133 research outputs found
Use of Bichat's buccal fat pad for the sealing of orosinusal communications. A presentation of 8 cases
No full textObjectives: To determine the efficacy of the pediculate flap with the buccal fat pad in the sealing of orosinusal communications, describe the surgical technique used, and report the main complications. Patients and method: A retrospective study was made of 8 patients seen in the Service of Oral Surgery of the University of Barcelona Dental Clinic (Spain) for the treatment of orosinusal communications between the years 2007 and 2009. In all cases a pediculate flap with the buccal fat pad was used to solve the problem. Results: All of the orosinusal communications were successfully resolved with this technique. The immediate postoperative complications were pain (37.5%), inflammation (37.5%), edema (32.5%), trismus (37.5%), halitosis (14.3%), suppuration (12.5%) and rhinorrhea (12.5%). Conclusions: The use of Bichat"s buccal fat pad is not regarded as the technique of choice for sealing small to medium sized orosinusal communications. However, in the case of large communications, it is a good option, and the results obtained are optimum
Inhibition of antigen-presenting cell function by alendronate in vitro,
No full textBisphosphonates are potent inhibitors of bone resorption in vivo and are emerging as important and widely used drugs for the treatment of a variety of abnormal bone resorptive processes. In the current study we investigated the in vitro effects of 4-amino-l-hydroxybutyylidene-l,l-bisphosphonat(aelendronate), a recently developed, ex- tremely potent bisphosphonate, on the immune functions of human peripheral blood mononuclear cells (PBMCs). PBMC proliferation induced by lectins, alloantigens, and a nominal antigen (tetanus toxoid) was inhibited in a dose-dependent manner by alendronate. Pretreatment of monocytes, but not T cells, with the compound at concentrations ranging from to M was inhibitory, indicating that alendronate acts selectively on antigen-presenting cells (APCs).Alendronate did not affect the viability of monocytes or T cells or the expression of cell surface molecules known to play critical roles in antigen presentation. Alendronate exhibited dose- dependent inhibition of the production of interleukin-1P (IL-lP), interleukin-6 (IL-6), and tumor necrosis factor-a (TNF-a) by activated monocytes. The inhibitory effect of M alendronate on PBMC proliferation was reversed by 10 U/ml recombinant rIL-ap, whereas other cytokines such as IL-6, TNF-a,and granulocyte-macrophage colony-stimulating factor (GM-CSF) had no effect. Thus, alendronate acts on monocytes to inhibit their antigen- presentinglaccessory cell functions through a mechanism that can be overcome by exogenous IL-1. The inhibitory effect of this agent on cytokine production may contribute to its inhibitory effect on bone resorption
Age-related impairment of human T lymphocytes' activation: specific differences between CD4+ and CD8+ subsets
No full textThe relevance of physiological immune aging is of great interest with respect to determining disorders with pathologic immune function in aging individuals. In recent years, the relevance of changes in peripheral lymphocytes in age-associated neurologic diseases has become more evident. Due to the lack of immunological studies, covering more than one event after mitogenic activation, we envisaged a new concept in the present study, aiming to investigate several events, starting from T cell receptor (TCR) ligation up to T cell proliferation. In addition, we addressed the question whether changes are present in the subsets (CD4, CD8) with aging. Phosphorylation of tyrosine residues declines with increasing age in CD4+ cells. Fewer levels of CD69 positive cells after 4 h mitogenic activation, altered expression of cytokines (IL2, IFN-gamma and TNF-alpha; 22 h) and lower proliferation (72 h) were determined in aging. Moreover, it could be shown that CD8+ lymphocytes react more effectively to mitogenic stimulation with reference to CD69 expression and proliferation in both age groups (60 years old). These data indicate that T cell activation, mediated by TCR engagement, is significantly impaired in aging and both subsets are affected. However, bypassing the TCR does not fully restore T cell function, indicating that there are more mechanisms involved than impaired signal transduction through TCR only. The results will be discussed in relation to their relevance in neurodegenerative and psychiatric disorders
Prolonged use of nomegestrol acetate and risk of intracranial meningioma: a population-based cohort studyResearch in context
No full textSummary: Background: Nomegestrol acetate (NOMAC) is a synthetic potent progestogen. This study aimed to assess the risk of intracranial meningioma associated with the prolonged use of NOMAC. Methods: Observational cohort study using SNDS data (France). Women included had ≥ one dispensing of NOMAC between 2007 and 2017 (no dispensing in 2006). Exposure was defined as a cumulative dose >150 mg NOMAC within six months after first dispensing. A control group of women (cumulative dose ≤150 mg) was assembled. The outcome was surgery (resection or decompression) or radiotherapy for one or more intracranial meningioma(s). Poisson models assessed the relative risk (RR) of meningioma. Findings: In total, 1,060,779 women were included in the cohort (535,115 in the exposed group and 525,664 in the control group). The incidence of meningioma in the two groups was 19.3 and 7.0 per 100,000 person-years, respectively (age-adjusted RRa = 2.9 [2.4–3.7]). The RRa for a cumulative dose of more than 6 g NOMAC was 12.0 [9.9–16.0]. In the event of treatment discontinuation for at least one year, the risk of meningioma was identical to that in the control group (RRa = 1.0 [0.8–1.3]). The location of meningiomas in the anterior and middle part of the skull base was more frequent with exposure to NOMAC. Interpretation: We observed a strong dose-dependent association between prolonged use of NOMAC and the risk of intracranial meningiomas. These results are comparable to those obtained for cyproterone acetate, although the magnitude of the risk is lower. It is now recommended to stop using NOMAC if a meningioma is diagnosed. Funding: The French National Health Insurance Fund (Cnam) and the French National Agency for Medicines and Health Products Safety (ANSM) via the Health Product Epidemiology Scientific Interest Group EPI-PHARE
A hydrogenated amorphous silicon detector for Space Weather applications
No full textThe characteristics of a hydrogenated amorphous silicon (a-Si:H) detector are presented here for monitoring in space solar flares and the evolution of strong to extreme energetic proton events. The importance and the feasibility to extend the proton measurements up to hundreds of MeV is evaluated. The a-Si:H presents an excellent radiation hardness and finds application in harsh radiation environments for medical purposes, for particle beam characterization and, as we propose here, for space weather science applications. The critical flux detection limits for X rays, electrons and protons are discussed
TCAD modelling of a-Si:H devices for particle detection applications
No full textHydrogenated amorphous silicon (a-Si:H) has been proposed as a suitable material for particle detection applications thanks to its property to be deposited over a large area and above a variety of different substrates, including flexible materials. Moreover, the low cost and intrinsic radiation tolerance made this material appealing in applications where high fluences are expected, e.g. in high energy physics experiments. In order to optimize the device geometry and to evaluate its electrical behaviour in different operating conditions, a suit-able Technology CAD (TCAD) design methodology can be applied. In this work, carried out in the framework of the HASPIDE INFN project, we propose an innovative approach to the study of charge transport within the material, using the state-of-the-art Synopsys Advanced TCAD Suite. Different custom mobility models have been devised and implemented within the code as external PMI (Physical Model Interfaces), starting from the Poole- Frenkel model and accounting for different dependencies on temperature and internal potential distribution, thus resulting in a new mobility model embedded within the code. Simple test structures, featuring p-i-n diodes have been simulated and compared to experimental data as a benchmark. The overall aim was to account for the effect of different biasing conditions (namely, different electrical potential and electric field distribution within the device) and operating conditions (e.g. temperature). This work fosters the use of commercially available TCAD suite such as Synopsys Sentaurus, largely diffused in the radiation detection scientific community, for the design and optimization of innovative a-Si:H devices for particle detection applications
Specific focus on the basal dura for improving Cushing’s disease surgery: a cohort study
No full textInternational audienceBackground and objectives: In Cushing's disease, the rate of endocrine remission after surgery reaches 80% in expert centers. However, due to the tumor's capacity to invade surrounding dural structures, hypercortisolism persists in 20% of patients or recurs in 15%. To improve the likelihood of remission, tumor resection can be extended to the dura in patients who show basal dura invasion. The objective was to evaluate the benefit of a surgical strategy based on a systematic focus on the basal dura.Methods: Endoscopic surgery was performed in 89 adult patients with no obvious cavernous invasion. The basal dura was systematically removed whenever a macroscopic invasion was suspected. Three groups were defined: (i) resected but noninvaded dura (n = 14); (ii) resected and invaded dura (n = 16); and (iii) nonresected dura (n = 59). The studied cohort was compared to a control personal series of Cushing's patients with no systematic focus on the basal dura.Results: The mean follow-up duration was 19.9 ± 9.4 months. Endocrine remission was achieved in 15/16 (94%) patients with invaded dura, 14/15 (93%) patients with resected noninvaded dura and 50/59 (85%) patients with nonresected dura. Anterior pituitary deficits and diabetes insipidus occurred in 3% and 9% of patients respectively. Compared to the control series, our remission rate was significantly higher (88% vs. 75%, P =.019).Conclusion Tumorectomy extended to the basal dura is a safe procedure that maximizes surgical resection. Despite dura invasion, endocrine remission is high when the dura is removed. A systematic focus on the basal dura can optimize endocrine outcomes
Combined Nasoseptal and Inferior Turbinate Flap for Reconstruction of Large Skull Base Defect After Expanded Endonasal Approach: Operative Technique
No full textInternational audienceBACKROUND:Increasing indications for endoscopic endonasal approaches have led neurosurgeons to develop new reconstruction techniques for larger skull base defects. Vascularized grafts have been a great adjunction to reduce the rate of cerebrospinal fluid leak and can also be used to cover exposed critical structures such as the internal carotid artery. The nasoseptal flap and the inferior or middle turbinate flap are thus widely used in endoscopic skull base surgery, but may be insufficient for very large defects.OBJECTIVE:To present a new mucosal flap used to cover large skull base defects in which the mucosa of the inferior turbinate, inferior meatus, nasal floor, and nasal septum is harvested in 1 piece keeping both vascular pedicles intact (inferior turbinate and septal arteries).METHODS:We describe a surgical technique to harvest a combined inferior turbinate-nasoseptal flap.RESULTS:Technical pearls and surgical pitfalls are described through 2 clinical cases in which the nasoseptal mucosa was partially damaged during a previous surgery, rendering the nasoseptal flap insufficient by itself. The flap is harvested thanks to 2 mucosal cuts: a first circular cut around the choanal arch and the junction between the hard and the soft palate, and a second one combining classical cuts of the nasoseptal flap and the inferior turbinate flap.CONCLUSION:The inferior turbinate-nasoseptal flap can be a useful alternative in patients whose septal mucosa was partially damaged and/or with very large postoperative skull base defects
Síndrome de Turner: aspectos clínicos e avaliação do tratamento da baixa estatura com hormônio de crescimento em um Serviço de Referência em Endocrinologia Pediátrica
No full textTrabalho de Conclusão de Curso - Universidade Federal de Santa Catarina. Curso de Medicina. Departamento de Pediatria
pi+-, K+-, p and anti-p production in Z0 ---> q anti-q, Z0 ---> b anti-b, Z0 ---> u anti-u, d anti-d, s anti-s
No full textThe DELPHI experiment at LEP uses Ring Imaging Cherenkov detectors for particle identification. The good understanding of the RICH detectors allows the identification of charged pions, kaons and p rotons, covering the full momentum range from \mbox{0.7\!<\!p\!<\! 45.6~\gevc}. The \pipm,~\kapm, p and \pbar normalised production rates, their differential cross sections, multiplicities a nd the maxima \xipst of the \mbox{\xip=\ln(1/\xp)} distributions are measured for three event samples \zqqbar, ~\zbbbar and \zudsbar, selected from \mbox{}~\zzero deca ys collected by \delphi in 1994. The results are compared to the predictions of the \jetset string fragmentation model and the \herwig cluster fragmentation model. The Modified Leading Logarithm Ap proximation with Local Parton-Hadron Duality is tested. The \xipst dependence on the primary quark flavour is investigated and quantified for the different particle distributions. The \pipm, \kapm, p and \pbar multiplicities are measured with precisions from \%~to~\%. For the \zqqbar and \zbbbar event samples, these improve on previous measurements. The \pipm, \k apm, p and \pbar multiplicities for \zudsbar are presented for the first time
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