A balancing act: sex selection after pre-implantation genetic testing for aneuploidy for first versus second baby.

STUDY QUESTION: How often do patients undergoing frozen embryo transfer (FET) after preimplantation genetic testing for aneuploidy (PGT-A) choose to select for sex and do sex selection rates differ before and after successful delivery of a first baby? SUMMARY ANSWER: When a choice was available between male and female embryos, patients selected the sex more frequently when trying to conceive the second child (62%) as compared to the first child (32.4%) and most commonly selected for the opposite sex of the first child. WHAT IS KNOWN ALREADY: Sex selection is widely available in US fertility clinics. However, the rate of sex selection for patients undergoing FET after PGT-A is unknown. STUDY DESIGN, SIZE, DURATION: This is a retrospective cohort study of 585 patients that took place between January 2013 and February 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study took place at a single, urban academic fertility center in the USA. Patients were included if they had a live birth after single euploid FET and returned for at least one subsequent euploid FET. The primary outcomes were the rates of sex selection for first versus second baby. Secondary outcomes were rate of selection for same versus opposite sex as first live birth and overall rate of selection for males versus females. MAIN RESULTS AND THE ROLE OF CHANCE: Five hundred and eighty-five patients underwent a total of 1560 single euploid FETs resulting in either one or two live births. A choice between male and female euploid embryos was available for 919 FETs (first child: 67.5% (519/769) versus second child: 50.6% (400/791), P < 0.01). When a choice was available, patients selected the sex more frequently when trying to conceive the second child (first child: 32.4% (168/519) versus second child: 62.0% (248/400), P < 0.01). When sex was selected after first live birth, the opposite sex of the first child was selected 81.8% (203/248 FETs) of the time. Of transfers that involved sex selection, rates of male and female selection were similar for the first child, but selection for females was greater for the second child (first child: 51.2% (86/168) male versus 48.9% (82/168) female, second child: 41.1% (102/248) male versus 58.9% (146/248) female, P < 0.04). LIMITATIONS, REASONS FOR CAUTION: The study was performed at one urban academic medical center in the Northeastern US, which may limit generalizability to other settings where PGT-A may be performed less frequently, or sex selection may be limited or not permitted. In addition, we could not reliably account for whether patients or their partners had prior children and if so, of what sex. WIDER IMPLICATIONS OF THE FINDINGS: Patients undergoing PGT-A with both male and female euploid embryos were more likely to select for sex when attempting a second child and usually selected for the opposite sex of their first child. These findings highlight the potential for family balancing for patients who undergo PGT-A in settings where sex selection is permitted. STUDY FUNDING/COMPETING INTEREST(S): This study received no funding. The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Temporal Dynamics of Botrytis cinerea and Sclerotinia sclerotiorum in Seed Alfalfa Fields of Southern Alberta, Canada.

Blossom blight of seed alfalfa (Medicago sativa L.), caused by the fungal pathogens Botrytis cinerea and Sclerotinia sclerotiorum, is a potentially devastating disease on the Canadian Prairies in moist growing seasons. Monitoring the airborne spore concentrations of these pathogens could facilitate disease forecasting in the region. Nineteen seed alfalfa fields in southern Alberta, Canada were assessed throughout the growing seasons of 2014 and 2015. Trace levels of blossom blight symptoms were found in both years; however, plated floret and pod samples indicated that, overall, B. cinerea increased over the growing season whereas S. sclerotiorum decreased. In both seasons, Burkard 7-day volumetric spore samplers collected daily aerosol samples, and weather stations recorded environmental variables in three fields. Conidia and ascospores collected were quantified each day with a real-time polymerase chain reaction assay. Spore quantification indicated that both B. cinerea and S. sclerotiorum numbers remained low in July and increased in August. Both species had multiple days with high spore discharge, with seasonal maxima of 21,137 conidia and 2,265 ascospores. Exploratory model development indicated that spore discharge of both fungi is associated with environmental stressors such as large changes in relative humidity or high temperatures on preceding days.

A multiplex PCR assay for the detection and quantification of Sclerotinia sclerotiorum and Botrytis cinerea.

UNLABELLED: Traditional culture methods for identifying the plant fungal pathogens Sclerotinia sclerotiorum (Lib.) de Bary and Botrytis cinerea Pers.:Fr. are slow and laborious. The goal of this study was to develop a multiplex real-time PCR (qPCR) assay to detect and quantify DNA from S. sclerotiorum and B. cinerea. A primer set (SsIGS_5) for S. sclerotiorum was designed that targeted the intergenic spacer (IGS) regions of the ribosomal DNA. Addition of a probe to the assay increased its specificity: when the primer/probe set was tested against 21 fungal species (35 strains), amplification was detected from all S. sclerotiorum strains and no other species. For qPCR, the SsIGS_5 primer and probe set exhibited a linear range from 7·0 ng to 0·07 pg target DNA (R(2)  = 0·99). SsIGS_5 was then multiplexed with a previously published primer/probe set for B. cinerea to develop a high-throughput method for the detection and quantification of DNA from both pathogens. When multiplexed, the sensitivity and specificity of both assays were not different from individual qPCR reactions. The multiplex assay is currently being used to detect and quantify S. sclerotiorum and B. cinerea DNA from aerosol samples collected in commercial seed alfalfa fields. SIGNIFICANCE AND IMPACT OF THE STUDY: A primer and probe set for the quantification of Sclerotinia sclerotiorum DNA in a PCR assay was developed. The probe-based nature of this assay signifies an improvement over previous assays for this species by allowing multiplex reactions while maintaining high sensitivity. The primer/probe set was used in a multiplex real-time PCR assay for the quantification of S. sclerotiorum and Botrytis cinerea DNA, enabling rapid analysis of environmental samples. In crops susceptible to both pathogens, this multiplex assay can be used to quickly quantify the presence of each pathogen.

[Preclinical evaluation of coated knee implants for allergic patients]. / Präklinische Ergebnisse beschichteter Knieimplantate für Allergiker.

BACKGROUND: 10-15% of the population show allergic reactions against skin contact to metals as nickel, cobalt or chromium and have thus a risk of not tolerating implants containing those materials. The relationship between periimplantary hypersensivity reaction and given cutaneous contact allergy is currently unknown. A new developed multilayer coating system is supposed to prevent long-term allergic reactions that may result from uncoated implants. METHODS: Stability and function (concerning bonding durability, wear and ion release to the serum) of the multilayer coating system has been examined in a test series. RESULTS: The specific architecture of the multilayer coating system evidences a very good bonding durability. The results of the test in the simulator show a reduction of wear of approximately 60% compared to the uncoated implants. Ion concentrations within the serum of the wear tests were by magnitudes lower than those measured in reference tests on uncoated components. CONCLUSION: The results of the preclinical evaluation prove that the durability and function of the multilayer coating system are as intended.

A critical appraisal of overdiagnosis: estimates of its magnitude and implications for lung cancer screening.

BACKGROUND: The magnitude of overdiagnosis is a critical and unresolved issue in lung cancer (LC) screening:(1) its contribution to the increase in survival constitutes specious evidence of benefit;(2) overdiagnosed individuals who undergo resection will experience a reduction in life expectancy, partially or completely offsetting the benefit received by others in whom earlier intervention proves curative. METHOD: Critical analysis of studies in opposition and support of the view that LC screening imposes a substantial burden of overdiagnosis. RESULTS: Approximately 25%, possibly more, of radiographically (chest x ray) diagnosed LC appears to be overdiagnosed. Based on the observed tumour volume doubling time of low dose CT identified small malignant pulmonary nodules, CT will markedly augment lead time, increasing exposure to competing lethal morbidities, thereby increasing overdiagnosis. CONCLUSION: To reduce all-cause mortality, CT screening will need to reduce LC mortality by an amount that exceeds the increase in mortality attributable to surgery and loss of pulmonary reserve in persons who are overdiagnosed or pathologically understaged (ie, with occult micrometastases). Presently, there is no evidence that CT screening will achieve any reduction in LC mortality.

Biological interactions mediate context and species-specific sensitivities to salinity.

Toxicants have both sub-lethal and lethal effects on aquatic biota, influencing organism fitness and community composition. However, toxicant effects within ecosystems may be altered by interactions with abiotic and biotic ecosystem components, including biological interactions. Collectively, this generates the potential for toxicant sensitivity to be highly context dependent, with significantly different outcomes in ecosystems than laboratory toxicity tests predict. We experimentally manipulated stream macroinvertebrate communities in 32 mesocosms to examine how communities from a low-salinity site were influenced by interactions with those from a high-salinity site along a gradient of salinity. Relative to those from the low-salinity site, organisms from the high-salinity site were expected to have greater tolerance and fitness at higher salinities. This created the potential for both salinity and tolerant-sensitive organism interactions to influence communities. We found that community composition was influenced by both direct toxicity and tolerant-sensitive organism interactions. Taxon and context-dependent responses included: (i) direct toxicity effects, irrespective of biotic interactions; (ii) effects that were owing to the addition of tolerant taxa, irrespective of salinity; (iii) toxicity dependent on sensitive-tolerant taxa interactions; and (iv) toxic effects that were increased by interactions. Our results reinforce that ecological processes require consideration when examining toxicant effects within ecosystems.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'.

A comparison of the incidence of undiagnosed congenital heart disease in hospital born and home born children.

OBJECTIVE: To evaluate the incidence of otherwise undiagnosed congenital heart disease (CHD) in a population of children born in a hospital with routine pulse oximetry (RPO) screening compared to children born at home. METHODS: We reviewed 15 years of births at 2 hospitals for incidence of undiagnosed CHD with RPO. The Health Department reviewed the same data for out of hospital births. RESULTS: A total of 50,545 hospital births were screened and 1,274 children were born outside the hospital. There were 28 hospital-born babies diagnosed with cyanotic CHD prior to nursery discharge. Only one of these babies would not have been diagnosed without RPO. Three children were missed and there were 3 false positives. Sensitivity and positive predictive value of RPO was 25%, specificity and negative predictive value of RPO exceed 99%. The incidence of CHD requiring RPO diagnosis was roughly one birth per 50,000. Two children born at home with undiagnosed CHD were missed. One of these children presented with neonatal demise. CONCLUSION: RPO screening is still valuable in diagnosing CHD only diagnosable with RPO. However, the incidence of CHD requiring RPO to diagnose is similar to other congenital diseases which are not mandated national screening tests. In our limited experience a patient is roughly 25 times more likely to have undiagnosed CHD if they are born outside of a hospital.

Control of and synthesis in Lactobacillus acidophilus Role of RNA and free amino acids.

In Lactobacillus acidophilus, the DNA synthesis in cells incubated in the absence of essential amino acids reaches levels corresponding to the initiation of further replication cycles than just to completing the cycles already running. This "relaxation of DNA synthesis" is stimulated by the presence of inhibitors of protein synthesis and by the presence of deoxyadenylate. These enhancements of DNA replication are cancelled by actinomycin D. In the presence of inhibitors of protein synthesis, the relaxtion of DNA synthesis is further stimulated by free amino acids. The effect of free amino acids, unlike in the former cases, is not inhibited by actinomycin D. It proposed that the chromosome replication in Lactobacillus acidophilus is regulated similarly as in some plasmids, i.e. independently of the synthesis of protein, depending on the synthesis of RNA and, in addition, on the presence of free amino acids.

Nucleotide composition bias and CpG dinucleotide content in the genomes of HIV and HTLV 1/2.

Nucleotide compositions of the HIV subfamily and HTLV 1/2 genomes are strongly biased in a remarkably opposite way; HIV is adenine-rich and cytosine-poor while HTLV 1/2 is cytosine-rich and adenine-poor. In addition, the CpG dinucleotides are underrepresented in HIV but abundant in HTLV 1/2. By these two properties the genomes of HIV and HTLV 1/2 mimic an (A + T)-rich and (G + C)-rich segment of the host genome, respectively. These dramatic differences between the two human retroviruses might have evolved to direct integration of the retroviral genomes into specific segments of the human chromosomes.

Merging extracellular domains: fold prediction for laminin G-like and amino-terminal thrombospondin-like modules based on homology to pentraxins.

Using a new method for construction and database searches of sequence consensus strings, we have identified a new superfamily of protein modules comprising laminin G, thrombospondin N and the pentraxin families. The conserved patterns correspond mainly to hydrophobic core residues located in central beta strands of the known three-dimensional structures of two pentraxins, the human C-reactive protein and the serum amyloid P-component. Thus, we predict a similar jellyroll fold for all members of this superfamily. In addition, the conservation of two exposed aspartate residues in the majority of superfamily members suggests hitherto unrecognised functional sites.

Architecture of research in psychiatry, 1953 to 1983.

Although there has been one report on the trends in study design in general medicine, we are aware of none for general psychiatry prior to this communication. Accordingly, articles from the American Journal of Psychiatry (N = 194) and the Archives (N = 109) were randomly sampled for the years 1953, 1963, 1973, and 1983. Two raters achieved reliability (kappa = .82) for recognizing the major types of study design (cohort, clinical trial, case control, cross sectional, case report, and review). There was a significant change in study architecture over time, with the percentage of review articles declining and the percentage of case-control and cross-sectional studies increasing. Another major finding was a large increase in use of inclusion and exclusion criteria for diagnosis in non-review article studies. The general trends are for increasingly sophisticated research designs to be used in psychiatry research. The quality of research designs in psychiatry for 1983 also compares favorably with research designs found in a respected medicine journal.

Outcome of panic disorder. Relationship to diagnostic subtypes and comorbidity.

Eighty-nine subjects with panic disorder, who had been naturalistically treated, and 46 nonanxious controls were followed up after 3 years. Although they remained symptomatic, most subjects with panic disorder reported relatively little distress or social maladjustment. The course of panic disorder was characterized by fluctuating anxiety and depressive symptoms. Panic subtypes (uncomplicated, limited phobic avoidance, and extensive phobic avoidance) and Axis I and II comorbidity (major depression and personality disorders) were highly predictive of symptoms and social adjustment after 3 years. Abnormal personality was, in fact, the strongest predictor of social maladjustment in both subjects with panic disorder and controls. The results showed that while panic disorder has a favorable outcome, the illness is a chronic one that may require continuing treatment. They also show that subtypes and comorbid disturbances are important predictors of outcome.

A pathway model of lipid metabolism to predict the effect of genetic variability on lipid levels.

Complex phenotypes such as serum lipid concentrations involve numerous genes and require the analysis of the combined effects of these gene products. We modeled the interactions of six key lipid metabolism genes by means of differential equations. We tested the model by inserting the effects of known mutations in the low-density lipoprotein receptor gene and the lipoprotein lipase gene, as well as the effects of a high-fat diet, and observed that the predictions corresponded very well to published measurements. Models such as the one that we present here will become indispensable for analyzing and understanding the effects of variation in multiple genes.

Prediction of nonsynonymous single nucleotide polymorphisms in human disease-associated genes.

Analysis of human genetic variation can shed light on the problem of the genetic basis of complex disorders. Nonsynonymous single nucleotide polymorphisms (SNPs), which affect the amino acid sequence of proteins, are believed to be the most frequent type of variation associated with the respective disease phenotype. Complete enumeration of nonsynonymous SNPs in the candidate genes will enable further association studies on panels of affected and unaffected individuals. Experimental detection of SNPs requires implementation of expensive technologies and is still far from being routine. Alternatively, SNPs can be identified by computational analysis of a publicly available expressed sequence tag (EST) database following experimental verification. We performed in silico analysis of amino acid variation for 471 of proteins with a documented history of experimental variation studies and with confirmed association with human diseases. This allowed us to evaluate the level of completeness of the current knowledge of nonsynonymous SNPs in well studied, medically relevant genes and to estimate the proportion of new variants which can be added with the help of computer-aided mining in EST databases. Our results suggest that approx. 50% of frequent nonsynonymous variants are already stored in public databases. Computational methods based on the scan of an EST database can add significantly to the current knowledge, but they are greatly limited by the size of EST databases and the nonuniform coverage of genes by ESTs. Nevertheless, a considerable number of new candidate nonsynonymous SNPs in genes of medical interest were found by EST screening procedure.

Self-organizing hierarchic networks for pattern recognition in protein sequence.

We present a method based on hierarchical self-organizing maps (SOMs) for recognizing patterns in protein sequences. The method is fully automatic, does not require prealigned sequences, is insensitive to redundancy in the training set, and works surprisingly well even with small learning sets. Because it uses unsupervised neural networks, it is able to extract patterns that are not present in all of the unaligned sequences of the learning set. The identification of these patterns in sequence databases is sensitive and efficient. The procedure comprises three main training stages. In the first stage, one SOM is trained to extract common features from the set of unaligned learning sequences. A feature is a number of ungapped sequence segments (usually 4-16 residues long) that are similar to segments in most of the sequences of the learning set according to an initial similarity matrix. In the second training stage, the recognition of each individual feature is refined by selecting an optimal weighting matrix out of a variety of existing amino acid similarity matrices. In a third stage of the SOM procedure, the position of the features in the individual sequences is learned. This allows for variants with feature repeats and feature shuffling. The procedure has been successfully applied to a number of notoriously difficult cases with distinct recognition problems: helix-turn-helix motifs in DNA-binding proteins, the CUB domain of developmentally regulated proteins, and the superfamily of ribokinases. A comparison with the established database search procedure PROFILE (and with several others) led to the conclusion that the new automatic method performs satisfactorily.

The prognostic significance of HPA-axis disturbance in panic disorder: a three-year follow-up.

Seventy-seven patients with DSM-III panic disorder underwent a baseline dexamethasone suppression test (DST), participated in an 8-week controlled treatment trial, and provided follow-up interviews 2-4 years later. The 20 patients who had exhibited DST nonsuppression at baseline had more symptoms of anxiety, more work and social disability, and a greater likelihood of ongoing major depression than did patients who had had normal DST results. DST nonsuppression in panic disorder apparently indicates a more persistent and chronically disabling condition.

Tocainide kinetics in congestive heart failure.

Our subjects were 20 patients with life-threatening or symptomatic ventricular arrhythmias refractory to standard oral antiarrhythmic drugs but responsive to intravenous lidocaine. After evaluation of arrhythmias and treatment with intravenous lidocaine, oral tocainide dosage regimens were based on age, weight, and clinical status. During initial tocainide treatment, six plasma tocainide concentrations were recorded within a single dosing interval in 17 of 20 patients, by which standard kinetic parameters were calculated. Eventual trough steady-state tocainide plasma concentrations were predicted from the derived patient-specific kinetic parameters. Mean daily tocainide dose was 1800 mg (1200 to 2400). Mean daily tocainide doses (milligram per kilogram) did not differ significantly among responders and nonresponders or among patients with or without congestive heart failure. Mean peak and trough plasma concentrations 48 hr after initiation of therapy were 9.8 and 7.5 mcg/ml. Tocainide plasma concentrations did not correlate with responders and nonresponders or identify patients who were developing adverse reactions to tocainide. There were no significant differences in any of the calculated kinetic parameters as a function of response to tocainide or the presence of congestive heart failure, but there was a trend toward smaller volumes of distribution and higher average plasma concentrations at steady state in patients with congestive heart failure. There were no significant kinetic differences among patients with and without congestive heart failure, but a trend toward higher plasma concentrations in patients with congestive heart failure and the small number of patients suggests that further data collection is necessary before dosage recommendations can be made.

Unusual occurrence of EcoP1 and EcoP15 recognition sites and counterselection of type II methylation and restriction sequences in bacteriophage T7 DNA.

Selected and counterselected oligodeoxynucleotide sequences were identified in the total sequence of bacteriophage T7 DNA using a statistical criterion derived for a probability model of the Markov chain type. All extremely rare tetra- and pentadeoxynucleotides are (or contain) recognition sequences for the Escherichia coli DNA methylases dam or dcm. Most of the 37 hexadeoxynucleotides absent from T7 DNA are recognition sequences for type II modification/restriction enzymes of E. coli or related species. In contrast to most restriction sites counterselected during evolution, the EcoP1 site GGTCT occurs 126 times in the T7 genome, and phage T7 replication is severely repressed in P1-lysogenic host cells. We demonstrate that the frequency of the EcoP1 site is determined by that of the overlapping recognition sites for T7 primase, an essential phage enzyme. The recognition site of a type III enzyme, EcoP15, is also not counterselected. In T7 DNA all 36 EcoP15 sites are arranged in such a manner that the sequence CAGCAG is confined to the H strand, the complementary sequence CTGCTG to the L strand. This "strand bias" is highly significant and, therefore, very probably selected. A functional relation between this strand bias and the refractive behaviour of phage T7 to EcoP15 restriction is suspected.