Enhanced oxidative damage to DNA, lipids, and proteins and levels of some antioxidant enzymes, cytokines, and heat shock proteins in patients infected with influenza H1N1 virus

Overweight and obesity is becoming widespread enough to generate an acceptable and misleading social status. By 2030, in the USA up to 86 % of adults will be overweight or obese. Some selected statistical data based on the body mass index (BMI) indicated that overweight was not associated with increased mortality, this provoked a conceivable interest. Added to this is the observation that while the prevalence of obesity is dramatically increasing, the cardiovascular mortality and life expectancy in the European Union and USA has improved. When more sensitive indicators of body adiposity and its distribution than the BMI, like the waist-thigh ratio in both sexes and the waist-hip ratio in women are projected on mortality, it becomes obvious that even overweight is associated with an increased health risk. Gaining excessive body fat is a continuous, frequently progressive process. Present obesity epidemic in childhood will manifest with deleterious consequences only in future years when adolescents reach adulthood. Prevention is thus essential even before the overweight sets in. Improved life expectancy observed in large populations despite obesity epidemic, is a favourable medical success in the management of hypertension, of serum lipid disorders and diabetes. While encouraging, when it is observed in large population, it does not take away the potential health risk of a metabolic disorder in an individual who is overweight (Fig. 7, Ref. 25).

Role of alkyl hydroperoxide reductase (AhpC) in the biofilm formation of Campylobacter jejuni

Biofilm formation of Campylobacter jejuni, a major cause of human gastroenteritis, contributes to the survival of this pathogenic bacterium in different environmental niches; however, molecular mechanisms for its biofilm formation have not been fully understood yet. In this study, the role of oxidative stress resistance in biofilm formation was investigated using mutants defective in catalase (KatA), superoxide dismutase (SodB), and alkyl hydroperoxide reductase (AhpC). Biofilm formation was substantially increased in an ahpC mutant compared to the wild type, and katA and sodB mutants. In contrast to the augmented biofilm formation of the ahpC mutant, a strain overexpressing ahpC exhibited reduced biofilm formation. A perR mutant and a CosR-overexpression strain, both of which upregulate ahpC, also displayed decreased biofilms. However, the introduction of the ahpC mutation to the perR mutant and the CosR-overexpression strain substantially enhanced biofilm formation. The ahpC mutant accumulated more total reactive oxygen species and lipid hydroperoxides than the wild type, and the treatment of the ahpC mutant with antioxidants reduced biofilm formation to the wild-type level. Confocal microscopy analysis showed more microcolonies were developed in the ahpC mutant than the wild type. These results successfully demonstrate that AhpC plays an important role in the biofilm formation of C. jejuni.

Target optimization for peptide nucleic acid (PNA)-mediated antisense inhibition of the CmeABC multidrug efflux pump in Campylobacter jejuni

OBJECTIVES

CmeABC is a resistance-nodulation-cell division (RND)-type multidrug efflux pump conferring resistance to clinically important antibiotics in Campylobacter. This study aimed to identify the optimal target sites for the inhibition of CmeABC with antisense peptide nucleic acid (PNA).

METHODS

Eighteen PNAs were designed to bind to the translational initiation regions of cmeABC, spanning the ribosome-binding site (RBS) and the start codon of the cmeABC genes. Campylobacter jejuni was treated with CmeABC-specific PNAs (CmeABC-PNAs) at various concentrations and subjected to western blotting to measure changes in the level of CmeABC expression. The MICs of ciprofloxacin and erythromycin were measured to evaluate the impact of CmeABC knockdown on antibiotic susceptibility.

RESULTS

While antisense PNA significantly affected CmeA and CmeB expression, interestingly, CmeC expression was not altered by any of the CmeC-PNAs used in this study. A CmeA-PNA targeting the RBS of cmeA and its upstream region reduced CmeA expression most efficiently, and CmeB expression was most significantly decreased by PNA binding to the RBS of cmeB and its downstream region. CmeA- and CmeB-PNAs increased the susceptibility of C. jejuni to ciprofloxacin and erythromycin in proportion to the inhibition levels observed in western blotting.

CONCLUSIONS

The cmeA gene is the best target to knockdown CmeABC with antisense PNA. The RBS is the major target for the PNA-mediated antisense inhibition of CmeABC. However, regions in its vicinity also significantly influence the effectiveness of the PNA-based knockdown of CmeABC.

Clinical significance of CD151 overexpression in subtypes of invasive breast cancer

Background:

CD151 is a member of the tetraspanin family, which interacts with laminin-binding integrins and other tetraspanins. This protein is implicated in motility, invasion, and metastasis of cancer cells, but the prevalence of CD151 expression in subtypes of breast cancers and its influence on clinical outcome remains to be evaluated.

Methods and results:

The immunohistochemistry-based tissue microarray analysis showed that 127 (14.3%) cases overexpressed CD151 among 886 breast cancer patients. CD151 overexpression was found to be significantly associated with larger tumour size, higher nodal stage, advanced stage, absence of oestrogen receptor and progesterone receptor, and human epidermal growth factor receptor 2 overexpression. CD151 overexpression resulted in poorer overall survival (OS) (P<0.001) and disease-free survival (P=0.02), and stage II and III patients with CD151 overexpression demonstrated substantially poorer OS (P=0.0474 and 0.0169). In the five subtypes analyses, CD151 overexpression retained its adverse impact on OS in the Luminal A (P=0.0105) and quintuple-negative breast cancer (QNBC) subtypes, one subgroup of triple-negative breast cancer (P=0.0170). Multivariate analysis that included stage, subtype, and adjuvant chemotherapy showed that CD151 overexpression was independently associated with poor OS in invasive breast cancer.

Conclusion:

CD151 overexpression may be a potential molecular therapeutic target for breast cancer, especially in QNBC subtype and more advanced stages of breast cancer.

ε-Acetamidocaproic acid pharmacokinetics in rats with gastric ulcer or small bowel inflammation

The pharmacokinetics of ϵ-acetamidocaproic acid (AACA) were evaluated after the intravenous and oral administration of an antiulcer agent, zinc acexamate (ZAC) at a dose of 20 mg kg⁻¹ (ion pairing between zinc and AACA) in rats with indomethacin-induced acute gastric ulcer (IAGU) or indomethacin-induced small bowel inflammation (ISBI). In IAGU rats, the area under the curves (AUCs) of AACA were significantly smaller after both the intravenous (551 versus 1270 μg min ml⁻¹) and oral (397 versus 562 μg min ml⁻¹) administration of ZAC than controls, possible due to the significantly faster CL(R) of AACA. In ISBI rats, however, the AUCs of AACA were comparable with controls after both the intravenous and oral administration of ZAC. In IAGU rats, the significantly smaller AUCs of AACA were due to the significantly faster CL(R) (due to the decreased urinary pH by indomethacin treatment) than controls. AACA has a basic secondary amine group. On the other hand, the comparable AUCs of AACA in ISBI rats were due to the comparable CL(R)s between ISBI and control rats. AACA was excreted in the urine via active renal tubular secretion in all rats studied.

Defects in neural stem cell proliferation and olfaction in Chd7 deficient mice indicate a mechanism for hyposmia in human CHARGE syndrome

Mutations in CHD7, a chromodomain gene, are present in a majority of individuals with CHARGE syndrome, a multiple anomaly disorder characterized by ocular Coloboma, Heart defects, Atresia of the choanae, Retarded growth and development, Genital hypoplasia and Ear anomalies. The clinical features of CHARGE syndrome are highly variable and incompletely penetrant. Olfactory dysfunction is a common feature in CHARGE syndrome and has been potentially linked to primary olfactory bulb defects, but no data confirming this mechanistic link have been reported. On the basis of these observations, we hypothesized that loss of Chd7 disrupts mammalian olfactory tissue development and function. We found severe defects in olfaction in individuals with CHD7 mutations and CHARGE, and loss of odor evoked electro-olfactogram responses in Chd7 deficient mice, suggesting reduced olfaction is due to a dysfunctional olfactory epithelium. Chd7 expression was high in basal olfactory epithelial neural stem cells and down-regulated in mature olfactory sensory neurons. We observed smaller olfactory bulbs, reduced olfactory sensory neurons, and disorganized epithelial ultrastructure in Chd7 mutant mice, despite apparently normal functional cilia and sustentacular cells. Significant reductions in the proliferation of neural stem cells and regeneration of olfactory sensory neurons in the mature Chd7(Gt/+) olfactory epithelium indicate critical roles for Chd7 in regulating neurogenesis. These studies provide evidence that mammalian olfactory dysfunction due to Chd7 haploinsufficiency is linked to primary defects in olfactory neural stem cell proliferation and may influence olfactory bulb development.

Reader accuracy and confidence in diagnosing diffuse lung disease on high-resolution computed tomography of the lungs: impact of sampling frequency

BACKGROUND

The accuracy of the number of high-resolution computed tomography (HRCT) images necessary to diagnose diffuse lung disease (DLD) is not well established.

PURPOSE

To evaluate the impact of HRCT sampling frequency on reader confidence and accuracy for diagnosing DLD.

MATERIAL AND METHODS

HRCT images of 100 consecutive patients with proven DLD were reviewed. They were: 48 usual interstitial pneumonia, 22 sarcoidosis, six hypersensitivity pneumonitis, five each of desquamative interstitial pneumonitis, eosinophilic granulomatosis, and lymphangioleiomyomatosis, and nine others. Inspiratory images at 1-cm increments throughout the lungs and three specified levels formed complete and limited examinations. In random order, three experts (readers 1, 2, and 3) ranked their top three diagnoses and rated confidence for their top diagnosis, independently and blinded to clinical information.

RESULTS

Using the complete versus limited examinations for correct first-choice diagnosis, accuracy for reader 1 (R1) was 81% versus 80%, respectively, for reader 2 (R2) 70% versus 70%, and for reader 3 (R3) 64% versus 59%. Reader accuracy within their top three choices for complete versus limited examinations was: R1 91% versus 91% of cases, respectively, R2 84% versus 83%, and R3 79% versus 72% of cases. No statistically significant differences were found between the diagnosis methods (P=0.28 for first diagnosis and P=0.17 for top three choices). The confidence intervals for individual raters showed considerable overlap, and the point estimates are almost identical. The mean interreader agreement for complete versus limited HRCT for both top and top three diagnoses were the same (moderate and fair, respectively). The mean intrareader agreement between complete and limited HRCT for top and top three diagnoses were substantial and moderate, respectively.

CONCLUSION

Overall reader accuracy and confidence in diagnosis did not significantly differ when fewer or more HRCT images were used.

Early androgen exposure modulates spatial cognition in congenital adrenal hyperplasia (CAH)

Major questions remain about the exact role of hormones in cognition. Furthermore, the extent to which early perturbation in steroid function affects human brain development continues to be a wide open area of research. Congenital adrenal hyperplasia (CAH), a genetic disorder of steroid dysfunction characterized in part by in utero over-production of testosterone, was used as a natural model for addressing this question. Here, CAH (n=54, mean age=17.53, 31 female) patients were compared to healthy age- and sex-matched individuals (n=55, mean age=19.02, 22 female) on a virtual equivalent of the Morris Water Maze task [Morris, R., 1984. Developments of a water-maze procedure for studying spatial learning in the rat. J. Neurosci. Methods 11, 47-60], an established measure of sex differences in spatial cognition in rodents. Findings revealed that females with CAH with the most severe form of the disease and expected highest level of in utero exposure to androgens were found to perform similarly to both healthy males and CAH males, whereas strong sex differences were apparent in milder forms of the disorder and in controls. Moreover, advanced bone age, an indicator of long-term childhood exposure to testosterone was correlated with improved performance. The results indicate that individuals exposed to both excess androgens prenatally and prolonged exposure during childhood may manifest long-lasting changes in cognitive function. Such finding suggests a pivotal role of hormonal function on brain development in humans, mirroring results from the animal literature.

First Report of Chestnut Ink Disease by Phytophthora katsurae on Chestnut in Korea

Since the late 1970s, chestnut (Castanea spp.) has been one of the most commonly cultivated nuts for human consumption in Korea. In 1998, as much as 100,000 t of chestnut seeds were produced from 79,000 ha of plantations for export (2). Most cultivated chestnuts are hybrids of Castanea crenata and C. mollissima that have resulted in 27 cultivars commonly grown in Korea. In 2004, dead trees of two cultivars (Tsukuba and Ginyose) from different locations were found with black ooze emanating from reddish, sunken tissues on the trunks. When the bark was peeled off, a distinct necrotic region was observed on the basal trunk with the discoloration extending up and girdling the trunk. In November 2006, a Phytophthora species was isolated from the necrotic areas with a CARP selective medium (4). Eleven isolates were obtained from three locations: Hadong, Hapcheon, and Youngqwang. The isolates produced numerous homothallic oogonia (34.0 to 46.2 × 21.9 to 26.7 μm) with warty protuberances on the surface. Antheridia were amphigynous with long, funnel-shaped stalks at the base of the oogonia. The formation of papillate, ovoid to obpyriform sporangia (17.0 to 38.9 × 14.6 to 29.2 μm) was induced by cold treatment in filtered (through 25-μm particle retention) creek water or deionized water. Chlamydospores were not observed. Comparison of the rDNA ITS sequence using ITS1/4 (3) showed 99.6% similarity to P. katsurae (GenBank Accession No. AF266771) with three base pair differences. All eleven isolates showed identical ITS sequences. Pathogenicity studies were conducted on excised three 15-cm-long × 5-cm-diameter logs from each of three chestnut cultivars (Moriwase, Parkmi 2, and Ibuki). Bark (5 mm in diameter) was taken with a cork borer on each log followed by inoculation with a 5-mm agar disk of two isolates, PH.K01 and PH.K07. The logs were placed in a moist chamber for 7 days. Noninoculated controls consisted of log sections from each cultivar treated with agar disks. The pathogencity test was repeated three times. The entire log of cv. Parkmi 2 became necrotic, whereas the other two cultivars developed only small lesions (P < 0.0001). The noninoculated control logs of each cultivar did not develop lesions and no pathogen was reisolated from them. This suggests that cultivars differ in susceptibility. P. katsurae (synonym = P. castaneae) was first described from Japan in 1931. P. cambivora, P. cinnamomi, and P. katsurae are commonly responsible for ink disease on chestnut species in Europe, the United States, and Asia (1). The impact of P. katsurae on chestnut production in Korea is currently unknown. References: (1) A. Boutard et al. The West. Chestnut. 3:6, 2001. (2) S. H. Lee et al. J. Korean For. Soc. 95:61, 2006. (3) E. Oh et al. Forest Pathol. 36:388, 2006. (4) T. J. White et al. Page 315 in: PCR Protocols. Academic Press Inc., New York, 1990.

Phytophthora ramorum Colonizes Tanoak Xylem and Is Associated with Reduced Stem Water Transport

ABSTRACT Isolation, detection with diagnostic polymerase chain reaction (PCR), and microscopy demonstrated the presence of Phytophthora ramorum in the sapwood of mature, naturally infected tanoak (Lithocarpus densiflorus) trees. The pathogen was strongly associated with discolored sapwood (P < 0.001), and was recovered or detected from 83% of discolored sapwood tissue samples. Hyphae were abundant in the xylem vessels, ray parenchyma, and fiber tracheids. Chlamydospores were observed in the vessels. Studies of log inoculation indicated that P. ramorum readily colonized sapwood from inoculum placed in the bark, cambium, or sapwood. After 8 weeks, radial spread of P. ramorum in sapwood averaged 3.0 to 3.3 cm and axial spread averaged 12.4 to 18.8 cm. A field study was conducted to determine if trees with infected xylem had reduced sap flux and reduced specific conductivity relative to noninfected control trees. Sap flux was monitored with heat-diffusion sensors and tissue samples near the sensors were subsequently tested for P. ramorum. Adjacent wood sections were excised and specific conductivity measured. Both midday sap flux and specific conductivity were significantly reduced in infected trees versus noninfected control trees. Vessel diameter distributions did not differ significantly among the two treatments, but tyloses were more abundant in infected than in noninfected trees. Implications for pathogenesis, symptomology, and epidemiology are discussed.

White University Students' Responses to Societal Racism

The purpose of this investigation was to extend earlier conceptual and empirical literature on the ways in which White individuals respond to societal racism. To this end, the authors conducted in-depth interviews to examine 11 midwestern, non-Hispanic, White university students' reactions and experiences related to individual and institutional forms of racism perpetrated against people of color. We used the consensual qualitative research method to analyze these data. Results suggested that White students varied in their understanding of and responses to racism. Three topic domains, each consisting of a number of subcategories, reflected participants' varied responses to racism: (a) affective, (b) social, and (c) cognitive. Findings add to the existing literature by identifying in greater depth the multiple ways in which dominant group members respond to societal racism. Limitations and future research directions are discussed.

Fractality in complex networks: critical and supercritical skeletons

Fractal scaling--a power-law behavior of the number of boxes needed to tile a given network with respect to the lateral size of the box--is studied. We introduce a box-covering algorithm that is a modified version of the original algorithm introduced by Song [Nature (London) 433, 392 (2005)]; this algorithm enables easy implementation. Fractal networks are viewed as comprising a skeleton and shortcuts. The skeleton, embedded underneath the original network, is a special type of spanning tree based on the edge betweenness centrality; it provides a scaffold for the fractality of the network. When the skeleton is regarded as a branching tree, it exhibits a plateau in the mean branching number as a function of the distance from a root. For nonfractal networks, on the other hand, the mean branching number decays to zero without forming a plateau. Based on these observations, we construct a fractal network model by combining a random branching tree and local shortcuts. The scaffold branching tree can be either critical or supercritical, depending on the small worldness of a given network. For the network constructed from the critical (supercritical) branching tree, the average number of vertices within a given box grows with the lateral size of the box according to a power-law (an exponential) form in the cluster-growing method. The critical and supercritical skeletons are observed in protein interaction networks and the World Wide Web, respectively. The distribution of box masses, i.e., the number of vertices within each box, follows a power law Pm(M) approximately M(-eta). The exponent eta depends on the box lateral size l(B). For small values of l(B), eta is equal to the degree exponent gamma of a given scale-free network, whereas eta approaches the exponent tau=gamma/(gamma-1) as l(B) increases, which is the exponent of the cluster-size distribution of the random branching tree. Finally, we study the perimeter H(alpha) of a given box alpha, i.e., the number of edges connected to different boxes from a given box alpha as a function of the box mass M(B,alpha). It is obtained that the average perimeter over the boxes with box mass M(B) is likely to scale as <H(M(B))> approximately M(B), irrespective of the box size l(B).

Synchronization transition of heterogeneously coupled oscillators on scale-free networks

We investigate the synchronization transition of the modified Kuramoto model where the oscillators form a scale-free network with degree exponent lambda . An oscillator of degree k_{i} is coupled to its neighboring oscillators with asymmetric and degree-dependent coupling in the form of Jk_{i};{eta-1} . By invoking the mean-field approach, we find eight different synchronization transition behaviors depending on the values of eta and lambda , and derive the critical exponents associated with the order parameter and the finite-size scaling in each case. The synchronization transition point J_{c} is determined as being zero (finite) when eta>lambda-2 (eta<lambda-2) . The synchronization transition is also studied from the perspective of cluster formation of synchronized vertices. The cluster-size distribution and the largest cluster size as a function of the system size are derived for each case using the generating function technique. Our analytic results are confirmed by numerical simulations.

Diagnostic accuracy of a fibrosis serum panel (FIBROSpect II) compared with Knodell and Ishak liver biopsy scores in chronic hepatitis C patients

Liver biopsy is the primary method of assessing liver injury in hepatitis C patients. FIBROSpect II (FS), a diagnostic panel of three extracellular matrix remodelling markers, may be useful as a noninvasive alternative to this procedure. The purpose of this study was to correlate FS results with liver fibrosis scores to determine if this test is sufficiently accurate to be a viable alternative to liver biopsy. A total of 142 serum specimens were evaluated for fibrosis with FS and were compared with Knodell and Ishak fibrosis scores. FS reports an index score ranging from 0.1 to 1.0, which corresponds to the probability of progressive liver fibrosis. Using a FS index cut-off of 0.42, 50 of 54 patients with Ishak 3-6 were classified as having advanced fibrosis (METAVIR F2-F4) and 58 of 88 patients with Ishak 0-2 as having no/mild fibrosis (METAVIR F0-F1), resulting in a sensitivity of 93%, specificity of 66%, and an overall test accuracy of 76%. With a 38% prevalence of advanced fibrosis, the negative predictive value was 94% and positive predictive value was 63%. A biopsy length of > or = 2 cm was associated with higher concordance between FS results and liver fibrosis scores (P = 0.01). FS was clinically useful in ruling out advanced fibrosis in hepatitis C by identifying patients with mild disease in whom treatment could be deferred. The limitation of this test is its decreased sensitivity and specificity in the middle of the test's reporting range between scores of 0.42 and 0.80.

The anxiety-like phenotype of 5-HT receptor null mice is associated with genetic background-specific perturbations in the prefrontal cortex GABA-glutamate system

A deficit in the serotonin 5-HT(1A) receptor has been found in panic and post-traumatic stress disorders, and genetic inactivation of the receptor results in an anxiety-like phenotype in mice on both the C57Bl6 and Swiss-Webster genetic backgrounds. Anxiety is associated with increased neuronal activity in the prefrontal cortex and here we describe changes in glutamate and GABA uptake of C57Bl6 receptor null mice. Although these alterations were not present in Swiss-Webster null mice, we have previously reported reductions in GABA(A) receptor expression in these but not in C57Bl6 null mice. This demonstrates that inactivation of the 5-HT(1A) receptor elicits different and genetic background-dependent perturbations in the prefrontal cortex GABA/glutamate system. These perturbations can result in a change in the balance between excitation and inhibition, and indeed both C57Bl6 and Swiss-Webster null mice show signs of increased neuronal excitability. Because neuronal activity in the prefrontal cortex controls the extent of response to anxiogenic stimuli, the genetic background-specific perturbations in glutamate and GABA neurotransmission in C57Bl6 and Swiss-Webster 5-HT(1A) receptor null mice may contribute to their shared anxiety phenotype. Our study shows that multiple strains of genetically altered mice could help us to understand the common and individual features of anxiety.

Network analysis of online bidding activity

With the advent of digital media, people are increasingly resorting to online channels for commercial transactions. The online auction is a prototypical example. In such online transactions, the pattern of bidding activity is more complex than traditional offline transactions; this is because the number of bidders participating in a given transaction is not bounded and the bidders can also easily respond to the bidding instantaneously. By using the recently developed network theory, we study the interaction patterns between bidders (items) who (that) are connected when they bid for the same item (if the item is bid by the same bidder). The resulting network is analyzed by using the hierarchical clustering algorithm, which is used for clustering analysis for expression data from DNA microarrays. A dendrogram is constructed for the item subcategories; this dendrogram is compared to a traditional classification scheme. The implication of the difference between the two is discussed.