Neurotrophic keratitis (NK) is a degenerative disease characterized by corneal sensitivity reduction, spontaneous epithelium breakdown, and impairment of corneal healing. Several causes of NK, ...including herpetic keratitis, diabetes, and ophthalmic and neurosurgical procedures, share the common mechanism of trigeminal damage. Diagnosis of NK requires accurate investigation of clinical ocular and systemic history, complete eye examination, and assessment of corneal sensitivity. All diagnostic procedures to achieve correct diagnosis and classification of NK, including additional examinations such as in vivo confocal microscopy, are reviewed. NK can be classified according to severity of corneal damage, ie, epithelial alterations (stage 1), persistent epithelial defect (stage 2), and corneal ulcer (stage 3). Management of NK should be based on clinical severity, and aimed at promoting corneal healing and preventing progression of the disease to stromal melting and perforation. Concomitant ocular diseases, such as exposure keratitis, dry eye, and limbal stem cell deficiency, negatively influence the outcome of NK and should be treated. Currently, no specific medical treatment exists, and surgical approaches, such as amniotic membrane transplantation and conjunctival flap, are effective in preserving eye integrity, without ameliorating corneal sensitivity or visual function. This review describes experimental and clinical reports showing several novel and potential therapies for NK, including growth factors and metalloprotease inhibitors, as well as three ongoing Phase II clinical trials.
Tinea versicolor is a common noninvasive cutaneous fungal disease. We recount a case of tinea versicolor that mimicked type I (classic adult) pityriasis rubra pilaris. A 54-year-old white man ...reported a 20-year history of a recurrent pruritic eruption that had marginally improved with use of selenium sulfide shampoo and treatment with oral antihistamines. Results of a skin examination revealed erythematous plaques; islands of spared skin; and follicular erythematous keratotic papules on the trunk, shoulders, and upper arms. A lesion was scraped to obtain skin scales for potassium hydroxide staining. Examination of the stained samples revealed the characteristic "spaghetti and meatballs," confirming the diagnosis.
We study decoherence effects on mixing among three generations of neutrinos. We show that in presence of a non-diagonal dissipation matrix, both Dirac and Majorana neutrinos can violate the
CPT
...symmetry and the oscillation formulae depend on the parametrization of the mixing matrix. We reveal the
CP
violation in the transitions preserving the flavor, for a certain form of the dissipator. In particular, for such dissipators, the
CP
violation affects all the transitions in the case of Majorana neutrinos, unlike Dirac neutrinos which still preserve the
CP
symmetry in one of the transitions flavor preserving. The precise form of the dissipation matrix is not known a-priori as it depends on the nature of the phenomenon that originates it. However, our theoretical results show that decoherence effects, if exist for neutrinos, could allow to reveal the neutrino nature and to test fundamental symmetries.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We analyze many aspects of the phenomenon of the decoherence for neutrinos propagating in long baseline experiments. We show that, in the presence of an off-diagonal term in the dissipative matrix, ...the Majorana neutrino can violate the CPT symmetry, which, on the contrary, is preserved for Dirac neutrinos. We show that oscillation formulas for Majorana neutrinos depend on the choice of the mixing matrix U. Indeed, different choices of U lead to different oscillation formulas. Moreover, we study the possibility to reveal the differences between Dirac and Majorana neutrinos in the oscillations. We use the present values of the experimental parameters in order to relate our theoretical proposal with experiments.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The subcutaneous implantable cardioverter-defibrillator (S-ICD) is a potential alternative to transvenous systems in hypertrophic cardiomyopathy (HCM) where lead complications are a significant ...issue.
To compare the S-ICD efficacy of defibrillation threshold (DFT) testing, arrhythmia therapy, and complications in HCM versus non-HCM patients.
Outcomes of patients with HCM implanted with S-ICD were compared to non-HCM S-ICD recipients using pooled data from a total of 872 subjects enrolled in the EFFORTLESS Registry and US IDE study.
The cohort included 99 HCM (75% male) and 773 non-HCM (72% male) patients with a median follow-up of 637 days. The HCM cohort was younger and more likely to receive a primary-prevention S-ICD (88.5% vs 67.5%, P < .0001). During implant testing, successful defibrillation at ≤80 J was achieved in 98.9% of HCM and 98.5% of non-HCM patients. One year postoperative complication-free rates were similar: 92.7% in HCM (with no lead complications) versus 89.5% in non-HCM. There were 3 appropriate shocks for ventricular tachycardia in 3 HCM patients that were all converted by the first shock. Overall final shock conversion efficacy was 100% in HCM versus 98% in non-HCM (P = ns). Inappropriate shocks occurred in 12.5% of HCM patients and 10.3% of non-HCM patients (P = ns), being reduced by 47% using dual-zone programming.
These initial data indicate the S-ICD is safe and effective in patients with HCM who are at high risk of ventricular arrhythmias and pass preimplantation electrocardiogram screening. Inappropriate shocks were mainly due to T-wave oversensing, but there were no lead complications requiring reintervention.
Two principal mechanisms are thought to be responsible for Brugada syndrome (BS): (1) right ventricular (RV) conduction delay and (2) RV subepicardial action potential shortening. This in vivo ...high-density mapping study evaluated the conduction and repolarization properties of the RV in BS subjects.
A noncontact mapping array was positioned in the RV of 18 BS patients and 20 controls. Using a standard S(1)-S(2) protocol, restitution curves of local activation time and activation recovery interval were constructed to determine local maximal restitution slopes. Significant regional conduction delays in the anterolateral free wall of the RV outflow tract of BS patients were identified. The mean increase in delay was 3-fold greater in this region than in control (P=0<0.001). Local activation gradient was also maximally reduced in this area: 0.33+/-0.1 (mean+/-SD) mm/ms in BS patients versus 0.51+/-0.15 mm/ms in controls (P<0.0005). The uniformity of wavefront propagation as measured by the square of the correlation coefficient, r(2), was greater in BS patients versus controls (0.94+/-0.04 versus 0.89+/-0.09 mean+/-SD; P<0.05). The odds ratio of BS hearts having any RV segment with maximal restitution slope >1 was 3.86 versus controls. Five episodes of provoked ventricular tachycardia arose from wave breaks originating from RV outflow tract slow-conduction zones in 5 BS patients.
Marked regional endocardial conduction delay and heterogeneities in repolarization exist in BS. Wave break in areas of maximal conduction delay appears to be critical in the initiation and maintenance of ventricular tachycardia. These data indicate that further studies of mapping BS to identify slow-conduction zones should be considered to determine their role in spontaneous ventricular arrhythmias.
The study of the decay of an accelerated proton recently provided a “theoretical proof” of the Unruh effect. On the basis of general covariance of Quantum Field Theory, indeed, it was found that the ...decay rates in the inertial and comoving frames do coincide only when the thermal nature of the accelerated vacuum is taken into account. Such an analysis was then extended to the case with mixed neutrinos. In this paper, we show that, by further embedding neutrino oscillations in the above framework, the requirement of general covariance necessarily entails the use of flavor neutrinos as asymptotic states, as well as the occurrence of neutrino oscillations in the Unruh thermal bath.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Mixing transformations for a uniformly accelerated observer (Rindler observer) are analyzed within the quantum field theory framework as a basis for investigating gravitational effects on flavor ...oscillations. In particular, the case of two charged boson fields with different masses is discussed. In spite of such a minimal setting, the standard Unruh radiation is found to lose its characteristic thermal interpretation due to the interplay between the Bogoliubov transformation hiding in field mixing and the one arising from the Rindler spacetime structure. The modified spectrum detected by the Rindler observer is explicitly calculated in the limit of the small mass difference.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
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