Secondary choriocapillaritis in infectious chorioretinitis.

PURPOSE: To analyse the indocyanine green angiography (ICGA) patterns of hypofluorescence that are compatible with choriocapillaritis that occur secondarily to toxoplasmic retinochoroiditis (ToRC), ocular tuberculosis (including tuberculous choroiditis, TuCR and multifocal serpiginoid choroiditis, TMSC) and syphilitic chorioretinitis (SyCR). METHODS: This was a single centre, retrospective case review study. Patients with a diagnosis of ToRC, TuCR, TMSC or SyCR were identified, their charts were reviewed and fundus photographs, fluorescein angiography (FA) and ICGA pictures were assessed. RESULTS: Indocyanine green angiography was performed at the initial presentation in 63 of the 105 patients with ToRC, in 37 of the 38 patients with TuCR, in six of six patients with TMSC and in two of four patients with SyCR. The following four ICGA patterns indicated choriocapillaritis: extension of hypofluorescence beyond the hypofluorescence of the actual infectious focus as seen on fundus photography or FA (seen only in ToRC and TuCR); small dark dots around the infectious focus (seen only in ToRC); multiple 'confetti-like' hypofluorescent areas or hypofluorescent geographical confluent areas (seen only in TMSC); and widespread areas of nonperfusion visible only in ICGA (seen only in SyCR). CONCLUSIONS: Patients with secondary choriocapillaritis have distinct typical ICGA findings. ICGA is thus an important diagnostic tool that can provide an explanation for otherwise obscure visual loss and that might have diagnostic value for specific conditions like ToRC and SyCR.

High-throughput hydrophilic interaction chromatography coupled to tandem mass spectrometry for the optimized quantification of the anti-Gram-negatives antibiotic colistin A/B and its pro-drug colistimethate.

Colistin is a last resort's antibacterial treatment in critically ill patients with multi-drug resistant Gram-negative infections. As appropriate colistin exposure is the key for maximizing efficacy while minimizing toxicity, individualized dosing optimization guided by therapeutic drug monitoring is a top clinical priority. Objective of the present work was to develop a rapid and robust HPLC-MS/MS assay for quantification of colistin plasma concentrations. This novel methodology validated according to international standards simultaneously quantifies the microbiologically active compounds colistin A and B, plus the pro-drug colistin methanesulfonate (colistimethate, CMS). 96-well micro-Elution SPE on Oasis Hydrophilic-Lipophilic-Balanced (HLB) followed by direct analysis by Hydrophilic Interaction Liquid Chromatography (HILIC) with Ethylene Bridged Hybrid - BEH - Amide phase column coupled to tandem mass spectrometry allows a high-throughput with no significant matrix effect. The technique is highly sensitive (limit of quantification 0.014 and 0.006μg/mL for colistin A and B), precise (intra-/inter-assay CV 0.6-8.4%) and accurate (intra-/inter-assay deviation from nominal concentrations -4.4 to +6.3%) over the clinically relevant analytical range 0.05-20μg/mL. Colistin A and B in plasma and whole blood samples are reliably quantified over 48h at room temperature and at +4°C (<6% deviation from nominal values) and after three freeze-thaw cycles. Colistimethate acidic hydrolysis (1M H2SO4) to colistin A and B in plasma was completed in vitro after 15min of sonication while the pro-drug hydrolyzed spontaneously in plasma ex vivo after 4h at room temperature: this information is of utmost importance for interpretation of analytical results. Quantification is precise and accurate when using serum, citrated or EDTA plasma as biological matrix, while use of heparin plasma is not appropriate. This new analytical technique providing optimized quantification in real-life conditions of the microbiologically active compounds colistin A and B offers a highly efficient tool for routine therapeutic drug monitoring aimed at individualizing drug dosing against life-threatening infections.

Lectin receptors distribution in the surface membrane of Trypanosoma cruzi blood forms collected from mice submitted to specific treatment

The author investigated the distribution of lectin receptors on Trypanosoma cruzi blood forms collected from mice inoculated with, respectively, the drug-resistant and drug-sensitive strains VL-10 and CL, and treated with the two standard active nitroheterocyclic compounds nifurtimox and benznidazole used for treatment of human Chagas' disease. Blood trypomastigotes purified in Fycoll-Hypaque were incubated with fluorescein-labelled lectins Con A, WGA, EE, WFA, TPA and PNA and then microscopically examined. Neither qualitative or quantitative differences in the fluorescence intensity could be detected between parasites from VL-10 and CL strains submitted or not to treatment. The results suggest that both strains do not differ in their surface membrane carbohydrate moieties. Moreover, the rapid clearance of blood forms the drug-sensitive strain in animals treated with singlo doses of both compounds is not likely to depend on membrane alterations expressed by changes in the carbohydrate components. furthermore, resistance or sensitivity to drugs is not apparently related to carbohydrate distribution on T. cruzi blood forms.

Some progress on the chemistry of natural bioactive terpenoids form Chinese medicinal plants

(1) Pseudolaric acids - Novel diterpenes, Pseudolaric acid A, B, C and D were isolated from Pseudolarix kaempferi Gorden (pinaceae). Their structures were assigned by spectroscopic data and chemical correlations. In the contineous studies, the absolute configurations, the conformations in the solutions, the framentation mechanisms of MS and assigments of all NMR spectral signals were also reported. They showed the antifungal and cytotoxic activities. (2) Daphnane diterpenes - In the further studies on the plants of Thymelaeaceae, besides 10 known diterpenes, 16 new daphnane diterpenes were isolated from Daphne genkwa, D. tangutica, D. giraldii, Wikstroemie chamaedaphne. They showed the antifertilities activities. (3) Tripterygium diterpenes 14 new diterpenes were isolated from Triperygium wilfordii, T. regeli and T. hypoglaucum. Some of them showed the antitumor activities. The CD spectra showed that A/B ring of all compoundshave trans configuration as same as tripdiolide and triptolide determined by X-ray diffraction (4) Pregnane glycosides from Marsdenia koi - Two new pregnane glycosides marsdenikoiside A and marsdenikoiside B which can terminate the early pregnancy were isolated from Marsdeia koi. Their structures were elucidated by hydrolysis and spectroscopic methods.

Severe occlusive vasculitis as a complication of cat scratch disease

BACKGROUND: The purpose of this communication is to report a severe occlusive vasculitis as a complication of cat scratch. HISTORY AND SIGNS: A 34-year-old Hispanic woman presented with a sudden visual loss of the right eye associated with shivers, high fever and arthritis which developed 2 months after a cat's bite. Fundus examination showed papillitis and a palor of the paramacular zone of the retina. Fluorescein angiography revealed multiple arterial and venous vasculitic occlusions. THERAPY AND OUTCOME: Auto-immune disease and endocarditis were ruled out by an extensive medical work-up.The diagnosis of Bartonella henselae was confirmed by a positive serology. A systemic antibiotherapy with azithromycin, doxycyclin, rifampicin and steroid therapy resulted in a good clinical response, including a rapid visual recovery with a visual acuity of 20/20 and no relapse of the disease at 6 months follow-up. CONCLUSIONS: Ocular complications associated with cat scratch disease may include vasculitis with both arterial and venous occlusions causing severe visual loss.

Amino acid identity and/or position determines the proteasomal cleavage of the HLA-A*0201-restricted peptide tumor antigen MAGE-3271-279.

The proteasome plays a crucial role in the proteolytic processing of antigens presented to T cells in the context of major histocompatibility complex class I molecules. However, the rules governing the specificity of cleavage sites are still largely unknown. We have previously shown that a cytolytic T lymphocyte-defined antigenic peptide derived from the MAGE-3 tumor-associated antigen (MAGE-3(271-279), FLWGPRALV in one-letter code) is not presented at the surface of melanoma cell lines expressing the MAGE-3 protein. By using purified proteasome and MAGE-3(271-279) peptides extended at the C terminus by 6 amino acids, we identified predominant cleavages after residues 278 and 280 but no detectable cleavage after residue Val(279), the C terminus of the antigenic peptide. In the present study, we have investigated the influence of Pro(275), Leu(278), and Glu(280) on the proteasomal digestion of MAGE-3(271-285) substituted at these positions. We show that positions 278 and 280 are major proteasomal cleavage sites because they tolerate most amino acid substitutions. In contrast, the peptide bond after Val(279) is a minor cleavage site, influenced by both distal and proximal amino acid residues.

In silico prediction of human carboxylesterase-1 (hCES1) metabolism combining docking analyses and MD simulations.

Metabolic problems lead to numerous failures during clinical trials, and much effort is now devoted in developing in silico models predicting metabolic stability and metabolites. Such models are well known for cytochromes P450 and some transferases, whereas little has been done to predict the hydrolytic activity of human hydrolases. The present study was undertaken to develop a computational approach able to predict the hydrolysis of novel esters by human carboxylesterase hCES1. The study involves both docking analyses of known substrates to develop predictive models, and molecular dynamics (MD) simulations to reveal the in situ behavior of substrates and products, with particular attention being paid to the influence of their ionization state. The results emphasize some crucial properties of the hCES1 catalytic cavity, confirming that as a trend with several exceptions, hCES1 prefers substrates with relatively smaller and somewhat polar alkyl/aryl groups and larger hydrophobic acyl moieties. The docking results underline the usefulness of the hydrophobic interaction score proposed here, which allows a robust prediction of hCES1 catalysis, while the MD simulations show the different behavior of substrates and products in the enzyme cavity, suggesting in particular that basic substrates interact with the enzyme in their unprotonated form.

Bilateral uveal pigmented alterations with remarkable evolution: long term follow-up in a case of possible bilateral diffuse uveal melanocytic proliferation

Purpose: to describe a case of probable bilateral diffuse uveal melanocytic proliferation (BDUMP) with scleral involvement, free from systemic malignancies and cataract. Methods: fifty months of follow up with recurrent complete ophthalmological examinations, including fundus photography, fluorescein/indocyanine green angiography (FA) and optical coherence tomography (OCT). Investigations also included an electroretinography (ERG) and histological examination of scleral biopsy. Extraocular malignancies were repeatedly searched. Results: the patient was a 61 year-old Italian man with chronic hepatitis type C. At first visit his best corrected visual acuity (BCVA) was 20/32 in OS and 20/25 in OD. Funduscopy showed multiple patch-shaped pigmented alterations involving macular region and mid retinal periphery. FA showed corresponding areas of late-phase hyperfluorescent pinpoints (figure 1a, OS) and intemediate-phase hypocyanescence (figure 1b, OS), with subtle serous neurosensory retinal detachment confirmed by OCT. Photopic and scotopic ERG tested normal. Systemic prednisone was administered for one month without any improvement. After ten months round pigmentary lesions appeared also in superior scleral surface of both eyes. Biopsy allowed to disclose slightly pigmented spindle cells. BCVA worsened for further 10 months, with enlargement of FA alteration areas but lenses still clear. After 30 months spontaneous coalescence and atrophy of retinal lesions started, paralleled by progressive visual recovery. At the end of our follow up BCVA was 20/25 in OU while scleral pigmentary lesions remained unchanged. Conclusions: we report the case of a patient with main features of BDUMP and some unusual findings. Although not all classical diagnostic criteria were fulfilled, the presence of scleral pigmented lesions and spontaneous visual recovery may enlarge clinical spectrum of the disease.

Anomalies et complications vasculaires dans les drusen du nerf optique [Vascular anomalies and complications of optic nerve drusen]

BACKGROUND: Drusen of the optic disc are associated with slowly progressive optic neuropathy, characterized by accumulation of acellular laminated concretions in the prelaminar portion of the optic nerve. Papillary hemorrhages and vascular shunts have been reported with disc drusen but their frequency and clinical significance is not well known. METHODS: Retrospective study of fundus photographs of 116 patients with disc drusen referred to the National Hospital for Neurology and Neurosurgery, London, between 1965 and 1991. RESULTS: Hemorrhages were found in 23 eyes from 16/116 (13.8%) patients. Most cases (68.8%, 11/16 cases) occurred in patients with buried drusen, and most hemorrhages were deeply located. Vascular shunts were present in 6.9% (8/116 cases), most frequently in patients with exposed drusen (6/8 cases), most being of the venous type (7/8 cases). DISCUSSION: Vascular anomalies are not rare in disc drusen, as 20.7% (24/116 cases) of our patients presented either disc hemorrhages or shunt vessels. Their presence supports the hypothesis of the slowly progressive nature of disc drusen and the more advanced stage of optic neuropathy in such eyes.

Peripheral exudative hemorrhagic chorioretinopathy: a clinical, angiographic, and histologic study.

PURPOSE: To describe the clinical and angiographic characteristics of peripheral exudative hemorrhagic chorioretinopathy, an uncommon chorioretinal mass lesion, important for its differential diagnosis to choroidal melanoma, but only rarely described in the literature. DESIGN: Retrospective, institutional chart review. METHODS: Institutional chart review of 45 patients (56 eyes) diagnosed with peripheral exudative hemorrhagic chorioretinopathy to describe the clinical findings and those obtained by fluorescein angiography (FA) and indocyanine green angiography (ICGA), in addition to a review of the histologic findings of an enucleated eye. RESULTS: Peripheral exudative hemorrhagic chorioretinopathy typically was characterized by increased age of the patient (mean, 77 years; range, 60 to 91 years), female preponderance (69%), frequent pigment epithelium detachment, temporal equatorial location, and a highly hemorrhagic and exudative presentation, sometimes extending to the macula. Bilateral involvement (24%) was associated with multiples lesions in the same eye (P < .001) and with nasal extension (P < .001). A neovascular origin was suspected on FA, but was more evident on ICGA. Histologic examination of the enucleated eye did not reveal a neovascular network. CONCLUSIONS: Peripheral exudative hemorrhagic chorioretinopathy is a characteristic peripheral degenerative disorder, frequently with benign outcome, although it can be vision threatening because of hemorrhage or exudation. Clinical features are helpful for its diagnosis. FA and ICGA contribute valuable evidence to the hypothesis of a neovascular origin, but further histologic studies are needed to prove this hypothesis.

FtsK Is a DNA motor protein that activates chromosome dimer resolution by switching the catalytic state of the XerC and XerD recombinases.

FtsK acts at the bacterial division septum to couple chromosome segregation with cell division. We demonstrate that a truncated FtsK derivative, FtsK(50C), uses ATP hydrolysis to translocate along duplex DNA as a multimer in vitro, consistent with FtsK having an in vivo role in pumping DNA through the closing division septum. FtsK(50C) also promotes a complete Xer recombination reaction between dif sites by switching the state of activity of the XerCD recombinases so that XerD makes the first pair of strand exchanges to form Holliday junctions that are then resolved by XerC. The reaction between directly repeated dif sites in circular DNA leads to the formation of uncatenated circles and is equivalent to the formation of chromosome monomers from dimers.

Intravitreal Ranibizumab in the Treatment of Predominantly Hemorrhagic Lesions in Exudative Age-Related Macular Degeneration.

BACKGROUND: Submacular hemorrhage is a manifestation of neovascular age-related macular degeneration (AMD) that has a very poor natural history leading to severe visual loss. We have evaluated the safety and efficacy of intravitreal ranibizumab in the treatment of predominantly hemorrhagic AMD. PATIENTS AND METHODS: A retrospective study of patients with predominantly hemorrhagic AMD treated with intravitreal ranibizumab at the Jules Gonin Eye Hospital between December 2006 and December 2008 was undertaken. Baseline and monthly follow-up exams included visual acuity (VA), fundus exam and optical coherence tomography (OCT) while fluorescein and indocyanine green angiography were performed at least every three months. RESULTS: The study included 8 eyes. The mean follow-up was 13 months (SD: 6.3). The mean number of intravitreal injections administered for each patient was 6.4 (SD: 2). 50 % of the patients demonstrated stable or improved VA. The size of hemorrhage at baseline was inversely correlated to the final VA (two-tailed p value = 0.038) and positively correlated to the final central macular thickness (two-tailed p value = 0.021). Anticoagulation treatment was inversely correlated to the time of hemorrhage resolution (two-tailed p value = 0.039). CONCLUSIONS: Intravitreal ranibizumab may be an effective treatment for predominantly hemorrhagic lesions due to neovascular AMD.

Three Generation Family With Pattern Dystrophy and a Successful Treatment of Subfoveal Cnv Related to Pattern Dystrophy With Anti-vegf Intravitreal Injections

Purpose: To phenotype a large 3 generation Swiss family with pattern dystrophy and to report a successful result of treatment with ranibizumab of a subfoveal choroidal neovascularisation (CNV) associated with pattern dystrophy in 1 patient Patients and methods: 4 affected and 3 unaffected patients (3 female 4 male, age range: 19 - 80 years) were assessed with a complete ophthalmologic examination. AF images were taken using Heidelberg Retina Angiograph and the digital color photos, fluorescein angiogragraphy (FFA) using the same TOPCON 501 camera. Electroretinogram (full-field and multifocal) was performed in 1 affected patient. One 48 years old patient developed a subfoveal CNV, which was treated with 2 injections of ranibizumab, at 3 months interval. Blood sample was taken for molecular analysis (screening of the gene RDS). Results: Two patients had a typical fundoscopic appearance of pattern dystrophy with butterfly shaped deposit at the fovea and some peripheral flecks, as shown with AF imaging.. Two others affected patients had a more unusual appearance with some macular atrophy in one or both eyes, surrounded by flecks. The visual acuity ranged from 1.0 to 0.1 according to Snellen EDTRS chart. The patient with subfoveal CNV presented a drop of vision form 1.0 to 0.6 within 10 days prior to the diagnosis and also reported some metamorphopsia. FFA and optical computerized tomography (OCT) confirmed a classic CNV. After the 1st injection her vision improved to 1.0 but persistent metamorphopsia and fluid on OCT motivated a second injection. One month after the second injection the OCT was flat and the patient had no symptoms. The results of RDS screening will be presented at the meeting. Conclusion: We present a family with pattern dystrophy, with some members having an unusual fundus appearance, which was mistaken for an early onset dry AMD. The AF imaging is a useful tool in diagnosing this condition. A CNV associated with pattern dystrophy a rare. This is the first report of a successful treatment of the CNV with anti-VEGF intravitreal injections.

Truncation of the receptor carboxyl terminus impairs agonist-dependent phosphorylation and desensitization of the alpha 1B-adrenergic receptor.

The alpha 1B-adrenergic receptor (alpha 1BAR) and its truncated mutant T368 lacking the last 147 amino acids were stably expressed in Rat1 fibroblasts. The wild type alpha 1BAR was rapidly phosphorylated upon exposure to the agonist epinephrine as well as to phorbol ester as assessed by immunoprecipitation of the receptor with antiserum raised against its amino-terminal portion. Exposure of cells expressing the wild type alpha 1BAR to epinephrine resulted also in rapid homologous desensitization of receptor-mediated response on polyphosphoinositide hydrolysis. On the other hand, truncation of the serine- and threonine-rich carboxyl portion of the alpha 1BAR abolished agonist-induced phosphorylation and greatly impaired homologous desensitization of the receptor. The truncated receptor T368 could undergo agonist-induced decrease of cell surface receptors but to a lesser extent, as compared with the wild type alpha 1BAR. These results demonstrate that the carboxyl portion of the alpha 1BAR plays a crucial role in the regulation of receptor function. They also suggest a strong relationship between agonist-induced phosphorylation and desensitization of the alpha 1BAR, which were both insensitive to the inhibitor of protein kinase C RO-318220. Our findings support the emerging hypothesis that the biochemical mechanisms involved in rapid agonist-dependent regulation of G protein-coupled receptors, which activate polyphosphoinositide hydrolysis, do not primarily involve protein kinase C.