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51.
Psoriatic arthritis (PsA) is an inflammatory arthropathy associated with skin and/or nail psoriasis. TNF-α, in addition to its pro-inflammatory role, is an essential cytokine for the host's defense, and its depletion by treatment may facilitate the risk of viral infections or their reactivation. The aim of this study was to evaluate the efficacy and safety of TNF-α blockers in PsA patients with concurrent hepatitis C virus (HCV) infection. This is a multicenter study carried out in four Italian centers specialized in the diagnosis and treatment of PsA. At baseline and after 6 (T6) and 12 months (T12) of therapy, data concerning PsA activity and liver tests were registered. A total of 15 PsA patients with concomitant HCV infection were included in the study. At baseline, 13 patients had low viral load, and liver enzyme tests were within the normal range. During the observation period, these values remained stable. On the other hand, at baseline, a high viral load with slightly increased values of AST and ALT was detected in one patient. At T6 and T12, these values decreased. The remaining patient, at baseline, had low viral load, but with slightly increased AST and ALT values that normalized during the observation period. This is the greatest sample size available in the literature on this topic. The data suggests that anti-TNF-α agents are effective and safe in PsA patients with concomitant HCV. We suggest that the use of anti-TNF-α agents, accompanied by close monitoring, could be a therapeutic option.  相似文献   
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The generation of pancreatic endocrine and exocrine functional precursors from embryonic stem cells (ESCs) is an intriguing opportunity to address cell therapy challenges. The main goal of cellular regeneration is to derive, in vitro, pancreatic progenitor cells (PPCs) that retain the capacity to differentiate following the in vivo developmental ontogeny. In our work, we aim to refine the pancreatic in vitro cellular transitions, through the identification of the intrinsic factors that mark the pancreas budding process at embryonic stage 10.5 (E10.5), in which pancreas precursor specification predominantly occurs. We identified a cohort of genes (Bex1, Nepn, Pcbd1, Prdxdd1, Rnf160, Slc2a1, and Tff3) that marked the pancreas budding genesis, and above all signaled ESC differentiation transitions during pancreatic lineage commitment. Noticeably, we demonstrated that the expression of Nepn marked a naïve pancreatic cellular state that resembled PPC-like specification. Our data considerably improve the comprehension of pancreatic cellular ontogeny, which could be critical for implementing pluripotent stem cells programming and reprogramming toward pancreatic lineage commitment.  相似文献   
54.

OBJECTIVE:

Ovarian mucinous metastases commonly present as the first sign of the disease and are capable of simulating primary tumors. Our aim was to investigate the role of intratumoral lymphatic vascular density together with other surgical-pathological features in distinguishing primary from secondary mucinous ovarian tumors.

METHODS:

A total of 124 cases of mucinous tumors in the ovary (63 primary and 61 metastatic) were compared according to their clinicopathological features and immunohistochemical profiles. The intratumoral lymphatic vascular density was quantified by counting the number of vessels stained by the D2-40 antibody.

RESULTS:

Metastases occurred in older patients and were associated with a higher proportion of tumors smaller than 10.0 cm; bilaterality; extensive necrosis; extraovarian extension; increased expression of cytokeratin 20, CDX2, CA19.9 and MUC2; and decreased expression of cytokeratin 7, CA125 and MUC5AC. The lymphatic vascular density was increased among primary tumors. However, after multivariate analysis, the best predictors of a secondary tumor were a size of 10.0 cm or less, bilaterality and cytokeratin 7 negativity. Lack of MUC2 expression was an important factor excluding metastasis.

CONCLUSIONS:

The higher intratumoral lymphatic vascular density in primary tumors when compared with secondary lesions suggests differences in the microenvironment. However, considering the differential diagnosis, the best discriminator of a secondary tumor is the combination of tumor size, laterality and the pattern of expression of cytokeratin 7 and MUC2.  相似文献   
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IntroductionHealth professionals should work with the notion of risk involved in the health care process. Dental practice risk is of particular interest because it encompasses both aesthetic and functional components. Focusing on guidelines suggested by the World Health Organization and objectives on patient safety, this study has 2 objectives: to present Portuguese medicolegal data on corporal damage evaluation related to iatrogenic sequelae during dental practice and to present updated evidence on patient safety.Materials and methodsA retrospective study was performed by analysing data from the database of the Laboratory of Forensic Dentistry of the Faculty of Medicine, University of Coimbra, Portugal, from 2013 to 2018.ResultsOne hundred seven medicolegal files were selected according to the inclusion and exclusion criteria. Iatrogenic sequelae (73.8%, 79 out of 107) were categorised as risks (60 out of 79) and malpractice (19 out of 79). The risk was associated mostly with mandibular dysfunction and orthodontic treatment (62.2%). Malpractice was mostly associated with neurological deficit and implant rehabilitation (47.4%).Discussion and conclusionGreater attention to these data by professionals was emphasised, especially when considering patient safety and health care quality. This article presents the Portuguese data on professional liability in the field of dental practice, categorising iatrogenic sequelae into risks and malpractice, as well as the oral rehabilitation procedure and timeline.  相似文献   
57.
A 72-year-old female with metastatic breast cancer developed oligoblastic granulocytic leukemia 6 months after initiation of chemotherapy. Cytogenetic examination of the bone marrow cells revealed a balanced t(X;19)(q12;q13.3) as the sole abnormality in 50% of the metaphases. The remaining cells showed a normal female karyotype. The der(19) chromosome displayed consistent folding in the Xq13-q23 region in all metaphases, indicating involvement of the inactive X chromosome in translocation.  相似文献   
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59.
The objective of this observational cohort study was to analyse the age‐related changes of periodic leg movements during sleep using the newest international scoring rules, to expand past analyses, including patients in the paediatric age range, and also to analyse the changes of short‐interval and isolated leg movements during sleep throughout the lifespan. One hundred and sixty‐five patients (84 women) with restless legs syndrome were recruited in the following age groups: 16 preschoolers (≤5 years of age), 29 school‐age children (6–12 years), 19 adolescents (13–17 years), 17 young adults (19–40 years), 47 adults (41–60 years) and 37 seniors (>60 years). Total, periodic, short‐interval and isolated leg movements during sleep and periodicity indexes were obtained by polysomnography. The total index showed (quartic polynomial interpolation) a decrease before 10 years, followed by a steady increase up to 30 years, a relatively stable period until 60 years, and a final increase up to 80 years. This course was almost entirely due to changes in periodic movements. Isolated movements did not change significantly and short‐interval movements showed only an increase in seniors. Our study indicates that, in restless legs syndrome, the total index shows a peculiar and unique course throughout the lifespan, mainly due to periodic movements. These age‐related changes may mirror developmental changes in network complexity known to occur in dopaminergic circuits. These data further confirm the need to better assess the periodicity of leg movements in sleep during the human development period, in order to obtain clinically useful information.  相似文献   
60.

Objective

Cannabinoid receptors are activated in murine macrophages upon exposure to oxidized low-density lipoproteins (oxLDL), and type-1 cannabinoid receptor (CB1R) is considered as a risk factor in atherosclerosis, because it promotes cholesterol accumulation and release of inflammatory mediators. Conversely, accumulated evidence suggests a protective role for type-2 cannabinoid receptor (CB2R). Here, we sought to ascertain whether different elements of the endocannabinoid system (ECS) were activated in human lipid-laden macrophages, and whether CB2R played any role in atherogenesis and inflammation of these cells.

Methods and results

Human macrophages were exposed to oxLDL in order to obtain lipid-laden foam cells. Liquid chromatography/mass spectrometry (LC/MS) was used to measure the production of the endocannabinoids in both macrophages and foam cells, and radiometric assays were performed to measure cannabinoid receptor binding and activity of endocannabinoid metabolizing enzymes. OxLDL accumulation was investigated by confocal imaging, and cytokine production and release were measured by means of flow cytometry and ELISA. The results showed that human macrophages possess a fully functional ECS, which was modulated by oxLDL. Selective CB2R activation reduced cellular oxLDL accumulation, which was associated with decreased expression of CD36 scavenger receptor, and decreased production of TNFα, IL-12 and IL-10. These anti-atherogenic and anti-inflammatory effects were reverted by the selective CB2R antagonist SR144528.

Conclusions

A fully active ECS is present in human macrophages and macrophage-derived foam cells. Selective activation of CB2R reduces CD36-dependent oxLDL accumulation and modulates production of inflammatory cytokines, thus representing a potential therapeutic strategy to combat atherosclerosis.  相似文献   
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