682 research outputs found
Do red deer stags (Cervus elaphus) use roar fundamental frequency (F0) to assess rivals?
It is well established that in humans, male voices are disproportionately lower pitched than female voices, and recent studies suggest that this dimorphism in fundamental frequency (F0) results from both intrasexual (male competition) and intersexual (female mate choice) selection for lower pitched voices in men. However, comparative investigations indicate that sexual dimorphism in F0 is not universal in terrestrial mammals. In the highly polygynous and sexually dimorphic Scottish red deer Cervus elaphus scoticus, more successful males give sexually-selected calls (roars) with higher minimum F0s, suggesting that high, rather than low F0s advertise quality in this subspecies. While playback experiments demonstrated that oestrous females prefer higher pitched roars, the potential role of roar F0 in male competition remains untested. Here we examined the response of rutting red deer stags to playbacks of re-synthesized male roars with different median F0s. Our results show that stags’ responses (latencies and durations of attention, vocal and approach responses) were not affected by the F0 of the roar. This suggests that intrasexual selection is unlikely to strongly influence the evolution of roar F0 in Scottish red deer stags, and illustrates how the F0 of terrestrial mammal vocal sexual signals may be subject to different selection pressures across species. Further investigations on species characterized by different F0 profiles are needed to provide a comparative background for evolutionary interpretations of sex differences in mammalian vocalizations
High sample throughput genotyping for estimating C-lineage introgression in the dark honeybee: an accurate and cost-effective SNP-based tool
The natural distribution of the honeybee (Apis mellifera L.) has been changed by humans in recent
decades to such an extent that the formerly widest-spread European subspecies, Apis mellifera
mellifera, is threatened by extinction through introgression from highly divergent commercial strains
in large tracts of its range. Conservation efforts for A. m. mellifera are underway in multiple European
countries requiring reliable and cost-efficient molecular tools to identify purebred colonies. Here, we
developed four ancestry-informative SNP assays for high sample throughput genotyping using the
iPLEX Mass Array system. Our customized assays were tested on DNA from individual and pooled,
haploid and diploid honeybee samples extracted from different tissues using a diverse range of
protocols. The assays had a high genotyping success rate and yielded accurate genotypes. Performance
assessed against whole-genome data showed that individual assays behaved well, although the
most accurate introgression estimates were obtained for the four assays combined (117 SNPs).
The best compromise between accuracy and genotyping costs was achieved when combining two
assays (62 SNPs). We provide a ready-to-use cost-effective tool for accurate molecular identification
and estimation oinfo:eu-repo/semantics/publishedVersio
Genetic control of resistance to salmonellosis and to Salmonella carrier-state in fowl: a review
<p>Abstract</p> <p>Salmonellosis is a frequent disease in poultry stocks, caused by several serotypes of the bacterial species <it>Salmonella enterica </it>and sometimes transmitted to humans through the consumption of contaminated meat or eggs. Symptom-free carriers of the bacteria contribute greatly to the propagation of the disease in poultry stocks. So far, several candidate genes and quantitative trait loci (QTL) for resistance to carrier state or to acute disease have been identified using artificial infection of <it>S. enterica </it>serovar Enteritidis or <it>S. enterica </it>serovar Typhimurium strains in diverse genetic backgrounds, with several different infection procedures and phenotypic assessment protocols. This diversity in experimental conditions has led to a complex sum of results, but allows a more complete description of the disease. Comparisons among studies show that genes controlling resistance to <it>Salmonella </it>differ according to the chicken line studied, the trait assessed and the chicken's age. The loci identified are located on 25 of the 38 chicken autosomal chromosomes. Some of these loci are clustered in several genomic regions, indicating the possibility of a common genetic control for different models. In particular, the genomic regions carrying the candidate genes <it>TLR4 </it>and <it>SLC11A1</it>, the Major Histocompatibility Complex (MHC) and the QTL <it>SAL1 </it>are interesting for more in-depth studies. This article reviews the main <it>Salmonella </it>infection models and chicken lines studied under a historical perspective and then the candidate genes and QTL identified so far.</p
On the thermodynamics of the Swift–Hohenberg theory
We present the microbalance including the microforces, the first- and second-order microstresses for the Swift–Hohenberg equation concomitantly with their constitutive equations, which are consistent with the free-energy imbalance. We provide an explicit form for the microstress structure for a free-energy functional endowed with second-order spatial derivatives. Additionally, we generalize the Swift–Hohenberg theory via a proper constitutive process. Finally, we present one highly resolved three-dimensional numerical simulation to demonstrate the particular form of the resulting microstresses and their interactions in the evolution of the Swift–Hohenberg equation
Meta-analysis of treatment outcomes for patients with m.11778G>A MT-ND4 Leber hereditary optic neuropathy
Our aim was to assess the visual outcomes of patients with Leber hereditary optic neuropathy (LHON) harboring the m.11778G>A MT-ND4 mutation who had no treatment (natural history) or received idebenone or lenadogene nolparvovec. Efficacy outcomes included clinically relevant recovery (CRR) from nadir and final best-corrected visual acuity (BCVA). For the natural history and idebenone groups, we performed a systematic review of the literature and available clinical/regulatory reports. For the lenadogene nolparvovec group, all data from phase 3 studies were included. The overall effect and its 95 % confidence interval (CI) were estimated using a random effects model. For each meta-analysis, patients had a mean age of approximately 30 years at vision loss and were mostly (≥78 %) men. The CRR from nadir [95 % CI] at eye level was 17 % [7 %; 30 %] (n=316 eyes), 31 % [24 %; 40 %] (n=313) and 59 % [54 %; 64 %] (n=348) in untreated, idebenone-treated and lenadogene nolparvovec-treated patients, respectively. This gradient of efficacy was also observed with CRR at the patient level and final BCVA. There was a gradient of efficacy in all assessed visual outcomes, more marked for CRR than for final BCVA, with lenadogene nolparvovec gene therapy superior to idebenone treatment, and both superior to the natural history of the disease
Open-Angle Glaucoma and Paraoptic Cyst: First Description of a Series of 11 Patients
International audienceWe report 11 patients who were referred to our institution for severe open-angle glaucoma who had a paraoptic cyst on MR imaging. All cysts were extraoptic and retrolaminar; most were deforming the adjacent optic nerve. Cysts had a high signal on T2 and FLAIR sequences, and a variable signal on T1 and variable echogenicity, suggesting different proteinaceous content. Arterial vascularization of the optic nerve was normal. Cyst volumes were inversely correlated with the severity of glaucoma on the same eye (P < .01-.05, Spearman correlation coefficient). We hypothesized that such cysts may reflect a valve mechanism, which would allow preservation of the translamina cribrosa pressure and thus could preserve visual function. The rarity of this association, together with the frequent mass effect of the cyst on the optic nerve, stresses the necessity of long-term follow-up in these patients
Long-Term Follow-Up After Unilateral Intravitreal Gene Therapy for Leber Hereditary Optic Neuropathy: The RESTORE Study
BACKGROUND: RESCUE and REVERSE were 2 Phase 3 clinical trials that assessed the efficacy and safety of intravitreal gene therapy with lenadogene nolparvovec (rAAV2/2-ND4) for the treatment of Leber hereditary optic neuropathy (LHON). RESTORE is the long-term follow-up study of subjects treated in the RESCUE and REVERSE trials. METHODS: In RESCUE and REVERSE, 76 subjects with LHON because of the m.11778 G>A mutation in the mitochondrial gene ND4 received a single unilateral intravitreal injection of lenadogene nolparvovec. After 96 weeks, 61 subjects were enrolled in the long-term follow-up study RESTORE. The best-corrected visual acuity (BCVA) was assessed over a period of up to 52 months after onset of vision loss. A locally estimated scatterplot smoothing regression model was used to analyze changes in BCVA over time. Vision-related quality of life was reported using the visual function questionnaire-25 (VFQ-25). RESULTS: The population of MT-ND4 subjects enrolled in RESTORE was representative of the combined cohorts of RESCUE and REVERSE for mean age (35.1 years) and gender distribution (79% males). There was a progressive and sustained improvement of BCVA up to 52 months after the onset of vision loss. The final mean BCVA was 1.26 logarithm of the minimal angle of resolution 48 months after the onset of vision loss. The mean VFQ-25 composite score increased by 7 points compared with baseline. CONCLUSION: The treatment effect of lenadogene nolparvovec on BCVA and vision-related quality of life observed 96 weeks (2 years) after treatment in RESCUE and REVERSE was sustained at 3 years in RESTORE, with a maximum follow-up of 52 months (4.3 years) after the onset of vision loss
Intravitreal Gene Therapy vs. Natural History in Patients With Leber Hereditary Optic Neuropathy Carrying the m.11778G>A ND4 Mutation: Systematic Review and Indirect Comparison
Objective: This work aimed to compare the evolution of visual outcomes in Leber hereditary optic neuropathy (LHON) patients treated with intravitreal gene therapy to the spontaneous evolution in prior natural history (NH) studies. Design: A combined analysis of two phase three randomized, double-masked, sham-controlled studies (REVERSE and RESCUE) and their joint long-term extension trial (CLIN06) evaluated the efficacy of rAAV2/2-ND4 vs. 11 pooled NH studies used as an external control. Subjects: The LHON subjects carried the m.11778G>A ND4 mutation and were aged ≥15 years at onset of vision loss. Methods: A total of 76 subjects received a single intravitreal rAAV2/2-ND4 injection in one eye and sham injection in the fellow eye within 1 year after vision loss in REVERSE and RESCUE. Both eyes were considered as treated due to the rAAV2/2-ND4 treatment efficacy observed in the contralateral eyes. Best corrected visual acuity (BCVA) from REVERSE, RESCUE, and CLIN06 up to 4.3 years after vision loss was compared to the visual acuity of 208 NH subjects matched for age and ND4 genotype. The NH subjects were from a LHON registry (REALITY) and from 10 NH studies. A locally estimated scatterplot smoothing (LOESS), non-parametric, local regression model was used to modelize visual acuity curves over time, and linear mixed model was used for statistical inferences. Main Outcome Measures: The main outcome measure was evolution of visual acuity from 12 months after vision loss, when REVERSE and RESCUE patients had been treated with rAAV2/2-ND4. Results: The LOESS curves showed that the BCVA of the treated patients progressively improved from month 12 to 52 after vision loss. At month 48, there was a statistically and clinically relevant difference in visual acuity of −0.33 logarithm of the minimal angle of resolution (LogMAR) (16.5 ETDRS letters equivalent) in favor of treated eyes vs. NH eyes (p A LHON patients treated with rAAV2/2-ND4 exhibited an improvement of visual acuity over more than 4 years after vision loss to a degree not demonstrated in NH studies. Clinical Trial Registration: NCT02652767, NCT02652780, NCT03406104, and NCT03295071
Intravitreal Gene Therapy vs. Natural History in Patients With Leber Hereditary Optic Neuropathy Carrying the m.11778G>A ND4 Mutation: Systematic Review and Indirect Comparison
Objective: This work aimed to compare the evolution of visual outcomes in Leber hereditary optic neuropathy (LHON) patients treated with intravitreal gene therapy to the spontaneous evolution in prior natural history (NH) studies. Design: A combined analysis of two phase three randomized, double-masked, sham-controlled studies (REVERSE and RESCUE) and their joint long-term extension trial (CLIN06) evaluated the efficacy of rAAV2/2-ND4 vs. 11 pooled NH studies used as an external control. Subjects: The LHON subjects carried the m.11778G>A ND4 mutation and were aged ≥15 years at onset of vision loss. Methods: A total of 76 subjects received a single intravitreal rAAV2/2-ND4 injection in one eye and sham injection in the fellow eye within 1 year after vision loss in REVERSE and RESCUE. Both eyes were considered as treated due to the rAAV2/2-ND4 treatment efficacy observed in the contralateral eyes. Best corrected visual acuity (BCVA) from REVERSE, RESCUE, and CLIN06 up to 4.3 years after vision loss was compared to the visual acuity of 208 NH subjects matched for age and ND4 genotype. The NH subjects were from a LHON registry (REALITY) and from 10 NH studies. A locally estimated scatterplot smoothing (LOESS), non-parametric, local regression model was used to modelize visual acuity curves over time, and linear mixed model was used for statistical inferences. Main Outcome Measures: The main outcome measure was evolution of visual acuity from 12 months after vision loss, when REVERSE and RESCUE patients had been treated with rAAV2/2-ND4. Results: The LOESS curves showed that the BCVA of the treated patients progressively improved from month 12 to 52 after vision loss. At month 48, there was a statistically and clinically relevant difference in visual acuity of −0.33 logarithm of the minimal angle of resolution (LogMAR) (16.5 ETDRS letters equivalent) in favor of treated eyes vs. NH eyes (p < 0.01). Most treated eyes (88.7%) were on-chart at month 48 as compared to 48.1% of the NH eyes (p < 0.01). The treatment effect at last observation remained statistically and clinically significant when adjusted for age and duration of follow-up (−0.32 LogMAR, p < 0.0001). Conclusions: The m.11778G>A LHON patients treated with rAAV2/2-ND4 exhibited an improvement of visual acuity over more than 4 years after vision loss to a degree not demonstrated in NH studies. Clinical Trial Registration: NCT02652767, NCT02652780, NCT03406104, and NCT03295071
Nerve excitability changes related to muscle weakness in chronic progressive external ophthalmoplegia
Objective:
To explore potential spreading to peripheral nerves of the mitochondrial dysfunction in chronic progressive external ophthalmoplegia (CPEO) by assessing axonal excitability.
Methods:
CPEO patients (n = 13) with large size deletion of mitochondrial DNA and matching healthy controls (n = 22) were included in a case-control study. Muscle strength was quantified using MRC sum-score and used to define two groups of patients: CPEO-weak and CPEO-normal (normal strength). Nerve excitability properties of median motor axons were assessed with the TROND protocol and changes interpreted with the aid of a model.
Results:
Alterations of nerve excitability strongly correlated with scores of muscle strength. CPEO-weak displayed abnormal nerve excitability compared to CPEO-normal and healthy controls, with increased superexcitability and responses to hyperpolarizing current. Modeling indicated that the CPEO-weak recordings were best explained by an increase in the ‘Barrett-Barrett’ conductance across the myelin sheath.
Conclusion:
CPEO patients with skeletal weakness presented sub-clinical nerve excitability changes, which were not consistent with axonal membrane depolarization, but suggested Schwann cell involvement.
Significance:
This study provides new insights into the spreading of large size deletion of mitochondrial DNA to Schwann cells in CPEO patients
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