Potency Ratio Research Articles

Heritability of Anatomical Characteristics in Cherry Interspecific Hybrids

The aim of this study was to assess the stem anatomical structure of divergent cherry germplasm and estimate genetic variation and heritability as well as hybrid enhancement for anatomical traits of cherry interspecific hybrids. Plant material included 18 cherry genotypes representing seven species and species hybrids. Analyses included detailed anatomical investigations of 1- and 2-year-old stems’ macro and micro cross-sectional characteristics, theoretical hydraulic conductance calculations, as well as estimations of genotypic and phenotypic variances, coefficients of variation, broad sense heritability, hybrid enhancement, and potence ratio. Average vessel lumen areas and percentages of vessels belonging to different size classes exhibited moderate to high heritability (more than 60%). In contrast, macro-anatomical characteristics—cambial-induced secondary thickening and production of secondary wood (xylem) and secondary cortex (phloem), appeared to be more environmentally sensitive. The high heritability of xylem vessel properties and low heritability of cross-sectional traits, along with previous knowledge regarding cambial-induced secondary thickening observed in the same germplasm, could be used to inform parentage choice for rootstock breeding crosses. The results support the hypothesis that xylem vessel size is primarily under genetic control and exhibits different degrees of dominance—partial (very close to better parent), full, and overdominance. It is presumed that the MSU rootstocks ‘Cass’ and ‘Clare’, followed by ‘Benzie’ and ‘Lake’ would have the greatest size-controlling effect on grafted cherry varieties, while Prunus maackii, the P. maackii × ‘Montmorency’ hybrid , and ‘Montmorency’ × ‘Colt’ hybrid would act as invigorating rootstocks. Our findings suggest that future hybrids between Prunus cerasus and Prunus fruticosa, the ‘weaker’ parental species characterized by smaller vessels, would result in rootstock candidates with better size-controlling effect, while crossings between P. fruticosa and Prunus mahaleb should have well-balanced vessel lumen areas and cambial activity, which is a prerequisite for successful adaptation to changing environmental conditions.

Breeding Melon (Cucumis melo L.) for resistance to powdery mildew and fruit quality characteristics.

This study was conducted during the period from 2015 to 2017 to study resistance of powdery mildew in eight melon inbred lines and their hybrids in order to reduce losses in quality and yield. Eight different genetically inbred lines of melon were selfed for six generations to ensure homozygosity. They have been self-pollinated and intercrossed in a half diallel mating design to obtain 28 melon hybrids in 2015. Thirty six melon genotypes (8 inbred Lines and 28 produced hybrids) were evaluated for their reaction to powdery mildew in 2016. The results showed that P5, P6, P7 and P8 of inbred lines, and all hybrids that contain P6 [(P1) X(P6), (P2) X(P6), (P3) X(P6), (P4) X(P6), (P5) X(P6), (P6) X(P7) and (P6) X(P8)] beside P5X P7, P5X P8 and P7X P8 showed low infection (between 1-12.5%) that is meaning they are resistant. The genetic study showed that most hybrids appeared significant negative heterosis over its mid parent. On the contrary, most studied hybrids appeared significant positive heterosis over its better parent. The most potence ratio estimates indicated dominance towards powdery mildew resistance. In 2017 at WADY El-Natroon, The 36 hybrids were evaluated along with their parents to determine heterosis and potence ratio for the economic traits, viz., days to picking, early yield/plant, total yield/plant, average fruit weight, fruit shape index, netting, total soluble solids and flesh thickness. The results showed highly significant mean squares for all of the studied traits. Some crosses revealed highly significant and significant mid-parent and better-parent heterosis for many of studied traits. The inbred lines P5, P6 and P7 were resistant to powdery mildew and had good horticultural characteristics. They were the best and promising inbred lines.

Life History and Length Based-Spawning Potential Ratio (LB-SPR) of Exploited Demersal Fish Stock (Upeneus sp) in Sunda Strait.

Length Based-Spawning potential ratio (LB-SPR) is the most popular technique in worldwide that use for data-poor fisheries management. Based on this situation, LB-SPR tries to apply in demersal fish is Kuniran (Upeneus sp) in small scale fisheries search in Sunda Strait to learn about the sustainability potency both of maturity and recruitment potency from spawning potency ratio. Length data was collected by team research from 2014 to 2019 (except 2017, there is no sampling activity), which from Bogor University. Research result show that asymptotic length (L∞)is 302,10 mm, natural mortality (M) 0,49, Bartalanffy growth (k) 1,03. The length at 50% maturity size (Lm50) is 134,80 mm, length at 95% mature size (Lm95) is 147 mm and relatively higher than the selectivity size. The spawning potential ratio found at 1-6% with the annual average is 2% per year. The conclusion is this research shown that recruitment potency and recovery of depleted stock relatively low and potential un-sustain. The life history and LB-SPR information need to formulate a new strategy to manage size selectivity and fishing intensity in the Sunda Strait.

The use of benchmark dose uncertainty measurements for robust comparative potency analyses.

The Benchmark Dose (BMD) method is the favored approach for quantitative dose-response analysis where uncertainty measurements are delineated between the upper (BMDU) and lower (BMDL) confidence bounds, or confidence intervals (CIs). Little has been published on the accurate interpretation of uncertainty measurements for potency comparative analyses between different test conditions. We highlight this by revisiting a previously published comparative in vitro genotoxicity dataset for human lymphoblastoid TK6 cells that were exposed to each of 10 clastogens in the presence and absence (+/-) of low concentration (0.25%) S9, and scored for p53, γH2AX and Relative Nuclei Count (RNC) responses at two timepoints (Tian et al., 2020). The researchers utilized BMD point estimates in potency comparative analysis between S9 treatment conditions. Here we highlight a shortcoming that the use of BMD point estimates can mischaracterize potency differences between systems. We reanalyzed the dose responses by BMD modeling using PROAST v69.1. We used the resulting BMDL and BMDU metrics to calculate "S9 potency ratio confidence intervals" that compare the relative potency of compounds +/- S9 as more statistically robust metrics for comparative potency measurements compared to BMD point estimate ratios. We performed unsupervised hierarchical clustering that identified four S9-dependent groupings: high and low-level potentiation, no effect, and diminution. This work demonstrates the importance of using BMD uncertainty measurements in potency comparative analyses between test conditions. Irrespective of the source of the data, we propose a stepwise approach when performing BMD modeling in comparative potency analyses between test conditions.

A randomized, double-blinded comparative study of phenylephrine infusion and norepinephrine infusion for the prevention and treatment of spinal anesthesia-induced hypotension in elective and emergency cesarean deliveries

Context and Aims: Among vasopressors used to treat postspinal hypotension (PSH) in cesarean sections (CS), phenylephrine (PE) is the preferred drug at present but reflex bradycardia and thus reduction in cardiac output still pose a concern. Norepinephrine (NE), with its better pharmacological properties, may be a better alternative to overcome this risk. Hence, we did this study intending to compare both the drugs. Materials and Methods: A double-blinded, randomized, controlled trial (RCT) was carried out on 70 patients, 35 in each group-group P (PE) and group N (NE) undergoing CS, to compare and evaluate the efficacy of both drugs for preventing and treating PSH. Patients in Group P and Group N were given intravenous infusion of PE at the rate of 50 μg/min and NE at the rate of 2.5 μg/min, respectively, after the intrathecal injection of bupivacaine. The number of intermittent bolus doses required, heart rate, and mean arterial pressure (MAP) at predefined intervals were noted. Results: The incidence of hypotension calculated from the number of bolus doses required was lower in Group N than in Group P for the initial 15 min (P Conclusion: This study suggests that NE infusion is superior to PE infusion when used in the potency ratio of 20:1, to prevent and treat PSH in CS, with a lesser number of side effects.

General Performance, Heterosis and Potence Ratio for Some Important Characters Using Complete Diallel Cross among Five Inbred Lines of Cucumber (Cucumis sativus, L.) under Greenhouse Conditions

Self-pollination for five selected cucumber indeterminate inbred lines was carried out for two generations, during summer and autumn season of 2016, to confirm their purity as parents in a hybrid breeding program. Complete diallel cross among the five inbred lines were conducted during summer season of 2017 to produce all possible hybrids combinations. The twenty-five genotypes (Five parents, their 10 F1 hybrids and 10 F1 reciprocals) were grown and evaluated under greenhouse conditions in three sowing dates (mid of each months February, March and May respectively) for two successive years (2018 and 2019) in a randomized complete block design with three replicates. Mean performance, heterosis % and Potence ratio were estimated, for characteristics of vegetative, flowering and fruit quality, yield and its components. The results clarified that there were significant and high significant differences between genotypes of the study in all studied traits. The best parents for vegetative growth, yield components and fruit quality traits were P4 followed by P5 and P2. Therefore, the three parental inbred liens P4, P5andP2 can be selected as tester parents, and for the sharing in hybrid combinations to predict the best hybrids. The best hybrid combinations for most traits were found to be F1hybrids of P2XP4 and P1XP5, and their reciprocals which recorded the highest productivity for total yield, number of fruits/plant and high average fruit weight and other fruit quality traits. Therefore, F1hybrids P2XP4 and P1XP5 and their reciprocals could be generally, considered the most important ones and promising new produced cucumber hybrids of this study. The results proved the existence of marked potence ratios and heterosis, either over the mid-parental value or that of the better parent for all studied traits. Heterosis values for vegetative measurements, early yield, total yield, number of fruits, average fruit weight and fruit length traits were positive and significant in the most crosses, while potence ratio estimates were positive and greater than one. Therefore, the inheritance of these traits involved complete to over dominance for high over low values. However, heterosis values for flowering and fruiting measurements were negative and significant in most crosses, also potence ratio estimates were negative and greater than one. Therefore, the inheritance of these traits seemed to have dominance to overdominance nature for early over late flowering and fruiting.

Heterosis, Potence Ratio and Correlation of Vegetative, Yield and Quality Traits in Tomato Genotypes and their Performance under Arid Region

Background: The possibility of selecting the best genotypes to develop good hybrid varieties of tomatoes, as well as heterosis, potence ratio and correlation of vegetative characteristics, yield and quality in tomato genotypes and their performance under arid region.Methods: Four commercial tomato cultivars (Money Maker, Pakmore VF, Strain-B and Tanshet Star) and two breeding lines (L05960 and TL01899) and their 15 F1 hybrids, using a half-diallel cross, under arid conditions were used to estimate heterosis, potence ratio and correlation coefficients among all possible pairs of important tomato traits.Result: various degrees of dominance effects for some traits were detected in the general performances of the F1 hybrids, while, other traits illustrated the presence of partial- to under-recessiveness. Heterosis percentages reflected positive desirable effects in ten F1 hybrids for some traits. Most F1 hybrids outperformed their respective parents for fruit set, fruit length, fruit diameter, total soluble solids, fruit dry weight, number of fruits per plant and total fruit yield per plant. Some of the genotypes (i.e., parents and/ or hybrids) offer opportunities as a genetic source of heat tolerant breeding genetic material adapted to high temperature under the arid conditions reported in this study. Significant positive and desirable correlations were found between 41 possible pairs of traits, whereas significant negative and undesirable correlations were found between 13 possible pairs of the traits.

Comparison of Analgesic and Adverse Effects of Oxycodone- and Fentanyl-Based Patient-Controlled Analgesia in Patients Undergoing Robot-Assisted Laparoscopic Gastrectomy Using a 55:1 Potency Ratio of Oxycodone to Fentanyl: A Retrospective Study.

PurposeOxycodone has affinities for both kappa- and mu-opioid receptors. Therefore, it has been used for postoperative analgesia of surgeries in which visceral pain is expected to be the main cause of pain. However, there are few studies of the 55:1 potency ratio of oxycodone to fentanyl when using it as intravenous patient-controlled analgesia (IV-PCA). Thus, we compared the analgesic and adverse effects of IV-PCA using the 55:1 potency ratio of oxycodone to fentanyl in patients who underwent robot-assisted laparoscopic gastrectomy.Patients and MethodsThis retrospective study included 100 patients using an automatic PCA pump with oxycodone or fentanyl who underwent robot-assisted laparoscopic gastrectomy between January and November 2017. All patients were provided with an IV-PCA consisting of 20 μg/kg of fentanyl or 1.1 mg/kg of oxycodone mixed with 0.9% normal saline solution to a total volume of 250 mL, which was infused basally at a rate of 0.1 mL/h with a bolus dose of 1 mL and lockout time of 6 min. The primary and secondary endpoints were to evaluate the efficacies of IV-PCA using the 55:1 potency ratio of oxycodone to fentanyl on analgesic and adverse effects.ResultsPain intensity on arrival at the post-anesthesia care unit (PACU; 3.6±1.4 vs 4.4±2.0, P=0.031) and additional analgesic requirement within an hour after surgery (including the PACU period) (12% vs 37%; P=0.005) were significantly lower in the oxycodone group (n=49) than in the fentanyl group (n=51). Regarding adverse effects, the rate of postoperative nausea within 1 h after surgery (2% vs 16%; P=0.031) was also significantly lower in the oxycodone group than that in the fentanyl group.ConclusionOxycodone-based IV-PCA by dose calculations with a 55:1 potency ratio may achieve better analgesia without any significant adverse effects, when using IV-PCA in patients undergoing robot-assisted laparoscopic gastrectomy.

Sialorphin Potentiates Effects of [Met5]Enkephalin without Toxicity by Action other than Peptidase Inhibition.

This dose-response study investigated the effects of sialorphin on [Met5]enkephalin (ME)-induced inhibition of contractions in mouse vas deferens and antinociception in male rats. Differences were compared among combinations of three chemical peptidase inhibitors: amastatin, captopril, and phosphoramidon. The ratio of potencies of ME in mouse vas deferens pretreated with both sialorphin (100 µM) and a mixture of the three peptidase inhibitors (1 µM each) was higher than that with the mixture of peptidase inhibitors alone at any dose. Intrathecal administration of sialorphin (100-400 nmol) significantly and dose dependently increased ME (3 nmol)-induced antinociception with the mixture of three peptidase inhibitors (10 nmol each). The degree of antinociception with a combination of any two of the peptidase inhibitors (10 nmol each) in the absence of sialorphin was less than that in the presence of sialorphin (200 nmol). Pretreatment with both sialorphin (200 nmol) and the mixture of three peptidase inhibitors (10 nmol each) produced an approximately 100-fold augmentation in ME (10 nmol)-induced antinociception, but without signs of toxicity such as motor dysfunction in rats. Radioligand receptor binding assay revealed that sialorphin did not affect either binding affinity or maximal binding capacity of [d-Ala2,N-MePhe4,Gly-ol5]enkephalin. These results indicate that sialorphin potentiates the effects of ME without toxicity by a mechanism other than peptidase inhibition and with no effect on its affinity to µ-opioid receptors. SIGNIFICANCE STATEMENT: Sialorphin is regarded as an endogenous peptidase inhibitor that interacts with enkephalin-degrading enzymes. The results of these in vitro and in vivo studies confirm that sialorphin potentiates the effects of [Met5]enkephalin without toxicity by an action other than peptidase inhibition. This suggests that sialorphin offers the advantage of reducing or negating the side effects of opioid drugs and endogenous opioid peptides.

The Pitfalls of Heterosis Coefficients.

Heterosis (hybrid vigour) is a universal phenomenon of crucial agro-economic and evolutionary importance. We show that the most common heterosis coefficients do not properly measure deviation from additivity because they include both a component accounting for “real” heterosis and a term that is not related to heterosis, since it is derived solely from parental values. Therefore, these coefficients are inadequate whenever the aim of the study is to compare heterosis levels between different traits, environments, genetic backgrounds, or developmental stages, as these factors may affect not only the level of non-additivity, but also parental values. The only relevant coefficient for such comparisons is the so-called “potence ratio”. Because most heterosis studies consider several traits/stages/environmental conditions, our observations support the use of the potence ratio, at least in non-agronomic contexts, because it is the only non-ambiguous heterosis coefficient.

Validated TLC-Contact Bioautography Method for Identification of Kanamycin Sulfate in Injection Preparation

Background: TLC-contact bioautography is one of an effective method for identification antibiotics, by which many antibiotics could be identification and determination simultaneously. Objective: To evaluate kanamycin sulfate in injection preparations based on its inhibitory activity against Escherichia coli ATCC 8739 as test organism. Methods: Sample and standard solutions were spotted onto TLC silica gel 60 F254 plate and developed in 10% potassium dihydrogen phosphate solutionas as mobile phase. The TLC-contact bioautography method was validated according to USP guidelines by considering specificity, LOD, LOQ, linearity, accuracy and precision parameters. Results: The TLC-contact bioautography method was found to be high sensitivity with LOD of 0.75 µg and LOQ 2.31 µg. Linearity range of 100-350 µg/mL with r = 0.9993 and linear regression equation was y = 0.0019x + 0.0338. The recovery obtained from addition of blank samples by three different concentrations of kanamycin sulfate standard was 101.40% ¬+ 2.02%. The precision of the method was good with coefficient of variation 0.080%. The TLC-contact bioautography method was supported by determination of kanamycin sulfate potency ratio in the injection preparation and kanamycin sulfate standard using 3-3 design. Random block design obtained the potential for kanamycin sulfate in injection preparations compared to kanamycin sulfate standard was 100.6%. Conclusion: The TLC-contact bioautography for kanamycin sulfate in injection preparations could be applied to the quality control analysis of the investigated drugs.

The Intriguing Effects of Substituents in the N-Phenethyl Moiety of Norhydromorphone: A Bifunctional Opioid from a Set of "Tail Wags Dog" Experiments.

(−)-N-Phenethyl analogs of optically pure N-norhydromorphone were synthesized and pharmacologically evaluated in several in vitro assays (opioid receptor binding, stimulation of [35S]GTPγS binding, forskolin-induced cAMP accumulation assay, and MOR-mediated β-arrestin recruitment assays). “Body” and “tail” interactions with opioid receptors (a subset of Portoghese’s message-address theory) were used for molecular modeling and simulations, where the “address” can be considered the “body” of the hydromorphone molecule and the “message” delivered by the substituent (tail) on the aromatic ring of the N-phenethyl moiety. One compound, N-p-chloro-phenethynorhydromorphone ((7aR,12bS)-3-(4-chlorophenethyl)-9-hydroxy-2,3,4,4a,5,6-hexahydro-1H-4,12-methanobenzofuro[3,2-e]isoquinolin-7(7aH)-one, 2i), was found to have nanomolar binding affinity at MOR and DOR. It was a potent partial agonist at MOR and a full potent agonist at DOR with a δ/μ potency ratio of 1.2 in the ([35S]GTPγS) assay. Bifunctional opioids that interact with MOR and DOR, the latter as agonists or antagonists, have been reported to have fewer side-effects than MOR agonists. The p-chlorophenethyl compound 2i was evaluated for its effect on respiration in both mice and squirrel monkeys. Compound 2i did not depress respiration (using normal air) in mice or squirrel monkeys. However, under conditions of hypercapnia (using air mixed with 5% CO2), respiration was depressed in squirrel monkeys.

Does In Vitro Potency Predict Clinically Efficacious Concentrations?

The in vitro affinity of a compound for its target is an important feature in drug discovery, but what remains is how predictive in vitro properties are of in vivo therapeutic drug exposure. We assessed the relationship between in vitro potency and clinically efficacious concentrations for marketed small molecule drugs (n = 164) and how they may differ depending on therapeutic indication, mode of action, receptor type, target localization, and function. Approximately 70% of compounds had a therapeutic unbound plasma exposure lower than in vitro potency; the median ratio of exposure in relation to in vitro potency was 0.32, and 80% had ratios within the range of 0.007 to 8.7. We identified differences in the in vivo–to–in vitro potency ratio between indications, mode of action, target type, and matrix localization, and whether or not the drugs had active metabolites. The in vitro–assay variability contributions appeared to be the smallest; within the same drug target and mode of action the within‐variability was slightly broader; but both were substantially less compared with the overall distribution of ratios. These data suggest that in vitro potency conditions, estimated in vivo potency, required level of receptor occupancy, and target turnover are key components for further understanding the link between clinical drug exposure and in vitro potency.

Heterotic Potential, Potence Ratio, Combining Ability and Genetic Control of Quality and Yield Traits in Bell Pepper Under Net-House Conditions of NW Himalayas

The present experiment was carried out with the aim of identifying outstanding specific combiners and best parental lines along with the understanding of genetic control of fruit quality and yield traits of bell pepper under net-house conditions in northwestern Himalayas of India. Eight inbred lines were crossed in half diallel manner, and the resulted twenty-eight F1 hybrids along with a standard check variety were evaluated under net-house conditions. California Wonder and Solan Bharpur parental lines were found to be the best combiner for earliness, whereas Yolo Wonder, California Wonder, Nishath-1 and UHFBP-3 reported as best parental line for fruit quality, yield and yield contributing traits based on their general combining effects. Solan Bharpur × Yolo Wonder, Yolo Wonder × Nishath-1, California Wonder × Solan Bharpur, California Wonder × UHFBP-3 and UHFBP-3 × KC-12 cross-combinations found outstanding based on heterosis and specific combining ability for most of the traits under net-house condition. The present studied hybrids illustrated the presence of over-dominance effect for yield and yield contributing traits under study. Predominance of nonadditive gene action for all the characters suggested the usefulness of exploitation of hybrid vigor.

INSECTICIDAL POTENTIAL OF CITRUS AND MANGO ESSENTIAL OILS AND SELECTED CONSTITUENTS ON SILVERLEAF WHITEFLY1

ABSTRACT Bemisia tabaci is a cosmopolitan pest responsible for causing harm to crops in the agricultural hub of Petrolina in the state of Pernambuco, Brazil. We investigated the lethal and sublethal effects of vapors from essential oils obtained through hydrodistillation of the peels of four species of Citrus and the latex from Mangifera indica (var. “rosa” and “espada”) on B. tabaci. The chemical analysis by Gas chromatography coupled to mass spectrometry of the oils led to the identification of 71 constituents, with limonene as the major component of the Citrus oils and terpinolene as the major component of the M. indica oils. B. tabaci was more susceptible to Citrus aurantiifolia (LC50 = 0.70 µL L-1 air) and C. limon (LC50 = 1.77 µL L-1 air) oils, which had the same level of toxicity. Citrus and M. indica oils also led to a reduction in the fecundity of the pest. The lethal and sublethal action of the constituents linalool, α-terpineol, α-pinene, β-pinene, terpinolene and limonene is also discussed. The toxicity of the oils investigated herein associated with the reduction in fecundity is a considerable advantage in the management of B. tabaci. However, for practical use of these oils as a novel insecticide to proceed, further research is required to address safety issues for human health and determine the formulation to improve the insecticidal potency, stability and cost-benefit ratio.

Comparison of the Potency of Phenylephrine and Norepinephrine Bolus Doses Used to Treat Postspinal Hypotension During Elective Cesarean Section

(Int J Obst Anesth. 2019;38:25–31) Vasopressors to manage hypotension after spinal anesthesia are commonly used in obstetric patients. Phenylephrine has been considered the vasopressor of choice for many years, but it can result in reflex bradycardia and an associated fall in cardiac output. Norepinephrine is another potent vasopressor that has significant chronotropic effects that should limit bradycardia. However, there is little information about the preferred dose for managing postspinal hypotension in obstetric patients or its potency ratio compared with phenylephrine. This study aimed to calculate the 95% and 50% effective doses (ED95 and ED50) of both drugs and their potency ratio when administered as a bolus for the treatment of spinal-induced hypotension in women undergoing elective cesarean section.

Health effects of concurrent ambient and tobacco smoke-derived particle exposures at low concentrations in children with asthma.

Exposure to particulate matter less than 2.5 microns from either ambient pollution (AMB-PM2.5) or secondhand smoke (SHS-PM2.5) have been associated with asthma worsening, but there is little information on effects and relative potency with concurrent exposures. We studied health effects of concurrent exposures to AMB-PM2.5 and SHS-PM2.5 over a 6-year period in schoolchildren with asthma. Regression calibration with instrumental variables (RCIV) was utilized to estimate effects of personal exposure to low-level SHS and AMB-PM2.5 on daily albuterol usage and urinary leukotriene E4 (uLTE4; a biomarker of asthma-related inflammation) using urine cotinine and concentrations from fixed and personal pollution monitors. Each IQR increase in SHS-PM2.5 exposure was associated with a 6.7% increase (95% CI: 1.0-12.8%) in uLTE4 on the same day and 9.4% increase (95% CI: -2.6 to 22.7%) in albuterol use the next day, when children were co-exposed to mean levels of AMB-PM2.5. The dose-response relationship between health outcomes and one pollutant was higher at lower levels of the other pollutant. For example, at lower levels of predicted SHS-PM2.5 exposure, increases in health outcomes per IQR increase in AMB-PM2.5 ranged between 2 and 5%, but were negligible at higher SHS-PM2.5 levels. Comparing at equivalent co-exposure levels, SHS-PM2.5 was 1.6 times more potent than AMB-PM2.5 for uLTE4 (95% CI: 1.1-2.3); estimates for albuterol usage were similar but less significant. Effects at mean co-exposure levels were closer [SHS to AMB-PM2.5 potency ratio = 1.2 (95% CI: 0.9-1.5) for uLTE4 and 1.2 (95% CI: 0.7-1.9) for albuterol usage]. In summary, concurrent exposure to relatively low levels of SHS and AMB-PM2.5 were associated with health outcomes in asthmatic schoolchildren. Dose responses varied with changes in the relative amounts of each pollutant; SHS-PM2.5 was observed to be more potent than AMB-PM2.5 when co-exposure levels were equivalent.

Production of New F1 Hybrids Cucumber (Cucumis sativus, L.) in Open Field

This investigation was carried out at Kaha Vegetable Research Farm, Kalubia Governorate, Egypt 2015 and 2016 to study heterosis percentage over mid and better parents, potence ratio and correlation coefficient between traits for some important economical characters in cucumber. Five different parental lines of cucumber obtained from Cornell University which included parental line1380-1(P1); parental line87- 674-1(P2); parental line99-340(P3); parental line99-357(P4) and parental line99-347(P5) were carried out by 5 x 5 half diallel mating design, the experimental design was randomized complete block with three replicates. The obtained results generally that the utilized parental lines appeared to have wide ranges of diversity in the different studied traits and their indicated differences were found significant in the most situations. The results exhibited that the highest significant heterosis (47.30%) was reported for early yield per feddan(ton) followed by total yield per feddan (45.81%) and fruit shape index (40.78%), while the largest significant heterosis over better parent (33.97 and 32.86%) was recorded for early yield per feddan followed by (31.53 and 31.50% ) for total yieldThe results illustrated that plant length(cm) and number of leaves per plant exhibited significant and positive genotypic and phenotypic correlation with fruit length(cm), fruit shape index(cm), early yield per feddan(ton), average fruit weight(g), number of fruits per plant and total yield per feddan (ton). These positive correlations indicated that a selection programme based on any of these traits will be resulted in increasing yield. Negative and significant association was estimated with days to anthesis first female flower and fruit diameter(cm).

Gibberellins and Heterosis in Crops and Trees: An Integrative Review and Preliminary Study with Brassica.

Heterosis, or hybrid vigor, has contributed substantially to genetic improvements in crops and trees and its physiological basis involves multiple processes. Four associations with the phytohormone gibberellin (GA) indicate its involvement in the regulation of heterosis for shoot growth in maize, sorghum, wheat, rice, tomato and poplar. (1) Inbreds somewhat resemble GA-deficient dwarfs and are often highly responsive to exogenous GA3. (2) Levels of endogenous GAs, including the bioeffector GA1, its precursors GA19 and GA20, and/or its metabolite GA8, are higher in some fast-growing hybrids than parental genotypes. (3) Oxidative metabolism of applied [3H]GAs is more rapid in vigorous hybrids than inbreds, and (4) heterotic hybrids have displayed increased expression of GA biosynthetic genes including GA 20-oxidase and GA 3-oxidase. We further investigated Brassica rapa, an oilseed rape, by comparing two inbreds (AO533 and AO539) and their F1 hybrid. Seedling emergence was faster in the hybrid and potence ratios indicated dominance for increased leaf number, area and mass, and stem mass. Overdominance (heterosis) was displayed for root mass, leading to slight heterosis for total plant mass. Stem contents of GA19,20,1 were similar across the Brassica genotypes and increased prior to bolting; elongation was correlated with endogenous GA but heterosis for shoot growth was modest. The collective studies support a physiological role for GAs in the regulation of heterosis for shoot growth in crops and trees, and the Brassica study encourages further investigation of heterosis for root growth.

Allele-Selective Knockdown of MYH7 Using Antisense Oligonucleotides

Hundreds of dominant-negative myosin mutations have been identified that lead to hypertrophic cardiomyopathy, and the biomechanical link between mutation and disease is heterogeneous across this patient population. To increase the therapeutic feasibility of treating this diverse genetic population, we investigated the ability of locked nucleic acid (LNA)-modified antisense oligonucleotides (ASOs) to selectively knock down mutant myosin transcripts by targeting single-nucleotide polymorphisms (SNPs) that were found to be common in the myosin heavy chain 7 (MYH7) gene. We identified three SNPs in MYH7 and designed ASO libraries to selectively target either the reference or alternate MYH7 sequence. We identified ASOs that selectively knocked down either the reference or alternate allele at all three SNP regions. We also show allele-selective knockdown in a mouse model that was humanized on one allele. These results suggest that SNP-targeting ASOs are a promising therapeutic modality for treating cardiac pathology.