Sex in Oreochromis niloticus (Nile tilapia) is principally determined by an XX/XY locus but other genetic and environmental factors also influence sex ratio. Restriction Associated DNA (RAD) ...sequencing was used in two families derived from crossing XY males with females from an isogenic clonal line, in order to identify Single Nucleotide Polymorphisms (SNPs) and map the sex-determining region(s). We constructed a linkage map with 3,802 SNPs, which corresponded to 3,280 informative markers, and identified a major sex-determining region on linkage group 1, explaining nearly 96% of the phenotypic variance. This sex-determining region was mapped in a 2 cM interval, corresponding to approximately 1.2 Mb in the O. niloticus draft genome. In order to validate this, a diverse family (4 families; 96 individuals in total) and population (40 broodstock individuals) test panel were genotyped for five of the SNPs showing the highest association with phenotypic sex. From the expanded data set, SNPs Oni23063 and Oni28137 showed the highest association, which persisted both in the case of family and population data. Across the entire dataset all females were found to be homozygous for these two SNPs. Males were heterozygous, with the exception of five individuals in the population and two in the family dataset. These fish possessed the homozygous genotype expected of females. Progeny sex ratios (over 95% females) from two of the males with the "female" genotype indicated that they were neomales (XX males). Sex reversal induced by elevated temperature during sexual differentiation also resulted in phenotypic males with the "female" genotype. This study narrows down the region containing the main sex-determining locus, and provides genetic markers tightly linked to this locus, with an association that persisted across the population. These markers will be of use in refining the production of genetically male O. niloticus for aquaculture.
Atlantic halibut (Hippoglossus hippoglossus) is a high-value, niche market species for cold-water marine aquaculture. Production of monosex female stocks is desirable in commercial production since ...females grow faster and mature later than males. Understanding the sex determination mechanism and developing sex-associated markers will shorten the time for the development of monosex female production, thus decreasing the costs of farming.
Halibut juveniles were masculinised with 17 α-methyldihydrotestosterone (MDHT) and grown to maturity. Progeny groups from four treated males were reared and sexed. Two of these groups (n = 26 and 70) consisted of only females, while the other two (n = 30 and 71) contained balanced sex ratios (50% and 48% females respectively). DNA from parents and offspring from the two mixed-sex families were used as a template for Restriction-site Associated DNA (RAD) sequencing. The 648 million raw reads produced 90,105 unique RAD-tags. A linkage map was constructed based on 5703 Single Nucleotide Polymorphism (SNP) markers and 7 microsatellites consisting of 24 linkage groups, which corresponds to the number of chromosome pairs in this species. A major sex determining locus was mapped to linkage group 13 in both families. Assays for 10 SNPs with significant association with phenotypic sex were tested in both population data and in 3 additional families. Using a variety of machine-learning algorithms 97% correct classification could be obtained with the 3% of errors being phenotypic males predicted to be females.
Altogether our findings support the hypothesis that the Atlantic halibut has an XX/XY sex determination system. Assays are described for sex-associated DNA markers developed from the RAD sequencing analysis to fast track progeny testing and implement monosex female halibut production for an immediate improvement in productivity. These should also help to speed up the inclusion of neomales derived from many families to maintain a larger effective population size and ensure long-term improvement through selective breeding.
It is challenging to estimate a true prevalence of hidradenitis suppurativa (HS) because it is underdiagnosed and misdiagnosed. Prevalences have been reported from 0.00033% to 4.1%. The incidence ...seems to be rising. In addition to dermatologic symptoms, HS is associated with metabolic syndrome, and increased cardiovascular risk. The majority of HS patients are smokers. Additional somatic comorbidities complicating HS include autoimmune conditions, follicular syndromes, rheumatologic conditions, and malignancies. HS patients are troubled by psychological comorbidities. When treating HS patients it is imperative not only to treat the skin symptoms, but also address the screening and treatment of possible comorbidities.
Submaximal eccentric (ECC) cycling exercise is commonly used in research studies. No previous study has specified the required time naïve participants take to familiarize with submaximal ECC cycling. ...Therefore, we designed this study to determine whether critical indicators of cycling reliability and variability stabilize during 15 min of submaximal, semi-recumbent ECC cycling (ECC cycling). Twenty-two participants, aged between 18–51 years, volunteered to complete a single experimental session. Each participant completed three peak eccentric torque protocol (PETP) tests, nine countermovement jumps and 15 min of submaximal (i.e., 10% peak power output produced during the PETP tests) ECC cycling. Muscle activation patterns were recorded from six muscles (rectus femoris, RF; vastus lateralis, VL; vastus medialis, VM; soleus, SOL; medial gastrocnemius, GM; tibialis anterior, TA), during prescribed-intensity ECC cycling, using electromyography (EMG). Minute-to-minute changes in the reliability and variability of EMG patterns were examined using intra-class correlation coefficient (ICC) and variance ratios (VR). Differences between target and actual power output were also used as an indicator of familiarization. Activation patterns for 4/6 muscles (RF, VL, VM and GM) became more consistent over the session, the RF, VL and VM increasing from moderate (ICC = 0.5–0.75) to good (ICC = 0.75–0.9) reliability by the 11th minute of cycling and the GM good reliability from the 1st minute (ICC = 0.79, ICC range = 0.70–0.88). Low variability (VR ≤ 0.40) was maintained for VL, VM and GM from the 8th, 8th and 1st minutes, respectively. We also observed a significant decrease in the difference between actual and target power output (χ
2
14
= 30.895,
p
= 0.006,
W
= 0.105), expressed primarily between the 2nd and 3rd minute of cycling (
Z
= -2.677,
p
= 0.007). Indicators of familiarization during ECC cycling, including deviations from target power output levels and the reliability and variability of muscle activation patterns stabilized within 15 min of cycling. Based upon this data, it would be reasonable for future studies to allocate ∼ 15 min to familiarize naïve participants with a submaximal ECC cycling protocol.
Maintenance of upright standing posture has often been explained using the inverted pendulum model. This model considers the ankle plantarflexors to act as a single synergistic group. There are ...differences in muscle properties among the medial and lateral gastrocnemius (MG and LG, respectively) and the soleus that may affect their activation. Twelve volunteers participated in an investigation to determine whether the activation of the ankle plantarflexor muscles was modulated according to perturbation direction during unilateral standing perturbations of 1% body mass. High-density surface electromyography (HDS-EMG) was used to determine the amplitude and barycenter of the muscle activation and kinematic analysis was used to evaluate ankle, knee, and hip joint movement. The HDS-EMG amplitude and barycenter of MG and LG were modulated with the perturbation direction (MG
p
< 0.05; LG
p
< 0.01; one-way repeated-measures ANOVA). In soleus, the HDS-EMG barycenter modulated across the perturbation direction (
p
< 0.01 for X&Y coordinates), but the HDS-EMG amplitude did not change. A repeated-measures correlation was used to interpret the HDS-EMG pattern in the context of the kinematics. The relative contribution of MG activation compared to the total gastrocnemii activation was significantly associated with ankle dorsi/plantarflexion (
r
rm
= 0.620), knee flexion/extension and abduction/adduction (
r
rm
= 0.622 and
r
rm
= 0.547, respectively), and hip flexion/extension and abduction/adduction (
r
rm
= 0.653 and
r
rm
= 0.432, respectively). The findings suggest that the central nervous system activates motor units within different regions of MG, LG and SOL in response to standing perturbations in different directions.
Phosphorus cardiovascular magnetic resonance spectroscopy (31P-CMRS) has emerged as an important tool for the preclinical assessment of myocardial energetics in vivo. However, the high rate and ...diminutive size of the mouse heart is a challenge, resulting in low resolution and poor signal-to-noise. Here we describe a refined high-resolution 31P-CMRS technique and apply it to a novel double transgenic mouse (dTg) with elevated myocardial creatine and creatine kinase (CK) activity. We hypothesised a synergistic effect to augment energetic status, evidenced by an increase in the ratio of phosphocreatine-to-adenosine-triphosphate (PCr/ATP).
Single transgenic Creatine Transporter overexpressing (CrT-OE, n = 7) and dTg mice (CrT-OE and CK, n = 6) mice were anaesthetised with isoflurane to acquire 31P-CMRS measurements of the left ventricle (LV) utilising a two-dimensional (2D), threefold under-sampled density-weighted chemical shift imaging (2D-CSI) sequence, which provided high-resolution data with nominal voxel size of 8.5 µl within 70 min. (1H-) cine-CMR data for cardiac function assessment were obtained in the same imaging session. Under a separate examination, mice received invasive haemodynamic assessment, after which tissue was collected for biochemical analysis. Myocardial creatine levels were elevated in all mouse hearts, but only dTg exhibited significantly elevated CK activity, resulting in a 51% higher PCr/ATP ratio in heart (3.01 ± 0.96 vs. 2.04 ± 0.57—mean ± SD; dTg vs. CrT-OE), that was absent from adjacent skeletal muscle. No significant differences were observed for any parameters of LV structure and function, confirming that augmentation of CK activity does not have unforeseen consequences for the heart.
We have developed an improved 31P-CMRS methodology for the in vivo assessment of energetics in the murine heart which enabled high-resolution imaging within acceptable scan times. Mice over-expressing both creatine and CK in the heart exhibited a synergistic elevation in PCr/ATP that can now be tested for therapeutic potential in models of chronic heart failure.
The potential synergy between interleukin-12 (IL-12) and IL-15 holds promise for more effective solid tumor immunotherapy. Nevertheless, previous clinical trials involving therapeutic cytokines have ...encountered obstacles such as short pharmacokinetics, limited tumor microenvironment (TME) targeting, and substantial systemic toxicity.
To address these challenges, we fused single-chain human IL-12 and native human IL-15 in
onto a fully human albumin binding (F
AB) domain single-chain antibody fragment (scFv). This novel fusion protein, IL12-F
AB-IL15 (SON-1210), is anticipated to amplify the therapeutic impact of interleukins and combination immunotherapies in human TME. The molecule was studied
and in animal models to assess its pharmacokinetics, potency, functional characteristics, safety, immune response, and efficacy.
SON-1210 demonstrated robust binding affinity to albumin and exhibited the anticipated
activity and tumor model efficacy that might be expected based on decades of research on native IL-12 and IL-15. Notably, in the B16F10 melanoma model (a non-immunogenic, relatively "cold" tumor), the murine counterpart of the construct, which had mouse (m) and human (h) cytokine sequences for the respective payloads (mIL12-F
AB-hIL15), outperformed equimolar doses of the co-administered native cytokines in a dose-dependent manner. A single dose caused a marked reduction in tumor growth that was concomitant with increased IFNγ levels; increased Th1, CTL, and activated NK cells; a shift in macrophages from the M2 to M1 phenotype; and a reduction in Treg cells. In addition, a repeat-dose non-human primate (NHP) toxicology study displayed excellent tolerability up to 62.5 µg/kg of SON-1210 administered three times, which was accompanied by the anticipated increases in IFNγ levels. Toxicokinetic analyses showed sustained serum levels of SON-1210, using a sandwich ELISA with anti-IL-15 for capture and biotinylated anti-IL-12 for detection, along with sustained IFNγ levels, indicating prolonged kinetics and biological activity.
Collectively, these findings support the suitability of SON-1210 for patient trials in terms of activity, efficacy, and safety, offering a promising opportunity for solid tumor immunotherapy. Linking cytokine payloads to a fully human albumin binding domain provides an indirect opportunity to target the TME using potent cytokines in
that can redirect the immune response and control tumor growth.
Gilthead seabream (
Sparus aurata) is one of the most important species among intensively reared fish in the Mediterranean region. Although there is a considerable interest in the genetic improvement ...of this species, many of the genetic parameters of commercial stocks have yet to be investigated. The effective population size (
N
e) of a commercial gilthead seabream broodstock was determined using microsatellite analysis. Eight microsatellite loci were used to ensure a high confidence to the parental assignment of offspring from several mass-spawning events. The
N
e was consistently low, ranging from 14 to 18, between photoperiod-controlled broodstock groups. This equated to an inbreeding rate of 2.7–3.5% per generation. The primary constraint on
N
e was the high variance in family size and fewer males than females contributing to each spawning. The contribution of male parents to spawning was also more variable than females. Log-linear modelling of offspring counts revealed a significant quadratic relationship, with intermediate parental weights being optimum. The relationship between parental weight and contribution may be evidence of an optimum age structure to the broodstock, or stabilising selection. Low
N
e in commercial stocks of gilthead seabream could lead to an increased risk of inbreeding through the practice of broodstock replacement from within same-farm populations.
Tilapias (family Cichlidae) are of importance in aquaculture and fisheries. Hybridisation and introgression are common within tilapia genera but are difficult to analyse due to limited numbers of ...species-specific genetic markers. We tested the potential of double digested restriction-site associated DNA (ddRAD) sequencing for discovering single nucleotide polymorphism (SNP) markers to distinguish between 10 tilapia species. Analysis of ddRAD data revealed 1,371 shared SNPs in the de novo-based analysis and 1,204 SNPs in the reference-based analysis. Phylogenetic trees based on these two analyses were very similar. A total of 57 species-specific SNP markers were found among the samples analysed of the 10 tilapia species. Another set of 62 species-specific SNP markers was identified from a subset of four species which have often been involved in hybridisation in aquaculture: 13 for Oreochromis niloticus, 23 for O. aureus, 12 for O. mossambicus and 14 for O. u. hornorum. A panel of 24 SNPs was selected to distinguish among these four species and validated using 91 individuals. Larger numbers of SNP markers were found that could distinguish between the pairs of species within this subset. This technique offers potential for the investigation of hybridisation and introgression among tilapia species in aquaculture and in wild populations.
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