Resultados a largo plazo del tratamiento de la degeneración macular asociada a la edad neovascular mediante fármacos antiangiogénicos: revisión de la bibliografía / Long-term results of treatment of neovascular age-related macular degeneration using antiangiogenic drugs: A review of the literature

La degeneración macular asociada a la edad (DMAE) constituye una de las principales causas de la pérdida de agudeza visual (AV) en los mayores de 50 años en el mundo, siendo la DMAE neovascular (DMAEn) la causante del 80% de los casos de pérdida de visión severa debido a esta enfermedad. Hace ya más de una década que se emplean los fármacos antifactor de crecimiento del endotelio vascular (anti-VEGF) para el tratamiento de esta enfermedad, cambiando drásticamente el pronóstico visual de estos pacientes. Sin embargo, los primeros estudios de los que se disponían datos de los resultados eran a corto plazo. En la actualidad existen ya diferentes series publicadas de los resultados de la DMAE a largo plazo tras el tratamiento con anti-VEGF, siendo el objetivo de la presente revisión sintetizar dichos resultados. El seguimiento medio de los estudios incluidos fue de 8,2 años (rango: 5-12 años). La AV inicial media fue 55,3 letras del Early Treatment Diabetic Retinopathy Study (ETDRS) (rango: 45,6-65) siendo la AV final media 50,1 letras (rango: 33,0-64,3), existiendo una pérdida media de 5,2 letras. Al final del seguimiento un 29,4% de los pacientes mantuvieron una AV>70 letras. El 67,9% de los pacientes se mantuvo estable al final del seguimiento (<15 letras de pérdida), existiendo una pérdida severa (≥15 letras) del 30,1%. La fibrosis y la atrofia fueron las principales causas de pérdida de AV a largo plazo, presentándose al final del seguimiento en un 52,5% y un 60,5%, respectivamente.(AU)

Age-related macular degeneration (AMD) is one of the main causes of visual acuity (VA) loss in people over 50 years of age worldwide, with neovascular AMD (nAMD) accounting for 80% of cases of severe vision loss due to this disease. Anti-vascular endothelial growth factor (anti-VEGF) drugs have been used for the treatment of this disease for more than a decade, changing drastically the visual prognosis of these patients. However, initial studies reporting data on outcomes were short term. Currently, there are different series published on the long-term results of AMD after treatment with anti-VEGF, and the aim of this review is to synthesize these results. The mean follow-up of the included studies was 8.2 years (range 5-12 years). The mean initial VA was 55.3 letters in the Early Treatment Diabetic Retinopathy Study (ETDRS) (range 45.6-65) and the mean final VA was 50.1 letters (range 33.0-64.3), with a mean loss of 5.2 letters. At the end of follow-up, 29.4% of the patients maintained a VA>70 letters. The 67.9% of patients remained stable at the end of follow-up (<15 letter loss), with a severe loss (≥15 letters) of 30.1%. Fibrosis and atrophy were the main causes of long-term VA loss, occurring at the end of follow-up in 52.5% and 60.5%, respectively.(AU)

Long-term results of treatment of neovascular age-related macular degeneration using antiangiogenic drugs: A review of the literature.

Age-related macular degeneration (AMD) is one of the main causes of visual acuity (VA) loss in people over 50 years of age worldwide, with neovascular AMD (nAMD) accounting for 80% of cases of severe vision loss due to this disease. Anti-vascular endothelial growth factor (anti-VEGF) drugs have been used for the treatment of this disease for more than a decade, changing drastically the visual prognosis of these patients. However, initial studies reporting data on outcomes were short term. Currently, there are different series published on the long-term results of AMD after treatment with anti-VEGF, and the aim of this review is to synthesize these results. The mean follow-up of the included studies was 8.2 years (range 5-12 years). The mean initial VA was 55.3 letters in the Early Treatment Diabetic Retinopathy Study (ETDRS) (range 45.6-65) and the mean final VA was 50.1 letters (range 33.0-64.3), with a mean loss of 5.2 letters. At the end of follow-up, 29.4% of the patients maintained a VA > 70 letters. The 67.9% of patients remained stable at the end of follow-up (< 15 letter loss), with a severe loss (≥ 15 letters) of 30.1%. Fibrosis and atrophy were the main causes of long-term VA loss, occurring at the end of follow-up in 52.5% and 60.5%, respectively.

Update on the utility of en face optical coherence tomography in the assessment of vitreoretinal diseases.

En face optical coherence tomography (EF-OCT) is a rapid, non-invasive, high-resolution imaging technique that has evolved in recent years to be a routine examination for the assessment and follow-up of various vitreoretinal diseases. With the introduction of swept-source OCT (SS-OCT), which can achieve up to 100,000 A-scans per second and better-quality imaging of deeper structures using a longer wavelength (1050nm), EF-OCT reconstruction can produce high-resolution frontal images of the retina and choroid (C-Scans) that give an overview of disease extent. These images allow a more accurate study of vitreoretinal interface pathologies such as epiretinal membranes, macular holes, and vitreomacular traction. They also provide key information in the study of various retinal vascular diseases and the differential diagnosis of cystic macular edema. EF-OCT provides valuable information about the severity of vitreoretinal interface alterations and precisely assesses the choriocapillaris and choroidal vasculature in pachychoroid disorders. Finally, this technique provides valuable information about atrophic and neovascular age-related macular degeneration and various uveitic entities. This review aims to describe the current clinical applications of EF-OCT in various vitreoretinal diseases as well as the latest findings and future perspectives.

Functional screening for cellulolytic activity in a metagenomic fosmid library of microorganisms associated with coral.

Cellulases are enzymes that degrade cellulosic materials. Cellulose is the most abundant renewable carbon resource on Earth, and cellulases are used in various industrial sectors. Although cellulases are obtained from a variety of sources, this is the first description of cellulolytic activity isolated from a coral metagenomic library. A metagenomic fosmid library of microorganisms associated with the coral Siderastrea stellata, comprising 3552 clones, was screened for cellulolytic activity; this allows access to non-cultivable microorganisms by exploiting the full biotechnological potential. Clones were grown on LB agar plates supplemented with 0.5% carboxymethylcellulose and cellulase positive clones revealed by staining with Congo red. Using this approach, six positive clones with cellulolytic activity were identified. The enzymatic index (EI) of the positive clones was calculated by the ratio between the hydrolysis zone diameter and colony diameter. All positive clones had an EI greater than 1.5. Digestion of the DNA isolated from the six positive clones, using the HindIII restriction endonuclease, revealed different restriction patterns in each clone, indicating that the DNA of each clone is different. There is a growing interest for new cellulolytic enzymes in various industry sectors. Here, we present the initial selection of potential clones for cellulose degradation that could be targets for future studies of enzymatic characterization.

Bacterial contamination of musculoskeletal allografts.

Based on the indications in the literature of the transmission of highly pathogenic bacteria in musculoskeletal allograft implants, the cultural results for allografts removed and implanted in conditions of asepsis between 1997 and 2000 in BTM were analyzed: 4014 allografts (3117 from a living donor, 897 from a cadaver) and 3479 implants (2191 with allografts from living donors and 1288 with allografts from cadavers). Explanted tissues: these were positive to culture in 292 out of 3117 (9.4%) allografts from living donors; the bacteria isolated showed low pathogenicity. Out of 897 allografts 117 cadaver donors bacteria with low pathogenicity were isolated in 68 (7.6%) and high pathogenicity in 12 (1.3%). Implants: cultures were positive in 116/2191 (5.3%) implants with allografts from living donors and in 55/1288 (4.3%) implants with allografts from cadavers. The bacteria isolated are the same as those shown in the explants. In living donors contamination is similar as regards incidence and type of microorganism to that observed in surgical theatres during routine surgery. Contamination seems to be greater in allografts removed from cadavers who died as a result of trauma, in the presence of positive hemocultures, prolonged catheterization and intubation, explantation of the pelvis and removal of several organs and tissues prior to musculoskeletal allograft.

Actin monoubiquitylation is induced in plants in response to pathogens and symbionts.

Most dramatic examples of actin reorganization have been described during host-microbe interactions. Plasticity of actin is, in part, due to posttranslational modifications such as phosphorylation or ubiquitylation. Here, we show for the first time that actins found in root nodules of Phaseolus vulgaris are modified transiently during nodule development by monoubiquitylation. This finding was extended to root nodules of other legumes and to other plants infected with mycorrhiza or plant pathogens such as members of the genera Pseudomonas and Phytophthora. However, neither viral infections nor diverse stressful conditions (heat shock, wounding, or osmotic stress) induced this response. Additionally, this phenomenon was mimicked by the addition of a yeast elicitor or H2O2 to Phaseolus vulgaris suspension culture cells. This modification seems to provide increased stability of the microfilaments to proteolytic degradation and seems to be found in fractions in which the actin cytoskeleton is associated with membranes. All together, these data suggest that actin monoubiquitylation may be considered an effector mechanism of a general plant response against microbes.

Short-term feeding of atherogenic diet to mice results in reduction of HDL and paraoxonase that may be mediated by an immune mechanism.

Short-term feeding (up to 7 days) of an atherogenic diet to C57BL/6 low density lipoprotein receptor-deficient mice did not result in decreased hepatic paraoxonase (PON) mRNA but caused a dramatic decrease in plasma PON activity and mass. The decreased activity and mass were temporally related to an increase in plasma and high density lipoprotein (HDL) lipid hydroperoxides and to a decrease in HDL cholesterol and native apolipoprotein A-I (apoA-I) and apolipoprotein A-II (apoA-II). As the native apoA-I protein disappeared from the circulation, higher molecular weight forms of apoA-I appeared, some of which contained epitopes recognized by an antibody (EO6) that recognizes oxidized phospholipids. After mice consumed an atherogenic diet for 1 or 3 days, switching the mice to a low fat chow diet for 3 days resulted in a return to baseline levels of lipid hydroperoxides but only a small return toward baseline for HDL cholesterol, with no significant increase in apoA-I mass or PON activity and mass. After mice consumed an atherogenic diet for 3 days, switching to the chow diet for 3 days did not significantly alter the high molecular weight forms of apoA-I or the signal generated by EO6. In marked contrast, after mice consumed an atherogenic diet for 7 days, switching to the chow diet for 3 days resulted in a dramatic increase in native apoA-I to baseline levels, with virtual disappearance of the high molecular weight forms of apoA-I, including the form recognized by EO6. After mice consumed an atherogenic diet for 7 days, switching to the chow diet for 3 days also resulted in significant increases in HDL cholesterol and PON mass and activity, although baseline levels were not reached. IgG and IgM antibodies were found to be associated with apoA-I in control animals, were minimally decreased after the 3-day atherogenic diet, were dramatically decreased after the 7-day atherogenic diet, and returned to near or above baseline levels after a return to the chow diet for 3 days. We conclude that the atherogenic diet rapidly induces lipid hydroperoxide formation and apoA-I oxidation with the formation of high molecular weight forms of apoA-I. Concomitant with these changes in apoA-I levels, HDL cholesterol and PON activity and mass declined without changes in mRNA levels for apoA-I or PON, suggesting increased clearance of these altered HDL particles. We further conclude that between the third and seventh day of the atherogenic diet, an as-yet-unidentified mechanism for clearing the high molecular weight forms of apoA-I is induced and that this mechanism may be related to the clearance of immune complexes.

Open-ring imaging sign: highly specific for atypical brain demyelination.

OBJECTIVE: To test the specificity for demyelination of a new neuroimaging sign: contrast enhancement shaped as an open ring or a crescent circumscribed to the white matter. BACKGROUND: Brain demyelination can cause ring enhancement mimicking neoplasm or infection on CT or MRI. METHODS: A MEDLINE search of pathology-proved demyelination yielded 32 illustrated cases of ring-enhancing lesions published between 1981 and 1995. Controls consisted of the same number of published images of neoplasms and infections, pathology proved, and matched by year of publication, and age and gender of the patient. Two neuroradiologists read the images twice independently 1 year apart. RESULTS: Interrater agreement was good (kappa = 0.64 and 0.66 for either reading). Test-retest reliability was high (kappa = 0.75 and 0.74 for either rater). The open-ring sign clearly distinguished demyelinating lesions from neoplasms and infections. For demyelination versus neoplasm or infection, the specificity of the reading by the first neuroradiologist was 93.8 (95% CI, 86 to 98), and that of the second was 84.4 (95% CI, 74 to 92). The likelihood ratio of demyelination versus neoplasm averaged 5.2, and versus infection, 17.2. That is, if the lesions had the same incidence in the population, in the presence of an open-ring sign demyelination would be five times more likely than neoplasm and 17 times more likely than infection. However, given the much higher incidence of neoplasms and infections, these lesions are still frequently responsible for open-ring enhancement. CONCLUSIONS: The open-ring sign is often present in large, contrast-enhancing demyelinating lesions and helps to differentiate them from neoplasms and infections.

Posttraumatic delayed sleep phase syndrome.

Circadian rhythm sleep disorders may occur after traumatic brain injury. We describe a 48-year-old man who presented with sleep onset insomnia and cognitive dysfunction after a car accident. A diagnosis of delayed sleep phase syndrome (DSPS) was confirmed by sleep logs and actigraphy, which revealed sleep onset in the early morning hours and awakening around noon.

Rhizobium nod factors induce increases in intracellular free calcium and extracellular calcium influxes in bean root hairs

Application of Nod factors to growing, responsive root hairs of the bean Phaseolus vulgaris induces marked changes in both the intracellular cytosolic free calcium (Ca2+) and in the influx of extracellular [Ca2+]. The intracellular [Ca2+], which has been measured by ratiometric imaging in cells microinjected with fura-2-dextran (70 kDa), elevates within 5 min from approximately 400 nM to 1500 nM in localised zones in the root hair apex. Of particular note is the observation that the elevated regions of [Ca2+] appear to shift position during short time intervals. Increases in and fluctuations of the intracellular [Ca2+] are also observed in the perinuclear region after 10-15 min treatment with Nod factors. The extracellular Ca2+ flux, detected with the non-invasive, calcium specific vibrating electrode, is inwardly directed and also increases quickly in response to Nod factors from 13 pmol cm-2 s-1 to 28 pmol cm-2 s-1. Chitin-oligomers, which are structurally similar but biologically inactive when compared to the active Nod factors, fail to elicit changes in either intracellular or extracellular Ca2+. The similar timing and location of the intracellular elevations and the increased extracellular influx provide support for the idea that Ca2+ participates in secretion and cell wall remodelling, which occur in anticipation of root hair deformation and curling.

Median and ulnar palm-wrist studies.

OBJECTIVES: Routine carpal tunnel electrodiagnosis frequently includes median (MPW) and ulnar (UPW) palm-wrist mixed nerve conduction latency determinations over 8 cm. Despite widespread use, normative palmar latency difference (PLD) and UPW values, and the relative utility of onset latency (OL) or peak latency (PL) measurements are controversial. The current study was conducted to determine normative values for these parameters. METHODS: MPW and UPW studies were performed unilaterally in 33 normal controls. The PLD-OL and PLD-PL were calculated. The mean, range, standard deviation, and upper limits of normal were determined. 74 hands (50 patients) with both clinical and electrophysiologic median neuropathy were also studied. RESULTS: The abnormal MPW and UPW cut-offs were both 1.8 ms (OL), and 2.3 ms (PL). The abnormal PLD cut-offs were 0.5 ms (OL and PL). Using either OL or PL, PLD parameters were similar within controls, and also within CTS patients. Using either OL or PL, UPW parameters were similar between controls and CTS patients. CONCLUSIONS: An abnormal PLD cut-off of 0.5 is recommended. This is slightly higher than some prior recommendations, however it should minimize the likelihood of false positive studies. Onset and peak latency measurements are likely to have similar clinical utility.

A rapid-cycling bipolar patient treated with long nights, bedrest, and light.

BACKGROUND: Stabilization of rapid-cycling bipolar disorder is extremely difficult. METHODS: A refractory bipolar I rapid-cycling patient on valproate was treated with long "nights" (extended sleep in darkness) and daytime light therapy. RESULTS: Rapid cycling immediately stopped on initiation of a 10 hour dark/rest period. This was extended to 14 hours (plus a self-selected 1 hour midday nap) without problems. Depression gradually improved when midday light therapy was added; near-euthymia was attained after light therapy was shifted to the morning. CONCLUSIONS: Nonpharmacological chronobiological treatments may be a means to interrupt rapid cycling.

Biological nitrogen fixation and future challenges of agriculture. The endophytic connection.

Feeding the growing global population, anticipated to be 8 billion by the year 2020, is one of the most important recent challenges of agriculture. The increase in cereal grain yield, to cope with this demand, directly implies a dramatic increase in the use of nitrogen-based fertilizers and agrochemicals. Some of these intensive agricultural practices have progressive detrimental effects on the environment. This review is focused on some novel insights gained into the understanding of associative and symbiotic interactions of plants with nitrogen-fixing organisms that makes Biological Nitrogen Fixation (BNF) a viable answer to this compelling dilemma.

Sensitive median-ulnar motor comparative techniques in carpal tunnel syndrome.

We describe two modified methods for median-to-ulnar motor conduction comparison in the diagnosis of median neuropathy at the wrist: the median-thenar to ulnar-thenar latency difference (TTLD), and the median-thenar to ulnar-hypothenar latency difference (THLD). We also describe an F-wave ulnar-to-median comparative test, the F-wave latency difference (FWLD). The abnormal cutoffs based upon 34 normal controls are: TTLD, 0.8 ms; THLD, 1.2 ms; FWLD, 0.6 ms. In 50 patients (79 hands) with clinically defined carpal tunnel syndrome and electrophysiological evidence of median neuropathy at the wrist (based upon a prolonged median nerve palm-wrist latency), the diagnostic sensitivities were: 95-98%, 85-88%, and 75-78%, respectively. These tests are therefore highly sensitive. They are easily performed and require minimal additional effort to incorporate into commonly used clinical electrodiagnostic routines. They may be advantageous when a concomitant polyneuropathy is present, and they may also help avoid technical pitfalls and aid in identification of anatomic variants.