Analysis of macular and nerve fiber layer thickness in multiple sclerosis patients according to severity level and optic neuritis episodes. / Análisis del grosor macular y de capa de fibras nerviosas en pacientes con esclerosis múltiple en relación con su nivel de gravedad y antecedentes previos de neuritis óptica.

INTRODUCTION: Quantitative assessment of macular and nerve fibre layer thickness in multiple sclerosis patients with regard to expanded disability status scale (EDSS) and presence or absence of previous optic neuritis episodes. METHODS: We recruited 62 patients with multiple sclerosis (53 relapsing-remitting and 9 secondary progressive) and 12 disease-free controls. All patients underwent an ophthalmological examination, including quantitative analysis of the nerve fibre layer and macular thickness using optical coherence tomography. Patients were classified according to EDSS as A (lower than 1.5), B (between 1.5 and 3.5), and C (above 3.5). RESULTS: Mean nerve fibre layer thickness in control, A, B, and C groups was 103.35±12.62, 99.04±14.35, 93.59±15.41, and 87.36±18.75µm respectively, with statistically significant differences (P<.05). In patients with no history of optic neuritis, history of episodes in the last 3 to 6 months, or history longer than 6 months, mean nerve fibre layer thickness was 99.25±13.71, 93.92±13.30 and 80.07±15.91µm respectively; differences were significant (P<.05). Mean macular thickness in control, A, B, and C groups was 220.01±12.07, 217.78±20.02, 217.68±20.77, and 219.04±24.26µm respectively. Differences were not statistically significant. CONCLUSIONS: The mean retinal nerve fibre layer thickness in multiple sclerosis patients is related to the EDSS level. Patients with previous optic neuritis episodes have a thinner retinal nerve fibre layer than patients with no history of these episodes. Mean macular thickness is not correlated to EDSS level.

Hypersensitivity reactions to fluoroquinolones: analysis of the factors involved.

BACKGROUND: Hypersensitivity reactions to fluoroquinolones seem to be on the increase, especially immediate type reactions. OBJECTIVE: The aim of this study was to determine whether several conditions, including gender, age, type of reaction, time interval between the reaction and the study, type of symptoms, the specific fluoroquinolone involved in the reaction and previous confirmed hypersensitivity to betalactams or to other drugs were factors contributing to the development of hypersensitivity to fluoroquinolones. METHOD: We analysed retrospectively all patients attending our allergy department between January 2005 and December 2010 because of a reaction associated with fluoroquinolone administration. The diagnosis was confirmed by basophil activation test or drug provocation tests. In accordance with the results, patients were then classified as having hypersensitivity or non-hypersensitivity to fluoroquinolones. RESULTS: A group of 218 patients was evaluated; 69 were confirmed as having hypersensitivity, 146 as non-hypersensitivity and 3 were excluded. Comparisons between groups showed that the allergic patients more often had a previous confirmed hypersensitivity to betalactams (P = 0.029), immediate reactions (P = 0.001) and anaphylaxis (P = 0.000), and moxifloxacin was the fluoroquinolone most frequently involved (P = 0.027). The logistic regression analysis showed three factors associated with the diagnosis of hypersensitivity reactions to fluoroquinolones: previous hypersensitivity to betalactams (OR: 4.571; 95% CI: 0.987-21.171; adjusted OR: 23.654; 95% CI: 1.529-365.853), immediate reactions (OR: 17.333; 95% CI: 4.374-68.691; adjusted OR: 52.493; 95% CI: 6.621-416.200) and reactions induced by moxifloxacin (OR: 3.091; 95% CI: 1.160-8.239; adjusted OR: 13.610; 95% CI: 2.419-76.565). CONCLUSION: In patients who develop reactions to fluoroquinolones, hypersensitivity is more often confirmed in those with immediate reactions and when moxifloxacin is involved. Moreover, patients with hypersensitivity to betalactams are more prone to develop hypersensitivity reactions to fluoroquinolones.

Drug hypersensitivity reactions: response patterns, drug involved, and temporal variations in a large series of patients.

BACKGROUND: Drug hypersensitivity reactions (DHRs) are among the most frequent reasons for consultation in allergy departments, and are becoming more common due to increasing prevalence and case complexity. OBJECTIVE: To study the clinical characteristics, drugs involved, diagnostic methods, and temporal variation of DHRs in a large series of patients over a 6-year period. METHODS: We included all patients attending our department between 2005 and 2010. The diagnosis was performed by in vivo and/or in vitro tests (basophil activation test and specific immunoglobulin [Ig] E in serum and drug provocation testing [DPT]) when indicated. RESULTS: We evaluated 4460 patients who reported 4994 episodes (mean [SD] of 1.13 [0.36] [range, 1-3] episodes per patient). Based on clinical history, 37% of the episodes were attributed to nonsteroidal anti-inflammatory drugs (NSAIDs), 29.4% to beta-lactam antibiotics (BLs), 15% to non-BLs, and 18.4% to other drugs.Analysis of the 1683 patients (37.45%) finally confirmed as allergic showed the most frequent diagnosis to be hypersensitivity to multiple NSAIDs (47.29%), followed by immediate reactions to BLs (18.12%). There was an increase in reactions to non-BLs (from 21.2% to 31.9%; P < .03) over the study period, mainly due to an increase in allergy to quinolones (from 0.5% to 6.8%; P < .02); 44% of patients were diagnosed by clinical history, 14.6% by skin tests, 10.4% by in vitro tests, and 30.8% by DPT. CONCLUSIONS: NSAIDs were the drugs most frequently involved in DHRs and the most common diagnosis was urticaria/angioedema with cross intolerance. Reactions to emerging drugs such as quinolone derivatives and radiocontrast media are becoming more common.

Factors associated with serous retinal detachment in highly myopic eyes with inferior posterior staphyloma. / Factores asociados con el desprendimiento neurosensorial macular en pacientes miopes magnos con estafiloma inferior.

PURPOSE: To investigate the factors associated with persistent serous retinal detachment in highly myopic eyes with inferior posterior staphyloma. METHODS: A total of 27 highly myopic patients (44 eyes) with an inferior posterior staphyloma were recruited. Serous retinal detachment was investigated; 13 eyes had persistent sub-macular fluid (study group), and 31 eyes lacked sub-macular fluid (control group). All patients underwent complete ophthalmologic examinations, including axial length measurement and fluorescein angiography (FA). Triton Deep Range Imaging (DRI) optical coherence tomography (OCT) (Topcon Corp., Tokyo, Japan) scans through the fovea measured choroidal thicknesses, macular bend height, and vitreoretinal interface factors. RESULTS: Of the 44 eyes, 13 had neurosensory retinal detachment and 31 did not. No significant differences were found in any of the studied variables (age, gender, spherical equivalence, axial length, vitreomacular traction, epiretinal membrane, internal limiting membrane detachment), except a higher macular bend height (p = 0.01), and a reduced macular choroidal thickness (p = 0.02), which were associated with the risk of serous retinal detachment. No statistically significant differences in best-corrected visual acuity (BCVA) were observed between the study and control groups. Serous retinal detachment always occurred at the bisected retinal pigment epithelium of the macula corresponding to the upper edge of the staphyloma, and was characterised by multiple hyperfluorescent granular patches on fluorescein angiography. CONCLUSIONS: A higher macular bend height and a reduced macular choroidal thickness may be important factors in the development of serous retinal detachment in patients with inferior posterior staphyloma.

Prospective analysis of macular and optic disc changes after non-arteritic anterior ischemic optic neuropathy.

PURPOSE: To prospectively analyse macular and optic disc changes after the occurrence of non-arteritic anterior ischemic optic neuropathy (NAION) and study possible predictors of final visual outcome. METHODS: Patients with NAION underwent a complete ophthalmic examination, including spectral-domain optical coherence tomography of the macula and optic nerve head. The examination was repeated 1, 3, 6, 9 and 12 months after onset. Final visual prognosis was evaluated by visual field (VF) and best-corrected visual acuity (BCVA) at the final visit. Data within the NAION group were analysed over the course of the disease and compared to a disease-free control group at each visit. RESULTS: Twenty-two eyes with NAION and 43 eyes from a control group were included. The retinal nerve fiber layer (RNFL) was significantly thicker in NAION eyes than controls at presentation (P=0.00), and significantly decreased during the next 3 months after presentation (P=0.02). The ganglion cell+inner plexiform layer (GCIPL) was thinner in the NAION group throughout the course of the disease (all P<0.05). Although the acute NAION eyes had significantly lower cup/disc ratios and higher neuroretinal and disc sizes (all P=0.00), there were no significant differences between groups from the third month onwards (all P>0.05). The best predictors of BCVA and VF were GCIPL at 3 months of follow-up (r2=0.32; P=0.03) and RNFL at 6 months of follow-up (r2=0.41; P=0.01) respectively. CONCLUSIONS: RNFL and optic disc changes occur during the first 3 months after the onset of NAION, whereas GCIPL is affected soon after the onset of symptoms. GCIPL and RNFL are useful predictors of final visual outcome.

[Relationship between central corneal thickness, intraocular pressure and severity of glaucomatous visual field loss]. / Correlación entre grosor corneal central, presión intraocular y afectación glaucomatosa del campo visual.

OBJECTIVE: to determine central corneal thickness in normal subjects, glaucomatous patients and ocular hypertension patients, to evaluate if the central corneal thickness is related to the presence of glaucoma or ocular hypertension. Furthermore, we aim to verify the relationship between central corneal thickness and severity of glaucomatous visual field loss. METHODS: comparative study including 150 eyes of 150 subjects, separated into three groups: normal (47 eyes), ocular hypertension (35) and glaucomatous (68). This last group was subdividided in three subgroups depending on the Hodapp-Parrish-Anderson criteria for scoring Humphrey visual field defects (initial, moderate and advanced). We evaluated the visual field, the central corneal thickness measured by pachymetry and the intraocular pressure measured by Goldmann tonometry. Results were analysed using the Student's t-test for normally distributed independent samples. RESULTS: the central corneal thickness was 526+/-25 microns (mean +/-standard deviation (SD)) in glaucomatous patients, 560+/-27 microns in ocular hypertension patients, and 556+/-27 microns in the normal group. Statistical significance could be found between the glaucomatous group of patients and the other groups (p< 0.01), but not between the ocular hypertension group and normal subjects (p= 0.4). The comparison between central corneal thickness of the subgroup with advanced damage of the visual field and the two other subgroups was also statistically significant (p< 0.01), but not between the subgroups of initial damage and moderate damage (p= 0.7). CONCLUSIONS: the central corneal thickness in glaucomatous patients is lower than in normal subjects and in ocular hypertension patients. Patients classified as having advanced damage in their visual field have significantly lower central corneal thickness measurements than patients classified as having initial or moderate damage.

Longitudinal study of visual function in patients with relapsing-remitting multiple sclerosis with and without a history of optic neuritis. / Estudio longitudinal de la función visual en pacientes con esclerosis múltiple remitente-recurrente con y sin antecedentes de neuritis óptica.

INTRODUCTION: The contrast sensitivity test determines the quality of visual function in patients with multiple sclerosis (MS). The purpose of this study is to analyse changes in visual function in patients with relapsing-remitting MS with and without a history of optic neuritis (ON). METHODS: We conducted a longitudinal study including 61 patients classified into 3 groups as follows: a) disease-free patients (control group); b) patients with MS and no history of ON; and c) patients with MS and a history of unilateral ON. All patients underwent baseline and 6-year follow-up ophthalmologic examinations, which included visual acuity and monocular and binocular Pelli-Robson contrast sensitivity tests. RESULTS: Monocular contrast sensitivity was significantly lower in MS patients with and without a history of ON than in controls both at baseline (P=.00 and P=.01, respectively) and at 6 years (P=.01 and P=.02). Patients with MS and no history of ON remained stable throughout follow-up whereas those with a history of ON displayed a significant loss of contrast sensitivity (P=.01). Visual acuity and binocular contrast sensitivity at baseline and at 6 years was significantly lower in the group of patients with a history of ON than in the control group (P=.003 and P=.002 vs P=.006 and P=.005) and the group with no history of ON (P=.04 and P=.038 vs P=.008 and P=.01). However, no significant differences were found in follow-up results (P=.1 and P=.5). CONCLUSIONS: Monocular Pelli-Robson contrast sensitivity test may be used to detect changes in visual function in patients with ON.

[Analysis of the quantitative differences in the thickness of the retinal nerve fibre layer between time-domain and spectral-domain optical coherence tomography in patients with relapsing-remitting multiple sclerosis]. / Analisis de las diferencias cuantitativas en el grosor de la capa de fibras nerviosas retiniana entre la tomografia de coherencia optica de dominio-tiempo y de dominio-espectral en pacientes con esclerosis multiple remitente recurrente.

INTRODUCTION: Optical coherence tomography (OCT) is a tool that is increasingly more commonly used in the study of neuro-degenerative diseases. AIMS: To analyse and correlate the thickness of the retinal nerve fibre layer (RNFL) by means of time-domain and spectral-domain OCT in patients with relapsing-remitting multiple sclerosis (MS), with and without a history of optic neuritis (ON). SUBJECTS AND METHODS: We conducted a cross-sectional study of the thickness (mean and by quadrants) of the RNFL of 15 disease-free subjects, 28 with MS with no prior history of ON and 18 with a history of ON. The full ophthalmologic examination included measurement of the RNFL by means of time-domain and spectral-domain tomography. RESULTS: Statistically significant differences are found between the two tomography scans on comparing the mean thickness of the RNFL of the control group (p = 0.000), the group with a history of ON (p = 0.000) and the group without ON (p = 0.000). We obtained a strong, statistically significant and directly proportional correlation between the mean thickness of the RNFL measured with the two types of tomography in the control group (rho = 0.842; p = 0.000), and the groups of eyes without ON (rho = 0.91; p = 0.000) and with ON (rho = 0.902; p = 0.000). CONCLUSIONS: There is a strong correlation between the two tomography scans in the measurement of the thickness of the RNFL in patients with MS, with and without a history of ON. Time-domain OCT quantifies greater thicknesses, and therefore both types of tomography have proven to be effective in the study of MS, although the results cannot be interchanged or extrapolated.

TITLE: Analisis de las diferencias cuantitativas en el grosor de la capa de fibras nerviosas retiniana entre la tomografia de coherencia optica de dominio-tiempo y de dominio-espectral en pacientes con esclerosis multiple remitente recurrente.Introduccion. La tomografia de coherencia optica (OCT) es una herramienta cada vez mas extendida en el estudio de las enfermedades neurodegenerativas. Objetivos. Analizar y correlacionar el grosor de la capa de fibras nerviosas retiniana (CFNR) mediante OCT de dominio-tiempo y dominio-espectral en pacientes con esclerosis multiple (EM) remitente recurrente, con y sin antecedente de neuritis optica (NO). Sujetos y metodos. Estudio transversal del grosor medio y por cuadrantes de la CFNR en 15 sujetos libres de enfermedad, 28 con EM sin historia previa de NO y 18 con antecedentes de NO. La exploracion oftalmologica completa incluia la medicion de la CFNR mediante tomografos de dominio-tiempo y dominio-espectral. Resultados. Existen diferencias estadisticamente significativas entre ambos tomografos al comparar el grosor medio de la CFNR en el grupo control (p = 0,000), el grupo con antecedentes de NO (p = 0,000) y el grupo sin NO (p = 0,000). Hemos obtenido una fuerte correlacion, estadisticamente significativa y directamente proporcional entre el grosor medio de la CFNR medido con ambos tomografos en el grupo control (rho = 0,842; p = 0,000), y los grupos de ojos sin NO (rho = 0,91; p = 0,000) y con NO (rho = 0,902; p = 0,000). Conclusiones. Existe una fuerte correlacion en la medicion del grosor de la CFNR entre ambos tomografos en pacientes con EM, con y sin antecedente de NO. La OCT de dominio-tiempo cuantifica grosores mayores, por lo que ambos tomografos se demuestran eficaces en el estudio de la EM, aunque los resultados no son intercambiables ni extrapolables.

Molluscum contagiosum in a patient with no risk factors.

PURPOSE: To report a case of molluscum contagiosum in a patient with no risk factors. METHODS: A 38-year-old patient with a tumor located in the lower eyelid that appeared 5 months previously was seen in the authors' hospital. The lesion had grown slowly and appeared as a crateriform mass with elevated edges. It was surgically excised and the histopathology study confirmed the diagnosis of molluscum contagiosum. Risk factors were absent. RESULTS: The histopathologic study confirms the presence of eosinophilic inclusion bodies in the keratinocytes cytoplasm. CONCLUSIONS: External evaluation of the lower lid lesion did not show the morphologic configuration of a molluscum contagiosum. A virus can be suspected if attention is paid to the margin of the eyelid and the patient's age.

Dexamethasone intravitreal implant for treatment of persistent macular oedema in Birdshot retinochoroidopathy.

CLINICAL CASE: The case is reported of a 32 year-old man with a bilateral cystoid macular oedema and serous macular detachment due to birdshot retinochoroidopathy. An intravitreal implant of 0.7 mg dexamethasone (Ozurdex®, Allergan) was performed on both eyes, after a partial response of the macular oedema to oral and subtenon corticosteroids. Anatomical and visual improvements were observed and maintained after six months of follow up. DISCUSSION: Intravitreal dexamethasone implant may be a good therapeutic option in patients with macular oedema due to Birdshot retinochoroidopathy, and who were refractory or had intolerance to previous therapies.

Macular choroidal thickness in non-arteritic ischemic optic neuropathy. / Grosor coroideo macular en la neuropatía óptica isquémica anterior no arterítica.

OBJECTIVE: To analyse macular choroidal thickness (MCT) in non-arteritic ischaemic optic neuropathy (NAION). MATERIALS AND METHODS: An analysis was made on 22 patients diagnosed with NAION (22 eyes) and 42 healthy controls (42 eyes) using enhanced-depth imaging of spectral-domain optical coherence tomography. A horizontal raster scan centred on the fovea was obtained per eye 3 months after the onset of NAION. Three measurements of MCT were obtained from the posterior edge of the retinal pigment epithelium to the choroid-sclera junction at 500µm intervals. Statistical analysis was used to compare the mean MCT and to correlate MCT with other ocular and systemic parameters. RESULTS: Except for refractive error (P=.01), there were no statistically significant differences between both groups in axial length (P=.53), age (P=.88) and other epidemiological and ocular parameters. Mean MCT in NAION eyes and control group was 236.21±63.29µm and 269.13±52.28, respectively. Mean MCT was significantly thinner in NAION eyes than in healthy eyes (P=.03). Thinner MCT, adjusted for refractive error, was associated with the diagnosis of NAION (P=.04). CONCLUSIONS: Eyes affected by NAION showed significantly thinner MCT compared with healthy control eyes after adjusting for refractive error.

Effects of a non-selective beta-blocker on adult rat anterograde axonal transport and retinal ganglion layer after increased intraocular pressure.

The aim of this study was to examine the effects of timolol in an experimental model of elevated intraocular pressure (IOP). Three episcleral veins of rats with normal IOP were cauterized. Three months later we examined the effects on anterograde axonal transport from the retinal ganglion cells (RGCs) to the superior colliculus (SC) as well as on the number of neurons in the retinal ganglion layer (RGL). These parameters were also studied in a group of rats submitted to treatment with timolol after confirming that their IOP was still raised after two weeks. After the surgical procedure, the mean IOP of the experimental eyes increased to 33.5+/-1.06 mmHg (1.25 fold compared to the control group) and three months later the IOP remained significantly elevated; however, after a long period of treatment with timolol the IOP was 14.05+/-0.81 mmHg, similar to that of the control group. In the group with normal IOP, labelling with horseradish rabbit peroxidase (HRP) at 120 minutes and 24 hours postinjection showed continuous staining from the retina to the SC. In the experimental group the optic nerve head (ONH) was completely negative, although in the group treated with timolol there was partial block of axonal transport in the ONH, in which the staining was slightly more intense. The number of neurons in the RGL, counted by immunohistochemical labelling with Neu-N, showed that in eyes with normal and elevated IOP there were 423+/-11 neurons/mm(2) and 283+/-10 neurons/mm(2), respectively. After treatment with timolol the number of neurons (331+/-10 cells/mm(2) increased compared with elevated IOP eyes, although the number did not reach that of the control group. These results indicate that treatment with timolol, started two weeks after the surgical procedure, was partially neuroprotective because the loss of neurons in the RGL was lower than in untreated animals, though not sufficient to re-establish normal axonal transport.

[In vitro activity of furazolidone and nitrofurantoin in Helicobacter pylori clinical isolates and study of mutation rate]. / Actividad in vitro de la furazolidona y la nitrofurantoína en aislamientos clínicos de Helicobacter pylori y estudio de la tasa de mutación.

Clarithromycin, amoxicillin, tetracycline and metronidazole are the most frequently used antimicrobials for Helicobacter pylori infection treatment. While tetracycline and amoxicillin resistance are rare, clarithromycin and metronidazole resistance vary in different populations and are considered factors for treatment failure. The aim of this study was to determine the in vitro activity of furazolidone and nitrofurantoin in 164 H. pylori clinical isolates by agar dilution and to determine the spontaneous mutation rate. Metronidazole and clarithromycin resistance were 23.77% (CI95%: 18.96-29.14) and 16.78% (CI95%: 12.64-21.62), respectively; moreover, 1.4% (CI95%: 0.38-3.54) were intermediate to clarithromycin. All the isolates were susceptible to amoxicillin and tetracycline. Furazolidone and nitrofurantoin resistance rates were 1.82% (CI95%: 0.37-5.25) and 0.6% (CI95%: 0-3.35), respectively. The three furazolidone-resistant strains were nitrofurantoine-susceptible (MIC 4 mg/l for furazolidone and 2 mg/l for nitrofurantoin) and the nitrofurantoin-resistant strains were furazolidone-susceptible (MIC 4 mg/l for nitrofurantoin and 1 mg/l for furazolidone). These four strains were metronidazole-resistant (MIC 16 mg/l). Furazolidone or nitrofurantoin spontaneous mutants were not detected in the eight H. pylori strains tested. However, mutants with resistance to metronidazole were found with all the strains with a mutation rate of 7.4 x 10(-10) to 9.4 x 10(-10). Furazolidone and nitrofurantoin showed an excellent in vitro activity against the H. pylori clinical isolates included herein, supporting the usefulness of furazolidone as second-line antimicrobial after treatment failure or as first-line therapy in populations with low economical resources.

[Use of optical coherence tomography to study variations of normal parameters with age]. / Estudio de parámetros de normalidad en relación a la edad con el tomógrafo óptico de coherencia.

PURPOSE: To determine by Optical Coherence Tomography (OCT) the variation of a variety of measurable parameters (macular thickness, retinal parapapillary fiber layer thickness and optic disc morphology) with age. METHOD: We carried out OCT in 40 normal subjects (80 eyes) aged between 20 and 60 years, divided into 4 groups according to the age decades. RESULTS: Statistically significant differences were found in the macular thickness in the comparative study groups but the differences varied according to the sector assessed; the superior outer sector (p=0.00), temporal outer sector (p=0.01), temporal inner sector (p=0.04), nasal inner sector (p=0.03) and inferior inner sector (p=0.00). In the study of retinal parapapillary fiber layer thickness, statistically significant differences were found between groups in the inferior sector only (p=0.04). No statistically significant differences were found between groups in the study of optic disc morphology. CONCLUSIONS: Both the macular thickness and the nerve fiber layer in the inferior sector decrease with age. These differences in thickness are statistically significant between the extremes of age decades.

Relationship between paravascular abnormalities and foveoschisis in highly myopic patients.

PURPOSE: To describe the prevalence of paravascular abnormalities in highly myopic patients and its relationship with myopic foveoschisis (MF). METHODS: Cross-sectional study of 250 highly myopic eyes. All of the patients underwent a complete ophthalmologic examination that included optical coherence tomography . RESULTS: Optical coherence tomography images showed 170 eyes (68%) with paravascular microfolds (PM), 121 eyes (48.4%) presented paravascular retinal cysts (PC), and 35 eyes (14%) with paravascular lamellar holes . All the eyes with PCs had PMs. Out of the 250 eyes, 48 (19.2%) had paravascular retinoschisis (PR). All the eyes (100%) with PR had paravascular cysts and PMs. Sixteen eyes (6.4%) had foveoschis. The spherical equivalent (P<0.00), PR (P=0.01), and the presence of tractional structures (P<0.00) were associated with increased risk for foveoschsis in the multivariate study. CONCLUSIONS: PMs were the lesions most often observed in the paravascular area in highly myopic eyes. MF would be a result of the action of different forces (intra- and extra-ocular forces), specially tractional structures, on precursor lesions (paravascular cyst and paravascular restinoschisis). Further studies are needed to confirm these results.

Effect of WEB 2086-BS, an antagonist of platelet-activating factor receptors, on retinal vascularity in diabetic rats.

Specific antagonists of platelet-activating factor (PAF) receptors inhibit platelet aggregation and thromboxane synthesis. These two processes have been implicated in the course of diabetic retinopathy. We assessed the effect of a specific PAF receptor antagonist, WEB 2086-BS (3-(4-(2-chlorophenyl)-9-methyl-6H-thieno(3,2-f) (1,2,4 triazolo-(4,3-a(1,4)-diazepine-2-yl)-1-(4-morpholinyl)-1-propanone) on retinal vascularity in a model of experimental streptozocin-induced diabetes in rats. Rats were divided into five experimental groups (10 animals/group): group I, non-diabetic group II, untreated diabetic group III, diabetic given 1 mg/kg per day of WEB 2086-BS (p.o.) group IV, diabetic given 5 mg/kg per day (p.o.) and group V, diabetic given 10 mg/kg per day (p.o.). After 3-month treatment, platelet aggregometry, platelet synthesis of thromboxane B2, aortic production of 6-keto-prostaglandin F1alpha, platelet and vascular lipid peroxidation, and percentage of the retinal area occupied by horseradish peroxidase-labeled vessels were measured. Untreated diabetic rats showed an increase in platelet reactivity, reduced 6-keto-prostaglandin F1alpha production, increased thromboxane B2 and lipid peroxides, and a decrease in the percentage of retinal area occupied by horseradish peroxidase-labeled vessels. WEB 2086-BS produced a decrease in platelet aggregation induced by collagen in whole blood, in thromboxane B2 synthesis and lipid peroxide production, and an increase in the percentage of retinal area occupied by horseradish peroxidase-labeled vessels (13.9+/-1.1% in group II and 9.9+/-0.8% in group V). There was a statistically significant linear correlation (Y= -0.72 + 137X, r2 = 0.7247, P < 0.0007) between thromboxane B2 values and the percentages of retinal area occupied by horseradish peroxidase-labeled vessels in the groups of animals treated with WEB 2086-BS.

Effect of camonagrel, a selective thromboxane synthase inhibitor, on retinal vascularization in experimental diabetes.

Platelet hyperactivity accompanied by an increased synthesis of thromboxane and/or a decreased prostacyclin production are important factors in ischemic diabetic retinopathy. We studied the effect of camonagrel and dazoxiben, two thromboxane synthase inhibitors, on retinal vascularization in a model of streptozotocin-induced diabetes in rats. Ten nondiabetic rats, 10 diabetic animals treated with saline (i.e., not treated), and 60 diabetic animals treated with dazoxiben or camonagrel (10, 50 or 100 mg kg(-1) day(-1) p.o.) were studied. All treatments lasted for 90 days. Dazoxiben and camonagrel produced a dose-dependent reduction in platelet aggregation and thromboxane synthesis. Dazoxiben increased prostacylin synthesis by 78% at 100 mg kg(-1) day(-1), and camonagrel by 154%. Dazoxiben increased retinal vascularity by 74%, and by 183% after camonagrel treatment. Prostacyclin synthesis showed a direct linear correlation with the degree of retinal vascularization (r2=0.6733, P < 0.00001). We conclude that an increased prostacyclin synthesis may have a greater influence than the inhibition of thromboxane synthesis in preventing ischemic diabetic retinopathy in experimental diabetes. Camonagrel may be an alternative treatment in the prevention of these lesions.

The pyrimido-pyrimidine derivatives, dipyridamole, mopidamol and RA-642, prevent from retinal vascular defects in experimental diabetes mellitus.

We compared the effects of dipyridamole, RA-642, and mopidamol on platelet activity and thromboxane/prostacyclin balance in relation to the degree of retinal vascularization in a model of experimental streptozotocin-induced diabetes in rats. After 3 months, collagen-induced platelet aggregation in whole blood was 25% higher in diabetic animals than in nondiabetics. Dipyridamole inhibited 43% platelet aggregation, mopidamol 39%, and RA-642 36%. Platelet production of thromboxane B2 was 87% higher in untreated diabetic rats. Mopidamol and RA-642 produced a 46% and 41% inhibition of thromboxane B2. Dipyridamole did not inhibited thromboxane B2 synthesis. Aortic production of 6-keto-PGF1 alpha was 43% lower in untreated diabetic animals and showed no change after treatment with either mopidamol or RA-642. In contrast, dipyridamole caused a 90% increase in aortic production of prostacyclin. Computerized analysis of retinal vascularization showed that untreated diabetic rats had a 81% decrease in the area occupied by peroxidase-labelled vessels as compared with nondiabetics. Treatment with dipyridamole, mopidamol, and RA-642 caused 2.5-fold, 2.8-fold and four-fold increases, respectively, in the percentage of retinal surface occupied by peroxidase-labelled vessels. Differences in retinal vascularization between diabetic animals given RA-642 and nondiabetic controls were negligible.

[Susceptibility of Campylobacter jejuni clinical isolates from children to eight antibiotics]. / Sensibilidad de Campylobacter jejuni a ocho antibióticos en cepas aisladas de muestras clínicas de niños.

This study aimed to identify the activity of eight antibiotics (ofloxacin, moxifloxacin, azithromycin, erythromycin, clindamycin, ampicillin, amoxicillin-clavulanic acid and tetracycline) against 80 strains of Campylobacter jejuni isolated from children. Minimal inhibitory concentrations (MIC) were determined by an agar dilution method. Resistance to azithromycin and erythromycin was considered when MIC > or =8 mg/l, to clindamycin when MIC > or =1 mg/l, to amoxicillin-clavulanic acid and ampicillin when MIC > or =32 mg/l, to ofloxacin and moxifloxacin when MIC > or =4 mg/l, and to tetracycline when MIC > or =16 mg/l. All strains tested were susceptible to amoxicillin-clavulanic acid. The lowest frequency of resistance was to azithromycin (2%), erythromycin (3.7%), clindamycin (4.4%) and ampicillin (4.9%), and the highest was to ofloxacin and tetracycline (61.7% for both), and moxifloxacin (37%). Considered the antibiotics of choice for the treatment of infections caused by this microorganism, macrolides showed excellent activity with MIC(90)=0.5 mg/l for azithromycin and MIC(90)=0.5 mg/l for erythromycin.

Impression cytology of the conjunctival epithelium after antiglaucomatous treatment with latanoprost.

PURPOSE: To study nongoblet and goblet epithelial conjunctival cells after several treatment periods with latanoprost, a prostaglandin analogue. METHODS: Twelve patients (20 eyes) were studied before the onset of treatment and after 1, 3, and 6 months of latanoprost use. Impression cytology was carried out to analyze cellular density and morphologic parameters such as minimum and maximum diameter and area. RESULTS: Nongoblet epithelium cell density did not change over the treatment period. The density of goblet cells increased after 1 month of use, but returned to initial cell density after longer treatment periods. Nongoblet epithelial cells underwent a significant reduction in size after 1, 3, and 6 months of treatment. In addition, the minimum/maximum diameter ratio suggested that after 1 month there were some changes in shape (a slight elongation) when compared to cells of untreated patients. Nevertheless, after longer treatment periods, the cells regained their original shape. No changes in size were observed in goblet cells, except for a slight decrease in maximum diameter after 6 months of treatment, which suggests that the cells became more rounded. CONCLUSIONS: The density of nongoblet epithelial cells does not change after different treatment periods with latanoprost. However, their size decreases and after short treatment periods their shape also undergoes changes. The density of goblet cells increases after 1 month of treatment, but decreases again after longer periods. Their size does not undergo any modification, although there is a variation in shape after 6 months of treatment.