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BACKGROUND: On tropical regions, phosphorus (P) fixation onto aluminum and iron oxides in soil clays restricts P diffusion from the soil to the root surface, limiting crop yields. While increased root surface area favors P uptake under low-P availability, the relationship between the three-dimensional arrangement of the root system and P efficiency remains elusive. Here, we simultaneously assessed allelic effects of loci associated with a variety of root and P efficiency traits, in addition to grain yield under low-P availability, using multi-trait genome-wide association. We also set out to establish the relationship between root architectural traits assessed in hydroponics and in a low-P soil. Our goal was to better understand the influence of root morphology and architecture in sorghum performance under low-P availability. RESULT: In general, the same alleles of associated SNPs increased root and P efficiency traits including grain yield in a low-P soil. We found that sorghum P efficiency relies on pleiotropic loci affecting root traits, which enhance grain yield under low-P availability. Root systems with enhanced surface area stemming from lateral root proliferation mostly up to 40 cm soil depth are important for sorghum adaptation to low-P soils, indicating that differences in root morphology leading to enhanced P uptake occur exactly in the soil layer where P is found at the highest concentration. CONCLUSION: Integrated QTLs detected in different mapping populations now provide a comprehensive molecular genetic framework for P efficiency studies in sorghum. This indicated extensive conservation of P efficiency QTL across populations and emphasized the terminal portion of chromosome 3 as an important region for P efficiency in sorghum. Increases in root surface area via enhancement of lateral root development is a relevant trait for sorghum low-P soil adaptation, impacting the overall architecture of the sorghum root system. In turn, particularly concerning the critical trait for water and nutrient uptake, root surface area, root system development in deeper soil layers does not occur at the expense of shallow rooting, which may be a key reason leading to the distinctive sorghum adaptation to tropical soils with multiple abiotic stresses including low P availability and drought.

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KEY MESSAGE: A multiparental random mating population used in sorghum breeding is amenable for the detection of QTLs related to tropical soil adaptation, fine mapping of underlying genes and genomic selection approaches. Tropical soils where low phosphorus (P) and aluminum (Al) toxicity limit sorghum [Sorghum bicolor (L.) Moench] production are widespread in the developing world. We report on BRP13R, a multiparental random mating population (MP-RMP), which is commonly used in sorghum recurrent selection targeting tropical soil adaptation. Recombination dissipated much of BRP13R's likely original population structure and average linkage disequilibrium (LD) persisted up to 2.5 Mb, establishing BRP13R as a middle ground between biparental populations and sorghum association panels. Genome-wide association mapping (GWAS) identified conserved QTL from previous studies, such as for root morphology and grain yield under low-P, and indicated the importance of dominance in the genetic architecture of grain yield. By overlapping consensus QTL regions, we mapped two candidate P efficiency genes to a ~ 5 Mb region on chromosomes 6 (ALMT) and 9 (PHO2). Remarkably, we find that only 200 progeny genotyped with ~ 45,000 markers in BRP13R can lead to GWAS-based positional cloning of naturally rare, subpopulation-specific alleles, such as for SbMATE-conditioned Al tolerance. Genomic selection was found to be useful in such MP-RMP, particularly if markers in LD with major genes are fitted as fixed effects into GBLUP models accommodating dominance. Shifts in allele frequencies in progeny contrasting for grain yield indicated that intermediate to minor-effect genes on P efficiency, such as SbPSTOL1 genes, can be employed in pre-breeding via allele mining in the base population. Therefore, MP-RMPs such as BRP13R emerge as multipurpose resources for efficient gene discovery and deployment for breeding sorghum cultivars adapted to tropical soils.

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Crop tolerance to multiple abiotic stresses has long been pursued as a Holy Grail in plant breeding efforts that target crop adaptation to tropical soils. On tropical, acidic soils, aluminum (Al) toxicity, low phosphorus (P) availability and drought stress are the major limitations to yield stability. Molecular breeding based on a small suite of pleiotropic genes, particularly those with moderate to major phenotypic effects, could help circumvent the need for complex breeding designs and large population sizes aimed at selecting transgressive progeny accumulating favorable alleles controlling polygenic traits. The underlying question is twofold: do common tolerance mechanisms to Al toxicity, P deficiency and drought exist? And if they do, will they be useful in a plant breeding program that targets stress-prone environments. The selective environments in tropical regions are such that multiple, co-existing regulatory networks may drive the fixation of either distinctly different or a smaller number of pleiotropic abiotic stress tolerance genes. Recent studies suggest that genes contributing to crop adaptation to acidic soils, such as the major Arabidopsis Al tolerance protein, AtALMT1, which encodes an aluminum-activated root malate transporter, may influence both Al tolerance and P acquisition via changes in root system morphology and architecture. However, trans-acting elements such as transcription factors (TFs) may be the best option for pleiotropic control of multiple abiotic stress genes, due to their small and often multiple binding sequences in the genome. One such example is the C2H2-type zinc finger, AtSTOP1, which is a transcriptional regulator of a number of Arabidopsis Al tolerance genes, including AtMATE and AtALMT1, and has been shown to activate AtALMT1, not only in response to Al but also low soil P. The large WRKY family of transcription factors are also known to affect a broad spectrum of phenotypes, some of which are related to acidic soil abiotic stress responses. Hence, we focus here on signaling proteins such as TFs and protein kinases to identify, from the literature, evidence for unifying regulatory networks controlling Al tolerance, P efficiency and, also possibly drought tolerance. Particular emphasis will be given to modification of root system morphology and architecture, which could be an important physiological "hub" leading to crop adaptation to multiple soil-based abiotic stress factors.

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Selection of a single dominant follicle is morphologically manifested by diameter deviation between the future dominant follicle (F1) and the future largest subordinate follicle (F2). Conventional deviation is defined as F2≥7 mm when F1 reaches ∼8.5 mm whereas, undersized deviation is if F2<7 mm when F1 reaches ∼8.5 mm. Greater frequency of undersized deviation has been temporally associated with greater circulating progesterone (P4) and greater FSH but reduced LH in observational studies. Experiment 1 was conducted to directly test if elevating P4 increased the likelihood of undersized deviation and altered circulating concentrations of LH and FSH. Experiment 2 was conducted to test if increasing LH action by treatment with exogenous porcine LH or human chorionic gonadotropin (hCG) in the presence of elevated P4, would stimulate growth of F2 and increase the likelihood of conventional deviation. Ovaries were evaluated by ultrasound and blood samples collected every 12 h after development of a new wave following follicle ablation on D6 (D0 = ovulation). Data were normalized to F1≥7.5 mm and compared using SAS software. In experiment 1 (n = 20), the CL was regressed by prostaglandin F2α treatment and heifers were randomized on D6 into control (no P4 treatment) or P4 treatment (75 mg every 12 h for 5.5 d) beginning when F1 reached ∼3 mm (P4-3 mm group) or ∼6 mm (P4-6 mm group). The P4 treatment significantly increased the frequency of undersized deviation from 0% (controls) to 54%, decreased LH by 44%, and increased FSH by 32%. In experiment 2 (n = 27) heifers were randomized on D6 into control (saline) or treatment with the LH analogs - pLH (1.25 mg porcine LH/12 h) or hCG (160 IU initially and subsequently 96 IU/24 h). Treatment with LH analogs significantly increased P4 (control, 4.6 ±â€¯0.3 ng/mL; pLH, 6.6 ±â€¯0.4 ng/mL; and hCG, 8.9 ±â€¯0.4 ng/mL) and decreased FSH (control, 0.46 ±â€¯0.03 ng/mL; combined-pLH/hCG, 0.34 ±â€¯0.02 ng/mL). However, F1 and F2 diameter and frequency of conventional (37%) and undersized (48%) deviations were similar between the control and combined-pLH/hCG groups. In conclusion, elevated P4 was directly linked to undersized deviation but the P4 effect on decreasing F2 diameter occurred independently of the P4 effects on FSH and LH concentrations.

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RESUMEN Introducción: Ramas de la arteria oftálmica contribuyen a la irrigación de diversos territorios de la fosa nasal y de los senos paranasales. Objetivo: El objetivo de nuestro estudio es describir las arterias etmoidales desde su origen intraorbitario, y su relación con las estructuras musculares y nerviosas. Material y Método: Se realizó un estudio anatómico endoscópico en 20 fosas nasales y órbitas de diez cadáveres. Resultados: La disección del plano muscular permitió definir dos espacios de entrada a la órbita. Un primer espacio entre el músculo recto inferior y músculo recto medial (área 1) y otro entre el músculo recto medial y músculo oblicuo superior (área 2). En el área 1, la arteria oftálmica discurrió superior al nervio óptico en el 90%. La arteria etmoidal anterior se observó en todos los casos inferior al músculo oblicuo superior. En el área 2, la arteria etmoidal posterior, se localizó en todos los casos superior al músculo oblicuo superior. No se identificó la arteria etmoidal media en ningún caso. El origen de la arteria supraorbitaria se identificó entre las dos arterias etmoidales. Conclusión: La comprensión anatómica del origen intraorbitario de la arteria oftálmica permite el abordaje de determinada patología intraorbitaria compleja a través de la pared medial de la órbita.

ABSTRACT Introduction: Branches of the ophthalmic artery contribute to the irrigation of various territories of the nasal cavity and paranasal sinuses. Aim: The aim of our study is to describe the intraorbital course of the ethmoidal arteries and their relationship with the muscular and nervous structures. Material and method: We performed twenty nasal cavities and orbital dissections in ten adults cadaveric heads. Results: The dissection of the muscular orbital wall allowed defining two surgical orbital corridors, between the inferior rectus and the medial rectus muscles (area 1) and between the medial rectus and the superior oblique muscles (area 2). In area 1, the ophthalmic artery crosses over the optic nerve in 90% of the cases. The anterior ethmoidal artery was observed inferior to the superior oblique muscle. In area 2, the posterior ethmoidal artery was located superior to the superior oblique muscle in all cavities. No middle ethmoidal artery was identified. The origin of the supraorbital artery was found between the two ethmoidal arteries. Conclusions: The anatomical understanding of the intraorbital origin of the arteries of the ophthalmic artery allows perform two surgical approaches through the media orbital wall.

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BACKGROUND: Phosphorus (P) fixation on aluminum (Al) and iron (Fe) oxides in soil clays restricts P availability for crops cultivated on highly weathered tropical soils, which are common in developing countries. Hence, P deficiency becomes a major obstacle for global food security. We used multi-trait quantitative trait loci (QTL) mapping to study the genetic architecture of P efficiency and to explore the importance of root traits on sorghum grain yield on a tropical low-P soil. RESULTS: P acquisition efficiency was the most important component of P efficiency, and both traits were highly correlated with grain yield under low P availability. Root surface area was positively associated with grain yield. The guinea parent, SC283, contributed 58% of all favorable alleles detected by single-trait mapping. Multi-trait mapping detected 14 grain yield and/or root morphology QTLs. Tightly linked or pleiotropic QTL underlying the surface area of fine roots (1-2 mm in diameter) and grain yield were detected at positions 1-7 megabase pairs (Mb) and 71 Mb on chromosome 3, respectively, and a root diameter/grain yield QTL was detected at 7 Mb on chromosome 7. All these QTLs were near sorghum homologs of the rice serine/threonine kinase, OsPSTOL1. The SbPSTOL1 genes on chromosome 3, Sb03g006765 at 7 Mb and Sb03g031690 at 60 Mb were more highly expressed in SC283, which donated the favorable alleles at all QTLs found nearby SbPSTOL1 genes. The Al tolerance gene, SbMATE, may also influence a grain yield QTL on chromosome 3. Another PSTOL1-like gene, Sb07g02840, appears to enhance grain yield via small increases in root diameter. Co-localization analyses suggested a role for other genes, such as a sorghum homolog of the Arabidopsis ubiquitin-conjugating E2 enzyme, phosphate 2 (PHO2), on grain yield advantage conferred by the elite parent, BR007 allele. CONCLUSIONS: Genetic determinants conferring higher root surface area and slight increases in fine root diameter may favor P uptake, thereby enhancing grain yield under low-P availability in the soil. Molecular markers for SbPSTOL1 genes and for QTL increasing grain yield by non-root morphology-based mechanisms hold promise in breeding strategies aimed at developing sorghum cultivars adapted to low-P soils.

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Acidic soils, where aluminum (Al) toxicity is a major agricultural constraint, are globally widespread and are prevalent in developing countries. In sorghum, the root citrate transporter SbMATE confers Al tolerance by protecting root apices from toxic Al3+, but can exhibit reduced expression when introgressed into different lines. We show that allele-specific SbMATE transactivation occurs and is caused by factors located away from SbMATE Using expression-QTL mapping and expression genome-wide association mapping, we establish that SbMATE transcription is controlled in a bipartite fashion, primarily in cis but also in trans Multiallelic promoter transactivation and ChIP analyses demonstrated that intermolecular effects on SbMATE expression arise from a WRKY and a zinc finger-DHHC transcription factor (TF) that bind to and trans-activate the SbMATE promoter. A haplotype analysis in sorghum RILs indicates that the TFs influence SbMATE expression and Al tolerance. Variation in SbMATE expression likely results from changes in tandemly repeated cis sequences flanking a transposable element (a miniature inverted repeat transposable element) insertion in the SbMATE promoter, which are recognized by the Al3+-responsive TFs. According to our model, repeat expansion in Al-tolerant genotypes increases TF recruitment and, hence, SbMATE expression, which is, in turn, lower in Al-sensitive genetic backgrounds as a result of lower TF expression and fewer binding sites. We thus show that even dominant cis regulation of an agronomically important gene can be subjected to precise intermolecular fine-tuning. These concerted cis/trans interactions, which allow the plant to sense and respond to environmental cues, such as Al3+ toxicity, can now be used to increase yields and food security on acidic soils.

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Follicle diameter deviation has been identified as the pivotal morphological manifestation of follicle selection, however, many of the hormonal mechanisms leading to this key event and regulating variation between individual follicular waves remain undefined. This study compared circulating FSH, LH, and P4 with the follicular dynamics during three different physiological conditions. We hypothesized that these end-points would: 1) be similar for a spontaneous wave 2 vs one induced by follicular aspiration, 2) but would differ between wave 1 and 2, and 3) between conventional (F2 > 7.0 mm at deviation) vs undersized (F2 < 7.0 mm) deviations in either wave. Holstein dairy heifers (N = 24) were studied daily during an interovulatory interval. All heifers were evaluated during wave 1 and randomized 6 days after ovulation into an induced wave 2 and a spontaneous wave 2. Values were normalized to the day of expected diameter deviation (day 0) and compared for day -2 to 0 and 0 to 2. Hypothesis 1 was supported that an induced wave 2 from ablation of follicles of wave 1 and spontaneous wave 2 have similar follicle dynamics. However, the peak FSH surge was more prominent at emergence of an induced wave 2 (P < 0.003). Hypothesis 2 was supported that waves 1 and 2 differ in follicle and hormone dynamics. Circulating P4 was lower and LH was greater (P < 0.01) with no difference in diameter of F1 but with a greater (P < 0.01) diameter of F2 on day 0 in wave 1 (7.3 ±â€¯0.2 mm) than in wave 2 (6.6 ±â€¯0.2 mm). Differences between waves were not found when each follicular wave was categorized into conventional vs undersized deviation and analyzed separately. Hypothesis 3 was supported as there were differences in circulating hormones between conventional and undersized deviations. Growth rate of F2 differed (P < 0.0005) during days -2 to 0 (conventional, 2.6 ±â€¯0.2 mm/2d; undersized, 1.4 ±â€¯0.3 mm/2d). However, circulating FSH and P4 concentration on days -1 and 0 tended to be greater (P < 0.06) in undersized than conventional deviations. In conclusion, the effect of different hormonal conditions on follicle dynamics was observed for F2 and not for F1. Furthermore, understanding the physiology that produces conventional vs undersized deviations is crucial since these categories explained most differences in follicular dynamics and circulating FSH observed in these different physiological conditions. In addition, future studies of wave 2 may be facilitated by using an induced wave 2 since it was similar to a spontaneous wave 2.

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V617F mutation in exon 14 of Janus Kinase 2 gene (jak-2) is used as a molecular marker for the diagnosis of Philadelphia negative myeloproliferative neoplasms (Phi-) such as Polycythemia Vera (PV), Essential Thrombocythemia (ET) and Primary Myelofibrosis (MFP). To detect this mutation, we used conventional polymerase chain reaction technique (PCR), a simple and inexpensive technique, however, has some drawbacks that current technology allows to solve. During the last years, more sensitive molecular techniques have been incorporated in clinical practice to support the diagnosis, prognosis and follow-up of hematological patients. For its implementation in the clinical routine should be considered technical and economic aspects, so in this work, we evaluate the Real Time PCR technique as a diagnostic method for the detection of the Jak-2-V617F mutation, using in house primers design. Our result show that the technique implemented has a concordance index of 0.87 with the conventional PCR used in the molecular diagnosis of myeloproliferative neoplasms. In addition, it has the same specificity, greater sensitivity and, shorter execution time in relation to conventional PCR. The implementation of this diagnostic method in our Hospital is technically possible and commercially convenient. (AU)

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