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81.
Rationale:Chronic pancreatitis (CP) is a risk factor for developing pancreatic ductal adenocarcinoma (PDAC). In addition, a patient with partial pancreatectomy for intraductal papillary mucinous neoplasm (IPMN) can also lead to PDAC. In contrast, IPMN is a distinct disease entity, independent of CP, and there have been few reports that CP is the cause of IPMN. To the best of our knowledge, this is the first clinical case report of the metachronous occurrence of main-duct IPMN and PDAC with a 9 and half-year interval in a patient with chronic alcoholic pancreatitis.Patient concerns:A 50-year-old man with a long medical history of recurrent alcoholic pancreatitis and hepatitis over a decade was diagnosed with another episode of acute pancreatitis based on laboratory findings and clinical symptoms. The patient underwent pylorus-preserving pancreaticoduodenectomy (PPPD) for a small nodular lesion in the main duct of the pancreatic head and was diagnosed with main-duct IPMN low-grade dysplasia and associated fibrosing CP. Nine and a half years later, a 59-year-old man lost 7 kg over 3 months and was diagnosed with new-onset diabetes mellitus.Diagnosis:The patient was diagnosed with metachronous, well-differentiated PDAC with concomitant CP.Interventions:The patient underwent radical antegrade modular pancreatosplenectomy (RAMPS) for a small nodular mass in the remnant pancreas.Outcomes:The patient was healthy for 44 months without evidence of tumor recurrence during clinical follow-up examinations including laboratory findings, tumor marker, and imaging studies.Lessons:Early diagnosis of metachronous pancreatic neoplasia in a patient with chronic pancreatitis could be made by correlating newly developed clinical symptoms and signs with careful radiological examinations.  相似文献   
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ObjectivesPrevious studies have found that the oral health of seniors can affect their physical nutrition and quality of life (QoL). Additionally, poor oral health can lead to the development of dementia, which is associated with decreased cognitive function. This study aimed to examine the impact of geriatric oral health (GOH) on the QoL of Korean seniors and the mediating effects of cognitive function.MethodsWe used data from the seventh Korean Longitudinal Study of Aging conducted in 2018. In total, 4049 seniors were included in our study. We analyzed the impact of GOH on QoL according to 5 mediating domains of cognitive function and control variables. To examine each path of mediating effects, bootstrapping with 5000 iterations was performed with 95% confidence intervals.ResultsOur findings revealed that good GOH had a positive effect on the QoL of seniors. Also, better GOH corresponded to a higher degree of cognitive function within all 5 domains: orientation, memory registration, attention/calculation, memory recall, and language and visuospatial ability. In addition, 3 domains of the 5 domains (attention/calculation, memory recall, and language and visuospatial ability) had significant mediating effects on the relationship between GOH and QoL.ConclusionsThis study suggests that adequate management of GOH is crucial for promoting a better QoL and a high degree of cognitive function among seniors. To prevent cognitive impairment, such as dementia, future studies should take a more targeted approach by examining data according to each cognitive domain and various socio-demographic factors.  相似文献   
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We focus on the importance of accurately describing the flow behaviors of metallic materials to be cold formed; we refer to several valuable examples. We review the typical experimental methods by which flow curves are obtained, in addition to several combined experimental-numerical methods. The characteristics of four fundamental flow models including the Ludwik, Voce, Hollomon, and Swift models are explored in detail. We classify all flow models in the literature into three groups, including the Ludwik and Voce families, and blends thereof. We review the experimental and numerical methods used to optimize the flow curves. Representative flow models are compared via tensile testing, with a focus on the necking point and pre- or post-necking strain hardening. Several closed-form function models employed for the non-isothermal analyses of cold metal forming are also examined. The traditional bilinear C-m model and derivatives thereof are used to describe the complicated flow behaviors of metallic materials at cold forming temperatures, particularly in terms of their applications to metal forming simulations and process optimization.  相似文献   
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We attempt to characterize the degree of skin thermal damage by using multiphoton microscopy to characterize dermal thermal damage. Our results show that dermal collagen and elastic fibers display different susceptibility to thermal injury. Morphologically, dermal collagen starts to denature at 60 degrees C while fracture and aggregation of elastic fibers do not occur until 65 degrees C. With increasing temperatures, the structures of both elastic and collagen fibers deteriorate. While second-harmonic-generation (SHG) imaging is helpful in identifying the denaturation temperature of collagen, autofluorescence (AF) imaging can help to identify the structural alternations of tissue at higher temperatures when SHG signals have decayed. We also employ a ratiometric approach based on the AF-to-SHG index of dermis (ASID) to characterize the degree of dermal thermal damage. Use of the ASID index can bypass the difficulty in analyzing inhomogeneous dermal fibers and show that dermal collagen starts to denature at 60 degrees C. Our results suggest that with additional developments, multiphoton microscopy has potential to be developed into an effective in vivo imaging technique to monitor and characterize dermal thermal damage.  相似文献   
87.

Ethnopharmacological relevance

The expression of matrix metalloproteinase-9 (MMP-9) and cyclooxygenase-2 (COX-2) are pivotal steps in breast cancer pathogenesis. In a previous study, we reported that silibinin suppresses TPA-induced MMP-9 expression through the Raf/MEK/ERK pathway.

Aims of the study

Herein we determined the co-relationship between MMP-9 and COX-2, as well as the effect of silibinin on 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced MMP-9 and COX-2 expression in the human breast cancer cells, MCF-7 and MDA-MB231.

Methods

The toxicity of silibinin was evaluated by Quick Cell Proliferation Assay Kit II. MMP-9 and COX-2 expression were analyzed by Zymography and Western blotting, respectively. Adenoviral constitutively active (CA)-MEK was used to activate MEK/ERK pathway.

Results

The expression of MMP-9 and COX-2 in response to TPA was increased, whereas TPA-induced MMP-9 and COX-2 expression was decreased by silibinin. Our results showed that TPA-induced MMP-9 expression was inhibited by celecoxib in a dose-dependent fashion, but not MMP-1-expression. Both MMP-9 and COX-2 expression were significantly increased by CA-MEK overexpression. In contrast, TPA-induced MMP-9 and COX-2 expression was decreased by UO126 (MEK1/2 inhibitor).

Conclusion

Silibinin down-regulates TPA-induced MMP-9 expression through inhibition of COX-2 expression in breast cancer cells.  相似文献   
88.
Meniscal tear configurations: categorization with MR imaging   总被引:7,自引:0,他引:7  
OBJECTIVE: The purpose of this study was to evaluate the accuracy of MR imaging for categorizing the configuration of meniscal tears of the knee. MATERIALS AND METHODS: Fast spin-echo MR images obtained at 1.5 T from 110 patients who had meniscal tears identified at arthroscopy were retrospectively and independently classified by two reviewers into five configurations: horizontal, longitudinal, radial, oblique, and complex. MR imaging categorization was compared with arthroscopic results as the standard of reference. Data were also analyzed with longitudinal and oblique tears combined because these usually are reparable, and with horizontal, radial, and complex tears combined because these usually are not reparable. Interobserver and intraobserver agreements were calculated using kappa coefficients. RESULTS: At arthroscopy, meniscal tears were categorized as horizontal (n = 44), longitudinal (n = 34), complex (n = 22), radial (n = 11), and oblique (n = 5). Sensitivity, specificity, and accuracy of each reviewer for the reparable tears were 82%, 92%, and 89%; and 59%, 97%, and 84%, respectively. Interobserver agreements were fair between reviewer 1 and the first and second interpretations of reviewer 2 (kappa = 0.25, p < 0.005; and kappa = 0.21, p < 0.05, respectively). Intraobserver agreement was substantial (kappa = 0.71, p < 0.001). CONCLUSION: MR imaging was accurate for predicting reparable meniscal tears and was sensitive for the determination of nonreparable tears.  相似文献   
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Inflammation Research - This study aimed to evaluate the protective effect of igalan, a sesquiterpene lactone isolated from Inula helenium (L.), on inhibiting inflammation, regulating the epidermal...  相似文献   
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