The involvement of ethylene in fruit ripening is well documented, though knowledge regarding the crosstalk between ethylene and other hormones in ripening is lacking. We discovered that AUXIN ...RESPONSE FACTOR 2A (ARF2A), a recognized auxin signaling component, functions in the control of ripening. ARF2A expression is ripening regulated and reduced in the rin, nor and nr ripening mutants. It is also responsive to exogenous application of ethylene, auxin and abscisic acid (ABA). Over-expressing ARF2A in tomato resulted in blotchy ripening in which certain fruit regions turn red and possess accelerated ripening. ARF2A over-expressing fruit displayed early ethylene emission and ethylene signaling inhibition delayed their ripening phenotype, suggesting ethylene dependency. Both green and red fruit regions showed the induction of ethylene signaling components and master regulators of ripening. Comprehensive hormone profiling revealed that altered ARF2A expression in fruit significantly modified abscisates, cytokinins and salicylic acid while gibberellic acid and auxin metabolites were unaffected. Silencing of ARF2A further validated these observations as reducing ARF2A expression let to retarded fruit ripening, parthenocarpy and a disturbed hormonal profile. Finally, we show that ARF2A both homodimerizes and interacts with the ABA STRESS RIPENING (ASR1) protein, suggesting that ASR1 might be linking ABA and ethylene-dependent ripening. These results revealed that ARF2A interconnects signals of ethylene and additional hormones to co-ordinate the capacity of fruit tissue to initiate the complex ripening process.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Chemical and transgenic approaches can activate ABA signalling via crop PYR/PYL ABA receptors; quinabactin can selectively activate tomato ABA receptors, and overexpression of monomeric-type ...receptors confers enhanced plant drought resistance.
All-flesh tomato cultivars are devoid of locular gel and exhibit enhanced firmness and improved postharvest storage. Here, we show that SlMBP3 is a master regulator of locular tissue in tomato fruit ...and that a deletion at the gene locus underpins the All-flesh trait. Intriguingly, All-flesh varieties lack the deleterious phenotypes reported previously for SlMBP3 under-expressing lines and which preclude any potential commercial use. We resolve the causal factor for this phenotypic divergence through the discovery of a natural mutation at the SlAGL11 locus, a close homolog of SlMBP3. Misexpressing SlMBP3 impairs locular gel formation through massive transcriptomic reprogramming at initial phases of fruit development. SlMBP3 influences locule gel formation by controlling cell cycle and cell expansion genes, indicating that important components of fruit softening are determined at early pre-ripening stages. Our findings define potential breeding targets for improved texture in tomato and possibly other fleshy fruits.
Cold storage induces chilling injury (CI) disorders in peach fruit (woolliness/mealiness, flesh browning and reddening/bleeding) manifested when ripened at shelf life. To gain insight into the ...mechanisms underlying CI, we analyzed the transcriptome of 'Oded' (high tolerant) and 'Hermoza' (relatively tolerant to woolliness, but sensitive to browning and bleeding) peach cultivars at pre-symptomatic stages. The expression profiles were compared and validated with two previously analyzed pools (high and low sensitive to woolliness) from the Pop-DG population. The four fruit types cover a wide range of sensitivity to CI. The four fruit types were also investigated with the ROSMETER that provides information on the specificity of the transcriptomic response to oxidative stress.
We identified quantitative differences in a subset of core cold responsive genes that correlated with sensitivity or tolerance to CI at harvest and during cold storage, and also subsets of genes correlating specifically with high sensitivity to woolliness and browning. Functional analysis indicated that elevated levels, at harvest and during cold storage, of genes related to antioxidant systems and the biosynthesis of metabolites with antioxidant activity correlates with tolerance. Consistent with these results, ROSMETER analysis revealed oxidative stress in 'Hermoza' and the progeny pools, but not in the cold resistant 'Oded'. By contrast, cold storage induced, in sensitivity to woolliness dependant manner, a gene expression program involving the biosynthesis of secondary cell wall and pectins. Furthermore, our results indicated that while ethylene is related to CI tolerance, differential auxin subcellular accumulation and signaling may play a role in determining chilling sensitivity/tolerance. In addition, sugar partitioning and demand during cold storage may also play a role in the tolerance/sensitive mechanism. The analysis also indicates that vesicle trafficking, membrane dynamics and cytoskeleton organization could have a role in the tolerance/sensitive mechanism. In the case of browning, our results suggest that elevated acetaldehyde related genes together with the core cold responses may increase sensitivity to browning in shelf life.
Our data suggest that in sensitive fruit a cold response program is activated and regulated by auxin distribution and ethylene and these hormones have a role in sensitivity to CI even before fruit are cold stored.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Introduction
Pregnant women have an increased risk of severe COVID‐19. Evaluation of drugs with a safety reproductive toxicity profile is a priority. At the beginning of the pandemic, ...hydroxychloroquine (HCQ) was recommended for COVID‐19 treatment.
Material and methods
A randomized, double‐blind, placebo‐controlled clinical trial was conducted in eight teaching hospitals in Spain to evaluate the safety and efficacy of HCQ in reducing viral shedding and preventing COVID‐19 progression. Pregnant and postpartum women with a positive SARS‐CoV‐2 PCR (with or without mild COVID‐19 signs/symptoms) and a normal electrocardiogram were randomized to receive either HCQ orally (400 mg/day for 3 days and 200 mg/day for 11 days) or placebo. PCR and electrocardiogram were repeated at day 21 after treatment start. Enrollment was stopped before reaching the target sample due to low recruitment rate. Trial registration EudraCT #: 2020‐001587‐29, on April 2, 2020. Clinical trials.gov # NCT04410562, registered on June 1, 2020.
Results
A total of 116 women (75 pregnant and 41 post‐partum) were enrolled from May 2020 to June 2021. The proportion of women with a positive SARS‐CoV‐2 PCR at day 21 was lower in the HCQ group (21.8%, 12/55) than in the placebo group (31.6%, 18/57), although the difference was not statistically significant (P = 0.499). No differences were observed in COVID‐19 progression, adverse events, median change in QTc, hospital admissions, preeclampsia or poor pregnancy and perinatal outcomes between groups.
Conclusions
HCQ was found to be safe in pregnant and postpartum women with asymptomatic or mild SARS‐CoV‐2 infection. Although the prevalence of infection was decreased in the HCQ group, the statistical power was insufficient to confirm the potential beneficial effect of HCQ for COVID‐19 treatment.
This study is the only completed clinical trial evaluating a drug for COVID‐19 among pregnant women. Prevalence of infection was decreased in the HCQ group, but low recruitment led to insufficient statistical power to confirm the potential beneficial effect of HCQ.
The World Health Organization recommends intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine for malaria for all women who live in moderate to high malaria ...transmission areas in Africa. However, parasite resistance to sulfadoxine-pyrimethamine has been increasing steadily in some areas of the region. Moreover, HIV-infected women on cotrimoxazole prophylaxis cannot receive sulfadoxine-pyrimethamine because of potential drug interactions. Thus, there is an urgent need to identify alternative drugs for prevention of malaria in pregnancy. One such candidate is mefloquine.
To assess the effects of mefloquine for preventing malaria in pregnant women, specifically, to evaluate:• the efficacy, safety, and tolerability of mefloquine for preventing malaria in pregnant women; and• the impact of HIV status, gravidity, and use of insecticide-treated nets on the effects of mefloquine.
We searched the Cochrane Infectious Diseases Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE, Embase, Latin American Caribbean Health Sciences Literature (LILACS), the Malaria in Pregnancy Library, and two trial registers up to 31 January 2018. In addition, we checked references and contacted study authors to identify additional studies, unpublished data, confidential reports, and raw data from published trials.
Randomized and quasi-randomized controlled trials comparing mefloquine IPT or mefloquine prophylaxis against placebo, no treatment, or an alternative drug regimen.
Two review authors independently screened all records identified by the search strategy, applied inclusion criteria, assessed risk of bias, and extracted data. We contacted trial authors to ask for additional information when required. Dichotomous outcomes were compared using risk ratios (RRs), count outcomes as incidence rate ratios (IRRs), and continuous outcomes using mean differences (MDs). We have presented all measures of effect with 95% confidence intervals (CIs). We assessed the certainty of evidence using the GRADE approach for the following main outcomes of analysis: maternal peripheral parasitaemia at delivery, clinical malaria episodes during pregnancy, placental malaria, maternal anaemia at delivery, low birth weight, spontaneous abortions and stillbirths, dizziness, and vomiting.
Six trials conducted between 1987 and 2013 from Thailand (1), Benin (3), Gabon (1), Tanzania (1), Mozambique (2), and Kenya (1) that included 8192 pregnant women met our inclusion criteria.Two trials (with 6350 HIV-uninfected pregnant women) compared two IPTp doses of mefloquine with two IPTp doses of sulfadoxine-pyrimethamine. Two other trials involving 1363 HIV-infected women compared three IPTp doses of mefloquine plus cotrimoxazole with cotrimoxazole. One trial in 140 HIV-infected women compared three doses of IPTp-mefloquine with cotrimoxazole. Finally, one trial enrolling 339 of unknown HIV status compared mefloquine prophylaxis with placebo.Study participants included women of all gravidities and of all ages (four trials) or > 18 years (two trials). Gestational age at recruitment was > 20 weeks (one trial), between 16 and 28 weeks (three trials), or ≤ 28 weeks (two trials). Two of the six trials blinded participants and personnel, and only one had low risk of detection bias for safety outcomes.When compared with sulfadoxine-pyrimethamine, IPTp-mefloquine results in a 35% reduction in maternal peripheral parasitaemia at delivery (RR 0.65, 95% CI 0.48 to 0.86; 5455 participants, 2 studies; high-certainty evidence) but may have little or no effect on placental malaria infections (RR 1.04, 95% CI 0.58 to 1.86; 4668 participants, 2 studies; low-certainty evidence). Mefloquine results in little or no difference in the incidence of clinical malaria episodes during pregnancy (incidence rate ratio (IRR) 0.83, 95% CI 0.65 to 1.05, 2 studies; high-certainty evidence). Mefloquine decreased maternal anaemia at delivery (RR 0.84, 95% CI 0.76 to 0.94; 5469 participants, 2 studies; moderate-certainty evidence). Data show little or no difference in the proportions of low birth weight infants (RR 0.95, 95% CI 0.78 to 1.17; 5641 participants, 2 studies; high-certainty evidence) and in stillbirth and spontaneous abortion rates (RR 1.20, 95% CI 0.91 to 1.58; 6219 participants, 2 studies; I
statistic = 0%; high-certainty evidence). IPTp-mefloquine increased drug-related vomiting (RR 4.76, 95% CI 4.13 to 5.49; 6272 participants, 2 studies; high-certainty evidence) and dizziness (RR 4.21, 95% CI 3.36 to 5.27; participants = 6272, 2 studies; high-certainty evidence).When compared with cotrimoxazole, IPTp-mefloquine plus cotrimoxazole probably results in a 48% reduction in maternal peripheral parasitaemia at delivery (RR 0.52, 95% CI 0.30 to 0.93; 989 participants, 2 studies; moderate-certainty evidence) and a 72% reduction in placental malaria (RR 0.28, 95% CI 0.14 to 0.57; 977 participants, 2 studies; high-certainty evidence) but has little or no effect on the incidence of clinical malaria episodes during pregnancy (IRR 0.76, 95% CI 0.33 to 1.76, 1 study; high-certainty evidence) and probably no effect on maternal anaemia at delivery (RR 0.94, 95% CI 0.73 to 1.20; 1197 participants, 2 studies; moderate-certainty evidence), low birth weight rates (RR 1.20, 95% CI 0.89 to 1.60; 1220 participants, 2 studies; moderate-certainty evidence), and rates of spontaneous abortion and stillbirth (RR 1.12, 95% CI 0.42 to 2.98; 1347 participants, 2 studies; very low-certainty evidence). Mefloquine was associated with higher risks of drug-related vomiting (RR 7.95, 95% CI 4.79 to 13.18; 1055 participants, one study; high-certainty evidence) and dizziness (RR 3.94, 95% CI 2.85 to 5.46; 1055 participants, 1 study; high-certainty evidence).
Mefloquine was more efficacious than sulfadoxine-pyrimethamine in HIV-uninfected women or daily cotrimoxazole prophylaxis in HIV-infected pregnant women for prevention of malaria infection and was associated with lower risk of maternal anaemia, no adverse effects on pregnancy outcomes (such as stillbirths and abortions), and no effects on low birth weight and prematurity. However, the high proportion of mefloquine-related adverse events constitutes an important barrier to its effectiveness for malaria preventive treatment in pregnant women.
Fruit of tomato (Solarium lycopersicum), like those from many species, have been characterized to undergo a shift from partially photosynthetic to truly heterotrophic metabolism. While there is ...plentiful evidence for functional photosynthesis in young tomato fruit, the rates of carbon assimilation rarely exceed those of carbon dioxide release, raising the question of its role in this tissue. Here, we describe the generation and characterization of lines exhibiting a fruit-specific reduction in the expression of glutamate 1-semialdehyde aminotransferase (GSA). Despite the fact that these plants contained less GSA protein and lowered chlorophyll levels and photosynthetic activity, they were characterized by few other differences. Indeed, they displayed almost no differences in fruit size, weight, or ripening capacity and furthermore displayed few alterations in other primary or intermediary metabolites. Although GSA antisense lines were characterized by significant alterations in the expression of genes associated with photosynthesis, as well as with cell wall and amino acid metabolism, these changes were not manifested at the phenotypic level. One striking feature of the antisense plants was their seed phenotype: the transformants displayed a reduced seed set and altered morphology and metabolism at early stages of fruit development, although these differences did not affect the final seed number or fecundity. Taken together, these results suggest that fruit photosynthesis is, at least under ambient conditions, not necessary for fruit energy metabolism or development but is essential for properly timed seed development and therefore may confer an advantage under conditions of stress.
Introduction
Tomato is a high economic value crop worldwide with recognized nutritional properties and diverse postharvest potential. Nowadays, there is an emerging awareness about the exploitation ...and utilization of underutilized traditional germplasm in modern breeding programs. In this context, the existing diversity among Greek accessions in terms of their postharvest life and nutritional value remains largely unexplored.
Methods
Herein, a detailed evaluation of 130 tomato Greek accessions for postharvest and nutritional characteristics was performed, using metabolomics and transcriptomics, leading to the selection of accessions with these interesting traits.
Results
The results showed remarkable differences among tomato Greek accessions for overall ripening parameters (color, firmness) and weight loss. On the basis of their postharvest performance, a balance between short shelf life (SSL) and long shelf life (LSL) accessions was revealed. Metabolome analysis performed on 14 selected accessions with contrasting shelf-life potential identified a total of 206 phytonutrients and volatile compounds. In turn, transcriptome analysis in fruits from the best SSL and the best LSL accessions revealed remarkable differences in the expression profiles of transcripts involved in key metabolic pathways related to fruit quality and postharvest potential.
Discussion
The pathways towards cell wall synthesis, polyamine synthesis, ABA catabolism, and steroidal alkaloids synthesis were mostly induced in the LSL accession, whereas those related to ethylene biosynthesis, cell wall degradation, isoprenoids, phenylpropanoids, ascorbic acid and aroma (
TomloxC
) were stimulated in the SSL accession. Overall, these data would provide valuable insights into the molecular mechanism towards enhancing shelf-life and improving flavor and aroma of modern tomato cultivars.
The individual effects of biotic and abiotic factors on tomatoes have been widely reported. However, under commercial conditions, multiple interactions between factors occur, masking or even changing ...the direction of their effects in some cases. Here we report a comprehensive analysis of preharvest factors affecting yield, quality (soluble solids content, fruit color, and firmness), and shelf-life of long-shelf-life Mediterranean varieties of tomatoes. We studied five long-shelf-life genotypes under 16 growing environments, including tunnel and open-air systems and suboptimal to excessive fertigation (22–142% crop evapotranspiration). The results enabled us to classify traits into three groups according to the importance of the contributions of different types of factors: mainly genotype (ripening earliness and firmness), genotype plus environment (yield, fruit weight, water-use efficiency (WUE)), or genotype plus environment plus the interaction between genotype and environment (cracking, soluble solids content, and shelf-life). Under similar management practices, open-air conditions optimized yields, and high fertigation doses improved yield and marketability (firmness), but reduced quality (redness and soluble solids content). WUE was maximized under low-input cropping systems (comparable to traditional agrosystems), and the balance between WUE and yield was optimized when fertigation was adjusted to the requirements of the crop. Shelf-life was negatively correlated with high-yielding environments, and day–night amplitude in relative humidity was strongly correlated with the incidence of fruit cracking. The present study sheds light on the contributions of environment and management practices on tomato yield and quality, and provides a basis on which to select better management practices for the novel commercial group of European long-shelf-life tomato landraces.
Objectives
To analyse the association between socio‐economic status (SES) and HIV in Manhiça, a district of Southern Mozambique with one of the highest HIV prevalences in the world.
Methods
Data were ...gathered from two cross‐sectional surveys performed in 2010 and 2012 among 1511 adults and from the household census of the district's population. Fractional polynomial logit models were used to analyse the association between HIV and SES, controlling for age and sex and taking into account the nonlinearity of covariates. The inequality of the distribution of HIV infection with regard to SES was computed through a concentration index.
Results
Fourth and fifth wealth quintiles, the least poor, were associated with a reduced probability of HIV infection compared to the first quintile (OR = 0.595, P‐value = 0.009 and OR = 0.474, P‐value < 0.001, respectively). Probability of HIV infection peaked at 36 years and then fell, and was always higher for women regardless of age and SES. HIV infection was unequally distributed across the SES strata.
Conclusions
Despite the high HIV prevalence across the entire population of Manhiça, the poorest are at greatest risk of being HIV infected. While women have a higher probability of being HIV positive than men, both sexes showed the same infection reduction at higher levels of SES. HIV interventions in the area should particularly focus on the poorest and on women without neglecting anyone else, as the HIV risk is high for everyone.
Objectifs
Analyser l'association entre le statut socioéconomique (SSE) et le VIH à Manhiça, un district du Sud du Mozambique avec l'une des prévalences les plus élevées du VIH dans le monde.
Méthodes
Les données ont été recueillies à partir de deux enquêtes transversales réalisées en 2010 et 2012 chez 1511 adultes et à partir du recensement des ménages de la population du district. Les modèles logit fractionnaires polynômiaux ont été utilisés pour analyser l'association entre le VIH et le SSE, en ajustant pour l’âge et le sexe et en prenant en compte la non‐linéarité des covariables. L'inégalité de la distribution de l'infection VIH en ce qui concerne le SSE a été calculée selon un indice de concentration.
Résultats
Les quatrième et cinquième quintiles de richesse, les moins pauvres, ont été associés à une probabilité réduite de l'infection par le VIH, comparés au premier quintile (OR = 0,595; P = 0,009 et OR = 0,474; P <0,001, respectivement). La probabilité d'infection par le VIH a atteint un pic à 36 ans, puis est retombée et a toujours été plus élevée chez les femmes, quel que soit l’âge et le SSE. L'infection par le VIH était inégalement répartie entre les strates de SSE.
Conclusions
Malgré la prévalence élevée du VIH dans l'ensemble de la population de Manhiça, les plus pauvres sont les plus à risque d’être infectés par le VIH. Alors que les femmes ont une plus grande probabilité d’être VHI positives que les hommes, les deux genres ont montré la même réduction de l'infection pour des niveaux plus élevés de SSE. Les interventions contre le VIH dans la région devraient se concentrer notamment sur les plus pauvres et sur les femmes sans négliger les autres, car le risque du VIH est élevé pour tout le monde.
Objetivos
Analizar la asociación entre el estatus socioeconómico (ESE) y el VIH en Manhiça, un distrito en el sur de Mozambique con una de las prevalencias más altas a nivel mundial.
Métodos
Se recogieron datos de dos estudios croseccionales realizados en el 2010 y el 2012 entre 1511 adultos, y del censo realizado en los hogares del distrito. Se utilizaron modelos logit para analizar la asociación entre el VIH y el ESE, controlando por edad y sexo y teniendo en cuenta las covariables no lineales. La desigualdad en la distribución de la infección por VIH con respecto al ESE se tuvo en cuenta mediante un índice de concentración.
Resultados
El estar en el cuarto y quinto quintil de riqueza, entre los menos pobres, estaba asociado con un riesgo reducido de probabilidad de infección por VIH, comparado con el primer quintil (OR=0.595, P=0.009 y OR=0.474, P<0.001, respectivamente). La probabilidad de infección por VIH era mayor a los 36 años y después disminuía, y siempre era mayor para mujeres independientemente de la edad y el ESE. La infección por VIH estaba distribuida de forma desigual a lo largo del estrato ESE.
Conclusiones
A pesar de la alta prevalencia de VIH en toda la población de Manhiça, los más pobres tienen un mayor riesgo de estar infectados con VIH. Mientras las mujeres tienen una mayor probabilidad de ser VIH positivas que los hombres, ambos sexos presentan la misma reducción en el riesgo de infección con mayor nivel de ESE. Las intervenciones para el VIH realizadas en el área deberían centrarse en los más pobres y en las mujeres, sin desatender a los demás, puesto que el riesgo de VIH es alto para todos.
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