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61.

Background

Recently, neurobiological studies of the cognitive model of depression have become vastly more important, and a growing number of such studies are being reported. However, the relationship between the proportion of positive and negative automatic thought and activity in the prefrontal and temporal cortices has not yet been explored. We examined the relationship between brain activity and the proportion of positive and negative automatic thought in patients with major depressive disorder (MDD), using multi-channel near-infrared spectroscopy (NIRS).

Methods

We recruited 75 individuals with MDD (36 females; mean age=39.23±12.49). They completed the Hamilton Rating Scale for Depression, Automatic Thoughts Questionnaire-Revised, Japanese version of the National Adult Reading Test, and the State-Trait Anxiety Inventory. Brain activation was measured by 52-channel NIRS.

Results

We found that activation in the vicinity of the right superior temporal gyrus is related to a deviation to negative of the proportion of positive and negative thoughts in individuals with MDD. Left dorsolateral prefrontal cortex activity was higher in the group with comparatively frequent positive thought.

Limitations

Our participants were patients taking antidepressant medication, which is known to influence brain activity. Second, the poor spatial resolution of NIRS increases the difficulty of identifying the measurement position.

Conclusions

We found that activation of the prefrontal and temporal cortices is related to the proportion of automatic thoughts in the cognitive model of depression.  相似文献   
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An intracranial collision tumor is a rare lesion composed of two histologically different neoplasms in the same anatomic location. Even more rare is the collision tumor of a solitary fibrous tumor/hemangiopericytoma (SFT/HPC) and meningioma. The patient was a 46-year-old woman who had a 40 × 35 × 30-mm mass in the vermis of the cerebellum. Histologically, the mass consisted of two different components. One component showed the morphology of meningioma (World Health Organization (WHO) grade I), and the other component exhibited small round cell proliferation with hypercellular density, which was revealed to be SFT/HPC (WHO grade III) based on STAT6 immunohistochemistry. STAT6 showed completely different immunohistochemistry results in these two components (nuclear-negative in meningioma and nuclear-positive in SFT/HPC). Since these two neoplasms are associated with different prognoses, they should be distinguished from each other. When meningioma and an SFT/HPC-like lesion are identified morphologically, it is important to recognize the presence of such a collision tumor composed of meningioma and SFT/HPC, and identify the SFT/HPC component by employing STAT6 immunohistochemistry.  相似文献   
66.
Monoclonal antibodies (mAbs) are widely utilized as therapeutic drugs for various diseases, such as cancer, autoimmune diseases, and infectious diseases. Using the avian-derived B cell line DT40, we previously developed an antibody display technology, namely, the ADLib system, which rapidly generates antigen-specific mAbs. Here, we report the development of a human version of the ADLib system and showcase the streamlined generation and optimization of functional human mAbs. Tailored libraries were first constructed by replacing endogenous immunoglobulin genes with designed human counterparts. From these libraries, clones producing full-length human IgGs against distinct antigens can be isolated, as exemplified by the selection of antagonistic mAbs. Taking advantage of avian biology, effective affinity maturation was achieved in a straightforward manner by seamless diversification of the parental clones into secondary libraries followed by single-cell sorting, quickly affording mAbs with improved affinities and functionalities. Collectively, we demonstrate that the human ADLib system could serve as an integrative platform with unique diversity for rapid de novo generation and optimization of therapeutic or diagnostic antibody leads. Furthermore, our results suggest that libraries can be constructed by introducing exogenous genes into DT40 cells, indicating that the ADLib system has the potential to be applied for the rapid and effective directed evolution and optimization of proteins in various fields beyond biomedicine.  相似文献   
67.
Objective:We investigated the efficacy and exposure to radiation in 320-detector row computed tomography fluoroscopy-guided (CTF-guided) interventions.Methods:We analysed 231 320-detector row CTF-guided interventions (207 patients over 2 years and 6 months) in terms of technical success rates, clinical success rates, complications, scanner settings, overall radiation doses (dose–length product, mGy*cm), patient doses of peri-interventional CT series, and interventional CT (including CTF), as a retrospective cohort study. The relationships between patient radiation dose and interventional factors were assessed using multivariate analysis.Results:Overall technical success rate was 98.7% (228/231). The technical success rates of biopsies, drainages, and aspirations were 98.7% (154/156), 98.5% (66/67), and 100% (8/8), respectively. The clinical success rate of biopsies was 93.5% (146/156). All three major complications occurred in chest biopsies. The median total radiation dose was 522.4 (393.4–819.8) mGy*cm. Of the total radiation dose, 87% was applied during the pre- and post-interventional CT series. Post-interventional CT accounted for 24.4% of the total radiation dose. Only 11.4% of the dose was applied by CTF-guided intervention. Multilinear regression demonstrated that male sex, body mass index, drainage, intervention time, and helical scan as post-interventional CT were significantly associated with higher dose.Conclusion:The 320-detector row CTF interventions achieved a high success rate. Dose reduction in post-interventional CT provides patient dose reduction without decreasing the technical success rates.Advances in knowledge:This is the first study on the relationship between various interventional outcomes and patient exposure to radiation in 320-detector row CTF-guided interventions, suggesting a new perspective on dose reduction.  相似文献   
68.
Objectives:The purpose of this study was to evaluate the usefulness of Hounsfield unit (HU) assessment with multislice-CT in the differentiation of radicular cysts (RCs), dentigerous cysts (DCs) and odontogenic keratocysts (OKCs).Methods:In total, 307 odontogenic cysts (RCs, DCs and OKCs) were included in this study. Cysts with lesion diameter <10 mm, cysts with artefacts affecting measurement of HU values, cysts involving infection and recurrent cysts were regarded as exclusion criteria. Images were acquired in three different types of CT scanners: Aquilion ONE, Discovery CT750 HD and SOMATOM Definition Flash. Differences in HU values among scanners and among types of odontogenic cysts were assessed using one-way analysis of variance; multiple comparisons were performed post hoc, using the Tukey–Kramer honestly significant difference test.Results:In total, 164 cysts were analysed in this study (64 RCs, 57 DCs and 43 OKCs). Regardless of the type of lesion, the Aquilion ONE scanner demonstrated a significant difference in HU value, compared with the Discovery CT750 HD scanner. Regardless of CT scanner model, HU values significantly differed between DCs and OKCs (p < 0.0001), as well as between OKCs and RCs (p < 0.0001).Conclusions:HU values were found to vary among CT scanners and should always be associated with other lesion imaging features while interpreting and elaboration diagnostic hypothesis. Notably, the results suggested that OKCs might be able to be differentiated from DCs and RCs by using HU values.  相似文献   
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Statement of problemThe appropriate postpolymerization of stereolithography (SLA) resins with the least effect on dimensional accuracy and with optimal polymerization is unclear.PurposeThe purpose of this in vitro study was to investigate the dimensional accuracy and degree of polymerization of a photopolymer resin for SLA with different postpolymerizing times and temperatures.Material and methodsSixty 1.5-mm-thick specimens were made from clear photopolymer resin with a 3D printer to simulate a maxillary complete denture. They were postpolymerized for different periods (15 and 30 minutes) at 3 different temperatures (40 °C, 60 °C, and 80 °C). Both prepolymerization and postpolymerization gap sizes for each specimen were measured at 5 different locations under a stereomicroscope. The tissue surface was scanned before and after polymerization, and the images were superimposed. The deviation was analyzed by using computer-aided design (CAD) software; root mean square estimates (RMSE) and color map data were obtained. Fourier transform infrared spectrometry was used to determine the degree of conversion (DC) of all specimens. The Kruskal-Wallis and Mann-Whitney tests were used to calculate the difference value of the gap sizes (α=.05). One-way ANOVA and the Tukey test were used for RMSE and DC (α=.05).ResultsThe smallest average change in gap sizes was found at 15 minutes and 40 °C, and the largest change at 30 minutes and 80 °C. The lowest RMSE was obtained at 30 minutes and 40 °C (P<.05). On the color map, a uniform deposited layer was created at 15 minutes and 40 °C and 30 minutes and 40 °C. The highest DC was found at 30 minutes and 60 °C, which differed significantly from 15 minutes and 40 °C (P<.05). The lowest degree of polymerization was found at 30 minutes and 40 °C.ConclusionsThe polymerizing temperature exerted a greater effect than polymerizing time, with lower temperatures leading to improved fit and tissue surface accuracy. The recommended parameters for SLA polymerization are 15 minutes and 40 °C. These conditions offered high dimensional accuracy, favorable surface tissue adaptation, and satisfactory DC.  相似文献   
70.
IntroductionThis study aimed to analyze torque/force generation and transportation in double-curved canals instrumented with 3 types of glide path files using optimum glide path (OGP) motion in comparison with continuous rotation.MethodsSixty simulated double-curved canals were prepared with #10/0.05 or #15/0.03 HyFlex EDM Glidepath files (Coltene/Whaledent, Altstätten, Switzerland) or a #13/0.04 prototype MANI Glidepath file (Tochigi, Japan) using OGP motion or continuous rotation (n = 10 each). Canals were sequentially prepared to 20 mm and 22 mm (full working length) using automated root canal instrumentation and a torque/force analyzing device. Transportation was calculated at 1–9 mm from the apex. Data were compared using 2-way analysis of variance followed by a post hoc simple main effect test with Bonferroni correction and a Kruskal-Wallis test (α = 5%).ResultsAll #10/0.05 instruments fractured. In the 22-mm preparation, the OGP motion resulted in lower clockwise torque and screw-in force than did continuous rotation (P < .05). In the 20-mm preparation, #15/0.03 instruments recorded a lower screw-in force for OGP motion than for continuous rotation (P < .05). Comparing the 2 preparation phases, OGP motion generated no significant differences; however, continuous rotation developed higher clockwise torque and screw-in force in the 22-mm preparation than in the 20-mm preparation (P < .05). There was no significant difference among the tested groups for transportation values.ConclusionsCompared with continuous rotation, OGP motion generated less screw-in force, lower clockwise torque, and similar transportation. The #15/0.03 HyFlex EDM instrument and the #13/0.04 prototype MANI instrument performed similarly well.  相似文献   
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