Delayed-onset postoperative endophthalmitis secondary to Exophiala

Exophiala is a genus of slow-growing, melanin-producing, saprophytic fungi most commonly found in soil, faeces and decaying plant matter. It is an unusual fungal pathogen capable of causing a variety of ophthalmic manifestations, including keratitis, scleritis and endophthalmitis. In this report, we present a rare case of delayed-onset postoperative endophthalmitis confined to the anterior segment, secondary to Exophiala species. Previous reported cases of delayed-onset postoperative endophthalmitis have been treated medically, with suboptimal outcomes. Our experience supports the use of anterior segment surgery to clear the nidus of disease combined with intravitreal voriconazole to prevent recurrence of the infection.

[Conjunctival impression cytology in patients with normal and impaired OSDI scores]

PURPOSE

To describe goblet cell density and Nelson grading in different areas of the ocular surface using conjunctival impression cytology (CIC) among patients with normal and impaired Ocular Surface Disease Index (OSDI) scores.

MATERIAL AND METHODS

Patients (n=166) under assessment for dry eye were recruited between 2011 and 2012 and classified according to the OSDI score in 4 categories (normal and impaired). Cytological study (CIC plus Papanicolaou staining) using the Nelson grading system, with modifications in staging, and goblet cell counting were performed on the nasal, temporal, inferior, and superior bulbar conjunctival surfaces.

RESULTS

Nelson grading was significantly higher in patients with a severely impaired OSDI score (1.41±0.14) compared to normal patients (0.86±0.09) (P<.01). Goblet cell density was significantly reduced in patients with a severely impaired OSDI score (310.24±56.24 cells per sample) compared with normal subjects (497.31±50.07 cells per sample) (P<.001). Compared with the photoexposed bulbar conjunctiva, goblet cell density on the non-photoexposed conjunctiva was significantly higher both in patients with mild (P<.01) and moderate (P<.001) OSDI scores.

CONCLUSION

Patients with severely impaired OSDI scores have less goblet cells and a higher Nelson grade. Goblet cells are more abundant on the non-photoexposed conjunctiva.

Dynamics of tear fluid desiccation on a glass surface: a contribution to tear quality assessment

BACKGROUND

Fern-like crystalloids form when a microvolume of tear is allowed to dry out at ambient conditions on a glass surface. Presence of crystalloids in tear "microdesiccates" is used to evaluate patients with Dry-Eye disease. This study aims to examine morphologically the desiccation process of normal tear fluid and to identify changes associated with accelerated tear evaporation. Tear microdesiccates from healthy (Non-Dry Eye) and Dry Eye subjects were produced at ambient conditions. Microdesiccate formation was monitored continuously by dark-field video microscopy. Additionally, accelerated desiccation of tear samples from healthy subjects was conducted under controlled experimental conditions. Particular morphological domains of tear microdesiccates and their progressive appearance during desiccation were compared.

RESULTS

In normal tear microdesiccates, four distinctive morphological domains (zones I, II, III and transition band) were recognized. Stepwise formation of those domains is now described. Experimentally accelerated desiccation resulted in marked changes in some of those zones, particularly involving either disappearance or size reduction of fern-like crystalloids of zones II and III. Tear microdesiccates from Dry Eye subjects may also display those differences and be the expression of a more synchronous formation of microdesiccate domains.

CONCLUSION

Morphological characteristics of tear microdesiccates can provide insights into the relative rate of tear evaporation.

Management of subluxated lens in young patients

OBJECTIVES

To evaluate visual outcomes in patients treated for lens subluxation. Secondary objectives are to report best corrected visual acuity (BCVA) in LogMAR and compare the outcomes of patients managed conservatively with those treated surgically.

METHODS

Retrospective comparison of BCVA in patients under 50 years-old with lens subluxation, managed conservatively or surgically.

RESULTS

A total of 49 eyes of 28 patients were included. Demographic characteristics were similar in both groups. Twenty eyes were treated surgically (40.8%) compared to 29 with medical treatment (59.2%). Marfan syndrome (79.6%) was diagnosed in 39 eyes. LogMAR BCVA post intervention was 0.35±0.31 for medical treatment and 0.39±0.32 for the surgical group, with no significant differences (P=.63). Improvements in LogMAR lines were 2.7±4.2 and 4.11±4.2 (P=.35), respectively. Two eyes in the surgery group developed ocular hypertension (0.04%), none with retinal detachment.

CONCLUSIONS

The final BCVA showed no significant differences in this group of patients. BCVA depends on the visual potential of the rehabilitated eye rather than a specific type of intervention.

Frequent Evaluation To Improve Compliance In Patients Treated With Occlusion For Amblyopia: A Randomized controlled Trial

BACKGROUND

The benefits of occlusion treatment for amblyopia are well established.True compliance can be difficult to assess and is usually based on patient history. We hypothesize that more visits to the physician provides more chances to improve compliance.

METHODS

We conducted a prospective, comparative, blind trial in which 30 children with amblyopia were randomly assigned to be followed up more frequently (every 4 to 6 weeks) (study group) or as established on our standard regular basis (month intervals based on age in years) (control group). The primary outcome was to study differences in treatment compliance between these groups. The secondary outcome was to report compliance in a group of Chilean children and to compare survey results with adherence, to assess concordance between them.

RESULTS

Baseline clinical characteristics were similar in the two groups. 30 patients were recruited. Mean compliance for all patients was 82%. Study group compliance was 83% versus 76% in control group (p = 0.5). Without epidemiology, intention to treat analysis (ITT), study group compliance was 97% compared to 76% in control group (p = 0.049). Pearson correlation between negative responses to a parental survey after treatment, of the percentage of adherence and compliance, was -0.57 and statistically significant (p = 0.013).

CONCLUSIONS

There were no differences in patient compliance comparing more frequent evaluation versus a follow up evaluation based in an age according scheme. There is a high compliance to occlusion therapy in this group of Chilean children. If parents reported more negative adherence aspects in the survey, the worse the compliance.

Involvement of the transcription factor STAT1 in the regulation of porcine ovarian granulosa cell functions treated and not treated with ghrelin

The aim of our in vitro experiments was to study the role of the transcription factor STAT1 and the hormone ghrelin in controlling porcine ovarian function. The effects of treatment with ghrelin (0, 1, 10, 100 ng/ml), transfection-induced overexpression of transcription factor STAT1, and their combination on apoptosis (expression of apoptosis-related peptides caspase-3, BAX and anti-apoptotic peptide BCL2), proliferation (expression of proliferating cell nuclear antigene PCNA, proliferation-associated protein kinase MAPK/ERK1,2) and release of the hormones progesterone (P(4)), prostaglandin F (PGF) and oxytocin (OXT) in cultured porcine ovarian granulosa cells was evaluated using RIA, immunocytochemistry and SDS-PAGE-western immunoblotting. It was found that ghrelin, when given alone, increased the expression of proliferation-associated PCNA and MAPK/ERK1,2, decreased the accumulation of apoptosis-related substances caspase-3, BAX, BCL2, decreased P(4), and increased PGF and OXT release. Ghrelin tended to promote accumulation of STAT1 in both control and transfected cells, although in transfected cells ghrelin at 1 ng/ml decreased STAT1 accumulation. Transfection of porcine granulosa cells by a gene construct encoding STAT1 promoted the expression of STAT1 and apoptosis-related-BAX but the expression of BCL2 did not, and decreased the accumulation of proliferation-associated MAPK/ERK1,2 but not that of PCNA. It also promoted PGF and OXT but not P(4) release. Overexpression of STAT1 reversed the effect of ghrelin on STAT1, PCNA, PGF, OXT (from stimulatory to inhibitory), BCL2, P(4) (from inhibitory to stimulatory), prevented ghrelin effect on caspase-3 and BAX, but did not affect ghrelin's effect on MAPK/ERK1,2 expression. These results suggest that ghrelin directly affects porcine ovarian cells function - stimulates proliferation, inhibits apoptosis and affects secretory activity. Furthermore, they demonstrated the involvement of the transcription factor STAT1 in controlling these functions, the promotion of some markers of apoptosis (BAX), inhibition of some markers of proliferation (MAPK/ERK1,2) and stimulation of PGF release. Finally, the obtained data failed to demonstrate that STAT1 is involved in mediating the action of ghrelin on ovarian cell functions.

Transcription factor p53 can regulate proliferation, apoptosis and secretory activity of luteinizing porcine ovarian granulosa cell cultured with and without ghrelin and FSH

The aim of our in vitro experiments was to examine the role of transcription factor p53 in controlling the basic functions of ovarian cells and their response to hormonal treatments. Porcine ovarian granulosa cells, transfected and non-transfected with a gene construct encoding p53, were cultured with ghrelin and FSH (all at concentrations of 0, 1, 10, or 100 ng/ml). Accumulation of p53, of apoptosis-related (MAP3K5) and proliferation-related (cyclin B1) substances was evaluated by immunocytochemistry. The secretion of progesterone (P4), oxytocin (OT), prostaglandin F (PGF), and E (PGE) was measured by RIA. Transfection with the p53 gene construct promoted accumulation of this transcription factor within cells. It also stimulated the expression of a marker of apoptosis (MAP3K5). Over-expression of p53 resulted in reduced accumulation of a marker of proliferation (cyclin B1), P4, and PGF secretion and increased OT and PGE secretion. Ghrelin, when added alone, did not affect p53 or P4, but reduced MAP3K5 and increased PGF and PGE secretion. Over-expression of p53 reversed the effect of ghrelin on OT, caused it to be inhibitory to P4 secretion, but did not modify its action on MAP3K5, PGF, or PGE. FSH promoted the accumulation of p53, MAP3K5, and cyclin B1; these effects were unaffected by p53 transfection. These multiple effects of the p53 gene construct on luteinizing granulosa cells, cultured with and without hormones 1) demonstrate the effects of ghrelin and FSH on porcine ovarian cell apoptosis and secretory activity, 2) confirm the involvement of p53 in promoting apoptosis and inhibiting P4 secretion in these cells, 3) provide the first evidence that p53 suppress proliferation of ovarian cells, 4) provide the first evidence that p53 is involved in the control of ovarian peptide hormone (OT) and prostaglandin (PGF and PGE) secretion, and 5) suggest that p53 can modulate, but probably not mediate, the effects of ghrelin and FSH on the ovary.

The effect of obestatin on porcine ovarian granulosa cells

The aim of our in vitro experiments was to investigate the role of obestatin, a newly discovered metabolic hormone produced in the stomach and other tissues, in the direct control of ovarian cell proliferation, apoptosis and secretion. Porcine granulosa cells were cultured in the presence of obestatin (0, 1, 10 and 100ng/ml medium). The expression of intracellular peptides associated with proliferation (PCNA, cyclin B1, MAP kinase), as well as markers of apoptosis (Bax, p53, Caspase 3), were detected using immunocytochemistry and Western immunoblotting. Secretion of progesterone (P4), testosterone (T) and estradiol (E2) was measured by EIA. Addition of obestatin (1-100ng/ml) to the culture medium significantly stimulated the expression of PCNA and resulted in an increase in expression of cyclin B1 and MAPK. It also significantly increased the percentage of cells containing the apoptotic and anti-proliferating peptides p53, Caspase 3 and Bax. At 10 and 100ng/ml, obestatin promoted the secretion of P4, but not T or E2. Our results are the first demonstration that obestatin directly controls porcine ovarian cell functions: it can stimulate proliferation (accumulation of rPCNA, cyclin B1 and MAPK), apoptosis (expression of p53, Caspase 3 and Bax) and the secretion of progesterone.

Some endocrine traits of transgenic rabbits. II. Changes in hormone secretion and response of isolated ovarian tissue to FSH and ghrelin

In the present in vitro experiments we examined FSH- and ghrelin-induced changes in ovarian hormone secretion by transgenic rabbits. Fragments of ovaries isolated from adult transgenic (carrying mammary gland-specific mWAP-hFVIII gene) and non-transgenic rabbits from the same litter were cultured with and without FSH or ghrelin (both at 0, 1, 10 or 100 ng/ml medium). The secretion of progesterone (P4), estradiol (E2) and insulin-like growth factor I (IGF-I) was assessed by RIA. It was observed that ovaries isolated from transgenic rabbits secreted much less P4, E2 and IGF-I than the ovaries of non-transgenic animals. In control animals FSH reduced E2 (at doses 1-100 ng/ml medium) and IGF-I (at 1-100 ng/ml), but not P4 secretion, whereas ghrelin promoted P4 (at 1 ng/ml) and IGF-I (at 100 ng/ml), but not E2 output. In transgenic animals, the effects were reversed: FSH had a stimulatory effect on E2 (at 100 ng/ml) and ghrelin had an inhibitory effect on P4 (at 10 ng/ml). No differences in the pattern of influence of FSH on P4 and IGF-I and of ghrelin on E2 and IGF-I were found between control and transgenic animals. The present observations suggest that 1) both FSH and ghrelin are involved in rabbit ovarian hormone secretion, 2) transgenesis in rabbits is associated with a reduction in ovarian secretory activity, and 3) transgenesis can affect the response of ovarian cells to hormonal regulators.

Optimal length of triple therapy for H pylori eradication in a population with high prevalence of infection in Chile

AIM: To compare the efficacy of 7-d versus 14-d triple therapy for the treatment of H pylori infection in Chile, with a prevalence of 73% in general population.

METHODS: H pylori-infected patients diagnosed by rapid urease test, with non-ulcer dyspepsia or peptic ulcer disease were randomized to receive omeprazole 20 mg bid, amoxicillin 1 g bid, and clarithromycin 500 mg bid for 7 (OAC7) or 14 (OAC14) d. Primary outcome was eradication rate 6 wk after the treatment. Subgroup analysis was carried out considering the eradication rate among patients with or without peptic ulcer disease and eradication rate among smokers or non-smokers.

RESULTS: One hundred and thirty-one patients were randomized to OAC7 (n = 69) or OAC14 (n = 62). The overall eradication rate (intention-to-treat) was 78.3% in OAC7 and 85.5% in OAC14 groups, without a significant difference (P =0.37). No significant difference in the eradication rate was found among the patients with peptic ulcer disease (n = 31) between the OAC7 group (85.7%) and OAC14 group (87.5%). However, smokers had an obviously lower eradication rate compared to non-smokers, particularly in the OAC7 group (57.1% in smokers vs 83.6% in non-smokers; P = 0.06). Adverse effects rate were similar between both groups.

CONCLUSION: Short-term efficacy of triple therapy with OAC for 7 d is comparable to 14 d in this high-prevalence population. Longer follow-up, and studies focused to some subgroups of patients (smokers and non-ulcer patients) are necessary to support widespread use of 7-d instead of 10-14-d triple therapy in a developing country like Chile.

Facile preparation of disulfide-bridged peptides using the polymer-supported oxidant CLEAR-OX

Formation of disulfide bonds in synthetic peptides is one of the more challenging transformations to achieve in peptide chemistry, in view of the possible formation of oligomeric by-products and other side reactions, as well as occasional solubility problems in aqueous oxidizing media. It was shown previously that 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB identical with Ellman's reagent), when attached to polyethylene glycol-polystyrene (PEG-PS), controlled-pore glass (CPG), or modified Sephadex supports, was an effective oxidizing agent that promoted disulfide formation under mild conditions. More recently, this work was extended to Cross-Linked Ethoxylate Acrylate Resin (CLEAR) supports, because of their compatibility with both organic and aqueous solvent mixtures. The resultant new tool, termed CLEAR-OX, was used to conveniently produce several model cyclic disulfides with improved purities and yields, when compared with solution oxidations. A particularly striking example was the gram-scale oxidation of a urotensin II antagonist peptide containing a hindered penicillamine unit.

Study of the influence of the pH media dissolution, degree of polymerization, and degree of swelling of the polymers on the mechanism of release of diltiazem from matrices based on mixtures of chitosan/alginate

The dissolution profiles of formulations based on mixtures of chitosan/alginate depend on the pH. It is possible to distinguish two processes: (a) a fast kinetic drug release up to 180 min, where the pH value changes from 1.17 to 2.21 and the drug released is controlled by the degree of polymerization and the quantity of chitosan in the formulation; (b) a low kinetic drug release between 210 and 480 min, where the pH value changes from 5.52 to 8.72 and the drug release from the matrix is controlled by the interpolymeric complex. In all formulations the order of release, according to Peppas's model in the range of fast kinetic drug release, was between 0.5 and 1.0. The mechanism of release was non-fickian diffusion, which corresponds to a coupling mechanism of diffusion and relaxation of the polymer.