Digital holographic microscopy for the evaluation of human sperm structure.

The morphology of the sperm head has often been correlated with the outcome of in vitro fertilization, and has been shown to be the sole parameter in semen of value in predicting the success of intracytoplasmic sperm injection and intracytoplasmic morphologically selected sperm injection. In this paper, we have studied whether digital holographic microscopy (DHM) may be useful to obtain quantitative data on human sperm head structure and compared this technique with high-power digitally enhanced Nomarski optics. The main advantage of digital holography is that high-resolution three-dimensional quantitative sample imaging may be automatically produced by numerical refocusing of a two-dimensional image at different object planes without any mechanical scanning. We show that DHM generates useful information on the dimensions and structure of human sperm, not revealed by conventional phase-contrast microscopy, in particular the volume of vacuoles, and suggest its use as an additional prognostic tool in assisted reproduction technology.

Identification of bovine sperm head for morphometry analysis in quantitative phase-contrast holographic microscopy.

An investigation is reported of the identification and measurement of region of interest (ROI) in quantitative phase-contrast maps of biological cells by digital holographic microscopy. In particular, two different methods have been developed for in vitro bull sperm head morphometry analysis. We show that semen analysis can be accomplished by means of the proposed techniques . Extraction and measurement of various parameters are performed. It is demonstrated that both proposed methods are efficient to skim the data set in a preselective analysis for discarding anomalous data.

Digital self-referencing quantitative phase microscopy by wavefront folding in holographic image reconstruction.

A completely numerical method, named digital self-referencing holography, is described to easily accomplish a quantitative phase microscopy for microfluidic devices by a digital holographic microscope. The approach works through an appropriate numerical manipulation of the retrieved complex wavefront. The self-referencing is obtained by folding the retrieved wavefront in the image plane. The folding operation allows us to obtain the correct phase map by subtracting from the complex region of interest a flat area outside the microfluidic channel. To demonstrate the effectiveness of the method, quantitative phase maps of bovine spermatozoa and in vitro cells are retrieved.

Autophagy regulates hepatocyte identity and epithelial-to-mesenchymal and mesenchymal-to-epithelial transitions promoting Snail degradation.

Epithelial-to-mesenchymal transition (EMT) and the reverse process mesenchymal-to-epithelial transition (MET) are events involved in development, wound healing and stem cell behaviour and contribute pathologically to cancer progression. The identification of the molecular mechanisms underlying these phenotypic conversions in hepatocytes are fundamental to design specific therapeutic strategies aimed at optimising liver repair. The role of autophagy in EMT/MET processes of hepatocytes was investigated in liver-specific autophagy-deficient mice (Alb-Cre;ATG7(fl/fl)) and using the nontumorigenic immortalised hepatocytes cell line MMH. Autophagy deficiency in vivo reduces epithelial markers' expression and increases the levels of mesenchymal markers. These alterations are associated with an increased protein level of the EMT master regulator Snail, without transcriptional induction. Interestingly, we found that autophagy degrades Snail in a p62/SQSTM1 (Sequestosome-1)-dependent manner. Moreover, accordingly to a pro-epithelial function, we observed that autophagy stimulation strongly affects EMT progression, whereas it is necessary for MET. Finally, we found that the EMT induced by TGFß affects the autophagy flux, indicating that these processes regulate each other. Overall, we found that autophagy regulates the phenotype plasticity of hepatocytes promoting their epithelial identity through the inhibition of the mesenchymal programme.

Tissue expansion in the treatment of pressure ulcers.

The authors report their experience using skin expanders in 11 patients with severe bed sores. The expanders, with different volumes, from 250 to 1000 cc, were generally overfilled using the cutaneous tonometer. In fact, with the information revealed by this apparatus on the skin in expansion, the authors were able to reduce the filling intervals without risking ulceration. In their experience, the results obtained were satisfactory: All patients treated achieved surgical recovery. The authors see a wide future for skin-expander use in pressure-ulcer treatment. They have a working hypothesis about using expanders to progressively advance sensitive skin in areas subject to ulceration. This hypothesis is based on the possibility of reexpanding the same flap several times, as has been seen in the treatment of other types of pathology.

Multiple CT imaging in pressure sores.

In patients affected by pressure sores, bones can be reached easily by the infection. This suggested a new way for a more precise diagnostic evaluation, looking at the most recent technological knowledge, which can offer a better evaluation of single lesions for a better planning of surgical operations. The possibility of performing multiple imaging under a CT guide, as well as a simple technique for contrast permanence within the sore, led the authors to demonstrate the validity of modern CT scanning as a main diagnostic method.

[Importance of cleansing in the topical treatment of skin lesions. A parallel study carried out in 20 patients and 30 rats]. / Importanza della detersione nel trattamento topico delle lesioni cutanee. Studio parallelo condotto su 20 pazienti e su 30 ratti.

There are frequent reports of the chronic nature of skin ulcers of varying etiology (burns, bedsores, wound diastasis, etc.); these heal with considerable difficulty probably due to problems related to the excessive use of disinfectants which, in spite of having a good bacterial action, interfere with re-epithelialisation processes. The aim of this study was to assess the value of simple wound cleansing instead of disinfection in those cases where there are no manifest signs of bacterial contamination. A widely sold solution, Katoderm (Devergè, Turin), was used in this study. The study was performed in two stages; the first in laboratory animals and the second in patients with small persistent lesions. The results of the study carried out in rats showed a significant prolongation of healing time in the group treated with polyvinylpyrrolidone-iodine compared to those in which lesions were only cleansed with Katoderm. The results of the clinical study also highlighted the faster speed of healing in patients treated with cleansing alone.

Reconstruction of ischial pressure ulcers by skin expansion.

Ten patients, eight of whom were paraplegic, have had ischial pressure ulcers treated by skin expansion. Skin expanders 680 ml in size were inserted subcutaneously on the posterior aspect of the thigh. They were filled during a short period without complications, the filling being monitored with a cutaneous tonometer. At a second operation the ulcers were repaired easily with the expanded flaps. After a few weeks the patients were able to undergo a programme of rehabilitation that included sitting with the expanded flaps. No ulcers recurred during a median follow-up of 12 months (range 8-34).

Digital holography as a method for 3D imaging and estimating the biovolume of motile cells.

Sperm morphology is regarded as a significant prognostic factor for fertilization, as abnormal sperm structure is one of the most common factors in male infertility. Furthermore, obtaining accurate morphological information is an important issue with strong implications in zoo-technical industries, for example to perform sorting of species X from species Y. A challenging step forward would be the availability of a fast, high-throughput and label-free system for the measurement of physical parameters and visualization of the 3D shape of such biological specimens. Here we show a quantitative imaging approach to estimate simply and quickly the biovolume of sperm cells, combining the optical tweezers technique with digital holography, in a single and integrated set-up for a biotechnology assay process on the lab-on-a-chip scale. This approach can open the way for fast and high-throughput analysis in label-free microfluidic based "cytofluorimeters" and prognostic examination based on sperm morphology, thus allowing advancements in reproductive science.

Ambulant vacuum-assisted closure of skin-graft dressing in the lower limbs using a portable mini-VAC device.

A skin graft may fail to adhere to the recipient site because of fluid collecting between the graft and the area being treated. We have devised a simple procedure, consisting of a vacuum-sealed dressing, to fix skin grafts on the lower limbs. A fully portable, battery-operated aspirator continuously draws secretions through a vacuum-sealed dressing, preventing accumulation of fluid underneath the graft. Patients are not confined to bed, thus reducing nursing time. The procedure was applied successfully in seven out of nine patients treated for ulcers of the lower limbs.