Assessment of glioma proliferation using imaging modalities

The assessment of glioma proliferation rate is important to predict tumor behavior, response to therapy and prognosis. Various methods, largely involving immunohistological markers in tissue samples, have been proposed to this aim; however, they all require tissue removal through a biopsy or during a surgical procedure. Consequently, non-invasive imaging modalities that could reliably assess the proliferative potential of intracranial space-occupying lesions in vivo would be of obvious significance. In the present study we review the contribution of MRI, positron emission tomography and single-photon emission CT for the assessment of the proliferative potential of gliomas.     

A modified ETDRS visual acuity chart for European-wide use.

PURPOSE: The log MAR visual acuity (VA) chart developed for use in the Early Treatment Diabetic Retinopathy Study (ETDRS) is composed of 10 Sloan letters, which are not used in the Greek, Cyrillic, and Central European alphabets. In this study we evaluate a modified ETDRS chart, the University of Crete (UoC) chart, which contains a set of letters readable by all European citizens. METHODS: In the UoC charts, the letters C, D, R, N, V, S, and Z were substituted with E, P, B, X, Y, A, and T, respectively. The similarity between the modified and the standard acuity charts was evaluated using two procedures. First, VA of 227 secondary school children (454 eyes) was evaluated using both sets of charts. Second, the relative difficulty for the identification of individual Sloan letters used in both charts, as well as letter M, was assessed from psychometric functions for five subjects. RESULTS: Bland-Altman plots revealed no statistical significant differences in the value of VA between the standard and the UoC set of charts. Although, estimates of identification log MAR threshold showed relatively significant interletter variability, in total, the new set of Sloan letters was equally identifiable with the original set. CONCLUSIONS: The overall pattern of results suggests that the modified log MAR UoC charts forms a valid alternative to the ETDRS for assessing VA in multinational clinical trials, offering the advantage of containing letters recognizable by a wider population basis, such as European citizens, as well as subjects from countries using the Cyrillic alphabet.     

Immunohistochemical HLA-DR antigen expression with lymphocyte subsets and proliferative activity in pterygium

The immunohistochemical expression of HLA-DR antigen, CD8, CD4, CD68, S1OO, PCNA and Ki-67 was performed in order to investigate the role of immune mechanisms in pterygium, in correlation with proliferative activity. A series of 98 surgically-excised pterygia, 18 pingueculae and 20 normal conjunctivae, was studied by the avidin-biotin method, on formalin-fixed, paraffin-embedded tissue. HLA-DR antigen was abundantly expressed in pterygium epithelial cells, whereas almost no expression was found in pinguecula and normal conjunctiva. A high value of Ki-67 and PCNA expression coexisted in the same areas with HLA-DR antigen expression in pterygium and a statistically significant positive correlation resulted between them (p = 0.002). Aberrant infiltration of inflammatory cells (CD4, CD8, CD68, S100) was detected in pterygium, while lower densities were found in pinguecula and conjunctiva. The data suggest that immunopathological mechanisms may contribute in the pathogenesis of pterygium. In addition, the aberrant HLA-DR antigen expression seems to be correlated with the growth fraction of the lesion.     

Anticardiolipin antibodies levels in healthy pregnant and non-pregnant woman

To determine the prevalence of anticardiolipin antibodies in healthy non pregnant women and during normal pregnancy, 110 healthy women of mean age 25 years old and 53 healthy pregnant females of mean age 24.5 years old, who no one suffered from any autoimmune disease, were studied. In all women the anticardiolipin antibodies were measured in duplicate by the Enzyme Linked Immunosorbent Assay (ELISA). There was no difference in the percentage of the positive anticardiolipin antibodies between non pregnant and pregnant healthy women (9.1% and 5.6% respectively). Also, there was no difference in the antibodies levels during normal pregnancy, as well as, during an equal time of observation in non pregnant women. The positive anticardiolipin antibodies levels were low. Received: December 1997 / Accepted: 14 July 1999     

Inflammatory chemokine expression in the peripheral blood of neonates with perinatal asphyxia and perinatal or nosocomial infections

AIM: The inflammatory response induced by perinatal infections and asphyxia is considered to participate in neonatal brain damage. Inflammatory responses are characterized by the expression of chemokines. Although chemokine levels have been investigated in healthy newborns, their role during neonatal pathological conditions has not been studied. The aim of our study was to examine chemokine serum levels in asphyxiated and infected neonates. METHODS: Peripheral blood samples were obtained from perinatally asphyxiated and infected neonates during the first days of life and from neonates who developed nosocomial infections. Serum levels of interleukin-8 (IL-8), interferon-gamma-inducible protein-10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), macrophage inflammatory protein-1alpha (MIP-1alpha), and regulated upon activation, normal T cells expressed and secreted (RANTES) were determined. RESULTS: In perinatally asphyxiated neonates, IL-8 levels were significantly elevated on the 1st day of life. In perinatally infected neonates, IL-8 and IP-10 levels were significantly increased on the 1st day of life, while RANTES levels were significantly lower and remained so until the 4th day. In nosocomially infected neonates, IL-8, IP-10 and MIP-1alpha levels were significantly increased on diagnosis of infection. CONCLUSION: The neonatal immune system is able to produce chemokines for the induction of an inflammatory response during perinatal asphyxia and perinatal or nosocomial infections. Blockade of inflammatory chemokines could possibly contribute to the prevention of brain damage.     

Retinal complications of phakic intraocular lenses

High myopia has always been a challenge for refractive correction. Current laser surgical techniques, however, fall short of correcting high refractive errors due to lack of predictability, regression, corneal ectasia, and introduction of high order optical aberration. Phakic intraocular lenses (IOL) have been proposed as an effective refractive surgical procedure for the correction of severe myopia, but, despite recent advances in implant material technology and design, their concept is still under clinical investigation. Most of the concern regarding the complications of phakic IOLs focuses on the anterior segment of the eye. This review examines the posterior segment complications associated with phakic IOL implantation, evaluates possible pathogenetic mechanisms and discusses posterior segment complications, prevention and management.