A rare case of Panophthalmitis due to cobra bite.

PURPOSE: Ocular manifestations of snake bite are rare, ranging from direct injury to the eye from snake venom or indirect injury due to antivenom. We report a rare case of cobra bite causing panophthalmitis due to indirect injury as a result of snake venom toxin related tissue necrosis and susceptibility to secondary infections. METHODS: Observational case report. External photographs, slit lamp photos, ultrasonography of the eye and histopathology of the eviscerated eye were used to characterize and describe the clinical findings. Thirty-nine-years-old male farmer presented with history of cobra snake bite on his right index finger and developed right eye sudden onset pain and redness 3 days later. On examination, features were suggestive of panophthalmitis and the eye had to be eviscerated with scleral excision. CONCLUSION: It is important for ophthalmologist to be aware of such grave consequences of snake bite to be prepared for the emergency management of such cases.

Development and characterization of DNA aptamer against Retinoblastoma by Cell-SELEX.

Retinoblastoma (RB) is the most common paediatric intraocular tumour. The management of RB has improved the survival and vision with recent advances in the treatment. Improved therapeutic approaches focussing on targeting tumours and minimizing the treatment-associated side effects are being developed. In this study, we generated a ssDNA aptamer against RB by cell-SELEX and high-throughput sequencing using Weri-RB1 cell line as the target, and Muller glial cell line Mio-M1 as the control. Three aptamers were selected based on the number of repetitions in NGS and phylogenetic relationship and evaluated by flow cytometry to assess their binding affinity and selectivity. The dissociation constant, Kd values of three selected aptamers were found to be in the nanomolar range. Aptamer VRF-CSRB-01 with the best binding affinity and a Kd value of 49.41 ± 7.87 nM was further characterized. The proteinase and temperature treatment indicated that VRF-CSRB-01 targets surface proteins, and has a good binding affinity and excellent selectivity under physiological conditions. The aptamer VRF-CSRB-01 was stable over 72 h in serum and 96 h in cerebral spinal fluid and vitreous. With the high affinity, specificity, stability and specific recognition of clinical RB tumours, VRF-CSRB-01 aptamer holds potential for application in diagnosis and targeting RB.

Masson's tumor of the ocular surface - A rare clinical entity.

Masson's tumor or intravascular papillary endothelial hyperplasia (IPEH) is a benign vascular lesion usually involving the head-and-neck region. On histopathological examination, it consists of reactive proliferation of endothelial cells with papillary formations which is the key to diagnosis. This rare entity was first described in 1923 by Pierre Masson. Lesions involving orbit and eyelids have been reported before. Here, we report a case of Masson's tumor which occurred in the lid margin and later in the conjunctiva which regressed completely after excision.

Plasma cell granuloma of the conjunctiva in a young female.

Plasma cell granuloma is a rare non-neoplastic inflammatory condition of unknown etiology commonly involving lung and gastrointestinal tract. Conjunctival disease per se is very rare and usually associated with involvement of other organs. We report a case of conjunctival plasma cell granuloma without any systemic involvement in a 9-year-old girl who presented with bilateral reddish vascularised subconjunctival episcleral mass. An excision biopsy of the mass in the left eye followed by histopathologic examination and Immunohistochemistry confirmed the diagnosis. At 1 year follow-up, the child had no recurrence in the operated eye whereas the lesion remained the same in the other eye despite systemic treatment with immunosuppressants. This case is being reported for its rarity and to insist on the mandatory need for a thorough systemic workup to identify multiorgan involvement as well as to rule out other systemic disorders.

Autosomal dominant retinitis pigmentosa with toxic gain of function: Mechanisms and therapeutics.

Autosomal dominant retinitis pigmentosa is a form of retinitis pigmentosa, an inherited retinal degenerative disorder characterized by progressive loss of photoreceptors eventually leading to irreversible loss of vision. Mutations in genes involved in the basic functions of the visual system give rise to this condition. These mutations can either lead to loss of function or toxic gain of function phenotypes. While autosomal dominant retinitis pigmentosa caused by loss of function can be ideally treated by gene supplementation with a single vector to address a different spectrum of mutations in a gene, the same strategy cannot be applied to toxic gain of function phenotypes. In toxic gain of function phenotypes, the mutation in the gene results in the acquisition of a new function that can interrupt the functioning of the wildtype protein by various mechanisms leading to cell toxicity, thus making a single approach impractical. This review focuses on the genes and mechanisms that cause toxic gain of function phenotypes associated with autosomal dominant retinitis pigmentosa and provide a bird's eye view on current therapeutic strategies and ongoing clinical trials.

Atypical Case of Bilateral Chandler Syndrome With Recurrent Band Keratopathy.

PURPOSE: To report a unique case of bilateral Chandler syndrome with recurrent band keratopathy. METHODS: This is a retrospective observational case report. RESULTS: A 39-year-old Asian man presented with progressive painless diminution of vision in both eyes for 6 years. Examination revealed diffuse corneal edema, hammered silver appearance of endothelium with guttae-like lesions, and corectopia in the right eye and mild corneal edema, central band keratopathy, and guttae-like lesions on the endothelium and peripheral anterior synechiae in the left eye. Routine specular microscopy, confocal microscopy, and pachymetry were performed. A clinical diagnosis of bilateral Chandler syndrome with band keratopathy was made. Superficial epithelial keratectomy with ethylenediaminetetraacetic acid (EDTA) chelation was performed in the left eye first, followed by Descemet-stripping automated endothelial keratoplasty in the right eye. Histopathological examination of the surgically excised Descemet membrane in the right eye showed multilayered endothelium with adhered epithelial cells consistent with Chandler syndrome. At 9-month follow-up, the right eye showed a clear cornea with an attached graft and the left eye revealed recurrence of central band keratopathy for which repeat EDTA chelation was successfully performed. CONCLUSIONS: Recurrent band keratopathy coincident with endothelial dysfunction in iridocorneal endothelial syndrome can be repeatedly treated with EDTA chelation, whereas endothelial keratoplasty might be delayed until the time point of corneal decompensation.

MYD88 L265P mutation in intraocular lymphoma: A potential diagnostic marker.

PURPOSE: Vitreoretinal lymphoma (VRL) is the most common intraocular lymphoma (IOL). This can be either primary or secondary to the central nervous system lymphoma. The diagnosis of primary intraocular lymphoma (PIOL) currently relies on clinical diagnosis and cytological analysis of the vitreous or subretinal biopsy. Although most cases are diagnosed without much issue, the limited amount of vitreous fluid, subjectivity in cytological reporting, and special expertise in ocular pathology make the diagnosis challenging. MYD88 L265P mutation has been implicated to have diagnostic utility in PIOL. In this study, we screened consecutive vitreous biopsies for the presence of MYD88 L265P mutation to understand its diagnostic utility compared to conventional cytological analysis. METHODS: Cytological analysis and MYD88 L265P mutation by PCR-based sequencing and restriction fragment length polymorphism (RFLP) were carried out on consecutive vitreous and subretinal biopsies collected from 21 patients. The diagnostic utility of the cytology and MYD88 L265P mutation analysis were compared. RESULTS: Out of the 21 patients, 15 had clinical suspicion of having PIOL. Out of these suspected cases of PIOL, nine were confirmed on follow-up, while six were diagnosed as other intraocular pathologies. Diagnostic utility of MYD88 L265P mutation analysis revealed a sensitivity of 88.9%, specificity of 91.6%, positive and negative predictive value of 88.9% and 91.7%, respectively. Diagnostic accuracy of 90.5% was achieved with the mutation analysis that shows the superiority of MYD88 in both ruling in and ruling out PIOL. The diagnostic utility of MYD88 L265P mutation was superior to conventional cytological analysis. CONCLUSION: The analysis of MYD88 L265P mutation is reliable and efficient in the diagnosis of PIOL.

Clinical spectrum and management outcomes of Langerhans cell histiocytosis of the orbit.

Purpose: To describe the clinical spectrum and management outcomes of Langerhans cell histiocytosis (LCH) involving the orbit. Methods: Retrospective review of patients with orbital LCH presenting at the Sankara Nethralaya, Chennai, India, over the past 15 years. Demographic details, presenting features, radiology, histopathology, immunohistochemistry, and management outcomes were analyzed. Results: Nine patients were reviewed. The mean age of presentation was 10.12 ± 14.31 years (range: 6 weeks to 35 years). Eyelid swelling was the most common presenting feature (4, 44.4%), followed by proptosis (3, 33.3%). The mean duration of the presentation was 2.21 ± 2.77 months. Radiological investigations revealed orbital roof osteolytic defects in six (66.6%) patients. Six patients underwent near-complete excision of the mass while three underwent incisional biopsy. Histopathology revealed histiocytes with nuclear grooving and numerous eosinophils characteristic of LCH. The cells were positive for CD1a and S 100 antigens. None of the patients had any systemic involvement. Three received systemic steroids and four received systemic chemotherapy. At a mean follow-up of 17.85 ± 23.46 months, all had complete remission without any signs of recurrence. One patient was lost to follow-up after near-complete excision while one adult patient with a mass in the intraconal space had no recurrence after near-complete excision. Conclusion: LCH is a rare disorder of the orbit that commonly occurs in children and should be considered a differential for osteolytic lesions involving the orbit. All patients should undergo a systemic evaluation to rule out multifocal disease. The treatment depends upon disease extent and risk factors.

Rosai-Dorfman disease with isolated lacrimal gland enlargement.

Rosai-Dorfman Disease also called as Sinus Histiocytosis with Massive Lymphadenopathy is a rare, benign, idiopathic histiocytic proliferative disorder that occurs predominantly in children and young adults. Orbital involvement can occur in 11% of cases. Isolated lacrimal gland involvement without any local or systemic recurrence is very rare. To the best of our knowledge, only seven cases have been reported in the literature till date. Histopathological and immunohistochemical confirmation is essential in establishing the diagnosis. A benign course is usual, but in some cases, blindness or even fatality may result. We report a case of 30-year-old female with isolated lacrimal gland involvement and 19 months' follow-up.

Membrane Proteome of Invasive Retinoblastoma: Differential Proteins and Biomarkers.

PURPOSE: Retinoblastoma (RB) is a pediatric ocular cancer which is caused due to the aberrations in the RB1 gene. The changes in the membrane proteomics would help in understanding the development of the retinoblastoma and could identify candidates for biomarkers and therapy. EXPERIMENTAL DESIGN: Quantitative proteomics is performed on the enriched membrane fractions from pooled normal retina (n = 5) and pooled retinoblastoma tissues (n = 5). The proteins are tryptic-digested and tagged with iTRAQ labels. Orbitrap mass spectrometry is used to analyze and quantify the deregulated membrane proteins involved in the RB tumor progression. Immunohistochemistry (IHC) is used to further validate few of the differentially expressed proteins. RESULTS: A total of 3122 proteins are identified of which, 663 proteins are found to be deregulated with ≥two fold change in the RB tumor compared to the retina. 282 proteins are upregulated and 381 are downregulated with ≥2 peptide identifications. Bioinformatic analysis revealed that, most of the proteins are involved in the transport, cellular communication, and growth. Overexpression of lamin B1 (LMNB1) and transferrin receptor (TFRC) are observed in RB tumors using IHC. CONCLUSION AND CLINICAL RELEVANCE: The present study, is the first comprehensive quantitative membrane proteomic atlas of the differentially regulated proteins in RB compared to the retina. LMNB1 and TFRC could be potential biomarkers for this childhood cancer.

A rare case of giant multicystic solitary fibrous tumor of the orbit.

Solitary fibrous tumor (SFT) is a rare spindle cell tumor of the orbit of mesenchymal origin. Though these tumors are mostly solid, partial or complete cystic changes can rarely occur. Only six such previous cases of cystic fibrous tumor of the orbit have been mentioned in the literature. We report a case of an elderly male who presented with a huge left sided medial orbital mass. Magnetic resonance imaging showed a predominant cystic orbital mass separated by septae and suggested a diagnosis of Hydatid cyst. The patient underwent complete excision of the mass and histopathology and immunohistochemistry were suggestive of cystic SFT. Cystic degeneration in SFT is extremely rare and can be a harbinger of malignancy, and pose risk of recurrence. Close follow up and monitoring is required for all such cases.

'Nano-in-nano' hybrid liposomes increase target specificity and gene silencing efficiency in breast cancer induced SCID mice.

Gene silencing has immense potential in the treatment of cancer. However, enhancement of its efficiency requires the development of specifically targeted and safe carrier systems. Cationic carriers are generally limited by their immunogenicity. Hence, in this study, we report hybrid liposomes encapsulating Poly (L-lysine)-siRNA complex to silence epithelial cell adhesion molecule (EpCAM), highly expressed in epithelial cancers. The hybrid liposomes LL1 (Egg PC:DSPE-PEG, 10:0) and hybrid immunoliposomes LL2 (Egg PC:DSPE-PEG, 8:2) linked with EpCAM antibody as the targeting ligand showed an encapsulation efficiency of 70% and 86%, respectively. LL2 liposomes with a zeta potential of -26mV exhibited good colloidal stability in phosphate buffered saline containing bovine serum albumin and fetal bovine serum at 37°C. Cell uptake studies showed increased uptake of the LL2 when compared to LL1 liposomes. Finally, the hybrid immunoliposomes were evaluated for their efficacy in regressing the tumor volume in SCID mice. Eight doses each of 0.15mg/kg, which is among the lowest reported siRNA concentrations, were administered to the animals. About 45% reduction in tumor volume was achieved after 28days in the mice treated with LL2 when compared with the positive control and LL1 treated groups. Thus, our results demonstrate that the 'nano-in-nano' concept of encapsulating poly (l-Lysine) complexed EpCAM siRNA in immunoliposomes may be a promising strategy to treat EpCAM-positive epithelial cancers, especially as an adjuvant therapy.

Comparative docking of dual conformations in human fatty acid synthase thioesterase domain reveals potential binding cavity for virtual screening of ligands.

Human fatty acid synthase (hFASN), a homo dimeric lipogenic enzyme with seven catalytic domains, is an important clinical target in cancer, metabolic syndrome and infections. Here, molecular modelling and docking methods were implemented to examine the inter-molecular interactions of thioesterase (TE) domain in hFASN with its physiological substrate, and to identify potential chemical inhibitors. TE catalyses the hydrolysis of thioester bond between palmitate and the 4' phosphopantetheine of acyl carrier protein, releasing 16-carbon palmitate. The crystal structure of hFASN TE in two inhibitory conformations (A and B) were geometry-optimized and used for molecular docking with palmitate, orlistat (a known FASN inhibitor) and virtual screening against compounds from National Cancer Institute (NCI) database. Relatively, low binding affinity was observed during the complex formation of palmitate with A (-.164 kcal/mol) and B (-.332 kcal/mol) forms of TE, when compared with orlistat-docked TE (A form: -5.872 kcal/mol and B form: -5.484 kcal/mol), clearly indicating that the native inhibited conformation (crystal structure) was unfavourable for substrate binding. We used these orlistat dual binding modes as positive controls for prioritizing the ligands during virtual screening. From 2, 31,617 molecules in the NCI database, 916 high-scoring compounds (hit ligands) were obtained for A-form and 4582 for B-form of the TE-domain, which were then ranked according to glide docking score, XP H bond score, absorption, distribution, metabolism and excretion and binding free energy (Prime/MM-GBSA). Consequently, two top scoring ligands (NSC: 319661 and NSC: 153166) emerged as promising drug candidates that may be tested in FASN-over-expressing diseases.

Orbital angioleiomyoma: A rare orbital neoplasm.

A 44-year-old male patient presented with painless progressive proptosis of left eye for the last 20 years. Examination revealed a purplish vascular mass extending from the medial orbital region to the surface of the globe. He underwent complete excision of the mass via an anterior orbitotomy approach. Histopathology and immunohistochemistry revealed a diagnosis of angioleiomyoma. No recurrence was noted at 1 year of follow-up. Angioleiomyomas are benign smooth muscle tumors with an additional vascular component. Their occurrence in the orbit is extremely rare with only three cases reported in literature till date. We report a fourth case of angioleiomyoma of the orbit with the longest duration of presentation of 20 years.

EpCAM-targeted liposomal si-RNA delivery for treatment of epithelial cancer.

BACKGROUND: RNA interference (RNAi) technology using short interfering RNA (si-RNA) has shown immense potential in the treatment of cancers through silencing of specific genes. Cationic non-viral vectors employed for gene delivery exhibit toxic effects in normal cells limiting their widespread use, therefore, site-specific delivery using benign carriers could address this issue. OBJECTIVE: Design of a non-toxic carrier that enables site-specific delivery of si-RNA into the cancer cells is of prime importance to realize the promise of gene silencing. METHODS: In the present study, non-cationic liposomes encapsulating si-RNA against epithelial cell adhesion molecule (EpCAM) were developed and characterized for encapsulation efficiency, colloidal stability, in vitro and in vivo gene silencing efficacy. RESULTS: PEGylated liposomes containing phosphatidyl choline and phosphatidyl ethanolamine exhibited maximum si-RNA encapsulation efficiency of 47%, zeta potential of -21 mV, phase transition temperature of 51 °C and good colloidal stability in phosphate-buffered saline (PBS) containing bovine serum albumin (BSA) and plasma protein (PP) at 37 °C. Conjugation of epithelial cell adhesion molecule (EpCAM) antibody to the liposomes resulted in enhanced cell internalization and superior down-regulation of EpCAM gene in MCF-7 cell lines when compared with free si-RNA and the non-targeted liposomes. In vivo evaluation of immunoliposomes for their efficacy in regressing the tumor volume in Balb/c SCID mice showed about 35% reduction of tumor volume in comparison with the positive control when administered with an extremely low dose of 0.15 mg/kg twice a week for 4 weeks. CONCLUSION: Our results exhibit that the nanocarrier-mediated silencing of EpCAM gene is a promising strategy to treat epithelial cancers.