Photoluminescent Gold Nanoclusters as Sensing Probes for Uropathogenic Escherichia coli

Glycan-bound nanoprobes have been demonstrated as suitable sensing probes for bacteria containing glycan binding sites. In this study, we demonstrated a facile approach for generating glycan-bound gold nanoclusters (AuNCs). The generated AuNCs were used as sensing probes for corresponding target bacteria. Mannose-capped AuNCs (AuNCs@Mann) were generated and used as the model sensors for target bacteria. A one-step synthesis approach was employed to generate AuNCs@Mann. In this approach, an aqueous solution of tetrachloroauric acid and mannoside that functionized with a thiol group (Mann-SH) was stirred at room temperature for 48 h. The mannoside functions as reducing and capping agent. The size of the generated AuNCs@Mann is 1.95±0.27 nm, whereas the AuNCs with red photoluminescence have a maximum emission wavelength of ∼630 nm (λ_excitation = 375 nm). The synthesis of the AuNCs@Mann was accelerated by microwave heating, which enabled the synthesis of the AuNCs@Mann to complete within 1 h. The generated AuNCs@Mann are capable of selectively binding to the urinary tract infection isolate Escherichia coli J96 containing the mannose binding protein FimH expressed on the type 1 pili. On the basis of the naked eye observation, the limit of detection of the sensing approach is as low as ∼2×10⁶ cells/mL.     

Long‐term patterns of invertebrate abundance and relationships to environmental factors in arid Australia

Resource pulses are a key feature of semi‐arid and arid ecosystems and are generally triggered by rainfall. While rainfall is an acknowledged driver of the abundance and distribution of larger animals, little is known about how invertebrate communities respond to rain events or to vegetative productivity. Here we investigate Ordinal‐level patterns and drivers of ground‐dwelling invertebrate abundance across 6 years of sampling in the Simpson Desert, central Australia. Between February 1999 and February 2005, a total of 174 381 invertebrates were sampled from 32 Orders. Ants were the most abundant taxon, comprising 83% of all invertebrates captured, while Collembola at 10.3% of total captures were a distant second over this period. Temporal patterns of the six invertebrate taxa specifically analysed (Acarina, ants, Araneae, Coleoptera, Collembola and Thysanura) were dynamic over the sampling period, and patterns of abundance were taxon‐specific. Analyses indicate that all six taxa showed a positive relationship with the cover of non‐Triodia vegetation. Other indicators of vegetative productivity (seeding and flowering) also showed positive relationships with certain taxa. Although the influence of rainfall was taxon‐dependent, no taxon was affected by short‐term rainfall (up to 18 days prior to survey). The abundance of Acarina, ants, and Coleoptera increased with greater long‐term rainfall (up to 18 months prior to survey), whilst Araneae showed the opposite effect. Temperature and dune zone (dune crest vs. swale) also had taxon‐specific effects. These results show that invertebrates in arid ecosystems are influenced by a variety of abiotic factors, at multiple scales, and that responses to rainfall are not as strong or as predictable as those seen for other taxa. Our results highlight the diversity of invertebrates in our study region and emphasize the need for targeted long‐term sampling to enhance our understanding of the ecology of these taxa and the role they play in arid ecosystems.     

Effects of inhaled corticosteroids on sputum cell counts in stable chronic obstructive pulmonary disease: a systematic review and a meta-analysis

Background

Whether inhaled corticosteroids suppress airway inflammation in chronic obstructive pulmonary disease (COPD) remains controversial. We sought to determine the effects of inhaled corticosteroids on sputum indices of inflammation in stable COPD.

Methods

We searched MEDLINE, EMBASE, CINAHL, and the Cochrane Databases for randomized, controlled clinical trials that used induced sputum to evaluate the effect of inhaled corticosteroids in stable COPD. For each chosen study, we calculated the mean differences in the concentrations of sputum cells before and after treatment in both intervention and control groups. These values were then converted into standardized mean differences to accommodate the differences in patient selection, clinical treatment, and biochemical procedures that were employed across original studies. If significant heterogeneity was present (p < 0.10), then a random effects model was used to pool the original data. In the absence of significant heterogeneity, a fixed effects model was used.

Results

We identified six original studies that met the inclusion criteria (N = 162 participants). In studies with higher cumulative dose (≥ 60 mg) or longer duration of therapy (≥ 6 weeks), inhaled corticosteroids were uniformly effective in reducing the total cell, neutrophil, and lymphocyte counts. In contrast, studies with lower cumulative dose (< 60 mg) or shorter duration of therapy (< 6 weeks) did not demonstrate a favorable effect of inhaled corticosteroids on these sputum indices.

Conclusions

Our study suggests that prolonged therapy with inhaled corticosteroids is effective in reducing airway inflammation in stable COPD.     

三七总皂甙对博莱霉素所致小鼠肺纤维化的干预作用

目的:观察三七总皂甙(PNS)对实验性小鼠肺纤维化的干预作用。方法:小鼠随机分为正常对照组、模型对照组、醋酸泼尼松组和PNS大、中、小剂量组。通过气管内注入博莱霉素(BLM)复制小鼠肺纤维化模型,于造模后第2天各治疗组开始给药,于给药后第7、14、28 d处死部分小鼠,取肺组织,行HE染色,并测定肺组织中羟脯氨酸(HYP)含量。结果PNS能减少实验性肺纤维化小鼠肺组织中胶原沉积及降低肺系数(P<0.05,P<0.01),减轻肺部的病理损害(P<0.05,P<0.01)。结论:PNS对BLM诱导产生的小鼠肺纤维化有一定的抑制作用。     

Integrating Circadian Activity and Gene Expression Profiles to Predict Chronotoxicity of Drosophila suzukii Response to Insecticides

Native to Southeast Asia, Drosophila suzukii (Matsumura) is a recent invader that infests intact ripe and ripening fruit, leading to significant crop losses in the U.S., Canada, and Europe. Since current D. suzukii management strategies rely heavily on insecticide usage and insecticide detoxification gene expression is under circadian regulation in the closely related Drosophila melanogaster, we set out to determine if integrative analysis of daily activity patterns and detoxification gene expression can predict chronotoxicity of D. suzukii to insecticides. Locomotor assays were performed under conditions that approximate a typical summer or winter day in Watsonville, California, where D. suzukii was first detected in North America. As expected, daily activity patterns of D. suzukii appeared quite different between ‘summer’ and ‘winter’ conditions due to differences in photoperiod and temperature. In the ‘summer’, D. suzukii assumed a more bimodal activity pattern, with maximum activity occurring at dawn and dusk. In the ‘winter’, activity was unimodal and restricted to the warmest part of the circadian cycle. Expression analysis of six detoxification genes and acute contact bioassays were performed at multiple circadian times, but only in conditions approximating Watsonville summer, the cropping season, when most insecticide applications occur. Five of the genes tested exhibited rhythmic expression, with the majority showing peak expression at dawn (ZT0, 6am). We observed significant differences in the chronotoxicity of D. suzukii towards malathion, with highest susceptibility at ZT0 (6am), corresponding to peak expression of cytochrome P450s that may be involved in bioactivation of malathion. High activity levels were not found to correlate with high insecticide susceptibility as initially hypothesized. Chronobiology and chronotoxicity of D. suzukii provide valuable insights for monitoring and control efforts, because insect activity as well as insecticide timing and efficacy are crucial considerations for pest management. However, field research is necessary for extrapolation to agricultural settings.     

Changes in somatostatin-like immunoreactivity in lungs from perinatal guinea pigs and the effects of somatostatin-14 on lung liquid production.

Somatostatin-like immunoreactivity was measured by radioimmunoassay with a monoclonal antibody in lungs from perinatal guinea pigs (62 +/- 2 days of gestation). Fetuses delivered by Caesarean section and dissected before breathing showed 4748 +/- 758 pg/lung (n = 25). Fetuses allowed to breathe (neonates) showed marked increases in activity: 7629 +/- 1355 pg/lung (n = 12) after breathing 30 seconds, and 10729 +/- 1064 pg/lung (n = 6) after breathing 3 minutes (2.3-fold increase, P < 0.005). Values then declined (5203 +/- 1050 pg/lung (n = 9) at 30 minutes; 1458 +/- 105 pg/lung (n = 4) at 60 minutes). Changes were similar in pg/g wet tissue. HPLC characterized the immunoreactive peptides as somatostatin-14 (SS-14) and somatostatin-28 (SS-28) in both fetuses and neonates (n = 11). SS-28 made up only 13.7 +/- 1.7% of the activity; this percentage did not change with breathing. The effects of synthetic SS-14 on lung liquid production were investigated in in vitro lungs from 42 fetal guinea pigs. All 21 preparations immersed in 10(-5)-10(-7) M SS-14 during the middle hour of 3 h incubations reduced production, often approaching zero after treatment (rates, ml/kg body weight per h, succeeding hours: 10(-5) M (n = 9), 3.09 +/- 0.68, 0.93 +/- 0.39, -0.05 +/- 0.60 (fall significant during and after treatment, P < 0.025-0.005); 10(-6) M (n = 6), 3.06 +/- 0.68, 1.29 +/- 0.58, 0.36 +/- 0.38 (P < 0.05-0.005); 10(-7) M (n = 6), 1.96 +/- 0.66, 1.11 +/- 0.34, 0.64 +/- 0.28 (P < 0.05-0.025).(ABSTRACT TRUNCATED AT 250 WORDS)     

Arabidopsis COP8, COP10, and COP11 genes are involved in repression of photomorphogenic development in darkness.

Wild-type Arabidopsis seedlings are capable of following two developmental programs: photomorphogenesis in the light and skotomorphogenesis in darkness. Screening of Arabidopsis mutants for constitutive photomorphogenic development in darkness resulted in the identification of three new loci designated COP8, COP10, and COP11. Detailed examination of the temporal morphological and cellular differentiation patterns of wild-type and mutant seedlings revealed that in darkness, seedlings homozygous for recessive mutations in COP8, COP10, and COP11 failed to suppress the photomorphogenic developmental pathway and were unable to initiate skotomorphogenesis. As a consequence, the mutant seedlings grown in the dark had short hypocotyls and open and expanded cotyledons, with characteristic photomorphogenic cellular differentiation patterns and elevated levels of light-inducible gene expression. In addition, plastids of dark-grown mutants were defective in etioplast differentiation. Similar to cop1 and cop9, and in contrast to det1 (deetiolated), these new mutants lacked dark-adaptive change of light-regulated gene expression and retained normal phytochrome control of seed germination. Epistatic analyses with the long hypocotyl hy1, hy2, hy3, hy4, and hy5 mutations suggested that these three loci, similar to COP1 and COP9, act downstream of both phytochromes and a blue light receptor, and probably HY5 as well. Further, cop8-1, cop10-1, and cop11-1 mutants accumulated higher levels of COP1, a feature similar to the cop9-1 mutant. These results suggested that COP8, COP10, and COP11, together with COP1, COP9, and DET1, function to suppress the photomorphogenic developmental program and to promote skotomorphogenesis in darkness. The identical phenotypes resulting from mutations in COP8, COP9, COP10, and COP11 imply that their encoded products function in close proximity, possibly with some of them as a complex, in the same signal transduction pathway.