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31.
Two compounds (trans-1R,3R-chrysanthemyl R-2-methylbutanoate and R-lavandulyl R-2-methylbutanoate) identified from aeration extracts of virgin female Madeira mealybug, Phenacoccus madeirensis Green (Hemiptera: Pseudococcidae), were synthesized and tested in field bioassays in northern Taiwan over a 1-mo period. In total, 1,492 male P. madeirensis were captured in sticky traps. Our results showed that 1 microg of synthetic trans-1R,3R-chrysanthemyl R-2-methylbutanoate released from a plastic tube dispenser was attractive to the mealybugs. Different stereoisomers of chrysanthemyl 2-methylbutanoate also were tested. The insect-produced stereoisomer was the most attractive of all the isomers tested, and the stereochemistry of the acid moiety proved to be more critical than that of the alcohol moiety. The minor component found in extracts, R-lavandulyl R-2-methylbutanoate, alone was not attractive to male Madeira mealybugs nor did it act synergistically or additively with the main component.  相似文献   
32.
The ectoenzyme CD38 catalyzes the production of cyclic ADP-ribose (cADPR) and ADP-ribose (ADPR) from its substrate, NAD(+). Both products of the CD38 enzyme reaction play important roles in signal transduction, as cADPR regulates calcium release from intracellular stores and ADPR controls cation entry through the plasma membrane channel TRPM2. We previously demonstrated that CD38 and the cADPR generated by CD38 regulate calcium signaling in leukocytes stimulated with some, but not all, chemokines and controls leukocyte migration to inflammatory sites. However, it is not known whether the other CD38 product, ADPR, also regulates leukocyte trafficking In this study we characterize 8-bromo (8Br)-ADPR, a novel compound that specifically inhibits ADPR-activated cation influx without affecting other key calcium release and entry pathways. Using 8Br-ADPR, we demonstrate that ADPR controls calcium influx and chemotaxis in mouse neutrophils and dendritic cells activated through chemokine receptors that rely on CD38 and cADPR for activity, including mouse FPR1, CXCR4, and CCR7. Furthermore, we show that the calcium and chemotactic responses of leukocytes are not dependent on poly-ADP-ribose polymerase 1 (PARP-1), another potential source of ADPR in some leukocytes. Finally, we demonstrate that NAD(+) analogues specifically block calcium influx and migration of chemokine-stimulated neutrophils without affecting PARP-1-dependent calcium responses. Collectively, these data identify ADPR as a new and important second messenger of mouse neutrophil and dendritic cell migration, suggest that CD38, rather than PARP-1, may be an important source of ADPR in these cells, and indicate that inhibitors of ADPR-gated calcium entry, such as 8Br-ADPR, have the potential to be used as anti-inflammatory agents.  相似文献   
33.
The characterization of garlic germplasm improves its utility, despite the fact that garlic hasn't been used much in the past. Garlic has an untapped genetic pool of immense economic and medicinal value in India. Hence, using heuristic core collection approach, a core set of 46 accessions were selected from 625 Indian garlic accessions based on 13 quantitative and five qualitative traits. The statistical measures (CV per cent, CR per cent, VR per cent) were used to sort the core set using Shannon-Wiener diversity index and the Nei diversity index. In addition, the variation within the core set was tested for 18 agro-morphological and six biochemical characteristics (allicin, phenol content, pyruvic acid, protein, allyl methyl thiosulfinate (AMTHS), and methyl allyl thiosulfinate (MATHS)). Further study of the core set's molecular diversity was performed using sequence related amplified polymorphism (SRAP) markers, which revealed a wide range of diversity among the core set's accessions, with an average polymorphism efficiency (PE) of 80.59 percent, polymorphism information content (PIC) of 0.29, effective multiplex ratio (EMR) of 3.51, and marker index (MI) of 0.99. The findings of this study will be useful in identifying high-yielding, elite garlic germplasm lines with the trait of interest. Since this core set is indicative of total germplasm, these selected breeding lines will be used for genetic improvement of garlic in the future.  相似文献   
34.

Background

Circulating tumor cells (CTCs) are cancer cells that can be isolated via liquid biopsy from blood and can be phenotypically and genetically characterized to provide critical information for guiding cancer treatment. Current analysis of CTCs is hindered by the throughput, selectivity and specificity of devices or assays used in CTC detection and isolation.

Methodology/Principal Findings

Here, we enriched and characterized putative CTCs from blood samples of patients with both advanced stage metastatic breast and lung cancers using a novel multiplexed spiral microfluidic chip. This system detected putative CTCs under high sensitivity (100%, n = 56) (Breast cancer samples: 12–1275 CTCs/ml; Lung cancer samples: 10–1535 CTCs/ml) rapidly from clinically relevant blood volumes (7.5 ml under 5 min). Blood samples were completely separated into plasma, CTCs and PBMCs components and each fraction were characterized with immunophenotyping (Pan-cytokeratin/CD45, CD44/CD24, EpCAM), fluorescence in-situ hybridization (FISH) (EML4-ALK) or targeted somatic mutation analysis. We used an ultra-sensitive mass spectrometry based system to highlight the presence of an EGFR-activating mutation in both isolated CTCs and plasma cell-free DNA (cf-DNA), and demonstrate concordance with the original tumor-biopsy samples.

Conclusions/Significance

We have clinically validated our multiplexed microfluidic chip for the ultra high-throughput, low-cost and label-free enrichment of CTCs. Retrieved cells were unlabeled and viable, enabling potential propagation and real-time downstream analysis using next generation sequencing (NGS) or proteomic analysis.  相似文献   
35.
D Pandey  V Vanya  S Bhagat  B Vs  J Shetty 《PloS one》2012,7(7):e40619

Background

As preventing cancer with the help of a vaccine is a comparatively new concept, awareness and education about it will have important implication in the implementation of this strategy.

Materials and Methods

Present explorative questionnaire based survey included 618 MBBS students for final analysis.

Results

Majority of participants (89.6%) were well aware of the preventable nature of cervical cancer. Most of them (89.2%) knew that necessary factor responsible for cervical cancer is infection with high risk HPV. Awareness regarding the availability of vaccine against cervical cancer was 75.6%. Females had a better awareness regarding availability of vaccine, target population for vaccination and about the catch up program. Overall acceptance of HPV vaccine among the population studied was 67.8%. Medical teaching had a definitive impact on the understanding of this important public health issue. Females seemed to be more ready to accept the vaccine and recommend it to others. For our study population the most common source of information was medical school teaching. Majority of participants agreed that the most important obstacle in implementation of HPV vaccination program in our country is inadequate information and 86.2% wanted to be educated by experts in this regard.

Conclusion

HPV vaccine for primary prevention of cervical cancer is a relatively new concept. Health professional will be able to play a pivotal role in popularizing this strategy.  相似文献   
36.
Citrus jambhiri (rough lemon) is considered a major rootstock source for a number of Citrus species. A simple method for micropropagation from nodal segments is reported. Nodal segments of C. jambhiri were inoculated on MS medium supplemented with different concentrations and combinations of 6-benzylaminopurine (BAP), kinetin, and N6-(2-isopentenyl) adenosine (2iP). Maximum multiple shoot regeneration response (75?%) was observed with BAP at 3?mg?l?1. Shoots were multiplied for 30?d on fresh medium with similar composition. A total of 67?% of the cultures showed multiplication with the optimum number of shoots (4.02) and height of shoots (1.81?cm) with BAP (3?mg?l?1) alone. Maximum rooting response (87?%) was observed with naphthaleneacetic acid at 0.5?mg?l?1. Transverse sections of shoot stems obtained in vivo (sampled from seedlings) and in vitro (regenerated from nodal segments), showed similar anatomies. Randomly amplified polymorphic DNA analysis confirmed that all the regenerated plants were genetically identical to their donor plant, suggesting absence of detectable genetic variation in the regenerated plantlets.  相似文献   
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In adult rats, removal of one ovary leads to an acute albeit transient rise in serum follicle stimulating hormone and an increase in the weight of the remaining ovary. In an attempt to correlate the high titre of endogenous follicle stimulating hormone with the changes taking place at the macromolecular level, the phenomenon of compensatory ovarian hypertrophy was studied for one cycle after hemiovariectomy at metoestrus in the adult, cycling female rats derived from the Holtzman strain. The significant finding with respect to hormonal changes was an acute follicle stimulating hormone surge commencing 6h post-unilateral ovariectomy, reaching a maximum at 12 h and declining thereafter, hitherto not reported in the Holtzman strain. Serum luteinizing hormone, prolactin, oestradiol-17β and testosterone remained unaltered while progesterone showed a decline at 6 h after surgery. There was an increase in the number of healthy class III (> 350 μm) follicles with a concomitant drop in atretic class III follicles 24 h post-unilateral ovariectomy. Analysis for DNA, RNA and protein content showed that all three constituents registered a continuous rise in the hypertrophying ovary up to 120h after surgery. When expressed as ?g/mg ovarian weight, the increase in DNA reached a maximum at 24 h and declined thereafter. The kinetics of DNA synthesis was followed by pulse labelling with [3H] thymidine at 18, 24, 36 and 48 h after unilateral ovariectomy. Maximum incorporation occurred at 36 h. Autoradiographic studies showed that the granulosa cells of healthy follicles preferentially incorporated the label. In an extension of this study, it was found that labelling index registered a significant increase following ovariectomy, the maximum being reached at 24 h especially in classIII follicles. The results clearly point out the crucial role of hyperplasia in the response of the contralateral ovary to the surgery and implicate the rise in follicle stimulating hormone as the primary signal for initiation of such a response. This raises the question whether in compensatory ovarian hypertrophy follicle stimulating hormone has a mitogenic role  相似文献   
40.
Previous studies have suggested that transglutaminase has a role in the internalization of some polypeptide hormones and is inhibited by the antibiotic, bacitracin. Bacitracin has been used in insulin-receptor studies to inhibit extracellular degradation of 125I-labelled insulin. The aim of this study was to investigate bacitracin's effect on 125I-labelled insulin-receptor interactions in isolated rat hepatocytes. 1 g/l bacitracin increased cell-associated 125I-labelled insulin at 20, 30 and 37°C (P < 0.001, 0.0005 and 0.0005, respectively). At 5 and 15°C (internalization does not occur), bacitracin did not affect cell-associated 125I-labelled insulin. The bacitracin effect was concentration dependent, increasing to 2 g/l. Scatchard analysis showed that bacitracin did not alter insulin receptor affinity or number. 1 g/l bacitracin abolished the effect of chloroquine. The increased cell-associated radioactivity with bacitracin was surface-bound in nature. 0.5 g/l bacitracin decreased 125I-labelled insulin degradation in hepatocyte suspensions (P < 0.001) and in buffer previously incubated with hepatocytes (P < 0.0005). More 125I-labelled insulin remained associated with cells during dissociation studies at 37°C when the buffer contained 1 g/l bacitracin. Label that appeared in the buffer after 60 min was significantly more intact in the presence of bacitracin (P < 0.025). These results suggest that bacitracin retards the internalization of 125I-labelled insulin in isolated rat hepatocytes.  相似文献   
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