89% immobilization efficiencies using bead, powder, and monolithic forms, respectively. Immobilized enzymes were successfully used for the production of biodiesel using sunflower, soybean, and waste cooking oils. It was shown that immobilized enzymes retain their activities during 10 repeated batch reactions at 25 °C, each lasting 24 h. Since the developed novel method is simple yet effective, it could have a potential to be used industrially for the production of chemicals requiring immobilized lipases.     

Effects of antioxidants on post-thawed bovine sperm and oxidative stress parameters: Antioxidants protect DNA integrity against cryodamage

This study was conducted to determine the effects of methionine, inositol and carnitine on sperm (motility, abnormality, DNA integrity and in vivo fertility) and oxidative stress parameters (lipid peroxidation, total glutathione and antioxidant potential levels) of bovine semen after the freeze–thawing process. Nine ejaculates, collected with the aid of an artificial vagina twice a week from each Simmental bovine, were included in the study. Each ejaculate, splitted into seven equal groups and diluted in Tris-based extender containing methionine (2.5 and 7.5 mM), carnitine (2.5 and 7.5 mM), inositol (2.5 and 7.5 mM) and no additive (control), was cooled to 5 °C and then frozen in 0.25 ml straws. Frozen straws were then thawed individually at 37 °C for 20 s in a water bath for the evaluation.The extender supplemented with 7.5 mM doses of carnitine and inositol led to higher subjective motility percentages (61.9 ± 1.3% and 51.3 ± 1.6%) compared to the other groups. The addition of methionine and carnitine at doses of 2.5 and 7.5 mM and inositol at doses of 7.5 mM provided a greater protective effect in the percentages of total abnormality in comparison to the control and inositol 2.5 mM (P < 0.001). As regards CASA motility, 7.5 mM carnitine (41.6 ± 2.9% and 54.2 ± 4.9%) and inositol (34.9 ± 2.0% and 47.3 ± 2.2%) caused insignificant increases in CASA and total motility in comparison to the other groups. All of the antioxidants at 2.5 and 7.5 mM resulted in lower sperm with damaged DNA than that of control, thus reducing the DNA damage (P < 0.05). No significant differences were observed in CASA progressive motility and sperm motion characteristics among the groups. In fertility results based on 59-day non-returns, no significant differences were observed in non-return rates among groups. As regards biochemical parameters, supplementation with antioxidants did not significantly affect LPO and total GSH levels in comparison to the control group (P > 0.05). The maintenance of AOP level in methionine 2.5 mM was demonstrated to be higher (5.06 ± 0.38 mM) than that of control (0.96 ± 0.29 mM) following the freeze–thawing (P < 0.001). Supplementation with these antioxidants prior to the cryopreservation process protected the DNA integrity against the cryodamage. Furthermore, future research should focus on the molecular mechanisms of the antioxidative effects of the antioxidants methionine, carnitine and inositol during cryopreservation.     

Perturbation of natural killer cell function and receptors during HIV infection

Natural killer (NK) cells play an important role in innate host defenses against a variety of pathogens. A recent report described striking perturbations in the expression of NK cell inhibitory and activating receptors in viremic human immunodeficiency virus (HIV)-infected patients, leading to functional abnormalities in these cells. This finding provides a mechanistic insight into NK cell dysfunction and its possible contribution to the impairment of innate host defenses in HIV-infected individuals.     

Anthropometry of male and female children in Crèches in Turkey

This paper presents the results of an anthropometrical survey conducted on male and female children aged 3, 4 and 5 years in Turkey. A set of 18 body dimensions was taken from 154 males and 132 females. It is considered that the 18 parameters are necessary for the design of school furniture, fittings and equipment in order to minimize musculoskeletal, visual and circulatory problems resulting from badly designed elements. This study identified significant gender differences in a set of 18 anthropometrical measures in this subject group.