Avian Incubation Inhibits Growth and Diversification of Bacterial Assemblages on Eggs

Microbial infection is a critical source of mortality for early life stages of oviparous vertebrates, but parental defenses against infection are less well known. Avian incubation has been hypothesized to reduce the risk of trans-shell infection by limiting microbial growth of pathogenic bacteria on eggshells, while enhancing growth of commensal or beneficial bacteria that inhibit or competitively exclude pathogens. We tested this hypothesis by comparing bacterial assemblages on naturally incubated and experimentally unincubated eggs at laying and late incubation using a universal 16S rRNA microarray containing probes for over 8000 bacterial taxa. Before treatment, bacterial assemblages on individual eggs from both treatment groups were dissimilar to one another, as measured by clustering in non-metric dimensional scaling (NMDS) ordination space. After treatment, assemblages of unincubated eggs were similar to one another, but those of incubated eggs were not. Furthermore, assemblages of unincubated eggs were characterized by high abundance of six indicator species while incubated eggs had no indicator species. Bacterial taxon richness remained static on incubated eggs, but increased significantly on unincubated eggs, especially in several families of Gram-negative bacteria. The relative abundance of individual bacterial taxa did not change on incubated eggs, but that of 82 bacterial taxa, including some known to infect the interior of eggs, increased on unincubated eggs. Thus, incubation inhibits all of the relatively few bacteria that grow on eggshells, and does not appear to promote growth of any bacteria.     

孵化期遗鸥卵质量变化及卵参数测定

本研究在红碱淖湿地共收集遗鸥Larus relictus卵111枚,采用实测和公式计算的方法进行卵参数测定。结果表明,同窝卵各参数随产卵顺序依次减少(卵质量:1=59.31 g±3.86 g,2=56.59 g±3.67 g,3=54.99 g±3.96 g),其中第1枚卵质量与第2、3枚卵质量差异有统计学意义(P0.05)。这可能与自身能量储备有关,通过减轻卵质量和缩小卵大小,但又不影响卵孵化率,以达到亲鸟最大繁殖适合度的策略。遗鸥在孵化阶段卵质量损失9.50 g±1.45 g,损失率为15.82%±1.94%。孵化后3~5 d和雏鸟出壳前2 d卵质量损失出现明显峰值,整体上卵质量损失速度与胚胎发育速度一致。野外调查中,当能获得卵鲜质量时,用Paganelli公式计算;反之,用Narhshin公式计算。但2种方法计算结果与实测结果差异无统计学意义(P0.05)。总体上,在遗鸥卵参数测定中,Paganelli公式比Narushin公式更简便、快捷。     

Root Secretion of Defense-related Proteins Is Development-dependent and Correlated with Flowering Time

Proteins found in the root exudates are thought to play a role in the interactions between plants and soil organisms. To gain a better understanding of protein secretion by roots, we conducted a systematic proteomic analysis of the root exudates of Arabidopsis thaliana at different plant developmental stages. In total, we identified 111 proteins secreted by roots, the majority of which were exuded constitutively during all stages of development. However, defense-related proteins such as chitinases, glucanases, myrosinases, and others showed enhanced secretion during flowering. Defense-impaired mutants npr1-1 and NahG showed lower levels of secretion of defense proteins at flowering compared with the wild type. The flowering-defective mutants fca-1, stm-4, and co-1 showed almost undetectable levels of defense proteins in their root exudates at similar time points. In contrast, root secretions of defense-enhanced cpr5-2 mutants showed higher levels of defense proteins. The proteomics data were positively correlated with enzymatic activity assays for defense proteins and with in silico gene expression analysis of genes specifically expressed in roots of Arabidopsis. In conclusion, our results show a clear correlation between defense-related proteins secreted by roots and flowering time.     

Early Postnatal BMI Adaptation Is Regulated During a Fixed Time Period and Mainly Depends on Maternal BMI

In the present study, we investigated whether there are critical time periods which influence the course of BMI during the first 6 years of life. From 5,433 children who participated in preschool examinations those 212 children were selected who crossed the BMI percentiles as a result of an extreme postnatal BMI rise (from <10th to 90th percentile) or fall (from >90th to <10th percentile) or who have persistently low or high BMI both at birth and at the age of 6 years. Forty children with a BMI close to the 50th percentile both at birth and age 6 years were selected to serve as controls. The courses of weight and height during the first 6 years of age were assessed and BMI was calculated. To identify influences connected with BMI development, we investigated genetic, social, nutritional, and other factors proceeding from the mother during pregnancy. Finally completed data sets of 57 children were available. Our study shows that during two critical time periods a significant move toward low or high BMI takes place among the groups: in early infancy from ～0.5 to 1.5 years and again from 5 to 6 years. At the age of 1.5 years the final state of BMI is already fixed in all study groups. Mothers of overweight 6‐year‐old children are overweight, whereas mothers of underweight 6‐year‐old children have a below‐normal BMI. All other investigated factors only had a minor influence on postnatal BMI development. We conclude that postnatal BMI development follows a fixed genetic program and is mainly programmed by maternal metabolism.     

Adaptation of the Avian Egg to High Altitude

Theoretical predictions and experiments on eggs of domesticatedbirds indicate that the diffusion coefficient of gases is inverselyproportional to barometric pressure. Therefore potentially lethallosses of CO₂ and water vapor from eggs laid at high altitudemight result if the increased tendency of gases to diffuse atreduced barometric pressure were not counteracted in some manner.Limited data from two wild populations indicate that water lossfrom eggs is independent of altitude over a 3000 m elevationalgradient. Four different possibilities are discussed by whichcompensation for increased diffusion of water vapor might beachieved at high elevations 1) a reduction in eggshell conductance(GH₂O) 2) an increase in the initial water content of the eggs3) an increase in shell thickness, and 4) alteration of watervapor pressure in the nest microenvironment or incubation temperatureby variation in parental behavior. Mean GH₂O of eggs of twoprecocial and four altricial species breeding above 2800 m issignificantly reduced below values of related birds breedingat lower elevations, but no change in initial water contentor shell thickness has been observed in such eggs. Observationsof parental behavior in species breeding over wide elevationalgradients have not yet been made. Identification of the mechanismsby which eggshell structure is modified to achieve a reducedGH₂O the environmental cues used by females to determine theelevation of the breeding location and the rapidity with whichshell structuie can be modified awaits further research.     

罗哌卡因复合舒芬太尼在潜伏期分娩镇痛中的应用效果

目的:探讨罗哌卡因复合舒芬太尼在潜伏期分娩镇痛中的应用效果。方法:择取2015年1月~2016年1月我院收治的产妇102例,随机分为A、B、C组,各组34例,A组产妇宫口开至1 cm时采取罗哌卡因复合舒芬太尼硬膜外自控分娩镇痛,B组产妇宫口开至3 cm时采取罗哌卡因复合舒芬太尼硬膜外自控分娩镇痛,C组产妇未采取分娩镇痛,比较两组第一产程潜伏期、活跃期及第二产程持续时间及宫缩时视觉模拟评分(VAS)评分,比较各组产妇出血量、新生儿体质量及胎儿娩出后1 min、5 min Apgar评分,记录各组治疗30 d后不良反应。结果:A组、B组第一产程潜伏期持续时间明显较C组延长,活跃期持续时间较C组明显缩短,差异有统计学意义(P0.05);A组产妇宫颈口开至2 cm和cm时VAS评分低于B组和C组,差异有统计学意义(P0.05);A组、B组产妇在活跃期、第二产程时VAS评分低于C组,差异有统计学意义(P0.05);各组产妇出血量、新生儿体质量、Apgar评分比较均无统计学意义(P0.05);C组抑郁症发生率均高于较A组和B组,差异有统计学意义(P0.05)。结论:从产妇潜伏期开始应用罗哌卡因复合舒芬太尼进行分娩镇痛的效果较好,具有良好的应用价值。     

Acyl Chain Length of Phosphatidylserine Is Correlated with Plant Lifespan

Plant lifespan is affected by factors with genetic and environmental bases. The laws governing these two factors and how they affect plant lifespan are unclear. Here we show that the acyl chain length (ACL) of phosphatidylserine (PS) is correlated with plant lifespan. Among the detected eight head-group classes of membrane lipids with lipidomics based on triple quadrupole tandem mass spectrometry, the ACL of PS showed high diversity, in contrast to the ACLs of the other seven classes, which were highly conserved over all stages of development in all plant species and organs and under all conditions that we studied. Further investigation found that acyl chains of PS lengthened during development, senescence, and under environmental stresses and that increasing length was accelerated by promoted- senescence. The acyl chains of PS were limited to a certain carbon number and ceased to increase in length when plants were close to death. These findings suggest that the ACL of PS can count plant lifespan and could be a molecular scale ruler for measuring plant development and senescence.     

Mechanism of Cisplatin-Induced Cytotoxicity Is Correlated to Impaired Metabolism Due to Mitochondrial ROS Generation

The chemotherapeutic use of cisplatin is limited by its severe side effects. In this study, by conducting different omics data analyses, we demonstrated that cisplatin induces cell death in a proximal tubular cell line by suppressing glycolysis- and tricarboxylic acid (TCA)/mitochondria-related genes. Furthermore, analysis of the urine from cisplatin-treated rats revealed the lower expression levels of enzymes involved in glycolysis, TCA cycle, and genes related to mitochondrial stability and confirmed the cisplatin-related metabolic abnormalities. Additionally, an increase in the level of p53, which directly inhibits glycolysis, has been observed. Inhibition of p53 restored glycolysis and significantly reduced the rate of cell death at 24 h and 48 h due to p53 inhibition. The foremost reason of cisplatin-related cytotoxicity has been correlated to the generation of mitochondrial reactive oxygen species (ROS) that influence multiple pathways. Abnormalities in these pathways resulted in the collapse of mitochondrial energy production, which in turn sensitized the cells to death. The quenching of ROS led to the amelioration of the affected pathways. Considering these observations, it can be concluded that there is a significant correlation between cisplatin and metabolic dysfunctions involving mROS as the major player.     

孵育时间在二氧化钛选择性富集磷酸化肽中的影响

目的:旨在探索孵育时间在二氧化钛选择性富集磷酸化肽中的影响。方法:以大肠杆菌BL21(DE3)为材料,预实验确定二氧化钛磁珠与肽段之间的最适比例,之后在此比例下继续探究不同孵育时间条件下的富集效果,以观察孵育时间在二氧化钛富集体系中的影响。结果:预实验确定磁珠与肽段之间最适比例为3 :1,在此比例下发现随着孵育时间的增加其富集效率会逐渐降低,最后确定大肠杆菌中最适孵育时间为5min。结论:孵育时间在大肠杆菌二氧化钛富集体系中对富集效果有明显的影响,并且呈负相关。推测不同样品的最佳孵育时间与样品种属有关。     

Antimalarial Use of Malagasy Plants Is Poorly Correlated with Performance in Antimalarial Bioassays

Bioassay screening of plant extracts can identify unique lead compounds for drug development, but the “hit rate” from random screening is very low. Targeted screening of medicinal plants has been repeatedly reported to increase the percentage of samples displaying bioactivity. Contrarily, Maranz (2012) suggested that African antimalarial plants were unsuitable sources of antimalarial drugs because high prevalence of malaria would result in rapid evolution of resistance to active compounds that directly targeted the parasite. As malaria is highly prevalent in much of Madagascar, it was of interest to determine whether Malagasy antimalarial plants would outperform randomly selected plants in conventional antimalarial assays being conducted as part of a discovery program. Of 1294 plant samples screened for antimalarial activity, 39.6% had an IC₅₀ <50 μg/ml and 21.1% had an IC₅₀ <20 μg/ml (the minimum to qualify as a first-pass “hit”). Ethnobotanical uses were coded at both the generic and the species level, as neither samples nor use reports in literature were always identifiable to species level. The 526 samples belonging to genera having reported uses for malaria were slightly more likely than average to display activity (44.3% with IC₅₀ <50 μg/ml, p < .01; 23.2% with IC₅₀ <20 μg/ml). Of these, 67 samples from individual species with documented use were still more likely to be modestly active (49.3% with IC₅₀ <50 μg/ml), yet less likely to be highly active (17.9% with IC₅₀ <20 μg/ml). Thus, in this specific context, ethnobotanically directed screening would not have substantially improved screening efficiency and would have missed most of the potential hits.     

High YKL-40 Serum Concentration Is Correlated with Prognosis of Chinese Patients with Breast Cancer

This study aimed to investigate the association between serum YKL-40 and prognosis of breast cancer in a Chinese population. Expression of YKL-40 of 120 Chinese patients with breast cancer and 30 controls (benign breast lesions) was measured in tumor tissue by immunohistochemistry and in serum by ELISA. Differences in YKL-40 positivity grouped by specific patients’ characteristics were compared using Pearson Chi-square test for rates of intratumoral staining, one-way ANOVA with a Bonferroni post-hoc comparison, or two-sample t-test for mean YKL-40 serum concentrations. Factors associated with overall survival were identified by univariate and multivariate cox-regression analyses. YKL-40 was elevated in approximately 75% of Chinese patients with breast cancer. A significantly higher percentage of patients with YKL-40 positive tumors had larger tumor size, higher TNM stage, and/or lymph node metastasis. Significantly higher mean YKL-40 serum concentrations were observed in patient subgroups with invasive lobular carcinoma (P<0.0167), higher TNM stage (P<0.001), and positive lymph node metastasis (P<0.001). The estimated mean survival time of patients with YKL-40 positive tumors was significantly shorter than for patients with YKL-40 negative tumors (55.13 months vs 65.78 months, P = 0.017). Multivariable Cox-regression analysis identified a significant association of overall survival time with YKL-40 serum concentration. Patients with YKL-40 positive tumors had significantly shorter disease free survival times than those with YKL-40 negative tumors. We propose that the potential utility of YKL-40 intratumoral staining or serum concentration as a biomarker for breast cancer is greatest within 5 years of diagnosis.     

Helminth Induced Suppression of Macrophage Activation Is Correlated with Inhibition of Calcium Channel Activity

Helminth parasites cause persistent infections in humans and yet many infected individuals are asymptomatic. Neurocysticercosis (NCC), a disease of the central nervous system (CNS) caused by the cestode Taenia solium, has a long asymptomatic phase correlated with an absence of brain inflammation. However, the mechanisms of immune suppression remain poorly understood. Here we report that murine NCC displays a lack of cell surface maturation markers in infiltrating myeloid cells. Furthermore, soluble parasite ligands (PL) failed to induce maturation of macrophages, and inhibited TLR-induced inflammatory cytokine production. Importantly, PL treatment abolished both LPS and thapsigargin-induced store operated Ca²⁺ entry (SOCE). Moreover, electrophysiological recordings demonstrated PL-mediated inhibition of LPS or Tg-induced currents that were TRPC1-dependent. Concomitantly STIM1-TRPC1 complex was also impaired that was essential for SOCE and sustained Ca²⁺ entry. Likewise loss of SOCE due to PL further inhibited NFkB activation. Overall, our results indicate that the negative regulation of agonist induced Ca²⁺ signaling pathway by parasite ligands may be a novel immune suppressive mechanism to block the initiation of the inflammatory response associated with helminth infections.     

The First Occurrence in the Fossil Record of an Aquatic Avian Twig-Nest with Phoenicopteriformes Eggs: Evolutionary Implications

Background

We describe the first occurrence in the fossil record of an aquatic avian twig-nest with five eggs in situ (Early Miocene Tudela Formation, Ebro Basin, Spain). Extensive outcrops of this formation reveal autochthonous avian osteological and oological fossils that represent a single taxon identified as a basal phoenicopterid. Although the eggshell structure is definitively phoenicopterid, the characteristics of both the nest and the eggs are similar to those of modern grebes. These observations allow us to address the origin of the disparities between the sister taxa Podicipedidae and Phoenicopteridae crown clades, and traces the evolution of the nesting and reproductive environments for phoenicopteriforms.

Methodology/Principal Findings

Multi-disciplinary analyses performed on fossilized vegetation and eggshells from the eggs in the nest and its embedding sediments indicate that this new phoenicopterid thrived under a semi-arid climate in an oligohaline (seasonally mesohaline) shallow endorheic lacustine environment. High-end microcharacterizations including SEM, TEM, and EBSD techniques were pivotal to identifying these phoenicopterid eggshells. Anatomical comparisons of the fossil bones with those of Phoenicopteriformes and Podicipediformes crown clades and extinct palaelodids confirm that this avian fossil assemblage belongs to a new and basal phoenicopterid.

Conclusions/Significance

Although the Podicipediformes-Phoenicopteriformes sister group relationship is now well supported, flamingos and grebes exhibit feeding, reproductive, and nesting strategies that diverge significantly. Our multi-disciplinary study is the first to reveal that the phoenicopteriform reproductive behaviour, nesting ecology and nest characteristics derived from grebe-like type strategies to reach the extremely specialized conditions observed in modern flamingo crown groups. Furthermore, our study enables us to map ecological and reproductive characters on the Phoenicopteriformes evolutionary lineage. Our results demonstrate that the nesting paleoenvironments of flamingos were closely linked to the unique ecology of this locality, which is a direct result of special climatic (high evaporitic regime) and geological (fault system) conditions.     

High Expression of Lewis y Antigen and CD44 Is Correlated with Resistance to Chemotherapy in Epithelial Ovarian Cancers

Objectives

To measure Lewis y antigen and CD44 antigen expression in epithelial ovarian carcinoma and to correlate the levels of these antigens with clinical response to chemotherapy.

Methods

The study cases included 34 cases of ovarian carcinoma with resistance to chemotherapeutic drugs, 6 partially drug-sensitive cases, and 52 drug-sensitive cases (92 total).

Results

The rates of expression of Lewis y antigen and CD44 antigen were significantly greater in the drug-resistant group than that in the partially-sensitive or sensitive groups. Surgical stage, residual tumor size and expression of CD44 and Lewis y antigen in ovarian carcinoma tissues were independent risk factors for chemotherapeutic drug resistance.

Conclusions

Over-expression of Lewis y and CD44 antigen are strong risk factors for chemotherapeutic drug resistance in ovarian carcinoma patients.     

Infectivity of Dengue Virus Serotypes 1 and 2 Is Correlated with E-Protein Intrinsic Dynamics but Not to Envelope Conformations

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Expression of a Soybean Hydroxyproline-Rich Glycoprotein Gene Is Correlated with Maturation of Roots

A novel extensin gene has been identified in soybean (Glycine max L.) that encodes a hydroxyproline-rich glycoprotein (SbHRGP3) with two different domains. In this study expression of SbHRGP3 was investigated during soybean root development. SbHRGP was expressed in roots of mature plants, as well as seedlings, and showed a distinct pattern of expression during root development. The expression of SbHRGP3 increased gradually during root development of seedlings and reached a maximum while the secondary roots were maturing. The maximum expression level was contributed mainly by the secondary roots rather than by the primary root. Furthermore, expression of SbHRGP3 was preferentially detected in the regions undergoing maturation of the primary and secondary roots. These results imply that the expression of SbHRGP3 is regulated in an organ- and development-specific manner and that in soybean SbHRGP3 expression may be required for root maturation, presumably for the cessation of root elongation. Wounding and sucrose in combination enhanced expression of SbHRGP3 in roots, whereas both wounding and sucrose were required for the expression of SbHRGP3 in leaves.     

Inhibition and Acclimation of Photosynthesis to Heat Stress Is Closely Correlated with Activation of Ribulose-1,5-Bisphosphate Carboxylase/Oxygenase

Increasing the leaf temperature of intact cotton (Gossypium hirsutum L.) and wheat (Triticum aestivum L.) plants caused a progressive decline in the light-saturated CO₂-exchange rate (CER). CER was more sensitive to increased leaf temperature in wheat than in cotton, and both species demonstrated photosynthetic acclimation when leaf temperature was increased gradually. Inhibition of CER was not a consequence of stomatal closure, as indicated by a positive relationship between leaf temperature and transpiration. The activation state of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), which is regulated by Rubisco activase, was closely correlated with temperature-induced changes in CER. Nonphotochemical chlorophyll fluorescence quenching increased with leaf temperature in a manner consistent with inhibited CER and Rubisco activation. Both nonphotochemical fluorescence quenching and Rubisco activation were more sensitive to heat stress than the maximum quantum yield of photochemistry of photosystem II. Heat stress led to decreased 3-phosphoglyceric acid content and increased ribulose-1,5-bisphosphate content, which is indicative of inhibited metabolite flow through Rubisco. We conclude that heat stress inhibited CER primarily by decreasing the activation state of Rubisco via inhibition of Rubisco activase. Although Rubisco activation was more closely correlated with CER than the maximum quantum yield of photochemistry of photosystem II, both processes could be acclimated to heat stress by gradually increasing the leaf temperature.     

A Dark Incubation Period Is Important for Agrobacterium-Mediated Transformation of Mature Internode Explants of Sweet Orange,Grapefruit, Citron,and a Citrange Rootstock

Background

Citrus has an extended juvenile phase and trees can take 2–20 years to transition to the adult reproductive phase and produce fruit. For citrus variety development this substantially prolongs the time before adult traits, such as fruit yield and quality, can be evaluated. Methods to transform tissue from mature citrus trees would shorten the evaluation period via the direct production of adult phase transgenic citrus trees.

Methodology/Principal Findings

Factors important for promoting shoot regeneration from internode explants from adult phase citrus trees were identified and included a dark incubation period and the use of the cytokinin zeatin riboside. Transgenic trees were produced from four citrus types including sweet orange, citron, grapefruit, and a trifoliate hybrid using the identified factors and factor settings.

Significance

The critical importance of a dark incubation period for shoot regeneration was established. These results confirm previous reports on the feasibility of transforming mature tissue from sweet orange and are the first to document the transformation of mature tissue from grapefruit, citron, and a trifoliate hybrid.