Salt Tolerance of Sea Flax (Linum maritimum L.), a Rare Species with Conservation Interest in Eastern Spain

Seldom found in saltmarshes, Linum maritimum is a halophyte of great conservation interest in the eastern Iberian Peninsula. Although the species has been reported in different plant communities, there is no information on its range of salinity tolerance or mechanisms of response to environmental stress factors. In this study, L. maritimum plants were subjected to increasing salt concentrations in controlled conditions in a greenhouse. After six months of watering with salt solutions, only plants from the control, 50 mM and 100 mM NaCl treatment groups survived, but seeds were produced only in the first two. Significant differences were found between the plants from the various treatment groups in terms of their growth parameters, such as plant height, fresh weight, and the quantity of flowers and fruits. The main mechanism of salt tolerance is probably related to the species' ability to activate K+ uptake and transport to shoots to partly counteract the accumulation of toxic Na+ ions. A biochemical analysis showed significant increases in glycine betaine, flavonoids and total phenolic compounds, highlighting the importance of osmotic regulation and antioxidant compounds in the salt tolerance of Linum maritimum. These findings have implications for the conservation of the species, especially under changing climatic conditions that may lead to increased soil salinity in its Mediterranean distribution area.

The Highly Embryogenic Brassica napus DH4079 Line Is Recalcitrant to Agrobacterium-Mediated Genetic Transformation

Brassica napus is a species of high agronomic interest, used as a model to study different processes, including microspore embryogenesis. The DH4079 and DH12075 lines show high and low embryogenic response, respectively, which makes them ideal to study the basic mechanisms controlling embryogenesis induction. Therefore, the availability of protocols for genetic transformation of these two backgrounds would help to generate tools to better understand this process. There are some reports in the literature showing the stable transformation of DH12075. However, no equivalent studies in DH4079 have been reported to date. We explored the ability of DH4079 plants to be genetically transformed. As a reference to compare with, we used the same protocols to transform DH12075. We used three different protocols previously reported as successful for B. napus stable transformation with Agrobacterium tumefaciens and analyzed the response of plants. Whereas DH12075 plants responded to genetic transformation, DH4079 plants were completely recalcitrant, not producing any single regenerant out of the 1784 explants transformed and cultured. Additionally, an Agrobacterium rhizogenes transient transformation assay was performed on both lines, and only DH12075, but no DH4079 seedlings, responded to A. rhizogenes infection. Therefore, we propose that the DH4079 line is recalcitrant to Agrobacterium-mediated transformation.

Calcium dynamics and modulation in carrot somatic embryogenesis

Free calcium (Ca²⁺) is a pivotal player in different in vivo and in vitro morphogenic processes. In the induction of somatic embryogenesis, its role has been demonstrated in different species. In carrot, however, this role has been more controversial. In this work, we developed carrot lines expressing cameleon Ca²⁺ sensors. With them, Ca²⁺ levels and distribution in the different embryogenic structures formed during the induction and development of somatic embryos were analyzed by FRET. We also used different chemicals to modulate intracellular Ca²⁺ levels (CaCl₂, ionophore A23187, EGTA), to inhibit calmodulin (W-7) and to inhibit callose synthesis (2-deoxy-D-glucose) at different times, principally during the first stages of embryo induction. Our results showed that high Ca²⁺ levels and the development of a callose layer are markers of cells induced to embryogenesis, which are the precursors of somatic embryos. Disorganized calli and embryogenic masses have different Ca²⁺ patterns associated to their embryogenic competence, with higher levels in embryogenic cells than in callus cells. The efficiency of somatic embryogenesis in carrot can be effectively modulated by allowing, within a range, more Ca²⁺ to enter the cell to act as a second messenger to trigger embryogenesis induction. Once induced, Ca²⁺-calmodulin signaling seems related with the transcriptional remodeling needed for embryo progression, and alterations of Ca²⁺ or calmodulin levels negatively affect the efficiency of the process.

Calcium Dynamics, WUSCHEL Expression and Callose Deposition during Somatic Embryogenesis in Arabidopsis thaliana Immature Zygotic Embryos

In this work, we studied the induction of somatic embryogenesis in Arabidopsis using IZEs as explants. We characterized the process at the light and scanning electron microscope level and studied several specific aspects such as WUS expression, callose deposition, and principally Ca²⁺ dynamics during the first stages of the process of embryogenesis induction, by confocal FRET analysis with an Arabidopsis line expressing a cameleon calcium sensor. We also performed a pharmacological study with a series of chemicals know to alter calcium homeostasis (CaCl₂, inositol 1,4,5-trisphosphate, ionophore A23187, EGTA), the calcium-calmodulin interaction (chlorpromazine, W-7), and callose deposition (2-deoxy-D-glucose). We showed that, after determination of the cotiledonary protrusions as embryogenic regions, a finger-like appendix may emerge from the shoot apical region and somatic embryos are produced from the WUS-expressing cells of the appendix tip. Ca²⁺ levels increase and callose is deposited in the cells of the regions where somatic embryos will be formed, thereby constituting early markers of the embryogenic regions. We also found that Ca²⁺ homeostasis in this system is strictly maintained and cannot be altered to modulate embryo production, as shown for other systems. Together, these results contribute to a better knowledge and understanding of the process of induction of somatic embryos in this system.

Constitutive and Adaptive Traits of Environmental Stress Tolerance in the Threatened Halophyte Limonium angustebracteatum Erben (Plumbaginaceae)

Limonium angustebracteatum is a halophyte endemic to the E and SE Iberian Peninsula with interest in conservation. Salt glands represent an important adaptive trait in recretohalophytes like this and other Limonium species, as they allow the excretion of excess salts, reducing the concentration of toxic ions in foliar tissues. This study included the analysis of the salt gland structure, composed of 12 cells, 4 secretory and 8 accessory. Several anatomical, physiological and biochemical responses to stress were also analysed in adult plants subjected to one month of water stress, complete lack of irrigation, and salt stress, by watering with aqueous solutions of 200, 400, 600 and 800 mM NaCl. Plant growth was inhibited by the severe water deficit and, to a lesser extent, by high NaCl concentrations. A variation in the anatomical structure of the leaves was detected under conditions of salt and water stress; plants from the salt stress treatment showed salt glands sunken between epidermal cells, bordered by very large epidermal cells, whereas in those from the water stress treatment, the epidermal cells were heterogeneous in shape and size. In both, the palisade structure of the leaves was altered. Salt excretion is usually accompanied by the accumulation of salts in the foliar tissue. This was also found in L. angustebracteatum, in which the concentration of all ions analysed was higher in the leaves than in the roots. The increase of K⁺ in the roots of plants subjected to water stress was also remarkable. The multivariate analysis indicated differences in water and salt stress responses, such as the accumulation of Na and Cl, or proline, but K⁺ homeostasis played a relevant role in the mechanism of tolerance to both stressful conditions.

Significant Association of Antiepileptic Drug Polytherapy with Decreased FT4 Levels in Epileptic Patients

Epileptic patients have to continue anti-epileptic drugs (AED) over a long period of time which can have deleterious effects on the endocrine system including the thyroid hormones with rare check. Risk factors for the development of thyroid dysfunction are still unclear. Therefore the aim of study was to evaluate thyroid functions in epileptic patients receiving anti-epileptic drugs (AED) as monotherapy and polytherapy and to determine potential risk of low thyroid function in epileptic patients receiving treatment. This cross-sectional study included 100 epilepsy patients more than 12 years of age. Serum levels of free thyroxin (FT4), free triiodothyronine (FT3), and thyroid stimulating hormone (TSH) were evaluated in all subjects in addition to serum AED levels. TSH levels were found to be significantly higher in the polytherapy subgroup (p < 0.05) in comparison to the monotherapy group. 44% of the patients in the VPA monotherapy group had raised TSH levels and 41.2% of the patients on CBZ had low FT4. A significant negative correlation was observed between CBZ and FT4 (p < 0.05). Female sex and old age were additional risk factors detected for deranged thyroid function. Female patients with epilepsy, an older age and AED polytherapy were found to be associated with a higher risk of thyroid dysfunction. Thus, Thyroid function in these patients should be monitored closely. In conclusion, we observed significant changes in thyroid hormone levels in patients receiving antiepileptic treatment in both monotherapy and polytherapy. Elevated CBZ levels were significantly associated with decreased FT4 levels.

Cell Wall Composition and Structure Define the Developmental Fate of Embryogenic Microspores in Brassica napus

Microspore cultures generate a heterogeneous population of embryogenic structures that can be grouped into highly embryogenic structures [exine-enclosed (EE) and loose bicellular structures (LBS)] and barely embryogenic structures [compact callus (CC) and loose callus (LC) structures]. Little is known about the factors behind these different responses. In this study we performed a comparative analysis of the composition and architecture of the cell walls of each structure by confocal and quantitative electron microscopy. Each structure presented specific cell wall characteristics that defined their developmental fate. EE and LBS structures, which are responsible for most of the viable embryos, showed a specific profile with thin walls rich in arabinogalactan proteins (AGPs), highly and low methyl-esterified pectin and callose, and a callose-rich subintinal layer not necessarily thick, but with a remarkably high callose concentration. The different profiles of EE and LBS walls support the development as suspensorless and suspensor-bearing embryos, respectively. Conversely, less viable embryogenic structures (LC) presented the thickest walls and the lowest values for almost all of the studied cell wall components. These cell wall properties would be the less favorable for cell proliferation and embryo progression. High levels of highly methyl-esterified pectin are necessary for wall flexibility and growth of highly embryogenic structures. AGPs seem to play a role in cell wall stiffness, possibly due to their putative role as calcium capacitors, explaining the positive relationship between embryogenic potential and calcium levels.

Doubled Haploids in Eggplant

Eggplant is a solanaceous crop cultivated worldwide for its edible fruit. Eggplant breeding programs are mainly aimed to the generation of F1 hybrids by crossing two highly homozygous, pure lines, which are traditionally obtained upon several self crossing generations, which is an expensive and time consuming process. Alternatively, fully homozygous, doubled haploid (DH) individuals can be induced from haploid cells of the germ line in a single generation. Several attempts have been made to develop protocols to produce eggplant DHs principally using anther culture and isolated microspore culture. Eggplant could be considered a moderately recalcitrant species in terms of ability for DH production. Anther culture stands nowadays as the most valuable technology to obtain eggplant DHs. However, the theoretical possibility of having plants regenerated from somatic tissues of the anther walls cannot be ruled out. For this reason, the use of isolated microspores is recommended when possible. This approach still has room for improvement, but it is largely genotype-dependent. In this review, we compile the most relevant advances made in DH production in eggplant, their application to breeding programs, and the future perspectives for the development of other, less genotype-dependent, DH technologies.

Species with Haploid or Doubled Haploid Protocols

In this chapter, we present a list of species (and few interspecific hybrids) where haploids and/or doubled haploids have been published, including the method by which they were obtained and the corresponding references. This list is an update of the compilation work of Maluszynski et al. published in 2003, including new species for which protocols were not available at that time, and also novel methodologies developed during these years. The list includes 383 different backgrounds. In this book, we present full protocols to produce DHs in 43 of the species included in this list. In addition, this book includes a chapter for one species not included in the list. This makes a total of 384 species where haploids and/or DHs have been reported up to date.

Sacral Insufficiency Fracture Following Pelvic Radiotherapy in Gynaecological Malignancies: Development of a Predictive Model

AIMS

To investigate the time-to-event and the evolution of sacral insufficiency fractures in gynaecological patients receiving pelvic external beam radiotherapy (EBRT) in relation to dosimetric and imaging parameters across a spectrum of radiotherapy delivery techniques, and to develop a predictive model with a clinical nomogram to identify those at risk of sacral insufficiency fracture.

MATERIALS AND METHODS

Patients who received radical or adjuvant pelvic EBRT for gynaecological malignancy between 2014 and 2019 were identified. The data collected were: demographics and clinical details; radiotherapy planning data: dose, fractionation, technique (fixed-field intensity-modulated radiotherapy, adaptive arc, and non-adaptive arc), 60 Gy simultaneous integrated boost. Each plan was examined to determine the sacral dose in 5%/Gy₃ increments. Follow-up magnetic resonance scans were reviewed for insufficiency fractures, defined as linear low T1-weighted signal intensity with a high short-T1 inversion recovery (STIR) signal. The site of insufficiency fracture was recreated on the planning computed tomography, the dose to insufficiency fracture contours was recorded and insufficiency fractures were determined as healed with resolution of high STIR signal. Univariable analysis was conducted of the clinical variables. The area under the receiver operator characteristic curve and odds ratio of the risk prediction model with 95% confidence interval are reported with a nomogram for use in clinical practice.

RESULTS

115 patients were identified; the median imaging follow-up was 12 months (2-47). 37.4% developed sacral insufficiency fractures; 93.0% were detected within 12 months of EBRT. At the final radiological follow-up, 83.7% of insufficiency fractures remained active. The radiotherapy delivery technique was not associated with insufficiency fracture after adjusting for patient age (P = 0.115). The location of the 60 Gy simultaneous integrated boost planning target volume did not impact upon the site of insufficiency fracture or the dose received by the insufficiency fracture sites. Age and V40Gy₃ are predictors for insufficiency fracture and form the clinical risk model (receiver operator characteristic 0.72).

CONCLUSIONS

Age and V40Gy₃ predict sacral insufficiency fractures; future work should focus on optimising radiotherapy planning with adoption of a bone-sparing planning approach for those patients at high risk of insufficiency fracture.

Involvement of microRNA-423 Gene Variability in Breast Cancer Progression in Saudi Arabia

Aim:

microRNA-423 is an oncogenic factor which is frequently upregulated in cancer. However, associations with breast cancer risk remain inconsistent. Therefore, we investigated the prevalence of microRNA-423 rs6505162C>T gene variation with breast cancer susceptibility in Saudi women.

Methodology:

This study was conducted on 100 breast cancer patients and 124 matched healthy individuals. Genotyping of the microRNA-423 rs6505162C/T gene variation was performed by using the amplification refractory mutation system PCR method (ARMS-PCR).

Results:

A significant difference was observed in the genotype distribution between the breast cancer cases and controls (p=0.0001), the frequencies of the genotypes CC,CT and TT being 25%, 52% and 23% in patients and 65%,20% and 15% respectively, in controls. The microRNA-423 C>T variant was associated with an increased risk of breast cancer in codominant models for (OR = 6.73, 95 % CI, 3.50-12.97; RR 2.35(1.67-3.30, p=0.0001) the microRNA-423TT genotype and (OR = 4.14, 95 % CI, 1.93-8.87; p=0.0003) microRNA-423CT (OR= 6.73, 95% CI, 3.50-12.97; p=0.0001) and also with the dominant model (OR 5.6(3.14-1.01), p=0.0001) CT+TT vs CC) with a non-significant association for the recessive model (OR=1.75, 95%CI=0.08-3.44, P=0.139, TT vs CC+CT). The T allele significantly increased the risk of breast cancer (OR =2.63, 95 % CI, 1.77-3.91; p=0.001) compared to the C allele. Some 6.73 ,4.14 and 2.63 fold increased risk of developing breast cancer was associated with TT and CT genotypes and the T allele of microRNA-423 in the northwestern region of Saudi Arabia.

Conclusion:

Our findings indicate that the microRNA-423 TT genotype and the T allele are associated with an increased susceptibility, metastasis and advanced stage of breast cancer in Saudi Arabian patients. Further studies with larger sample sizes are necessary to confirm our findings.

Operating list composition and surgical performance

BACKGROUND

Recent reviews suggest that the way in which surgeons prepare for a procedure (warm up) can affect performance. Operating lists present a natural experiment to explore this phenomenon. The aim was to use a routinely collected large data set on surgical procedures to understand the relationship between case list order and operative performance.

METHOD

Theatre lists involving the 35 procedures performed most frequently by senior surgeons across 38 private hospitals in the UK over 26 months were examined. A linear mixed-effects model and matched analysis were used to estimate the impact of list order and the cost of switching between procedures on a list while controlling for key prognosticators. The influence of procedure method (open versus minimally invasive) and complexity was also explored.

RESULTS

The linear mixed-effects model included 255 757 procedures, and the matched analysis 48 632 pairs of procedures. Repeating the same procedure in a list resulted in an overall time saving of 0·98 per cent for each increase in list position. Switching between procedures increased the duration by an average of 6·48 per cent. The overall reduction in operating time from completing the second procedure straight after the first was 6·18 per cent. This pattern of results was consistent across procedure method and complexity.

CONCLUSION

There is a robust relationship between operating list composition and surgical performance (indexed by duration of operation). An evidence-based approach to structuring a theatre list could reduce the total operating time.

Division Plane Orientation Defects Revealed by a Synthetic Double Mutant Phenotype

TANGLED1 (TAN1) and AUXIN-INDUCED-IN-ROOTS9 (AIR9) are microtubule-binding proteins that localize to the division site in plants. Their function in Arabidopsis (Arabidopsis thaliana) remained unclear because neither tan1 nor air9 single mutants have a strong phenotype. We show that tan1 air9 double mutants have a synthetic phenotype consisting of short, twisted roots with disordered cortical microtubule arrays that are hypersensitive to a microtubule-depolymerizing drug. The tan1 air9 double mutants have significant defects in division plane orientation due to failures in placing the new cell wall at the correct division site. Full-length TAN1 fused to yellow fluorescent protein, TAN1-YFP, and several deletion constructs were transformed into the double mutant to assess which regions of TAN1 are required for its function in root growth, root twisting, and division plane orientation. TAN1-YFP expressed in tan1 air9 significantly rescued the double mutant phenotype in all three respects. Interestingly, TAN1 missing the first 126 amino acids, TAN1-ΔI-YFP, failed to rescue the double mutant phenotype, while TAN1 missing a conserved middle region, TAN1-ΔII-YFP, significantly rescued the mutant phenotype in terms of root growth and division plane orientation but not root twisting. We use the tan1 air9 double mutant to discover new functions for TAN1 and AIR9 during phragmoplast guidance and root morphogenesis.

A DII Domain-Based Auxin Reporter Uncovers Low Auxin Signaling during Telophase and Early G1

A sensitive and dynamically responsive auxin signaling reporter based on the DII domain of the INDOLE-3-ACETIC ACID28 (IAA28, DII) protein from Arabidopsis (Arabidopsis thaliana) was modified for use in maize (Zea mays). The DII domain was fused to a yellow fluorescent protein and a nuclear localization sequence to simplify quantitative nuclear fluorescence signal. DII degradation dynamics provide an estimate of input signal into the auxin signaling pathway that is influenced by both auxin accumulation and F-box coreceptor concentration. In maize, the DII-based marker responded rapidly and in a dose-dependent manner to exogenous auxin via proteasome-mediated degradation. Low levels of DII-specific fluorescence corresponding to high endogenous auxin signaling occurred near vasculature tissue and the outer layer and glume primordia of spikelet pair meristems and floral meristems, respectively. In addition, high DII levels were observed in cells during telophase and early G1, suggesting that low auxin signaling at these stages may be important for cell cycle progression.

Trigeminal Cephalgias and Facial Pain Syndromes Associated with Autonomic Dysfunction

Trigeminal autonomic cephalgias (TACs) include a spectrum of primary headache syndromes associated with cranial autonomic dysfunction. Other types of headache and facial pain syndromes can be associated with marked localized facial or ear autonomic changes. We report on a group of patients suffering from episodic migraine with cranial autonomic features, patients with different presentations of the ‘red ear syndrome’ (RES), cluster headache with prominent lower facial involvement and crossover cases. In our experience crossover between TACs and migraine, RES and cluster headache is not uncommon. We propose that all these conditions belong to the same group and a unifying causative mechanism is proposed.