Pupillary Light Reflex and Multimodal Imaging in Patients With Central Serous Chorioretinopathy.

Purpose: The purpose of this study was to investigate and compare the corresponding alterations of the pupillary response between acute and chronic central serous chorioretinopathy (CSC) and between different disease categories. Methods: We recruited patients with unilateral acute and chronic CSC. An eye tracker was applied to determine the pupillary light reflex (PLR) and evaluate the following PLR metrics in healthy eyes: pupil diameter, diameter changes, including relative constriction amplitude (AMP%), and re-dilation ratio (D1%). Baseline optical coherence tomography (OCT), and fluorescein and indocyanine green angiography (FA/ICGA) were performed to analyze the relationship between pupillary response and retinal/choroidal architecture. Results: In total, 52 patients were enrolled, including 25 with acute CSC and 27 with chronic CSC. Compared to the chronic CSC group, the acute CSC group displayed a significantly larger baseline pupil diameter (BPD; of 5.51 mm, P = 0.015), lower AMP% (34.40%, P = 0.004), and higher D1% (93.01%, P = 0.002), indicating sympathetic overactivity. On OCT, the total macular volume was positively correlated with the D1% (r = 0.48, P = 0.005) and negatively with AMP (r = -0.47, P = 0.007). On ICGA, the intense choroidal vascular hyperpermeability (CVH) group displayed a greater BPD than the nonintense CVH group. Additionally, 9 cases with later recurrent episodes following therapy showed a lower AMP% and higher D1% than the nonrecurrent group. Conclusions: The PLR revealed sympathetic excitation in patients with acute CSC. The stronger D1% was significantly associated with greater total macular volume, and it may be a potential biomarker for predicting the later recurrence of CSC.

Macular hole and vitreous hemorrhage subsequent to stereotactic hypofractionated radiotherapy for choroidal melanoma: A case report and review of the literature.

Choroidal melanoma is the leading primary intraocular tumor with potentially fatal outcomes in adults. The coexistence of choroidal melanoma and a macular hole is extremely rare, and treatment strategies and information on the prognosis of associated complications are currently lacking. We report the first case of choroidal melanoma complicated with a macular hole and vitreous hemorrhage after stereotactic hypofractionated radiotherapy in Japan, and review the relevant literature in relation to the possible mechanisms, treatment strategies, and outcomes. An 83-year-old male with choroidal melanoma was treated with stereotactic hypofractionated radiotherapy in January 2021. Five months later, a full-thickness macular hole developed, followed by an acute massive vitreous hemorrhage about 2 weeks later. Following confirmation of tumor regression, the patient underwent a pars plana vitrectomy and internal limiting membrane peeling. The macular hole was closed postoperatively and the patient's best-corrected visual acuity improved to 20/125. There was no evidence of intraocular tumor dissemination or distant metastases during follow-up. A systematic literature search only identified 10 previous cases of choroidal melanoma with a macular hole in eight reports worldwide, mainly in females. Macular edema may be the primary cause of macular hole formation in these cases. Most patients who underwent vitrectomy for complications after tumor regression achieved a good prognosis. The development of a macular hole is a rare complication associated with choroidal melanoma. Anterior-posterior traction of posterior vitreous detachment and secondary macular edema may have contributed to the formation of the macular hole in the current case.

Pupillary Responses Reveal Autonomic Regulation Impairments in Patients With Central Serous Chorioretinopathy.

Purpose: This study assessed the autonomic nervous system in patients with central serous chorioretinopathy (CSC) by simultaneously measuring pupillary responses and heart rate variability (HRV). Methods: We recruited 33 patients with CSC and 26 age- and sex-matched healthy controls. Using a pupillometry and acceleration plethysmography system, we measured the participants' pupillary light reflex and HRV simultaneously, and compared the following parameters between the two groups: the pupil diameters, diameter changes, and time and frequency domain HRV indices (high frequency power: HF; low frequency power: LF; log LF/HF ratio). Additional data from the Profile of Mood States (POMS) and pupillary responses during mental tasks were also analyzed. Results: The CSC group had a significantly lower constriction amplitude and a higher re-dilation ratio compared with the control group, indicating parasympathetic inhibition and sympathetic activation. For the HRV measures, the CSC group demonstrated significantly lower HF and higher LF and log LF/HF ratio, indicative of higher sympathetic activity. The CSC group also showed significantly larger pupil dilation during tasks of moderate difficulty, and higher negative/lower positive POMS mood scores. Further analyses also revealed that the baseline pupil diameter was significantly larger in patients with active as opposed to chronic CSC. Conclusions: Pupillary responses and HRV measures both revealed sympathetic activation and parasympathetic attenuation in patients with CSC. Larger pupil dilation during mental tasks in CSC could be a potential marker of psychophysiological stress.

A multicentre study of the risk factors associated with recurrence of central serous chorioretinopathy.

PURPOSE: To investigate potential clinical and multimodal imaging factors in central serous chorioretinopathy (CSC) recurrence. METHODS: The study was performed at nine Japanese medical institutions for patients who had experienced an active CSC episode. Demographic data and medical history were reviewed retrospectively. Significant differences in chronic manifestation, leakage site, leakage point number, leakage intensity, choroidal hyperpermeability, central retinal thickness (CRT) and subfoveal choroidal thickness were analysed between the recurrence and non-recurrence groups. RESULTS: In total, 538 eyes (538 patients) diagnosed with CSC (402 men, 136 women; mean age: 53.4 ± 11.9 years) were enrolled. Among them, 253 eyes (47.0%) developed ≥1 recurrence (follow-up: 15.9 ± 13.5 months, range 3-86 months). Univariate and multivariate analyses indicated that a history of corticosteroid use (odds ratio [OR], 5.52; 95% confidence interval [CI], 1.39-21.92; p = 0.015), bilateral disease (OR, 3.94; 95% CI, 1.47-10.6; p = 0.007), chronic manifestations (OR, 7.12; 95% CI, 2.93-17.28; p < 0.001), non-intense fluorescein leakage (OR, 3.34; 95% CI, 1.44-7.75; p = 0.005) and initial CRT (OR, 0.997; 95% CI, 0.993-0.999; p = 0.049) were significantly associated with CSC recurrence. Receiver operating characteristic curves were created, and the area under the curve for the multivariate logistic regression model of these five factors was 0.814. CONCLUSION: Patients with CSC who received corticosteroids and had bilateral disease, chronic manifestation, non-intense fluorescein leakage on fluorescein angiography or a relatively thinner CRT should be closely monitored to identify whether they are at high risk of recurrence.

Risk factors and characteristics of central serous chorioretinopathy with later development of macular neovascularisation detected on OCT angiography: a retrospective multicentre observational study.

OBJECTIVE: To identify the risk factors and characteristics of central serous chorioretinopathy (CSC) with subsequent macular neovascularisation (MNV) detected on optical coherence tomography angiography (OCTA). METHODS AND ANALYSIS: We included patients from six institutions who were initially diagnosed with CSC and subsequently did or did not develop MNV detected by OCTA. Potential influencing factors were identified by evaluating the patients' baseline demographics, multimodal fundus imaging, treatment options, recurrence and outcomes in both groups. RESULTS: We enrolled 176 eyes in 152 patients (112 men, 40 women; mean age: 52.1±10.4 years) with a mean follow-up of 30.4±16.3 months. Secondary MNV was present in 23 eyes (13.1%), and non-MNV was observed in 153 eyes (86.9%) by OCTA. Multivariate analysis revealed that older age (OR 1.06; 95% CI 1.01 to 1.11; p=0.014), chronic CSC (OR 3.05; 95% CI 1.12 to 8.30; p=0.029), leakage sites within the fovea on fluorescein angiography (OR 7.60; 95% CI, 1.89 to 30.48; p=0.004) and recurrent fluid within the first year (OR 5.12; 95% CI 1.66 to 15.77; p=0.012) were risk factors for subsequent MNV. Moreover, eyes with CSC complicated with MNV were characterised by poor visual acuity and low complete fluid resolution rates. CONCLUSION: The factors associated with MNV secondary to CSC were older age, higher rates of chronic CSC and recurrence, and foveal leakage points on fluorescein angiography.

Comparative analysis of miRNAs of two rapeseed genotypes in response to acetohydroxyacid synthase-inhibiting herbicides by high-throughput sequencing.

Acetohydroxyacid synthase (AHAS), also called acetolactate synthase, is a key enzyme involved in the first step of the biosynthesis of the branched-chain amino acids valine, isoleucine and leucine. Acetohydroxyacid synthase-inhibiting herbicides (AHAS herbicides) are five chemical families of herbicides that inhibit AHAS enzymes, including imidazolinones (IMI), sulfonylureas (SU), pyrimidinylthiobenzoates, triazolinones and triazolopyrimidines. Five AHAS genes have been identified in rapeseed, but little information is available regarding the role of miRNAs in response to AHAS herbicides. In this study, an AHAS herbicides tolerant genotype and a sensitive genotype were used for miRNA comparative analysis. A total of 20 small RNA libraries were obtained of these two genotypes at three time points (0h, 24 h and 48 h) after spraying SU and IMI herbicides with two replicates. We identified 940 conserved miRNAs and 1515 novel candidate miRNAs in Brassica napus using high-throughput sequencing methods combined with computing analysis. A total of 3284 genes were predicted to be targets of these miRNAs, and their functions were shown using GO, KOG and KEGG annotations. The differentiation expression results of miRNAs showed almost twice as many differentiated miRNAs were found in tolerant genotype M342 (309 miRNAs) after SU herbicide application than in sensitive genotype N131 (164 miRNAs). In additiond 177 and 296 miRNAs defined as differentiated in sensitive genotype and tolerant genotype in response to SU herbicides. The miR398 family was observed to be associated with AHAS herbicide tolerance because their expression increased in the tolerant genotype but decreased in the sensitive genotype. Moreover, 50 novel miRNAs from 39 precursors were predicted. There were 8 conserved miRNAs, 4 novel miRNAs and 3 target genes were validated by quantitative real-time PCR experiment. This study not only provides novel insights into the miRNA content of AHAS herbicides tolerant rapeseed in response to AHAS herbicides, but also demonstrates that miRNAs may be involved in AHAS herbicides tolerance.

Polymorphism of flucloxacillin sodium.

The polymorphism of flucloxacillin sodium has not been discussed sufficiently so far. Flucloxacillin sodium which was crystallized with different solvents, was found to exist in amorphism and three crystal forms (I, II, III). This results were confirmed by infra-red (IR) spectra, thermogravimetry (TG), X-ray diffraction analysis (XRD) and equilibrium solubility. It is noticed that form III has very good solubility in phosphate buffer solution, with an average solubility of 0.86 g (20-40 degrees C). However, more efforts are needed to carry out and decide whether this form can be used for industrial production.

Mutation of a conserved tryptophan in the chitin-binding cleft of Serratia marcescens chitinase A enhances transglycosylation.

Family 18 chitinases have the signature peptide DGXDXDXE forming the fourth beta-strand in the (beta/alpha)8-barrel of their catalytic domain. The carboxyl-end glutamic acid, E315 in Serratia marcescens chitinase A, serves as the acid/base during chitin hydrolysis, and the side-chain of the preceding aspartic acid, D313, helps to position correctly the N-acetyl moiety of the glycosyl sugar undergoing hydrolysis. Chitin substrates are bound within a long cleft across the top of the barrel, whose floor consists of aromatic residues that hydrophobically stack with every other GlcNAc. Alanine substitution of the conserved Trp167 at the -3 subsite in Serratia marcescens chitinase A enhanced transglycosylation. Higher oligosaccharides were formed from both chitin tetra- and pentasaccharide, and the only hydrolytic product from chitin trisaccharide was the disaccharide. Greater retention of the glycosyl fragment at the active site of the -3 mutant of Serratia marcescens chitinase A might favor transglycosylation due to a stabilized conformation of its D313.

The hyperthermophile protein Sso10a is a dimer of winged helix DNA-binding domains linked by an antiparallel coiled coil rod.

Sso10a is a member of a group of DNA-binding proteins thought to be important in chromatin structure and regulation in the hyperthermophilic archaeon Sulfolobus solfataricus. We have determined the structure of Sso10a to 1.47A resolution directly with unlabelled native crystals by a novel approach using sulfur single-wavelength anomalous scattering (SAS) from a chromium X-ray source. The 95 amino acid residue protein contains a winged helix DNA-binding domain with an extended C-terminal alpha-helix that leads to dimerization by forming a two-stranded, antiparallel coiled-coil rod. The winged helix domains are at opposite ends of the extended coiled coil with two putative DNA-recognition helices separated by 55A and rotated by 83 degrees. Formation of stable dimers in solution is demonstrated by both analytical ultracentrifugation and differential scanning calorimetry. With a T0 of 109 degrees C, Sso10a is one of the most stable two-stranded coiled coils known. The coiled coil contains a rare aspartate residue (D69) in the normally hydrophobic d position of the heptad repeat, with two aspartate-lysine (d-g') interhelical ion pairs in the symmetrical dimer. Mutation of D69 to alanine resulted in an increase in thermal stability, indicating that destabilization resulting from the partially buried aspartate residue cannot be offset by ion pair formation. Possible DNA-binding interactions are discussed on the basis of comparisons to other winged helix proteins. The structure of Sso10a provides insight into the structures of the conserved domain represented by COG3432, a group of more than 20 hypothetical transcriptional regulators coded in the genomic sequences of both crenarchaeota and euryarchaeota.

High resolution crystal structure of human Rab9 GTPase: a novel antiviral drug target.

Rab GTPases and their effectors facilitate vesicular transport by tethering donor vesicles to their respective target membranes. Rab9 mediates late endosome to trans-Golgi transport and has recently been found to be a key cellular component for human immunodeficiency virus-1, Ebola, Marburg, and measles virus replication, suggesting that it may be a novel target in the development of broad spectrum antiviral drugs. As part of our structure-based drug design program, we have determined the crystal structure of a C-terminally truncated human Rab9 (residues 1-177) to 1.25-A resolution. The overall structure shows a characteristic nucleotide binding fold consisting of a six-stranded beta-sheet surrounded by five alpha-helices with a tightly bound GDP molecule in the active site. Structure-based sequence alignment of Rab9 with other Rab proteins reveals that its active site consists of residues highly conserved in the Rab GTPase family, implying a common catalytic mechanism. However, Rab9 contains seven regions that are significantly different in conformation from other Rab proteins. Some of those regions coincide with putative effector-binding sites and switch I and switch II regions identified by structure/sequence alignments. The Rab9 structure at near atomic resolution provides an excellent model for structure-based antiviral drug design.

Crystal structure of type IIE restriction endonuclease EcoRII reveals an autoinhibition mechanism by a novel effector-binding fold.

EcoRII is a type IIE restriction endonuclease that interacts with two copies of the DNA recognition sequence 5'CCWGG, one being the actual target of cleavage, the other serving as the allosteric effector. The mode of enzyme activation by effector binding is unknown. To investigate the molecular basis of activation and cleavage mechanisms by EcoRII, the crystal structure of EcoRII mutant R88A has been solved at 2.1A resolution. The EcoRII monomer has two domains linked through a hinge loop. The N-terminal effector-binding domain has a novel DNA recognition fold with a prominent cleft. The C-terminal catalytic domain has a restriction endonuclease-like fold. Structure-based sequence alignment identified the putative catalytic site of EcoRII that is spatially blocked by the N-terminal domain. The structure together with the earlier characterized EcoRII enzyme activity enhancement in the absence of its N-terminal domain reveal an autoinhibition/activation mechanism of enzyme activity mediated by a novel effector-binding fold. This is the first case of autoinhibition, a mechanism described for many transcription factors and signal transducing proteins, of a restriction endonuclease.

Structure of an insect delta-class glutathione S-transferase from a DDT-resistant strain of the malaria vector Anopheles gambiae.

Glutathione S-transferases (GSTs) are a major family of detoxification enzymes which possess a wide range of substrate specificities. Most organisms possess many GSTs belonging to multiple classes. Interest in GSTs in insects is focused on their role in insecticide resistance; many resistant insects have elevated levels of GST activity. In the malaria vector Anopheles gambiae, elevated GST levels are associated with resistance to the organochlorine insecticide DDT [1,1,1-trichloro-2,2-bis-(p-chlorophenyl)ethane]. This mosquito is the source of an insect GST, agGSTd1-6, which metabolizes DDT and is inhibited by a number of pyrethroid insecticides. The crystal structure of agGSTd1-6 in complex with its inhibitor S-hexyl glutathione has been determined and refined at 2.0 A resolution. The structure adopts a classical GST fold and is similar to those of other insect delta-class GSTs, implying a common conjugation mechanism. A structure-based model for the binding of DDT to agGSTd1-6 reveals two subpockets in the hydrophobic binding site (H-site), each accommodating one planar p-chlorophenyl ring.

A single mutation of restriction endonuclease EcoRII led to a new crystal form that diffracts to 2.1 A resolution.

R88A, a mutant of the type IIE restriction endonuclease EcoRII, has been crystallized in space group P2(1), with unit-cell parameters a = 58.7, b = 92.4, c = 88.3 A, beta = 108.1 degrees. There are two monomers in the asymmetric unit and the solvent content is estimated to be 50% by volume. The crystals diffract to 2.1 A resolution, which is much higher than that of the wild type, which diffracted to 2.8 A resolution. The mutant crystals have been used in the identification of an excellent heavy-atom derivative.