The pathophysiology of Type 1 diabetes (T1D) appears largely related to an innate defect in the immune system culminating in a loss of self tolerance and destruction of the insulin producing β-cells. Currently, there is no definitive cure for diabetes. Insulin injection does not mimic the precise regulation of β-cells on glucose homeostasis, leading long term to the development of complications. Other therapeutic approaches therefore, are necessary and cell therapy is thought to be a possible approach. In this sense, mesenchymal stem cells (MSCs) can offer a promising possibility that deserves to be explored. MSCs are multipotent non-hematopoietic progenitor cells. Their therapeutic potentials have recently been brought into the spotlights of many fields of research. Although the regenerative capabilities of MSCs have been a driving force to initiate studies testing their therapeutic effectiveness, their immunomodulatory properties have been equally exciting. MSCs possess specific immunomodulatory properties that would appear capable of disabling immune dysregulation that leads to β-cell destruction in T1D. Furthermore, MSCs can be sequentially cultured in specially defined conditions and their differentiation extends toward the β-cell phenotype and the formation of insulin producing cells (IPCs). To date, the role of MSCs in T1D remains completely unexplored. We herein summarize multiple strategies that have been proposed and tested for its potential therapeutic benefit for T1D.

AimTo record ocular vascular events following injections of vascular endothelium growth factor (VEGF) antagonists.MethodsCollaborative multicenter case series (48 cases), literature reviews (32 cases), and reports to the FDA (64 cases) of patients that had vascular occlusions during anti-VEGF therapy were collected and analyzed.ResultsA total of 144 cases of ocular vascular events were identified, with these diagnosed a median of 15 days after anti-VEGF injection. The majority of patients had pre-existing risk factors for cardiovascular events and nine patients had a prior history of glaucoma. Mean visual acuity dropped by 6.4 lines with severe visual loss after injection to NLP (five eyes), LP (six eyes), and HM (two eyes). The overall risk of ocular vascular events following a VEGF antagonist injection was 0.108% in the general population and 2.61% in the diabetic population. Mean retinal arterial constriction after intravitreal bevacizumab in 13 eyes was 21% (standard deviation = 27%), and mean retinal venous constriction was 8% (standard deviation = 30%).ConclusionOcular vascular events are rare during anti-VEGF therapy, but can lead to severe visual loss and may be caused by a number of factors including the vasoconstrictor effect of the drug, a post-injection rise of intraocular pressure, patient stress as a result of the procedure, and the patient’s natural history of underlying ocular or systemic diseases. The diabetic population appears to have a tendency towards ocular vascular occlusions.

Intravitreal diclofenac is effective in the treatment of diffuse diabetic macular edema up to 12 weeks. Intravitreal triamcinolone and diclofenac appear to have comparable therapeutic effects on retinal thickness. The degree of visual improvement is higher with triamcinolone.

Aplastic anemia (AA) is a rare disease with few reports on its ophthalmic manifestations. The ocular findings are described in a retrospective consecutive series of 719 AA Korean patients followed at the Hematology Clinic of The Catholic University of Korea. Out of a total of 719 patients, 269 patients had eye examinations, 156 patients had retinal evaluation, and 37 (23.7%) had retinal findings. These 37 patients had unilateral retinal hemorrhage in seven and bilateral retinal hemorrhage in 30 with mean hemoglobin of 6.6 g/dL (range 2.7–12.6 g/dL) and platelet counts of 18.8×109/L (range 4–157×109/L); central retinal vein occlusion-like picture occurred in nine patients and these had similar rheology to the rest of the subjects; optic disc edema, cotton-wool spots, macular edema, and dry eyes occurred in two, three, five, and three patients, respectively. In this Korean series of 141 subjects with AA, systemic bleeding occurred in 24.8% of subjects, retinal hemorrhage in 37% of subjects, and any bleeding site (eye or elsewhere) occurred in 47.5% of subjects with AA. A literature review (1958–2010) of 200 AA cases revealed retinal hemorrhages in 56%, subhyaloid or vitreous hemorrhage in 9%, peripheral retinal vasculopathy in 5.5%, and cotton-wool spots, Sjögren’s syndrome, or optic disc edema in 4% each. The prevalence of retinopathy among series of AA patients varied from 20% to 28.3%, which is consistent with the Korean series of 24.8%. Management of AA patients needs to involve multiple specialties, including hematologists, ophthalmologists, and infectious disease specialists.

Poly-3-hydroxy butyrate has been etched and studied under scanning and transmission electron microscopes. It displays three of the following unusual features:(1) spherulites develop in a loose spiral rather than radial structure, which appears to reflect the chiral nature of the polymer; (2) in the banded spherulitic structure, lamellae oriented flat-on to the surface are etched more deeply in relation to edge-on lamellae; and (3) material crystallized at high temperature is less resistant to etching than that crystallized at low temperature, whereas the most rapid rate of etching appears to be where growth occurred at an intermediate temperature where the growth rate was at its maximum. The second and third phenomena are contrary to what is found in polymers such as polyethylene and polyethylene terephthalate and are attributed to excess free volume in the material located between the main lamellar bundles. Polyoxymethylene also displays the same unusual relationship of etching rate with crystallization temperature.