Lactobacillus
and
Bifidobacterium
spp. are best understood for their applications as probiotics, which are often transient, but as commensals it is probable that stable colonization in the gut is ...important for their beneficial roles. Recent research suggests that the establishment and persistence of strains of
Lactobacillus
and
Bifidobacterium
in the gut are species- and strain-specific and affected by natural history, genomic adaptability, and metabolic interactions of the bacteria and the microbiome and immune aspects of the host but also regulated by diet. This provides new perspectives on the underlying molecular mechanisms. With an emphasis on host-microbe interaction, this review outlines how the characteristics of individual
Lactobacillus
and
Bifidobacterium
bacteria, the host genotype and microbiome structure,diet, and host-microbe coadaptation during bacterial gut transition determine and influence the colonization process. The diet-tuned and personally tailored colonization can be achieved via a machine learning prediction model proposed here.
Xenacoelomorpha is the sister group to Nephrozoa Cannon, Johanna Taylor; Vellutini, Bruno Cossermelli; Smith, 3rd, Julian ...
Nature (London),
02/2016, Letnik:
530, Številka:
7588
Journal Article
Recenzirano
Odprti dostop
The position of Xenacoelomorpha in the tree of life remains a major unresolved question in the study of deep animal relationships. Xenacoelomorpha, comprising Acoela, Nemertodermatida, and ...Xenoturbella, are bilaterally symmetrical marine worms that lack several features common to most other bilaterians, for example an anus, nephridia, and a circulatory system. Two conflicting hypotheses are under debate: Xenacoelomorpha is the sister group to all remaining Bilateria (= Nephrozoa, namely protostomes and deuterostomes) or is a clade inside Deuterostomia. Thus, determining the phylogenetic position of this clade is pivotal for understanding the early evolution of bilaterian features, or as a case of drastic secondary loss of complexity. Here we show robust phylogenomic support for Xenacoelomorpha as the sister taxon of Nephrozoa. Our phylogenetic analyses, based on 11 novel xenacoelomorph transcriptomes and using different models of evolution under maximum likelihood and Bayesian inference analyses, strongly corroborate this result. Rigorous testing of 25 experimental data sets designed to exclude data partitions and taxa potentially prone to reconstruction biases indicates that long-branch attraction, saturation, and missing data do not influence these results. The sister group relationship between Nephrozoa and Xenacoelomorpha supported by our phylogenomic analyses implies that the last common ancestor of bilaterians was probably a benthic, ciliated acoelomate worm with a single opening into an epithelial gut, and that excretory organs, coelomic cavities, and nerve cords evolved after xenacoelomorphs separated from the stem lineage of Nephrozoa.
Cold-adapted microorganisms inhabiting permanently low-temperature environments were initially just a biological curiosity but have emerged as rich sources of numerous valuable tools for application ...in a broad spectrum of innovative technologies. To overcome the multiple challenges inherent to life in their cold habitats, these microorganisms have developed a diverse array of highly sophisticated synergistic adaptations at all levels within their cells: from cell envelope and enzyme adaptation, to cryoprotectant and chaperone production, and novel metabolic capabilities. Basic research has provided valuable insights into how these microorganisms can thrive in their challenging habitat conditions and into the mechanisms of action of the various adaptive features employed, and such insights have served as a foundation for the knowledge-based development of numerous novel biotechnological tools. In this review, we describe the current knowledge of the adaptation strategies of cold-adapted microorganisms and the biotechnological perspectives and commercial tools emerging from this knowledge. Adaptive features and, where possible, applications, in relation to membrane fatty acids, membrane pigments, the cell wall peptidoglycan layer, the lipopolysaccharide component of the outer cell membrane, compatible solutes, antifreeze and ice-nucleating proteins, extracellular polymeric substances, biosurfactants, chaperones, storage materials such as polyhydroxyalkanoates and cyanophycins and metabolic adjustments are presented and discussed.
Climate warming will influence photosynthesis via thermal effects and by altering soil moisture
. Both effects may be important for the vast areas of global forests that fluctuate between periods ...when cool temperatures limit photosynthesis and periods when soil moisture may be limiting to carbon gain
. Here we show that the effects of climate warming flip from positive to negative as southern boreal forests transition from rainy to modestly dry periods during the growing season. In a three-year open-air warming experiment with juveniles of 11 temperate and boreal tree species, an increase of 3.4 °C in temperature increased light-saturated net photosynthesis and leaf diffusive conductance on average on the one-third of days with the wettest soils. In all 11 species, leaf diffusive conductance and, as a result, light-saturated net photosynthesis decreased during dry spells, and did so more sharply in warmed plants than in plants at ambient temperatures. Consequently, across the 11 species, warming reduced light-saturated net photosynthesis on the two-thirds of days with driest soils. Thus, low soil moisture may reduce, or even reverse, the potential benefits of climate warming on photosynthesis in mesic, seasonally cold environments, both during drought and in regularly occurring, modestly dry periods during the growing season.
Category:
Midfoot/Forefoot
Introduction/Purpose:
Outcomes following surgical reconstruction for acquired flatfoot deformity secondary to posterior tibial tendon dysfunction have been well described. ...However, the majority of studies have a limited number of patients or short to mid- term follow-up. The purpose of this study was to report the natural history, demographics, and mechanisms of treatment failure for patients undergoing flatfoot reconstruction at a single institution by a single surgeon.
Methods:
With IRB approval, 321 consecutive patients undergoing flatfoot reconstruction during a 14-year period were included in this study (February 2002 through October 2016). All procedures were performed by a single surgeon (PJJ) at our institution. Demographic data, surgical data, clinic notes, and radiographs were available for review. Exclusion criteria included patients without electronic records or incomplete data. Failure was defined as a need to return to the operating room for revision surgery. Statistical analysis was performed.
Results:
321 consecutive patients underwent flatfoot reconstruction from 2002-2016. The majority of patients were female (83.2%) with left laterality (58.6%) & a body mass index classified as overweight (21.5%) or obese (56.4%). 13.7% of patients were diabetics, and 18.4% were current smokers. 54 patients (16.8%) experienced treatment failure. Painful calcaneal hardware requiring removal occurred in 11.8% of patients, conversion to triple arthrodesis occurred in 3.45%, and wound complications or infection requiring irrigation & debridement occurred in 1.87%. There were no mortalities reported within 90 days. There were 3 symptomatic deep vein thromboses, none requiring surgical intervention, & no pulmonary embolisms. A significant increase in relative risk of treatment failure was calculated for female gender, current cigarette use, & age under 60 (3.4 p=0.0005/1.9 p=0.0081/1.8 p=0.042).
Conclusion:
This study represents the largest series of patients undergoing flatfoot reconstruction by a single surgeon at a single institution. Although retrospective, the results provide valuable insight to the natural history of patients undergoing this procedure. The overall complication rate and treatment failure rates are low and similar to those previously reported in the literature. Patients with female gender or under 60 years of age should be notified of their increased relative risk of treatment failure & counseled accordingly. Smoking cessation is recommended to reduce the risk of treatment failure.
Lymexylidae is a small beetle family, with some members exhibiting strongly reduced elytra and largely exposed functional hind wings. Previously, four species from Kachin (Myanmar), Baltic, and Rovno ...ambers were assigned to the extant lymexylid genus Raractocetus. Our new examination suggests that these fossils are morphologically separated from the extant Raractocetus, primarily in the hind wing venation, and should be removed from Raractocetus. The fossils once assigned to Raractocetus Kurosawa from the Mesozoic and Cenozoic amber deposits differ from extant Raractocetus in the longer elytra, the more strongly projecting metacoxae, and the hind wing with vein 2A forked. Thus, these fossils should be removed from Raractocetus. Cretoquadratus engeli Chen from Kachin amber appears to be conspecific with R.fossilis Yamamoto. As a result, R. fossilis and R. extinctus Yamamoto from Kachin amber, R. balticus Yamamoto from Baltic amber, and R. sverlilo Nazarenko, Perkovsky & Yamamoto from Rovno amber are transferred to Cretoquadratus Chen, as C.fossilis (Yamamoto) comb. nov., C. extinctus (Yamamoto) comb. nov., C. balticus (Yamamoto) comb. nov., and C. sverlilo (Nazarenko, Perkovsky & Yamamoto) comb. nov., and C. engelisyn. nov. is suggested to be a junior synonym of C. fossilis.
Background
There are sparse and conflicting data regarding the long‐term clinical course of atopic dermatitis (AD). Although often described as a childhood disease, newer population‐based estimates ...suggest the prevalence of pediatric and adult disease may be similar.
Methods
Our objective was to determine whether there is a decline in the prevalence of AD in population‐based cohorts of patients followed longitudinally beyond childhood. We conducted a systematic review and meta‐analysis including studies assessing AD prevalence across 3 or more points in time. The primary outcome was weighted overall risk difference (percentage decrease in AD prevalence).
Results
Of 2080 references reviewed, 7 studies with 13 515 participants were included. Participants were assessed at 3‐6 time points, ranging from age 3 months to 26 years. The percentage decrease in prevalence after age 12 was 1%, which was not significantly different from zero (95% confidence interval −2%‐5%). Similar results were found with other age cut‐offs.
Conclusion
The prevalence of AD in longitudinal birth cohort studies is similar in childhood and adolescence/early adulthood.
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