Haplorchis taichui as a Possible Etiologic Agent of Irritable Bowel Syndrome-Like Symptoms

The aim of this study is to clarify the clinical features of Haplorchis taichui infection in humans in Nan Province, Thailand, and to correlate the clinical features with irritable bowel syndrome (IBS)-like symptoms. In this study area, only H. taichui, but neither other minute intestinal flukes nor small liver flukes were endemic. The degree of infection was determined by fecal egg counts and also by collecting adult worms after deworming. The signs and symptoms of individual patients together with their hematological and biochemical laboratory data were gathered to evaluate the relationship between the clinical features and the severity of infection. Special emphasis was made to elucidate the possible similarities of the clinical features of H. taichui infection and IBS-like symptoms. The results showed useful clinical information and the significant (> 50%) proportion of haplorchiasis patients complained of abdominal pain, lassitude, and flatulence, which were the important diagnostic symptoms of IBS. This study has reported a possible link between H. taichui and IBS, and H. taichui might probably play a role in the etiology of these IBS-like symptoms.     

No evidence for increased extinction proneness with decreasing effective population size in a parasitoid with complementary sex determination and fertile diploid males

Background  

In species with single locus complementary sex determination (sl-CSD), the sex of individuals depends on their genotype at one single locus with multiple alleles. Haploid individuals are always males. Diploid individuals are females when heterozygous, but males when homozygous at the sex-determining locus. Diploid males are typically unviable or effectively sterile, hence imposing a genetic load on populations. Diploid males are produced from matings of partners that share an allele at the sex-determining locus. The lower the allelic diversity at the sex-determining locus, the more diploid males are produced, ultimately impairing the growth of populations and jeopardizing their persistence. The gregarious endoparasitoid wasp Cotesia glomerata is one of only two known species with sl-CSD and fertile diploid males.     

Mechanisms of non-apoptotic programmed cell death in diabetes and heart failure

Programmed cell elimination is an important pathological mediator of disease. Multiple pathways to programmed cell death have been delineated, including apoptosis, autophagy and programmed necrosis. Cross-talk between the signaling pathways mediating each process has made it difficult to define specific mechanisms of in vivo programmed cell death. For this reason, many “apoptotic” diseases may involve other death signaling pathways. Recent advances in genetic complementation using mouse knockout models are helping to dissect apoptotic and necrotic cell death in different pathological states. The current state of research in this area is reviewed, focusing upon new findings describing the role of programmed necrosis induced by the mitochondrial permeability transition in mouse models of heart failure and diabetes.Key words: apoptosis, necrosis, mitochondrial permeability transition pore     

Weak base dispiro-1,2,4-trioxolanes: potent antimalarial ozonides

Thirty weak base 1,2,4-dispiro trioxolanes (secondary ozonides) were synthesized. Amino amide trioxolanes had the best combination of antimalarial and biopharmaceutical properties. Guanidine, aminoxy, and amino acid trioxolanes had poor antimalarial activity. Lipophilic trioxolanes were less stable metabolically than their more polar counterparts.     

Positional stability of single double-strand breaks in mammalian cells

Formation of cancerous translocations requires the illegitimate joining of chromosomes containing double-strand breaks (DSBs). It is unknown how broken chromosome ends find their translocation partners within the cell nucleus. Here, we have visualized and quantitatively analysed the dynamics of single DSBs in living mammalian cells. We demonstrate that broken ends are positionally stable and unable to roam the cell nucleus. Immobilization of broken chromosome ends requires the DNA-end binding protein Ku80, but is independent of DNA repair factors, H2AX, the MRN complex and the cohesion complex. DSBs preferentially undergo translocations with neighbouring chromosomes and loss of local positional constraint correlates with elevated genomic instability. These results support a contact-first model in which chromosome translocations predominantly form among spatially proximal DSBs.     

Nucleosomes in the neighborhood: New roles for chromatin modifications in replication origin control

The importance of local chromatin structure in regulating replication initiation has become increasingly apparent. Most recently, histone methylation and nucleosome positioning have been added to the list of modifications demonstrated to regulate origins. In particular, the methylation states of H3K4, H3K36 and H4K20 have been associated with establishing active, repressed or poised origins depending on the timing and extent of methylation. The stability and precise positioning of nucleosomes has also been demonstrated to affect replication efficiency. Although it is not yet clear how these modifications alter the behavior of specific replication factors, ample evidence establishes their role in maintaining coordinated replication. This review will summarize recent advances in understanding these aspects of chromatin structure in DNA replication origin control.Key words: chromatin, histone methylation, nucleosome positioning, nucleosome stability, origin, post-translational modification, replication     

Fusarium species complex and mycotoxins in grain maize from maize hybrid trials and from grower's fields

Aims: To quantify and to compare the occurrence of Fusarium species in maize kernels and stalk pieces, to analyse mycotoxins in kernels and maize crop residues, to evaluate two approaches to obtain kernel samples and to compare two methods for mycotoxin analyses. Methods and Results: The occurrence of Fusarium species in maize kernels and stalk pieces from a three‐year maize hybrid trial and 12 kernel samples from grower’s fields was assessed. Nine to 16 different Fusarium species were detected in maize kernels and stalks. In kernels, F. graminearum, F. verticillioides and F. proliferatum were the most prevalent species whereas in stalks, they were F. equiseti, F. proliferatum and F. verticillioides. In 2006, 68% of the kernel samples exceeded the recommended limit for pig feed for deoxynivalenol (DON) and 42% for zearalenone (ZON), respectively. Similarly, 75% of the samples from grower’s fields exceeded the limits for DON and 50% for ZON. In maize crop residues, toxin concentrations ranged from 2·6 to 15·3 mg kg^?1 for DON and from 0·7 to 7·4 mg kg^?1 for ZON. Both approaches to obtain maize kernel samples were valid, and a strong correlation between mycotoxin analysis using ELISA and LC‐MS/MS was found. Conclusions: The contamination of maize kernels, stalk pieces and remaining crop residues with various mycotoxins could pose a risk not only to animal health but also to the environment. With the hand‐picked sample, the entire Fusarium complex can be estimated, whereas combine harvested samples are more representative for the mycotoxin contents in harvested goods. Significance and Impact of the Study: This is the first multi‐year study investigating mycotoxin contamination in maize kernels as well as in crop residues. The results indicate a high need to identify cropping factors influencing the infection of maize by Fusarium species to establish recommendations for growers.     

mRNA expression levels of the biological factors uPAR, uPAR-del4/5, and rab31, displaying prognostic value in breast cancer, are not clinically relevant in advanced ovarian cancer

High tumor tissue mRNA expression of the tumor biological factors uPAR, uPAR-del4/5, or rab31 is associated with shorter distant metastasis-free and overall survival in breast cancer patients. To evaluate whether these factors are also clinically relevant in ovarian cancer, we quantified the respective mRNA levels in primary tumor tissue of advanced ovarian cancer patients (n=103) and evaluated their association with clinicopathological parameters and patients' prognosis. mRNA expression levels of all three markers did not show any significant association with overall or progression-free survival, demonstrating that these factors have no prognostic value in advanced ovarian cancer.     

Thermoregulation behaviour in codling moth larvae

Abstract. The thermoregulation behaviour of the codling moth, Cydia pomonella, is investigated in temperature gradient experiments with larvae feeding within apples, and with mature larvae searching for cocooning sites. Feeding larvae appear to prefer the apple hemisphere with a higher temperature (i.e. they build larger cavities in the radiated, warmer part of the fruit). The proportion of larval cavities in the warmer hemisphere is positively related to increasing apple temperature on that side, as well as to the temperature difference between the warm and the cool fruit hemisphere. The mechanism in feeding larvae can be termed as cryptic basking because, during microhabitat selection, the caterpillars exploit temperature differences that are caused explicitly by incident solar radiation. Fifth-instar larvae in search of cocooning sites show no temperature preference within the large gradient offered (9–29 °C), with no difference between males and females. During larval development, the insect changes its thermoregulation behaviour in response to a possible shift in benefits of an elevated body temperature with respect to environmental conditions. Both the thermoregulation behaviour and such a shift of behavioural response should be respected when simulating body temperatures of the species.