•We used two independent approaches to identify the beginning and end of the critical period for seed number determination in soybean.•Critical period for seed number determination occurs during the ...R3-R6 phase.•Seed number was related to biomass accumulation during the critical period.•Accumulated biomass is a better predictor of seed number than crop growth rate or duration alone.
Seed number (SN) is positively associated with aboveground dry matter (ADM) accumulation in most crop species. In soybean, there are discrepancies among studies relative to the start and end of the critical period for seed number determination. The objective of this study was to more precisely identify those two stages. To do so, we followed two approaches: (i) analyses of experimental data where differences in SN occurred as a result of variation in crop growth due to weather and management practices and (ii) review of published experiments where soybean was subjected to artificial stresses during specific crop phases. Following the first approach, we analyzed the relationships between SN versus ADM accumulation and its components, crop growth rate (CGR) and duration, for different reproductive phases using data from experiments that portrayed a wide range of environments and management practices. In the second approach, we compared SN values in stressed versus non-stressed treatments. Accumulated ADM during the R3 to R6 phase explained ca. 70 % of the variation in SN across experiments. The CGR during R3-R6 was also a good predictor of SN, but it had lower explanatory power compared with accumulated ADM, because CGR did not account for changes in duration of critical period across experiments. Review of published data, wherein soybean crops were subjected to artificial stresses during different reproductive phases, confirmed that the R3-R6 phase is a critical phase for SN determination in soybean. Key findings of this study were: (i) critical period for SN determination in soybean occurs during the R3-R6 phase and (ii) accumulated ADM during the critical period is a better predictor of SN compared with CGR because it accounts for differences in the duration of the critical period as a result of weather and management.
For sunflower, there are reports showing reduced distance between rows could be neutral, beneficial or counterproductive. In well-watered crops, yield response to distance between rows has been ...analysed in terms of fractional photosynthetically active radiation (PAR) interception during the most critical periods of grain set. The aim of this work was to advance our understanding of the interaction between row distance, water availability and cultivar type analysing yield responses in terms of capture of radiation. Five experiments were conducted in the southern Pampas of Argentina. The combination of seasons, sites, soil depth, sowing dates and cultivars generated a wide range of growing conditions, including contrasting water regimes. Crops in wide rows intercepted less radiation than their counterparts in narrow rows in all experiments, with significant differences in 6 of 14 cases (
P<0.05). Zenit, a short-season hybrid, consistently intercepted less radiation than its long-season counterparts (
P<0.01). Yield response to narrow rows was significant for Zenit in four out of five experiments, whereas long-season hybrids only increased yield in one experiment. For crops with low or moderate water deficit, yield did not respond to narrow rows when conditions were conducive to full interception in wide-row crops, but yield increased up to 15% when fractional PAR interception in wide-row crops was about 70%. For crops with severe water deficit, yield response ranged from 25% reduction when wide-row crops were close to full interception to 25% increase when fractional PAR interception was about 0.6. Increase in yield with narrow rows was largely related to increased grain number, whereas yield reductions were primarily related to reduced grain mass. Change in yield in response to row spacing was a linear function of change in fractional PAR interception; the rate of change in yield per unit change in fractional PAR interception fell from 1.3%/% in severely stressed crops to 0.24%/% in crops with low or moderate stress.
Introducción: El objetivo de este estudio fue comparar la tasa de hernia incisional (HI) tras la extracción de piezas operatorias por mini-laparatomia media periumbilical (MM) versus mini-laparotomía ...transversa suprapúbica (MTS) en cirugía laparoscópica por cáncer colorrectal (CLCC), y evaluar factores asociados. Material y método: Estudio de cohorte no concurrente de pacientes consecutivos sometidos a CLCC en nuestro centro entre septiembre 2006 y diciembre 2017, cuya pieza operatoria fuese extraída por MM o MTS y contaran con un control tomográfico en el seguimiento. El diagnóstico de HI se realizó mediante tomografía computada. Se evaluaron tasas de HI según sitio de extracción y se realizó regresión logística para identificar factores asociados. Resultados: Se identificaron 1090. 254 cumplieron los criterios de inclusión. La edad media fue 63 años (53,5% son hombres) e IMC de 26,4 kg/m2. El sitio de extracción fue MTS en 53,1% y MM en 46,9%. Se identificó un total de 41 (34,5%) HI en el grupo de MM versus 17 (12,6%) en MTS (p=0,001) en TAC de seguimiento realizado en una mediana de 18 meses (RIC 12-32) postoperatorios. En la regresión logística, la MM (OR = 3,33, IC 95% 1,72-7,14, p<0,001) y la presencia de patología bronquial obstructiva se asociaron de manera independiente con HI (OR = 3,45, IC 95% 1,11-11,11, p= 0,03). Conclusión: La MTS se asocia a menor tasa de HI que la MM en pacientes sometidos a CLCC. Esto se debe tener en consideración al momento de elegir el sitio de extracción de pieza operatoria en CLCC.
Highlights ► AVT presents multiple putative sites of action across the HPG axis, in vitro . ► AVT expression in the brain is differentially related to distinct social classes. ► For the first time in ...a teleost, AVT-ir was observed within testis’ cells.
Present status of Accelerator-Based BNCT Kreiner, Andres Juan; Bergueiro, Javier; Cartelli, Daniel ...
Reports of Practical Oncology and Radiotherapy,
03/2016, Letnik:
21, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Abstract Aim This work aims at giving an updated report of the worldwide status of Accelerator-Based BNCT (AB-BNCT). Background There is a generalized perception that the availability of accelerators ...installed in hospitals, as neutron sources, may be crucial for the advancement of BNCT. Accordingly, in recent years a significant effort has started to develop such machines. Materials and methods A variety of possible charged-particle induced nuclear reactions and the characteristics of the resulting neutron spectra are discussed along with the worldwide activity in suitable accelerator development. Results Endothermic7 Li(p,n)7 Be and9 Be(p,n)9 B and exothermic9 Be(d,n)10 B are compared. In addition to having much better thermo-mechanical properties than Li, Be as a target leads to stable products. This is a significant advantage for a hospital-based facility.9 Be(p,n)9 B needs at least 4–5 MeV bombarding energy to have a sufficient yield, while9 Be(d,n)10 B can be utilized at about 1.4 MeV, implying the smallest possible accelerator. This reaction operating with a thin target can produce a sufficiently soft spectrum to be viable for AB-BNCT. The machines considered are electrostatic single ended or tandem accelerators or radiofrequency quadrupoles plus drift tube Linacs. Conclusions7 Li(p,n)7 Be provides one of the best solutions for the production of epithermal neutron beams for deep-seated tumors. However, a Li-based target poses significant technological challenges. Hence, Be has been considered as an alternative target, both in combination with (p,n) and (d,n) reactions.9 Be(d,n)10 B at 1.4 MeV, with a thin target has been shown to be a realistic option for the treatment of deep-seated lesions.
Reproductive biotechnologies such as in vitro fertilization (IVF) and somatic cell nuclear transfer (SCNT) enable improved reproductive efficiency of animals. However, the birth rate of in ...vitro-derived embryos still lags behind that of their in vivo counterparts. Thus, it is critical to develop an accurate evaluation and prediction system of embryo competence, both for commercial purposes and for scientific research. Previous works have demonstrated that in vitro culture systems induce alterations in the relative abundance (RA) of diverse transcripts and thus compromise embryo quality. The aim of this work was to analyze the RA of a set of genes involved in cellular stress (heat shock protein 70-kDa, HSP70), endoplasmic reticulum (ER) stress (immunoglobulin heavy chain binding protein, Bip; proteasome subunit β5, PSMB5) and apoptosis (BCL-2 associated X protein, Bax; cysteine aspartate protease-3, Caspase-3) in bovine blastocysts produced by IVF or SCNT and compare it with that of their in vivo counterparts. Poly (A) + mRNA was isolated from three pools of 10 blastocysts per treatment and analyzed by real-time RT-PCR. The RA of three of the stress indicators analyzed (Bax, PSMB5 and Bip) was significantly increased in SCNT embryos as compared with that of in vivo-derived blastocysts. No significant differences were found in the RA of HSP70 and Caspase-3 gene transcripts. This study could potentially complement morphological analyses in the development of an effective and accurate technique for the diagnosis of embryo quality, ultimately aiding to improve the efficiency of assisted reproductive techniques (ART).
indeterminate Western blot (WB) patterns are a major concern for diagnosis of human T-cell lymphotropic virus type 1 (HTLV-1) infection, even in non-endemic areas.
(a) to define the prevalence of ...indeterminate WB among different populations from Argentina; (b) to evaluate if low proviral load (PVL) is associated with indeterminate WB profiles; and (c) to describe mutations in LTR and tax sequence of these cases.
Among 2031 samples, 294 were reactive by screening. Of them, 48 (16.3%) were WB indeterminate and of those 15 (31.3%) were PCR+. Quantitative real-time PCR (qPCR) was performed to 52 HTLV-1+ samples, classified as Group 1 (G1): 25 WB+ samples from individuals with pathologies; Group 2 (G2): 18 WB+ samples from asymptomatic carriers (AC); and Group 3 (G3): 9 seroindeterminate samples from AC. Median PVL was 4.78, 2.38, and 0.15 HTLV-1 copies/100 PBMCs, respectively; a significant difference (p=0.003) was observed. Age and sex were associated with PVL in G1 and G2, respectively. Mutations in the distal and central regions of Tax Responsive Elements (TRE) 1 and 2 of G3 were observed, though not associated with PVL.The 8403A>G mutation of the distal region, previously related to high PVL, was absent in G3 but present in 50% of WB+ samples (p = 0.03).
indeterminate WB results confirmed later as HTLV-1 positive may be associated with low PVL levels. Mutations in LTR and tax are described; their functional relevance remains to be determined.
Abstract Timing of breeding to an optimal season is a requirement for a successful reproductive outcome in seasonally breeding species. Photoperiodic signals are capable of modifying the reproductive ...behaviour and reproductive systems in several vertebrate species. The cichlid fish Cichlasoma dimerus shows highly organized breeding activities and different social status. The aim of this study is to test whether C. dimerus reproductive behaviour (male aggressive behaviour and female choice) and reproductive physiology (GnRH3 morphometric parameters, pituitary hormones content and organ-somatic indexes) are modulated by photoperiod. Before spawning, dominant pairs were isolated and kept in opposite tanks of 20 l for one week, so they could see each other but not physically interact. Afterwards, a group was exposed for four weeks to a short photoperiod (8 h light:16 h dark) (short photoperiod exposed animals: SP) while another group was exposed to a long photoperiod (14 h light:10 h dark) (long photoperiod exposed animals: LP). Temperature was maintained constant. Behavioural experiments showed that male aggression related to territory selection and its defence is reduced in SP males. Further, SP females were never chosen. At the brain level we demonstrated that GnRH3 neuronal optical density of staining was reduced. Finally, at the pituitary level we showed that SP males showed low levels of β-LH, PRL and GH in the pituitary, and that SP females showed no significant differences in the pituitary content of any hormone. Taken all together these results suggest that in C. dimerus the photoperiod is a relevant environmental cue related to reproductive behaviour and physiology.
Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) play key roles in vertebrate gametogenesis and steroidogenesis. They are mainly synthesized in the pituitary gland. While investigating ...the ontogeny of FSH and LH cells in the cichlid fish Cichlasoma dimerus by immunohistochemistry (IHC), we unexpectedly found immunoreactive neurons in the preoptic area, sending their projections through different brain areas and neurohypophysis. Our previous work using Western blot and IHC techniques applied to the adult brain confirmed these findings. To further demonstrate the extrapituitary expression of these hormones, we performed RT-PCR detecting sequences coding for beta-FSH and beta-LH subunits in the C. dimerus pituitary and brain (preoptic-hypothalamic area). The expression of these transcripts in both organs was consistent with their peptide expression showing a high sequence homology when compared with other phylogenetically related fish. An individual pituitary in vitro culture system was utilized to study the possible modulatory effect of brain-derived gonadotropins on pituitary hormone secretion. Pituitary explants were cultured with different concentrations of LH or FSH, and the culture media were analyzed by Western blot. Exogenous LH produced a dose-dependent increase in pituitary beta-LH, beta-FSH and somatolactin (SL) releases. No effect was observed on growth hormone (GH). The effect on prolactin (PRL) was not consistent among treatments. Exogenous FSH produced an inhibition in beta-LH release, dose-dependent increases in beta-FSH and SL releases, and no effect on PRL and GH releases. These findings support the concept of regulation of pituitary trophic hormones by brain-derived gonadotropins.
In this work we describe for the first time the social and reproductive behavior of the Neotropical fish Cichlasoma dimerus (Heckel, 1840) Perciformes: Cichlidae, endemic to the Paraná River basin, ...using a comprehensive-integral approach, including morphological and physiological features. This substrate breeding fish has biparental care of the fry and presents a dominance hierarchy that determines access to breeding territories among males, and to males with territories among females. Gregarious behavior associated with a pale body color, was observed before reproductive behaviors started. Afterwards, a dominance hierarchy was established through aggressive interactions. Territorial individuals had bright body color patterns and non territorial an opaque grey one. Black ventral coloration was associated with reproductive individuals. Courtship displays, which were similar to threatening displays, had the common effect of increasing the visible area of the individual. The dominant male was always the largest one suggesting that size is probably a major factor determining the hierarchy establishment and that these intra-sexually selected traits may have been reinforced by inter-sexual selection. Reproductive males had higher pituitary levels of β-follicle stimulating hormone (β-FSH) and somatolactin (SL) than non reproductive ones, while no differences were found among females. No differences were found among male gonadosomatic indexes. Non reproductive individuals had higher plasma cortisol levels for both sexes. It is possible that dominant reproductive individuals may be inhibiting reproduction of subordinate fish through physical contact, increasing their cortisol levels and diminishing FSH and SL pituitary content. However, this was not reflected as an inhibition at the gonadal level in our experimental design.
En este trabajo se describen por primera vez el comportamiento social y reproductivo del pez cíclido neotropical Cichlasoma dimerus (Heckel, 1840) Perciformes: Cichlidae, endémico de la cuenca del Paraná, desde un enfoque integral y abarcador, incluyendo características morfológicas y fisiológicas. Éste pez incubador de substrato, tiene cuidado biparental de las crías y presenta una jerarquía de dominancia que determina el acceso a territorios reproductivos entre los machos, y a machos con territorios entre las hembras. Se observó un comportamiento gregario con una coloración corporal pálida característica, antes que comenzaran los comportamientos reproductivos. Luego, una jerarquía de dominancia se estableció a través de interacciones agresivas. Los individuos territoriales presentaron patrones de coloración corporal brillantes y los individuos no territoriales uno gris opaco. Una coloración ventral oscura fue observada asociada a individuos reproductivos. Los despliegues de cortejo fueron similares a los de amenaza y tuvieron la característica común de aumentar el área visible de los peces. El macho dominante fue siempre el más grande, sugiriendo que probablemente la fuerza (tamaño) es un factor preponderante determinando el establecimiento de las jerarquías y que éstas características seleccionadas intrasexualmente pueden haber sido reforzadas por selección intersexual. Los machos reproductivos presentaron un mayor contenido hipofisario de β-FSH y SL que aquellos no reproductivos, mientras que no se encontraron diferencias entre las hembras. No se encontraron diferencias entre los índices gonadosomáticos de los machos. Los individuos no reproductivos presentaron niveles plasmáticos mayores de cortisol para ambos sexos. Aunque los individuos reproductivos dominantes podrían estar inhibiendo la reproducción de los peces menos dominantes a través de interacciones de contacto físico, aumentando sus niveles de cortisol y disminuyendo el contenido hipofisario de FSH y SL, esto no se vería reflejado a nivel gonadal en nuestro diseño experimental.
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