Stenotrophomonas maltophilia keratitis treated with trimethoprim-sulfamethoxazole.

CASE REPORT: An 84 year-old woman with persistent epithelial defect and a dense stromal infiltrate post-corneal transplantation. According to the microbiological results, it was due to a Stenotrophomonas maltophilia (S. maltophilia) resistant to all antibiotics except trimethoprim-sulfamethoxazole (TMP/SMX). Healing was achieved after three weeks of treatment with oral and topical TMP/SMX. DISCUSSION: S. maltophilia is an opportunistic microorganism rarely described in ophthalmology. It is associated with conjunctivitis, keratitis, scleritis, dacryrocystitis, cellulitis, and endophthalmitis with significant morbidity. Treatment is complicated because of its resistances to broad-spectrum antibiotics. TMP/SMX monotherapy can be considered an option of treatment for this type of keratitis.

[Effect on ocular blood flow of Combigan® versus placebo in patients with ocular hypertension]. / Efecto de Combigan(®) versus placebo en el flujo sanguíneo ocular en pacientes hipertensos oculares.

PURPOSE: This study was undertaken to compare the ocular haemodynamic effects of Combigan(®) versus placebo in patients with ocular hypertension (OHT). METHODS: Thirty patients with OHT were included in a controlled, randomised, double blind study in two parallel groups; 15 were randomised to receive Combigan(®) and 15 to receive placebo for a period of 3 months. At baseline and at 3 months retrobulbar blood flowmeasurements of the ophthalmic artery (OA) and central retinal artery (CRA) were taken using colour Doppler imaging(CDI) ultrasound, concurrently with intraocular pressure (IOP). RESULTS: Combigan(®) significantly reduced IOP after 3 months of treatment (P = 0.001), whereas placebo showed no significant change in IOP. The baseline haemodynamic parameters were similar between treatment and placebo groups. Patients treated with Combigan® showed a statistically significant decrease in CRA resistive index (P = 0.007). CONCLUSIONS: Patients treated for 3 months with Combigan(®) showed a significant decrease of CRA resistive index that could be explained by the decrease in IOP.

Efecto de Combigan® versus placebo en el flujo sanguíneo ocular en pacientes hipertensos oculares / Effect on ocular blood flow of Combigan® versus placebo in patients with ocular hypertension

Propósito: Estudiar los cambios hemodinámicos retrobulbares mediante ecografía dopplercolor, en pacientes hipertensos oculares (HTO) en tratamiento con Combigan® versus placebo.Método: Treinta pacientes randomizados en 2 grupos paralelos fueron incluidos en un estudioprospectivo y a doble ciego; quince de ellos en tratamiento con Combigan® y quince entratamiento con placebo, durante un periodo de 3 meses. Se obtuvieron medidas de la presiónintraocular (PIO) y del flujo sanguíneo a nivel de la arteria central de la retina (ACR) y la arteriaoftámica en el momento basal y a los 3 meses.Resultados: Combigan® redujo significativamente la PIO tras tres meses de tratamiento(p = 0,001). Los parámetros hemodinámicos basales fueron similares entre los grupos placeboy tratamiento. Los pacientes tratados con Combigan® mostraron un descenso estadísticamentesignificativo del índice de resistencia de la ACR (p = 0,007).Conclusiones: Los pacientes tratados durante 3. meses con Combigan® mostraron un descensoestadísticamente significativo del índice de resistenciade la ACR que podría explicarsepor el descenso de PIO(AU)

Purpose: This study was undertaken to compare the ocular haemodynamic effects ofCombigan® versus placebo in patients with ocular hypertension (OHT).Methods: Thirty patients with OHT were included in a controlled, randomised, double blindstudy in two parallel groups; 15 were randomised to receive Combigan® and 15 to receiveplacebo for a period of 3 months. At baseline and at 3 months retrobulbar blood flowmeasurementsof the ophthalmic artery (OA) and central retinal artery (CRA) were taken usingcolour Doppler imaging(CDI) ultrasound, concurrently with intraocular pressure (IOP). Results: Combigan® significantly reduced IOP after 3 months of treatment (P = 0.001), whereasplacebo showed no significant change in IOP. The baseline haemodynamic parameters weresimilar between treatment and placebo groups. Patients treated with Combigan® showed astatistically significant decrease in CRA resistive index (P = 0.007).Conclusions: Patients treated for 3 months with Combigan® showed a significant decrease ofCRA resistive index that could be explained by the decrease in IOP(AU)

La vitrectomía como terapia antinflamatoria de la uveítis intermedia en niños / Pars plana vitrectomy as anti-inflammatory therapy for intermediate uveitis in children

ObjetivoLas uveítis intermedias constituyen entre el 2 y el 26% de las uveítis en niños. El curso natural es variable existiendo desde casos leves autolimitados hasta formas crónicas más severas que cursan con múltiples recurrencias y complicaciones. El objetivo de este estudio es valorar la utilidad de la vitrectomía para controlar la inflamación en niños con uveítis intermedias recurrentes.MétodosEstudio retrospectivo con seguimiento de al menos seis meses. Se incluyeron todos los niños menores de dieciséis años intervenidos mediante vitrectomía por uveítis intermedia tras haber sufrido al menos dos brotes de inflamación intermedia sin tratamiento profiláctico inmunosupresor sistémico previo a la cirugía. Se recogieron los cambios en la agudeza visual (AV), las recaídas y las complicaciones derivadas de la cirugía.ResultadosSe seleccionaron siete ojos de cinco niños con uveítis intermedia que requirieron vitrectomía. Tras un seguimiento medio de 34 meses, la AV había mejorado en todos los ojos respecto a la situación prequirúrgica. Cuatro ojos desarrollaron cataratas subcapsulares posteriores leves. Las recurrencias posquirúrgicas fueron de localización anterior y controladas con tratamiento tópico, salvo un brote de uveítis intermedia tratada con una inyección de triamcinolona periocular. Solo un niño se encuentra actualmente bajo terapia inmunosupresora sistémica, debido a la presencia de brotes de uveítis intermedia en el ojo no operado y dado que sus padres rechazaron la cirugía.ConclusiónLa vitrectomía con crioterapia inferior es una opción terapéutica a considerar para el control de la actividad inflamatoria de las uveítis intermedias en niños a medio plazo para evitar los efectos secundarios asociados a los inmunosupresores sistémicos(AU)

PurposeIntermediate uveitis represents between 2 and 26% of uveitis in children. The spectrum of the disease is highly variable, ranging between mild cases that resolve spontaneously and chronic, severe forms that develop multiple episodes and complications. The purpose of this study is to evaluate the efficacy of vitrectomy to control inflammation in children with recurrent intermediate uveitis.MethodsRetrospective evaluation of patients with at least six months of follow-up. All patients under 16 who had undergone vitrectomy for intermediate uveitis were included. Vitrectomy was performed after at least two episodes of intermediate uveitis in children that had had no previous prophylactic systemic immunosuppressant treatment. Data recorded were visual acuity (VA), recurrences and surgical complications.ResultsSeven eyes of five children with intermediate uveitis who underwent vitrectomy were included. After a mean follow-up of 34 months, VA improved in all eyes after surgery. Four eyes developed mild subcapsular posterior cataracts. Post-surgical recurrences were anterior and responded to topical treatment, except for an episode of intermediate uveitis that required a periocular injection of triamcinolone. Only one patient is being treated with systemic immunosuppressants, due to the presence of repeated episodes of uveitis in the non-vitrectomised eye and since his parents were unwilling to have him undergo new surgery.ConclusionsVitrectomy with inferior cryotheraphy controls inflammation in intermediate uveitis in children with good mid-term results avoiding the secondary side-effects of systemic immunosuppressants(AU)

[Evaluation of the effect of bimatoprost/timolol fixed combination on ocular blood flow in patients with ocular hypertension using colour Doppler imaging. Preliminary study]. / Evaluación mediante ecografía doppler color del efecto de la combinación fija bimatoprost/timolol sobre el flujo sanguíneo ocular en pacientes con hipertensión ocular. Estudio preliminar.

PURPOSE: To investigate the effects of topical bimatoprost (0.3 mg/ml)/timolol maleate (5 mg/ ml) fixed combination on retrobulbar blood flow in patients with ocular hypertension (OHT). PATIENTS AND METHODS: Twenty consecutive patients with OHT were prospectively randomised to either bimatoprost/timolol or placebo during a 12 weeks double masked treatment trial. Examinations were performed at baseline and after 12 weeks of treatment. Visual acuity, intraocular pressure (IOP), slit-lamp examination, automated static perimetry, systemic blood pressure and heart rate were all recorded. Retrobulbar blood flow measurements of the ophthalmic artery (AO) and central retinal artery (CRA) were measured by colour Doppler imaging. RESULTS: IOP was significantly decreased by bimatoprost/timolol fixed combination (p < 0.0001). Bimatoprost/timolol fixed combination therapy resulted in a significant increase in end diastolic velocity (EDV) of the CRA (p = 0.03). In patients treated with bimatoprost/timolol a statistically significant correlation between IOP and EDV was observed after 12 weeks of treatment (r = -0.511, p = 0.045). The systolic (p = 0.54) and diastolic (p = 0.67) blood pressures and heart rate (p = 0.10) did not show statistically significant differences during the study period. CONCLUSIONS: Topical bimatoprost/timolol fixed combination significantly reduced IOP in patients with OHT. However, the only significant change observed in retrobulbar haemodynamics was an increase in EDV of the CRA, probably associated with a reduction in IOP.

Evaluación mediante ecografía doppler color del efecto de la combinación fija bimatoprost/timolol sobre el flujo sanguíneo ocular en pacientes con hipertensión ocular. Estudio preliminar / Evaluation of the effect of bimatoprost/timolol fixed combination on ocular blood flow in patients with ocular hypertension using colour Doppler imaging. Preliminary study

Objetivo: Evaluar el efecto de la administración tópica de la combinación fija bimatoprost(0,3 mg/ml)/maleato de timolol (5 mg/ml) sobre el flujo sanguíneo retrobulbar en pacientescon hipertensión ocular (HTO).Pacientes y métodos: Veinte pacientes con HTO fueron incluidos en este estudio prospectivo,doble ciego y aleatorizados a recibir tratamiento con bimatoprost/timolol o placebo durante12 semanas. Las pruebas se llevaron a cabo en la primera visita y a las 12 semanas. Seregistraron la agudeza visual, presión intraocular (PIO), examen en lámpara de hendidura,perimetría estática automática, presión arterial sistémica y frecuencia cardíaca. Medianteecografía doppler color (EDC) se midieron los parámetros del flujo sanguíneo retrobulbarde la arteria oftálmica (AO) y arteria central de la retina (ACR).Resultados: La combinación fija bimatoprost/timolol redujo significativamente la PIO(p < 0,0001), además de conseguir un incremento significativo de la velocidad diastólicafinal (VDF) en la ACR (p = 0,03). En el grupo de pacientes tratados con bimatoprost/timololse observó una correlación estadísticamente significativa entre la PIO y la VDF a las 12semanas de tratamiento (r = –0,511, p = 0,045). No hubo cambios significativos en las presionesarteriales sistólica (p = 0,54) y diastólica (p = 0,67) ni en la frecuencia cardíaca(p = 0,10) durante el período de tratamiento.Conclusiones: La combinación fija bimatoprost/timolol redujo significativamente la PIO enpacientes con HTO. El único cambio observado en la hemodinámica retrobulbar fue unincremento de la VDF en la ACR, probablemente relacionado con la reducción de la PIO(AU)

Purpose: To investigate the effects of topical bimatoprost (0.3 mg/ml)/timolol maleate (5 mg/ml) fixed combination on retrobulbar blood flow in patients with ocular hypertension(OHT).Patients and methods: Twenty consecutive patients with OHT were prospectively randomisedto either bimatoprost/timolol or placebo during a 12 weeks double masked treatment trial.Examinations were performed at baseline and after 12 weeks of treatment. Visual acuity,intraocular pressure (IOP), slit-lamp examination, automated static perimetry, systemicblood pressure and heart rate were all recorded. Retrobulbar blood flow measurements ofthe ophthalmic artery (AO) and central retinal artery (CRA) were measured by colourDoppler imaging.Results: IOP was significantly decreased by bimatoprost/timolol fixed combination(p < 0.0001). Bimatoprost/timolol fixed combination therapy resulted in a significantincrease in end diastolic velocity (EDV) of the CRA (p = 0.03). In patients treated withbimatoprost/timolol a statistically significant correlation between IOP and EDV wasobserved after 12 weeks of treatment (r = –0.511, p = 0.045). The systolic (p = 0.54) anddiastolic (p = 0.67) blood pressures and heart rate (p = 0.10) did not show statisticallysignificant differences during the study period.Conclusions: Topical bimatoprost/timolol fixed combination significantly reduced IOP inpatients with OHT. However, the only significant change observed in retrobulbarhaemodynamics was an increase in EDV of the CRA, probably associated with a reductionin IOP(AU)

[Pars plana vitrectomy as anti-inflammatory therapy for intermediate uveitis in children]. / La vitrectomía como terapia antinflamatoria de la uveítis intermedia en niños.

PURPOSE: Intermediate uveitis represents between 2 and 26% of uveitis in children. The spectrum of the disease is highly variable, ranging between mild cases that resolve spontaneously and chronic, severe forms that develop multiple episodes and complications. The purpose of this study is to evaluate the efficacy of vitrectomy to control inflammation in children with recurrent intermediate uveitis. METHODS: Retrospective evaluation of patients with at least six months of follow-up. All patients under 16 who had undergone vitrectomy for intermediate uveitis were included. Vitrectomy was performed after at least two episodes of intermediate uveitis in children that had had no previous prophylactic systemic immunosuppressant treatment. Data recorded were visual acuity (VA), recurrences and surgical complications. RESULTS: Seven eyes of five children with intermediate uveitis who underwent vitrectomy were included. After a mean follow-up of 34 months, VA improved in all eyes after surgery. Four eyes developed mild subcapsular posterior cataracts. Post-surgical recurrences were anterior and responded to topical treatment, except for an episode of intermediate uveitis that required a periocular injection of triamcinolone. Only one patient is being treated with systemic immunosuppressants, due to the presence of repeated episodes of uveitis in the non-vitrectomised eye and since his parents were unwilling to have him undergo new surgery. CONCLUSIONS: Vitrectomy with inferior cryotheraphy controls inflammation in intermediate uveitis in children with good mid-term results avoiding the secondary side-effects of systemic immunosuppressants.

Mesenchymal stem cells facilitate the derivation of human embryonic stem cells from cryopreserved poor-quality embryos.

BACKGROUND: Human embryonic stem cells (hESCs) have opened up a new area of research in biomedicine. The efficiency of hESC derivation from frozen poor-quality embryos is low and normally achieved by plating embryos on mouse or human foreskin feeders (HFFs). We attempted to optimize embryo survival and hESC derivation. METHODS: Three conditions were tested on frozen poor-quality embryos: (i) embryo treatment with the Rho-associated kinase (ROCK) inhibitor, Y-27632; (ii) use of human mesenchymal stem cells (hMSCs) as feeders; and (iii) laser drilling (LD) for inner cell mass (ICM) isolation. Two hundred and nineteen thawed embryos were randomly treated with (n = 110) or without (n = 109) 10 microM Y-27632. Surviving embryos that developed to blastocyst stage (n = 50) were randomly co-cultured on HFFs (n = 21) or hMSCs (n = 29). ICM isolation was either by whole-blastocyst culture (WBC) or WBC plus LD. RESULTS: Embryo survival was 52% higher with Y-27632. hMSCs appeared to facilitate ICM outgrowth and hESC derivation: three hESC lines were derived on hMSCs (10.3% efficiency) whereas no hESC line was derived on HFFs. ROCK inhibition and ICM isolation method did not affect hESC efficiency. The lines derived on hMSCs (AND-1, -2, -3) were characterized and showed typical hESC morphology, euploidy, surface marker and transcription factor expression and multilineage developmental potential. The hESC lines have been stable for over 38 passages on hMSCs. CONCLUSION: Our data suggest that Y-27632 increases post-thaw embryo survival and that hMSCs may facilitate the efficiency of hESC derivation from frozen poor-quality embryos.

Optic disc cupping after optic neuritis evaluated with optic coherence tomography.

PURPOSE: To determine whether the optic disc experiences cupping after an episode of optic neuritis as assessed by optical coherence tomography (OCT). METHODS: A total of 50 patients with unilateral optic neuritis and 50 age- and sex-matched controls were studied. A complete examination, including visual acuity (VA), visual fields, and OCT scanning of the optic nerve head was performed. Mean cup-to-disc (C/D) ratios in the affected eyes were compared with fellow and control eyes. RESULTS: Mean C/D area ratio (CDAR), C/D vertical ratio (CDVR), and C/D horizontal ratio (CDHR) were significantly larger in the affected eyes compared to fellow (P<0.001) and control eyes (P<0.05). The asymmetry in CDAR, CDVR, and CDHR between both eyes in the patients with optic neuritis was equal to or greater than 0.2 in 24, 28, and 30% respectively. A significant inverse correlation was found between the C/D ratios asymmetry and retinal nerve fibre layer (RNFL) thickness (P<0.05). CONCLUSION: A significant increase in C/D ratio can be detected by OCT after unilateral optic neuritis, inversely correlated with RNFL thickness, and VA.

L1Tc non-LTR retrotransposons from Trypanosoma cruzi contain a functional viral-like self-cleaving 2A sequence in frame with the active proteins they encode.

A comparative analysis of 40 Trypanosoma cruzi L1Tc elements showed that the 2A self-cleaving sequence described in viruses is present in them. Of these elements, 72% maintain the canonical 2A motif (DxExNPGP). A high percentage has a conserved point mutation within the motif that has not been previously described. In vitro and in vivo expression of reporter polyproteins showed that the L1Tc2A sequence is functional. Mutations within certain L1Tc2A sequences affect the efficiency of the cleavage. The data indicate that the L1Tc2A sequence may be influencing the L1Tc enzymatic machinery determining the composition and level of the translated products. The residues located immediately upstream of the 2A consensus sequence increase the cleaving efficiency and appear to stabilize the relative amount of translated products.

Identificación in silico, caracterización molecular y análisis de expresión de la proteína de filamento para flagelar PFR3 del Tripanosoma brucei / Silico identification, molecular characterization and expression analysis of the Trypanosoma brucei paraflagellar rod protein PFR3

En el presente artículo se describen la identificación y el aislamiento del gen codificante para la proteína PFR3 del T. brucei brucei. . La secuencia deducida de aminoácidos produce una proteína de 592 residuos con un punto isoeléctrico de 5,14 y presenta una identidad de secuencia del 68,9% con la proteína PFR3 del T. cruzi cruzi. . Sin embargo, el porcentaje de homología entre la proteína PFR3 de T. brucei y otras secuencias disponibles de PFRs de T. brucei y T. cruzi es inferior al 22%. En contraste con lo descrito para los miembros de la familia de proteínas de filamento paraflagelar, la mayor divergencia entre las proteínas PFR3 de T. cruzi y T. brucei se encuentra en la región central de la proteína, con una similitud del 38% en 200 aminoácidos. Estimamos que existen dos copias de la proteína PFR3 de T. brucei por genoma haploide. El gen se transcribe como mARN de aproximadamente 3,6 kb de longitud, presente con la misma abundancia en formas parasitarias procíclicas y del torrente sanguíneo

In the present paper we describe the identification and isolation of the gene coding for T. brucei PFR3 protein. The deduced amino acid sequence produces a protein of 592 residues with an isoelectric point of 5.14 and shows a 68.9% sequence identity with T. cruzi PFR3 protein. However, the percentage of homology among T. brucei PFR3 and other available PFRs sequences from T. brucei and T. cruzi is lower than 22%. In contrast to that described for members of paraflagellar rod protein family, the highest divergence between T. cruzi and T. brucei PFR3 proteins is located at the central region of the protein with a 38% of similarity over 200 amino acid. We estimate that there exist two copies of the T. brucei PFR3 protein per haploid genome. The gene is transcribed as a mRNA of approximately 3.6 kb in length, equally abundant in both procyclic and bloodstream parasite forms

Characterization of reverse transcriptase activity of the L1Tc retroelement from Trypanosoma cruzi.

The recombinant protein RTL1Tc, encoded by the non-LTR (long terminal repeat) retrotransposon L1Tc from Trypanosoma cruzi, has been shown to have reverse transcriptase (RT) activity using poly(rA)/oligo(dT) and poly(rC)/oligo(dG) homopolymers as template/primers. The optimal RT activity was detected at a concentration of 5 mM Mg2+, pH 8 and between 28 and 37% degrees C. Site-directed mutagenesis in the RT catalytic site proved that substitution of aspartic acid 313 for isoleucine (RT D313IL1Tc) practically abolishes the RT activity of the RTL1Tc protein. RT-polymerase chain reaction assays revealed that the RTL1Tc protein has the ability to use both homologous and heterologous RNA templates. Also, it is shown that the RTL1Tc protein is capable of synthesizing complementary DNA molecules by consecutive switching of the oligo molecule, which the protein uses as a template. This template switching may be involved in the retroelement integration process.

The endonuclease NL1Tc encoded by the LINE L1Tc from Trypanosoma cruzi protects parasites from daunorubicin DNA damage.

In the present paper we show that the overexpression of the NL1Tc protein, encoded by the L1Tc non-LTR retrotransposon from Trypanosoma cruzi, led to a reduction of about 60% of DNA damage caused by daunorubicin treatment. This repair effect is not observed in transfected parasites overexpressing the NL1Tc mutated in the aspartic acid located in the active site of the enzyme. In addition, NL1Tc overexpression protects the parasite from the negative effect that daunorubicin has on parasite's growth rate. Thus, parasites overexpressing NL1Tc show, after treatment with 4 microM of daunorubicin, growth rate two to three times higher than the growth rate observed in treated control parasites transformed with the empty vector or overexpressing the mutated NL1Tc. Likewise, parasites overexpressing the NL1Tc protein and irradiated with a single dose of gamma-radiation (6 or 9 Gy) show higher growth rates than the parasites overexpressing the mutated NL1Tc or the control transfected parasites.

Genomic clustering of the Trypanosoma cruzi nonlong terminal L1Tc retrotransposon with defined interspersed repeated DNA elements.

We have analyzed the genomic distribution and organization of the long interspersed nucleotide element (LINE) L1Tc, a nonlong terminal repeat (LTR) retrotransposon of Trypanosoma cruzi. The results indicate that the L1Tc element is dispersed along the parasite genome and that in some regions it is organized in tandem repeats. The data allowed us to define the existence of short direct-repeated sequences flanking the genomic L1Tc elements. Relevant is the finding that the LINE L1Tc is located in genomic regions rich in short interspersed nucleotide elements (SINE)-like sequences. In particular, the L1Tc element is found associated to E13-related sequences, redefined in this work and renamed RS13Tc, and to a newly described RS1Tc sequence. The RS1Tc sequence is present, per haploid genome, in about 3,200 copies. Northern blot analysis showed that the RS1Tc is being transcribed into RNAs of different sizes. The analysis of the chromosomal distribution of these elements in various strains of T. cruzi suggested that this type of clustering might be a common feature of the genome of these parasites.

Molecular characterization of KMP11 from Trypanosoma cruzi: a cytoskeleton-associated protein regulated at the translational level.

Kinetoplasmid membrane protein-11 (KMP11) is present in a wide range of trypanosomatids. In the present paper, we show that the T. cruzi KMP11 gene is organized in a cluster formed by four gene units arranged in a head-to-tail tandem manner located on a chromosome of about 1900 kb. Northern blot analyses indicated that the steady-state level of mature KMP11 transcripts of 0.52 kb is high and similar in the three forms of the parasite. The KMP11 mRNAs have a half-life of about 16 h whose steady-state level is strongly downregulated when the parasites reach the stationary growth phase. The T. cruzi KMP11 sequence presents a significant homology with the amino-terminal third of the cytoskeleton-associated protein CIP1 from Arabidopsis thaliana. Western blot and immunoelectron microscopy studies showed that KMP11 is present in the cytoskeleton structure. Because the strong downregulation observed in the de novo synthesis of KMP11 protein in parasites treated with vinblastine is not accompanied by a significant fall in the steady-state level of KMP11 mRNAs, regulatory control of the protein at the translational level is suggested.