Abundance matters: role of albumin in diabetes,a proteomics perspective

Introduction: Human serum albumin (HSA) is a multifaceted protein with vital physiological functions. It is the most abundant plasma protein with inherent capability to bind to diverse ligands, and thus susceptible to various post-translational modifications (PTMs) which alter its structure and functions. One such PTM is glycation, a non-enzymatic reaction between reducing sugar and protein leading to formation of heterogeneous advanced glycation end products (AGEs). Glycated albumin (GA) concentration increases significantly in diabetes and is implicated in development of secondary complications.

Areas covered: In this review, we discuss in depth, formation of GA and its consequences, approaches used for characterization and quantification of GA, milestones in GA proteomics, clinical relevance of GA as a biomarker, significance of maintaining abundant levels of albumin and future perspectives.

Expert commentary: Elevated GA levels are associated with development of insulin resistance as well as secondary complications, in healthy and diabetic individuals respectively. Mass spectrometry (MS) based approaches aid in precise characterization and quantification of GA including early and advanced glycated peptides, which can be useful in prediction of the disease status. Thus GA has evolved to be one of the best candidates in the pursuit of diagnostic markers for prediction of prediabetes and diabetic complications.     

Variations of rest-activity rhythm and sleep-wake in schizophrenic patients versus healthy subjects: An actigraphic comparative study

The objective of the present study was to compare the pattern of motor activity in unmedicated schizophrenia patients and healthy subjects, and to examine whether the pattern was affected by treatment with typical and atypical antipsychotics. Twenty unmedicated schizophrenic patients wore a wrist actigraph for five days. The actigraph recorded activity levels in one-minute epochs. Patients' pattern of activity was compared with that of healthy subjects. Patients were randomly assigned to treatment with low-dose haloperidol or risperidone. The impact of treatment on the pattern of activity was examined. Compared to controls, untreated patients showed a diminished mean activity count during morning, early and late night periods. Treatment with haloperidol or risperidone at effective doses showed a significant effect on activity level, being more prominent with haloperidol. The results suggest that unmedicated schizophrenic patients exhibit abnormally low levels of motor activity as measured with an objective activity meter. This persists after antipsychotic treatment even though symptoms improve. Future studies should clarify whether motor disturbances are a primary effect of the illness, or related to the illness-related lifestyle.     

大型水母声学观测与评估技术研究进展

20世纪末以来,世界多个海域频繁出现大型水母暴发现象,对海洋生态系统、海洋渔业、沿海工业和滨海旅游业带来了巨大的灾难。为了研究大型水母生态习性,进而揭示其暴发机理并进行灾害的预警防治,近些年来国内外学者开展了大量的采用网具、目视、水下摄像、声学技术、航空影像等多种手段的大型水母监测调查工作,其中使用声学技术对大型水母进行资源评估和行为跟踪目前在欧美、日本、韩国等渔业发达国家已经开展了相关应用,在资源评估、运动学规律等研究中展现出较好的观测效果和应用潜力。目前我国在大型水母声学观测研究应用领域鲜有文献报道,通过介绍国际上利用声学技术对大型水母进行资源调查与评估、空间分布监测、运动规律等研究成果,为今后我国开展大型水母声学调查研究提供理论基础和科学依据。通过本文的分析,建议可以借鉴国际上采用科学鱼探仪、高分辨率成像声呐、声学信标等方法对大型水母进行监测调查和资源评估的研究成果,结合实际情况将声学技术逐步研究并应用到我国大型水母资源调查与评估、自然生态习性研究、重点水域大型水母动态监测预警中去,完善我国大型水母监测调查体系。     

Optimal gillnet sampling design for the estimation of fish community indicators in heterogeneous freshwater ecosystems

Monitoring of biota in heterogeneous ecosystems requires sampling in different habitats and across environmental gradients. The resulting multivariate community data are typically aggregated into one or several indicator values for the entire ecosystem, but the relationship between the robustness of such indicators and sampling effort, including the identification of minimum acceptable sampling designs, is not fully understood.We address this issue for multi-mesh gillnet sampling of freshwater fish communities in deep-valley reservoirs, using data from 29 detailed annual surveys in eight reservoirs in the Czech Republic that account for the inherent longitudinal and depth gradients and the qualitatively different benthic and pelagic habitats. We evaluate the performance of eight sampling scenarios, created by variously reducing the full dataset. To this end, we use 31 fish-based, community-, size- and species-level indicators calculated separately for benthic and pelagic habitats, and fit the relationships between the indicator values based on the reduced and full sampling design using Bayesian generalized linear models.The ability of reduced data to estimate the “true” indicator value across the entire dataset, expressed as the adjusted R² value of the best model for the given indicator, increased with sampling effort. However, the relationships differed between indicators: R² values were higher for abundance-based than for biomass-based indicators. We identified three suitable reduced sampling designs: (1) sampling the entire longitudinal profile in the epilimnion, yielding on average the highest R² values (0.97), (2) same as before but limited to one sampling layer closest to the surface (R² = 0.91), and (3) sampling all depth strata at the farthest points of the longitudinal gradient (i.e., dam and tributary, R² = 0.83). These results demonstrate that, in order to obtain robust estimates of fish community indicators, current gillnet sampling protocols can be optimized to reduce effort and minimize unwanted fish mortality.     

絮凝颗粒粒度分布对自絮凝酵母SPSC01乙醇耐受能力的影响

利用激光聚焦反射式颗粒测量系统, 通过调节不同的搅拌速率, 得到了分批补料培养条件下粒度分布不同的四个絮凝酵母SPSC01颗粒群体, 进而对絮凝颗粒群体分布对乙醇耐受性进行了系统研究。经过6 h、20%乙醇的冲击, 颗粒粒度为100、200、300和400 mm的自絮凝酵母SPSC01的存活率分别为3.5%、26.7%、48.8%和37.6%。这表明不同粒度分布的絮凝颗粒群体乙醇耐受性具有明显差别, 在一定粒度范围内乙醇耐受性达到最高, 乙醇耐受性最高的酵母群体的乙醇得率系数85.5%, 比乙醇耐性最低的颗粒群体提高了7.2%。粒度为100、200和300 mm的自絮凝酵母颗粒群体总麦角固醇、游离麦角固醇及海藻糖含量与粒度大小成正相关, 但在粒度为400 mm的絮凝颗粒群体中总麦角固醇、游离麦角固醇及海藻糖含量呈下降趋势, 与其乙醇耐性低于300 mm絮凝颗粒的结果相一致。对细胞膜透性的研究表明, 颗粒粒度为300 mm的絮凝酵母颗粒细胞膜通透性(P′)最低, 分别仅为颗粒粒度为100 mm和200 mm颗粒群体的43%和52%, 表明粒度分布不同的絮凝颗粒群体乙醇耐性的差别与细胞膜透性密切相关。     

Bring your own camera to the trap: An inexpensive,versatile, and portable triggering system tested on wild hummingbirds

The study of animals in the wild offers opportunities to collect relevant information on their natural behavior and abilities to perform ecologically relevant tasks. However, it also poses challenges such as accounting for observer effects, human sensory limitations, and the time intensiveness of this type of research. To meet these challenges, field biologists have deployed camera traps to remotely record animal behavior in the wild. Despite their ubiquity in research, many commercial camera traps have limitations, and the species and behavior of interest may present unique challenges. For example, no camera traps support high‐speed video recording. We present a new and inexpensive camera trap system that increases versatility by separating the camera from the triggering mechanism. Our system design can pair with virtually any camera and allows for independent positioning of a variety of sensors, all while being low‐cost, lightweight, weatherproof, and energy efficient. By using our specialized trigger and customized sensor configurations, many limitations of commercial camera traps can be overcome. We use this system to study hummingbird feeding behavior using high‐speed video cameras to capture fast movements and multiple sensors placed away from the camera to detect small body sizes. While designed for hummingbirds, our application can be extended to any system where specialized camera or sensor features are required, or commercial camera traps are cost‐prohibitive, allowing camera trap use in more research avenues and by more researchers.     

Development of AC microelectrophoresis for rapid protein affinity evaluation

We have developed a new method for evaluating the affinity interactions between two different proteins by applying an alternating current (AC) voltage to a micro-flow channel. An AC voltage was applied to the protein-modified microspheres in the micro-flow channel, which resulted in the oscillation of the microspheres owing to their surface charges. The oscillation amplitude showed a linear relationship with the charge density of the microspheres. As an example for protein affinity measurement, the amplitude changes of a profilin-modified microsphere were measured by the addition of actin. In the same electrical condition, the oscillation amplitude of the profilin-modified microsphere increased by ≈175% by binding with actin. Similar results in the principle were obtained for the affinity interaction between biotin and streptavidin. The results showed that the higher the charge density of the microspheres induced by binding with different proteins, the higher the oscillation amplitude of the microspheres, thus, suggesting a possible application of the micro-flow channel and AC voltage on the protein property study, as well as on the biosensor application using the oscillation amplitude changes.     

Endoparasites observed within invertebrates used as live food items for captive wild birds: Overview and potential risks

To monitor and evaluate potential risks to birds’ health, invertebrate species that have been used as live food items had their body contents searched for endoparasites. The contents of approximately 10,000 invertebrates were analyzed. A principal component analysis was performed to study the relationship between the presence/absence of endoparasites and the characteristics of the invertebrates. In most of them, including the species preferred by birds such as caterpillars, waxworms, mealworms, most grasshoppers, and spiders, no organism was identified. Such findings suggest a low potential for parasite transmission associated with its consumption by birds. Although they had unknown or even unlikely implications for the birds’ health, gregarines, oxyurides Leidynema sp., and digenetic trematodes Monolecithotrema sp. were found in samples from woodlice, cockroaches, and centipedes, respectively. The only avian parasites observed in this study were Heterakis gallinarum in samples from earthworms and Acuaria spiralis from woodlice. Suggestively, soil invertebrates showed a higher prevalence of endoparasites and may represent a higher potential risk in comparison to the other categories of invertebrates sampled herein. Detritivory and collected origin were also explanatory variables related to the presence of endoparasites in the current study.     

Individual and simultaneous treatment with antipsychotic aripiprazole and antidepressant trazodone inhibit sterol biosynthesis in the adult brain

Polypharmacy, or the simultaneous use of multiple drugs to treat a single patient, is a common practice in psychiatry. Unfortunately, data on the health effects of commonly used combinations of medications are very limited. In this study, we therefore investigated the effects and interactions between two commonly prescribed psychotropic medications with sterol inhibiting side effects, trazodone (TRZ), an antidepressant, and aripiprazole (ARI), an antipsychotic. In vitro cell culture experiments revealed that both medications alone disrupted neuronal and astroglial sterol biosynthesis in dose-dependent manners. Furthermore, when ARI and TRZ were combined, exposure resulted in an additive 7-dehydrocholesterol (7-DHC) increase, as well as desmosterol (DES) and cholesterol decreases in both cell types. In adult mice, at baseline, we found that the three investigated sterols showed significant differences in distribution across the eight assessed brain regions. Furthermore, experimental mice treated with ARI or TRZ, or a combination of both medications for 8 days, showed strong sterol disruption across all brain regions. We show ARI or TRZ alone elevated 7-DHC and decreased DES levels in all brain regions, but with regional differences. However, the combined utilization of these two medications for 8 days did not lead to additive changes in sterol disturbances. Based on the complex roles of 7-DHC derived oxysterols, we conclude that individual and potentially simultaneous use of medications with sterol biosynthesis-inhibiting properties might have undesired side effects on the adult brain, with as yet unknown long-term consequences on mental or physical health.     

Response of female melon fly, Bactrocera cucurbitae, to host-associated visual and olfactory stimuli

In a series of studies conducted in Hawaii under seminatural conditions, we quantified the response of sexually mature, host‐seeking female melon flies, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), to different types of visual and chemical host‐associated stimuli with the main aim of developing a monitoring device for females. Experiments were conducted using Tangletrap‐coated fruit mimics of either spherical (8 cm diameter) or cylindrical (4.3 cm diameter; 15 cm length) shapes coated with different artificial color pigments both at the ground level and at the tree‐canopy level so as to take into account the foraging behavior of adult melon flies. Females were particularly attracted to objects of spherical shape colored either yellow, white, or orange; these three pigments offered the highest reflectance values. Cucumber (Cucumis sativus L.) (Cucurbitaceae) odor was more attractive to females than odors of three other cultivated host fruit [zucchini, Cucurbita pepo L. var. medullosa Alef. (Cucurbitaceae); papaya, Carica papaya L. (Caricaceae); or tomato Solanum lycopersicum L. (Solanaceae)] or of ivy gourd [Coccinia grandis (L.) Voigt (Cucurbitaceae)], one of the major wild hosts of melon fly in Hawaii. A combination of both visual and olfactory stimuli was needed to elicit high levels of response compared to each stimulus offered alone. We discuss our results in relation to the potential implementation of improved female monitoring and/or attract‐and‐kill strategies for melon flies in Hawaii.