Search

In proliferative diabetic retinopathy (PDR), retinal ischemia promotes neovascularization (NV), which can lead to profound vision loss in diabetic patients. Treatment for PDR, panretinal photocoagulation, is inherently destructive and has significant visual consequences. Therapies targeting vascular endothelial growth factor (VEGF) have transformed the treatment of diabetic eye disease but have proven inadequate for treating NV, prompting exploration for additional therapeutic options for PDR patients. In this regard, extracellular proteolysis is an early and sustained activity strictly required for NV. Extracellular proteolysis in NV is facilitated by the dysregulated activity of matrix metalloproteinases (MMPs). Here, we set out to better understand the regulation of MMPs by ischemia in PDR. We demonstrate that accumulation of hypoxia-inducible factor-1α in Muller cells induces the expression of VEGF, which, in turn, promotes increased MMP-2 expression and activity in neighboring endothelial cells (ECs). MMP-2 expression was detected in ECs in retinal NV tissue from PDR patients, whereas MMP-2 protein levels were elevated in the aqueous of PDR patients compared with controls. Our findings demonstrate a complex interplay among hypoxic Muller cells, secreted angiogenic factors, and neighboring ECs in the regulation of MMP-2 in retinal NV and identify MMP-2 as a target for the treatment of PDR. Diabetes 62:3863-3873, 2013, Diabetic retinopathy (DR) is the most common microvascular complication in the diabetic population. Development of DR is directly related to the duration of diabetes; 20 years after diagnosis, nearly all [...]

The authors report the use of an adaptive optics (AO) system in an asymptomatic patient with small choroidal melanoma. A noninvasive, novel assessment that detected potential photoreceptor abnormalities in the retina overlying the choroidal lesion and adjacent retina is presented. These findings may help current clinical evaluation to monitor structural damage to the outer retina and possibly justify earlier intervention in borderline cases. Future research is warranted to recognize full potential of this imaging modality.[[Ophthalmic Surg Lasers Imaging Retina.2017;48:354–357.]

IMPORTANCE: Although mostly asymptomatic, patients with choroidal nevi carry a moderate risk for malignant transformation and visual loss. A novel noninvasive imaging assessment could change the current clinical evaluation of choroidal nevi. OBSERVATION: Three patients with a recent diagnosis of choroidal nevi underwent a novel adaptive optical assessment that detected potential photoreceptor abnormalities in the retina overlying the choroidal nevi. CONCLUSIONS AND RELEVANCE: Adaptive optics imaging may provide high-resolution en face images of retinal structural changes in the photoreceptor mosaic overlying the choroidal nevi. Cone attenuation may be an important component of structural damage in choroidal nevi and may correlate and possibly predict functional visual loss.

Although pulmonary tuberculosis is the most common form of this disease, neurotuberculosis is more severe and presents higher morbidity and mortality. Its diagnosis continues to challenge physicians all over the world. Contributing to this fact is the nonspecificity of its clinical manifestations, the low density of bacilli in the cerebrospinal fluid (CSF), and the delayed recovery of Mycobacterium tuberculosis through culture techniques. Thus, the diagnosis is largely based on suspicious symptoms, and the prognosis is directly related to the stage of the disease at the beginning of treatment. Even thought there is no consensus regarding the best therapeutic regimen, the WHO recommends using the same regimen used for pulmonary tuberculosis with a longer treatment time. It is important to note that in most cases, the doctor will not have a definite diagnosis at the beginning of the treatment. However, this should not delay the initiation of therapy. A delay in initiating treatment, in most cases, is directly associated with a poor prognosis. This review gives an overview of the current state of the neurotuberculosis research. It covers the epidemiological aspects of the infection, pathogenesis, principal clinical presentations, diagnosis highlighting neuroimaging, where a series of imaging are presented, prognosis, prevention and therapeutic regimens.

Focusing on the challenge of minimizing the level of stress to which cyclists are exposed to when cycling, the objective of this study is to assess the applicability of an important index to classify routes in terms of stress for cycling, the Level of Traffic Stress (LTS), to a medium-sized city in a developing country.

Introduction. Blue rubber bleb nevus syndrome is a rare disorder that is characterized by multiple recurrent vascular malformations that involve the skin and the gastrointestinal tract. The disease can present chronic anemia and severe episodes of gastrointestinal bleeding. Case Report. A 41-year-old man was admitted with recurrent episodes of lower gastrointestinal bleeding and anemia that had worsened over the last 3 months. The physical examination showed soft, diffuse, compressible, bluish nodules on all of the skin surfaces of the body. A biopsy from one of these skin lesions allowed a histological diagnosis of cavernous hemangioma. He submitted to a colonoscopy, which showed hemorrhoids and a plane vascular lesion mainly located on the right colon with recent signs of bleeding; this lesion was treated by local excision and sclerosis. The pathological study of the colon specimens also reflected the presence of cavernous hemangioma. The cutaneous hemangiomas and the presence of colonic venous malformations were compatible with blue rubber bleb nevus syndrome. The patient presented a favorable follow-up with clinical control of the anemia and without relapse of the gastrointestinal bleeding two years after the procedure. Conclusion. Although rarely diagnosed, blue rubber bleb nevus syndrome may be responsible for lower digestive bleeding.