Bilateral Pseudomonas aeruginosa endophthalmitis following bilateral simultaneous cataract surgery.

A bilateral simultaneous cataract surgery (BSCS) was performed on a 67-year-old man. The surgeon had not changed the surgical settings in between the two procedures for the two eyes. The patient developed fulminant bilateral endophthalmitis a day following the BSCS. Intravitreal culture grew Pseudomonas aeruginosa . The source of infection was not found. Immediate bilateral vitrectomy and intravitreal, subconjunctival, topical and systemic antibiotic did not save the eyes. Patient ended up with bilateral visual loss.

Validation of Farsi Translation of the Ocular Surface Disease Index.

PURPOSE: To develop and validate a Farsi version of Ocular Surface Disease Index (OSDI) for the Iranian population. METHODS: This study was a translation and cross-cultural adaptation and validation of Farsi version of OSDI. Four bilingual (English-Persian) individual including three physicians and one native English teacher were asked to translate the original English OSDI questionnaire in Farsi. Following back and forth translation, integration and pilot check, the translation team came to consensus on translation. Consecutive patients visited in ophthalmology clinic, underwent comprehensive general ophthalmology exam and specific assessments for dry eye including non-anesthetic Schirmer's test, fluorescein tear break-up time, Fluorescein and Rose Bengal staining and Farsi OSDI (F-OSDI). F-OSDI was again rechecked within 2-7 days after the examination. RESULTS: Forty-four participants were enrolled into study. Thirty-two (72.7%) were male and 12 (27.3%) female. Mean age of participants was 45.5 (SD = ±15.97, range = 18-80) years. Twenty five percent were less than 31 years old and 10% percent older than 65. The cronbach's alpha for the questionnaire was 0.807. Questions number 7, 8 showed excellent, and question12 showed good internal consistency, respectively. There was a significant correlation between all pre measures and post assessments. CONCLUSION: The obtained F-OSDI showed acceptable internal consistency and test-retest reliability. This F-OSDI could be used for assessment of dry eye, ocular surface discomfort and quality of life in Iranian and Farsi speaking populations.

Molecular dynamic study of human prion protein upon D178N mutation: new perspective to H-bonds, salt bridges and the critical amino acids.

The molecular dynamics simulation method was used to investigate the structural details for human prion protein (PrPN) and its D178N mutant (PrPM). Root-mean-square fluctuations (RMSFs) and the root-mean-square deviations (RMSDs) showed an increase in the flexibility and high dynamic plasticity of PrPM. Average Total energy for PrPM and PrPN sequentially was -2.975 x105 (kJmol-1) and -3.193 x 105 (kJmol-1). The results showed conformational rearrangement susceptibility for PrPM. For PrPM, highly surface-exposed Glu196 and Arg136 caused hydrogen bond weakening and electrostatic interactions changes in salt bridges. Hydrogen bond weakening under mutation can be mentioned as the leader of conformational changes and disease-related conversions. Contrary to some reports, the contributions of electrostatic interactions of Glu146-Arg208 and Arg156-Glu196 salt bridges for PrPN is less than of these interactions for PrPM. These interactions can pave the way to conformational changes in PrPM. The results showed that the role of the hydrogen bonds in the stability of human prion protein is more important than these salt bridges. The calculation of the solvent accessible surface area showed that the conformational plasticity in PrPM is mainly due to Asn residues that were solvent exposed. Conformational changes in the specific amino acids can affect metal-ion occupancy and function. The secondary structure has also showed that the structural transition arose from D178N mutation and occurs in specific residues. Our studies support the large scale effects of electrostatic forces at key position 178 of prion. As a result, the conformational rearrangements happen by eliminating only a single negative charge because of the mutation induced global forces in the prion structure. These rearrangements can be considered as a molecular switch, which triggers the initial stages of the conformational transition.