Plasma exchange for acute optic neuritis in neuromyelitis optica or neuromyelitis optica spectrum disorder: a systematic review.

OBJECTIVES: To appraise whether plasma exchange (PLEX) effectively improves visual function for acute optic neuritis (ON) in neuromyelitis optica (NMO) or neuromyelitis optica spectrum disorder (NMOSD). METHODS AND ANALYSIS: We searched Medline, Embase, Cochrane Library, ProQuest Central, and Web of Science to identify relevant articles published between 2006 and 2020.Eligible studies were in English and evaluated visual outcomes for people with acute ON in NMO or NMOSD treated with PLEX. They also had adequate pre- and posttreatment data. Excluded were studies with 1 or 2 case reports, or incomplete data. RESULTS: Twelve studies were qualitatively synthesized (1 RCT; 1 controlled NRSI; 10 observational studies). Five before-and-after observational studies were used for quantitative synthesis. The PLEX in the 5 studies (3 to 7 cycles over 2 to 3 weeks) was performed as second-line or adjunctive therapy for acute ON in NMO/NMOSD.The qualitative synthesis revealed that visual-acuity recovery occurred between one day and 6 months after the first PLEX cycle completion. Thirty-two of 48 participants in the 5 quantitative-synthesis studies received PLEX. Relative to pre-PLEX values, visual-acuity improvements were nonsignificant at these post-PLEX time points: 1 day (SMD 0.611; 95% CI -0.620 to 1.842); 2 weeks (SMD 0.0214; 95% CI -1.250 to 1.293); 3 months (SMD 1.014; 95% CI -0.954 to 2.982); and 6 months (SMD 0.450; 95% CI -2.643 to 3.543). CONCLUSIONS: There were inadequate data to determine whether PLEX effectively treats acute ON in NMO/NMOSD.

Aggregate current data of this systematic review is insufficient to definitively conclude whether therapeutic PLEX is effective in improving VA in cases of NMO or NMOSD.

Health-related quality of life of daily-life-affected benign essential blepharospasm: Multi-center observational study.

PURPOSE: To compare Thais' health-related quality of life (HRQOL) and severity grading, efficacy and safety in daily-life-affected benign essential blepharospasm (BEB) patients at baseline and after Botulinum toxin type A (BTX-A) treatment. DESIGN: Prospective-observational study. PARTICIPANTS: BEB patients with Jankovic rating scale (JRS) at least 3 in both severity and frequency graded from 14 institutes nationwide were included from August 2020 to June 2021. METHODS: Demographic data, HRQOL evaluated by the Thai version of EQ-5D-5L and NEI-VFQ-25 questionnaires, and severity grading score evaluated by Jankovic rating scale (JRS) at baseline, 1, and 3 months after the treatment were collected. The impact of the BTX-A injections and their complications were recorded. RESULTS: 184 daily-life-affected BEB patients were enrolled; 159 patients (86.4%) had complete data with a mean age of 61.40±10.09 years. About 88.05% were female, and 10.1% were newly diagnosed. Most of the patients had bilateral involvement (96.9%) and 12.6% had history of BEB-related accident. After BTX-A treatment, HRQOL improved significantly in 4 dimensions of EQ-5D-5L, except self-care. The EQ_VAS (mean±SD) was 64.54±19.27, 75.13±15.37, 73.8±15.85 (p<0.001) and EQ-5D-5L utility score was 0.748±0.23, 0.824±0.19 and 0.807±0.19 at baseline, 1, 3 months after treatment, respectively. From NEI-VFQ-25, HRQOL also improved in all dimensions, except eye pain. The JRS improved in all patients. Self-reported minor adverse events were 22.6%, which mostly resolved within the first month. CONCLUSION: Daily-life-affected BEB impacted HRQOL in most dimensions from both generic and visual-specific questionnaires. BTX-A treatment not only decreased disease severity, but also improved quality of life.

The epidemiology and mutation types of Leber's hereditary optic neuropathy in Thailand.

PURPOSE: Leber's hereditary optic neuropathy (LHON), the most common mitochondrial optic neuropathy, causes visual loss, especially in young adults. Due to the absence of epidemiological data in Southeast Asia, we aimed to determine Thai LHON patients' characteristics (demographic data, mutation types, and prognoses) as the first study in this region. METHODS: This retrospective chart review enrolled all Thai LHON patients confirmed by three mitochondrial DNA mutations (G11778A, T14484C, and G3460A) between January 1997 and December 2016. Patients with more than one year of follow-up were included in a visual progression analysis. The Mann-Whitney U-test was applied to compare groups, and prognosis-associated factors were analysed with the generalized estimating equation. RESULTS: In all, 229 patients were enrolled, with only nineteen females. Most mutations were of the G11778A type (91%), with T14484C accounting for the remainder. The age at onset of G11778A (21.9 years; interquartile range [IQR] 14.9, 33.5) was younger than that of T14484C (33.0 years; IQR 19.4, 37.5). Of 45 patients, the T14484C group demonstrated good vision recovery, whereas the G11778A group did not improve (difference in logMAR -0.7 and IQR -1.5, -0.2 versus logMAR 0.0 and IQR -0.3, 0.2, respectively; P value .001). The G11778A mutation, male, and older age were related to poor prognoses. CONCLUSIONS: The leading mutation in Thai LHON patients is the G11778A missense, followed by T14484C, while G3460A was not detected. The vast majority of patients were young adult males. The G11778A mutation, older age, and male gender are associated with poor vision outcomes. Key messageThe G11778A missense mutation is the most common among Thai LHON patients, followed by T14484C, while G3460A was not found. The G11778A mutation, older age, and male gender are associated with poor vision outcomes.

Structural and functional differentiation between compressive and glaucomatous optic neuropathy.

Clinical diagnoses of slow, progressive, painless visual losses with various degrees of visual field (VF) losses and disc atrophy are often confused between suprasellar compressive optic neuropathy (CON) and open-angle glaucomatous optic neuropathy (GON). We plotted the thickness of the peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell-inner plexiform layer (GCIPL) against the mean deviation (MD) of the VF of 34 eyes of CON at diagnosis, 30 eyes of CON after therapy, 29 eyes of GON, and 60 eyes of healthy controls in a cross-sectional investigation. At diagnosis, a disproportionally early pattern of structural thinning compared with the corresponding VF losses was unique to CON. GON- and CON-specific thinning parameters were generally useful in differentiating GON and CON from moderate to severe MD losses, but early MD losses (0 to - 6 dB) overlapped with GON in a CON-stage specific manner. GON-specific thinning parameters, RNFL in the inferior sector, and inferior to temporal macular GCIPL ratio showed overlap with posttreatment CON in the early MD losses with AUCs of 0.916 (95% CI 0.860-0.971; P < 0.001) and 0.890 (95% CI 0.811-0.968; P < 0.001), respectively. In comparison, CON-specific thinning parameters, superonasal, and inferonasal GCIPL showed overlap with CON at diagnosis for early MD losses. Overall, the nasal-to-temporal macular GCIPL ratio showed good discrimination between CON and GON throughout the MD range, with an AUC of 0.923 (95% CI 0.870-0.976; P < 0.001). Comparing GON with all stages of CON, the cut-point of 0.95 showed the lower nasal-to-temporal GCIPL ratio had a sensitivity of 72% and specificity of 90% for CON. However, the cut-point of 1.10 showed the superior-to-inferior GCIPL ratio had a sensitivity of 60% and specificity of 98% for GON.

Variable structure and function relationship of compressive optic neuropathy at the time of diagnosis.

PURPOSE: To illustrate the structure-function relationship of compressive optic neuropathy (CON) at the time of diagnosis. PATIENTS AND METHODS: Thirty-two eyes of newly diagnosed suprasellar CON and 60 healthy eyes were included in the study. The peripapillary retinal nerve fiber layer (RNFL) thickness and macular ganglion cell-inner plexiform layer (GCIPL) thickness were obtained using Cirrus spectral domain optical coherence tomography (SD-OCT). CON eyes were stratified based on the similar degree and pattern of both RNFL and GCIPL. RESULTS: From 32 eyes of newly diagnosed suprasellar CON eyes, 27 eyes had a predominantly nasal hemiretina thinning of macular GCIPL, 4 eyes showed a generalized macular thinning, and 1 eye showed a predominantly superior macular thinning. The corresponding temporal peripapillary RNFL thinning with nasal hemiretina GCIPL thinning were inconsistently manifested. Structure-function analysis of stratified CON eyes with similar thinning profiles showed that a range rather than a fixed value of visual field loss based on mean deviation (MD) index was associated to each thinning profile. The maximal limit of visual field loss range was ubiquitously nonrestricted to any structural thinning profile. While the minimal limit of the associated MD range was gradually reduced from 0 to about -16.0 dB, the nasal hemiretina macular GCIPL thinning was the only manifestation and decreased from 75 to 45 µm. However, the different degrees of temporal hemiretina macular GCIPL and superior-inferior peripapillary RNFL thinning were only seen in 10 of 32 eyes of which their nasal hemiretina GCIPL and temporal RNFL thinning had reached significant thinning. Interestingly when present, the minimal limit of associated MD range continued to decrease from -16.0 to -32.0 dB. CONCLUSION: CON eyes can present with variable structure and function relationship at the time of diagnosis. Using structural parameters at the time of diagnosis to predict the prognosis should be used with caution.

Optical coherence tomography in central nervous system demyelinating diseases related optic neuritis.

AIM: To compare the thickness of the peripapillary retinal nerve fiber layer (RNFL) and ganglion cell-inner plexiform layer (GCIPL) among patients with various forms of optic neuritis (ON) and to identify whether any particular parameters or their thinning pattern can be used to distinguish the type of ON. METHODS: This prospective study was conducted at the Department of Ophthalmology, Faculty of Medicine, Siriraj Hospital, Thailand, between January, 2015 and December, 2016. We enlisted patients over 18 years of age with history of ON and categorized patients into 4 groups: 1) aquaporin 4 antibodies (AQP4-IgG) positive; 2) multiple sclerosis (MS); 3) myelin oligodendrocyte glycoprotein antibodies (MOG-IgG) positive; 4) idiopathic-ON patients. Healthy controls were also included during the same study period. All patients underwent complete ophthalmological examination and spectral domain optical coherence tomography (OCT) imaging to analyze RNFL and GCIPL thickness after at least 3mo since the last episode of acute ON. The generalized estimating equation (GEE) models were used to compare the data amongst ON groups. RESULTS: Among 87 previous ON eyes from 57 patients (43 AQP4-IgG+ON, 17 MS-ON, 8 MOG-IgG+ON, and 19 idiopathic-ON), mean logMAR visual acuity of AQP4-IgG+ON, MS-ON, MOG-IgG+ON, and idiopathic-ON groups was 0.76±0.88, 0.12±0.25, 0.39±0.31, and 0.75±1.08, respectively. Average, superior, and inferior RNFL were significantly reduced in AQP4-IgG+ON, MOG-IgG+ON and idiopathic-ON eyes, relative to those of MS-ON. Differences were not statistically significant for RNFL or GCIPL between the AQP4-IgG+ON and MOG-IgG+ON groups, whereas visual acuity in MOG-IgG+ON was slightly, but not significantly, better (0.39 vs 0.76). Although RNFL thickness in MOG-IgG+ON was significantly reduced as compared to MS-ON, mean visual acuity and GCIPL were not different. CONCLUSION: Thinning of superior and inferior quadrants of RNFL are more commonly seen in MOG-IgG+ON and AQP4-IgG+ON. Long term visual acuity in MOG-IgG+ON is often better than AQP4-IgG+ON, whereas the structural change from OCT is comparable.

Visual function and inner retinal structure correlations in aquaporin-4 antibody-positive optic neuritis.

PURPOSE: To investigate the correlation between visual function and thinning of the retinal nerve fiber layer (RNFL) and the macular ganglion cell-inner plexiform layer (GCIPL) as measured by optical coherence tomography (OCT) in eyes with aquaporin-4 IgG-positive optic neuritis (AQP4-IgG-positive ON). STUDY DESIGN: Prospective study. METHODS: Patients with a history of ON were categorized into 2 groups: the AQP4-IgG-positive group and the AQP4-IgG-negative group. Patients with multiple sclerosis were excluded. All patients underwent ophthalmologic examination and OCT imaging at least 6 months after the last episode of acute ON. Visual function and inner retinal structure correlations were analyzed using Pearson correlation and regression analyses. RESULTS: Thirty-one previous ON eyes of 17 AQP4-IgG-positive patients and 21 previous ON eyes of 15 AQP4-IgG-negative patients were registered. Visual function, especially the visual field, was better correlated with RNFL than with macular GCIPL. The best correlation between visual function and RNFL was the linear model, whereas the best correlation between visual function and GCIPL was the nonlinear model (inverse regression). Regression models revealed worse visual function in AQP4-IgG-positive ON than in AQP4-IgG-negative ON, whereas no differences in RNFL and GCIPL were found between the 2 groups. CONCLUSIONS: RNFL measured by OCT can be a useful retinal structure for estimating and monitoring visual field loss in AQP4-IgG-positive ON patients, particularly in patients whose visual field cannot be quantitated. The correlation between visual function and the inner retinal structure of eyes with AQP4-IgG is unique and differs from that of eyes without AQP4-IgG.

Effective enhancement of Pseudomonas stutzeri D-phenylglycine aminotransferase functional expression in Pichia pastoris by co-expressing Escherichia coli GroEL-GroES.

BACKGROUND: D-phenylglycine aminotransferase (D-PhgAT) of Pseudomonas stutzeri ST-201 catalyzes the reversible stereo-inverting transamination potentially useful in the application for synthesis of D-phenylglycine and D-4-hydroxyphenylglycine using L-glutamate as a low cost amino donor substrate in one single step. The enzyme is a relatively hydrophobic homodimeric intracellular protein difficult to express in the soluble functionally active form. Over-expression of the dpgA gene in E. coli resulted in the majority of the D-PhgAT aggregated into insoluble inclusion bodies that failed to be re-natured. Expression in Pichia pastoris was explored as an alternative route for high level production of the D-PhgAT. RESULTS: Intracellular expression of the codon-optimized synthetic dpgA gene under the PAOX1 promoter in P. pastoris resulted in inactive D-PhgAT associated with insoluble cellular fraction and very low level of D-PhgAT activity in the soluble fraction. Manipulation of culture conditions such as addition of sorbitol to induce intracellular accumulation of osmolytes, addition of benzyl alcohol to induce chaperone expression, or lowering incubation temperature to slow down protein expression and folding rates all failed to increase the active D-PhgAT yield. Co-expression of E. coli chaperonins GroEL-GroES with the D-PhgAT dramatically improved the soluble active enzyme production. Increasing gene dosage of both the dpgA and those of the chaperones further increased functional D-PhgAT yield up to 14400-fold higher than when the dpgA was expressed alone. Optimization of cultivation condition further increased D-PhgAT activity yield from the best co-expressing strain by 1.2-fold. CONCLUSIONS: This is the first report on the use of bacterial chaperones co-expressions to enhance functional intracellular expression of bacterial enzyme in P. pastoris. Only two bacterial chaperone genes groEL and groES were sufficient for dramatic enhancement of functionally active D-PhgAT expression in this yeast. With the optimized gene dosage and chaperone combinations, P. pastoris can be attractive for intracellular expression of bacterial proteins since it can grow to a very high cell density which is translated into the higher volumetric product yield than the E. coli or other bacterial systems.

Independent saturation of three TrpRS subsites generates a partially assembled state similar to those observed in molecular simulations.

Two new crystal structures of Bacillus stearothermophilus tryptophanyl-tRNA synthetase (TrpRS) afford evidence that a closed interdomain hinge angle requires a covalent bond between AMP and an occupant of either pyrophosphate or tryptophan subsite. They also are within experimental error of a cluster of structures observed in a nonequilibrium molecular dynamics simulation showing partial active-site assembly. Further, the highest energy structure in a minimum action pathway computed by using elastic network models for Open and Pretransition state (PreTS) conformations for the fully liganded TrpRS monomer is intermediate between that simulated structure and a partially disassembled structure from a nonequilibrium molecular dynamics trajectory for the unliganded PreTS. These mutual consistencies provide unexpected validation of inferences drawn from molecular simulations.

Crystallization and preliminary X-ray crystallographic analysis of d-phenylglycine aminotransferase from Pseudomonas stutzeri ST201.

d-Phenylglycine aminotransferase (d-PhgAT) catalyzes the reversible transamination of d-phenylglycine to l-glutamate with 2-oxoglutarate as the amino-group acceptor. Crystals of substrate-free Pseudomonas stutzeri d-PhgAT bound to the cofactor pyridoxal-5'-phosphate (PLP) were obtained by the hanging-drop vapour-diffusion method using ammonium sulfate as a precipitant. The crystals belong to space group P3(1)21 or P3(2)21, with unit-cell parameters a = b = 75.155, c = 147.554 A. The asymmetric unit contains one molecule of d-PhgAT and has a solvent content of 50.0%. A complete native X-ray diffraction data set was collected from a single crystal at 100 K to a resolution of 2.3 A.