Injectable in situ cross-linking hyaluronan hydrogel for easier removal of posterior vitreous cortex in vitrectomy.

PURPOSE: Removing transparent vitreous tissues, such as a residual vitreous cortex (VC) or proliferative membrane, without damaging the retina is often problematic in vitrectomy. We examined the feasibility of an injectable in situ cross-linking hyaluronan hydrogel (XL-HA) for vitrectomy. STUDY DESIGN: Experiments using ex vivo and in vivo animal models. METHODS: HA-dibenzocyclooctyne and HA-azidoethylamine solutions were mixed to form XL-HA, which then gradually formed a hydrogel. We tested the function of XL-HA in ex vivo porcine eyes. We then examined the performance of XL-HA in in vivo rabbit models of posterior vitreous detachment, posterior VC removal, and proliferative vitreoretinopathy. RESULTS: The ex vivo study showed that XL-HA rapidly embedded triamcinolone acetonide, mimicking VC attached to the retina, and became hard enough to be pinched with tweezers within 3 minutes, allowing us to remove only the triamcinolone acetonide without impairing the internal limiting membrane. In the in vivo rabbit models, XL-HA injection improved posterior vitreous detachment, and the thin and fragile posterior VC or fibrous proliferative membrane was readily peeled off without any damage to the underlying retina as compared with untreated controls. A short-term intraocular biocompatibility test demonstrated that the intraocular pressure remained normal with XL-HA injected into the eye. In addition, transmission electron microscopy showed no obvious abnormalities in the cornea or in the inner and outer retina. CONCLUSION: The results indicate that XL-HA is a potential adjunctive device to help make vitrectomy safe, effective, and successful.

Perfil das mulheres vítimas de agressão pelo parceiro, atendidas no Instituto Médico Legal / Profile of women assault victims treated at the Medical Legal Institute

Objetivo: caracterizar o perfil das mulheres vítimas de agressão física pelo seu ex-parceiro, atendidas noCentro de Perícias Renato Chaves-Belém-Pará. Método: pesquisa prospectiva, com estudo descritivo eestatístico do perfil populacional através da aplicação de um questionário. A casuística foi constituída por160 mulheres, com o intervalo de confiança de 95% e um erro padrão de 6,15%. Conclusão: as mulheresvítimas de agressão apresentaram faixa etária entre 18 a 29 anos, ensino fundamental incompleto, sendo odistrito administrativo do Benguí o mais frequente, trabalhavam como autônomas, possuíam residênciaprópria, com mais de três moradores, tendo de um a dois filhos e recebendo menos de um salário.

Objective: characterize the profile of women victims of physical assault by his (ex) partner, at the Centerof Expertise Renato Chaves-Belém-Pará. Method: prospective, performing a statistical study descriptiveprofile of the population through a questionnaire. The sample consisted of 160 women, with a confidenceinterval of 95% and a standard error of 6.15%. Conclusion: women victims of aggression presented aged18 to 29 years, elementary school, worked as autonomous and had their own home, with more than threeresidents, and the district's administrative Bengui the most frequent, having one or two children , earningless than one salary.

Therapeutic chaperone effect of N-octyl 4-epi-ß-valienamine on murine G(M1)-gangliosidosis.

Therapeutic chaperone effect of a valienamine derivative N-octyl 4-epi-ß-valienamine (NOEV) was studied in G(M1)-gangliosidosis model mice. Phamacokinetic analysis revealed rapid intestinal absorption and renal excretion after oral administration. Intracellular accumulation was not observed after continuous treatment. NOEV was delivered to the central nervous system through the blood-brain barrier to induce high expression of the apparently deficient ß-galactosidase activity. NOEV treatment starting at the early stage of disease resulted in remarkable arrest of neurological progression within a few months. Survival time was significantly prolonged. This result suggests that NOEV chaperone therapy will be clinically effective for prevention of neuronal damage if started early in life hopefully also in human patients with G(M1)-gangliosidosis.

Lysosomal accumulation of Trk protein in brain of GM1 -gangliosidosis mouse and its restoration by chemical chaperone.

G(M1) -gangliosidosis is a fatal neurodegenerative disorder caused by deficiency of lysosomal acid ß-galactosidase (ß-gal). Accumulation of its substrate ganglioside G(M1) (G(M1) ) in lysosomes and other parts of the cell leads to progressive neurodegeneration, but underlying mechanisms remain unclear. Previous studies demonstrated an essential role for interaction of G(M1) with tropomyosin receptor kinase (Trk) receptors in neuronal growth, survival and differentiation. In this study we demonstrate accumulation of G(M1) in the cell-surface rafts and lysosomes of the ß-gal knockout (ß-gal-/-) mouse brain association with accumulation of Trk receptors and enhancement of its downstream signaling. Immunofluorescence and subcellular fractionation analysis revealed accumulation of Trk receptors in the late endosomes/lysosomes of the ß-gal-/- mouse brain and their association with ubiquitin and p62. Administration of a chemical chaperone to ß-gal-/- mouse expressing human mutant R201C protein resulted in a marked reduction of intracellular storage of G(M1) and phosphorylated Trk. These findings indicate that G(M1) accumulation in rafts causes activation of Trk signaling, which may participate in the pathogenesis of G(M1) -gangliosidosis.

Chemical chaperone therapy: chaperone effect on mutant enzyme and cellular pathophysiology in ß-galactosidase deficiency.

ß-Galactosidase deficiency is a group of lysosomal lipid storage disorders with an autosomal recessive trait. It causes two clinically different diseases, G(M1) -gangliosidosis and Morquio B disease. It is caused by heterogeneous mutations in the GLB1 gene coding for the lysosomal acid ß-galactosidase. We have previously reported the chaperone effect of N-octyl-4-epi-ß-valienamine (NOEV) on mutant ß-galactosidase proteins. In this study, we performed genotype analyses of patients with ß-galactosidase deficiency and identified 46 mutation alleles including 9 novel mutations. We then examined the NOEV effect on mutant ß-galactosidase proteins by using six strains of patient-derived skin fibroblast. We also performed mutagenesis to identify ß-galactosidase mutants that were responsive to NOEV and found that 22 out of 94 mutants were responsive. Computational structural analysis revealed the mode of interaction between human ß-galactosidase and NOEV. Moreover, we confirmed that NOEV reduced G(M1) accumulation and ameliorated the impairments of lipid trafficking and protein degradation in ß-galactosidase deficient cells. These results provided further evidence to NOEV as a promising chaperone compound for ß-galactosidase deficiency.

Chemical chaperone therapy: luciferase assay for screening of ß-galactosidase mutations.

ß-Galactosidosis is a group of disorder based on heterogeneous mutations of GLB1 gene coding for the lysosomal acid ß-galactosidase (ß-gal). A decrease of the ß-gal enzyme activity results in progressive accumulation of substrates in somatic cells, particularly in neurons, leading to severe neuronal dysfunction. We have previously reported that N-octyl-4-epi-ß-valienamine (NOEV), a chemical chaperone compound, stabilized various mutant human ß-gal proteins and increased residual enzyme activities in cultured fibroblasts from human patients. These data proved a potential therapeutic benefit of chemical chaperone therapy for patients with missense ß-gal. This effect is mutation specific. In this study, we have established a sensitive luciferase-based assay for measuring chaperone effect on mutant human ß-gal. A dinoflagellate luciferase (Dluc) cDNA was introduced to the C-terminus of human ß-gal. When COS7 cells expressing the Dluc-tagged human R201C ß-gal was treated with NOEV, there happened a remarkable increase of the mutant ß-gal activity. In the presence of NH(4)Cl, luciferase level in the medium increased in parallel with the enzyme activity in cell lysates. We also found that proteasome inhibitors enhance chaperone effect of NOEV. These results demonstrate that the luciferase-based assay is a reliable and convenient method for screening and evaluation of chaperone effects on human ß-gal mutants, and that it will be a useful tool for finding novel chaperone compounds in the future study.

The effect of N-octyl-ß-valienamine on ß-glucosidase activity in tissues of normal mice.

Gaucher disease (GD), mainly caused by a defect of acid ß-glucosidase (ß-Glu), is the most common sphingolipidosis. We have previously shown that a carbohydrate mimic N-octyl-ß-valienamine (NOV), an inhibitor of ß-Glu, could increase the protein level and enzyme activity of various mutant ß-Glu in cultured GD fibroblasts, suggesting that NOV acted as a pharmacological chaperone to accelerate transport and maturation of this mutant enzymes. In the present study, the NOV effect was evaluated for ß-Glu activity, tissue distribution and adverse effects in normal mice. We measured the ß-Glu activity in tissues of normal mice which received water containing increasing concentrations of NOV ad libitum for 1 week. Fluid intake and body weight were measured periodically throughout the study. Measurement of tissue NOV concentration, blood chemistry and urinalysis were performed at the end of the study. The results showed that NOV had no impact on the body weight but fluid intake in the 10mM NOV group mice decreased and there was a moderate increase in blood urea nitrogen (BUN). No other adverse effect was observed during this experiment. Tissue NOV concentration increased in all tissues examined with increasing NOV doses. No inhibitory effect of NOV on ß-Glu was observed. Furthermore, NOV increased the ß-Glu activity in the liver, spleen, muscle and cerebellum of the mice significantly. This study on NOV showed its oral availability and wide tissue distribution, including the brain and its lack of acute toxicity. These characteristics of NOV would make it a potential therapeutic chaperone in the treatment of GD with neurological manifestations and selected mutations.

The pharmacological chaperone effect of N-octyl-beta-valienamine on human mutant acid beta-glucosidases.

Gaucher's disease (GD), mainly caused by a defect of acid beta-glucosidase (beta-Glu), is the most common form of sphingolipidosis. We have previously shown that the carbohydrate mimic and inhibitor of beta-Glu, N-octyl-beta-valienamine (NOV), could increase the protein level and enzyme activity of various mutant beta-Glus in cultured GD fibroblasts and in COS cells, suggesting that NOV acts as a pharmacological chaperone to accelerate transport and maturation of these mutant enzymes. In present study, we continued to investigate the chaperone characteristics of NOV. More importantly, chaperone activities of NOV were evaluated in COS cells transiently expressing ten new, recombinant beta-Glu mutants with mutations located in domain I, II and III. NOV was only effective on the T369M mutation, located in domain III. As we suggested in a previous study, domain III may be a prerequisite for pharmacological rescue of the mutant beta-Glu by NOV. These characteristics of NOV could provide potential therapeutic chaperone properties that would be useful in the treatment of GD with neurological manifestations due to gene mutations in beta-Glu.

Chemical chaperone therapy: clinical effect in murine G(M1)-gangliosidosis.

Certain low-molecular-weight substrate analogs act both as in vitro competitive inhibitors of lysosomal hydrolases and as intracellular enhancers (chemical chaperones) by stabilization of mutant proteins. In this study, we performed oral administration of a chaperone compound N-octyl-4-epi-beta-valienamine to G(M1)-gangliosidosis model mice expressing R201C mutant human beta-galactosidase. A newly developed neurological scoring system was used for clinical assessment. N-Octyl-4-epi-beta-valienamine was delivered rapidly to the brain, increased beta-galactosidase activity, decreased ganglioside G(M1), and prevented neurological deterioration within a few months. No adverse effect was observed during this experiment. N-Octyl-4-epi-beta-valienamine will be useful for chemical chaperone therapy of human G(M1)-gangliosidosis.

Enzyme enhancement activity of N-octyl-beta-valienamine on beta-glucosidase mutants associated with Gaucher disease.

Gaucher disease (GD), caused by a defect of beta-glucosidase (beta-Glu), is the most common form of sphingolipidosis. We have previously shown that a carbohydrate mimic N-octyl-beta-valienamine (NOV), an inhibitor of beta-Glu, could increase the protein level and enzyme activity of F213I mutant beta-Glu in cultured GD fibroblasts, suggesting that NOV acted as a pharmacological chaperone to accelerate transport and maturation of this mutant enzyme. In the current study, NOV effects were evaluated in GD fibroblasts with various beta-Glu mutations and in COS cells transiently expressing recombinant mutant proteins. In addition to F213I, NOV was effective on N188S, G202R and N370S mutant forms of beta-Glu, whereas it was ineffective on G193W, D409H and L444P mutants. When expressed in COS cells, the mutant proteins as well as the wild-type protein were localized predominantly in the endoplasmic reticulum and were sensitive to Endo-H treatment. NOV did not alter this localization or Endo-H sensitivity, suggesting that it acted in the endoplasmic reticulum. Profiling of N-alkyl-beta-valienamines with various lengths of the acyl chain showed that N-dodecyl-beta-valienamine was as effective as NOV. These results suggest a potential therapeutic value of NOV and related compounds for GD with a broad range of beta-Glu mutations.

Fibroblast screening for chaperone therapy in beta-galactosidosis.

We performed screening of beta-galactosidase-deficient fibroblasts for possible chemical chaperone therapy using N-octyl-4-epi-beta-valienamine (NOEV) in patients with GM1-gangliosidosis and Morquio B disease (beta-galactosidosis). Fibroblasts were cultured with NOEV for 4 days and beta-galactosidase activity was measured. Mutation analysis was performed simultaneously. Two separate criteria were set for evaluation of the chaperone effect: a relative increase of enzyme activity (more than 3-fold), and an increase up to more than 10% normal enzyme activity. Among the 50 fibroblast strains tested, more than 3-fold increase was achieved in 17 cell strains (34%), and more than 10% normal activity in 10 (20%). Both criteria were satisfied in 6 (12%), and either of them in 21 (42%). Juvenile GM1-gangliosidosis was most responsive, and then infantile GM1-gangliosidosis. This enhancement was mutation-specific. We estimate that the NOEV chaperone therapy will be effective in 20-40% of the patients, mainly in juvenile and infantile GM1-gangliosidosis patients. A molecular design may produce mutation-specific chaperone compounds for the other disease phenotypes. This cellular screening will be useful for identification of human patients with beta-galactosidase deficiency for chaperone therapy to be started in the near future.

Microscale preparation of even- and odd-numbered N-acetylheparosan oligosaccharides.

In order to prepare a series of N-acetylheparosan (NAH)-related oligosaccharides, bacterial NAH produced in Escherichia coli strain K5 was partially depolymerized with heparitinase I into a mixture of even-numbered NAH oligosaccharides, having an unsaturated uronic acid (DeltaUA) at the non-reducing end. A mixture of odd-numbered oligosaccharides was derived by removing this DeltaUA in the aforementioned mixture by a 'trimming' reaction using mercury(II) acetate. Each oligosaccharide mixture was subjected to gel-filtration chromatography to generate a series of size-uniform NAH oligosaccharides of satisfactory purity (assessed by analytical anion-exchange HPLC), and their structures were identified by MALDITOF-MS, ESIMS, and 1H NMR analysis. As a result, a microscale preparation of a series of both even- and odd-numbered NAH oligosaccharides was achieved for the first time. The developed procedure is simple and systematic, and thus, should be valuable for providing not only research tools for heparin/heparan sulfate-specific enzymes and their binding proteins, but also precursor substrates with medical applications.