Mitochondrial oxidative phosphorylation in autosomal dominant optic atrophy

<p>Abstract</p> <p>Background</p> <p>Autosomal dominant optic atrophy (ADOA), a form of progressive bilateral blindness due to loss of retinal ganglion cells and optic nerve deterioration, arises predominantly from mutations in the nuclear gene for the mitochondrial GTPase, OPA1. OPA1 localizes to mitochondrial cristae in the inner membrane where electron transport chain complexes are enriched. While OPA1 has been characterized for its role in mitochondrial cristae structure and organelle fusion, possible effects of OPA1 on mitochondrial function have not been determined.</p> <p>Results</p> <p>Mitochondria from six ADOA patients bearing <it>OPA1 </it>mutations and ten ADOA patients with unidentified gene mutations were studied for respiratory capacity and electron transport complex function. Results suggest that the nuclear DNA mutations that give rise to ADOA in our patient population do not alter mitochondrial electron transport.</p> <p>Conclusion</p> <p>We conclude that the pathophysiology of ADOA likely stems from the role of OPA1 in mitochondrial structure or fusion and not from OPA1 support of oxidative phosphorylation.</p

Biodistribution of intravitreal lenadogene nolparvovec gene therapy in nonhuman primates.

Lenadogene nolparvovec (Lumevoq) gene therapy was developed to treat Leber hereditary optic neuropathy (LHON) caused by the m.11778G > A in MT-ND4 that affects complex I of the mitochondrial respiratory chain. Lenadogene nolparvovec is a replication-defective, single-stranded DNA recombinant adeno-associated virus vector 2 serotype 2, containing a codon-optimized complementary DNA encoding the human wild-type MT-ND4 subunit protein. Lenadogene nolparvovec was administered by unilateral intravitreal injection in MT-ND4 LHON patients in two randomized, double-masked, and sham-controlled phase III clinical trials (REVERSE and RESCUE), resulting in bilateral improvement of visual acuity. These and other earlier results suggest that lenadogene nolparvovec may travel from the treated to the untreated eye. To investigate this possibility further, lenadogene nolparvovec was unilaterally injected into the vitreous body of the right eye of healthy, nonhuman primates. Viral vector DNA was quantifiable in all eye and optic nerve tissues of the injected eye and was detected at lower levels in some tissues of the contralateral, noninjected eye, and optic projections, at 3 and 6 months after injection. The results suggest that lenadogene nolparvovec transfers from the injected to the noninjected eye, thus providing a potential explanation for the bilateral improvement of visual function observed in the LHON patients

Early blood pressure, antihypotensive therapy and outcomes at 18–22 months’ corrected age in extremely preterm infants

Investigate relationships between early blood pressure (BP) changes, receipt of anti-hypotensive therapy, and 18 – 22 month corrected age (CA) outcomes for extremely preterm infants

Comprehensive extraction method integrated with NMR metabolomics: a new bioactivity screening method for plants, adenosine A1 receptor binding compounds in Orthosiphon stamineus benth

A large number of plant metabolites has provided as an incomparable chemical source for drug development. However, the wide range of the polarity of metabolites has been a big obstacle for full use of the chemical diversity. The initial step conventional extraction method by a single solvent does not make use of all the metabolites contained in plants. Also, it takes a long time to confirm the target activity of a single compound because of tedious separation steps. To solve the problem, a new extraction method coupled to NMR-based metabolomics is applied to identify bioactive natural products. A comprehensive extraction method consisting of a continuous flow of solvent mixtures through plant material was developed to provide extracts with a wider chemical variety than those yielded with a single solvent extraction. As the model experiment, 1H NMR spectra of the extracts obtained from the comprehensive extraction of Orthosiphon stamineus were subjected to multivariate data analysis to find its adenosine A1 binding activity. On the basis of the results, two flavonoids from a large number of chemicals were clearly verified to show the adenosine A1 binding activity without any further purification steps. This method could provide a solution to the major drawbacks of natural products in drug development

Patient Harm Due to Diagnostic Error of Neuro-Ophthalmologic Conditions

PURPOSE: To prospectively examine diagnostic error of neuro-ophthalmic conditions and resultant harm at multiple sites. DESIGN: Prospective, cross-sectional study. PARTICIPANTS: A total of 496 consecutive adult new patients seen at 3 university-based neuro-ophthalmology clinics in the United States in 2019 to 2020. METHODS: Collected data regarding demographics, prior care, referral diagnosis, final diagnosis, diagnostic testing, treatment, patient disposition, and impact of the neuro-ophthalmologic encounter. For misdiagnosed patients, we identified the cause of error using the Diagnosis Error Evaluation and Research (DEER) taxonomy tool and whether the patient experienced harm due to the misdiagnosis. MAIN OUTCOME MEASURES: The primary outcome was whether patients who were misdiagnosed before neuro-ophthalmology referral experienced harm as a result of the misdiagnosis. Secondary outcomes included appropriateness of referrals, misdiagnosis rate, interventions undergone before referral, and the primary type of diagnostic error. RESULTS: Referral diagnosis was incorrect in 49% of cases. A total of 26% of misdiagnosed patients experienced harm, which could have been prevented by earlier referral to neuro-ophthalmology in 97%. Patients experienced inappropriate laboratory testing, diagnostic imaging, or treatment before referral in 23%, with higher rates for patients misdiagnosed before referral (34% of patients vs. 13% with a correct referral diagnosis, P < 0.0001). Seventy-six percent of inappropriate referrals were misdiagnosed, compared with 45% of appropriate referrals (P < 0.0001). The most common reasons for referral were optic neuritis or optic neuropathy (21%), papilledema (18%), diplopia or cranial nerve palsies (16%), and unspecified vision loss (11%). The most common sources of diagnostic error were the physical examination (36%), generation of a complete differential diagnosis (24%), history taking (24%), and use or interpretation of diagnostic testing (13%). In 489 of 496 patients (99%), neuro-ophthalmology consultation (NOC) affected patient care. In 2% of cases, neuro-ophthalmology directly saved the patient's life or vision; in an additional 10%, harmful treatment was avoided or appropriate urgent referral was provided; and in an additional 48%, neuro-ophthalmology provided a diagnosis and direction to the patient's care. CONCLUSIONS: Misdiagnosis of neuro-ophthalmic conditions, mismanagement before referral, and preventable harm are common. Early appropriate referral to neuro-ophthalmology may prevent patient harm

Effect of thyroid hormone therapy on fatigability in older adults with subclinical hypothyroidism: a nested study within a randomized placebo-controlled trial

Background: Fatigue often triggers screening for and treatment of subclinical hypothyroidism. However, data on the impact of levothyroxine on fatigue is limited and previous studies might not have captured all aspects of fatigue. Method: This study is nested within the randomized, placebo-controlled, multicenter TRUST trial, including community-dwelling participants aged ≥65 and older, with persistent subclinical hypothyroidism (TSH 4.60–19.99 mIU/L, normal free thyroxine levels) from Switzerland and Ireland. Interventions consisted of daily levothyroxine starting with 50 μg (25 μg if weight &lt;50 kg or known coronary heart diseases) together with dose adjustments to achieve a normal TSH and mock titration in the placebo group. Main outcome was the change in physical and mental fatigability using the Pittsburgh Fatigability Scale over 1 year, assessed through multivariable linear regression with adjustment for country, sex, and levothyroxine starting dose. Results: Among 230 participants, the mean ± standard deviation (SD) TSH was 6.2 ± 1.9 mIU/L at baseline and decreased to 3.1 ± 1.3 with LT4 (n = 119) versus 5.3 ± 2.3 with placebo (n = 111, p &lt; .001) after 1 year. After adjustment we found no between-group difference at 1 year on perceived physical (0.2; 95% CI −1.8 to 2.1; p = .88), or mental fatigability (−1.0; 95% CI −2.8 to 0.8; p = .26). In participants with higher fatigability at baseline (≥15 points for the physical score [n = 88] or ≥13 points for the mental score [n = 41]), the adjusted between-group differences at 1 year were 0.4 (95% CI −3.6 to 2.8, p = .79) and −2.2 (95% CI −8.8 to 4.5, p = .51). Conclusions: Levothyroxine in older adults with mild subclinical hypothyroidism provides no change in physical or mental fatigability

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

Bilateral Visual Improvement with Unilateral Gene Therapy Injection for Leber Hereditary Optic Neuropathy

REVERSE is a randomized, double-masked, sham-controlled, multicenter, phase III clinical trial that evaluated the efficacy of a single intravitreal injection of rAAV2/2 ND4 in subjects with visual loss from Leber hereditary optic neuropathy (LHON). A total of 37 subjects carrying the m.11778G>A (MT-ND4) mutation and with duration of vision loss between 6 to 12 months were treated. Each subject’s right eye was randomly assigned in a 1:1 ratio to treatment with rAAV2/2 ND4 (GS010) or sham injection. The left eye received the treatment not allocated to the right eye. Unexpectedly, sustained visual improvement was observed in both eyes over the 96-week follow-up period. At Week 96, rAAV2/2 ND4-treated eyes showed a mean improvement in best-corrected visual acuity (BCVA) of -0.308 LogMAR (+15 ETDRS letters). A mean improvement of 0.259 (0.068) LogMAR (+13 ETDRS letters) was observed in the sham treated eyes. Consequently, the primary endpoint, defined as the difference in the change in BCVA from baseline to Week 48 between the two treatment groups, was not met (p = 0.894, ANCOVA). At Week 96, 25 subjects (68%) had a clinically relevant recovery in BCVA from baseline in at least one eye and 29 subjects (78%) had an improvement in vision in both eyes. A non-human primate study was conducted to investigate this bilateral improvement. Evidence of transfer of viral vector DNA from the injected eye to the anterior segment, retina and optic nerve of the contralateral non-injected eye supports a plausible mechanistic explanation for the unexpected bilateral improvement in visual function after unilateral injection

Typha (Cattail) Invasion in North American Wetlands: Biology, Regional Problems, Impacts, Ecosystem Services, and Management

Typha is an iconic wetland plant found worldwide. Hybridization and anthropogenic disturbances have resulted in large increases in Typha abundance in wetland ecosystems throughout North America at a cost to native floral and faunal biodiversity. As demonstrated by three regional case studies, Typha is capable of rapidly colonizing habitats and forming monodominant vegetation stands due to traits such as robust size, rapid growth rate, and rhizomatic expansion. Increased nutrient inputs into wetlands and altered hydrologic regimes are among the principal anthropogenic drivers of Typha invasion. Typha is associated with a wide range of negative ecological impacts to wetland and agricultural systems, but also is linked with a variety of ecosystem services such as bioremediation and provisioning of biomass, as well as an assortment of traditional cultural uses. Numerous physical, chemical, and hydrologic control methods are used to manage invasive Typha, but results are inconsistent and multiple methods and repeated treatments often are required. While this review focuses on invasive Typha in North America, the literature cited comes from research on Typha and other invasive species from around the world. As such, many of the underlying concepts in this review are relevant to invasive species in other wetland ecosystems worldwide