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Cells maintain physicochemical characteristics of membranes in order to allow for proper function of membrane-associated cellular processes, such as endocytosis and exocytosis. To investigate the interplay between membrane properties and biological processes, we applied lipid engineering approaches that allowed for systematic manipulation of fatty acid unsaturation and sterol biosynthesis, the main regulators of membrane fluidity. In combination with electrophysiological membrane capacitance measurements, we were able to study the dependence of the endo- and exocytic activity of Saccharomyces cerevisiae on membrane lipid composition in vivo. We found that a strong decrease in the cell's total ergosterol content leads to a severely reduced frequency of vesicle fission (endocytosis), whereas the exocytic activity remained largely unaffected. In contrast, increased lipid saturation lowered both endocytic and the exocytic activity, with the former being more severely affected. We were able to correlate the decreased ratio of endocytic/exocytic frequencies (f endo /f exo ) upon lipid perturbation with the growth of yeast protoplasts, which is based on a surface enlargement resulting from a net excess of exocytic over endocytic flux. Experiments using clathrin-deficient mutants confirm a correlation between reduced endocytic activity and increased size of intact walled cells, as well as accelerated protoplast growth. These data show that lipid composition is intimately tied to membrane trafficking in yeast cells and suggest that endocytosis is particularly dependent on the lipid-defined properties of cell membrane., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Measurements of the membrane capacitance on animal cells has provided an excellent technique for monitoring of exo- and endocytotic activity in intact living cells. Here we review recent data in which the same technique was applied to plant cells and cells of the budding yeast Saccharomyces cerevisiae. The data show that unitary exo- and endocytotic events can also be measured with the same technique after removing the cell wall from these cells. The resulting protoplasts execute the same type of transient and permanent fusion/fission that is known from animal cells. Also the size of the vesicles, which are fusing or budding, are of the same order of magnitude as those recorded in animal cells. Together these data support the view of an evolutionary conserved mechanism for unitary exo- and endocytosis events in eukaryotes. The successful recordings of exo- and endocytotic activity in Saccharomyces cerevisiae by capacitance measurements now pave the way for correlating the abundant information on the molecular machinery of exo- and endocytosis in this model organism with distinct functional properties., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Fusion of exocytotic vesicles with the plasma membrane gives rise to an increase in membrane surface area, whereas the surface area is decreased when vesicles are internalized during endocytosis. Changes in membrane surface area, resulting from fusion and fission of membrane vesicles, can be followed by monitoring the corresponding proportional changes in membrane capacitance. Using the cell-attached configuration of the patch-clamp techniques we were able to resolve the elementary processes of endo- and exocytosis in yeast protoplasts at high temporal and spatial resolution. Spontaneous capacitance changes were predominantly in the range of 0.2-1 fF which translates to vesicle diameters of 90-200 nm. The size distribution revealed that endocytotic vesicles with a median at about 132 nm were smaller than exocytotic vesicles with a median at 155 nm. In energized and metabolizing protoplasts, endo- and exocytotic events occurred at frequencies of 1.6 and 2.7 events per minute, respectively. Even though these numbers appear very low, they are in good agreement with the observed growth rate of yeast cells and protoplasts., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: To assess the need of /P system use in soft cataract, Methods: prospective study--40 eyes with soft cataract (+/++); surgery with Infinity system, Ozil handpiece; in 20 eyes we used low levels (max 70%) of torsional ultrasound power and IP system; in 20 eyes we used higher levels of torsional ultrasound power without IP system; we assessed: the CME value and the presence of cornela edema., Results: In cases with tosional ultrasound only: average value of CME--2.4; maxim value of CME--4.3; all corneas without edema. In cases with torsional ultrasound and IP system; average value of CME--3.6; maxim value of CME--7.2; 4 eyes with decemetic folds in central cornea., Conclusions: In soft cataracts is better to not use IP system

Purpose: To assess the efficacy and safety of intravitreal triamcinolone acetonide in diabetic macular oedema., Methods: prospective study; 76 patients, 102 eyes; preoperative assessment: visual acuity, intraocular pressure, fundus biomicroscopy fluoresceine angiography, sometimes OCT; postoperative assessment: visual acuity, intraocular pressure, fundus biomicroscopy, fluoresceine angiography, sometimes OCT., Results: Visual acuity improvement in 42% cases; subjective improvement of visual acuity in 72% of cases, Conclusions: Triamcinolon acetonide may play a role in treatment of diabetic macular oedema.

We show a clinical case of siderosis bulbi with absolute secondary glaucoma. The initial diagnosis was primary open angle glaucoma in both eyes, and the patient was treated with eye drops for 4 years. After reassessment of anamnesis, clinical and paraclinical investigations we find that one eye is normal and the real diagnosis in the involved eye.

"Red eye" is a sign and the same time a symptom frequently met in the ophthalmological practice. The "red eye" is not always the clinical manifestation of a common conjunctivitis. We will present a case report of a patient who accused conjunctival hyperemia, lacrimation, foreign--body sensation; she was also describing recurrent conjunctivitis for the past year. After an detailed ophthalmologic examination and interdisciplinary consultations. She was diagnosed with Basedow Disease and paraselar meningioma with invasion in the pterigoid fossa. The authors are suggesting that there is an indirect left carotid - cavernous fistula.

Purpose: To clarify the diagnosis of open-angle glaucoma in an atypic case., Method: Assessment of intraocular pressure, the aspect of optic nerve head and automated perimetry show interpretable values. We assess the head of optic disc and the visual field in both mother and daughter of the patient., Results: The optic disc and the automated perimetry in both relatives was normal reassessment of visual field at the patient show a normal appearance., Conclusions: When the diagnosis of open-angle glaucoma is unclear, the assessment of members of family may be useful.

This paper highlights the case of a 46-year-old female patient who seeks ophthalmic medical advice for her complaint about double vision on right gaze. Patient's medical history reveals several symptoms like headaches, progressive hearing loss on right side and dysphonia for which all investigations proved irrelevant. Thourough clinical examination, lab exams and imaging techniques revealed the cause for this symptoms i.e. glomic tumour with middle ear extention. We find this case to be exceptional as ocular symptoms led to the diagnose of a non-ocular serious, possible life threatening condition, bearing in mind that previously occured non-ocular symptoms couldn't elucidate the cause.

Purpose: To reassess the diagnosis in a group of patients with diagnosis and treatment for open-angle glaucoma., Method: Group of 100 patients with diagnosis and treatment for open-angle glaucoma, sent in our clinic for automated perimetry. We assess: intraocular pressure, automated perimetry, the head of optic disc; sometimes we stopped the treatment and reassess the intraocular pressure; sometimes pahimetry. We confirm or not the diagnosis of open-angle glaucoma., Results: In 41 patients the diagnosis of open-angle glaucoma was not real., Conclusions: The diagnosis of open-angle glaucoma is made often without clear medical evidences.

The authors present the case of a patient with ocular pain and visual impairment after an ocular trauma. The ophthalmologic exam and the complementary exams show atypical aspects of the traumatic ocular pathology.

Purpose: To assess the efficacy of amniotic membrane transplantation for the improvement of symptoms in bullous keratopathy., Material and Method: Prospective study. 14 patients were operated between 01.02.2003 - 01.02.2006. the follow-up period: between 6 and 42 months with an average of 18 months. The following parameters were evaluated: corneal re-epithelialisation appearance of epithelial bullae, pain, photophobia., Results: In 11 cases there was an improvement of the symptomatology: complete in 8 cases and partial in 3 cases., Conclusions: Amniotic membrane transplantation is an efficient palliative treatment for bullous keratopathy.

This case present the consequences of performing the cataract surgery on an eye with intraocular tumor, pointing the importance of a detailed and complete examination, even for the benign and easy to diagnostic diseases.

The paper's aim is to evidence the quantitative and qualitative modifications of the tear film before and after operation, in accordance with the presents of the pseudoexfoliative syndrome at the cataract operated patients.

The authors present the case of a patient having both toxic keratopathy and maculopathy after a medication with amiodarone. Some of the ocular damages are irreversible, even while amiodarone medication is stopped, which recommends the screening as an efficient tracking method for ocular reversible injuries, avoiding major loss of visual function.