Gametocidal genes: from a discovery to the application in wheat breeding

Some species of the genus Aegilops, a wild relative of wheat, carry chromosomes that after introducing to wheat exhibit preferential transmission to progeny. Their selective retention is a result of the abortion of gametes lacking them due to induced chromosomal aberrations. These chromosomes are termed Gametocidal (Gc) and, based on their effects, they are categorized into three types: mild, intense or severe, and very strong. Gc elements within the same homoeologous chromosome groups of Aegilops (II, III, or IV) demonstrate similar Gc action. This review explores the intriguing dynamics of Gc chromosomes and encompasses comprehensive insights into their source species, behavioral aspects, mode of action, interactions, suppressions, and practical applications of the Gc system in wheat breeding. By delving into these areas, this work aims to contribute to the development of novel plant genetic resources for wheat breeding. The insights provided herein shed light on the utilization of Gc chromosomes to produce chromosomal rearrangements in wheat and its wild relatives, thereby facilitating the generation of chromosome deletions, translocations, and telosomic lines. The Gc approach has significantly advanced various aspects of wheat genetics, including the introgression of novel genes and alleles, molecular markers and gene mapping, and the exploration of homoeologous relationships within Triticeae species. The mystery lies in why gametes possessing Gc genes maintain their normality while those lacking Gc genes suffer abnormalities, highlighting an unresolved research gap necessitating deeper investigation.

A chromosome arm from Thinopyrum intermedium × Thinopyrum ponticum hybrid confers increased tillering and yield potential in wheat

Tiller number is a key component of wheat plant architecture having a direct impact on grain yield. Because of their viability, biotic resistance, and abiotic stress tolerance, wild relative species are a valuable gene source for increasing wheat genetic diversity, including yield potential. Agropyron glael, a perennial hybrid of Thinopyrum intermedium and Th. ponticum, was created in the 1930s. Recent genome analyses identified five evolutionarily distinct subgenomes (J, Jst, Jvs, Jr, and St), making A. glael an important gene source for transferring useful agronomical traits into wheat. During a bread wheat × A. glael crossing program, a genetically stable translocation line, WT153397, was developed. Sequential in situ hybridizations (McGISH) with J-, St-, and D-genomic DNA probes and pSc119.2, Afa family, pTa71, and (GAA)7 DNA repeats, as well as molecular markers specific for the wheat 6D chromosome, revealed the presence of a 6DS.6Jvs Robertsonian translocation in the genetic line. Field trials in low-input and high-input breeding nurseries over four growing seasons demonstrated the Agropyron chromosome arm's high compensating ability for the missing 6DL, as spike morphology and fertility of WT153397 did not differ significantly from those of wheat parents, Mv9kr1 and 'Mv Karizma.' Moreover, the introgressed 6Jvs chromosome arm significantly increased the number of productive tillers, resulting in a significantly higher grain yield potential compared to the parental wheat cultivars. The translocated chromosome could be highly purified by flow cytometric sorting due to the intense fluorescent labeling of (GAA)7 clusters on the Thinopyrum chromosome arm, providing an opportunity to use chromosome genomics to identify Agropyron gene variant(s) responsible for the tillering capacity. The translocation line WT153397 is an important genetic stock for functional genetic studies of tiller formation and useful breeding material for increasing wheat yield potential. The study also discusses the use of the translocation line in wheat breeding.

Supplementary information

The online version contains supplementary material available at 10.1007/s11032-024-01439-y.

Wheat Pm55 alleles exhibit distinct interactions with an inhibitor to cause different powdery mildew resistance

Powdery mildew poses a significant threat to wheat crops worldwide, emphasizing the need for durable disease control strategies. The wheat-Dasypyrum villosum T5AL·5 V#4 S and T5DL·5 V#4 S translocation lines carrying powdery mildew resistant gene Pm55 shows developmental-stage and tissue-specific resistance, whereas T5DL·5 V#5 S line carrying Pm5V confers resistance at all stages. Here, we clone Pm55 and Pm5V, and reveal that they are allelic and renamed as Pm55a and Pm55b, respectively. The two Pm55 alleles encode coiled-coil, nucleotide-binding site-leucine-rich repeat (CNL) proteins, conferring broad-spectrum resistance to powdery mildew. However, they interact differently with a linked inhibitor gene, SuPm55 to cause different resistance to wheat powdery mildew. Notably, Pm55 and SuPm55 encode unrelated CNL proteins, and the inactivation of SuPm55 significantly reduces plant fitness. Combining SuPm55/Pm55a and Pm55b in wheat does not result in allele suppression or yield penalty. Our results provide not only insights into the suppression of resistance in wheat, but also a strategy for breeding durable resistance.

Chromosome genomics facilitates the marker development and selection of wheat-Aegilops biuncialis addition, substitution and translocation lines

The annual goatgrass, Aegilops biuncialis is a rich source of genes with considerable agronomic value. This genetic potential can be exploited for wheat improvement through interspecific hybridization to increase stress resistance, grain quality and adaptability. However, the low throughput of cytogenetic selection hampers the development of alien introgressions. Using the sequence of flow-sorted chromosomes of diploid progenitors, the present study enabled the development of chromosome-specific markers. In total, 482 PCR markers were validated on wheat (Mv9kr1) and Ae. biuncialis (MvGB642) crossing partners, and 126 on wheat-Aegilops additions. Thirty-two markers specific for U- or M-chromosomes were used in combination with GISH and FISH for the screening of 44 Mv9kr1 × Ae. biuncialis BC3F3 genotypes. The predominance of chromosomes 4M and 5M, as well as the presence of chromosomal aberrations, may indicate that these chromosomes have a gametocidal effect. A new wheat-Ae. biuncialis disomic 4U addition, 4M(4D) and 5M(5D) substitutions, as well as several introgression lines were selected. Spike morphology and fertility indicated that the Aegilops 4M or 5M compensated well for the loss of 4D and 5D, respectively. The new cytogenetic stocks represent valuable genetic resources for the introgression of key genes alleles into wheat.

SMC5/6 complex-mediated SUMOylation stimulates DNA-protein cross-link repair in Arabidopsis

DNA-protein cross-links (DPCs) are highly toxic DNA lesions consisting of proteins covalently attached to chromosomal DNA. Unrepaired DPCs physically block DNA replication and transcription. Three DPC repair pathways have been identified in Arabidopsis (Arabidopsis thaliana) to date: the endonucleolytic cleavage of DNA by the structure-specific endonuclease MUS81; proteolytic degradation of the crosslinked protein by the metalloprotease WSS1A; and cleavage of the cross-link phosphodiester bonds by the tyrosyl phosphodiesterases TDP1 and TDP2. Here we describe the evolutionary conserved STRUCTURAL MAINTENANCE OF CHROMOSOMEs SMC5/6 complex as a crucial component involved in DPC repair. We identified multiple alleles of the SMC5/6 complex core subunit gene SMC6B via a forward-directed genetic screen designed to identify the factors involved in the repair of DPCs induced by the cytidine analog zebularine. We monitored plant growth and cell death in response to DPC-inducing chemicals, which revealed that the SMC5/6 complex is essential for the repair of several types of DPCs. Genetic interaction and sensitivity assays showed that the SMC5/6 complex works in parallel to the endonucleolytic and proteolytic pathways. The repair of zebularine-induced DPCs was associated with SMC5/6-dependent SUMOylation of the damage sites. Thus, we present the SMC5/6 complex as an important factor in plant DPC repair.

Non-Rabl chromosome organization in endoreduplicated nuclei of barley embryo and endosperm tissues

Rabl organization is a type of interphase chromosome arrangement with centromeres and telomeres clustering at opposite nuclear poles. Here, we analyzed nuclear morphology and chromosome organization in cycling and endoreduplicated nuclei isolated from embryo and endosperm tissues of developing barley seeds. We show that endoreduplicated nuclei have an irregular shape, less sister chromatid cohesion at 5S rDNA loci, and a reduced amount of centromeric histone CENH3. While the chromosomes of the embryo and endosperm nuclei are initially organized in Rabl configuration, the centromeres and telomeres are intermingled within the nuclear space in the endoreduplicated nuclei with an increasing endoreduplication level. Such a loss of chromosome organization suggests that Rabl configuration is introduced and further reinforced by mitotic divisions in barley cell nuclei in a tissue- and seed age-dependent manner.

Flow Cytometric Analysis and Sorting of Plant Chromosomes

Flow cytometry offers a unique way of analyzing and manipulating plant chromosomes. During a rapid movement in a liquid stream, large populations can be classified in a short time according to their fluorescence and light scatter properties. Chromosomes whose optical properties differ from other chromosomes in a karyotype can be purified by flow sorting and used in a range of applications in cytogenetics, molecular biology, genomics, and proteomics. As the samples for flow cytometry must be liquid suspensions of single particles, intact chromosomes must be released from mitotic cells. This protocol describes a procedure for preparation of suspensions of mitotic metaphase chromosomes from meristem root tips and their flow cytometric analysis and sorting for various downstream applications.

Flow karyotyping of wheat-Aegilops additions facilitate dissecting the genomes of Ae. biuncialis and Ae. geniculata into individual chromosomes

Breeding of wheat adapted to new climatic conditions and resistant to diseases and pests is hindered by a limited gene pool due to domestication and thousands of years of human selection. Annual goatgrasses (Aegilops spp.) with M and U genomes are potential sources of the missing genes and alleles. Development of alien introgression lines of wheat may be facilitated by the knowledge of DNA sequences of Aegilops chromosomes. As the Aegilops genomes are complex, sequencing relevant Aegilops chromosomes purified by flow cytometric sorting offers an attractive route forward. The present study extends the potential of chromosome genomics to allotetraploid Ae. biuncialis and Ae. geniculata by dissecting their M and U genomes into individual chromosomes. Hybridization of FITC-conjugated GAA oligonucleotide probe to chromosomes suspensions of the two species allowed the application of bivariate flow karyotyping and sorting some individual chromosomes. Bivariate flow karyotype FITC vs. DAPI of Ae. biuncialis consisted of nine chromosome-populations, but their chromosome content determined by microscopic analysis of flow sorted chromosomes indicated that only 7M^b and 1U^b could be sorted at high purity. In the case of Ae. geniculata, fourteen chromosome-populations were discriminated, allowing the separation of nine individual chromosomes (1M^g, 3M^g, 5M^g, 6M^g, 7M^g, 1U^g, 3U^g, 6U^g, and 7U^g) out of the 14. To sort the remaining chromosomes, a partial set of wheat-Ae. biuncialis and a whole set of wheat-Ae. geniculata chromosome addition lines were also flow karyotyped, revealing clear separation of the GAA-rich Aegilops chromosomes from the GAA-poor A- and D-genome chromosomes of wheat. All of the alien chromosomes represented by individual addition lines could be isolated at purities ranging from 74.5% to 96.6% and from 87.8% to 97.7%, respectively. Differences in flow karyotypes between Ae. biuncialis and Ae. geniculata were analyzed and discussed. Chromosome-specific genomic resources will facilitate gene cloning and the development of molecular tools to support alien introgression breeding of wheat.

Transfer of the ph1b Deletion Chromosome 5B From Chinese Spring Wheat Into a Winter Wheat Line and Induction of Chromosome Rearrangements in Wheat-Aegilops biuncialis Hybrids

Effective utilization of genetic diversity in wild relatives to improve wheat requires recombination between wheat and alien chromosomes. However, this is suppressed by the Pairing homoeologous gene, Ph1, on the long arm of wheat chromosome 5B. A deletion mutant of the Ph1 locus (ph1b) has been used widely to induce homoeologous recombination in wheat × alien hybrids. However, the original ph1b mutation, developed in Chinese Spring (CS) background has poor agronomic performance. Hence, alien introgression lines are first backcrossed with adapted wheat genotypes and after this step, alien chromosome segments are introduced into breeding lines. In this work, the ph1b mutation was transferred from two CSph1b mutants into winter wheat line Mv9kr1. Homozygous genotypes Mv9kr1 ph1b/ph1b exhibited improved plant and spike morphology compared to Chinese Spring. Flow cytometric chromosome analysis confirmed reduced DNA content of the mutant 5B chromosome in both wheat genotype relative to the wild type chromosome. The ph1b mutation in the Mv9kr1 genotype allowed wheat-alien chromosome pairing in meiosis of Mv9kr1ph1b_K × Aegilops biuncialis F₁ hybrids, predominantly with the M^b-genome chromosomes of Aegilops relative to those of the U^b genome. High frequency of wheat-Aegilops chromosome interactions resulted in rearranged chromosomes identified in the new Mv9kr1ph1b × Ae. Biuncialis amphiploids, making these lines valuable sources for alien introgressions. The new Mv9kr1ph1b mutant genotype is a unique resource to support alien introgression breeding of hexaploid wheat.

Draft Sequencing Crested Wheatgrass Chromosomes Identified Evolutionary Structural Changes and Genes and Facilitated the Development of SSR Markers

Crested wheatgrass (Agropyron cristatum), a wild relative of wheat, is an attractive source of genes and alleles for their improvement. Its wider use is hampered by limited knowledge of its complex genome. In this work, individual chromosomes were purified by flow sorting, and DNA shotgun sequencing was performed. The annotation of chromosome-specific sequences characterized the DNA-repeat content and led to the identification of genic sequences. Among them, genic sequences homologous to genes conferring plant disease resistance and involved in plant tolerance to biotic and abiotic stress were identified. Genes belonging to the important groups for breeders involved in different functional categories were found. The analysis of the DNA-repeat content identified a new LTR element, Agrocen, which is enriched in centromeric regions. The colocalization of the element with the centromeric histone H3 variant CENH3 suggested its functional role in the grass centromere. Finally, 159 polymorphic simple-sequence-repeat (SSR) markers were identified, with 72 of them being chromosome- or chromosome-arm-specific, 16 mapping to more than one chromosome, and 71 mapping to all the Agropyron chromosomes. The markers were used to characterize orthologous relationships between A. cristatum and common wheat that will facilitate the introgression breeding of wheat using A. cristatum.

Epidemiological and molecular analysis of circulating fowl adenoviruses and emerging of serotypes 1, 3, and 8b in Egypt

Fowl adenoviruses (FAdVs) are a large group of viruses of different serotypes. They are responsible for inclusion body hepatitis, adenoviral gizzard erosion, and hepatitis hydropericardium syndrome. The present study presents a comprehensive overview of FAdVs in Egypt, with a focus on the epidemiological features of virus serotypes across the country. We conducted molecular investigation of multiple FAdV species based on the genetic signature of hypervariable regions 1–4 in the loop1 (L1) region of the hexon gene. Epidemiologically, the Nile Delta governorates showed high positivity of FAdVs, which were more commonly found in broilers than in layers. Genetically, species D and serotype 8a/E dominated, and the findings also revealed the emergence of new FAdV serotypes 1, 3, and 8b. The comparative analysis of hypervariable regions in the L1 region of the hexon gene revealed variables specific to each virus serotype. In silico predictions of L1 region revealed variations in the molecular structure and predicted the antigenic epitopes which may affect the cross-antigenicity between the different FAdV species and serotypes.

Association between family history and severity of coronary artery disease in a nationwide sample of patients with a first time myocardial infarction

 

Having an early family history of coronary artery disease (CAD) is strongly associated with incident cardio-vascular disease. In younger patients with acute coronary syndrome, an association between family history and the severity of CAD, determined by the number of affected coronary arteries diagnosed through coronary angiography, has been reported. However, it is unknown if these findings apply to unselected patients with a first-time myocardial infarction (MI) and whether an early family history of other atherosclerotic cardiovascular diseases (ASCVD) affect CAD severity. Therefore, our objective was to investigate the association between a family history of ASCVD and the extent of CAD determined by coronary angiography findings in a large nationwide sample of patients with a first-time MI.

Material and methods

This study included a consecutive sample of 22,686 one-year survivors of first-ever MI aged, 18 to 76 years, identified in the national register SWEDEHEART. Attending the standardized 1-year revisit after MI, from 2006 through 2013. First-degree relatives, defined as parents and full siblings, were identified in the Swedish Multi-Generation Register and data on historical hospitalisations and deaths were extracted. The exposure was defined as having a first-degree relative with records of early ASCVD, defined as a register-verified hospitalisation due to myocardial infarction, any angina with coronary revascularization, stroke or cardiovascular death before the age of 55 in male or 65 years in female relatives. The primary outcome was severity of CAD categorized to four groups: zero-, single-, two- or three-vessel disease as registered in SWEDE-HEART. Left main stem disease was included in the three-vessel category. The distribution of the CAD severity categories was compared between those with and without an early family history of ASCVD using multinomial logistic regression, adjusted for age and sex and using single-vessel disease as the reference group.

Results

We included 22 686 participants (median age 63 [IQR 57–68] years; 27% women), of which 1450 had a family history of early ASCVD. A total of 2134 patients did not have any significant obstructive findings at the first coronary angiography, 10 951 patients had single-vessel disease, 5516 patients had two-vessel disease and 3970 patients had three-vessel or main stem disease. Both two-vessel disease (RRR 1.31, 95% CI 1.14–1.50) and three vessel and/or left main stem disease (RRR 1.29, 95% CI 1.1–1.51) were more common in patients with early family history of ASCVD when adjusting for age and sex, whereas no significant angiographic disease was less common (RRR 0.76, 95% 0.61–0.95).

Conclusion

Patients with a first-time MI and a family history of early ASCVD have an approximately 30% higher risk of advanced coronary artery disease, with more than two affected coronary vessels or left main stem disease.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The Swedish Heart and Lung Association (Riksförbundet HjärtLung) Graph 1

Investigating the need for therapeutic drug monitoring of imipenem in critically ill patients: Are we getting it right?

BACKGROUND

The drug levels and clearances of imipenem in critically ill patients are not comprehensively described in current literature, yet it is vital that adequate levels be achieved for therapeutic success.

OBJECTIVES

To determine the proportion of critically ill patients treated with imipenem/cilastatin with sub-therapeutic imipenem plasma levels, and to compare the clinical outcomes of those patients with therapeutic levels with those who had sub-therapeutic levels.

METHODS

Trough imipenem plasma levels of 68 critically ill patients from a surgical intensive care unit were measured using a validated high-performance liquid chromatography method. Imipenem trough levels were compared with the minimum inhibitory concentration (MIC) of the causative bacterial agents, based on a target value of 100% time above MIC (¦T >MIC).

RESULTS

The proportion of participants with sub-therapeutic imipenem levels was 22% (95% confidence interval (CI) 13% - 34%). The 14- and 28-day mortality rates in the sub-therapeutic group were 33% and 40%, respectively, compared with 19% (p=0.293) and 26% (p=0.346), respectively, in the therapeutic group. Sub-therapeutic imipenem plasma levels are associated with adjusted hazard ratio of 1.47 (95% CI 0.55 - 3.91).

CONCLUSIONS

The lower proportion of critically ill patients with sub-therapeutic imipenem plasma levels in this study compared with previous studies may be attributed to the practice of higher dosages and the administration method of extended infusions of imipenem/cilastatin in our setting. The results demonstrate a trend of higher mortality in patients with sub-therapeutic imipenem levels, although the results were not statistically significant at this sample size.

Development of DNA Markers From Physically Mapped Loci in Aegilops comosa and Aegilops umbellulata Using Single-Gene FISH and Chromosome Sequences

Breeding of agricultural crops adapted to climate change and resistant to diseases and pests is hindered by a limited gene pool because of domestication and thousands of years of human selection. One way to increase genetic variation is chromosome-mediated gene transfer from wild relatives by cross hybridization. In the case of wheat (Triticum aestivum), the species of genus Aegilops are a particularly attractive source of new genes and alleles. However, during the evolution of the Aegilops and Triticum genera, diversification of the D-genome lineage resulted in the formation of diploid C, M, and U genomes of Aegilops. The extent of structural genome alterations, which accompanied their evolution and speciation, and the shortage of molecular tools to detect Aegilops chromatin hamper gene transfer into wheat. To investigate the chromosome structure and help develop molecular markers with a known physical position that could improve the efficiency of the selection of desired introgressions, we developed single-gene fluorescence in situ hybridization (FISH) maps for M- and U-genome progenitors, Aegilops comosa and Aegilops umbellulata, respectively. Forty-three ortholog genes were located on 47 loci in Ae. comosa and on 52 loci in Ae. umbellulata using wheat cDNA probes. The results obtained showed that M-genome chromosomes preserved collinearity with those of wheat, excluding 2 and 6M containing an intrachromosomal rearrangement and paracentric inversion of 6ML, respectively. While Ae. umbellulata chromosomes 1, 3, and 5U maintained collinearity with wheat, structural reorganizations in 2, 4, 6, and 7U suggested a similarity with the C genome of Aegilops markgrafii. To develop molecular markers with exact physical positions on chromosomes of Aegilops, the single-gene FISH data were validated in silico using DNA sequence assemblies from flow-sorted M- and U-genome chromosomes. The sequence similarity search of cDNA sequences confirmed 44 out of the 47 single-gene loci in Ae. comosa and 40 of the 52 map positions in Ae. umbellulata. Polymorphic regions, thus, identified enabled the development of molecular markers, which were PCR validated using wheat-Aegilops disomic chromosome addition lines. The single-gene FISH-based approach allowed the development of PCR markers specific for cytogenetically mapped positions on Aegilops chromosomes, substituting as yet unavailable segregating map. The new knowledge and resources will support the efforts for the introgression of Aegilops genes into wheat and their cloning.

The B chromosome of Sorghum purpureosericeum reveals the first pieces of its sequence

More than a century has passed since the B chromosomes were first discovered. Today we know much of their variability, morphology, and transmission to plant progeny. With the advent of modern technologies, B chromosome research has accelerated, and some of their persistent mysteries have since been uncovered. Building on this momentum, here we extend current knowledge of B chromosomes in Sorghum purpureosericeum to the sequence level. To do this, we estimated the B chromosome size at 421 Mb, sequenced DNA from flow-sorted haploid pollen nuclei of both B-positive (B+) and B-negative (B0) plants, and performed a repeat analysis on the Illumina raw sequence data. This analysis revealed nine putative B-specific clusters, which were then used to develop B chromosome-specific markers. Additionally, cluster SpuCL4 was identified and verified to be a centromeric repeat. We also uncovered two repetitive clusters (SpuCL168 and SpuCL115), which hybridized exclusively on the B chromosome under fluorescence in situ hybridization and can be considered as robust cytogenetic markers. Given that B chromosomes in Sorghum are rather unstable across all tissues, our findings could facilitate expedient identification of B+ plants and enable a wide range of studies to track this chromosome type in situ.

The B chromosome of Sorghum purpureosericeum reveals the first pieces of its sequence

More than a century has passed since the B chromosomes were first discovered. Today we know much of their variability, morphology, and transmission to plant progeny. With the advent of modern technologies, B chromosome research has accelerated, and some of their persistent mysteries have since been uncovered. Building on this momentum, here we extend current knowledge of B chromosomes in Sorghum purpureosericeum to the sequence level. To do this, we estimated the B chromosome size at 421 Mb, sequenced DNA from flow-sorted haploid pollen nuclei of both B-positive (B+) and B-negative (B0) plants, and performed a repeat analysis on the Illumina raw sequence data. This analysis revealed nine putative B-specific clusters, which were then used to develop B chromosome-specific markers. Additionally, cluster SpuCL4 was identified and verified to be a centromeric repeat. We also uncovered two repetitive clusters (SpuCL168 and SpuCL115), which hybridized exclusively on the B chromosome under fluorescence in situ hybridization and can be considered as robust cytogenetic markers. Given that B chromosomes in Sorghum are rather unstable across all tissues, our findings could facilitate expedient identification of B+ plants and enable a wide range of studies to track this chromosome type in situ.

Standardized delivery room management for neonates with a prenatal diagnosis of congenital heart disease: A model for improving interdisciplinary delivery room care

Precise characterization of cardiac anatomy and physiology through fetal echocardiography can predict early postnatal clinical course. Some neonates with prenatally defined critical congenital heart disease have anticipated precipitous compromise during perinatal transition for which specialized, diagnosis-specific delivery room care can be arranged to expeditiously stabilize cardiopulmonary hemodynamics. In this article, we describe our institutional approach to the delivery room care of neonates with prenatally diagnosed congenital heart disease, emphasizing our diagnosis-specific care pathways for newborns with critical disease.

Efficacy of Bivalent Inactivated Vaccine Containing Insect Cell-Expressed Avian Influenza H5 and Egg-Based Newcastle Disease Virus (NDV) Against Dual Infection with Highly Pathogenic H5N1 and Velogenic NDV in Chickens

The genetic evolution of highly pathogenic avian influenza (HPAI) in Egypt has developed a new clade H5N1 (2.2.1.2) since 2014. Meanwhile, the new avian influenza virus (AIV) clade mutually with the velogenic Newcastle disease virus (NDV) isolate of genotype VII in Egypt (genotype VII) has resulted in severe economic losses in the broiler industry. An inactivated bivalent vaccine containing H5 (belonging to H5N1 clade 2.3.2) recombinant baculovirus expressed by insect cell (recH5) and egg-based NDV LaSota strain (recH5/NDV vaccine) was evaluated for protection against the challenge of dual HPAIV H5N1 clade 2.2.1.2 and vNDV infection in commercial broiler chickens. Vaccination was performed when chickens were 10 days old, and then birds of the respective groups were challenged with 10⁶ 50% egg infective dose per chicken of each virus in 100 µl of allantoic fluid via the intranasal route at 21 days postvaccination in a single or sequential infection of both viruses. Results showed that the recH5/NDV vaccine was able to protect chickens against single or dual challenges of both viruses ranging up to 90%-100%. Unvaccinated chickens have demonstrated 100% mortalities to a single virus challenge. Vaccinated chickens showed significant decreases in both viruses, shedding titers up to <2 log ₁₀ after challenge in comparison with unvaccinated ones. Cessation of viral shedding was obtained at 7 to 10 days postchallenge. The vaccinated chickens showed high hemagglutination inhibition antibody titers >6 log ₂ against both H5N1 and NDV antigens at 2 wk postvaccination. The single vaccination of bivalent inactivated recH5-NDV vaccine at 10 days old in commercial chickens has provided significant clinical protective immunity against single or dual challenge with HPAI-H5N1clade 2.2.1.2 and vNDV-genotype VII.

Amisulpride-induced agranulocytosis: A case report

Introduction

Agranulocytosis is a potentially life-threatening haematological side effect induced by typical and atypical neuroleptic. When agranulocytosis is associated with a specific anti-psychotic, the medication should be discontinued. This severe side effect is troublesome.

Case report

We report the case of a 60-year-old man, treated with amisulpride for schizophrenia, who developed an agranulocytosis. This patient had been treated with first and second generation anti-psychotic drugs during his life and had already been exposed to many neuroleptics without any signs of toxicity. However, after three days of the introduction of amisulpride he presented a rapid onset agranulocytosis (leukocytes 1.2 G/L and neutrophils 0.4 G/L). After discontinuation of amisulpride, blood count returned to normal. The favorable evolution after discontinuation of treatment: the normality of biological and cytological examinations is in favor of a causal relationship between this severe neutropenia al introduction of amisulpride.

Conclusion

This case report highlights the risk of amisulpride in inducing agranulocytosis, a risk underestimated in regard of the clozapine risk to induce agranulocytosis or neutropenia. For this reason, it seems reasonable to recommend performing a blood count before introduction and during the treatment by anti-psychotics.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

A DFT study of Janus structure of S and Se in HfSSe layered as a promising candidate for electronic devices

The transition-metal dichalcogenides are presently being intensively researched because of their unique optoelectronic properties. Further, the success of TMDs in all areas of science without exception has opened the street to find other two-dimensional materials. Based on density functional theory, we study the vibrational and electronic properties of the mixed-phase of S and Se in HfSSe system, i.e, HfSSe monolayer and HfSSe/HfSSe bilayer. In this framework, our systems are full dynamically stable, which shown by their phonon dispersion. Also, we found that the HfSSe (heterolayer) monolayer is an indirect semiconductor (0.63 eV with BLYP), while the HfSSe (alternating) monolayer is a direct semiconductor (0.753 eV with BLYP). Our AA, AB, AA', and AB' of HfSSe/HfSSe (heterolayer) bilayer are indirect band gaps in a range 0.361-0.830 eV, which are promising candidates for electronic devices as field-effect transistors, photodetectors, and other optoelectronics. Nevertheless, HfSSe/HfSSe (alternating) bilayer is a direct bandgap semiconductor with a value of 0.671 eV, when vdW is used.

Uncovering homeologous relationships between tetraploid Agropyron cristatum and bread wheat genomes using COS markers

Using COS markers, the study reveals homeologous relationships between tetraploid Agropyron cristatum and bread wheat to support alien introgression breeding of wheat. Crested wheatgrass (Agropyron cristatum L. Gaertn.) is a wild relative of wheat that possesses many genes that are potentially useful in wheat improvement. The species comprises a complex of diploid, tetraploid and hexaploid forms. In this study, wheat-A. cristatum chromosome, telosome and translocation lines were used to characterize syntenic relationships between tetraploid A. cristatum and bread wheat. Prior to mapping COS markers, the cytogenetic stock lines were characterized for fertility and by FISH and GISH for karyotype stability. Out of 328 COS markers selected for the study, 279 consistently amplified products in tetraploid A. cristatum, and, out of these, 139 were polymorphic between tetraploid crested wheatgrass and wheat. Sixty-nine markers were found to be suitable for the detection of tetraploid A. cristatum chromosomes 1P-6P in wheat, ranging from 6 to 17 markers per chromosome. BLASTn of the source ESTs resulted in significant hits for 67 markers on the wheat pseudomolecules. Generally, COS markers of the same homeologous group were detected on similar arms in both Agropyron and wheat. However, some intragenomic duplications and chromosome rearrangements were detected in tetraploid A. cristatum. These results provide new insights into the structure and evolution of the tetraploid A. cristatum genome and will facilitate the exploitation of the wild species for introgression breeding of bread wheat.

Dissecting the Complex Genome of Crested Wheatgrass by Chromosome Flow Sorting

Wheatgrass (Agropyron sp.) is a potential source of beneficial traits for wheat improvement. Among them, crested wheatgrass [A. cristatum (L.) Gaertn.] comprises a complex of diploid, tetraploid, and hexaploid forms with the basic genome P, with some accessions carrying supernumerary B chromosomes (Bs). In this work, we applied flow cytometry to dissect the complex genome of crested wheatgrass into individual chromosomes to facilitate its analysis. Flow karyotypes obtained after the analysis of 4',6-diamidino-2-phenylindole (DAPI)-stained mitotic chromosomes of diploid and tetraploid accessions consisted of three peaks, each corresponding to a group of two or three chromosomes. To improve the resolution, bivariate flow karyotyping after fluorescent labeling of chromosomes with fluorescein isothiocyanate (FITC)-conjugated probe (GAA) microsatellite was applied and allowed discrimination and sorting of P genome chromosomes from wheat-crested wheatgrass addition lines. Chromosomes 1P-6P and seven telomeric chromosomes could be sorted at purities ranging from 81.7 to 98.2% in disomics and from 44.8 to 87.3% in telosomics. Chromosome 7P was sorted at purities reaching 50.0 and 39.5% in diploid and tetraploid crested wheatgrass, respectively. In addition to the whole complement chromosomes (A), Bs could be easily discriminated and sorted from a diploid accession at 95.4% purity. The sorted chromosomes will streamline genome analysis of crested wheatgrass, facilitating gene cloning and development of molecular tools to support alien introgression into wheat.

[An evolutionist approach of mood disorders from a transcultural perspective]

INTRODUCTION

The objective of this paper is to verify if traits and symptoms defined as pathological and maladjusted in certain contexts may produce adaptive effects in other contexts, especially if they occur in sub-threshold forms.

METHODS

A historical examination of how the symptoms of depression have changed in front of great social changes and an analysis of Sardinian migrants' thymic profiles toward several metropolises.

RESULTS AND CONCLUSIONS

Mood disorders have been increasing since the "English malady" in the 17th century, and we suppose that some forms of mood disorders might have an adaptive advantage. Otherwise, the increase of such an epidemic would have been self-limited. From a sociobiological point of view, it is highly probable that the environment of a rapidly evolving society can select people who are explorers and able to support accelerated biorhythms and that the condition of social change stimulates psychological and psychopathologic changes. It is also possible that hyperthymic persons modulate and create the new environment. If this model can explain the epidemic of mood disorders, its verification should guide future research.

The Agropyron cristatum karyotype, chromosome structure and cross-genome homoeology as revealed by fluorescence in situ hybridization with tandem repeats and wheat single-gene probes

Fluorescence in situ hybridization with probes for 45 cDNAs and five tandem repeats revealed homoeologous relationships of Agropyron cristatum with wheat. The results will contribute to alien gene introgression in wheat improvement. Crested wheatgrass (Agropyron cristatum L. Gaertn.) is a wild relative of wheat and a promising source of novel genes for wheat improvement. To date, identification of A. cristatum chromosomes has not been possible, and its molecular karyotype has not been available. Furthermore, homoeologous relationship between the genomes of A. cristatum and wheat has not been determined. To develop chromosome-specific landmarks, A. cristatum genomic DNA was sequenced, and new tandem repeats were discovered. Their distribution on mitotic chromosomes was studied by fluorescence in situ hybridization (FISH), which revealed specific patterns for five repeats in addition to 5S and 45S ribosomal DNA and rye subtelomeric repeats pSc119.2 and pSc200. FISH with one tandem repeat together with 45S rDNA enabled identification of all A. cristatum chromosomes. To analyze the structure and cross-species homoeology of A. cristatum chromosomes with wheat, probes for 45 mapped wheat cDNAs covering all seven chromosome groups were localized by FISH. Thirty-four cDNAs hybridized to homoeologous chromosomes of A. cristatum, nine hybridized to homoeologous and non-homoeologous chromosomes, and two hybridized to unique positions on non-homoeologous chromosomes. FISH using single-gene probes revealed that the wheat-A. cristatum collinearity was distorted, and important structural rearrangements were observed for chromosomes 2P, 4P, 5P, 6P and 7P. Chromosomal inversions were found for pericentric region of 4P and whole chromosome arm 6PL. Furthermore, reciprocal translocations between 2PS and 4PL were detected. These results provide new insights into the genome evolution within Triticeae and will facilitate the use of crested wheatgrass in alien gene introgression into wheat.

Neuropathy by folic acid supplementation in a patient with anaemia and an untreated cobalamin deficiency: a case report

The rising rates of bariatric surgery (BS) are accompanied by neurological complications related to nutrient deficiencies. One of the risk factors for neurological complications in BS patients is poor vitamin and mineral supplementation. Prevention, diagnosis and treatment of these disorders are necessary parts of lifelong care after BS. Particularly important for optimal functioning of the nervous system are vitamin B₁ , B₆ , B₁₂ (cobalamin), E, copper and possibly vitamin B₁₁ (folic acid). In this case report, we narrate about a patient with anaemia and multiple vitamin and mineral deficiencies after Roux-en-Y gastric bypass (RYGB) with an alimentary limb of 150 cm and a biliopancreatic limb of 100 cm. RYGB is associated with an increased risk of vitamin deficiencies, especially a vitamin B₁₂ deficiency. The patient in this case report developed psychiatric-neurological symptoms due to folic acid supplementation in an untreated cobalamin deficiency. Second, we tried to elucidate the vitamin physiology to understand specific mechanisms after BS.

The adverse effects of interferon-free regimens in 149 816 chronic hepatitis C treated Egyptian patients

BACKGROUND

Interferon-free regimens are associated with high sustained virological response; however, associated adverse effects have yet to be fully reported.

AIM

To evaluate the adverse effects associated with the different direct-acting antiviral drug (DAA) regimens in Egyptian patients.

METHODS

This multicenter retrospective study included all adverse effects during and after treatment with DAA regimens of 149 816 chronic hepatitis C treated Egyptian patients. Patients received sofosbuvir (SOF)/ribavirin (RBV) (n = 21 835), SOF/simeprevir (n = 24 215) SOF/daclatasvir (DCV) (n = 58 477), SOF/DCV/RBV (n = 45 188) and paritaprevir/ombitasvir/ritonavir/RBV (n = 101). The duration of treatment varied between 12 and 24 weeks. All changes in the treatment regimens, discontinuation, mortality, and serious side effects were reported.

RESULTS

Adverse effects developed in 2475 (1.7%) (mean age [54 ± 9], male gender [53%]) patients. Serious side effects developed in 68% of these patients, and SOF/RBV was the most common causing regimen (73%, P < 0.001). Anaemia and hyperbilirubinemia were the most common side effects (731/149816, 0.5% and 463/149816, 0.3%, respectively) and SOF/RBV (588/21835, 3% and 353/21835, 1.6%, respectively) showed the highest incidence in the treated patients. Hepatocellular carcinoma and mortality were reported in 0.02% and 0.06% of all treated patients, respectively. Patients with liver cirrhosis showed higher incidence of serious side effects (Log rank P = 0.045) and mortality (Log rank P = 0.025) than patients without liver cirrhosis. Male gender (P = 0.012), lower haemoglobin (P < 0.001), platelets (P < 0.001) and albumin (P = 0.001), higher bilirubin (P = 0.002) and cirrhosis (P < 0.001) were factors associated with serious side effects development.

CONCLUSION

Adverse effects associated with DAAs are few, anaemia being the most common. SOF/RBV regimen showed the highest rate of side effects while SOF/DCV showed the least.

Lipoedema in patients after bariatric surgery: report of two cases and review of literature

Lipoedema is a disorder of adipose tissue that is characterized by abnormal subcutaneous fat deposition, leading to swelling and enlargement of the lower limbs as well as the trunk. This entity is often misdiagnosed as lymphoedema or obesity and, therefore, may be overlooked and missed in patients scheduled for bariatric surgery. Patients with lipoedema who undergo bariatric surgery may have to continue to have extensive lower extremity and trunk adiposity despite adequate weight loss. In this report, we present two patients who had extensive trunk and lower extremity adiposity, one of them before and the other after the bariatric surgery.

Local disease-ecosystem-livelihood dynamics: reflections from comparative case studies in Africa

This article explores the implications for human health of local interactions between disease, ecosystems and livelihoods. Five interdisciplinary case studies addressed zoonotic diseases in African settings: Rift Valley fever (RVF) in Kenya, human African trypanosomiasis in Zambia and Zimbabwe, Lassa fever in Sierra Leone and henipaviruses in Ghana. Each explored how ecological changes and human–ecosystem interactions affect pathogen dynamics and hence the likelihood of zoonotic spillover and transmission, and how socially differentiated peoples’ interactions with ecosystems and animals affect their exposure to disease. Cross-case analysis highlights how these dynamics vary by ecosystem type, across a range from humid forest to semi-arid savannah; the significance of interacting temporal and spatial scales; and the importance of mosaic and patch dynamics. Ecosystem interactions and services central to different people's livelihoods and well-being include pastoralism and agro-pastoralism, commercial and subsistence crop farming, hunting, collecting food, fuelwood and medicines, and cultural practices. There are synergies, but also tensions and trade-offs, between ecosystem changes that benefit livelihoods and affect disease. Understanding these can inform ‘One Health’ approaches towards managing ecosystems in ways that reduce disease risks and burdens.

This article is part of the themed issue ‘One Health for a changing world: zoonoses, ecosystems and human well-being’.

Generic daclatasvir plus sofosbuvir, with or without ribavirin, in treatment of chronic hepatitis C: real-world results from 18 378 patients in Egypt

BACKGROUND

Treatment of chronic hepatitis C using combination of sofosbuvir (SOF) and daclatasvir (DCV) was used in several clinical trials and multicentre studies, which were somewhat limited to genotypes 1-3. The national program in Egypt is using SOF-DCV combination for large scale treatment.

AIM

To assess the efficacy and safety of combined SOF-DCV in treating patients with HCV-G4 in a real-world setting.

METHODS

Data and outcome of chronic HCV patients who were treated for 12 weeks with generic medications: DCV 60 mg plus SOF 400 mg ± ribavirin (RBV) within the national hepatitis C treatment program in Egypt are presented. Treatment-naïve patients without cirrhosis were treated without RBV, and those who had cirrhosis or were treatment-experienced (interferon experienced or SOF experienced) received RBV. Efficacy and safety were assessed, and baseline factors associated with sustained virological response at post-treatment week 12 (SVR12) were explored.

RESULTS

During the first 2 months of the programme, 18 378 patients with HCV-G4 started treatment with SOF-DCV with or without RBV. Overall, 95.1% achieved SVR12 (95.4% among patients treated without RBV and 94.7% for patients treated with RBV, P = .32). Treatment was prematurely discontinued in only 1.5% of patients. The most common events leading to discontinuation were patient withdrawal (n = 76) and pregnancy (n = 5). Five deaths occurred within this group.

CONCLUSIONS

Real-world experience of generic SOF-DCV in patients with chronic HCV-G4 proved to be safe and associated with a high SVR12 rate, in patients with different stages of fibrosis.

Early effects of Epac depend on the fine-tuning of the sarcoplasmic reticulum Ca2+ handling in cardiomyocytes

In cardiac muscle, signaling through cAMP governs many fundamental cellular functions, including contractility, relaxation and automatism. cAMP cascade leads to the activation of the classic protein kinase A but also to the stimulation of the recently discovered exchange protein directly activated by cAMP (Epac). The role of Epac in the regulation of intracellular Ca²⁺ homeostasis and contractility in cardiac myocytes is still matter of debate. In this study we showed that the selective Epac activator, 8-(4-chloro-phenylthio)-2'-O-methyladenosine-3', 5'-cyclic monophosphate (8-CPT), produced a positive inotropic effect when adult rat cardiac myocytes were stabilized at low [Ca²⁺]_o (0.5mM), no changes at 1mM [Ca²⁺]_o and a negative inotropic effect when [Ca²⁺]_o was increased to 1.8mM. These effects were associated to parallel variations in sarcoplasmic reticulum (SR) Ca²⁺ content. At all [Ca²⁺]_o studied, 8-CPT induced an increase in Ca²⁺ spark frequency and enhanced CaMKII autophosphorylation and the CaMKII-dependent phosphorylation of SR proteins: phospholamban (PLN, at Thr17 site) and ryanodine receptor (RyR2, at Ser2814 site). We used transgenic mice lacking PLN CaMKII phosphorylation site (PLN-DM) and knock-in mice with an inactivated CaMKII site S2814 on RyR2 (RyR2-S2814A) to investigate the involvement of these processes in the effects of Epac stimulation. In PLN-DM mice, 8-CPT failed to induce the positive inotropic effect at low [Ca²⁺]_o and RyR2-S2814A mice showed no propensity to arrhythmic events when compared to wild type mice myocytes. We conclude that stimulation of Epac proteins could have either beneficial or deleterious effects depending on the steady-state Ca²⁺ levels at which the myocyte is functioning, favoring the prevailing mechanism of SR Ca²⁺ handling (uptake vs. leak) in the different situations.