bluuebunny/crossref_metadata_2025 huggingface dataset:
Long COVID syndrome and the lung: how long will it last?
Authors: Mitchell P D , Olaniyi J , Buckley C , Donnelly S C
Published: March 2022

The prevalence and duration of the long-term respiratory complications of COVID-19 infection remains to be elucidated. This short commentary reports on recently published studies in patients post-acute COVID-19 infection in terms of symptom prevalence, physiological and radiological sequela and where only symptoms are present despite investigation. Pulmonary function testing, 6-min walk tests, computed tomography chest and more advanced imaging modalities have been incorporated to reveal the underlying pathophysiology that cause such disabling symptoms in patient with post-acute COVID-9 syndrome (PACS). PACS has a serious impact on people’s ability to return to work, affecting the physical, mental, social sphere and with significant healthcare and general economic consequences for them, their families and society.
The impact of a csDMARD in combination with a TNF inhibitor on drug retention and clinical remission in axial spondyloarthritis
Authors: Nissen Michael , Delcoigne Bénédicte , Di Giuseppe Daniela , Jacobsson Lennart , Hetland Merete Lund , Ciurea Adrian , Nekvindova Lucie , Iannone Florenzo , Akkoc Nurullah , Sokka-Isler Tuulikki , Fagerli Karen Minde , Santos Maria Jose , Codreanu Catalin , Pombo-Suarez Manuel , Rotar Ziga , Gudbjornsson Bjorn , van der Horst-Bruinsma Irene , Loft Anne Gitte , Möller Burkhard , Mann Herman , Conti Fabrizio , Yildirim Cetin Gozde , Relas Heikki , Michelsen Brigitte , Avila Ribeiro Pedro , Ionescu Ruxandra , Sanchez-Piedra Carlos , Tomsic Matija , Geirsson Árni Jón , Askling Johan , Glintborg Bente , Lindström Ulf
Published: March 2022

Objectives

Many axial spondylarthritis (axSpA) patients receive a conventional synthetic DMARD (csDMARD) in combination with a TNF inhibitor (TNFi). However, the value of this co-therapy remains unclear. The objectives were to describe the characteristics of axSpA patients initiating a first TNFi as monotherapy compared with co-therapy with csDMARD, to compare one-year TNFi retention and remission rates, and to explore the impact of peripheral arthritis.

Methods

Data was collected from 13 European registries. One-year outcomes included TNFi retention and hazard ratios (HR) for discontinuation with 95% CIs. Logistic regression was performed with adjusted odds ratios (OR) of achieving remission (Ankylosing Spondylitis Disease Activity Score (ASDAS)-CRP < 1.3 and/or BASDAI < 2) and stratified by treatment. Inter-registry heterogeneity was assessed using random-effect meta-analyses, combined results were presented when heterogeneity was not significant. Peripheral arthritis was defined as ≥1 swollen joint at baseline (=TNFi start).

Results

Amongst 24 171 axSpA patients, 32% received csDMARD co-therapy (range across countries: 13.5% to 71.2%). The co-therapy group had more baseline peripheral arthritis and higher CRP than the monotherapy group. One-year TNFi-retention rates (95% CI): 79% (78, 79%) for TNFi monotherapy vs 82% (81, 83%) with co-therapy (P < 0.001). Remission was obtained in 20% on monotherapy and 22% on co-therapy (P < 0.001); adjusted OR of 1.16 (1.07, 1.25). Remission rates at 12 months were similar in patients with/without peripheral arthritis.

Conclusion

This large European study of axial SpA patients showed similar one-year treatment outcomes for TNFi monotherapy and csDMARD co-therapy, although considerable heterogeneity across countries limited the identification of certain subgroups (e.g. peripheral arthritis) that may benefit from co-therapy.
DESIGN AND FABRICATION OF A PEDIATRIC THYROID PHANTOM FOR USE IN RADIO-IODINE UPTAKE MEASUREMENT, IMAGE QUALITY CONTROL AND DOSIMETRY
Authors: Sookhaki Saeed , Sina Sedigheh , Karimipourfard Mehrnoosh , Alavi Mehrosadat , Shoushtari Fereshteh Khodadadi
Published: March 2022

Estimating internal contamination from 131I for children in nuclear accidents is a crucial subject in the radiation protection field. Throughout this paper, an urgent and simple method was proposed for measuring 131I inside the pediatric thyroid gland by constructing a neck and thyroid phantom. For this purpose, CT scan images of healthy child’s thyroids were obtained, and the sizes of different parts were determined by a 3D slicer image processing software. Girls with the body surface area between 0.95 and 1.05 were involved in this study. The fabricated phantom is composed of 5 cylindrical slabs of 2-cm thickness, and several small holes were constructed for TLD dosemeters near the thyroid gland and all other parts of the neck. The phantom was constructed utilizing a 3D printer with acrylonitrile butadiene styrene plastic. The thyroid phantom was filled with radioiodine-131, and calibration curves were plotted for contamination estimation. A nodular thyroid phantom was also constructed. The nodular phantom or the resolution phantom has 4 removable parts containing cylindrical holes with diameters of 3, 6, 9 and 12 mm. These holes on the thyroid glands can be filled with different activities of radionuclides to serve as hot and cold spots for quality control of nuclear medicine images. The results show that the designed phantom is applicable in different fields such as nuclear image quality and resolution tests, dosimetry and iodine thyroid uptake estimation in nuclear medicine departments, and nuclear emergency monitoring.
Piloting a Mindfulness App for Use by Nursing Staff at Work
Authors: Fordham Keliy , Sorensen Jennifer
Published: March 2022

This article discusses the findings of a 5-week pilot using a mindfulness app among medical-surgical nursing staff in an acute care setting during a 12-hour shift. Informational sessions on compassion fatigue, mindfulness, and the process were implemented with leadership providing daily support. The postimplementation survey demonstrated increased calmness and reduced stress. Barriers identified involve perceived time constraints. Awareness is needed on compassion fatigue, interventions to combat, and modifications to promote the culture of self-care.
Primary and Secondary Syphilis Among Men Who Have Sex With Men and Women, 2010 to 2019
Authors: Learner Emily R. , Grey Jeremy A. , Bernstein Kyle , Kirkcaldy Robert D. , Torrone Elizabeth A.
Published: March 2022

The relative proportion of cases of primary and secondary syphilis among men who have sex with men and women reported through national case report data from 2010 to 2019 seemed stable overall and were stratified by race/ethnicity, region, and age group, but case counts increased.
The Price of Publishing: An Investigation of the Open Access Landscape in Plastic Surgery
Authors: Yesantharao Pooja S. , Long Chao , Sacks Justin M. , Lee Gordon K. , Nazerali Rahim S.
Published: March 2022

Background:

Open access publishing in plastic surgery has rapidly gained traction in the past decade. This study investigated the digital landscape of plastic surgery open access publishing.

Methods:

This was a cross-sectional bibliometric investigation of plastic surgery–focused journals. Three publication models were investigated: subscription-only journals, hybrid journals offering both paywalled and open access publishing, and open access–only journals.

Results:

Eighty-two journals were investigated. In 2010, open access journals comprised 18 percent of all plastic surgery journals online, subscription journals comprised 79 percent, and hybrid journals comprised 3 percent. Conversely, in 2020, open access journals comprised 55 percent of all journals, hybrid journals comprised 45 percent, and there were no subscription-only journals. Multivariable linear regression adjusting for article type/content demonstrated that open access articles from hybrid journals [beta coefficient, 1.3; F(4, 18) = 790; p = 0.05] and high-quality open access journals [beta coefficient, 0.9; F(4, 19) = 738; p = 0.04] were significantly positively associated with number of full-text views. Although impact factor and article processing charges were positively correlated [Pearson correlation coefficient: r(25) = 0.39, p = 0.04] for open access publishing, some high-quality open access journals were found to offer fee waivers/free publishing. Lastly, level of evidence offered by articles from open access versus hybrid journals differed.

Conclusions:

Overall, this study highlighted important distinctions between trustworthy and predatory journals offering open access publishing in plastic surgery. Open access publishing in trustworthy sources offers greater visibility and is not necessarily cost-prohibitive, but some open access journals can be limited in scope (i.e., less coverage of subspecialty topics) and quality of content. Study findings were used to generate recommendations for navigating open access publishing in plastic surgery.
Comparative Effectiveness Analysis of Resorbable Synthetic Onlay and Biologic Intraperitoneal Mesh for Abdominal Wall Reconstruction: A 2-Year Match-Paired Analysis
Authors: Othman Sammy , Christopher Adrienne , Patel Viren , Jia Hanna , Mellia Joseph A. , Kovach Stephen J. , Fischer John P.
Published: March 2022

Background:

Abdominal wall reconstruction persists as a challenging surgical issue with a multitude of management strategies available. The aim of this study was to examine the efficacy of resorbable synthetic mesh onlay plane against biologic mesh in the intraperitoneal plane.

Methods:

A single-center, two-surgeon, 5-year retrospective review (2014 to 2019) was performed examining subjects who underwent abdominal wall reconstruction in the onlay plane with resorbable synthetic mesh or in the intraperitoneal plane with biologic mesh. A matched paired analysis was conducted. Data examining demographic characteristics, intraoperative variables, postoperative outcomes, and costs were analyzed.

Results:

Eighty-eight subjects (44 per group) were identified (median follow-up, 24.5 months). The mean age was 57.7 years, with a mean body mass index of 30.4 kg/m2. The average defect size was 292 ± 237 cm2, with most wounds being clean-contaminated (48.9 percent) and 55 percent having failed prior repair. Resorbable synthetic mesh onlay subjects were significantly less likely (4.5 percent) to experience recurrence compared to biologic intraperitoneal mesh subjects (22.7 percent; p < 0.026). In addition, mesh onlay suffered fewer postoperative surgical-site occurrences (18.2 percent versus 40.9 percent; p < 0.019) and required fewer procedural interventions (11.4 percent versus 36.4 percent; p < 0.011), and was also associated with significantly lower total costs ($16,658 ± $14,930) compared to biologic intraperitoneal mesh ($27,645 ± $16,864; p < 0.001).

Conclusions:

Abdominal wall reconstruction remains an evolving field, with various techniques available for treatment. When faced with hernia repair, resorbable synthetic mesh in the onlay plane may be preferable to biologic mesh placed in the intraperitoneal plane because of lower long-term recurrence rates, surgical-site complications, and costs.

CLINICAL QUESTION/LEVEL OF EVIDENCE:

Therapeutic, III.
Adjunctive Nonpharmacologic Interventions for the Management of Burn Pain: A Systematic Review
Authors: Gasteratos Konstantinos , Papakonstantinou Menelaos , Man Angela , Babatsikos Emmanouil , Tamalonis Albina , Goverman Jeremy
Published: March 2022

Background:

The conventional way of treating burn victims with mainstream pain control modalities is costly and has many negative side effects. In this study, the authors aim to present the findings from the major clinical trials on three nonpharmacologic interventions—hypnosis, virtual/augmented reality, and yoga—as supplements to conventional pain regimens for burn management.

Methods:

A computerized literature search was conducted of the PubMed and ClinicalTrials.gov databases in April of 2020. The online screening process was performed by two independent reviewers with the Covidence tool. The protocol was reported using the Preferred Reporting Items for Systematic Review and Meta-Analyses, and it was registered at the International Prospective Register of Systematic Reviews of the National Institute for Health Research.

Results:

The search yielded 254 articles from 1955 to 2020. Fifty-eight studies met the authors’ inclusion criteria. Yoga reduced cognitive and somatic anxiety in burn survivors, and improved body image. Virtual reality is effective in pain reduction in both the pediatric and the adult burn population, and in faster burn wound reepithelialization. Hypnosis has similar results regarding reducing pain quality and anxiety in burn patients undergoing burn wound care and dressing changes but was not found to significantly accelerate the healing process.

Conclusions:

Nonpharmacologic interventions are not a substitute for conventional analgesics; however, they could help patients have better control over their pain, greater self-esteem, and less postburn traumatic experiences. Burn care centers should consider nonpharmacologic interventions to improve patient satisfaction and their participation in the treatment and rehabilitation process.
Impact of Single Eyelid on Superior Visual Field
Authors: Kitazawa Takeshi , Yuzuriha Shunsuke
Published: March 2022

A puffy eyelid without a crease, also known as single eyelid, is a common characteristic in East Asians. Existence of a lid crease is generally considered an aesthetic concern for both patients and surgeons, and postoperative evaluations have mainly focused on the appearance of the eye. The aim of this study was to clarify the functionality of the superior visual field (SVF) with single eyelid.

This prospective cohort study compared edge of the upper eyelid to central corneal light reflex distance (edge reflex distance [ERD]) preoperatively and postoperatively and examined the SVF, as measured by Goldmann perimetry, in single-eyelid patients who underwent blepharoplasty.

Twenty patients (40 eyelids) with a median age of 21 years were examined. The median preoperative and postoperative ERDs were 1.45 and 3.4 mm, respectively. The median areas of the SVF preoperatively and postoperatively were 34,443 and 50,796 degrees2, respectively. Although a positive correlation existed between preoperative ERD and SVF, no correlation was observed between postoperative ERD and SVF.

The SVF of the single eyelid is narrower than that of the double eyelid, even under circumstances of equivalent palpebral fissure height. The single eyelid commonly found in East Asian populations is associated with both cosmetic and functional issues.
Innovating for a Safe Simulation Challenge During a Pandemic: An Avatar Simulation Concept
Authors: Philippon Anne-Laure , Legros Pauline , Grattery Fabien , Leygue Alexandra , Pierrot Virginie , Faucher Sébastien , Khoury Abdo , Pornin Antoine , Truchot Jennifer , Bouilleau Guillem
Published: March 2022

Summary Statement

We present a new simulation-based challenge (Sim’Cup) concept, created in response to the COVID-19 pandemic. It took place in 2020, during the European Society of Emergency Medicine and the Societé Française de Médecine d’Urgence (SFMU) conferences. Usually, during the conferences, a Sim’Cup is held with onsite participants who are involved in a consecutive series of face-to-face simulations organized in 2 qualifying rounds, followed by a final round. When congresses were transformed into online events, the Sim’Cup had to evolve into a virtual format as well. We developed the e-Sim’Cup concept as follows: participants staying safely at home, piloting the trainers, as if they were their own avatar, in a simulation room with a full-scale high-fidelity manikin (Gaumard, Laerdal) using real-time scenarios. Participants gave instructions to the avatars through a smartphone and via a website. Each team participated in 2 scenarios. At the end of each scenario, teams had to undergo a self-debriefing, followed by a short debriefing with the organizers. Twenty-seven participants divided into 9 teams participated in 1 of the 2 e-Sim’Cup events.

We evaluated the impact of this approach using the Educational Practices Questionnaire, and we also analyzed the participants’ perception of their satisfaction and their feelings of improvement with this virtual format. Moreover, we conducted qualitative analyses of the self-debriefings. Thirteen participants filled out the questionnaire, giving a combined high Educational Practices Questionnaire score [72 (66.5–77) of 80], which reflects the presence of educational best practices during the e-Sim’Cups. They appreciated the adjusted Sim’Cup format and believed that they were able to improve their communication, clinical skills, and self-confidence. The qualitative analysis suggested that the approach was perceived as immersive by the 27 participants, with some challenges due to technical problems but an overall feeling of improvement regarding their crisis resource management skills. The hybrid remote simulation concept satisfied the participants who believed that it improved important skills in emergency medicine. The increasing number of remote activities and conferences lead us to believe that our e-Sim’Cup concept can be easily reproducible in any simulation center, as it requires only the application of the educational concept and either the use of the website or the use of some widely available technical devices.
Do not forget the platelets: The independent impact of red blood cell to platelet ratio on mortality in massively transfused trauma patients
Authors: Dorken Gallastegi Ander , Naar Leon , Gaitanidis Apostolos , Gebran Anthony , Nederpelt Charlie J. , Parks Jonathan J. , Hwabejire John O. , Fawley Jason , Mendoza April E. , Saillant Noelle N. , Fagenholz Peter J. , Velmahos George C. , Kaafarani Haytham M.A.
Published: March 2022

BACKGROUND

Balanced blood component administration during massive transfusion is standard of care. Most literature focuses on the impact of red blood cell (RBC)/fresh frozen plasma (FFP) ratio, while the value of balanced RBC:platelet (PLT) administration is less established. The aim of this study was to evaluate and quantify the independent impact of RBC:PLT on 24-hour mortality in trauma patients receiving massive transfusion.

METHODS

Using the 2013 to 2018 American College of Surgeons Trauma Quality Improvement Program database, adult patients who received massive transfusion (≥10 U of RBC/24 hours) and ≥1 U of RBC, FFP, and PLT within 4 hours of arrival were retrospectively included. To mitigate survival bias, only patients with consistent RBC:PLT and RBC:FFP ratios between 4 and 24 hours were analyzed. Balanced FFP or PLT transfusions were defined as having RBC:PLT and RBC:FFP of ≤2, respectively. Multivariable logistic regression was used to compare the independent relationship between RBC:FFP, RBC:PLT, balanced transfusion, and 24-hour mortality.

RESULTS

A total of 9,215 massive transfusion patients were included. The number of patients who received transfusion with RBC:PLT >2 (1,942 [21.1%]) was significantly higher than those with RBC:FFP >2 (1,160 [12.6%]) (p < 0.001). Compared with an RBC:PLT ratio of 1:1, a gradual and consistent risk increase was observed for 24-hour mortality as the RBC:PLT ratio increased (p < 0.001). Patients with both FFP and PLT balanced transfusion had the lowest adjusted risk for 24-hour mortality. Mortality increased as resuscitation became more unbalanced, with higher odds of death for unbalanced PLT (odds ratio, 2.48 [2.18–2.83]) than unbalanced FFP (odds ratio, 1.66 [1.37–1.98]), while patients who received both FFP and PLT unbalanced transfusion had the highest risk of 24-hour mortality (odds ratio, 3.41 [2.74–4.24]).

CONCLUSION

Trauma patients receiving massive transfusion significantly more often have unbalanced PLT rather than unbalanced FFP transfusion. The impact of unbalanced PLT transfusion on 24-hour mortality is independent and potentially more pronounced than unbalanced FFP transfusion, warranting serious system-level efforts for improvement.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.
Sex determination and sex chromosome evolution in land plants
Authors: Renner Susanne S. , Müller Niels A.
Published: March 2022

Linnaeus's very first opus, written when he was 22 years old, dealt with the analogy that exists between plants and animals in how they ‘propagate their species’, and a revised version with a plate depicting the union of male and femaleMercurialis annuaplants became a foundational text on the sexuality of plants. The question how systems with separate males and females have evolved in sedentary organisms that appear ancestrally bisexual has fascinated biologists ever since. The phenomenon, termed dioecy, has important consequences for plant reproductive success and is of commercial interest since it affects seed quality and fruit production. This theme issue presents a series of articles that synthesize and challenge the current understanding of how plants achieve dioecy. The articles deal with a broad set of taxa, includingCoccinia,Ginkgo,Mercurialis,Populus,RumexandSilene, as well as overarching topics, such as the field's terminology, analogies with animal sex determination systems, evolutionary pathways to dioecy, dosage compensation, and the longevity of the two sexes. In this introduction, we focus on four topics, each addressed by several articles from different angles and with different conclusions. Our highlighting of unclear or controversial issues may help future studies to build on the current understanding and to ask new questions that will expand our knowledge of plant sexual systems.

This article is part of the theme issue ‘Sex determination and sex chromosome evolution in land plants’.
Some sexual consequences of being a plant
Authors: Cronk Quentin
Published: March 2022

Plants have characteristic features that affect the expression of sexual function, notably the existence of a haploid organism in the life cycle, and in their development, which is modular, iterative and environmentally reactive. For instance, primary selection (the first filtering of the products of meiosis) is via gametes in diplontic animals, but via gametophyte organisms in plants. Intragametophytic selfing produces double haploid sporophytes which is in effect a form of clonal reproduction mediated by sexual mechanisms. In homosporous plants, the diploid sporophyte is sexless, sex being only expressed in the haploid gametophyte. However, in seed plants, the timing and location of gamete production is determined by the sporophyte, which therefore has a sexual role, and in dioecious plants has genetic sex, while the seed plant gametophyte has lost genetic sex. This evolutionary transition is one that E.J.H. Corner called ‘the transference of sexuality’. The iterative development characteristic of plants can lead to a wide variety of patterns in the distribution of sexual function, and in dioecious plants poor canalization of reproductive development can lead to intrasexual mating and the production of YY supermales or WW superfemales. Finally, plant modes of asexual reproduction (agamospermy/apogamy) are also distinctive by subverting gametophytic processes.

This article is part of the theme issue ‘Sex determination and sex chromosome evolution in land plants’.
The contributions of Nettie Stevens to the field of sex chromosome biology
Authors: Carey Sarah B. , Aközbek Laramie , Harkess Alex
Published: March 2022

The early 1900s delivered many foundational discoveries in genetics, including re-discovery of Mendel's research and the chromosomal theory of inheritance. Following these insights, many focused their research on whether the development of separate sexes had a chromosomal basis or if instead it was caused by environmental factors. It is Dr Nettie M. Stevens'Studies in spermatogenesis(1905) that provided the unequivocal evidence that the inheritance of the Y chromosome initiated male development in mealworms. This result established that sex is indeed a Mendelian trait with a genetic basis and that the sex chromosomes play a critical role. In Part II ofStudies in spermatogenesis(1906), an XY pair was identified in dozens of additional species, further validating the function of sex chromosomes. Since this formative work, a wealth of studies in animals and plants have examined the genetic basis of sex. The goal of this review is to shine a light again on Stevens’Studies in spermatogenesisand the lasting impact of this work. We additionally focus on key findings in plant systems over the last century and open questions that are best answered, as in Stevens' work, by synthesizing across many systems.

This article is part of the theme issue ‘Sex determination and sex chromosome evolution in land plants’.
ARR17 controls dioecy in
Populus
by repressing B-class MADS-box gene expression
Authors: Leite Montalvão Ana P. , Kersten Birgit , Kim Gihwan , Fladung Matthias , Müller Niels A.
Published: March 2022

The number of dioecious species for which the genetic basis of sex determination has been resolved is rapidly increasing. Nevertheless, the molecular mechanisms downstream of the sex determinants remain largely elusive. Here, by RNA-sequencing early-flowering isogenic aspen (
Populus tremula
) lines differing exclusively for the sex switch gene
ARR17
, we show that a narrowly defined genetic network controls differential development of female and male flowers. Although
ARR17
encodes a type-A response regulator supposedly involved in cytokinin (CK) hormone signalling, clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9-mediated
arr17
knockout only affected the expression of a strikingly small number of genes, indicating a specific role in the regulation of floral development rather than a generic function in hormone signalling. Notably, the
UNUSUAL FLORAL ORGANS
(
UFO
) gene, encoding an F-box protein acting as a transcriptional cofactor with
LEAFY
(
LFY
) to activate B-class MADS-box gene expression, and the B-class gene
PISTILLATA
(
PI
), necessary for male floral organ development, were strongly de-repressed in the
arr17
CRISPR mutants. Our data highlight a CK-independent role of the poplar response regulator ARR17 and further emphasize the minimal differences between female and male individuals.

This article is part of the theme issue ‘Sex determination and sex chromosome evolution in land plants’.
Dosage compensation evolution in plants: theories, controversies and mechanisms
Authors: Muyle Aline , Marais Gabriel A. B. , Bačovský Václav , Hobza Roman , Lenormand Thomas
Published: March 2022

In a minority of flowering plants, separate sexes are genetically determined by sex chromosomes. The Y chromosome has a non-recombining region that degenerates, causing a reduced expression of Y genes. In some species, the lower Y expression is accompanied by dosage compensation (DC), a mechanism that re-equalizes male and female expression and/or brings XY male expression back to its ancestral level. Here, we review work on DC in plants, which started as early as the late 1960s with cytological approaches. The use of transcriptomics fired a controversy as to whether DC existed in plants. Further work revealed that various plants exhibit partial DC, including a few species with young and homomorphic sex chromosomes. We are starting to understand the mechanisms responsible for DC in some plants, but in most species, we lack the data to differentiate between global and gene-by-gene DC. Also, it is unknown why some species evolve many dosage compensated genes while others do not. Finally, the forces that drive DC evolution remain mysterious, both in plants and animals. We review the multiple evolutionary theories that have been proposed to explain DC patterns in eukaryotes with XY or ZW sex chromosomes.

This article is part of the theme issue ‘Sex determination and sex chromosome evolution in land plants’.
Recurrent allopolyploidization, Y-chromosome introgression and the evolution of sexual systems in the plant genus
Mercurialis
Authors: Gerchen J. F. , Veltsos P. , Pannell J. R.
Published: March 2022

The plant genus
Mercurialis
includes dioecious, monoecious and androdioecious species (where males coexist with hermaphrodites). Its diversification involved reticulate evolution via hybridization and polyploidization. The Y chromosome of the diploid species
Mercurialis annua
shows only mild signs of degeneration. We used sequence variation at a Y-linked locus in several species and at multiple autosomal and pseudoautosomal loci to investigate the origin and evolution of the Y chromosome across the genus. Our study provides evidence for further cases of allopolyploid speciation. It also reveals that all lineages with separate sexes (with one possible exception) share the same ancestral Y chromosome. Surprisingly, males in androdioecious populations of hexaploid
M. annua
carry a Y chromosome that is not derived from either of its two putative progenitor lineages but from a more distantly related perennial dioecious lineage via introgression. These results throw new light on the evolution of sexual systems and polyploidy in
Mercurialis
and secure it as a promising model for further study of plant sex chromosomes.

This article is part of the theme issue ‘Sex determination and sex chromosome evolution in land plants’.
Adaptive changes of the autosomal part of the genome in a dioecious clade of
Silene
Authors: Zluvova Jitka , Kubat Zdenek , Hobza Roman , Janousek Bohuslav
Published: March 2022

The genus
Silene
brings many opportunities for the study of various processes involved in the evolution of dioecy and young sex chromosomes. Here we focus on a dioecious clade in
Silene
subgenus
Silene
and closely related species. This study provides improved support for monophyly of this clade (based on inclusion of further dioecious species) and a new estimate of its age (
ca
2.3 million years). We observed a rise in adaptive evolution in the autosomal and pseudoautosomal parts of the genome on the branch where dioecy originated. This increase is not a result of the accumulation of sexually antagonistic genes in the pseudoautosomal region. It is also not caused by the coevolution of genes acting in mitochondria (despite the possibility that dioecy along this branch could have evolved from a nucleo-cytoplasmic male sterility-based system). After considering other possibilities, the most parsimonious explanation for the increase seen in the number of positively selected codons is the adaptive evolution of genes involved in the adaptation of the autosomal part of the genome to dioecy, as described in Charnov's sex-allocation theory. As the observed coincidence cannot prove causality, studies in other dioecious clades are necessary to allow the formation of general conclusions.

This article is part of the theme issue ‘Sex determination and sex chromosome evolution in land plants’.
The evolution of huge Y chromosomes inCoccinia grandisand its sister,Coccinia schimperi
Authors: Janousek Bohuslav , Gogela Roman , Bacovsky Vaclav , Renner Susanne S.
Published: March 2022

Microscopically dimorphic sex chromosomes in plants are rare, reducing our ability to study them. One difficulty has been the paucity of cultivatable species pairs for cytogenetic, genomic and experimental work. Here, we study the newly recognized sistersCoccinia grandisandCoccinia schimperi, both with large Y chromosomes as we here show forCo. schimperi. We built genetic maps for male and femaleCo. grandisusing a full-sibling family, inferred gene sex-linkage, and, withCo. schimperitranscriptome data, tested whether X- and Y-alleles group by species or by sex. Most sex-linked genes for which we could include outgroups grouped the X- and Y-alleles by species, but some 10% instead grouped the two species' X-alleles. There was no relationship between XY synonymous-site divergences in these genes and gene position on the non-recombining part of the X, suggesting recombination arrest shortly before or after species divergence, here dated to about 3.6 Ma.Coccinia grandisandCo. schimperiare the species pair with the most heteromorphic sex chromosomes in vascular plants (the condition in their sister remains unknown), and future work could use them to study mechanisms of Y chromosome enlargement and parallel degeneration, or to test Haldane's rule about lower hybrid fitness in the heterogametic sex.

This article is part of the theme issue ‘Sex determination and sex chromosome evolution in land plants’.
The distribution of sexual function in the flowering plant: from monoecy to dioecy
Authors: Cronk Quentin
Published: March 2022

In flowering plants, male and female functions are usually closely associated in the same flowers, as predicted by resource allocation theory. However, the benefits of outbreeding can lead to unisexual flowers and the physiological control of their distribution across the plant (monoecy). Monoecy is thought to be a major route to dioecy (separation of sexual function of different individuals). The developmental and functional problems associated with unisexual flowers may thus be solved at the level of the evolution of monoecy. Consequently, the evolution of dioecy from monoecy requires mutations in only a single gene. Here various scenarios (conceptual models) are presented for the evolution of monoecy and dioecy, including scenarios consistent with known cases of single-gene control of dioecy, such as inPopulus, and the artificial breeding of dioecy from monoecy experimentally achieved inZeaandCucumis. Attention is also drawn here to the phenomenon of pleogamy, the minor or occasional occurrence of additional sex morphs within a species, which may provide important information about the genetic and developmental control of various sexual systems.

This article is part of the theme issue ‘Sex determination and sex chromosome evolution in land plants’.
Alicyclobacillus curvatus sp. nov. and Alicyclobacillus mengziensis sp. nov., two acidophilic bacteria isolated from acid mine drainage
Authors: Jiang Zhen , Wu Dildar , Liang Zong-Lin , Li Xiu-Tong , Huang Ye , Zhou Nan , Liu Zheng-Hua , Zhang Guang-Ji , Jia Yan , Yin Hua-Qun , Liu Shuang-Jiang , Jiang Cheng-Ying
Published: March 2022

Two acidophilic strains, designated as ALEF1T and S30H14T, were isolated from acid mine drainage sediment. Cells of both strains were Gram-stain-positive, aerobic, endospore-forming rods. Strains ALEF1T and S30H14T were acidophilic and mesophilic, the former grew at 20–40 °C (optimum, 30 °C) and pH 2.5–4.5 (optimum, pH 3.5), while the latter grew at 20–45 °C (optimum, 30 °C) and pH 2.0–5.5 (optimum, pH 4.5). The 16S rRNA gene-based sequence analysis revealed that strains ALEF1T and S30H14T belonged to the genus

Alicyclobacillus

, and were phylogenetically close to

Alicyclobacillus ferrooxydans

TC-34T with 97.1 and 97.4% similarity, respectively. The similarity between the two novel strains was 98.6 %. The average nucleotide identity value between the genome sequences of ALEF1T and S30H14T was 79.5 %, and that between each of the two isolates and

A. ferrooxydans

TC-34T were 72.0 and 74.3 %. In addition, the digital DNA–DNA hybridization value between ALEF1T and S30H14T was 24.9 %, between strain ALEF1T and

A. ferrooxydans

TC-34T was 21.7 %, and between S30H14T and

A. ferrooxydans

TC-34T was 26.3 %, far below the interspecies threshold. Both strains could utilize diverse carbon sources for heterotrophic growth; strain ALEF1T could utilize ferrous iron as the energy source for autotrophic growth. Menaquinone 7 was the only quinone detected in either strain. Both strains contained anteiso-C15 : 0 and anteiso-C17 : 0, while ω-alicyclic fatty acids were not detected. Based on their phylogenetic positions, as well as phenotypic and genomic data, it is considered that strains ALEF1T and S30H14T represent two novel species within the genus

Alicyclobacillus

, for which the names Alicyclobacillus curvatus sp. nov. (type strain ALEF1T=CGMCC 1.17055T=KCTC 43124T) and Alicyclobacillus mengziensis sp. nov. (S30H14T=CGMCC 1.17050T=KCTC 43125T) are proposed.
Longitudinal brain age prediction and cognitive function after stroke
Authors: Aamodt Eva B. , Alnæs Dag , de Lange Ann-Marie G. , Aam Stina , Schellhorn Till , Saltvedt Ingvild , Beyer Mona K. , Westlye Lars T.
Published: March 2022

Background

Advanced age and poor brain health have been associated with higher risk for more severe clinical and cognitive outcomes following stroke, but more accurate models for clinical prediction are needed. Machine learning based on brain scans can be used to estimate brain age of individual patients, and the corresponding difference from chronological age, the brain age gap (BAG) has been investigated in a range of clinical conditions. Yet, the predictive value for post stroke NCD has not been established. To this end, using longitudinal data we aimed to investigate the association between BAG and post-stroke neurocognitive disorder (NCD) over time.

Methods

269 stroke survivors (55.4% women, mean (SD) age = 71 (11) years) were included from the Norwegian Cognitive Impairment After Stroke (Nor-COAST) study. MRI and clinical data were collected shortly after the acute stroke (neuropsychological data first after 3 months) and at 18- and 36 months follow-up. The brain age model was trained in an independent sample using established protocols based on machine learning and brain structural features from Freesurfer and applied to the current dataset. We used linear mixed effects (LME) models and survival analysis to assess the associations between cognitive status and longitudinal brain age.

Results

LMEs revealed a main effect of BAG on post stroke NCD across time, confirming our main hypothesis that a younger appearing brain may protect against post stroke NCD. For patients with no NCD at baseline, survival analysis suggested that higher baseline BAG was associated with higher risk of post stroke NCD at 18 and 36 months.

Conclusion

A younger appearing brain is associated with lower risk of post stroke NCD up to 36 months after a stroke, even among those showing no evidence of impairments 3 months after hospital admission. Brain age prediction based on brain scans provides a reliable assessment of brain structure and is sensitive to post stroke NCD with predictive value for cognitive decline among patients with no impairment at the initial assessment.
Social stressors associated with age-related T lymphocyte percentages in older US adults: Evidence from the Health and Retirement Study
Authors: Klopack Eric T. , Crimmins Eileen M. , Cole Steve W. , Seeman Teresa E. , Carroll Judith E.
Published: March 2022

Exposure to stress is a well-established risk factor of poor health and accelerated aging. Immune aging, including declines in naive and increases in late memory and terminally differentiated T cells, plays an important role in immune health and tissue specific aging, and may contribute to the observed elevated risk for poor health among those who experience high psychosocial stress. However, past data have been limited in estimating the contribution of life stress to the development of accelerated immune aging and investigating mediators such as lifestyle and CMV infection, that might be useful points of intervention. The current study utilizes a national sample of 5744 US adults over the age of 50 to assess the relationship of social stress (viz., everyday discrimination, stressful life events, lifetime discrimination, life trauma, and chronic stress) with flow cytometric estimates of immune aging, including naive and terminally differentiated T cell percentages and the ratio of CD4+to CD8+T cells. Experiencing life trauma and chronic stress was related to a lower percentage of CD4+naive T cells. Higher everyday discrimination, lifetime discrimination, and chronic stress were each associated with a greater percentage of terminally differentiated CD4+T cells. Stressful life events, high lifetime discrimination, and life trauma were related to a lower percentage of CD8+naive T cells. Stressful life events, high lifetime discrimination and chronic stress were associated with a higher percentage terminally differentiated CD8+T cells. High lifetime discrimination and chronic stress was related to a lower CD4+:CD8+ratio. Lifestyle factors and cytomegalovirus (CMV) seropositivity partially reduced these effects. Results identify psychosocial stress as a contributor to accelerating immune aging by decreasing naive and increasing senescent T cells.
Clinical and Computational Speech Measures are Associated with Social Cognition in Schizophrenia Spectrum Disorders
Authors: Tang Sunny X. , Cong Yan , Nikzad Amir H. , Mehta Aarush , Cho Sunghye , Hänsel Katrin , Berretta Sarah , Kane John , Malhotra Anil K
Published: March 2022

In this study, we compared three domains of social cognition (emotion processing, mentalization, and attribution bias) to clinical and computational language measures in 63 participants with schizophrenia spectrum disorders. Based on the active inference model for discourse, we hypothesized that emotion processing and mentalization, but not attribution bias, would be related to language disturbances. Clinical ratings for speech disturbance assessed disorganized and underproductive dimensions. Computational features included speech graph metrics, use of modal verbs, use of first-person pronouns, cosine similarity of adjacent utterances, and measures of sentiment; these were represented by four principal components characterizing content-rich speech, insular speech, local coherence, and affirmative speech. We found that higher clinical ratings for disorganized speech predicted greater impairments in both emotion processing and mentalization, and that these relationships remained significant when accounting for demographic variables, overall psychosis symptoms, and verbal ability. Similarly, computational features reflecting insular speech also consistently predicted greater impairment in emotion processing. There were notable trends for underproductive speech and decreased content-rich speech predicting mentalization ability. Exploratory longitudinal analyses in a small subset of participants (n=17) found that improvements in both emotion processing and mentalization were predicted by improvements in disorganized speech. Attribution bias did not demonstrate strong relationships with language measures. Altogether, our findings are consistent with the active inference model of discourse and suggest greater emphasis on treatments that target social cognitive and language systems.
Investigating the temporal pattern of neuroimaging-based brain age estimation as a biomarker for Alzheimer’s Disease related neurodegeneration
Authors: Taylor Alexei , Zhang Fengqing , Niu Xin , Heywood Ashley , Stocks Jane , Feng Gangyi , Popuri Karteek , Beg Mirza Faisal , Wang Lei ,   the Alzheimer’s Disease Neuroimaging Initiative
Published: March 2022

Neuroimaging-based brain-age estimation via machine learning has emerged as an important new approach for studying brain aging. The difference between one’s estimated brain age and chronological age, the brain age gap (BAG), has been proposed as an Alzheimer’s Disease (AD) biomarker. However, most past studies on the BAG have been cross-sectional. Identifying how an individual’s BAG temporal pattern changes over time would enable improved prediction of clinical outcome based on neurophysiological changes and better understanding of AD progression. To fill this gap, our study conducted predictive modeling using large neuroimaging data with up to 8 years of follow-up to examine the temporal patterns of the BAG’s trajectory and how it varies by subject-level characteristics and disease status. To the best of our knowledge, this is the first effort to take a longitudinal approach to investigate the pattern and rate of change in BAG over time in individuals who progress from mild cognitive impairment (MCI) to clinical AD. Combining multimodal imaging data in a support vector regression model to estimate brain age yielded improved performance than single modality. Multilevel modeling results showed the BAG followed a linear increasing trajectory with a significantly faster rate in individuals with MCI who progressed to AD compared to cognitively normal or MCI individuals who did not progress. The dynamic changes in the BAG during AD progression were further moderated by gender and APOε4 carriership. Findings demonstrate the BAG as a potential biomarker for understanding individual specific temporal patterns related to AD progression.
Task feedback suggests a post-perceptual component to serial dependence
Authors: Fulvio Jacqueline M. , Rokers Bas , Samaha Jason
Published: March 2022

Decisions across a range of perceptual tasks are biased toward past stimuli. Such serial dependence is thought to be an adaptive low-level mechanism that promotes perceptual stability across time. However, recent studies suggest post-perceptual mechanisms may also contribute to serially-biased responses, calling into question a single locus of serial dependence and the nature of integration of past and present sensory inputs. We measured serial dependence in the context of a 3D motion perception task where uncertainty in the sensory information varied substantially from trial to trial. We found that serial dependence varied with stimulus properties that impact sensory uncertainty on the current trial. Reduced stimulus contrast was associated with an increased bias toward the previous trial’s stimulus direction. Critically, performance feedback, which reduced sensory uncertainty, abolished serial dependence. These results provide clear evidence for a post-perceptual locus of serial dependence in 3D motion perception and support the role of serial dependence as a response strategy in the face of substantial sensory uncertainty.
No evidence for asymmetric sperm deposition in a species with asymmetric male genitalia
Authors: van Gammeren Sanne , Lang Michael , Rücklin Martin , Schilthuizen Menno
Published: March 2022

Background

Asymmetric genitalia have repeatedly evolved in animals, yet the underlying causes for their evolution are mostly unknown. The fruitfly Drosophila pachea has asymmetric external genitalia and an asymmetric phallus with a right-sided gonopore. The complex of female and male genitalia is asymmetrically twisted during copulation and males adopt a right-sided copulation posture on top of the female. We wished to investigate if asymmetric male genital morphology and a twisted gentitalia complex may be associated with differential allocation of sperm into female sperm storage organs.

Methods

We examined the internal complex of female and male reproductive organs by micro-computed tomography using Synchrotron X-rays before, during and after copulation. In additon, we monitored sperm aggregation states and timing of sperm transfer during copulation by premature interruption of copulation at different time-points.

Results

The asymmetric phallus is located at the most caudal end of the female abdomen during copulation. The female reproductive tract, in particular the oviduct, re-arranges during copulation. It is narrow in virgin females and forms a broad vesicle at 20 min after the start of copulation. Sperm transfer into female sperm storage organs (spermathecae) was only in a minority of examined copulation trials (13 / 64). Also, we found that sperm was mainly transferred early, at 2 - 4 min after the start of copulation. We did not detect a particular pattern of sperm allocation in the left or right spermathecae. Sperm adopted a granular or filamentous aggregation state in the female uterus and spermathecae, respectively.

Discussion

No evidence for asymmetric sperm deposition was identified that could be associated with asymmetric genital morphology or twisted complexing of genitalia. Male genital asymmetry may potentially have evolved as a consequence of a complex internal alignment of reproductive organs during copulation in order to optimize low sperm transfer rates.