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101.
Developmental and gene expression analyses of a cotton naked seed mutant   总被引:13,自引:0,他引:13  
Lee JJ  Hassan OS  Gao W  Wei NE  Kohel RJ  Chen XY  Payton P  Sze SH  Stelly DM  Chen ZJ 《Planta》2006,223(3):418-432
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.  相似文献   
102.

Background:

Moderate alcohol consumption may reduce cardiovascular events, but little is known about its effect on atrial fibrillation in people at high risk of such events. We examined the association between moderate alcohol consumption and the risk of incident atrial fibrillation among older adults with existing cardiovascular disease or diabetes.

Methods:

We analyzed data for 30 433 adults who participated in 2 large antihypertensive drug treatment trials and who had no atrial fibrillation at baseline. The patients were 55 years or older and had a history of cardiovascular disease or diabetes with end-organ damage. We classified levels of alcohol consumption according to median cut-off values for low, moderate and high intake based on guidelines used in various countries, and we defined binge drinking as more than 5 drinks a day. The primary outcome measure was incident atrial fibrillation.

Results:

A total of 2093 patients had incident atrial fibrillation. The age- and sex-standardized incidence rate per 1000 person-years was 14.5 among those with a low level of alcohol consumption, 17.3 among those with a moderate level and 20.8 among those with a high level. Compared with participants who had a low level of consumption, those with higher levels had an increased risk of incident atrial fibrillation (adjusted hazard ratio [HR] 1.14, 95% confidence interval [CI] 1.04–1.26, for moderate consumption; 1.32, 95% CI 0.97–1.80, for high consumption). Results were similar after we excluded binge drinkers. Among those with moderate alcohol consumption, binge drinkers had an increased risk of atrial fibrillation compared with non–binge drinkers (adjusted HR 1.29, 95% CI 1.02–1.62).

Interpretation:

Moderate to high alcohol intake was associated with an increased incidence of atrial fibrillation among people aged 55 or older with cardiovascular disease or diabetes. Among moderate drinkers, the effect of binge drinking on the risk of atrial fibrillation was similar to that of habitual heavy drinking.A trial fibrillation is associated with an increased risk of stroke and a related high burden of mortality and morbidity, both in the general public and among patients with existing cardiovascular disease.1,2 The prevalence of atrial fibrillation increases steadily with age, as do the associated risks, and atrial fibrillation accounts for up to 23.5% of all strokes among elderly people.3Moderate alcohol consumption has been reported to be associated with a reduced risk of cardiovascular disease and all-cause death,1,2 whereas heavy alcohol intake and binge drinking have been associated with an increased risk of stroke,4 cardiovascular disease and all-cause death.5,6 Similarly, heavy drinking and binge drinking are associated with an increased risk of incident atrial fibrillation in the general population.7 However, the association between moderate drinking and incident atrial fibrillation is less consistent and not well understood among older people with existing cardiovascular disease.In this analysis, we examined whether drinking moderate quantities of alcohol, and binge drinking, would be associated with an increased risk of incident atrial fibrillation in a large cohort of people with existing cardiovascular disease or diabetes with end-organ damage who had been followed prospectively in 2 long-term antihypertensive drug treatment trials.  相似文献   
103.
This study aimed to investigate the effects of heat acclimatisation on thermoregulatory responses and work tolerance in trained individuals residing in the tropics. Eighteen male trained soldiers, who are native to a warm and humid climate, performed a total of four heat stress tests donning the Skeletal Battle Order (SBO, 20.5 kg) and Full Battle Order (FBO, 24.7 kg) before (PRE) and after (POST) a 10-day heat acclimatisation programme. The trials were conducted in an environmental chamber (dry bulb temperature: 32 °C, relative humidity: 70%, solar radiation: 400 W/m2). Excluding the data sets of which participants fully completed the heat stress tests (210 min) before and after heat acclimatisation, work tolerance was improved from 173±30 to 201±18 min (∼21%, p<0.05, n=9) following heat acclimatisation. Following heat acclimatisation, chest skin temperature during exercise was lowered in SBO (PRE=36.7±0.3 vs. POST=36.5±0.3 °C, p<0.01) and FBO (PRE=36.8±0.4 vs. POST=36.6±0.3 °C, p<0.01). Ratings of perceived exertion were decreased with SBO and FBO (PRE=11±2; POST=10±2; p<0.05) after heat acclimatisation. Heat acclimatisation had no effects on baseline body core temperature, heart rate and sweat rate across trials (p>0.05). A heat acclimatisation programme improves work tolerance with minimal effects on thermoregulation in trained tropical natives.  相似文献   
104.
Myopia is a complex genetic disorder and a common cause of visual impairment among working age adults. Genome-wide association studies have identified susceptibility loci on chromosomes 15q14 and 15q25 in Caucasian populations of European ancestry. Here, we present a confirmation and meta-analysis study in which we assessed whether these two loci are also associated with myopia in other populations. The study population comprised 31 cohorts from the Consortium of Refractive Error and Myopia (CREAM) representing 4 different continents with 55,177 individuals; 42,845 Caucasians and 12,332 Asians. We performed a meta-analysis of 14 single nucleotide polymorphisms (SNPs) on 15q14 and 5 SNPs on 15q25 using linear regression analysis with spherical equivalent as a quantitative outcome, adjusted for age and sex. We calculated the odds ratio (OR) of myopia versus hyperopia for carriers of the top-SNP alleles using a fixed effects meta-analysis. At locus 15q14, all SNPs were significantly replicated, with the lowest P value 3.87?×?10(-12) for SNP rs634990 in Caucasians, and 9.65?×?10(-4) for rs8032019 in Asians. The overall meta-analysis provided P value 9.20?×?10(-23) for the top SNP rs634990. The risk of myopia versus hyperopia was OR 1.88 (95?% CI 1.64, 2.16, P?相似文献   
105.
Monoclonal antibodies are widely used in the treatment of many B cell lymphomas and certain solid tumors. All currently approved therapeutic monoclonal antibodies are of the immunoglobulin G (IgG) isotype. We hypothesized that tumor-specific monoclonal antibodies of the IgE isotype may serve as effective cancer therapeutics. To test this hypothesis, we produced mouse?Chuman chimeric IgE antibodies specific for the human B cell antigen CD20 and the epithelial antigen MUC1. We demonstrate here that anti-hCD20 IgE antibodies have in vitro cytotoxic activity when used with purified allergic effector cells derived from umbilical cord blood. At an effector-tumor ratio of 2:1, mast cells and tumor-specific IgE induced a 2.5-fold increase in tumor cell death, as compared to control IgE. Similar results were observed when eosinophils were used as effector cells. In an in vivo murine model of breast carcinoma, administration of anti-hMUC1 IgE reduced the growth of MUC1+ tumors by 25?C30?% in hFc??RI transgenic mice. In contrast, local production of IgE and cytokines chemotactic for macrophages, eosinophils and mast cells led to complete tumor eradication. These results suggest that allergic effector cells activated by IgE and cell surface antigens have the capacity to induce tumor cell death in vitro and in vivo. The use of chimeric antibodies and hFc??RI transgenic mice will greatly enhance investigations in the nascent field of allergo-oncology.  相似文献   
106.
In screening for novel photosensitizers for photodynamic therapy, 14 seaweed samples from Port Dickson in Malaysia were collected. Methanolic extracts of these samples were prepared and evaluated for phototoxicity using a short-term cell viability assay, where promyelocytic leukemia cells, HL60 were incubated with the extracts prior to irradiation with a broad spectrum light at 9.6?J?cm?2 (equivalent to 10.5?mW?cm?2 for 10?min). Four of the methanolic extracts demonstrated moderate to strong phototoxicity and bioassay-guided isolation of photosensitizers was carried out on two selected seaweeds to yield a total of eight cyclic tetrapyrrolic compounds which are derivatives of chlorophyll-a and -b. Seven of these compounds showed >50% phototoxicity at 5?μg?mL?1 while exhibiting minimal cytotoxicity in the dark, which is an important characteristic of an ideal photosensitizer.  相似文献   
107.
ABSTRACT: BACKGROUND: Pulmonary load of Legionella pneumophila in mice is normally determined by counting serial dilutions of bacterial colony forming units (CFU) on agar plates. This process is often tedious and time consuming. We describe a novel, rapid and versatile flow cytometric method that detects bacteria phagocytosed by neutrophils. FINDINGS: Mice were infected with L. pneumophila via intratracheal or intranasal administration. At various times after bacteria inoculation, mouse lungs were harvested and analysed concurrently for bacterial load by colony counting and flow cytometry analysis. The number of L. pneumophila-containing neutrophils correlated strongly with CFU obtained by bacteriological culture. CONCLUSIONS: This technique can be utilised to determine pulmonary bacterial load and may be used in conjunction with other flow cytometric based analyses of the resulting immune response.  相似文献   
108.
Miller KI  Qing C  Sze DM  Neilan BA 《PloS one》2012,7(5):e35953
Traditional Chinese medicine encompasses a rich empirical knowledge of the use of plants for the treatment of disease. In addition, the microorganisms associated with medicinal plants are also of interest as the producers of the compounds responsible for the observed plant bioactivity. The present study has pioneered the use of genetic screening to assess the potential of endophytes to synthesize bioactive compounds, as indicated by the presence of non-ribosomal peptide synthetase (NRPS) and polyketide synthase (PKS) genes. The total DNA extracts of 30 traditional Chinese herbs, were screened for functional genes involved in the biosynthesis of bioactive compounds. The four PCR screens were successful in targeting four bacterial PKS, six bacterial NRPS, ten fungal PKS and three fungal NRPS gene fragments. Analysis of the detected endophyte gene fragments afforded consideration of the possible bioactivity of the natural products produced by endophytes in medicinal herbs. This investigation describes a rapid method for the initial screening of medicinal herbs and has highlighted a subset of those plants that host endophytes with biosynthetic potential. These selected plants can be the focus of more comprehensive endophyte isolation and natural product studies.  相似文献   
109.
Glioblastoma multiforme (GBM) is a heterogeneous disease despite its seemingly uniform pathology. Deconvolution of The Cancer Genome Atlas''s GBM gene expression data has unveiled the existence of distinct gene expression signature underlying discrete GBM subtypes. Recent conflicting findings proposed that microRNA (miRNA)-10b exclusively regulates glioma growth or invasion but not both. We showed that silencing of miRNA-10b by baculoviral decoy vectors in a glioma cell line resembling the mesenchymal subtype of GBM reduces its growth, invasion and angiogenesis while promoting apoptosis in vitro. In an orthotopic human glioma mouse model, inhibition of miRNA-10b diminishes the invasiveness, angiogenicity and growth of the mesenchymal subtype-like glioma cells in the brain and significantly prolonged survival of glioma-bearing mice. We demonstrated that the pleiotropic nature of miRNA-10b was due to its suppression of multiple tumor suppressors, including TP53, FOXO3, CYLD, PAX6, PTCH1, HOXD10 and NOTCH1. In particular, siRNA-mediated knockdown experiments identified TP53, PAX6, NOTCH1 and HOXD10 as invasion regulatory genes in our mesenchymal subtype-like glioma cells. By interrogating the REMBRANDT, we noted that dysregulation of many direct targets of miRNA-10b was associated with significantly poorer patient survival. Thus, our study uncovers a novel role for miRNA-10b in regulating angiogenesis and suggests that miRNA-10b may be a pleiotropic regulator of gliomagenesis.  相似文献   
110.
Ribosome-inactivating proteins (RIPs) inactivate prokaryotic or eukaryotic ribosomes by removing a single adenine in the large ribosomal RNA. Here we show maize RIP (MOD), an atypical RIP with an internal inactivation loop, interacts with the ribosomal stalk protein P2 via Lys158–Lys161, which is located in the N-terminal domain and at the base of its internal loop. Due to subtle differences in the structure of maize RIP, hydrophobic interaction with the ‘FGLFD’ motif of P2 is not as evidenced in MOD-P2 interaction. As a result, interaction of P2 with MOD was weaker than those with trichosanthin and shiga toxin A as reflected by the dissociation constants (KD) of their interaction, which are 1037.50±65.75 µM, 611.70±28.13 µM and 194.84±9.47 µM respectively.Despite MOD and TCS target at the same ribosomal protein P2, MOD was found 48 and 10 folds less potent than trichosanthin in ribosome depurination and cytotoxicity to 293T cells respectively, implicating the strength of interaction between RIPs and ribosomal proteins is important for the biological activity of RIPs. Our work illustrates the flexibility on the docking of RIPs on ribosomal proteins for targeting the sarcin-ricin loop and the importance of protein-protein interaction for ribosome-inactivating activity.  相似文献   
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