Choroidal Structure after Half-Dose Photodynamic Therapy in Chronic Central Serous Chorioretinopathy

The study aims to analyze the changes produced by half-dose photodynamic therapy (HD-PDT) in the choroid of eyes with chronic central serous chorioretinopathy (CSC) applying the binarization method to spectral domain optical coherence tomography (SDOCT) and OCT Angiography (OCTA) images. SDOCT and OCTA were performed before, one hour, one week, and one month after HD-PDT. Binarization with a modified Niblack method and analysis by ImageJ were applied. An average ratio between luminal part and total structure was calculated. Twenty-two eyes of 21 patients (20 male and 1 female; mean age 54.8 years) were enrolled. A statistically significant reduction of the central choroidal thickness was observed one week (from 407 µm to 362 µm, p = 0.034) and one month (from 407 µm to 341.5 µm, p = 0.0004) after HD-PDT. The baseline average ratio between luminal part and total structure was 33.4% in SDOCT, and 61.1% in OCTA. These values were 35.3% and 61% one hour, 33.9% and 60.4% one week, and 34.5% and 60.6% one month after HD-PDT, respectively. Overall, PDT seems to produce short-term changes on the luminal component of both choriocapillaris and choroid, which return to baseline status after one month from treatment. However, choroid stays significantly thinner after one month, with both luminal and interstitial components significantly reduced

Luigi Galvani and animal electricity: two centuries after the foundation of electrophysiology

Luigi Galvani and his famous experiments on frogs carried out in the second half of the 18th century belong more to legend than to the history of science. Galvani not only laid the foundations of a new science, electrophysiology, but also opened the way for the invention of the electric battery, and thus for the development of the physical investigations of electricity. However, in spite of the widespread celebration of his work, Galvani's scientific endeavours have been largely misrepresented in the history of science. The scholar of Bologna has a stereotyped image as an 'occasional' scientist, who started his studies by chance, largely ignored the scientific theories of his time and wandered aimlessly in mental elaborations until the physicist of Pavia, Alessandro Volta, entered the field, correctly interpreted Galvani's results and eventually developed the electric battery. With the present understanding of electrical phenomena in excitable membranes, it is now time to reconsider the real matter raised by Galvani's discoveries and by his hypothesis of an intrinsic 'animal electricity', and to make a clearer evaluation of a revolutionary phase of scientific progress

Synaptic transmission between photoreceptors and horizontal cells in the turtle retina

Low calcium, high magnesium, and cobalt hyperpolarize the horizontal cell membrane and suppress the response to light, but only partially affect the response of receptor cells. These observations are consistent with the interpretation that a depolarizing transmitter is released by photoreceptors in darkness. The hyperpolarizing response to light of the horizontal cells would then result from a reduction in the amount of transmitter released

Galileo's Visions

The central aim of this book is to analyse the scientific and philosophical work of Galileo Galilei from the particular viewpoint of his approach to the senses (and especially vision) as a way for acquiring trustworthy knowledge about the constitution of the world. For Galileo the senses are potentially ambiguous. Accordingly, reliable information capable of penetrating the complexity of reality can only be obtained by interpreting the sensory data critically. The philosophical background of Galileo’s attitude to the senses is his awareness that nature has not developed a specific language aimed at communicating with senses generally and human senses in particular. The culture of his age was based mainly on a mechanist approach to the world. In this context, Galileo’s analysis of the senses corresponds closely to a fundamental tenet of modern sensory physiology and psychophysics—the absence in the world of specific sensory signals like sounds, colours, tastes, and odours

Shocking frogs. Galvani, Volta, and the electric origins of neuroscience

This book provides an accurate and detailed reconstruction of the research pathway that led the Bologna physician, Luigi Galvani, to discover the electric nature of nerve conduction and muscle excitation more than two centuries ago. It is based on a thorough analysis of many (often unpublished) historical sources, and an investigation of the cultural and scientific context in which Galvani's' endeavours flourished. The book highlights another important episode in eighteenth century research – the invention of the electric battery by Alessandro Volta. For the first time, the stories of Galvani and his frogs and Volta and his battery are presented free from the stereotypes that have accumulated over the intervening years. This is achieved on the basis of an approach that combines an in-depth historical approach with a profound awareness of the scientific problems involved. This book will enable neuroscientists, physiologists, biophysicists, and biologists the opportunity of becoming aware of the detailed historical foundations of their science, and for historians and humanists to be informed of the intellectual and human dimensions of science at the onset of a revolution in the history of the life sciences

Helmholtz / Dal Secolo dei Lumi alle Neuroscienze

Relativamente poco noto al pubblico italiano, Hermann von Helmholtz (1821-1894) è una figura di primo piano della scienza ottocentesca, non solo per l’importanza specifica dei risultati da lui ottenuti in fisica, medicina, fisiologia e teoria musicale, ma anche e soprattutto perché la sua prodigiosa attività si situa in una fase storica decisiva per l’emergere del modo moderno di fare scienza, vale a dire nel momento in cui l’approccio conoscitivo alla realtà naturale passa dalla fiducia illuministica nella ragione alle inquietudini della filosofia romantica della natura. Con un linguaggio brillante e accessibile anche al vasto pubblico, Meulders rievoca qui in tutta la loro portata e complessità l’opera scientifica e l’itinerario intellettuale di Helmholtz, disegnando il profilo di un esponente di quella grande cultura europea (senza distinzioni di campi) a cui gli studiosi moderni devono volgere lo sguardo se vogliono recuperare un armonico rapporto tra i due «saperi» – scientifico e umanistico –, necessario per far fronte alle sfide della modernità