Bdelloid rotifers are a class of microscopic invertebrates that have existed for millions of years apparently without sex or meiosis. They inhabit a variety of temporary and permanent freshwater ...habitats globally, and many species are remarkably tolerant of desiccation. Bdelloids offer an opportunity to better understand the evolution of sex and recombination, but previous work has emphasised desiccation as the cause of several unusual genomic features in this group. Here, we present high-quality whole-genome sequences of 3 bdelloid species: Rotaria macrura and R. magnacalcarata, which are both desiccation intolerant, and Adineta ricciae, which is desiccation tolerant. In combination with the published assembly of A. vaga, which is also desiccation tolerant, we apply a comparative genomics approach to evaluate the potential effects of desiccation tolerance and asexuality on genome evolution in bdelloids. We find that ancestral tetraploidy is conserved among all 4 bdelloid species, but homologous divergence in obligately aquatic Rotaria genomes is unexpectedly low. This finding is contrary to current models regarding the role of desiccation in shaping bdelloid genomes. In addition, we find that homologous regions in A. ricciae are largely collinear and do not form palindromic repeats as observed in the published A. vaga assembly. Consequently, several features interpreted as genomic evidence for long-term ameiotic evolution are not general to all bdelloid species, even within the same genus. Finally, we substantiate previous findings of high levels of horizontally transferred nonmetazoan genes in both desiccating and nondesiccating bdelloid species and show that this unusual feature is not shared by other animal phyla, even those with desiccation-tolerant representatives. These comparisons call into question the proposed role of desiccation in mediating horizontal genetic transfer.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
There is growing interest in using PET/CT for evaluating early response to therapy in cancer treatment. Although widely available and convenient to use, standardized uptake value (SUV) measurements ...can be influenced by a variety of biologic and technologic factors. Many of these factors can be addressed with close attention to detail and appropriate quality control. This article will review factors potentially affecting SUV measurements and provide recommendations on ways to minimize when using serial PET to assess early response to therapy.
Scanner and reconstruction parameters can significantly affect SUV measurements. When using serial SUV measurements to assess early response to therapy, imaging should be performed on the same scanner using the same image acquisition and reconstruction protocols. In addition, attention to detail is required for accurate determination of the administered radiopharmaceutical dose.
Abstract Context Robot-assisted radical prostatectomy (RARP) was proposed to improve functional outcomes in comparison with retropubic radical prostatectomy (RRP) or laparoscopic radical ...prostatectomy (LRP). In the initial RARP series, 12-mo urinary continence recovery rates ranged from 84% to 97%. However, the few available studies comparing RARP with RRP or LRP published before 2008 did not permit any definitive conclusions about the superiority of any one of these techniques in terms of urinary continence recovery. Objective The aims of this systematic review were (1) to evaluate the prevalence and risk factors for urinary incontinence after RARP, (2) to identify surgical techniques able to improve urinary continence recovery after RARP, and (3) to perform a cumulative analysis of all available studies comparing RARP versus RRP or LRP in terms of the urinary continence recovery rate. Evidence acquisition A literature search was performed in August 2011 using the Medline, Embase, and Web of Science databases. The Medline search included only a free-text protocol using the term radical prostatectomy across the title and abstract fields of the records. The following limits were used: humans; gender (male); and publication date from January 1, 2008. Searches of the Embase and Web of Science databases used the same free-text protocol, keywords, and search period. Only comparative studies or clinical series including >100 cases reporting urinary continence outcomes were included in this review. Cumulative analysis was conducted using the Review Manager v.4.2 software designed for composing Cochrane Reviews (Cochrane Collaboration, Oxford, UK). Evidence synthesis We analyzed 51 articles reporting urinary continence rates after RARP: 17 case series, 17 studies comparing different techniques in the context of RARP, 9 studies comparing RARP with RRP, and 8 studies comparing RARP with LRP. The 12-mo urinary incontinence rates ranged from 4% to 31%, with a mean value of 16% using a no pad definition. Considering a no pad or safety pad definition, the incidence ranged from 8% to 11%, with a mean value of 9%. Age, body mass index, comorbidity index, lower urinary tract symptoms, and prostate volume were the most relevant preoperative predictors of urinary incontinence after RARP. Only a few comparative studies evaluated the impact of different surgical techniques on urinary continence recovery after RARP. Posterior musculofascial reconstruction with or without anterior reconstruction was associated with a small advantage in urinary continence recovery 1 mo after RARP. Only complete reconstruction was associated with a significant advantage in urinary continence 3 mo after RARP (odds ratio OR: 0.76; p = 0.04). Cumulative analyses showed a better 12-mo urinary continence recovery after RARP in comparison with RRP (OR: 1.53; p = 0.03) or LRP (OR: 2.39; p = 0.006). Conclusions The prevalence of urinary incontinence after RARP is influenced by preoperative patient characteristics, surgeon experience, surgical technique, and methods used to collect and report data. Posterior musculofascial reconstruction seems to offer a slight advantage in terms of 1-mo urinary continence recovery. Update of a previous systematic review of literature shows, for the first time, a statistically significant advantage in favor of RARP in comparison with both RRP and LRP in terms of 12-mo urinary continence recovery.
Abstract Background Although the initial robot-assisted radical prostatectomy (RARP) series showed 12-mo potency rates ranging from 70% to 80%, the few available comparative studies did not permit ...any definitive conclusion about the superiority of this technique when compared with retropubic radical prostatectomy (RRP) and laparoscopic radical prostatectomy (LRP). Objectives The aims of this systematic review were (1) to evaluate the current prevalence and the potential risk factors of erectile dysfunction after RARP, (2) to identify surgical techniques able to improve the rate of potency recovery after RARP, and (3) to perform a cumulative analysis of all available studies comparing RARP versus RRP or LRP. Evidence acquisition A literature search was performed in August 2011 using the Medline, Embase, and Web of Science databases. Only comparative studies or clinical series including >100 cases reporting potency recovery outcomes were included in this review. Cumulative analysis was conducted using Review Manager v.4.2 software designed for composing Cochrane Reviews (Cochrane Collaboration, Oxford, UK). Evidence synthesis We analyzed 15 case series, 6 studies comparing different techniques in the context of RARP, 6 studies comparing RARP with RRP, and 4 studies comparing RARP with LRP. The 12- and 24-mo potency rates ranged from 54% to 90% and from 63% to 94%, respectively. Age, baseline potency status, comorbidities index, and extension of the nerve-sparing procedure represent the most relevant preoperative and intraoperative predictors of potency recovery after RARP. Available data seem to support the use of cautery-free dissection or the use of pinpointed low-energy cauterization. Cumulative analyses showed better 12-mo potency rates after RARP in comparison with RRP (odds ratio OR: 2.84; 95% confidence interval CI: 1.46–5.43; p = 0.002). Only a nonstatistically significant trend in favor of RARP was reported after comparison with LRP (OR: 1.89; p = 0.21). Conclusions The incidence of potency recovery after RARP is influenced by numerous factors. Data coming from the present systematic review support the use of a cautery-free technique. This update of previous systematic reviews of the literature showed, for the first time, a significant advantage in favor of RARP in comparison with RRP in terms of 12-mo potency rates.
A few metazoan lineages are thought to have persisted for millions of years without sexual reproduction. If so, they would offer important clues to the evolutionary paradox of sex itself 1, 2. Most ...“ancient asexuals” are subject to ongoing doubt because extant populations continue to invest in males 3–9. However, males are famously unknown in bdelloid rotifers, a class of microscopic invertebrates comprising hundreds of species 10–12. Bdelloid genomes have acquired an unusually high proportion of genes from non-metazoans via horizontal transfer 13–17. This well-substantiated finding has invited speculation 13 that homologous horizontal transfer between bdelloid individuals also may occur, perhaps even “replacing” sex 14. In 2016, Current Biology published an article claiming to supply evidence for this idea. Debortoli et al. 18 sampled rotifers from natural populations and sequenced one mitochondrial and four nuclear loci. Species assignments were incongruent among loci for several samples, which was interpreted as evidence of “interspecific horizontal genetic transfers.” Here, we use sequencing chromatograms supplied by the authors to demonstrate that samples treated as individuals actually contained two or more highly divergent mitochondrial and ribosomal sequences, revealing cross-contamination with DNA from multiple animals of different species. Other chromatograms indicate contamination with DNA from conspecific animals, explaining genetic and genomic evidence for “intraspecific horizontal exchanges” reported in the same study. Given the clear evidence of contamination, the data and findings of Debortoli et al. 18 provide no reliable support for their conclusions that DNA is transferred horizontally between or within bdelloid species.
•Clear evidence that findings in a 2016 article are artifacts of experimental error•A new method to analyze Sanger chromatograms reveals contamination between samples•No credible evidence for horizontal DNA exchange within or between bdelloid species•The evolutionary scandal of the asexual rotifers continues to defy resolution
Wilson et al. re-examine raw data from a 2016 article that had reported lateral transfer of DNA between bdelloid rotifers in lieu of sex. Samples that were supposed to contain DNA from a single animal are found to have included DNA from two or three different rotifers, revealing that data and conclusions from the earlier publication are unreliable.
Abstract Context Despite the large diffusion of robot-assisted radical prostatectomy (RARP), literature and data on the oncologic outcome of RARP are limited. Objective Evaluate lymph node yield, ...positive surgical margins (PSMs), use of adjuvant therapy, and biochemical recurrence (BCR)–free survival following RARP and perform a cumulative analysis of all studies comparing the oncologic outcomes of RARP and retropubic radical prostatectomy (RRP) or laparoscopic radical prostatectomy (LRP). Evidence acquisition A systematic review of the literature was performed in August 2011, searching Medline, Embase, and Web of Science databases. A free-text protocol using the term radical prostatectomy was applied. The following limits were used: humans; gender (male); and publications dating from January 1, 2008. A cumulative analysis was conducted using Review Manager software v.4.2 (Cochrane Collaboration, Oxford, UK) and Stata 11.0 SE software (StataCorp, College Station, TX, USA). Evidence synthesis We retrieved 79 papers evaluating oncologic outcomes following RARP. The mean PSM rate was 15% in all comers and 9% in pathologically localized cancers, with some tumor characteristics being the most relevant predictors of PSMs. Several surgeon-related characteristics or procedure-related issues may play a major role in PSM rates. With regard to BCR, the very few papers with a follow-up duration >5 yr demonstrated 7-yr BCR-free survival estimates of approximately 80%. Finally, all the cumulative analyses comparing RARP with RRP and comparing RARP with LRP demonstrated similar overall PSM rates (RARP vs RRP: odds ratio OR: 1.21; p = 0.19; RARP vs LRP: OR: 1.12; p = 0.47), pT2 PSM rates (RARP vs RRP: OR: 1.25; p = 0.31; RARP vs LRP: OR: 0.99; p = 0.97), and BCR-free survival estimates (RARP vs RRP: hazard ratio HR: 0.9; p = 0.526; RARP vs LRP: HR: 0.5; p = 0.141), regardless of the surgical approach. Conclusions PSM rates are similar following RARP, RRP, and LRP. The few data available on BCR from high-volume centers are promising, but definitive comparisons with RRP or LRP are not currently possible. Finally, significant data on cancer-specific mortality are not currently available.
Take Home Message The technology for robotic surgery continues to evolve. Robotic surgery has allowed us the opportunity to critically analyze outcomes and improve surgical technique both open and ...robotic. The new da Vinci Xi may allow us to do even more complex surgeries with minimally invasive techniques, but the true advantages remain to be seen.
Abstract Context Perioperative complications are a major surgical outcome for radical prostatectomy (RP). Objective Evaluate complication rates following robot-assisted RP (RARP), risk factors for ...complications after RARP, and surgical techniques to improve complication rates after RARP. We also performed a cumulative analysis of all studies comparing RARP with retropubic RP (RRP) or laparoscopic RP (LRP) in terms of perioperative complications. Evidence acquisition A systematic review of the literature was performed in August 2011, searching Medline, Embase, and Web of Science databases. A free-text protocol using the term radical prostatectomy was applied. The following limits were used: humans; gender (male); and publications dating from January 1, 2008. A cumulative analysis was conducted using Review Manager software v.4.2 (Cochrane Collaboration, Oxford, UK). Evidence synthesis We retrieved 110 papers evaluating oncologic outcomes following RARP. Overall mean operative time is 152 min; mean blood loss is 166 ml; mean transfusion rate is 2%; mean catheterization time is 6.3 d; and mean in-hospital stay is 1.9 d. The mean complication rate was 9%, with most of the complications being of low grade. Lymphocele/lymphorrea (3.1%), urine leak (1.8%), and reoperation (1.6%) are the most prevalent surgical complications. Blood loss (weighted mean difference: 582.77; p < 0.00001) and transfusion rate (odds ratio OR: 7.55; p < 0.00001) were lower in RARP than in RRP, whereas only transfusion rate (OR: 2.56; p = 0.005) was lower in RARP than in LRP. All the other analyzed parameters were similar, regardless of the surgical approach. Conclusions RARP can be performed routinely with a relatively small risk of complications. Surgical experience, clinical patient characteristics, and cancer characteristics may affect the risk of complications. Cumulative analyses demonstrated that blood loss and transfusion rates were significantly lower with RARP than with RRP, and transfusion rates were lower with RARP than with LRP, although all other features were similar regardless of the surgical approach.
Bdelloid rotifer genomes show signatures of asyngamous recombination leading to loss of heterozygosity. This has been hypothesised to occur via chromosome pairing during egg formation through a ...meiosis-like but non-reductional process.Evidence of genetic exchange in bdelloid populations requires further validation in our view.Around 10% of bdelloid genes have been acquired horizontally from other kingdoms of life; the mechanisms and consequences of high horizontal gene transfer (HGT) prevalence remain to be confirmed by functional and comparative studies.Bdelloids tolerate desiccation and radiation stress, and appear to repair the resulting DNA double-strand breaks by different mechanisms in the soma versus germline; other aspects of stress tolerance remain to be investigated.Links between parthenogenesis, desiccation tolerance and horizontal gene transfer have been hypothesised, but several key steps remain to be tested.
Bdelloid rotifers constitute a class of microscopic animals living in freshwater habitats worldwide. Several strange features of bdelloids have drawn attention: their ability to tolerate desiccation and other stresses, a lack of reported males across the clade despite centuries of study, and unusually high numbers of horizontally acquired, non-metazoan genes. Genome sequencing is transforming our understanding of their lifestyle and its consequences, while in turn providing wider insights about recombination and genome organisation in animals. Many questions remain, not least how to reconcile apparent genomic signatures of sex with the continued absence of reported males, why bdelloids have so many horizontally acquired genes, and how their remarkable ability to survive stress interacts with recombination and other genomic processes.
Bdelloid rotifers constitute a class of microscopic animals living in freshwater habitats worldwide. Several strange features of bdelloids have drawn attention: their ability to tolerate desiccation and other stresses, a lack of reported males across the clade despite centuries of study, and unusually high numbers of horizontally acquired, non-metazoan genes. Genome sequencing is transforming our understanding of their lifestyle and its consequences, while in turn providing wider insights about recombination and genome organisation in animals. Many questions remain, not least how to reconcile apparent genomic signatures of sex with the continued absence of reported males, why bdelloids have so many horizontally acquired genes, and how their remarkable ability to survive stress interacts with recombination and other genomic processes.
The fastest and most manoeuvrable terrestrial animals are found in savannah habitats, where predators chase and capture running prey. Hunt outcome and success rate are critical to survival, so both ...predator and prey should evolve to be faster and/or more manoeuvrable. Here we compare locomotor characteristics in two pursuit predator-prey pairs, lion-zebra and cheetah-impala, in their natural savannah habitat in Botswana. We show that although cheetahs and impalas were universally more athletic than lions and zebras in terms of speed, acceleration and turning, within each predator-prey pair, the predators had 20% higher muscle fibre power than prey, 37% greater acceleration and 72% greater deceleration capacity than their prey. We simulated hunt dynamics with these data and showed that hunts at lower speeds enable prey to use their maximum manoeuvring capacity and favour prey survival, and that the predator needs to be more athletic than its prey to sustain a viable success rate.
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