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191.
In the current study, an attempt was made to encapsulate assembly pheromone using natural polymer, chitosan. Chitosan beads were prepared by incorporating assembly pheromone in conjunction with an acaricide, namely, deltamethrin. In the in vitro bioassay, the test beads attracted and killed 79 % of unfed larvae, 88 % of unfed nymphs and 61 % of unfed adults of the brown dog tick, Rhipicephalus sanguineus, in 24 h of exposure. Field trials were carried out to attract and kill the pre-parasitic environmental stages. The beads were dispersed onto specially designed devices and they were placed in infested kennels. The devices were observed after 10 days.  相似文献   
192.
Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death worldwide and is influenced by both genetic determinants and smoking. We identified genomic regions from 56 lung-tissue gene-expression microarrays and used them to select 889 SNPs to be tested for association with COPD. We genotyped SNPs in 389 severe COPD cases from the National Emphysema Treatment Trial and 424 cigarette-smoking controls from the Normative Aging Study. A total of 71 autosomal SNPs demonstrated at least nominal significance with COPD susceptibility (p = 3.4 × 10−6 to 0.05). These 71 SNPs were evaluated in a family-based study of 127 probands with severe, early-onset COPD and 822 of their family members in the Boston Early-Onset COPD Study. We combined p values from the case-control and family-based analyses, setting p = 5.60 × 10−5 as a conservative threshold for significance. Three SNPs in the iron regulatory protein 2 (IREB2) gene met this stringent threshold for significance, and four other IREB2 SNPs demonstrated combined p < 0.02. We demonstrated replication of association for these seven IREB2 SNPs (all p values ≤ 0.02) in a family-based study of 3117 subjects from the International COPD Genetics Network; combined p values across all cohorts for the main phenotype of interest ranged from 1.6 × 10−7 to 6.4 × 10−4. IREB2 protein and mRNA were increased in lung-tissue samples from COPD subjects in comparison to controls. In summary, gene-expression and genetic-association results have implicated IREB2 as a COPD susceptibility gene.  相似文献   
193.
Geomyces destructans is the etiologic agent of bat geomycosis, commonly referred to as white nose syndrome (WNS). This infection has caused severe morbidity and mortality in little brown bats (Myotis lucifugus) and has also spread to other bat species with significant decline in the populations. Currently, G. destructans infection is identified by culture, ITS–PCR, and histopathology. We hypothesized that a real-time PCR assay would considerably improve detection of G. destructans in bats. The 100 bp sequence of the Alpha-L-Rhamnosidase gene was validated as a target for real-time PCR. The assay sensitivity was determined from serial dilution of DNA extracted from G. destructans conidia (5 × 10−1–5 × 107), and the specificity was tested using DNA from 30 closely and distantly related fungi and 5 common bacterial pathogens. The real-time PCR assay was highly sensitive with detection limit of two G. destructans conidia per reaction at 40 PCR cycles. The assay was also highly specific as none of the other fungal or bacterial DNA cross-reacted in the real-time PCR assay. One hundred and forty-seven bat tissue samples, suspected of infection with G. destructans, were used to compare the real-time PCR assay to other methods employed for the detection of G. destructans. Real-time PCR was highly sensitive with 80 of 147 (55%) samples testing positive for G. destructans DNA. In comparison, histopathology examination revealed 64/147 (44%) positive samples. The internal transcribed spacer (ITS)–PCR yielded positive amplicon for G. destructans from 37 tissue samples (25%). The least sensitive assay was the fungal culture with only 17 tissue samples (12%) yielding G. destructans in culture. The data suggested that the real-time PCR assay is highly promising for rapid, sensitive, and specific identification of G. destructans. Further trials and inter-laboratory comparisons of this novel assay are recommended to improve the diagnosis of bat geomycosis.  相似文献   
194.
The level of diacylglycerol (DAG) in the Golgi apparatus is crucial for protein transport to the plasma membrane. Studies in budding yeast indicate that Sec14p, a phosphatidylinositol (PI)-transfer protein, is involved in regulating DAG homeostasis in the Golgi complex. Here, we show that Nir2, a peripheral Golgi protein containing a PI-transfer domain, is essential for maintaining the structural and functional integrity of the Golgi apparatus in mammalian cells. Depletion of Nir2 by RNAi leads to substantial inhibition of protein transport from the trans-Golgi network to the plasma membrane, and causes a reduction in the DAG level in the Golgi apparatus. Remarkably, inactivation of cytidine [corrected] 5'-diphosphate (CDP)-choline pathway for phosphatidylcholine biosynthesis restores both effects. These results indicate that Nir2 is involved in maintaining a critical DAG pool in the Golgi apparatus by regulating its consumption via the CDP-choline pathway, demonstrating the interface between secretion from the Golgi and lipid homeostasis.  相似文献   
195.

Objective

To highlight the salient features of metastatic malignancies involving the penis, with special reference to the primary tumour sites, metastatic mechanisms, clinical features, differential diagnosis, treatment and prognosis.

Methods

A comprehensive search of the literature was performed using MEDLINE and EMBASE, using the keywords 'penis', 'secondary malignancy', 'metastasis' and 'malignant priapism' to identify reviews and case reports of secondary penile malignancy. A case of rare clinical presentation of metastatic penile lesion is presented along with the review of the literature.

Conclusion

Secondary malignancy of the penis is a rare clinical entity, despite the rich vascularisation of this organ. The majority of metastatic lesions take their origin from the neighbouring genito-urinary organs, mainly prostate and bladder. These lesions are often associated with disseminated malignancy and hence have a poor outcome. Nodular or ulcerative lesions involving the corpora cavernosa or priapism are the main modes of clinical presentation. In most cases, only palliative or supportive therapy is indicated.
  相似文献   
196.
197.
Whether translation initiation factor 4E (eIF4E), the mRNA cap binding and rate-limiting factor required for translation, is a target for cytotoxicity and cell death induced by cadmium, a human carcinogen, was investigated. Exposure of human cell lines, HCT15, PLC/PR/5, HeLa, and Chang, to cadmium chloride resulted in cytotoxicity and cell death, and this was associated with a significant decrease in eIF4E protein levels. Similarly, specific silencing of the expression of the eIF4E gene, caused by a small interfering RNA, resulted in significant cytotoxicity and cell death. On the other hand, overexpression of the eIF4E gene was protective against the cadmium-induced cytotoxicity and cell death. Further studies revealed the absence of alterations in the eIF4E mRNA level in the cadmium-treated cells despite their decreased eIF4E protein level. In addition, exposure of cells to cadmium resulted in enhanced ubiquitination of eIF4E protein while inhibitors of proteasome activity reversed the cadmium-induced decrease of eIF4E protein. Exposure of cells to cadmium, as well as the specific silencing of eIF4E gene, also resulted in decreased cellular levels of cyclin D1, a critical cell cycle and growth regulating gene, suggesting that the observed inhibition of cyclin D1 gene expression in the cadmium-treated cells is most likely due to decreased cellular level of eIF4E. Taken together, our results demonstrate that the exposure of cells to cadmium chloride resulted in cytotoxicity and cell death due to enhanced ubiquitination and consequent proteolysis of eIF4E protein, which in turn diminished cellular levels of critical genes such as cyclin D1.  相似文献   
198.
The big data storage is a challenge in a post genome era. Hence, there is a need for high performance computing solutions for managing large genomic data. Therefore, it is of interest to describe a parallel-computing approach using message-passing library for distributing the different compression stages in clusters. The genomic compression helps to reduce the on disk“foot print” of large data volumes of sequences. This supports the computational infrastructure for a more efficient archiving. The approach was shown to find utility in 21 Eukaryotic genomes using stratified sampling in this report. The method achieves an average of 6-fold disk space reduction with three times better compression time than COMRAD.

Availability

The source codes are written in C using message passing libraries and are available at https:// sourceforge.net/ projects/ comradmpi/files / COMRADMPI/  相似文献   
199.
ATP synthesis is a critical and universal life process carried out by ATP synthases. Whereas eukaryotic and prokaryotic ATP synthases are well characterized, archaeal ATP synthases are relatively poorly understood. The hyperthermophilic archaeal parasite, Nanoarcheaum equitans, lacks several subunits of the ATP synthase and is suspected to be energetically dependent on its host, Ignicoccus hospitalis. This suggests that this ATP synthase might be a rudimentary machine. Here, we report the crystal structures and biophysical studies of the regulatory subunit, NeqB, the apo-NeqAB, and NeqAB in complex with nucleotides, ADP, and adenylyl-imidodiphosphate (non-hydrolysable analog of ATP). NeqB is ∼20 amino acids shorter at its C terminus than its homologs, but this does not impede its binding with NeqA to form the complex. The heterodimeric NeqAB complex assumes a closed, rigid conformation irrespective of nucleotide binding; this differs from its homologs, which require conformational changes for catalytic activity. Thus, although N. equitans possesses an ATP synthase core A3B3 hexameric complex, it might not function as a bona fide ATP synthase.  相似文献   
200.
Abstract

3-β-D-Ribofuranosylpyazolo[4,3-d]pyrimidines (formycins)1 modified in the heteroaromatic moiety are of biological interest as analogues of adenosine and guanosine, and have been the objects of intensive synthetic chemical effort by several groups.2-9 2′-Deoxynucleosides2c,2d,7b,13 and other analogties of the formycins modified in the sugar moiety10-12 are also of potential interest, but have been less extensively studied. Examples of the 2′-deoxyribonucleoside type known to date include the 2′-deoxy-6-thioguanosine analogue 1, the 2′-deoxyadenosine (dAdo) analogue 2 (2′-deoxyformycin A),10,13 and the 2-chloro-2′-deoxyadenosine analogue 3.7b Compound 2 was found to be 10-15 times more potent than 2′-deoxyadenosine as an inhibitor of the growth of S49 cells, a murine lymphoma line of T-cell origin.13 Activity depended on 5′- phosphorylation, since mutants lacking the enzymes adenosine kinase (AK) and deoxycytidine kinase (dCK) were insensitive to the drug. Furthermore, activity was comparable in the presence and absence of an AK inhibitor, suggesting that 2, unlike dAdo, may be a poor substrate for adenosine deaminase. That 5′-phosphorylation of 2 was mediated by AK rather than dCK was indicated by the fact that miitants lacking only dCK retained sensitivity. This contrasted with the behavior of dAdo, which is known to be n substrate for both AK and dCK.14  相似文献   
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