胶质瘤患者血浆miR-21的表达水平及意义

目的:研究脑胶质瘤患者血浆中miR-21的水平,并评价其作为临床诊断标志物的可能性。方法:收集临床确诊的胶质瘤患者和健康对照人群的血浆标本,常规方法提取血浆中RNA,采用茎环结构的引物将其逆转录成cDNA,实时定量PCR的方法分别检测miR-21在胶质瘤患者和健康对照人群中的水平,根据ROC分析评价miR-21作为诊断标志物的可能性。结果:分别收集了胶质瘤患者和健康对照人群血浆标本52例和43例,实时定量PCR结果显示,相对于健康对照人群,miR-21在胶质瘤患者血浆中呈高水平状态。ROC分析说明血浆miR-21水平作为诊断胶质瘤标志物具有较高的灵敏度和特异度。结论:血浆miR-21水平具有作为胶质瘤诊断的生物标志物的潜能。     

The weakest link: sensitivity to climate extremes across life stages of marine invertebrates

Predicting the effects of climate change on Earth's biota becomes even more challenging when acknowledging that most species have life cycles consisting of multiple stages, each of which may respond differently to extreme environmental conditions. There is currently no clear consensus regarding which stages are most susceptible to increasing environmental stress, or ‘climate extremes’. We used a meta‐analytic approach to quantify variation in responses to environmental stress across multiple life stages of marine invertebrates. We identified 287 experiments in 29 papers which examined the lethal thresholds of multiple life stages (embryo, larva, juvenile and adult) of both holoplanktonic and meroplanktonic marine invertebrates subjected to the same experimental conditions of warming, acidification and hypoxia stress. Most studies considered short acute exposure to stressors. We calculated effect sizes (log response ratio) for each life stage (unpaired analysis) and the difference in effect sizes between stages of each species (paired analysis) included in each experiment. In the unpaired analysis, all significant responses were negative, indicating that warming, acidification and hypoxia tended to increase mortality. Furthermore, embryos, larvae and juveniles were more negatively affected by warming than adults. The paired analysis revealed that, when subjected to the same experimental conditions, younger life stages were more negatively affected by warming than older life stages, specifically among pairings of adults versus juveniles and larvae versus embryos. Although responses to warming are well documented, few studies of the effects of acidification and hypoxia met the criteria for inclusion in our analyses. Our results suggest that while most life stages will be negatively affected by climate change, younger stages of marine invertebrates are more sensitive to extreme heating events.     

Combined analysis of RNA‐sequence and microarray data reveals effective metabolism‐based prognostic signature for neuroblastoma

The relationship between metabolism reprogramming and neuroblastoma (NB) is largely unknown. In this study, one RNA‐sequence data set (n = 153) was used as discovery cohort and two microarray data sets (n = 498 and n = 223) were used as validation cohorts. Differentially expressed metabolic genes were identified by comparing stage 4s and stage 4 NBs. Twelve metabolic genes were selected by LASSO regression analysis and integrated into the prognostic signature. The metabolic gene signature successfully stratifies NB patients into two risk groups and performs well in predicting survival of NB patients. The prognostic value of the metabolic gene signature is also independent with other clinical risk factors. Nine metabolism‐related long non‐coding RNAs (lncRNAs) were also identified and integrated into the metabolism‐related lncRNA signature. The lncRNA signature also performs well in predicting survival of NB patients. These results suggest that the metabolic signatures have the potential to be used for risk stratification of NB. Gene set enrichment analysis (GSEA) reveals that multiple metabolic processes (including oxidative phosphorylation and tricarboxylic acid cycle, both of which are emerging targets for cancer therapy) are enriched in the high‐risk NB group, and no metabolic process is enriched in the low‐risk NB group. This result indicates that metabolism reprogramming is associated with the progression of NB and targeting certain metabolic pathways might be a promising therapy for NB.     

Downstream displacement of post‐emergent brown trout: effects of development stage and water velocity

Brown trout Salmo trutta were introduced at hatching into distinct sections of two parallel artificial channels, one with a constant low velocity (control) and one with velocity changes (experimental), at such times as to produce 12, 3 and 0 day old fish (age after emergences) when the velocity was changed in the experimental channel. This experimental design was repeated in 2002 and 2003 at comparable dates. Young brown trout were sensitive to an increased water velocity for 5 to 6 days after emergence. Water velocity modified the displacement patterns qualitatively but not quantitatively. Eighty per cent of fish moved downstream at all water velocities. Velocity changes, however, advanced the time by which 80% of the fish had displaced downstream.     

冬麦春播小麦穗分化阶段对低温胁迫的响应及耐寒性

以长江中下游地区引进的10个冬小麦品种为材料,在忻定盆地春播条件下,于2013-2014年研究了低温胁迫对冬小麦穗分化阶段光合作用、渗透调节物质及膜系统产生的影响,并对其抗寒性能进行综合评价.结果表明:在低温胁迫下,不同品种小麦叶片的离子渗漏率、可溶性糖和可溶性蛋白质含量均不同程度地升高,总叶绿素含量明显下降.通过主成分分析和抗寒性度量值(D值)排序,不同品种冬小麦幼穗分化期间的抗寒性为:渝麦10、扬麦20、云麦42的抗寒性较差;扬麦13、渝麦12、宁麦13的抗寒性较强且年际稳定性好,D值分别为0.665 ～0.659、0.493～0.495、0.471 ～0.583;而作为对照的宁2038、新春30分别为0.368～0.397、0.328～0.330.扬麦13、渝麦12、宁麦13的两年籽粒产量显著高于其他品种,可作为忻定盆地的引种材料.     

Pine sawfly Gilpinia albiclavata sp. nov. (Hymenoptera: Diprionidae) infesting Pinus pumila in the Japanese Alps

Gilpinia albiclavata Hara, sp. nov. is described from Honshu, Japan. Larvae feed on needles of Pinus pumila (Pinaceae). Since 2001, severe infestations of the sawfly have been often observed in the Japanese Alps. Notes on the immature stages and the life history are presented.     

Seasonal weather patterns drive population vital rates and persistence in a stream fish

Climate change affects seasonal weather patterns, but little is known about the relative importance of seasonal weather patterns on animal population vital rates. Even when such information exists, data are typically only available from intensive fieldwork (e.g., mark–recapture studies) at a limited spatial extent. Here, we investigated effects of seasonal air temperature and precipitation (fall, winter, and spring) on survival and recruitment of brook trout (Salvelinus fontinalis) at a broad spatial scale using a novel stage‐structured population model. The data were a 15‐year record of brook trout abundance from 72 sites distributed across a 170‐km‐long mountain range in Shenandoah National Park, Virginia, USA. Population vital rates responded differently to weather and site‐specific conditions. Specifically, young‐of‐year survival was most strongly affected by spring temperature, adult survival by elevation and per‐capita recruitment by winter precipitation. Low fall precipitation and high winter precipitation, the latter of which is predicted to increase under climate change for the study region, had the strongest negative effects on trout populations. Simulations show that trout abundance could be greatly reduced under constant high winter precipitation, consistent with the expected effects of gravel‐scouring flows on eggs and newly hatched individuals. However, high‐elevation sites would be less vulnerable to local extinction because they supported higher adult survival. Furthermore, the majority of brook trout populations are projected to persist if high winter precipitation occurs only intermittently (≤3 of 5 years) due to density‐dependent recruitment. Variable drivers of vital rates should be commonly found in animal populations characterized by ontogenetic changes in habitat, and such stage‐structured effects may increase population persistence to changing climate by not affecting all life stages simultaneously. Yet, our results also demonstrate that weather patterns during seemingly less consequential seasons (e.g., winter precipitation) can have major impacts on animal population dynamics.     

Clinicopathological characteristics of androgen receptor splicing variant 7 (AR-V7) expression in patients with castration resistant prostate cancer: A systematic review and meta‐analysis

Background Studies have shown that AR-V7 may be correlated with the poor prognosis of castration resistant prostate cancer (CRPC), however, clinicopathological characteristics of AR-V7 have not been fully elucidated.ObjectiveThis study aimed at evaluating the clinicopathological features of AR-V7 in CRPC patients.Materials and methodsTo evaluate the clinicopathological features of AR-V7 in CRPC patients. A search of PubMed, Embase, and Web of Science was performed using the keywords prostate cancer, prostate tumor, prostate neoplasm, prostate carcinoma, AR-V7, AR3, androgen receptor splicing variant-7, or androgen receptor-3. Twenty-four trials published by February 2020 were included in this study.ResultsThe proportion of Gleason score ≥ 8 was found to be significantly higher in AR-V7-positive CRPC (69.5%) than negative (54.9%) (OR 1.68, 95% CI 1.25–2.25, p < 0.001), while the rates of T3/T4 stage (OR 1.16, 95% CI 0.60–2.24, p = 0.65) and N1 stage (OR 0.99, 95% CI 0.65–1.51, p = 0.96) were not statistically correlated with AR-V7 status. The AR-V7-positive patients exhibited a significantly higher proportion of any site metastasis (61.3% versus 35.0%; OR 2.19, 95% CI 1.57–3.05, p < 0.001) and bone metastasis (81.7% versus 69.0%; OR 1.97, 95% CI 1.44–2.69, p < 0.001), and a trend close to significance was expected in visceral metastasis (28.8% versus 22.1%; OR 1.29, 95% CI 0.96–1.74, p = 0.09). Incidences of pain in AR-V7-positive CRPC (54.6%) were significantly higher than in negative CRPC (28.1%; OR 4.23, 95% CI 2.52–7.10, p < 0.001), line with worse ECOG performance status (56.7% versus 35.0%, OR 2.18, 95% CI 1.51–3.16, P < 0.001). Limitations of the study include differences in sample sizes and designs, AR-V7 detection assays, as well as disease characteristics of the included studies.ConclusionsAR-V7 positivity is associated with a higher Gleason score, bone or any site metastasis, pain and worse ECOG performance scores in CRPC. However, it is not correlated with tumor stage or lymph node metastasis. More studies are needed to confirm these findings.     

Stage-structured ontogeny in resource populations generates non-additive stabilizing and de-stabilizing forces in populations and communities

Demographic heterogeneity influences how populations respond to density dependent intraspecific competition and trophic interactions. Distinct stages across an organism's development, or ontogeny, are an important example of demographic heterogeneity. In consumer populations, ontogenetic stage structure has been shown to produce categorical differences in population dynamics, community dynamics and even species coexistence compared to models lacking explicit ontogeny. The study of consumer–resource interactions must also consider the ontogenetic stage structure of the resource itself, particularly plants, given their fundamental role at the basis of terrestrial food webs. We incorporate distinct ontogenetic stages of plants into an adaptable multi-stage consumer–resource modeling framework that facilitates studying how stage specific consumers shape trophic dynamics at low trophic levels. We describe the role of density dependent demographic rates in mediating the dynamics of stage-structured plant populations. We then investigate how these demographic rates interact with consumer pressure to influence stability and coexistence in multiple stage-specific consumer–resource interactions. Results detail how density dependent effects across distinct ontogenetic stages in plant development produce non-additivity in the drivers of dynamic stability both in single populations and in consumer–resource settings, challenging the ubiquity of certain traditional ecological dynamic paradigms. We also find categorical differences in the population variability induced by herbivores consuming separate plant stages. Consumer–resource models, such as plant–herbivore interactions, often average out demographic heterogeneity in populations. Here, we show that explicitly including plant demographic heterogeneity through ontogeny yields distinct dynamic expectations for both plants and herbivores compared to traditional consumer–resource formulations. Our results indicate that efforts to understand the demographic effect of herbivores on plant populations may need to also consider the effects of plant demographics on herbivores and the reciprocal relationship between them.