The effects of alloy composition on microstructural, especially the formation of large intermetallic compounds, and mechanical properties of various Sn–Ag–Cu solder joints were investigated. The ...range of Ag–Cu content of Sn–Ag–Cu alloys was from 3.0 wt.%Ag–0.5 wt.%Cu to 3.9Ag–0.7 wt.%Cu. The high Ag content alloys exhibit the formation of large Ag
3Sn platelets especially at the solder–reaction layer interfaces, regardless of the kind of substrates. Long Cu
6Sn
5 whiskers are formed in all the solder–Cu joints and the high Cu content solder joints. Those whiskers have two shapes of needle and of hollow types. For the high Cu content solder joints with a 42 alloy substrate, long Ni–Cu–Sn whiskers are also formed at the interface and in the solder. The presence of large Ag
3Sn platelets does not degrade strength directly, but affects fracture mode. Large Ag
3Sn platelets induce brittle fracture at an interface and provide crack initiation sites. In order to avoid the formation of the large intermetallic compounds, especially Ag
3Sn platelets, the optimum composition of Sn–Ag–Cu alloy lies in the lower Ag–Cu content.
XIAP-associated factor 1 (XAF1) is a new candidate tumor suppressor, which has been known to exert proapoptotic effects by interfering with the caspase-inhibiting activity of XIAP. To explore the ...XAF1's candidacy for a suppressor in urogenital tumorigenesis, we investigated the XAF1 status in a series of cancer cell lines and primary tumors derived from the bladder, kidney and prostate. Expression of XAF1 transcript was undetectable or extremely low in 60% (3/5) of bladder, 66% (10/15) of kidney, and 100% (3/3) prostate cancer cell lines. Abnormal reduction of XAF1 was also found in 33% (18/55) of primary bladder and 40% (8/20) of primary kidney tumors, and showed a correlation with advanced stage and high grade of bladder tumor. Hypermethylation at 14 CpG sites in the 5' proximal region of the XAF1 promoter was highly prevalent in cancers versus adjacent normal or benign tissues and tightly associated with reduced gene expression. XAF1 expression enhanced the apoptotic response of tumor cells to chemotherapeutic agents, such as etoposide or 5-FU. While XAF1 expression did not influence the subcellular distribution or expression of XIAP, it elevated the protein stability of p53 and its target gene expression. Moreover, the apoptosis-sensitizing and growth suppression function of XAF1 was markedly impeded by blockade of p53 function. Collectively, our study demonstrates that epigenetic alteration of XAF1 is frequent in human urogenital cancers and may contribute to the malignant progression of tumors by rendering tumor cells a survival advantage partially through the attenuated p53 response to apoptotic stresses.
This study was conducted to elucidate the association between clinical and angiographic characteristics and stroke types in adult Moyamoya disease that has been rarely evaluated.
We analyzed the ...clinical and radiologic data obtained from a retrospective adult Moyamoya disease cohort with acute strokes, which were classified into 7 categories: large-artery infarct, hemodynamic infarct, perforator infarct, deep intracerebral hemorrhage, lobar intracerebral hemorrhage, intraventricular hemorrhage, and SAH. With conventional angiography, which was performed in the hemispheres with acute strokes, the Suzuki angiographic stage, intracranial aneurysm, major artery occlusion, and collateral vessel development were confirmed within 1 month of stroke onset.
This study included 79 patients with acute ischemic stroke and 96 patients with acute hemorrhagic stroke. The angiographic stage had a strong tendency to be more advanced in the hemorrhagic than the ischemic patients (P = .061). Intracranial aneurysms were more frequently found in the hemorrhagic than ischemic or control hemispheres (P = .002). Occlusions of the anterior cerebral artery and development of fetal-type posterior cerebral artery were more frequently observed in the hemorrhagic than the ischemic (P = .001 and .01, respectively) or control hemispheres (P = .011 and .013, respectively). MCA occlusion (P = .039) and collateral flow development, including the ethmoidal Moyamoya vessels (P = .036) and transdural anastomosis of the external carotid artery (P = .022), occurred more often in the hemorrhagic than the ischemic hemispheres. Anterior cerebral artery occlusion occurred more frequently in patients with deep intracerebral hemorrhage or intraventricular hemorrhage than with lobar intracerebral hemorrhage (P = .009).
In adult Moyamoya disease, major artery occlusion and collateral compensation occurred more often in the hemorrhagic than in the ischemic hemispheres. Thus, anterior cerebral artery occlusion with or without MCA occlusion and intracranial aneurysms may be the main contributing factors to hemorrhagic stroke in adult patients with Moyamoya disease.
The microstructures and tensile properties of three typical Sn–Ag–Cu alloys, Sn–3.0wt.%Ag–0.5wt.%Cu, Sn–3.5wt.%Ag–0.7wt.%Cu and Sn–3.9wt.%Ag–0.6wt.%Cu, prepared under three different cooling ...conditions were evaluated after casting. The microstructures of all rapidly cooled specimens consisted of the eutectic phase of β-Sn with fine fibrous Ag
3Sn dispersion surrounding primary β-Sn grains. The slowly cooled Sn–3.5Ag–0.7Cu and Sn–3.9Ag–0.6Cu alloys exhibited additional large primary Ag
3Sn platelets, while the Sn–3.0Ag–0.5Cu did not. For all alloys, both ultimate tensile strength and 0.2% proof stress increased with increasing strain-rates in tensile tests. Lowering cooling speed decreased tensile strength. Elongation increased with an increasing strain rate from 10
−5 to 10
−2 s
−1, and decreased slightly at 10
−1 s
−1 for the rapidly cooled specimens. Elongation remarkably decreased for the slowly cooled Sn–3.5Ag–0.7Cu and Sn–3.9Ag–0.6Cu alloys, a degradation attributable to the formation of large primary Ag
3Sn platelets.
Combining topology and superconductivity provides a powerful tool for investigating fundamental physics as well as a route to fault-tolerant quantum computing. There is mounting evidence that the ...Fe-based superconductor FeTe0.55Se0.45 (FTS) may also be topologically nontrivial. Should the superconducting order be s±, then FTS could be a higher order topological superconductor with helical hinge zero modes (HHZMs). To test the presence of these modes, we have fabricated normal-metal/superconductor junctions on different surfaces via 2D atomic crystal heterostructures. As expected, junctions in contact with the hinge reveal a sharp zero bias anomaly that is absent when tunneling purely into the c-axis. Additionally, the shape and suppression with temperature are consistent with highly coherent modes along the hinge and are incongruous with other origins of zero bias anomalies. Additional measurements with soft-point contacts in bulk samples with various Fe interstitial contents demonstrate the intrinsic nature of the observed mode. Thus, we provide evidence that FTS is indeed a higher order topological superconductor.
Summary
Sarcopenia means the progressive loss of skeletal muscle mass and strength with aging. In this study, we found that insulin resistance, chronic kidney disease stage 3, and osteoporosis at the ...femur neck were closely associated with sarcopenia in elderly men. These conditions modified to slow down the progression of sarcopenia.
Introduction
Sarcopenia is known to have multiple contributing factors; however, its modifiable risk factors have not yet been determined. The aim of this study was to identify the most influential and modifiable risk factors for sarcopenia in elderly.
Methods
This was a population-based, cross-sectional study using data from the Fourth Korea National Health and Nutrition Examination Survey (KNHANES IV), 2008–2009. This study included 940 men and 1,324 women aged 65 years and older who completed a body composition analysis using dual-energy X-ray absorptiometry. Sarcopenia was defined as an appendicular skeletal muscle mass divided by height
2
of less than 1 standard deviation below the sex-specific mean for a younger reference group.
Results
Using univariate analysis, age, body mass index (BMI), homeostasis model assessment for insulin resistance (HOMA-IR), limitations in daily activities, regular exercise, high-risk drinking, family income, osteoporosis, daily energy, and protein intake were associated with sarcopenia in men; age, BMI, limitations in daily activities, regular exercise, occupation, osteoporosis at the total hip, and daily energy intake were associated with sarcopenia in women. In the multivariate logistic regression analysis, HOMA-IR ≥2.5 (odds ratio OR for sarcopenia, 2.27; 95 % confidence interval CI, 1.21–4.25), chronic kidney disease stage 3 (OR, 3.13; 95 % CI, 1.14–8.61), and osteoporosis at the femur neck (OR, 6.83; 95 % CI, 1.08–43.41) were identified as risk factors for sarcopenia in men.
Conclusions
Insulin resistance, chronic kidney disease, and osteoporosis at the femur neck should be modified to prevent the acceleration of skeletal muscle loss in elderly men.
Abstract In the present study, we examined the neuroprotective effects and mechanisms of implanted human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) in ischemic stroke. hUC-MSCs were ...isolated from the endothelial/subendothelial layers of the human umbilical cord and cultured. Twenty days after the induction of in vitro neuronal differentiation, about 77.4% of the inoculated hUC-MSCs displayed morphological features of neurons and expressed neuronal cell markers like TU-20, Trk A, NeuN, and NF-M. However, functionally active neuronal type channels were not detected by electrophysiological examination. Before, during, or one day after in vitro neuronal differentiation, the hUC-MSCs produced granulocyte-colony stimulating factor, vascular endothelial growth factor, glial cell line-derived neurotrophic factor, and brain-derived neurotrophic factor. In an in vivo study, implantation of the hUC-MSCs into the damaged hemisphere of immunosuppressed ischemic stroke rats improved neurobehavioral function and reduced infarct volume relative to control rats. Three weeks after implantation, most of the implanted hUC-MSCs were present in the damaged hemisphere; some of these cells expressed detectable levels of neuron-specific markers. Nestin expression in the hippocampus was increased in the hUC-MSC-implanted group relative to the control group. Since the hUC-MSCs were both morphologically differentiated into neuronal cells and able to produce neurotrophic factors, but had not become functionally active neuronal cells, the improvement in neurobehavioral function and the reduction of infarct volume might be related to the neuroprotective effects of hUC-MSCs rather than the formation of a new network between host neurons and the implanted hUC-MSCs.
Summary
The aim of this study was to examine the gender-specific association between sarcopenia and bone geometry/metabolic parameters. Low muscle mass was associated with greater deterioration of ...bone than in deterioration of glucose or lipid profiles. This bone–muscle relationship was more prominent in men than in women.
Introduction
There are few studies that report on gender differences in the effects of low muscle mass on bone and metabolic parameters in elderly subjects. This study aimed to assess the gender-specific influence of muscle mass on bone and metabolic parameters.
Methods
A total of 2,264 participants (940 men and 1,324 women) whose age ranged from 65 to 92 years were analyzed using data from The Fourth Korea National Health and Nutrition Examination Surveys (2008–2009). We measured bone mineral density (BMD) and appendicular muscle mass using the dual-energy X-ray absorptiometry and also measured metabolic profiles.
Results
The age-related trend in bone and muscle coincided in men but not in women. Femoral neck (FN) and total hip (TH) BMD were highly correlated with muscle mass in both genders. However, in women, this correlation was not significant in the lumbar spine (LS). In addition, this positive correlation was stronger in the FN or TH than in the LS and was stronger in men than in women. Subjects with sarcopenia were at a higher risk for osteoporosis in the FN, TH, and LS in men, and in the TH and FN in women. The degree of association between muscle mass and metabolic profiles was relatively very weak.
Conclusion
Bone–muscle relationship was more prominent in men than in women. The gender differences in bone–muscle relationship may be helpful for the development of gender-specific preventive strategies in the elderly, especially in men.
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