Mitochondrial‐targeted catalase is good for the old mouse proteome,but not for the young: ‘reverse’ antagonistic pleiotropy?

Reactive oxygen species (ROS) are highly reactive oxygen‐containing molecules associated with aging and a broad spectrum of pathologies. We have previously shown that transgenic expression of the antioxidant enzyme catalase targeted to the mitochondria (mCAT) in mice reduces ROS, attenuates age‐related disease, and increases lifespan. However, it has been increasingly recognized that ROS also has beneficial roles in signaling, hormesis, stress response, and immunity. We therefore hypothesized that mCAT might be beneficial only when ROS approaches pathological levels in older age and might not be advantageous at a younger age when basal ROS is low. We analyzed abundance and turnover of the global proteome in hearts and livers of young (4 month) and old (20 month) mCAT and wild‐type (WT) mice. In old hearts and livers of WT mice, protein half‐lives were reduced compared to young, while in mCAT mice the reverse was observed; the longest half‐lives were seen in old mCAT mice and the shortest in young mCAT. Protein abundance of old mCAT hearts recapitulated a more youthful proteomic expression profile (P‐value < 0.01). However, young mCAT mice partially phenocopied the older wild‐type proteome (P‐value < 0.01). Age strongly interacts with mCAT, consistent with antagonistic pleiotropy in the reverse of the typical direction. These findings underscore the contrasting roles of ROS in young vs. old mice and indicate the need for better understanding of the interaction between dose and age in assessing the efficacy of therapeutic interventions in aging, including mitochondrial antioxidants.     

Temperature-activity relationship for the intestinal Na<Superscript>+</Superscript>-K<Superscript>+</Superscript>-ATPase of<Emphasis Type="Italic"> Sparus aurata</Emphasis>. A role for the phospholipid microenvironment?

The temperature dependence for Na(+)-K(+)-ATPase has been examined in the proximal-distal axis of the intestine of gilthead seabream (Sparus aurata), i.e. pyloric caeca (PC), anterior intestine (AI) and posterior intestine (PI). Data derived from the Arrhenius plots showed differences in terms of temperature discontinuity points ( Td) (13.29 degrees C, 16.39 degrees C and 17.48 degrees C for PC, AI and PI, respectively) and activation energy ratios (Ea(2)/Ea(1)) obtained at both sides of Td (2.38, 1.98 and 1.78, for PC, AI and PI, respectively). The analyses of polar lipids showed differences in the levels of certain fatty acids among intestinal regions. The content of each fatty acid and different fatty acid ratios were correlated with the corresponding Td and Ea(2)/Ea(1) values. Regression analyses revealed the existence of strong negative correlations between docosahexaenoic acid (22:6n-3, DHA) or the DHA/monoenes ratio and Td. No obvious relationships were observed for other polyunsaturated fatty acids (PUFA) nor saturated fatty acids. The results obtained in the present study indicate that the heterogeneous values of Td displayed by the Na(+)-K(+)-ATPase along the intestinal tract could be related to a modulatory role of certain fatty acid within the lipid microenvironment of the enzyme.     

What about cultural ecosystems? Opportunities for cultural considerations in the “International Standards for the Practice of Ecological Restoration”

The Society for Ecological Restoration's 2016 (SER) “International Standards for the Practice of Ecological Restoration” is a living document intended to guide restoration projects “anywhere in the world.” Given its intended global scope and in hopes of informing future editions, this document is critically assessed in light of the role people have played in ecosystems around the world. We argue that the Standards has an underlying nature–culture dichotomization that limits its applicability; in qualifying what it calls “cultural ecosystems” for rehabilitation, rather than restoration, the Standards privileges colonial visions of ecological restoration. We also discuss the Standards' representation of the ecological impacts and practices of indigenous groups. Whereas the Standards claims that preindustrial cultural ecosystems exist in states similar to unmodified areas, many historians, anthropologists, and paleoecologists would point out that preindustrial people sometimes had massive environmental impacts through agriculture, hydrological engineering, over‐hunting, living in dense urban environments, transporting species, burning on a scale capable of changing the climate, and other practices. Furthermore, the Standards does not discuss how the cultural goals of indigenous groups fit into the overall picture of ecological restoration. Future drafts of the Standards should more accurately frame the diverse roles people play in nature, and create global standards that account for the validity of cultural goals for ecological restoration.     

Towards metagenome-scale models for industrial applications — the case of Lactic Acid Bacteria

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Highlights► Genome-scale metabolic modelling is being increasingly applied in LAB research. ► Novel techniques that broaden applicability of models remain to be applied to LAB. ► Additional constraints allow better predictions of genome-scale metabolic models. ► Novel approaches to move from modelling monocultures to mixed cultures are being developed. ► The feasibility of metagenome-based modelling approaches is being appreciated.     

A biomarker for the identification of four <Emphasis Type="Italic">Phaeoacremonium</Emphasis> species using the β-tubulin gene as the target sequence

A real-time polymerase chain reaction (PCR) was developed for the rapid detection and identification of Phaeoacremonium species, the fungi associated with severe diseases in grapevines. A degenerate primer pair (F2bt–R1bt) with homology to the β-tubulin gene was designed to be used in the amplification of 11 species of Phaeoacremonium. Four species-specific probes labelled with three different fluorescent dyes were designed to be used with the degenerate primers in a real-time PCR for the identification of Phaeoacremonium aleophilum, P. parasiticum, P. viticola and P. mortoniae. Combinations of two probes in a duplex real-time PCR allowed to detect and identify a mixture of Phaeoacremonium species and cross-amplifications were not detected. This method was applied to detect Phaeoacremonium species in eight wood fragments from grapevine plants naturally infected, and results were compared with those obtained with nested PCR and culturing on growth media. Real-time PCR detected Phaeoacremonium in 100% of the analysed fragments, whereas nested PCR did only in the 62% of them and requiring subsequent restriction fragment-length polymorphism analysis to identify the species. This method is a sensitive tool to detect and identify Phaeoacremonium species in infected grapevine wood. Real-time PCR assay defined here can be used in a plant nursery program to identify pathogen-free plants in order to manage Petri disease of grapevines.     

Can Management Improve the Value of Shade Plantations for the Endemic Species of São Tomé Island?

Cocoa and coffee are among the most valuable tropical crops, with much of their production in areas of high biodiversity. Although this could suggest a conflict between agricultural expansion and biodiversity conservation, these crops are normally grown in shade plantations—a more biodiversity‐friendly agroforestry system. Using São Tomé Island as a case study, we examined if shade plantation can benefit biodiversity by protecting extinction‐prone island endemic species. We found that shade plantations held rich assemblages, even in comparison with forest: we estimated 30 bird and 74 tree species occurring in plantations compared to 24 bird and 108 tree species in forests. However, the structure of the assemblages was significantly different between ecosystems, with an average dissimilarity of 33.8 percent and 87.9 percent for birds and trees, respectively. Shade plantations had consistently less endemic species than the forest; we estimated a drop from 17 to 13 in birds and from 17 to 3 in trees. We also found that despite marked differences in the response of bird species to the vegetation characteristics of shade plantations, there was a strong positive link between aboveground tree biomass and endemic species richness and abundance. These results show that shade plantations hold assemblages impoverished in endemic species, but that management can improve their value for the conservation of these species. Finally, we suggest that biodiversity‐friendly certification and carbon markets are used to implement and guarantee the long‐term economical sustainability of practices that favor the endemic species in São Tomé's shade plantations.     

The evidence‐based group‐level symptom‐reduction model as the organizing principle for mental health care: time for change?

The content and organization of mental health care have been heavily influenced by the view that mental difficulties come as diagnosable disorders that can be treated by specialist practitioners who apply evidence‐based practice (EBP) guidelines of symptom reduction at the group level. However, the EBP symptom‐reduction model is under pressure, as it may be disconnected from what patients need, ignores evidence of the trans‐syndromal nature of mental difficulties, overestimates the contribution of the technical aspects of treatment compared to the relational and ritual components of care, and underestimates the lack of EBP group‐to‐individual generalizability. A growing body of knowledge indicates that mental illnesses are seldom “cured” and are better framed as vulnerabilities. Important gains in well‐being can be achieved when individuals learn to live with mental vulnerabilities through a slow process of strengthening resilience in the social and existential domains. In this paper, we examine what a mental health service would look like if the above factors were taken into account. The mental health service of the 21st century may be best conceived of as a small‐scale healing community fostering connectedness and strengthening resilience in learning to live with mental vulnerability, complemented by a limited number of regional facilities. Peer support, organized at the level of a recovery college, may form the backbone of the community. Treatments should be aimed at trans‐syndromal symptom reduction, tailored to serve the higher‐order process of existential recovery and social participation, and applied by professionals who have been trained to collaborate, embrace idiography and maximize effects mediated by therapeutic relationship and the healing effects of ritualized care interactions. Finally, integration with a public mental health system of e‐communities providing information, peer and citizen support and a range of user‐rated self‐management tools may help bridge the gap between the high prevalence of common mental disorder and the relatively low capacity of any mental health service.     

Is the weighted z‐test the best method for combining probabilities from independent tests?

Through simulation, Whitlock showed that when all the alternatives have the same effect size, the weighted z-test is superior to both unweighted z-test and Fisher's method when combining P-values from independent studies. In this paper, we show that under the same situation, the generalized Fisher method due to Lancaster outperforms the weighted z-test.     

Translational biomaterials — the journey from the bench to the market — think ‘product’

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值得关切的严重急性呼吸综合征冠状病毒2型变异株

自2019年12月2019冠状病毒病暴发流行以来,严重急性呼吸综合征冠状病毒 2 型已经产生了1万个以上的变异株。其中有些可能获得更强的传染性,有的致病性得以提高,有的或许不能被现有的检测试剂检测出来,还有的也许能够逃逸疫苗的免疫保护作用。世界卫生组织于2021年5月31日发布了针对这些变异株的新的命名系统。本文对当前世界上流行较广的4个变异株进行综述,包括最近在广州市引起小暴发的δ变异株。     

Development of successive cambia and formation of flat stems in Rhynchosia pyramidalis (Lam.) Urb. (Fabaceae)

Stem flattening in Rhynchosia pyramidalis (Fabaceae) is achieved by the development of crescent-shaped successive cambia on two opposite sides of the stem (referred hereafter as distal side). Other lateral sides of the stem (adjacent to supporting host and its opposite side, referred as proximal sides) usually possess single cambium. In the young stems, parenchymatous cells located outside to protophloem of distal side dedifferentiate and develop small segments of cambium. Concomitant to bidirectional differentiation of the secondary xylem and phloem, these newly developed cambial segments also extend in tangential directions. Differential activity of newly developed crescent-shaped cambial segments deposits more secondary xylem at median position as compared to their terminal ends of the stem on distal side; consequently, it pushes the cambial segment outside, thus resulting in crescent-shaped arcs of the cambia only on two opposite sides. After the production of 1–2 mm of secondary xylem, they cease to divide and new segments of cambial arc develop on the same side in a similar fashion. Such repeated behaviour of successive cambia development consequently leads to the formation of tangentially flat stems. The secondary xylem is diffusely porous with indistinct growth rings and is composed of vessels (wide and narrow), fibres, axial ray parenchyma cells, while phloem consisted of sieve elements, companion cells, axial and ray parenchyma. Rays in both xylem and phloem are uni- to multiseriate and heterocellular. The structure of secondary xylem and development of successive cambia is correlated with climbing habit.     

Genetic and immunological analysis of a novel variant of Shiga toxin 1 from bovine Escherichia coli strains and development of bead-ELISA to detect the variant toxin

A novel variant of Shiga toxin 1 (Stx1) was identified from bovine Escherichia coli strains. The stx1 variant genes designated as stx1v51 and stx1v52 were cloned and sequenced. The two variant genes differed each other by 2 bp, but the deduced amino acid sequences of the two Stx1 variant toxins were the same and had 94% and 92% homology to that of prototype A and B subunits of Stx1, respectively. The variant toxin designated as Stx1v52 was purified to homogeneity. Although inhibition of protein synthesis in vitro by purified Stx1v52 was almost equal to that of purified Stx1, Vero cell cytotoxicity and mouse lethality of Stx1v52 were several folds lower than those of prototype Stx1. In Ouchterlony double gel diffusion test, the precipitin line between Stx1v52 and Stx1 formed a spur against anti-Stx1 serum but was fused against anti-Stx1v52 serum. Stx1v52 and Stx1v52-specific-bead-ELISA was developed, and both Stx1 and Stx1v52 could be detected with high sensitivity using Stx1v52 conjugate. However, Stx1v52 but not Stx1 could be detected with Stx1v52-specific bead-ELISA.     

Novel Mutations in the CLCN1 Gene of Myotonia Congenita: 2 Case Reports

Introduction: Myotonia Congenita is an inherited myotonia that is due to a mutation in the skeletal muscle chloride channel CLCN1. These mutations lead to reduced sarcolemmal chloride conductance, causing delayed muscle relaxation that is evident as clinical and electrical myotonia.Methods: We report the clinical presentations of two individuals with Myotonia Congenita (MC).Results: Patient 1 has been diagnosed with the recessive form of MC, known as the Becker variant, and Patient 2 has been diagnosed with the dominant form of MC, known as the Thomsen variant. In both patients, the diagnosis was made based on the clinical presentation, EMG and CLCN1 gene sequencing. Patient 1 also had a muscle biopsy.Conclusions: Genetic testing in both patients reveals previously unidentified mutations in the CLCN1 gene specific to Myotonia Congenita. We report the salient clinical features of each patient and discuss the effects and common types of CLCN1 mutations and review the literature.     

Molecular cloning and characterization of mouse aquaporin 6

In the rat kidney, aquaporin (AQP) 6 is localized in the intracellular vesicle membranes of type-A intercalated cells of the collecting duct; mouse AQP6 (mAQP6) has not been characterized. Although mAQP6 was originally cloned from cDNA in a mouse cerebellum library (GenBank NM 175087), we have independently cloned a cDNA encoding mAQP6 from an adult kidney cDNA library (C57BL/6J strain). We identified two different spliced variants of mAQP6: mAQP6a and mAQP6b. The mAQP6a isoform is almost identical to that of rat AQP6, whereas mAQP6b is identical to that reported in the mouse cerebellum library mentioned above. We found that the mRNA expression of these two spliced variants is regulated in a tissue-specific and age-dependent manner. Functional analyses of water and ion permeation revealed that mAQP6a functions like rat AQP6 and that mAQP6b does not function as either a water channel or an ion channel under our experimental conditions.     

REVA as A Well-curated Database for Human Expression-modulating Variants

More than 90% of disease- and trait-associated human variants are noncoding. By systematically screening multiple large-scale studies, we compiled REVA, a manually curated database for over 11.8 million experimentally tested noncoding variants with expression-modulating potentials. We provided 2424 functional annotations that could be used to pinpoint the plausible regulatory mechanism of these variants. We further benchmarked multiple state-of-the-art computational tools and found that their limited sensitivity remains a serious challenge for effective large-scale analysis. REVA provides high-quality experimentally tested expression-modulating variants with extensive functional annotations, which will be useful for users in the noncoding variant community. REVA is freely available at http://reva.gao-lab.org.     

初论蜘蛛目的种内变异类型

研究蜘蛛目中的种内变异，初步探讨蜘蛛的外生殖器结构的变异类型，并提出在蜘蛛分类学中树立种群分类概念的重要性。