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31.
32.
Ester García-Oltra Guillem Bori Xavier Tomas Xavier Gallart Sebastian Garcia Alex Soriano 《The Journal of arthroplasty》2013
Different types of hip spacers have been described (hand-made, custom-molded or prefabricated) for treatment of a chronic hip infection. A potential disadvantage of monoblock prefabricated spacer is that it may cause acetabular bone loss. This study assesses the radiological acetabular erosion using an antibiotic-impregnated pre-fabricated polymethylmethacrylate Spacer-G. We retrospectively reviewed the radiographs of thirty five patients who were managed with Spacer-G to treat chronic hip infection. No acetabular erosion were observed in thirty two patients with a mean time from the first to second stage and from the first to the last radiograph of 5.09 and 3.77 months respectively. In three patients the time between the radiographs was more than one year and the second stage was not performed; two developed a protrusion acetabuli whereas the other one a destruction of the acetabular roof. Using a Spacer-G in chronic hip infection treatment for less than one year is not associated with radiological acetabular erosion if the patient is maintained at partial weight bearing. 相似文献
33.
Auxane Buresi Ester Canali Laure Bonnaud Sébastien Baratte 《The Journal of comparative neurology》2013,521(7):1482-1496
Among the Lophotrochozoa, centralization of the nervous system reaches an exceptional level of complexity in cephalopods, where the typical molluscan ganglia become highly developed and fuse into hierarchized lobes. It is known that ganglionic primordia initially emerge early and simultaneously during cephalopod embryogenesis but no data exist on the process of neuron differentiation in this group. We searched for members of the elav/hu family in the cuttlefish Sepia officinalis, since they are one of the first genetic markers of postmitotic neural cells. Two paralogs were identified and the expression of the most neural‐specific gene, Sof‐elav1, was characterized during embryogenesis. Sof‐elav1 is expressed in all ganglia at one time of development, which provides the first genetic map of neurogenesis in a cephalopod. Our results unexpectedly revealed that Sof‐elav1 expression is not similar and not coordinated in all the prospective ganglia. Both palliovisceral ganglia show extensive Sof‐elav1 expression soon after emergence, showing that most of their cells differentiate into neurons at an early stage. On the contrary, other ganglia, and especially both cerebral ganglia that contribute to the main parts of the brain learning centers, show a late extensive Sof‐elav1 expression. These delayed expressions in ganglia suggest that most ganglionic cells retain their proliferative capacities and postpone differentiation. In other molluscs, where a larval nervous system predates the development of the definitive adult nervous system, cerebral ganglia are among the first to mature. Thus, such a difference may constitute a cue in understanding the peculiar brain evolution in cephalopods. J. Comp. Neurol. 521:1482–1496, 2013. © 2012 Wiley Periodicals, Inc. 相似文献
34.
Joost Smolders Ester B. M. Remmerswaal Karianne G. Schuurman Jeroen Melief Corbert G. van Eden René A. W. van Lier Inge Huitinga Jörg Hamann 《Acta neuropathologica》2013,126(4):525-535
Immune surveillance of the central nervous system (CNS) by T cells is important to keep CNS-trophic viruses in a latent state, yet our knowledge of the characteristics of CNS-populating T cells is incomplete. We performed a comprehensive, multi-color flow-cytometric analysis of isolated T cells from paired corpus callosum (CC) and peripheral blood (PB) samples of 20 brain donors. Compared to PB, CC T cells, which were mostly located in the perivascular space and sporadically in the parenchyma, were enriched for cells expressing CD8. Both CD4+ and CD8+ T cells in the CC had a late-differentiated phenotype, as indicated by lack of expression of CD27 and CD28. The CC contained high numbers of T cells expressing chemokine receptor CX3CR1 and CXCR3 that allow for homing to inflamed endothelium and tissue, but hardly cells expressing the lymph node-homing receptor CCR7. Despite the late-differentiated phenotype, CC T cells had high expression of the IL-7 receptor α-chain CD127 and did not contain the neurotoxic cytolytic enzymes perforin, granzyme A, and granzyme B. We postulate that CNS T cells make up a population of tissue-adapted differentiated cells, which use CX3CR1 and CXCR3 to home into the perivascular space, use IL-7 for maintenance, and lack immediate cytolytic activity, thereby preventing immunopathology in response to low or non-specific stimuli. The presence of these cells in this tightly regulated environment likely enables a fast response to local threats. Our results will enable future detailed exploration of T-cell subsets in the brain involved in neurological diseases. 相似文献
35.
36.
Tereza Zelenková Maria Julia Mora Antonello A. Barresi Gladys Ester Granero Davide Fissore 《Journal of pharmaceutical sciences》2018,107(4):1157-1166
This work is focused on the synthesis of polycaprolactone nanoparticles, coated with chitosan, in a confined impinging jet reactor using the solvent displacement method. The role of the various reacting species was investigated, evidencing that a biocompatible polymer, for example, polycaprolactone, is required to support chitosan to obtain a monomodal particle size distribution, with low particle diameters. A surfactant is required to reduce the nanoparticle size (down to a mean diameter of about 260 nm) and obtain a positive zeta potential (about +31 mV), perfectly suitable for pharmaceutical applications. Different surfactants were tested, and Poloxamer 388 appeared to be preferable to polyvinyl alcohol. The effect of the concentration of Poloxamer 388 (in the range 0.5-5 mg mL?1) and of chitosan (in the range 1.5-5 mg mL?1) on both the mean particle size and zeta potential was also investigated, evidencing that chitosan concentration has the strongest effect on both parameters. Finally, the effect of solvent evaporation, quenching and feed flow rate was investigated, showing that the evaporation stage does not affect particle characteristics, quenching is required to avoid particle aggregation, and a minimum liquid flow rate of 80 mL min?1 is required in the considered reactor to minimize the particle size. 相似文献
37.
Scott Yeudall Norbert Leitinger Victor E. Laubach 《American journal of transplantation》2020,20(3):633-640
The role of extracellular purine nucleotides, including adenosine triphosphate (ATP) and adenosine, as modulators of posttransplantation outcome and ischemia‐reperfusion injury is becoming increasingly evident. Upon pathological release of ATP, binding and activation of P2 purinergic surface receptors promote tissue injury and inflammation, while the expression and activation of P1 receptors for adenosine have been shown to attenuate inflammation and limit ischemia‐induced damage, which are central to the viability and long‐term success of allografts. Here we review the current state of the transplant field with respect to the role of extracellular nucleotide signaling, with a focus on the sources and functions of extracellular ATP. The connection between ischemia reperfusion, purinergic signaling, and graft preservation, as well as the role of ATP and adenosine as driving factors in the promotion and suppression of posttransplant inflammation and allograft rejection, are discussed. We also examine novel therapeutic approaches that take advantage of the ischemia‐reperfusion‐responsive and immunomodulatory roles for purinergic signaling with the goal of enhancing graft viability, attenuating posttransplant inflammation, and minimizing complications including rejection, graft failure, and associated comorbidities. 相似文献
38.
The pandemic caused by Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to several hypotheses of functional alteration of different organs. The direct influence of this virus on the male urogenital organs is still to be evaluated. However some hypotheses can already be made, especially in the andrological field, for the biological similarity of the SARS-CoV and SARS-CoV2. As well as SARS-CoV, SARS CoV-2 uses the ‘Angiotensin Converting Enzyme-2’ (ACE2) as a receptor to enter human cells. It was found that ACE2, Angiotensin (1-7) and its MAS receptors are present, over in the lung, also in the testicles, in particular in Leydig and Sertoli cells. A first hypothesis is that the virus could enter the testicle and lead to alterations in testicular functionality. A second hypothesis is that the binding of the virus to the ACE2 receptor, could cause an excess of ACE2 and give rise to a typical inflammatory response. The inflammatory cells could interfere with the function of Leydig and Sertoli cells. Both hypotheses should be evaluated and confirmed, in order to possibly monitor fertility in patients COVID-19+. 相似文献
39.
Antonio Verdejo-Garcia Natalia Albein-Urios Jose Miguel Martinez-Gonzalez Ester Civit Rafael de la Torre Oscar Lozano 《Psychopharmacology》2014,231(21):4179-4187
Rationale
One of the key outstanding challenges in cocaine dependence research is determining who is at risk of relapsing during treatment.Objectives
We examined whether cognitive decision-making profiles predict objectively (hair) indexed cocaine relapse at 3-month follow-up.Methods
Thirty-three cocaine-dependent patients commencing outpatient treatment in a public clinic performed baseline decision-making assessments with the original and variant versions of the Iowa Gambling Task, and provided a 3-cm hair sample 3 months afterwards. Based on Iowa Gambling Tasks’ performance cut-offs, 5 patients had intact decision-making skills, 17 patients showed impaired sensitivity to reward or punishment (impairment in one of the tasks), and 9 patients showed insensitivity to future consequences (impairment in both tasks). Based on a 0.3 ng/mg cocaine cut-off, 23 patients were classified as relapsers and 10 as non-relapsers at the 3-month follow-up.Results
Eighty percent of patients with intact decision-making were abstinent at follow-up, whereas 90 % of patients with insensitivity to future consequences had relapsed. The two subgroups (relapsers and non-relapsers) showed no significant differences on drug use, comorbidities, or psychosocial function, and significantly differed on verbal but not performance IQ. A regression model including decision-making scores and verbal IQ predicted abstinence status with high sensitivity (95 %) and moderately high specificity (81 %).Conclusion
These preliminary findings demonstrate that decision-making profiles are associated with cocaine relapse. Moreover, combined decision-making and IQ assessments provide optimal predictive values over stimulant relapse, yielding significant opportunities for clinical translation. 相似文献40.
Gian C. Winkler Ester Lovsin Barle Giuseppe Galati William M. Kluwe 《Regulatory toxicology and pharmacology : RTP》2014
There is no nationally or internationally binding definition of the term “cytotoxic drug” although this term is used in a variety of regulations for pharmaceutical development and manufacturing of drugs as well as in regulations for protecting medical personnel from occupational exposure in pharmacy, hospital, and other healthcare settings. The term “cytotoxic drug” is frequently used as a synonym for any and all oncology or antineoplastic drugs. Pharmaceutical companies generate and receive requests for assessments of the potential hazards of drugs regularly – including cytotoxicity. This publication is intended to provide functional definitions that help to differentiate between generically-cytotoxic cancer drugs of significant risk to normal human tissues, and targeted cancer therapeutics that pose much lesser risks. Together with specific assessments, it provides comprehensible guidance on how to assess the relevant properties of cancer drugs, and how targeted therapeutics discriminate between cancer and normal cells. The position of several regulatory agencies in the long-term is clearly to regulate all drugs regardless of classification, according to scientific risk based data. Despite ongoing discussions on how to replace the term “cytotoxic drugs” in current regulations, it is expected that its use will continue for the near future. 相似文献