A newly identified ferritin L-subunit variant results in increased proteasomal subunit degradation, impaired complex assembly, and severe hypoferritinemia.

Ferritin is a hetero-oligomeric nanocage, composed of 24 subunits of two types, FTH1 and FTL. It protects the cell from excess reactive iron, by storing iron in its cavity. FTH1 is essential for the recruitment of iron into the ferritin nanocage and for cellular ferritin trafficking, whereas FTL contributes to nanocage stability and iron nucleation inside the cavity. Here we describe a female patient with a medical history of severe hypoferritinemia without anemia. Following inadequate heavy IV iron supplementation, the patient developed severe iron overload and musculoskeletal manifestations. However, her serum ferritin levels rose only to normal range. Genetic analyses revealed an undescribed homozygous variant of FTL (c.92A > G), which resulted in a Tyr31Cys substitution (FTLY31C ). Analysis of the FTL structure predicted that the Y31C mutation will reduce the variant's stability. Expression of the FTLY31C variant resulted in significantly lower cellular ferritin levels compared with the expression of wild-type FTL (FTLWT ). Proteasomal inhibition significantly increased the initial levels of FTLY31C , but could not protect FTLY31C subunits from successive degradation. Further, variant subunits successfully incorporated into hetero-polymeric nanocages in the presence of sufficient levels of FTH1. However, FTLY31C subunits poorly assembled into nanocages when FTH1 subunit levels were low. These results indicate an increased susceptibility of unassembled monomeric FTLY31C subunits to proteasomal degradation. The decreased cellular assembly of FTLY31C -rich nanocages may explain the low serum ferritin levels in this patient and emphasize the importance of a broader diagnostic approach of hypoferritinemia without anemia, before IV iron supplementation.

The different response of Brassica napus genotypes to microspore embryogenesis induced by heat shock and trichostatin A is not determined by changes in cell wall structure and composition but by different stress tolerance.

During microspore embryogenesis, microspores are induced to develop into haploid embryos. In Brassica napus, microspore embryogenesis is induced by a heat shock (HS), which initially produces embryogenic structures with different cell wall architectures and compositions, and with different potentials to develop into embryos. The B. napus DH4079 and DH12075 genotypes have high and very low embryo yields, respectively. In DH12075, embryo yield is greatly increased by combining HS and the histone deacetylase (HDAC) inhibitor trichostatin A (TSA). However, we show that HS + TSA inhibits embryogenesis in the highly embryogenic DH4079 line. To ascertain why TSA has such different effects in these lines, we treated DH4079 and DH12075 microspore cultures with TSA and compared the cell wall structure and composition of the different embryogenic structures in both lines, specifically the in situ levels and distribution of callose, cellulose, arabinogalactan proteins and high and low methyl-esterified pectin. For both lines, HS + TSA led to the formation of cell walls unfavorable for embryogenesis progression, with reduced levels of arabinogalactan proteins, reduced cell adhesion of inner walls and altered pectin composition. Thus, TSA effects on cell walls cannot explain their different embryogenic response to TSA. We also applied TSA to DH4079 cultures at different times and concentrations before HS application, with no negative effects on embryogenic induction. These results indicate that DH4079 microspores are hypersensitive to combined TSA and HS treatments, and open up new hypotheses about the causes of such hypersensitivity.

Exacerbated Activation of the NLRP3 Inflammasome in the Placentas from Women Who Developed Chronic Venous Disease during Pregnancy.

Chronic venous disease (CVD) comprises a spectrum of morphofunctional disorders affecting the venous system, affecting approximately 1 in 3 women during gestation. Emerging evidence highlights diverse maternofetal implications stemming from CVD, particularly impacting the placenta. While systemic inflammation has been associated with pregnancy-related CVD, preliminary findings suggest a potential link between this condition and exacerbated inflammation in the placental tissue. Inflammasomes are major orchestrators of immune responses and inflammation in different organs and systems. Notwithstanding the relevance of inflammasomes, specifically the NLRP3 (nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3)- which has been demonstrated in the placentas of women with different obstetric complications, the precise involvement of this component in the placentas of women with CVD remains to be explored. This study employs immunohistochemistry and real-time PCR (RT-qPCR) to examine the gene and protein expression of key components in both canonical and non-canonical pathways of the NLRP3 inflammasome (NLRP3, ASC-apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain-caspase 1, caspase 5, caspase 8, and interleukin 1ß) within the placental tissue of women affected by CVD. Our findings reveal a substantial upregulation of these components in CVD-affected placentas, indicating a potential pathophysiological role of the NLRP3 inflammasome in the development of this condition. Subsequent investigations should focus on assessing translational interventions addressing this dysregulation in affected patient populations.

Tenofovir Disoproxil Fumarate/Emtricitabine and Baricitinib for Patients at High Risk of Severe Coronavirus Disease 2019: The PANCOVID Randomized Clinical Trial.

BACKGROUND: This study was designed to evaluate if patients with high risk for severe coronavirus disease 2019 (COVID-19) would benefit from treatment with tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) followed by baricitinib in case of hypoxemia and systemic inflammation. METHODS: PANCOVID is an open-label, double-randomized, phase 3 pragmatic clinical trial including adults with symptomatic COVID-19 with ≥2 comorbidities or aged ≥60 years and was conducted between 10 October 2020 and 23 September 2021. In the first randomization, patients received TDF/FTC or no TDF/FTC. In the second randomization, patients with room air oxygen saturation <95% and at least 1 increased inflammatory biomarker received baricitinib plus dexamethasone or dexamethasone alone. The primary endpoint was 28-day mortality. Main secondary endpoint was 28-day disease progression or critical care unit admission or mortality. The trial was stopped before reaching planned sample size due to the decrease in the number of cases and a mortality rate substantially lower than expected. RESULTS: Of the 355 included participants, 97% were hospitalized at baseline. Overall, 28-day mortality was 3.1%. The 28-day mortality relative risk (RR) for participants treated with TDF/FTC was 1.76 (95% confidence interval [CI], .52-5.91; P = .379); it was 0.42 (95% CI, .11-1.59; P = .201) for those treated with baricitinib. The 28-day RR for the main secondary combined endpoint for participants treated with TDF/FTC was 0.95 (95% CI, .66-1.40; P = .774); it was 0.90 (95% CI, .61-1.33; P = .687) for those treated with baricitinib. CONCLUSIONS: Our results do not suggest a beneficial effect of TDF/FTC; nevertheless, they are compatible with the beneficial effect of baricitinib already established by other clinical trials. CLINICAL TRIALS REGISTRATION: EudraCT: 2020-001156-18.

Differential response of RTGUTGC and RTGILL-W1 rainbow trout epithelial cell lines to viral stimulation.

Mucosal surfaces constitute the main route of entry of pathogens into the host. In fish, these mucosal tissues include, among others, the gastrointestinal tract, the gills and the skin. However, knowledge about the mechanisms of regulation of immunity in these tissues is still scarce, being essential to generate a solid base that allows the development of prevention strategies against these infectious agents. In this work, we have used the RTgutGC and RTgill-W1 epithelial-like cell lines, derived from the gastrointestinal tract and the gill of rainbow trout (Oncorhynchus mykiss), respectively, to investigate the transcriptional response of mucosal epithelial cells to a viral mimic, the dsRNA poly I:C, as well as to two important viral rainbow trout pathogens, namely viral haemorrhagic septicaemia virus (VHSV) and infectious pancreatic necrosis virus (IPNV). Additionally, we have established how the exposure to poly I:C affected the susceptibility of RTgutGC and RTgill-W1 cells to both viruses. Our results reveal important differences in the way these two cell lines respond to viral stimuli, providing interesting information on these cell lines that have emerged in the past years as useful tools to study mucosal responses in fish.

Amyloid Precursor Protein (APP) Regulates Gliogenesis and Neurogenesis of Human Neural Stem Cells by Several Signaling Pathways.

Numerous studies have focused on the pathophysiological role of amyloid precursor protein (APP) because the proteolytic processing of APP to ß-amyloid (Aß) peptide is a central event in Alzheimer's disease (AD). However, many authors consider that alterations in the physiological functions of APP are likely to play a key role in AD. Previous studies in our laboratory revealed that APP plays an important role in the differentiation of human neural stem cells (hNSCs), favoring glial differentiation (gliogenesis) and preventing their differentiation toward a neuronal phenotype (neurogenesis). In the present study, we have evaluated the effects of APP overexpression in hNSCs at a global gene level by a transcriptomic analysis using the massive RNA sequencing (RNA-seq) technology. Specifically, we have focused on differentially expressed genes that are related to neuronal and glial differentiation processes, as well as on groups of differentially expressed genes associated with different signaling pathways, in order to find a possible interaction between them and APP. Our data indicate a differential expression in genes related to Notch, Wnt, PI3K-AKT, and JAK-STAT signaling, among others. Knowledge of APP biological functions, as well as the possible signaling pathways that could be related to this protein, are essential to advance our understanding of AD.

A simple clinical score to promote and enhance ferroportin disease screening.

BACKGROUND & AIMS: Ferroportin disease is a rare genetic iron overload disorder which may be underdiagnosed, with recent data suggesting it occurs at a higher prevalence than suspected. Costs and the lack of defined criteria to prompt genetic testing preclude large-scale molecular screening. Hence, we aimed to develop a readily available scoring system to promote and enhance ferroportin disease screening. METHODS: Our derivation cohort included probands tested for ferroportin disease from 2008 to 2016 in our rare disease network. Data were prospectively recorded. Univariate and multivariate logistic regression were used to determine significant criteria, and odds ratios were used to build a weighted score. A cut-off value was defined using a ROC curve with a predefined aim of 90% sensitivity. An independent cohort was used for cross validation. RESULTS: Our derivation cohort included 1,306 patients. Mean age was 55±14 years, ferritin 1,351±1,357 µg/L, and liver iron concentration (LIC) 166±77 µmol/g. Pathogenic variants (n = 32) were identified in 71 patients. In multivariate analysis: female sex, younger age, higher ferritin, higher LIC and the absence of hypertension or diabetes were significantly associated with the diagnosis of ferroportin disease (AUROC in whole derivation cohort 0.83 [0.78-0.88]). The weighted score was based on sex, age, the presence of hypertension or diabetes, ferritin level and LIC. An AUROC of 0.83 (0.77-0.88) was obtained in the derivation cohort without missing values. Using 9.5 as a cut-off, sensitivity was 93.6 (91.7-98.3) %, specificity 49.5 (45.5-53.6) %, positive likelihood ratio 1.8 (1.6-2.0) and negative likelihood ratio 0.17 (0.04-0.37). CONCLUSION: We describe a readily available score with simple criteria and good diagnostic performance that could be used to screen patients for ferroportin disease in routine clinical practice. LAY SUMMARY: Increased iron burden associated with metabolic syndrome is a very common condition. Ferroportin disease is a dominant genetic iron overload disorder whose prevalence is higher than initially thought. They can be difficult to distinguish from each other, but the limited availability of genetic testing and the lack of definitive guidelines prevent adequate screening. We herein describe a simple and definitive clinical score to help clinicians decide whether to perform genetic testing.

Incidence of type 1 diabetes in children in Dominican Republic, 2010-2019: A national collaborative study.

The Dominican Republic has no recent data on type 1 diabetes (T1D) incidence in children. Therefore, a study was undertaken to determine this in persons aged <15 years (y). Data were collected on all new T1D diagnoses between 2010-2019 from the four institutions caring for children with T1D. Diagnosis was made according to standard criteria. No secondary ascertainment source was available. The trend and the effect of age and sex of T1D incidence was analyzed using Poisson regression. A total of 1224 new cases of T1D were diagnosed <15 y; mean ± standard deviation (range) 122 ± 12 (96-135) cases per year. Age at T1D diagnosis was 8.8 ± 3.7 y, with a significant female preponderance (n = 708, 57.8%, p < 0.001). When examined per 5-y age group, cases were consistently highest in 10-14 y, and lowest in 0-4 y in all study years. Mean crude T1D annual incidence was 4.3 (95% CI 3.5-5.1) per 100,000 population. There was no significant difference between incidence across the country's three departments (regions): Southeast (4.4 [3.4-5.7]/100,000 population), North (4.1 [2.9-5.6]), and Southwest (3.9 [2.4-5.9]). Mean standardized annual incidence was 4.1 (4.1-4.2) per 100,000 population, with no significant trend of increase over the study period. The incidence of T1D in children aged <15 y is relatively low in Dominican Republic, but consistent with the limited data from other countries in the region. However, the incidence is eight times higher than the previous estimate during 1995-1999. Ongoing surveillance is warranted.

Hourly Analysis of Mechanical Ventilation Parameters in Critically Ill Adult Covid-19 Patients: Association with Mortality.

Objective: There exists controversy about the pathophysiology and lung mechanics of COVID-19 associated acute respiratory distress syndrome (ARDS), because some report severe hypoxemia with preserved respiratory system mechanics, contrasting with "classic" ARDS. We performed a detailed hourly analysis of the characteristics and time course of lung mechanics and biochemical analysis of patients requiring invasive mechanical ventilation (IMV) for COVID-19-associated ARDS, comparing survivors and non-survivors. Methods: Retrospective analysis of the data stored in the ICU information system of patients admitted in our hospital ICU that required IMV due to confirmed SARS-CoV-2 pneumonia between March 5th and April 30th, 2020. We compare respiratory system mechanics and gas exchange during the first ten days of IMV, discriminating volume and pressure controlled modes, between ICU survivors and non-survivors. Results: 140 patients were included, analyzing 11 138 respiratory mechanics recordings. Global mortality was 38.6%. Multivariate analysis showed that age (OR 1.092, 95% (CI 1.014-1.176)) and need of renal replacement therapies (OR 10.15, (95% CI 1.58-65.11)) were associated with higher mortality. Previous use of Angiotensin Converting Enzyme inhibitor (ACEI)/angiotensin-receptor blockers (ARBs) also seemed to show an increased mortality (OR 4.612, (95% CI 1.19-17.84)) although this significance was lost when stratifying by age. Respiratory variables start to diverge significantly between survivors and non-survivors after the 96 to 120 hours (hs) from mechanical ventilation initiation, particularly respiratory system compliance. In non survivors, mechanical power at 24 and 96 hs was higher regardless ventilatory mode. Conclusions: In patients admitted for SARS-CoV-2 pneumonia and requiring mechanical ventilation, non survivors have different respiratory system mechanics than survivors in the first 10 days of ICU admission. We propose a checkpoint at 96-120 hs to assess patients improvement or worsening in order to consider escalating to extracorporeal therapies.

Hetero-oligomerization of Bacillus thuringiensis Cry1A proteins enhance binding to the ABCC2 transporter of Spodoptera exigua.

The ATP binding cassette (ABC) transporters are membrane proteins that can act as putative receptors for Cry proteins from Bacillus thuringiensis (Bt) in the midgut of different insects. For the beet armyworm, Spodoptera exigua, ABCC2 and ABCC3 have been found to interact with Cry1A proteins, the main insecticidal proteins used in Bt crops, as well as Bt-based pesticides. The ABCC2 has shown to have specific binding towards Cry1Ac and is involved in the toxic process of Cry1A proteins, but the role of this transporter and how it relates with the Cry1A proteins is still unknown. Here, we have characterized the interactions between the SeABCC2 and the main proteins that bind to the receptor. By labeling the Cry1Aa protein, we have found that virtually all of the binding is in an oligomeric state, a conformation that allowed higher levels of specific binding that could not be achieved by the monomeric protein on its own. Furthermore, we have observed that Cry1A proteins can hetero-oligomerize in the presence of the transporter, which is reflected in an increase in binding and toxicity to SeABCC2-expressing cells. This synergism can be one of the reasons why B. thuringiensis co-expresses different Cry1 proteins that can apparently have similar binding preferences. The results from in vitro competition and ex vivo competition showed that Cry1Aa, Cry1Ab and Cry1Ac share functional binding sites. By using Cry1Ab-Cry1Ac chimeras, the presence of domain I from Cry1A proteins was revealed to be critical for oligomer formation.

Towards the Search for Potential Biomarkers in Osteosarcoma: State-of-the-Art and Translational Expectations.

Osteosarcoma represents a rare cause of cancer in the general population, accounting for <1% of malignant neoplasms globally. Nonetheless, it represents the main cause of malignant bone neoplasm in children, adolescents and young adults under 20 years of age. It also presents another peak of incidence in people over 50 years of age and is associated with rheumatic diseases. Numerous environmental risk factors, such as bone diseases, genetics and a history of previous neoplasms, have been widely described in the literature, which allows monitoring a certain group of patients. Diagnosis requires numerous imaging tests that make it possible to stratify both the local involvement of the disease and its distant spread, which ominously determines the prognosis. Thanks to various clinical trials, the usefulness of different chemotherapy regimens, radiotherapy and surgical techniques with radical intent has now been demonstrated; these represent improvements in both prognosis and therapeutic approaches. Osteosarcoma patients should be evaluated in reference centres by multidisciplinary committees with extensive experience in proper management. Although numerous genetic and rheumatological diseases and risk factors have been described, the use of serological, genetic or other biomarkers has been limited in clinical practice compared to other neoplasms. This limits both the initial follow-up of these patients and screening in populations at risk. In addition, we cannot forget that the diagnosis is mainly based on the direct biopsy of the lesion and imaging tests, which illustrates the need to study new diagnostic alternatives. Therefore, the purpose of this study is to review the natural history of the disease and describe the main biomarkers, explaining their clinical uses, prognosis and limitations.

Critical Domains in the Specific Binding of Radiolabeled Vip3Af Insecticidal Protein to Brush Border Membrane Vesicles from Spodoptera spp. and Cultured Insect Cells.

Vegetative insecticidal proteins (Vip3) from Bacillus thuringiensis have been used, in combination with Cry proteins, to better control insect pests and as a strategy to delay the evolution of resistance to Cry proteins in Bt crops (crops protected from insect attack by the expression of proteins from B. thuringiensis). In this study, we have set up the conditions to analyze the specific binding of 125I-Vip3Af to Spodoptera frugiperda and Spodoptera exigua brush border membrane vesicles (BBMV). Heterologous competition binding experiments revealed that Vip3Aa shares the same binding sites with Vip3Af, but Vip3Ca does not recognize all of them. As expected, Cry1Ac and Cry1F did not compete for Vip3Af binding sites. By trypsin treatment of selected alanine mutants, we were able to generate truncated versions of Vip3Af. Their use as competitors with 125I-Vip3Af indicated that only those molecules containing domains I to III (DI-III and DI-IV) were able to compete with the trypsin-activated Vip3Af protein for binding and that molecules only containing either domain IV or domains IV and V (DIV and DIV-V) were unable to compete with Vip3Af. These results were further confirmed with competition binding experiments using 125I-DI-III. In addition, the truncated protein 125I-DI-III also bound specifically to Sf21 cells. Cell viability assays showed that the truncated proteins DI-III and DI-IV were as toxic to Sf21 cells as the activated Vip3Af, suggesting that domains IV and V are not necessary for the toxicity to Sf21 cells, in contrast to their requirement in vivo.IMPORTANCE This study shows that Vip3Af binding sites are fully shared with Vip3Aa, only partially shared with Vip3Ca, and not shared with Cry1Ac and Cry1F in two Spodoptera spp. Truncated versions of Vip3Af revealed that only domains I to III were necessary for the specific binding, most likely because they can form the functional tetrameric oligomer and because domain III is supposed to contain the binding epitopes. In contrast to results obtained in vivo (bioassays against larvae), domains IV and V are not necessary for ex vivo toxicity to Sf21 cells.

Effect of substitutions of key residues on the stability and the insecticidal activity of Vip3Af from Bacillus thuringiensis.

Modern agriculture demands for more sustainable agrochemicals to reduce the environmental and health impact. The whole process of the discovery and development of new active substances or control agents is sorely slow and expensive. Vegetative insecticidal proteins (Vip3) from Bacillus thuringiensis are specific toxins against caterpillars with a potential capacity to broaden the range of target pests. Site-directed mutagenesis is one of the most approaches used to test hypotheses on the role of different amino acids on the structure and function of proteins. To gain a better understanding of the role of key amino acid residues of Vip3A proteins, we have generated 12 mutants of the Vip3Af1 protein by site-directed mutagenesis, distributed along the five structural domains of the protein. Ten of these mutants were successfully expressed and tested for stability and toxicity against three insect pests (Spodoptera frugiperda, Spodoptera littoralis and Grapholita molesta). The results showed that, to render a wild type fragment pattern upon trypsin treatment, position 483 required an acidic residue, and position 552 an aromatic residue. Regarding toxicity, the change of Met34 to Lys34 significantly increased the toxicity of the protein for one of the three insect species tested (S. littoralis), whereas the other residue substitutions did not improve, or even decreased, insect toxicity, confirming their key role in the structure/function of the protein.

A structural analysis of 2,5-diaryl-4H-2,4-dihydro-3H-1,2,4-triazol-3-ones: NMR in the solid state, X-ray crystallography, and GIPAW calculations.

The 1 H, 13 C, 15 N, and 19 F nuclear magnetic resonance (NMR) spectra of 11 2,5-diaryl-2,4-dihydro-3H-1,2,4-triazol-3-ones have been acquired in DMSO-d6 solution and the 13 C, 15 N, and 19 F NMR spectra have also been acquired in the solid state (solid-state nuclear magnetic resonance [SSNMR] and magic angle spinning [MAS]). The X-ray structures of Compounds 3, 5, and 6 have been determined by X-ray diffraction. Theoretical calculations at the gauge-independent atomic orbital (GIAO)/B3LYP/6-311++G(d,p) level have provided a set of 321 chemical shifts that were compared with 310 experimental values in DMSO-d6 . To obtain good agreements, some effects need to be included. The SSNMR chemical shifts have been compared with gauge-including projector-augmented wave (GIPAW) calculations and with the heavy atom-light atom (HALA) effects.

Growth of a bubble cloud in CO2-saturated water under microgravity.

The diffusion-driven growth of a dense cloud of bubbles immersed in a gas-supersaturated liquid is a problem that finds applications in several modern technologies such as solvent-exchange micro-reactors, nanotechnology or the manufacturing of foamy materials. However, under Earth's gravity conditions, these dynamics can only be observed for a very limited time if the cloud is not attached to a surface, due to the action of buoyancy, i.e. of gravity effects. Here, we present experimental observations of the time evolution of dense bubble clouds growing in CO2-supersaturated water under microgravity conditions. We report the existence of three regimes where the bubble cloud exhibits different growth rates. At short times, each bubble grows independently following the Epstein-Plesset equation. Later on, bubbles start to interact with each other and their growth rate diminishes as they compete for the available CO2. When this happens, the growth rate slows down. This occurs earlier the deeper the bubble is in the cloud. Finally, at long times, only those bubbles on the husk continue growing. These regimes may be qualitatively described by a mathematical model where each individual bubble grows in the presence of a constellation of point mass sinks. Despite the model being only valid for dilute bubble clouds, its predictions are consistent with the experimental observations, even though the bubble clouds we observe are rather dense.

HLA-A*32:01 is strongly associated with vancomycin-induced drug reaction with eosinophilia and systemic symptoms.

BACKGROUND: Vancomycin is a prevalent cause of the severe hypersensitivity syndrome drug reaction with eosinophilia and systemic symptoms (DRESS), which leads to significant morbidity and mortality and commonly occurs in the setting of combination antibiotic therapy, affecting future treatment choices. Variations in HLA class I in particular have been associated with serious T cell-mediated adverse drug reactions, which has led to preventive screening strategies for some drugs. OBJECTIVE: We sought to determine whether variation in the HLA region is associated with vancomycin-induced DRESS. METHODS: Probable vancomycin-induced DRESS cases were matched 1:2 with tolerant control subjects based on sex, race, and age by using BioVU, Vanderbilt's deidentified electronic health record database. Associations between DRESS and carriage of HLA class I and II alleles were assessed by means of conditional logistic regression. An extended sample set from BioVU was used to conduct a time-to-event analysis of those exposed to vancomycin with and without the identified HLA risk allele. RESULTS: Twenty-three subjects met the inclusion criteria for vancomycin-associated DRESS. Nineteen (82.6%) of 23 cases carried HLA-A*32:01 compared with 0 (0%) of 46 of the matched vancomycin-tolerant control subjects (P = 1 × 10-8) and 6.3% of the BioVU population (n = 54,249, P = 2 × 10-16). Time-to-event analysis of DRESS development during vancomycin treatment among the HLA-A*32:01-positive group indicated that 19.2% had DRESS and did so within 4 weeks. CONCLUSIONS: HLA-A*32:01 is strongly associated with vancomycin-induced DRESS in a population of predominantly European ancestry. HLA-A*32:01 testing could improve antibiotic safety, help implicate vancomycin as the causal drug, and preserve future treatment options with coadministered antibiotics.

The Importance of Characterizing the Hemoglobin Instability of New Variants: The Case of Hb Dompierre [ß29(B11)Gly→Arg, HBB: c.88G>C].

Hb Dompierre [ß29(B11)Gly→Arg, HBB: c.88G>C] is a rare ß-globin gene variant that was previously described in the heterozygous state in a 24-year-old female patient. It is defined in the HbVar database as being clinically and biologically asymptomatic. A few years after the first description, we had an opportunity of reassessing the index case because she presented with splenomegaly and clinical and biological manifestations of hemolysis. After ruling out the most common causes of hemolysis, further analyses on the variant hemoglobin (Hb) using brilliant cresyl blue staining, indicated that it showed mild instability, which may explain the clinical and biological manifestations. A structural bioinformatic analysis on the Hb variant suggested that the amino acid replacement may be deleterious to the integrity of the Hb. This report confirms the importance of completely characterizing all new Hb variants in order to guide the patients' clinical management and follow-up, as well as to provide the probands and their family members with appropriate genetic counseling.

Gastrointestinal infection with Aeromonas: incidence and relationship to inflammatory bowel disease. / Infección gastrointestinal por Aeromonas: incidencia y su posible relación con la enfermedad inflamatoria intestinal.

INTRODUCTION: Aeromonas can cause several diseases in humans, with gastroenteritis accounting for most cases. The role of Aeromonas as a pathogen in human enterocolitis has been questioned in recent years. OBJECTIVE: To determine the incidence of gastrointestinal infection caused by Aeromonas in our area and its possible relationship to inflammatory bowel disease. PATIENTS AND METHODS: This was a retrospective observational study. All adult patients with a positive stool culture for Aeromonas were identified between January 2015 and December 2017 at Hospital Galdakao-Usansolo (Vizcaya, Spain). RESULTS: Ninety-eight patients were identified (median age 62 years; 51% women). Therefore, the incidence in our area was 32 cases per 105 inhabitants per year. Eleven per cent of them had been previously diagnosed with inflammatory bowel disease (four with ulcerative colitis and seven with Crohn's disease). Patients with inflammatory bowel disease more often received immunosuppressive therapy. Conversely, patients without inflammatory bowel disease suffered from more comorbidities. We also found comorbidity to be the risk factor most associated with Aeromonas infection. CONCLUSION: Aeromonas infection is a common gastrointestinal infection that may occur in both immunocompetent and immunocompromised patients. Immunosuppression is a significant factor in inflammatory bowel disease patients, while comorbidity seems to confer a higher risk on patients without this disease.

Embryogenic competence of microspores is associated with their ability to form a callosic, osmoprotective subintinal layer.

Microspore embryogenesis is an experimental morphogenic pathway with important applications in basic research and applied plant breeding, but its genetic, cellular, and molecular bases are poorly understood. We applied a multidisciplinary approach using confocal and electron microscopy, detection of Ca2+, callose, and cellulose, treatments with caffeine, digitonin, and endosidin7, morphometry, qPCR, osmometry, and viability assays in order to study the dynamics of cell wall formation during embryogenesis induction in a high-response rapeseed (Brassica napus) line and two recalcitrant rapeseed and eggplant (Solanum melongena) lines. Formation of a callose-rich subintinal layer (SL) was common to microspore embryogenesis in the different genotypes. However, this process was directly related to embryogenic response, being greater in high-response genotypes. A link could be established between Ca2+ influx, abnormal callose/cellulose deposition, and the genotype-specific embryogenic competence. Callose deposition in inner walls and SLs are independent processes, regulated by different callose synthases. Viability and control of internal osmolality are also related to SL formation. In summary, we identified one of the causes of recalcitrance to embryogenesis induction: a reduced or absent protective SL. In responding genotypes, SLs are markers for changes in cell fate and serve as osmoprotective barriers to increase viability in imbalanced in vitro environments. Genotype-specific differences relate to different responses against abiotic (heat/osmotic) stresses.

Clinical and biological features in PIEZO1-hereditary xerocytosis and Gardos channelopathy: a retrospective series of 126 patients.

We describe the clinical, hematologic and genetic characteristics of a retrospective series of 126 subjects from 64 families with hereditary xerocytosis. Twelve patients from six families carried a KCNN4 mutation, five had the recurrent p.Arg352His mutation and one had a new deletion at the exon 7-intron 7 junction. Forty-nine families carried a PIEZO1 mutation, which was a known recurrent mutation in only one-third of the cases and private sequence variation in others; 12 new probably pathogenic missense mutations were identified. The two dominant features leading to diagnosis were hemolysis that persisted after splenectomy and hyperferritinemia, with an inconstant correlation with liver iron content assessed by magnetic resonance imaging. PIEZO1-hereditary xerocytosis was characterized by compensated hemolysis in most cases, perinatal edema of heterogeneous severity in more than 20% of families and a major risk of post-splenectomy thrombotic events, including a high frequency of portal thrombosis. In KCNN4-related disease, the main symptoms were more severe anemia, hemolysis and iron overload, with no clear sign of red cell dehydration; therefore, this disorder would be better described as a 'Gardos channelopathy'. These data on the largest series to date indicate that PIEZO1-hereditary xerocytosis and Gardos channelopathy are not the same disease although they share hemolysis, a high rate of iron overload and inefficient splenectomy. They demonstrate the high variability in clinical expression as well as genetic bases of PIEZO1-hereditary xerocytosis. These results will help to improve the diagnosis of hereditary xerocytosis and to provide recommendations on the clinical management in terms of splenectomy, iron overload and pregnancy follow-up.