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The famous Davies-GKSL secular Markovian master equation is tremendously successful in approximating the evolution of open quantum systems in terms of just a few parameters. However, the fully secular Davies-GKSL equation fails to accurately describe timescales short enough, i.e., comparable to the inverse of differences of frequencies present in the system of interest. A complementary approach that works well for short times but is not suitable after this short interval is known as the quasisecular master equation. Still, both approaches fail to have any faithful dynamics in the intermediate-time interval. Simultaneously, descriptions of dynamics that apply to the aforementioned "gray zone" often are computationally much more complex than master equations or are mathematically not well-structured. The filtered approximation (FA) to the refined weak-coupling limit has the simplistic spirit of the Davies-GKSL equation and allows capturing the dynamics in the intermediate-time regime. At the same time, our non-Markovian equation yields completely positive dynamics. We exemplify the performance of the FA equation in the cases of the spin-boson system and qutrit-boson system in which two distant timescales appear.

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If a quantum system interacts with the environment, then the Hamiltonian acquires a correction known as the Lamb-shift term. There are two other corrections to the Hamiltonian, related to the stationary state. Namely, the stationary state is to first approximation a Gibbs state with respect to original Hamiltonian. However, if we have finite coupling, then the true stationary state will be different, and regarding it as a Gibbs state to some effective Hamiltonian, one can extract a correction, which is called "steady-state" correction. Alternatively, one can take a static point of view, and consider the reduced state of total equilibrium state, i.e., system plus bath Gibbs state. The extracted Hamiltonian correction is called the "mean-force" correction. This paper presents several analytical results on second-order corrections (in coupling strength) of the three types mentioned above. Instead of the steady state, we focus on a state annihilated by the Liouvillian of the master equation, labeling it as the "quasi-steady state." Specifically, we derive a general formula for the mean-force correction as well as the quasi-steady state and Lamb-shift correction for a general class of master equations. Furthermore, specific formulas for corrections are obtained for the Davies, Bloch-Redfield, and cumulant equation (refined weak coupling). In particular, the cumulant equation serves as a case study of the Liouvillian, featuring a nontrivial fourth-order generator. This generator forms the basis for calculating the diagonal quasi-steady-state correction. We consider spin-boson model as an example, and in addition to using our formulas for corrections, we consider mean-force correction from reaction-coordinate approach.

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OBJECTIVE: In oral rehabilitation, a full mouth minimal invasive treatment can represent a major challenge for the patient and the dentist. The purpose of this article is to present a new technique to restore eroded teeth and recover the vertical dimension with a simple and predictable technique. CLINICAL CONSIDERATIONS: Occlusal tabletop restorations are a suitable conservative option to restore anatomy and vertical dimension augmentation but highly sensitive. The cementation of those restorations without stable landmarks, the cement excess removal, the insertion path, or the time needed are some of the difficulties can be faced. Now a days with the new CAD-CAM techniques is possible to develop a new occlusal tabletop manufacturing alternative utilizing 3D-printed technology by unifying the restorations with a customized connector that allows us to print several onlays at same time, as a single object, also being cemented at once. CONCLUSIONS: This protocol reduces the technique sensitivity of a vertical dimension oral rehabilitation process, reduce the chair time, enhancing the patient-comfort and delivers a unique way to restore dental lost anatomy as a definitive or temporary way with printing materials. CLINICAL SIGNIFICANCE: With the advent of new CAD-CAM 3D printing materials, which are increasingly versatile and gaining favor among clinicians, it is now possible to address complex clinical situations with greater predictability. This technology enables the development of treatment solutions that are both effective and efficient, consequently reducing clinical time for the patient.

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A clinical observation usually encountered after vestibuloplasty or interventions aiming at deepening the vestibule with or without simultaneous free epithelialized grafts in the posterior ridges is that they are subjected to major dimensional changes attributed to the buccinator fibers attachment. Hence, this study aimed at assessing the attachment of the buccinator muscles in relation to other anatomical landmarks. An ex-vivo study was performed in cadaver heads to explore the association of fibers attachment in relation to the distance from the crestal aspect of edentulous alveolar process (CAP) and the vestibular depth (VD), crestal band of keratinized mucosa (KM), and ridge height (RH). Interestingly, VD and KM were found to be strongly correlated. Likewise, VD/KM and CAP-BUC were further noted being correlated. CAP-BUC was negatively correlated with RH. Accordingly, the more atrophic the alveolar ridge (being more noticeable in the mandible) is, the shallower the vestibule, the lesser the crestal band of KM and the more crestal attachment of the buccinator muscular fibers. That might be the reason why whenever performing free epithelized graft in the posterior ridges to enhance the peri-implant soft tissue phenotype and deepening the vestibule, the graft is subjected to major dimensional changes.

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Objective: To quantify the volume of the follicular spaces of impacted lower third molars (ILTMs) with different impaction positions and angulations using cone-beam computed tomography (CBCT) and to determine its association with the histopathological findings. Study design: This study included 103 ILTMs of 33 men and 70 women aged 18-46 years (mean age, 29.18 years). The follicular space volumes were measured on CBCT by manual segmentation and correlated with the histopathological diagnosis of each ILTM having different impaction positions and angulations. Statistical Product and Service Solutions, version 24, was used for statistical analyses by applying the t-test and binary logistic regression and multiple linear regression tests (p < 0.05). Results: Overall, 83 (80.6%) dental follicles presented a non-pathological diagnosis (mean follicular volume, 0.10 cm3), whereas 20 (19.4%) presented a pathological diagnosis (mean follicular volume, 0.32 cm3; p = 0.001). Similarly, the impaction depth in Position C cases was associated with a pathological diagnosis (p = 0.010). Conclusion: The follicular volume of the ILTMs varied significantly in teeth with a histopathological diagnosis of a follicular cyst and was associated with the impaction depth, mainly in Position C cases, and its relationship with the mandibular ramus. A mean follicular volume of 0.32 cm3 was associated with a greater probability of a pathological diagnosis.

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INTRODUCTION: This article provides an overview of the potential use of ozone as an adjuvant during cancer treatment. METHODS: We summarize the findings of the most relevant publications focused on this goal, and we include our related clinical experience. RESULTS: Over several decades, prestigious journals have published in vitro studies on the capacity of ozone to induce direct damage on tumor cells and, as well, to enhance the effects of radiotherapy and chemotherapy. Indirect effects have been demonstrated in animal models: immune modulation by ozone alone and sensitizing effect of radiotherapy by concurrent ozone administration. The effects of ozone in modifying hemoglobin dissociation curve, 2,3-diphosphoglycerate levels, locoregional blood flow, and tumor hypoxia provide additional support for potential beneficial effects during cancer treatment. Unfortunately, only a few clinical studies are available. Finally, we describe some works and our experience supporting the potential role of local ozone therapy in treating delayed healing after tumor resection, to avoid delays in commencing radiotherapy and chemotherapy. CONCLUSIONS: In vitro and animal studies, as well as isolated clinical reports, suggest the potential role of ozone as an adjuvant during radiotherapy and/or chemotherapy. However, further research, such as randomized clinical trials, is required to demonstrate its potential usefulness as an adjuvant therapeutic tool.

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Enterovirus D68 was known to be the cause of mild to severe respiratory infections, but in the last few years, it has also been associated with myelitis and paralysis. This report describes the first Enterovirus D68 detections in acute flaccid paralysis cases occurring between December 2015 and March 2016 in Spain.

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Introduction. Persistent radiation-induced proctitis and rectal bleeding are debilitating complications with limited therapeutic options. We present our experience with ozone therapy in the management of such refractory rectal bleeding. Methods. Patients (n = 12) previously irradiated for prostate cancer with persistent or severe rectal bleeding without response to conventional treatment were enrolled to receive ozone therapy via rectal insufflations and/or topical application of ozonized-oil. Ten (83%) patients had Grade 3 or Grade 4 toxicity. Median follow-up after ozone therapy was 104 months (range: 52-119). Results. Following ozone therapy, the median grade of toxicity improved from 3 to 1 (p < 0.001) and the number of endoscopy treatments from 37 to 4 (p = 0.032). Hemoglobin levels changed from 11.1 (7-14) g/dL to 13 (10-15) g/dL, before and after ozone therapy, respectively (p = 0.008). Ozone therapy was well tolerated and no adverse effects were noted, except soft and temporary flatulence for some hours after each session. Conclusions. Ozone therapy was effective in radiation-induced rectal bleeding in prostate cancer patients without serious adverse events. It proved useful in the management of rectal bleeding and merits further evaluation.

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CONTEXT: Persistent or severe hemorrhagic radiation proctitis (HRP) has limited therapeutic options. OBJECTIVES: To describe our experience with ozone therapy (O3T) in the management of refractory HRP. METHODS: Patients (n=17; median age 69 years [range 42-80 years]) previously irradiated for prostate or uterine cancer and suffering persistent or severe HRP without response to conventional treatment were enrolled to receive an O3/O2 gas mixture via rectal insufflations and topical application of ozonized oil. Most of the patients (83%) had Grade 3 or Grade 4 toxicity. Median follow-up post-O3T was 40 months (range 3-56 months). RESULTS: Endoscopic treatments required were: 43 (median 1; range 0-10) pre-O3T; 17 (median 0; range 0-8; P=0.063) during O3T; and five (median 0; range 0-2; P=0.008) during follow-up. Hemoglobin levels were 10.35g/dL (7-14g/dL) pre-O3T and 13g/dL (9-15g/dL) (P=0.001) post-O3T. Median toxicity grades were 3 (range 2-4) pre-O3T, 1 (range 0-2; P<0.001) at the end of O3T, and 0 (range 0-1; P<0.001) at the last follow-up. CONCLUSION: Persistent advanced HRP was significantly improved with O3T. The addition of O3T can be useful as a complementary treatment in the long-term management of HRP and, as such, merits further evaluation.

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BACKGROUND: Headache afflicts approximately 10%-15% of the general population. Mixed results are obtained from various therapies, usually drugs, but also oxygen inhalation, behavioral psychology, physical therapy, and peripheral or central neurostimulation. When refractory to treatment, it has severe impact on quality of life. OBJECTIVES/SUBJECTS: Five (5) patients are presented who had suffered from severe/persistent headache refractory to standard management (including 5-HT1 agonist triptan drugs) and were treated with ozone therapy. INTERVENTIONS: Ozone administration was by major autohemotherapy. The procedure involved venous blood drawn into a sterile single-use glass bottle containing anticoagulant, gently mixed with an equal volume of O3/O2 gas mixture (prefiltered through a sterile 0.20-µm filter) and slowly reinfused back into the donor patient via the antecubital vein. OUTCOME MEASURES: The analyzed parameters were analgesia requirements, days of sick leave due to headache, number of headache events, and pain intensity according to the visual analogue scale (VAS); these recorded at three time points: pre-ozone therapy, post-ozone therapy, and before the last follow-up (mean: 64.6±36.8 months). RESULTS: The number of headache episodes pretreatment (n=80; range 5-200) was significantly decreased during the first 6 months post-treatment (n=0, range 0-1; p=0.042) and over the 6 months before the last follow-up visit (n=1, range 0-2; p=0.043). The corresponding VAS scores were 8.7±0.8 pretreatment versus 1.1±2.5 the 6 months post-treatment (p=0.003) and versus 3.1±3.3 the 6 months before last follow-up visit (p=0.036). CONCLUSIONS: Ozone therapy decreased headache episodes and pain severity over a protracted period. This novel approach is effective and merits further research.

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BACKGROUND: Radiation-induced brain injury (RBI) and low-perfusion brain syndromes are mediated by ischemia and hypometabolism and have limited treatment options. Ozone therapy as treatment in vascular diseases has been described, but the effects on brain tissue have not been well documented. CASE REPORT: We describe a 75-year-old patient with vascular risk factors and meningioma who was treated with stereotactic radiosurgery. 14 months later the patient presented with progressive clinical impairment despite the use of acetylsalicylic acid and corticosteroids. Clinical and imaging evaluations before/after ozone therapy were done by magnetic resonance imaging (MRI), computed tomography (CT), single photon emission computed tomography (SPECT), and positron emission tomography (PET); performance status assessment was done using Barthel Index and World Health Organization/Eastern Cooperative Oncology Group Scale (WHO/ECOG Scale). Ozone therapy was performed by autohemotransfusion. RESULTS: Basal images showed brain areas with ischemia and hypometabolism compatible with ischemic processes and/or RBI. There were no changes in MRI or CT scan images following ozone therapy. However, improvements in brain perfusion and metabolism were demonstrable with SPECT and PET; they correlated with clinical development and performance status scales. CONCLUSION: This report supports our previous works about the effect of ozone therapy in cerebral blood flow, and it suggests the use of ozone therapy in ischemic and hypometabolic brain syndromes such as stroke or RBI.

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BACKGROUND: Progressive radiation-induced cystitis can become a serious clinical problem the therapeutic solution of which is limited and almost invariably aggressive. Ozone therapy is a nonconventional therapy that has been reported to offer benefits in late-onset wound healing and ischemic disorders. This report describes a patient with progressive radiation-induced hematuria from standard conservative treatment that was further treated with ozone therapy. METHOD: Ozone therapy was achieved by intravesical instillation of ozonized bi-distilled water over a period of 30 minutes, three sessions per week during the first weeks. Later, ozone therapy sessions were decreased and involved ozonized water or direct intravesicular instillation of ozone at 20-25 microg/mL. RESULTS: Hematuria was successfully controlled by intravesical application of ozone therapy. CONCLUSIONS: The successes achieved with this technique suggest that intravesicular instillation of ozonized bi-distilled water or ozone merits further investigation with a view to its application to counter this radiation-induced side-effect.

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Tumor hypoxia is an adverse factor for chemotherapy and radiotherapy. Ozone therapy is a non-conventional form of medicine that has been used successfully in the treatment of ischemic disorders. This prospective study was designed to assess the effect of ozone therapy on tumor oxygenation. Eighteen subjects were recruited for the study. Systemic ozone therapy was administered by autohemotransfusion on three alternate days over one week. Tumor oxygenation levels were measured using polarographic needle probes before and after the first and the third ozone therapy session. Overall, no statistically significant change was observed in the tumor oxygenation in the 18 patients. However, a significant decrease was observed in hypoxic values

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Advanced head and neck (H&N) tumors have a poor prognosis, and this is worsened by the occurrence of hypoxia and ischemia in the tumors. Ozonetherapy has proved useful in the treatment of ischemic syndromes, and several studies have described a potential increase of oxygenation in tissues and tumors. The aim of this prospective study was to evaluate the clinical effect of ozonetherapy in patients with advanced H&N cancer in the course of their scheduled radiotherapy. Over a period of 3 years, 19 patients with advanced H&N tumors who were undergoing treatment in our department with non-standard fractionated radiotherapy plus oral tegafur. A group of 12 patients was additionally treated with intravenous chemotherapy before and/or during radiotherapy. In the other group of seven patients, systemic ozonetherapy was administered twice weekly during radiotherapy. The ozonetherapy group was older (64 versus 54 years old, P = 0.006), with a higher percentage of lymph node involvement (71% versus 8%, P = 0.019) and with a trend to more unfavorable tumor stage (57% versus 8% IVb + IVc stages, P = 0.073). However, there was no significant difference in overall survival between the chemotherapy (median 6 months) and ozonetherapy (8 months) groups. Although these results have to be viewed with caution because of the limited number of patients, they suggest that ozonetherapy could have had some positive effect during the treatment of our patients with advanced H&N tumors. The adjuvant administration of ozonetherapy during the chemo-radiotherapy for these tumors merits further research.

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BACKGROUND AND OBJECTIVE: Ozone therapy is being used to treat ischemic disorders. However, the underlying mechanisms for the success are unknown and the therapy has not been accepted fully within conventional medicine. This study sought to assess the effect of ozone therapy on resting muscle oxygenation. PATIENTS AND DESIGN: Twenty-three (23) patients and 3 volunteers were recruited for this prospective study. Systemic ozone therapy was administered by autohemotransfusion on three alternate days over 1 week. Tissue oxygenation (mmHg) was directly measured in the tibialis anterior muscle using polarographic needle electrodes before and after the first and the third ozone therapy session. RESULTS: Globally, the differences in oxygenation were not statistically significant but there was a significant decrease in the percentage of low-oxygenated values (pO(2) < 5 mmHg) following ozone sessions (p < 0.02). The change in muscle oxygenation following ozone therapy was inversely correlated with age (r = -0.398; p = 0.044) and with the initial (baseline pretherapy) muscle oxygenation values (r = -0.644; p < 0.001), indicating that the more poorly oxygenated muscles benefited most from the therapy. A significant (p = 0.031) higher oxygenation in these tissues was observed 48 hours after the second session. CONCLUSIONS: Ozone therapy can modify oxygenation in resting muscles, particularly of those that are most hypoxic. Our results suggest that ozone therapy could be used effectively as a complementary treatment of hypoxic and ischemic syndromes and that the therapy warrants further investigation for possible application in other clinical conditions.

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Haemoglobin concentrations and tumour-pO(2) were evaluated pre-therapy in 30 patients with head and neck cancers. Anterior tibialis muscle-pO(2) was additionally measured in 16 of these patients. Tumour-pO(2) was lower in the most anaemic patients (P=0.032) and correlated with muscle-pO(2) (r=0.809, P<0.001). These results suggest that haemoglobin concentration influences tumour-oxygenation.

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