bluuebunny/crossref_metadata_2025 huggingface dataset:
SELECTION FOR THE α-THALASSEMIA GENES
Authors: Yokoyama Shozo
Published: January 2021

Extremely high incidences of single and double deletions of α-globin genes are known among Asian populations. To study possible mechanisms for the maintenance of such deletions, mathematical analyses have been conducted. It has been shown that a stable polymorphism can be achieved easily through heterozygote advantage using deterministic models. The results strongly suggest that high incidences of single and double deletion of α-globin genes among Asian populations are maintained by some type of heterozygote advantage.
VIABILITY OF FEMALE GERM-LINE CELLS HOMOZYGOUS FOR ZYGOTIC LETHALS IN DROSOPHILA MELANOGASTER
Authors: Garcia-Bellido Antonio , Robbins Leonard G
Published: January 2021

We have analyzed the viability of different types of X chromosomes in homozygous clones of female germ cells. The chromosomes carried viable mutations, single-cistron zygotic-lethal and semi-lethal mutations, or small (about six chromosome band) deletions. Homozygous germ-line clones were produced by recombination in females heterozygous for an X-linked, dominant, agametic female sterile.

All the zygotic-viable mutants are also viable in germ cells. Of 16 deletions tested (uncovering a total of 93 bands) only 2 (of 4 and 5 bands) are germ-cell viable. Mutations in 15 lethal complementation groups in the zeste-white region were tested. When known, the most extreme alleles at each locus were tested. Only in five loci (33%) were the mutants viable in the germ line. Similar studies of the same deletions and point-mutant lethals in epidermal cells show that 42% of the bands and 77% of the lethal alleles are viable. Thus, germ-line cells have more stringent cell-autonomous genetic requirements than do epidermal cells.

The eggs recovered from clones of three of the germ-cell viable zw mutations gave embryos arrested early in embryogenesis, although genotypically identical embryos derived from heterozygous oogonia die as larvae or even hatch as adult escapers. For two genes, homozygosis of the mutations tested also caused embryonic arrest of heterozygous female embryos, and in one case, the eggs did not develop at all. Germ-line clones of one quite leaky mutation gave eggs that were indistinguishable from normal. The abundance of genes whose products are required for oogenesis, whose products are required in the oocyte, and whose activity is required during zygotic development is discussed.
LINKAGE MODIFICATION WITH MIXED RANDOM MATING AND SELFING: A NUMERICAL STUDY
Authors: Holsinger Kent E , Feldman Marcus W
Published: January 2021

Although recombination cannot increase under conditions of random mating or complete selfing in regimes of constant selection, with mixed random mating and selfing, selection for increased recombination can occur. For some fitness regimes there may be selection for reduced recombination with both low and high degrees of selfing but selection for increased recombination with moderate degrees of selfing. With some fitness regimes there is a historical effect: depending on which equilibrium a population starts from, there may be selection for either increased or decreased recombination. In other cases the direction of selection may be determined by the present state of individuals within the population. If recombination is already fairly limited, there may be selection for further reduction. If recombination is already fairly frequent, there may be selection for increased recombination. For certain symmetric viability systems there may be an intermediate value of the recombination fraction between 0 and 0.5 toward which the population will evolve. Although it is not yet possible to classify precisely those fitness matrices that can exhibit selection for increased recombination, it does appear that selection for increased recombination can occur only if at least two of the double homozygotes are less fit than would be expected on the basis of a comparison of the fitnesses of the single and double heterozygotes on an additive scale.
ON THE COMPONENTS OF SEGREGATION DISTORTION IN DROSOPHILA MELANOGASTER. II. DELETION MAPPING AND DOSAGE ANALYSIS OF THE SD LOCUS
Authors: Brittnacher John G , Ganetzky Barry
Published: January 2021

Segregation distorter (SD) chromosomes are preferentially transmitted to offspring from heterozygous SD/SD  + males owing to the induced dysfunction of the SD  +-bearing sperm. This phenomenon involves at least two major loci: the Sd locus whose presence is necessary for distortion to occur and the Rsp locus which acts as the site of Sd action. Several additional loci on SD chromosomes enhance distortion.—In a previous study deletions were used to map the Sd locus and to determine some of its properties. We have extended this analysis with the isolation and characterization of 14 new deletions in the Sd region. From our results we conclude (1) SD chromosomes contain a single Sd locus located in region 37D2-6 of the salivary gland chromosome map. Deletion of this locus in any of three SD chromosomes now studied results in complete loss of ability to distort a sensitive chromosome; (2) the reduced male fecundity observed in many homozygous SD or SDi/SDj combinations is due at least in part to the action of the Sd locus. The fecundity of these males can be substantially increased by deletion of one Sd locus. Thus, it is the presence of two doses of Sd rather than the absence of Sd  + that produces the lowered male fecundity in SD homozygotes; (3) Sd behaves as a neomorph, whereas Sd  +, if it exists at all, is amorphic with respect to segregation distortion; (4) these results support a model in which the Sd product is made in limiting amounts and the interaction of this product with the Rsp locus causes sperm dysfunction. The Sd product appears to act preferentially at Rsps (sensitive-Responder) but may also act at Rspi (insensitive-Responder).
ADAPTATION AT SPECIFIC LOCI. II. DEMOGRAPHIC AND BIOCHEMICAL ELEMENTS IN THE MAINTENANCE OF THE COLIAS PGI POLYMORPHISM
Authors: Watt Ward B
Published: January 2021

Demographically oriented sampling in the wild and biochemical study of allozymes in the laboratory have been used to probe maintenance of the phosphoglucose isomerase polymorphism of Colias butterflies.—The several alleles at this locus show negative or no covariation among their frequencies in the wild. This rules out Wahlund effects as a cause of observations of heterozygote excess at this locus in broods that fly as single cohorts. Unusually heavy mortality among adults, due to drought stress or other causes, can preclude manifestation of differential survivorship among phosphoglucose isomerase genotypes. In broods composed of overlapping cohorts, heterozygote deficiency, apparently due to Wahlund effects in time as cohorts of different survivorship experience mix, can be found. Heterozygotes at this locus fly under a broader range of weather conditions than other genotypes.—Previously detected kinetic differentiation among the genotypes extends in greater magnitude to the glycolytic reaction direction, as well as to a broader range of test conditions than examined before. The heterozygote 3/4 is strikingly heterotic for several measures of kinetic functional effectiveness. Other heterozygotes are sometimes heterotic, more often intermediate (but not exactly so, nor additive in any sense) in properties between homozygotes.—Predictions are made from the biochemical analysis and from the insects' thermal ecology concerning distributions of the genotypes in the wild. Some agree with facts already established. Others are tested and confirmed from data already on hand. Still others are to be tested as reported in an accompanying paper.—All available evidence points to a combination of heterozygote advantage and fluctuating-environment selection as responsible for maintaining this polymorphism. There is considerable evidence for the operation of protein-structural constraint on the range of adaptations possible at this locus.
ISOLATION AND CHARACTERIZATION OF LIGHT-INSENSITIVE MUTANTS OF NEUROSPORA CRASSA
Authors: Paietta John , Sargent Malcolm L
Published: January 2021

As part of a genetic analysis of blue light photoreception in Neurospora, three mutants were isolated that do not exhibit photosuppression of circadian conidiation, i.e., they show periodic conidiation in constant light. The mutations have been given the designations lis-1, lis-2 and lis-3 ("light insensitive"). The three mutations segregate as single nuclear genes, are nonallelic and are recessive to wild type in heterokaryon tests. The linkage groups of the mutations are as follows: lis-1, I; lis-2, VI; and lis-3, V. The light -insensitive phenotype of the mutants is restricted to the photosuppression response; other responses such as photoinduced phase shifting of the conidiation rhythm and photoinduced carotenogenesis are not altered. The physiological or biochemical defects of the mutants have not been established, but they are not similar to previous reported cases (i.e., rib and poky) in which a reduction in light sensitivity has been observed.
SHOULD INDIVIDUAL FITNESS INCREASE WITH HETEROZYGOSITY?
Authors: Turelli Michael , Ginzburg Lev R
Published: January 2021

Natural selection influences not only gamete frequencies in populations but also the multilocus fitness structures associated with segregating gametes. In particular, only certain patterns of multilocus fitnesses are consistent with the maintenance of stable multilocus polymorphisms. This paper offers support for the proposition that, at stable, viability-maintained, multilocus polymorphisms, the fitness of a genotype tends to increase with the number of heterozygous loci it contains. Average fitness always increases with heterozygosity at stable product equilibria (i.e., those without linkage disequilibrium) maintained by either additive or multiplicative fitness schemes. Simulations suggest that it "generally" increases for arbitrary fitness schemes. The empirical literature correlating allozyme heterozygosity with fitness-correlated traits is discussed in the light of these and other theoretical results.
THE EFFECT OF mei-41 ON rDNA REDUNDANCY IN DROSOPHILA MELANOGASTER
Authors: Hawley R Scott , Tartof Kenneth D
Published: January 2021

The recombination and repair defective mutant, mei-41, exhibits three rather striking effects on the genetic properties and chromosomal stability of rDNA in Drosophila. First, mei-41 inhibits rDNA magnification. However, mei-9, another recombination and repair defective mutation has no similar effect. This indicates that magnification requires some, but not all, of the gene products necessary for meiotic exchange. Second, under magnifying conditions, mei-41 induces interchanges between the X rDNA and either arm of the Ybb  - chromosome. These interchanges occur at high frequency and are independent of rDNA orientation. Third, in mei-41 bb  +/Ybb  + males, bobbed mutants in the X, but not the Y, also arise at high frequency. Evidence suggests that these events involve the rDNA type I insertion. The recombination and repair defective properties of mei-41 together with our results regarding its unusual and specific effects involving rDNA are explained in a simple model that has general implications for chromosome structure.
TRANSPOSABLE ELEMENTS IN MENDELIAN POPULATIONS. I. A THEORY
Authors: Langley Charles H , Brookfield John F Y , Kaplan Norman
Published: January 2021

Transposable elements are DNA sequences, found throughout eukaryotes, that transpose replicatively and cause numerous genetic and developmental effects on their hosts. A model of the evolution of transposable elements in Mendelian populations is proposed. From its analysis, formulas for the mean copy number and frequency spectrum are obtained.
FREQUENCY DISTRIBUTION OF ESTERASE-5 ALLELES IN TWO POPULATIONS OF DROSOPHILA PSEUDOOBSCURA
Authors: Keith Tim Perri
Published: January 2021

Statistical tests comparing allele frequencies in natural populations with those predicted by various theories of genic variation depend critically on the accurate enumeration of alleles. This study used a series of five sequential electrophoretic conditions to characterize the allele frequency distributions of esterase-5 in two large population samples of Drosophila pseudoobscura from California. In Standard chromosome lines 12 electromorphs were discriminated using a single electrophoretic condition. When four additional criteria were used, the number of electromorphs increased to 41, 33 in one population and 22 in the other. Both populations had the same two alleles in high frequency, with other alleles present in frequencies of 6% or less. Although each population had a number of unique alleles, a χ2 contingency test demonstrated no significant genetic divergence between them. A statistical comparison of allele frequencies in both populations with that predicted by neutral models suggests that the individual and combined distributions deviate from neutrality in the direction of purifying selection.—Sex-Ratio chromosomes differed markedly from Standard chromosomes in both allelic content and diversity. In 32 Sex-Ratio chromosomes from one population only three alleles were found, all of which were detected under the initial "standard" electrophoretic conditions. Moreover, none of these alleles was found in the Standard chromosome lines.
ESTIMATION OF THE COANCESTRY COEFFICIENT: BASIS FOR A SHORT-TERM GENETIC DISTANCE
Authors: Reynolds John , Weir B S , Cockerham C Clark
Published: January 2021

A distance measure for populations diverging by drift only is based on the coancestry coefficient θ, and three estimators of the distance D = -ln(1 - θ) are constructed for multiallelic, multilocus data. Simulations of a monoecious population mating at random showed that a weighted ratio of single-locus estimators performed better than an unweighted average or a least squares estimator. Jackknifing over loci provided satisfactory variance estimates of distance values. In the drift situation, in which mutation is excluded, the weighted estimator of D appears to be a better measure of distance than others that have appeared in the literature.
SPECIFICITY OF TRANSPOSON Tn5 INSERTION
Authors: Berg Douglas E , Schmandt Margaret A , Lowe John B
Published: January 2021

Genetic mapping studies had shown that the bacterial transposon Tn5 can insert into many sites in a gene, but that some sites are preferred. To begin understanding Tn5's insertion specificity at the molecular level, we selected transpositions of Tn5 from the Escherichia coli chromosome to the plasmid pBR322 and analyzed the resultant pBR322::Tn5 plasmids by restriction endonuclease digestion and DNA sequencing. Seventy-five insertions in the tet gene were found at 28 sites including one major hotspot (with 21 insertions) and four lesser hotspots (with four to ten insertions each). All five hotspots are within the first 300 of the 1250-base pair (bp) tet gene. In contrast, 31 independent insertions in the amp gene were found in at least 27 distinct sites.—Tn5 generates 9 bp target sequence duplications when it transposes. Such transposon-induced duplications are generally taken to indicate that cleavages of complementary target DNA strands are made 9 bp apart during transposition. DNA sequence analysis indicated that GC base pairs occupy positions 1 and 9 in the duplications at each of the five hotspots examined, suggesting a GC-cutting preference during Tn5 transposition.
Heritability and family-based GWAS analyses of the N-acyl ethanolamine and ceramide plasma lipidome
Authors: McGurk Kathryn A , Williams Simon G , Guo Hui , Watkins Hugh , Farrall Martin , Cordell Heather J , Nicolaou Anna , Keavney Bernard D
Published: January 2021

Signalling lipids of the N-acyl ethanolamine (NAE) and ceramide (CER) classes have emerged as potential biomarkers of cardiovascular disease (CVD). We sought to establish the heritability of plasma NAEs (including the endocannabinoid anandamide) and CERs, to identify common DNA variants influencing the circulating concentrations of the heritable lipids, and assess causality of these lipids in CVD using 2-sample Mendelian randomization (2SMR). Nine NAEs and 16 CERs were analyzed in plasma samples from 999 members of 196 British Caucasian families, using targeted ultra-performance liquid chromatography with tandem mass spectrometry. All lipids were significantly heritable (h2 = 36–62%). A missense variant (rs324420) in the gene encoding the enzyme fatty acid amide hydrolase (FAAH), which degrades NAEs, associated at genome-wide association study (GWAS) significance (P < 5 × 10−8) with four NAEs (DHEA, PEA, LEA and VEA). For CERs, rs680379 in the SPTLC3 gene, which encodes a subunit of the rate-limiting enzyme in CER biosynthesis, associated with a range of species (e.g. CER[N(24)S(19)]; P = 4.82 × 10−27). We observed three novel associations between SNPs at the CD83, SGPP1 and DEGS1 loci, and plasma CER traits (P < 5 × 10−8). 2SMR in the CARDIoGRAMplusC4D cohorts (60 801 cases; 123 504 controls) and in the DIAGRAM cohort (26 488 cases; 83 964 controls), using the genetic instruments from our family-based GWAS, did not reveal association between genetically determined differences in CER levels and CVD or diabetes. Two of the novel GWAS loci, SGPP1 and DEGS1, suggested a casual association between CERs and a range of haematological phenotypes, through 2SMR in the UK Biobank, INTERVAL and UKBiLEVE cohorts (n = 110 000–350 000).
Marmosets: Welfare, Ethical Use, and IACUC/Regulatory Considerations
Authors: Colman Ricki J , Capuano Saverio , Bakker Jaco , Keeley Jo , Nakamura Katsuki , Ross Corinna
Published: January 2021

Use of marmosets in biomedical research has increased dramatically in recent years due, in large part, to their suitability for transgenic applications and utility as models for neuroscience investigations. This increased use includes the establishment of new colonies and involvement of people new to marmoset research. To facilitate the use of the marmoset as a research model, we provide an overview of issues surrounding the ethics and regulations associated with captive marmoset research, including discussion of the history of marmosets in research, current uses of marmosets, ethical considerations related to marmoset use, issues related to importation of animals, and recommendations for regulatory oversight of gene-edited marmosets. To understand the main concerns that oversight bodies have regarding captive biomedical research with marmosets, we developed a brief, 15-question survey that was then sent electronically to academic and biomedical research institutions worldwide that were believed to house colonies of marmosets intended for biomedical research. The survey included general questions regarding the individual respondent’s colony, status of research use of the colony and institutional oversight of both the colony itself and the research use of the colony. We received completed surveys from a total of 18 institutions from North America, Europe, and Asia. Overall, there appeared to be no clear difference in regulatory oversight body concerns between countries/regions. One difference that we were able to appreciate was that while biomedical research with marmosets was noted to be either stable or decreasing in Europe, use was clearly increasing elsewhere.
Goeritz Groups of Bridge Decompositions
Authors: Hirose Susumu , Iguchi Daiki , Kin Eiko , Koda Yuya
Published: January 2021

For a bridge decomposition of a link in the $3$-sphere, we define the Goeritz group to be the group of isotopy classes of orientation-preserving homeomorphisms of the $3$-sphere that preserve each of the bridge sphere and link setwise. After describing basic properties of this group, we discuss the asymptotic behavior of the minimal pseudo-Anosov entropies. We then give an application to the asymptotic behavior of the minimal entropies for the original Goeritz groups of Heegaard splittings of the $3$-sphere and the real projective space.
Summer-type hypersensitivity pneumonitis in a share house for foreigners in Japan
Authors: Sugimoto Hiroshi , Nakamura Shunsuke , Kajimoto Kazuhiro
Published: January 2021

Summer-type hypersensitivity pneumonitis commonly occurs in Japan during the warm and humid season, when the causative Trichosporon asahii flourish. The assessment of anti-T. asahii antibodies in patients with hypersensitivity pneumonitis without any obvious causative antigen may be useful even outside Japan.
MOVES – IV. Modelling the influence of stellar XUV-flux, cosmic rays, and stellar energetic particles on the atmospheric composition of the hot Jupiter HD 189733b
Authors: Barth P , Helling Ch , Stüeken E E , Bourrier V , Mayne N , Rimmer P B , Jardine M , Vidotto A A , Wheatley P J , Fares R
Published: January 2021

Hot Jupiters provide valuable natural laboratories for studying potential contributions of high-energy radiation to pre-biotic synthesis in the atmospheres of exoplanets. In this fourth paper of the Multiwavelength Observations of an eVaporating Exoplanet and its Star (MOVES) programme, we study the effect of different types of high-energy radiation on the production of organic and pre-biotic molecules in the atmosphere of the hot Jupiter HD 189733b. Our model combines X-ray and UV observations from the MOVES programme and 3D climate simulations from the 3D Met Office Unified Model to simulate the atmospheric composition and kinetic chemistry with the STAND2019 network. Also, the effects of galactic cosmic rays and stellar energetic particles are included. We find that the differences in the radiation field between the irradiated dayside and the shadowed nightside lead to stronger changes in the chemical abundances than the variability of the host star’s XUV emission. We identify ammonium (NH4+) and oxonium (H3O+) as fingerprint ions for the ionization of the atmosphere by both galactic cosmic rays and stellar particles. All considered types of high-energy radiation have an enhancing effect on the abundance of key organic molecules such as hydrogen cyanide (HCN), formaldehyde (CH2O), and ethylene (C2H4). The latter two are intermediates in the production pathway of the amino acid glycine (C2H5NO2) and abundant enough to be potentially detectable by JWST.
Compressive Shack–Hartmann wavefront sensor based on deep neural networks
Authors: Jia Peng , Ma Mingyang , Cai Dongmei , Wang Weihua , Li Juanjuan , Li Can
Published: January 2021

The Shack–Hartmann wavefront sensor is widely used to measure aberrations induced by atmospheric turbulence in adaptive optics systems. However, if strong atmospheric turbulence exists or the brightness of guide stars is low, the accuracy of wavefront measurements will be affected. In this work, we propose a compressive Shack–Hartmann wavefront sensing method. Instead of reconstructing wavefronts with slope measurements of all subapertures, our method reconstructs wavefronts with slope measurements of subapertures that have spot images with high signal-to-noise ratio. We further propose to use a deep neural network to accelerate the wavefront reconstruction speed. During the training stage of the deep neural network, we propose to add a drop-out layer to simulate the compressive sensing process, which could increase the development speed of our method. After training, the compressive Shack–Hartmann wavefront sensing method can reconstruct wavefronts at high spatial resolution with slope measurements from only a small number of subapertures. We integrate the straightforward compressive Shack–Hartmann wavefront sensing method with an image deconvolution algorithm to develop a high-order image restoration method. We use images restored by the high-order image restoration method to test the performance of our compressive Shack–Hartmann wavefront sensing method. The results show that our method can improve the accuracy of wavefront measurements and is suitable for real-time applications.
The nascent polypeptide in the 60S subunit determines the Rqc2-dependency of ribosomal quality control
Authors: Mizuno Masato , Ebine Shuhei , Shounai Okuto , Nakajima Shizuka , Tomomatsu Shota , Ikeuchi Ken , Matsuo Yoshitaka , Inada Toshifumi
Published: January 2021

Ribosome stalling at tandem CGA codons or poly(A) sequences activates quality controls for nascent polypeptides including ribosome-associated quality control (RQC) and no-go mRNA decay (NGD). In RQC pathway, Hel2-dependent uS10 ubiquitination and the RQC-trigger (RQT) complex are essential for subunit dissociation, and Ltn1-dependent ubiquitination of peptidyl-tRNA in the 60S subunit requires Rqc2. Here, we report that polytryptophan sequences induce Rqc2-independent RQC. More than 11 consecutive tryptophan residues induced RQC in a manner dependent on Hel2-mediated ribosome ubiquitination and the RQT complex. Polytryptophan sequence-mediated RQC was not coupled with CAT-tailing, and Rqc2 was not required for Ltn1-dependent degradation of the arrest products. Eight consecutive tryptophan residues located at the region proximal to the peptidyl transferase center in the ribosome tunnel inhibited CAT-tailing by tandem CGA codons. Polytryptophan sequences also induced Hel2-mediated canonical RQC-coupled NGD and RQC-uncoupled NGD outside the stalled ribosomes. We propose that poly-tryptophan sequences induce Rqc2-independent RQC, suggesting that CAT-tailing in the 60S subunit could be modulated by the polypeptide in the ribosome exit tunnel.
UV-A/B radiation rapidly activates photoprotective mechanisms in Chlamydomonas reinhardtii
Authors: Tokutsu Ryutaro , Fujimura-Kamada Konomi , Yamasaki Tomohito , Okajima Keisuke , Minagawa Jun
Published: January 2021

Conversion of light energy into chemical energy through photosynthesis in the chloroplasts of photosynthetic organisms is essential for photoautotrophic growth, and non-photochemical quenching (NPQ) of excess light energy prevents the generation of reactive oxygen species and maintains efficient photosynthesis under high light. In the unicellular green alga Chlamydomonas reinhardtii, NPQ is activated as a photoprotective mechanism through wavelength-specific light signaling pathways mediated by the phototropin (blue light) and ultra-violet (UV) light photoreceptors, but the biological significance of photoprotection activation by light with different qualities remains poorly understood. Here, we demonstrate that NPQ-dependent photoprotection is activated more rapidly by UV than by visible light. We found that induction of gene expression and protein accumulation related to photoprotection was significantly faster and greater in magnitude under UV treatment compared with that under blue- or red-light treatment. Furthermore, the action spectrum of UV-dependent induction of photoprotective factors implied that C. reinhardtii senses relatively long-wavelength UV (including UV-A/B), whereas the model dicot plant Arabidopsis (Arabidopsis thaliana) preferentially senses relatively short-wavelength UV (mainly UV-B/C) for induction of photoprotective responses. Therefore, we hypothesize that C. reinhardtii developed a UV response distinct from that of land plants.
The new role of musculoskeletal ultrasound in the treat-to-target management of juvenile idiopathic arthritis
Authors: Gohar Faekah , Windschall Daniel
Published: January 2021

This article reviews the role of musculoskeletal ultrasound (MSUS) for the diagnosis, monitoring and treat-to-target management of JIA. Technological advancements in MSUS allow more precise evaluation of arthritis, tenosynovitis and enthesitis versus clinical examination alone, which may assist treatment decisions. In adult studies, serum and synovial biomarkers have correlated with MSUS findings. Within paediatric rheumatology, significant developments in the definition of normal and pathology, a necessity for the future integration of MSUS into treat-to-target management, have already been reached or are underway, which in turn could allow tighter control of disease activity and earlier identification of treatment response and failure, bringing the goal of ‘precision medicine’ closer. Additionally, the utility of MSUS for the evaluation of subclinical disease remains an unexamined area of interest. ‘Ultrasound remission’ combined with clinical assessment and immunological markers could therefore potentially improve the treat-to-target management of JIA.
Asthma, severe acute respiratory syndrome coronavirus-2 and coronavirus disease 2019
Authors: Timberlake Dylan T. , Strothman Kasey , Grayson Mitchell H.
Published: January 2021

Purpose of review

In December 2019, a novel respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first described and named coronavirus disease 2019 (COVID-19). Although the knowledge base surrounding COVID-19 and SARS-CoV-2 has grown rapidly, significant gaps in our knowledge remain and inaccurate information continues to circulate. This review will discuss the interaction between asthma and COVID-19 to provide a comprehensive understanding based on the currently available published data.

Recent findings

Non-SARS human coronaviruses (HCoVs) are a significant cause of asthma exacerbations, but SARS-CoV-2 does not appear to exacerbate asthma. Data thus far strongly suggest that patients with asthma are at no increased risk of infection with SARS-CoV-2 or more severe disease if infected with COVID-19. Although the data are extremely limited on inhaled corticosteroids and biologic medications, there remain no data suggesting that these therapeutics positively or negatively impact the severity or outcome of COVID-19.

Data are rapidly evolving regarding COVID-19 and asthma. At this time, asthma does not appear to positively or negatively affect outcomes of COVID-19; however, it is imperative that practitioners keep abreast of the changing literature as we await a vaccine and control of this pandemic.
Thickness of rectus abdominis measured by ultrasound in critically ill patients after abdominal surgery
Authors: Yang Ming-Chieh , Wang Yung-Chang , Chen I-Shu , Huang Wei-Chun
Published: January 2021

BACKGROUND

Early identification of patients at high risk of prolonged mechanical ventilation is important in critical care. Sarcopenia, the loss of muscle mass and function, has been reported to be associated with extended mechanical ventilation and prolonged ICU stay. Although ultrasound is noninvasive and widely used in critical care, there is no standard method of using it to assess sarcopenia.

OBJECTIVES

The study aims to investigate the relationship between outcomes of critically ill patients and the ratio of BMI to the thickness of rectus abdominis measured by a standardised ultrasound examination.

DESIGN

A retrospective cohort study.

SETTING

Surgical ICU of a tertiary referral hospital, from October 2017 to June 2018. The thickness of rectus abdominis (RA) was measured while performing extended focused assessment sonography for trauma. BMI was divided by the thickness of rectus abdominis over the upper abdomen to derive the BMI-RA thickness ratio.

PATIENTS

Sixteen male and 11 female patients admitted to ICU after major abdominal surgery.

MAIN OUTCOME MEASURES

The primary outcome was in-hospital mortality, and the secondary outcomes were durations of mechanical ventilation, ICU stay and hospital stay. The disease severity, serum albumin level and BMI-RA thickness ratio were also analysed.

RESULTS

Ultrasound measurement was easy to perform without adverse effects. The BMI-RA thickness ratio was significantly higher in nonsurvivors and was associated with ICU stay, hospital stay and duration of mechanical ventilation. Multivariable logistic regression showed that the BMI-RA thickness ratio was a predictor of in-hospital mortality.

CONCLUSION

The BMI-RA thickness ratio is related to the outcomes of patients transferred to ICU after major abdominal surgery. Measuring the thickness of rectus abdominis by ultrasound is well tolerated and easy to perform in surgical ICU. Larger prospective studies are required to confirm current findings.
Mid-axillary transversus abdominis plane block and stress response after abdominal hysterectomy
Authors: Ismail Samina , Ahmed Aliya , Hoda Muhammad Q. , Asghar Samie , Habib Aysha , Aziz Aliya
Published: January 2021

BACKGROUND

The hormonal response to surgical trauma can have detrimental effects on patients. Transversus abdominis plane (TAP) block, which can improve analgesia after total abdominal hysterectomy (TAH) might attenuate the peri-operative stress response.

OBJECTIVE

To evaluate the ability of the TAP block to reduce stress response, opioid consumption and pain following TAH and multimodal analgesia.

DESIGN

Randomised, placebo-controlled double-blind study.

SETTING

The current study was conducted at a university hospital from July 2016 to September 2017.

PATIENTS

Fifty patients scheduled for TAH were included. Anaesthesia and postoperative analgesia were standardised.

INTERVENTION

After induction of anaesthesia, patients were allocated into two groups: ultrasound-guided bilateral mid-axillary TAP block with 20 ml of bupivacaine 0.25% (Group T) or 0.9% saline (Group C).

MAIN OUTCOME MEASURES

Levels of free serum cortisol, metanephrine and normetanephrine at 60 min and 6, 12 and 24 h after surgical incision. Pain scores and opioid consumption during the first 24 h after surgery.

RESULTS

There was no statistically significant difference between the median [IQR] peri-operative levels of stress hormones and pain scores between groups. Compared with baseline value 9.90 [4.2 to 23.1], free serum median cortisol levels were significantly high at 6 h in Group T, 23.6 [10.1 to 42.9] P = 0.015 and Group C 23.6 [9.9 to 46.3] P = 0.014. Only Group C showed significant elevation from the baseline median levels of plasma metanephrine at 60 min, 52.8 [33.4 to 193.2] P = 0.001, 6 h, 92.70 [2.4 to 202.6] P = 0.005 and normetanephrine at 60 min 83.44 [28.98 to 114.86] P = 0.004, 6 h 78.62 [36.6 to 162.31] P = 0.0005 and 24 h 80.96 [8.6 to 110.5] P = 0.025. Mean ± SD opioid consumption was similar in both groups: 39.60 ± 14.87 in Group T vs. 43.68 ± 14.93 in Group C (P = 0.338).

CONCLUSION

Mid-axillary TAP block does not improve stress response and analgesia in patients undergoing TAH receiving multimodal analgesia.

TRAIL REGISTRATION

ClinicalTrial.gov identifier: NCT03443271.
Protective effect of sevoflurane on vascular endothelial glycocalyx in patients undergoing heart valve surgery
Authors: Fang Fu-Quan , Sun Jie-Hao , Wu Qiao-Lin , Feng Lin-Ya , Fan Yu-Xiu , Ye Jun-Xin , Gao Wei , He Guo-Liang , Wang Wei-Jian
Published: January 2021

BACKGROUND

The glycocalyx plays an important physiological role and may be damaged during cardiopulmonary bypass. Sevoflurane can protect the glycocalyx; however, its relevance in a clinical setting is unknown.

OBJECTIVE

Glycocalyx degradation during cardiopulmonary bypass in patients was investigated. On the basis of the available experimental data, we hypothesised that sevoflurane-based anaesthesia would confer additional protection against cardiopulmonary bypass-induced glycocalyx damage.

DESIGN

Randomised controlled study.

SETTING

Clinical study at The First Affiliated Hospital of Wenzhou Medical University between June 2018 and March 2019.

PATIENTS

Fifty-one patients.

INTERVENTIONS

After intubation and mechanical ventilation, patients undergoing elective heart valve surgery were maintained under general anaesthesia with either propofol or sevoflurane during surgery.

MAIN OUTCOME MEASURES

Glycocalyx markers (such as syndecan-1, heparan sulphate and hyaluronan), sheddases responsible for the degradation of the endothelial glycocalyx (such as matrix metalloproteinase-9 and cathepsin-B), urine albumin-to-creatinine ratio and levels of lactic acid and myocardial enzymes were all measured. Postoperative mechanical ventilation time and length of stay in the cardiac care unit and hospital were also measured. Morbidity and mortality after 30 days and 1 year were evaluated.

RESULTS

The vascular endothelial glycocalyx was damaged during cardiopulmonary bypass. The glycocalyx damage in the sevoflurane group was less extensive than that in the propofol group. The urine albumin-to-creatinine ratio increased in both groups but was lower in the sevoflurane group. Enzymes including matrix metalloproteinase-9 and cathepsin-B were positively correlated with glycocalyx marker concentrations. After operation, the sevoflurane group showed lower levels of lactic acid and myocardial enzyme, as well as shorter duration of postoperative mechanical ventilation than the propofol group.

CONCLUSION

Sevoflurane can decrease glycocalyx degradation in patients undergoing heart valve surgery under cardiopulmonary bypass.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, chictr.org.cn, identifier: ChiCTR1800016367.
Biopsychosocial predictors of depressive symptoms in the perimenopause—findings from the Swiss Perimenopause Study
Authors: Willi Jasmine , Süss Hannah , Grub Jessica , Ehlert Ulrike
Published: January 2021

Objective:

The perimenopause is associated with increased hormone fluctuations and an elevated risk of depression. A number of predictors of depressive symptoms in the menopausal transition have previously been suggested. The purpose of this study was to investigate a set of biopsychosocial predictors of depressive symptoms in perimenopausal women.

Methods:

This cross-sectional study, investigating 114 perimenopausal women (according to the STRAW criteria) aged 40-56 years, was conducted within the scope of the Swiss Perimenopause Study. Multiple regression analyses were performed to identify the most accurate model predicting perimenopausal depressive symptoms. Depressive symptoms were assessed with the German version of the Center of Epidemiologic Studies Depression Scale (CES-D). Validated questionnaires were used to examine psychophysiological complaints, stress, self-esteem, self-compassion, body image, and social support. Estradiol (E2) and progesterone (P4) were assessed through saliva samples, and follicle-stimulating hormone and luteinizing hormone were determined through dried blood spot samples. Seven saliva samples per participant were used to investigate absolute levels and fluctuations of sex steroids. All other variables were measured once.

Results:

Multiple regression analyses revealed that E2 fluctuations (β=0.15, P = 0.015), history of depression (β=0.14, P = 0.033), menopausal symptoms (β=0.47, P < 0.0001), perceived stress (β=0.17, P = 0.014), body image (β= −0.25, P = 0.014) and self-esteem (β=−0.35, P < 0.0001) were predictive of perimenopausal depressive symptoms (R
2 = 0.60). P4 fluctuations and absolute levels of hypothalamic-pituitary-gonadal hormone were not statistically significant.

Conclusions:

E2 fluctuations were shown to be predictive of depressive symptoms in the perimenopause. Moreover, the presence of burdensome complaints and chronic stress as well as a poor self-evaluation seem to promote depressive symptoms in perimenopausal women.
Possible association of early menopause with worse physical function: a systematic review
Authors: de Souza Macêdo Pedro Rafael , Rocha Tiago Novais , Gomes Fernandes Sabrina Gabrielle , Apolinário Vieira Mariana Carmem , Jerez-Roig Javier , Aires da Câmara Saionara Maria
Published: January 2021

Importance:

Menopause at younger ages is associated with a greater risk of adverse health outcomes such as osteoporosis, chronic diseases, and death. However, the association with physical function has not been well established.

Objective:

Assess the association between timing of menopause and different measures of physical function.

Evidence Review:

Searches on the PubMed, Cochrane Library, SciELO, LILACS, and Web of Science databases were conducted. Observational studies on the association between age at menopause and measures of physical function were included, with no restriction for publication date or language. Methodological quality was assessed by the “Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies.”

Findings:

Four cross-sectional studies were included, totaling 13,846 participants. These investigated five measures of physical function: gait speed, grip strength, standing balance, chair stand, and self-reported functional limitations. Poor physical function was associated with premature (<40 y) or early menopause (<45 y) in all the studies, with significant results only for grip strength, gait speed, and functional limitation. Premature and early menopause were associated with weaker grip strength [between 2.58 kg (95% CI = 0.74 to 4.43) and 5.21 kg (2.18 to 8.25)], and lower gait speed [between 0.03 m/s (0.01 to 0.06) and 0.06 m/s (0.02 to 0.09)]. Menopause after the age of 50 is associated with less likelihood of functional limitation [OR between 0.52 (95% CI = 0.29 to 0.95) and 0.61 (0.40 to 0.95)] compared with premature and early menopause. Two measures of physical function (chair stand test and standing balance) were not significantly associated with age at menopause.

Conclusion:

Only four cross-sectional studies showed that earlier ages at menopause are associated with poor physical function (grip strength, gait speed, and self-reported functional limitations), but given the high heterogeneity of the studies, no consensus is possible. Longitudinal studies are needed to explore the association between age at menopause and different measures of physical function as well as the influence of different socioeconomic conditions between countries on functioning.
#Menopause on Instagram: a mixed-methods study
Authors: Arseneau Morgan E. , Backonja Uba , Litchman Michelle L. , Karimanfard Rojin , Sheng Xiaoming , Taylor-Swanson Lisa
Published: January 2021

Objective:

The aims of this study were to: (1) characterize the menopause transition (MT) on social media and (2) determine if concordance or discordance exists when comparing MT-focused social media posts and biomedical research literature.

Methods:

We analyzed 440 sequential Instagram posts with the hashtag #menopause over 2 weeks from January to February 2019. Posts were composed of 299 unique accounts, resulting in an average of 1.7 posts per account (standard deviation [SD] 1; range 1-9; median 1 and interquartile range [IQR] 1-2). Each account had an average of 2,616 followers (SD 11,271; range 3-129,000; median 421.5 and IQR 177-1,101). Content and thematic analyses were completed for posts, images, and videos to identify codes related to the MT. The top 15 codes were then searched along with the key term “menopause” in PubMed to ascertain the level of concordance between Instagram content and peer-reviewed literature on the MT.

Results:

We identified 69 codes in our corpus of Instagram content, resulting in 9 categories: physical health, mental health, complementary and integrative health, advertising, social, advice, self-care, nature, and self-expression (kappa 0.95-1.00). The most prevalent codes were related to weight loss/fitness (20.5%) and hormones (18.4%). The majority of frequent codes identified in Instagram posts were infrequently listed in biomedical literature related to menopause. However, there were two codes, Weight loss/Fitness and Hot flashes, that were frequently discussed in Instagram posts and the biomedical literature.

Conclusions:

The examination of #menopause on Instagram provides novel insights for researchers and clinicians. Our findings provide a better understanding of the experiences and support needs of individuals experiencing menopause. Furthermore, codes related to menopause have low prominence in the biomedical literature, suggesting key topics that could be explored in the future.

Video Summary:

http://links.lww.com/MENO/A695.
Information system use antecedents of nursing employee turnover in a hospital setting
Authors: Thompson Samuel C. , Holmgren A. Jay , Ford Eric W.
Published: January 2021

Background

Voluntary turnover (VTO) of nursing employees is expensive for hospital systems and is often associated with lower levels of patient satisfaction, as well as adverse patient outcomes such as falls and medication errors.

Purpose

The aim of this study was to establish nurses’ electronic medical record (EMR) use patterns and test if they can be used to predict VTO.

Methodology/Approach

The study followed 1,836 hospital nurses via the collection of EMR metadata through two 1-month time periods that were 1 year apart. Machine learning algorithms were then used to derive patterns of EMR utilization using VTO as a key variable for classification. Post hoc analysis of the most predictive variables was conducted.

Results

The predictive model was effective in identifying which nurses would turnover 73.4% of the time and which nurses would not turnover 84.1% of the time.

Practice Applications

The ability to accurately predict nurses’ intentions to leave is critical to reducing turnover. Early identification can lead to specific interventions to mitigate factors that are adversely impacting the nursing experience. Post hoc analysis and the key informant interviews indicated that many nurses do not appear to have good EMR navigation skills and spend significant effort in search of patient information.
Workplace Mental Health
Authors: Fragala Maren S. , Hunter Jennifer L. , Satish Anita , Jelovic Nicole A. , Carr Susan , Bailey Allison M. , Stokes Meghan , Hayward Joanna I. , Kim Paul M. , Peters Matthew E.
Published: January 2021

Objective:

To evaluate a proactive, voluntary screening program designed to identify employees with emerging mental health risk and engage them in care.

Methods:

Risk was proactively identified through online screening of 344 participants. At-risk participants were offered a mental health care concierge to provide support, develop a care plan, and connect to care.

Results:

Risk for common mental health conditions was identified in 244 (71%) participants, of whom 66 (27%) connected with a care concierge. Compared with participants who did not connect to a care concierge, those who did were more likely to report a financial crisis (68.2% vs 50.8%) and less likely to report verbal abuse (9.1% vs 19.6%) and difficulty meeting daily needs (12.1% vs 25.1%).

Conclusion:

Implementation of this screening program identified employees at risk for mental health conditions and facilitated connection to care.
Evidence and clinical trials in Endourology: where are we going
Authors: Donaldson James Fergus , McClinton Samuel
Published: January 2021

Purpose of review

There is an ongoing explosion in the amount and quality, of research in the field of Endourology. From a solid basis of systematic reviews and small, single centre trials it has been possible to design large randomised controlled trials in the UK and in the USA. This review will describe some of the more recent trials (small and large) that are helping to provide a solid evidence base for our practice in Endourology.

On-going studies

Randomised controlled trial (RCTs) include: The Therapeutic Interventions for Stones in the Ureter (TISU), the Percutaneous nephrolithotomy, flexible Ureterorenoscopy and extracorporeal Shockwave lithotripsy for lower pole kidney stones (PURE RCTs) and the Prevention of Urinary Stones with Hydration (PUSH). Quality of life (QoL) measures and studies include: the Wisconsin Stone QoL Questionnaire, the Cambridge Renal Stone PROM, the Cambridge Ureteral Stone PROM, the Urinary stone and Intervention QoL questionnaire and the Study to Enhance Understanding of sTent-associated Symptoms (STENTS). The Core Outcome Set in Trials on treatments for Renal and UreteriC sTones (COSTRUCT) study aims to define a core outcome set to be used in future trials.

On-going studies will provide higher quality evidence on the treatment of ureteric and renal stones to inform treatment decision making and guideline recommendations. They will also guide decisions relating to prevention and recurrence and give insight into the true impact of urinary stones and endourological interventions on patients’ quality of life. Future studies will incorporate big data and artificial intelligence.