The potential of stem cell (SC) therapies for eye diseases is well-recognized. However, the results remain only encouraging as little is known about the mechanisms responsible for eye renewal, regeneration and/or repair. Therefore, it is critical to gain knowledge about the specific tissue environment (niches) where the stem/progenitor cells reside in eye. A new type of interstitial cell–telocyte (TC) (http://www.telocytes.com) was recently identified by electron microscopy (EM). TCs have very long (tens of micrometres) and thin (below 200 nm) prolongations named telopodes (Tp) that form heterocellular networks in which SCs are embedded. We found TCs by EM and electron tomography in sclera, limbus and uvea of the mouse eye. Furthermore, EM showed that SCs were present in the anterior layer of the iris and limbus. Adhaerens and gap junctions were found to connect TCs within a network in uvea and sclera. Nanocontacts (electron-dense structures) were observed between TCs and other cells: SCs, melanocytes, nerve endings and macrophages. These intercellular ‘feet’ bridged the intercellular clefts (about 10 nm wide). Moreover, exosomes (extracellular vesicles with a diameter up to 100 nm) were delivered by TCs to other cells of the iris stroma. The ultrastructural nanocontacts of TCs with SCs and the TCs paracrine influence via exosomes in the epithelial and stromal SC niches suggest an important participation of TCs in eye regeneration.

Blood vessels are highly organized and complex structure, which are far more than simple tubes conducting the blood to almost any tissue of the body. The fine structure of the wall of blood vessels has been studied previously using the electron microscope, but the presence the telocytes associated with vasculature, a specific new cellular entity, has not been studied in depth. Interestingly, telocytes have been recently found in the epicardium, myocardium, endocardium, human term placenta, duodenal lamina propria and pleura. We show the presence of telocytes located on the extracellular matrix of blood vessels (arterioles, venules and capillaries) by immunohistochemistry and transmission electron microscopy. Also, we demonstrated the first evidence of a primary cilium in telocytes. Several functions have been proposed for these cells. Here, the telocyte-blood vessels cell proximity, the relationship between telocytes, exosomes and nervous trunks may have a special significance.

It was 50 years ago when the details of cellular structure were first observed with an electron microscope (EM). Today, transmission electron microscopy (TEM) still provides the highest resolution detail of cellular ultrastructure. The existence of telocytes (TCs) has been described by Hinescu and Popescu in 2005 and up to now, many studies have been done in different tissues. EM has been fundamental in identification and recognition of TC and relationship between TC and stem cells (SCs) in recent years. We present a review on the importance of TEM to provide major advances in the knowledge of the biology of these cells.

Extracellular vesicles (EVs) have emerged as an intercellular communication mediator in cancer. They seem to be involved in tumor processes by means of transformation of surrounding cells previous to metastasis by transferring miRNAs and oncogenic proteins. It is known that EVs, depending on their source, can be exosomes or ectosomes. Although the first type constitutes a specific population formed from the endosomal system, via multivesicular bodies, the ectosome biogenesis is not yet well known. In this study, we report a new type of EVs which has been termed spheresomes. While exosomes come from multivesicular bodies and ectosomes from direct budding of plasma membrane, spheresomes present a new mechanism of shedding from a spherical membrane structure which we have named multivesicular spheres. These EVs are first described in gastrointestinal stromal tumor cells in the present study. But moreover, these new membrane spherical structures appear not only next to tumoral cells but also different distances from them. Since some other authors have evidenced oncogenic KIT-containing EVs, it is also suggested here that surrounding cells uptake of these first described EVs, GIST-derived spheresomes, could induce tumor invasiveness. That is why the prevention of signaling processes developed by these new EVs may represent an alternative approach for GIST treatment.

Gastrointestinal stromal tumours (GISTs) are the most common mesenchymal (non-epithelial) neoplasms of the human gastrointestinal (GI) tract. They are thought to derive from interstitial cells of Cajal (ICCs) or an ICC progenitor based on immunophenotypical and ultrastructural similarities. Because ICCs show primary cilium, our hypothesis is based on the possibility that some of these neoplastic cells could also present it. To determine this, an exhaustive ultrastructural study has been developed on four gastric GISTs. Previous studies had demonstrated considerable variability in tumour cells with two dominating phenotypes, spindly and epithelioid. In addition to these two types, we have found another cell type reminiscent of adult ICCs with a voluminous nucleus surrounded by narrow perinuclear cytoplasm with long slender cytoplasmic processes. We have also noted the presence of small undifferentiated cells. In this study, we report for the first time the presence of primary cilia (PCs) in spindle and epithelioid tumour cells, an ultrastructural feature we consider of special interest that has hitherto been ignored in the literature dealing with the ultrastructure of GISTs. We also point out the frequent occurrence of multivesicular bodies (MVBs). The ultrastructural findings described in gastric GISTs in this study appear to be relevant considering the critical roles played by PCs and MVBs recently demonstrated in tumourigenic processes.

Background: We aimed to determine the physiological symmetry, with spectral-domain optical coherence tomography, of choroidal measurements in a healthy population in all the areas defined in the Early Treatment Diabetic Retinopathy Study (ETDRS). Methods: One hundred and fifty-four eyes of 77 healthy young adults between the ages of 19 and 32 years were enrolled. Differences in choroidal thickness (CT) and volume (CV) between the left and right eyes were calculated. Normal ranges of absolute interocular differences were established as the 95th percentile. Results: The mean ± SD subfoveal CT (SFCT) and total CV values in the right and left eyes were 342.03 ± 77.38 versus 361.64 ± 76.45 µm (correlation coefficient ρ = 0.820; p < 0.001) and 0.27 ± 0.06 versus 0.28 ± 0.06 mm³ (ρ = 0.830; p < 0.001), respectively. Differences in 5 of the 9 areas of the ETDRS map were statistically significant (p < 0.05), but with a strong interocular correlation (ρ > 0.8; p < 0.001). The 95th percentile of interocular tolerance limits for CT in the 1-, 3-, and 6-mm areas were 97, 70, and 57 μm, respectively; the 95th percentile for the volume values were 0.06, 0.51, and 1.73 mm³. Conclusions: CT and CV are highly correlated between eyes, statistically significant differences between them can be found, and absolute interocular differences may reach 97 µm in SFCT, and 1.73 mm³ in total CV.

Amputation represents a drastic impact on the patient’s body and perception. This cross-sectional study aims to analyse the aesthetic concern represented by body image, self-esteem and quality of life in patients with unilateral transtibial amputations of lower limbs compared to control group. People living with amputations present lower average levels than controls in all subscales of the SF-36 (Short Form 36 Health Survey) quality of life questionnaire, and in both the physical component summary and the mental component summary, although the difference is not statistically significant in the latter. These patients present a significantly lower mean score (p = 0.002) in the MBSRQ (Body-Self Relations Questionnaire) body image questionnaire: 2.64 ± 0.49 opposed to 3.16 ± 0.55 in controls. People living with amputations had a lower mean score on the Rosenberg Self-Esteem scale than controls (34.44 ± 4.61 v 36.04 ± 3.63). The results also show that amputation has a significant influence on the BI (Body image) of patients with unilateral transtibial amputations. SE (Self-Esteem) seems to be an aspect that is not significantly affected by lower limb amputation, although these patients scored a lower mean on the RSE scale compared to the control group. We consider it is highly relevant to assess QoL (Quality of life), BI and SE in patients after a lower limb amputation process.

IntroductionThe prevalence of obesity has increased exponentially in recent decades, being one of the diseases that most affects global health. It is a chronic disease associated with multiple comorbidities, which lead to a decrease in life expectancy and quality of life. It requires a multidisciplinary approach by a specialized medical team. Obesity can be treated with conservative or with surgical treatments that will depend on the characteristics of the patient.Objective/MethodologyThe referenced surgery can be performed using different surgical techniques that are analyzed in the present work through an exhaustive narrative bibliographic review in the PubMed and Cochrane databases, as well as in UpToDate.ResultsCurrently, those most used are restrictive techniques, specifically vertical gastrectomy and mixed techniques, with gastric bypass being the “gold standard”.ConclusionsIn order to choose one technique or another, the characteristics of each patient and the experience of the surgical team must be taken into account.