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51.
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Introduction

During root formation, Smad-4 plays a key role during the epithelial–mesenchymal interactions and the Hertwig's epithelial root sheath (HERS) apical proliferation. The root formation and eruption of rat molars is impeded by alendronate treatment due to the inhibition of bone resortion by this drug. The present study aimed to examine the structures affected in the developing root and immunodetect the presence of Smad-4 in rats treated with alendronate.

Methods

Newborn Wistar rats were daily injected 2.5 mg/kg alendronate (ALN) during 9, 12 and 30 days. The controls (CON) were injected with saline. The maxillae were fixed and embedded in paraffin or Spurr resin. Paraffin sections were incubated in Smad-4 antibody that was labelled with DAB. The ultrathin sections were examined in a transmission electron microscope.

Results

In ALN, a short portion of root dentine was formed; the epithelial diaphragm (ED) and the dental follicle (DF) were disorganized by the contact of bone trabeculae. The (CON) molar roots developed normally. Smad-4 labelling was detected in the cytoplasm of fibroblasts and cementoblasts adjacent to the cementum in CON; in ALN group, few ED cells presented weak immunolabelling. Ultrastructurally, the ED and DF appeared disrupted due to the presence of thin bone trabeculae between its cells. It resulted in the lack of apical proliferation of HERS and, consequently, arrest of root formation.

Conclusion

The immunodetection of Smad-4 in the DF cells of ALN specimens indicates that the signalling for the differentiation of these cells into cementum-forming fibroblasts and cementoblasts occurs, despite the impairment of root elongation.  相似文献   
53.
During last years, molecular markers have been increased as prognostic factors routinely screened in acute myeloid leukemia (AML). Recently, an increasing interest has been reported in introducing to clinical practice screening for mutations in the CCAAT/enhancer-binding protein ?? (CEBPA) gene in AML, as it seems to be a good prognostic factor. However, there is no reliable established method for assessing CEBPA mutations during the diagnostic work-up of AMLs. We describe here a straightforward and reliable fragment analysis method based in PCR capillary electrophoresis (PCR-CE) for screening of CEBPA mutations; moreover, we present the results obtained in 151 intermediate-risk karyotype AML patients (aged 16?C80?years). The method gave a specificity of 100% and sensitivity of 93% with a lower detection limit of 1?C5% for CEBPA mutations. The series found 19 mutations and four polymorphisms in 12 patients, seven of whom (58%) presented two mutations. The overall frequency of CEBPA mutations in AML was 8% (n?=?12). CEBPA mutations showed no coincidence with FLT3-ITD or NPM1 mutations. CEBPA mutation predicted better disease-free survival in the group of patients without FLT3-ITD, NPM, or both genes mutated (HR 3.6, IC 95%; 1.0?C13.2, p?=?0.05) and better overall survival in patients younger than 65 of this group without molecular markers (HR 4.0, IC 95%; 1.0?C17.4, p?=?0.05). In conclusion, the fragment analysis method based in PCR-CE is a rapid, specific, and sensitive method for CEBPA mutation screening and our results confirm that CEBPA mutations can identify a subgroup of patients with favorable prognosis in AML with intermediate-risk karyotype.  相似文献   
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Some 70–80% of subjects with psychotic risk syndrome (PRS) have lifetime comorbidity, with depressive disorders being the most common. A high proportion of patients with PRS present nonspecific symptoms which can be confounding factors for diagnosis. Depressive and negative symptoms may be difficult to distinguish and it is important to differentiate them. The aim of this study is to assess the presence of depressive disorder in a child and adolescent sample of PRS and to examine the presence of negative symptoms and detect possible confounding characteristics between them and depressive symptoms. This is a naturalistic multi-site study with subjects who met PRS criteria. A sample of 89 PRS adolescent patients was included. Major depressive disorder (MDD) is the most prevalent comorbid disorder (34.83%). The sample was divided into patients who met criteria for MDD (PRS-MDD, n = 31) and those who did not have this disorder (PRS-ND, n = 44). We obtained significant differences in the attenuated negative symptoms (ANS) between PRS-MDD and PRS-ND (68.18 vs. 90.32%, respectively, p = 0.021). Subjects with MDD presented a higher score in ANS and Hamilton Depression Rating Scale (HDRS). Moreover, we obtained a correlation between negative symptomatology and HDRS score with a higher score on HDRS in subjects with higher negative symptom scores (r = 0.533, p < 0.001). More research is needed to fine tune differentiation between depressive and negative symptoms and learn more about the possible impact of MDD on PRS children and adolescents.

  相似文献   
56.
Background Spending on biological agents has risen dramatically due to the high cost of the drugs and the increased prevalence of spondyloarthritis. Objective To evaluate the annual cost per patient and cost for each biological drug for treating patients with spondyloarthritis from 2009 to 2016, and to calculate factors that affect treatment cost, such as optimizing therapies by monitoring drug serum levels, the use of biosimilar-TNF inhibitors, and official discounts or negotiated rebates in biologicals acquired by the pharmacy department. Method Retrospective, observational study in a Spanish tertiary hospital. Main outcome Annual cost per patient and per drug. Factors that influenced the costs and socio-demographic parameters and disease activity. Results A total of 129, 215, and 224 patients were treated in 2009, 2013, and 2016, respectively. The annual cost per patient decreased: EUR11,604 in 2009, EUR8513 in 2013, and EUR7464 in 2016. The introduction of new drugs drives economic competition, leading to total savings per drug, with discounts reaching 5.8, 12.4, 16.7, 17.7, 13.7, and 24.8% for original infliximab, etanercept, adalimumab, ertolizumab, golimumab, and secukinumab, respectively, while rebates for biosimilar infliximab reached 31.90% in 2016. The number of patients with optimized therapies reached 47.5% in 2016, which led to cost savings of EUR798,614, in addition to savings from official discounts and rebates of EUR252,706 and savings from optimized therapies of EUR545,908 in 2016. Conclusion The cost of biological treatments declined after official discounts, negotiated rebates, and optimized therapies, leading to a significant decrease in the annual cost per patient. The greatest contribution to economic savings in biological therapy according to our study was biological therapy optimization.  相似文献   
57.
OBJECTIVES: Immunofluorescence assay (IFA) has been the standard method for antinuclear antibodies (ANA). To simplify and standardize the ANA test, generic ANA solid phase enzyme immunoassay has been promoted. The objective of the present work has been to study the relationship with IFA and the clinical usefulness of a generic EIA for ANA (COBAS Core HEp-2 ANA EIA, Roche Diagnostics). DESIGNS AND METHODS: We studied 74 healthy individuals, 119 patients with defined systemic autoimmune diseases, 26 patients with other autoimmune diseases, and 490 routine samples sent to laboratory for ANA analysis. RESULTS: Precision study showed intra-assay coefficient of variations (CVs) below 8% and inter-assay CVs below 10%. In relation to IFA, a 0.6 kappa index of agreement was obtained. COBAS-ANA concentrations increased according to IFA titer and greatest COBAS-ANA responses were obtained with pure or mixed homogeneous patterns and centromeric patterns. Analysis of COBAS-ANA response to particular antigenic specificities showed that SS-B, Scl-70 and U1sn-RNP specificities were saturating at high concentrations, whereas Jo-1, SS-A and nuclear and centromeric specificities exhibited lower responses. Elevated serum concentrations of IgG and IgM did not interfere COBAS-ANA, but high serum rheumatoid factor (RF) concentrations produced a decrease of ANA. For systemic lupus erythematosus (SLE) patients, the COBAS-ANA best efficiency was obtained with a cut-off of 0.9, with a sensitivity of 97% and a specificity of 88%, whereas the best IFA-ANA efficiency was obtained with a 1:80 dilution, giving a sensitivity of 90% and a specificity of 99%. There were no differences between areas under ROC curves for COBAS-ANA and IFA-ANA. For other systemic and nonsystemic autoimmune diseases sensitivity and specificity of COBAS-ANA were similar or higher than that of 1:160 IFA-ANA titer. CONCLUSION: Sensitivity and specificity of COBAS Core ANA-EIA for SLE and other systemic and nonsystemic autoimmune diseases, together with performance characteristics make it an adequate automated system for ANA screening.  相似文献   
58.
Hepatotoxicity related to HDS is a growing global health issue. We have undertaken a systematic review of published case reports and case series from LA from 1976 to 2020 to describe the clinical features of HDS related hepatotoxicity in this region. We search in PubMed, Web of Science, Scopus and specific LA databases according to PRISMA guidelines. Only HILI cases published in LA that met criteria for DILI definition were included. Duplicate records or reports that lacked relevant data that precluded establishing causality were excluded. Finally, 17 records (23 cases) were included in this review. Centella asiatica, Carthamus tinctorius, and Herbalife® were the most reported HDS culprit products, the main reason for HDS consumption was weight loss. The clinical characteristics of HDS hepatotoxicity in our study were compared to those of other studies in the USA, Europe and China showing a similar signature with predominance of young females, hepatocellular damage, a high rate of ALF and mortality, more frequent inadvertent re‐challenge and chronic damage. This study underscores the challenge in causality assessment when multi‐ingredients HDS are taken and the need for consistent publication practice when reporting hepatotoxicity cases due to HDS, to foster HDS liver safety particularly in LA.  相似文献   
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Normothermic regional perfusion (NRP) in controlled donation after circulatory death is becoming a popular method due to the favorable results of the grafts procured under this technique. This procedure requires experience, and, sometimes, the availability of extracorporeal membrane oxygenation (ECMO) machines to implement NRP is limited to tertiary hospitals. In order to provide support with NRP in controlled donation after circulatory death across the different hospitals of the Autonomous Community of Madrid, a mobile NRP team was created. In the first 18 months since its creation, the mobile NRP team participated in 33 procurements across nine different hospitals, representing 72% of all controlled donations after circulatory death in the Autonomous Community of Madrid. NRP was successfully performed in 29 (88%) cases, with a mean duration of 69 ± 27 minutes. A total of 39 kidneys, 12 livers, and 5 bilateral lungs were recovered and transplanted. None of the livers were discarded due to an elevation in transaminases during NRP. A mobile NRP team is a feasible option and, in our series, aided in the optimization and recovery of organs from donors after controlled circulatory death in centers where ECMO technology was not available.  相似文献   
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