35 research outputs found
Association between intra-radicular posts and periapical lesions in endodontically treated teeth
Introduction: A significant number of endodontically treated teeth restored with posts have associated periapical lesions, and several authors have discussed the probable causes of the development of these. Attention has been focused on restorative procedures performed after endodontic treatment and their association with the prognosis of endodontic therapy because a number of root-filled teeth will require post- and core-retained restorations. Purpose: The purpose of this study was to evaluate, by examination of periapical radiographs, whether the placement of intra-radicular posts in endodontically treated teeth may act as a risk factor for development of periapical lesions. Material and Methods: This case-control study analyzed periapical radiographs of 72 endodontically treated teeth with coronal restorations. All radiographs were obtained from a single private practice. Specimens were assigned to 2 groups: Group 1 (control) was composed of teeth without periapical lesions and Group 2 (case) was composed of teeth with periapical lesions. The number of teeth with and without posts in each group was recorded. Three calibrated examiners analyzed the radiographs visually under X4 magnification. Results: In Group 1, 28 (65.1%) out of 43 teeth were restored with posts. In Group 2, 24 (82.8%) out of 29 teeth had intra-radicular posts. The interpretation of chi-square test showed that these percentages were not significantly different (x²=2.687; p=0.101). Odds ratio was 2.571 (0.815-8.118), which indicates that there was no statistically significant association between periapical lesions and posts. Conclusion: Intra-radicular posts placed in endodontically treated teeth were not a significant risk factor for development of periapical lesions in the practice where the cohort of patients was treated
Influence of delayed pouring on irreversible hydrocolloid properties
The aim of this study was to evaluate the physical properties of irreversible hydrocolloid materials poured immediately and after different storage periods. Four alginates were tested: Color Change (Cavex); Hydrogum (Zhermack); Hydrogum 5 (Zhermack); and Hydro Print Premium (Coltene). Their physical properties, including the recovery from deformation (n = 3), compressive strength (n = 3), and detail reproduction and gypsum compatibility (n = 3), were analyzed according to ANSI/ADA specification no. 18. Specimens were stored at 23ºC and humidity and were then poured with gypsum immediately and after 1, 2, 3, 4, and 5 days. The data were analyzed by two-way analysis of variance (ANOVA) and Tukey's test at p < 0.05. All of the alginate impression materials tested exhibited detail reproduction and gypsum compatibility at all times. Hydro Print Premium and Hydrogum 5 showed recovery from deformation, as established by ANSI/ADA specification no. 18, after 5 days of storage. As the storage time increased, the compressive strength values also increased. Considering the properties of compounds' recovery from deformation, compressive strength, and detail reproduction and gypsum compatibility, irreversible hydrocolloids should be poured immediately
Optimal daily configuration of a distribution network based on photovoltaic generation and system loading using imperialist competitive algorithm and selection approach
This paper presents a new method to determine the best configuration for a distribution system for a day considering Photovoltaic (PV) generation and daily load profile. In the first part, the hourly optimal configuration for a day is obtained by using Imperialist Competitive Algorithm (ICA) and in second part, a selective approach based on minimum total daily power loss is used to select the optimal daily configuration. The proposed method is validated on IEEE 33 bus test system
Behavioral and Neurophysiological Implications of Pathological Human Tau Expression in Serotonin Neurons
Alzheimer’s disease (AD) is a progressive degenerative
disorder
that results in a severe loss of brain cells and irreversible cognitive
decline. Memory problems are the most recognized symptoms of AD. However,
approximately 90% of patients diagnosed with AD suffer from behavioral
symptoms, including mood changes and social impairment years before
cognitive dysfunction. Recent evidence indicates that the dorsal raphe
nucleus (DRN) is among the initial regions that show tau pathology,
which is a hallmark feature of AD. The DRN harbors serotonin (5-HT)
neurons, which are critically involved in mood, social, and cognitive
regulation. Serotonergic impairment early in the disease process may
contribute to behavioral symptoms in AD. However, the mechanisms underlying
vulnerability and contribution of the 5-HT system to AD progression
remain unknown. Here, we performed behavioral and electrophysiological
characterizations in mice expressing a phosphorylation-prone form
of human tau (hTauP301L) in 5-HT neurons. We found that pathological
tau expression in 5-HT neurons induces anxiety-like behavior and alterations
in stress-coping strategies in female and male mice. Female mice also
exhibited social disinhibition and mild cognitive impairment in response
to 5-HT neuron-specific hTauP301L expression. Behavioral alterations
were accompanied by disrupted 5-HT neuron physiology in female and
male hTauP301L expressing mice with exacerbated excitability disruption
in females only. These data provide mechanistic insights into the
brain systems and symptoms impaired early in AD progression, which
is critical for disease intervention
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Unfavorable transcriptome profiles and social disadvantage in hematopoietic cell transplantation: a CIBMTR analysis.
Patient-reported outcomes (PROs) capture subjective social determinants of health (SDOHs), which can affect health outcomes through the stress response pathway. The conserved transcriptional response to adversity (CTRA) is a stress-mediated proinflammatory transcriptomic pattern that has been linked to adverse hematopoietic cell transplant (HCT) outcomes. This study examined the association of pretransplant CTRA with patient-reported SDOHs in allogeneic HCT recipients. In this cross-sectional study, pre-HCT SDOH-related PROs included the 36-Item Short Form Health Survey and the Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT). CTRA was assessed by RNA sequencing of whole blood specimens, with mixed effects linear regression models relating CTRA expression to PRO scores while controlling for age, sex, race, disease, and performance status. Among 121 patients, the median age was 54 years, 42% were female, and 91% were White. CTRA was elevated in participants reporting lower scores on the FACT-BMT (P = .003), including the general (P = .003) and BMT-specific (P = .014) components. Effects were driven by the social well-being domain (P = .0001). This corresponded to an 8% to 15% difference in CTRA RNA expression across a 4 standard deviation range in patient-reported SDOHs. Ancillary bioinformatics analyses confirmed the association of well-being with reduced proinflammatory transcription pathway activity [cyclic AMP response element-binding protein, (CREB), NF-κB, and activating protein-1 (AP-1)]. In conclusion, HCT-treated patients who experience unfavorable social conditions show elevated CTRA expression in pretransplant blood samples. These data highlight the biologic sequelae of social well-being and community context and suggest a potential molecular mechanism for the impact of social gradients in HCT outcomes. Targeting this pathway could optimize outcomes in this high-risk population