We report infrared studies of the Landau level (LL) transitions in single layer graphene. Our specimens are density tunable and show in situ half-integer quantum Hall plateaus. Infrared transmission ...is measured in magnetic fields up to B=18 T at selected LL fillings. Resonances between hole LLs and electron LLs, as well as resonances between hole and electron LLs, are resolved. Their transition energies are proportional to sqrtB, and the deduced band velocity is (-)c approximately equal to 1.1 x 10(6) m/s. The lack of precise scaling between different LL transitions indicates considerable contributions of many-particle effects to the infrared transition energies.
Urothelial carcinoma (UC) carcinogenesis has been hypothesized to occur through epigenetic repression of tumor-suppressor genes (TSGs). By quantitative real-time polymerase chain reaction array, we ...found that one potential TSG, angiopoietin-like 4 (ANGPTL4), was expressed at very low levels in all bladder cancer cell lines we examined. Previous studies had demonstrated that ANGPTL4 is highly expressed in some cancers, but downregulated, by DNA methylation, in others. Consequently, owing to these seemingly conflicting functions in distinct cancers, the precise role of ANGPTL4 in the etiology of UC remains unclear. In this study, using methylation-specific PCR and bisulfite pyrosequencing, we show that ANGPTL4 is transcriptionally repressed by DNA methylation in UC cell lines and primary tumor samples, as compared with adjacent noncancerous bladder epithelium. Functional studies further demonstrated that ectopic expression of ANGPTL4 potently suppressed UC cell proliferation, monolayer colony formation in vitro, and invasion, migration, and xenograft formation in vivo. Surprisingly, circulating ANGPTL4 was significantly higher in plasma samples from UC patients than normal control, suggesting it might be secreted from other cell types. Interestingly, our data also indicated that exogenous cANGPTL4 could promote cell proliferation and cell migration via activation of signaling through the Erk/focal adhesion kinase axis. We further confirmed that mouse xenograft tumor growth could be promoted by administration of exogenous cANGPTL4. Finally, immunohistochemistry demonstrated that ANGPTL4 was downregulated in tumor cells but overexpressed in tumor adjacent stromal tissues of muscle-invasive UC tissue samples. In conclusion, our data support dual roles for ANGPTL4 in UC progression, either as a tumor suppressor or oncogene, in response to microenvironmental context.
Brominated flame retardants (BFRs) are stable environmental contaminants known to exert endocrine‐disrupting effects. Developmental exposure to polybrominated diphenyl ethers (PBDEs) is correlated ...with impaired thyroid hormone signaling, as well as estrogenic and anti‐androgenic effects. As previous studies have focused on a single congener or technical mixture, the purpose of the current study was to examine the effects of gestational and early postnatal exposure to an environmentally relevant mixture of BFRs designed to reflect house dust levels of PBDEs and hexabromocyclododecane on postnatal developmental outcomes. Pregnant Sprague‐Dawley rats were exposed to the PBDE mixture from preconception to weaning (PND 21) through the diet containing 0, 0.75, 250, and 750 mg mixture/kg diet. BFR exposure induced transient reductions in body weight at PND 35 in male and from PND 30–45 in female offspring (250 and 750 mg/kg). Liver weights (PND 21) and xenobiotic metabolizing enzyme activities (PND 21 and 46) were increased in both male and female offspring exposed to 250 and 750 mg/kg diets. Furthermore, serum T4 levels were reduced at PND 21 in both,male and female offspring (250 and 750 mg/kg). At PND 21, Serum alkaline phosphatase (ALP) was decreased in males exposed to 750 mg/kg dietat, and females exposed to 250 and 750 mg/kg diets. At PND 46 ALP was significantly elevated in males (250 and 750 mg/kg). Variations in the cervical vertebrae and phalanges were observed in pups at PND 4 (250 and 750 mg/kg). Therefore, BFR exposure during gestation through to weaning alters developmental programming in the offspring. The persistence of BFRs in the environment remains a cause for concern with regards to developmental toxicity
Highlights • In DFA, P2 agonist activates its receptor on PNGF that releases glutamate. • Glutamate activates neuronal NOS/GC, resulting in increase of CCA blood flow. • P2 agonist and NO precursor ...do not cause PNGF and other neurons to release ATP. • There is no P2 receptor on PNCN. • Cerebral vascular diseases may be related to poor regulation of DFA.
Converging lines of evidence implicate the beta‐amyloid peptide (Aβ) as causative in Alzheimer's disease. We describe a novel class of compounds that reduce Aβ production by functionally inhibiting ...γ‐secretase, the activity responsible for the carboxy‐terminal cleavage required for Aβ production. These molecules are active in both 293 HEK cells and neuronal cultures, and exert their effect upon Aβ production without affecting protein secretion, most notably in the secreted forms of the amyloid precursor protein (APP). Oral administration of one of these compounds, N‐N‐(3,5‐difluorophenacetyl)‐l‐alanyl‐S‐phenylglycine t‐butyl ester, to mice transgenic for human APPV717F reduces brain levels of Aβ in a dose‐dependent manner within 3 h. These studies represent the first demonstration of a reduction of brain Aβin vivo. Development of such novel functional γ‐secretase inhibitors will enable a clinical examination of the Aβ hypothesis that Aβ peptide drives the neuropathology observed in Alzheimer's disease.
To investigate whether the survival results after resection of hepatocellular carcinoma (HCC) have improved within the past decade by an analysis of a prospective cohort of patients over a 10-year ...period.
The surgical death rate after resection of HCC has greatly improved in recent years, but the long-term prognosis remains unsatisfactory. It remains unknown whether the survival results after resection of HCC have improved within the past decade.
The clinicopathologic and follow-up data of 377 patients who underwent curative resection of HCC between January 1989 and January 1999 were prospectively collected. These patients were categorized according to two time periods: before 1994 (group 1, n = 136) and after 1994 (group 2, n = 241). The two groups were compared for clinicopathologic data and survival results. The prognostic factors for disease-free survival were further analyzed to identify the factors that might have led to improved survival outcomes.
The overall and disease-free survival results were significantly better in group 2 compared with group 1. Patients in group 2 had significantly higher proportions of subclinical presentation, small tumors, and tumors of early pTNM stage. There were also significantly lower frequencies of histologic margin involvement, less intraoperative blood loss, and a lower transfusion rate in group 2. By multivariate analysis, early pTNM stage, subclinical HCC, and no perioperative transfusion were independent favorable prognostic factors for disease-free survival.
Significant improvement of overall and disease-free survival results after resection of HCC has been achieved within the past decade as a result of advances in the diagnosis and surgical management of HCC. Earlier diagnosis of HCC by better imaging modalities, increased detection of subclinical HCC by screening of high-risk patients, and a reduced perioperative transfusion rate were identified as the major contributory factors for the improved outcomes.
To demonstrate the risk of cataract associated with radiation exposure from neuro-interventional procedures.
This was a nationwide population-based, matched-cohort study. The exposed group (group E) ...comprised patients diagnosed with an aneurysm, cerebrovascular system anomaly, or subarachnoid haemorrhage who underwent a neuro-interventional procedure, such as brain digital subtraction angiography or endovascular embolisation. The comparison group (group C) included subjects who were never exposed to radiation from neuro-interventional procedures and were propensity score-matched by the date of enrolment, age, sex, and associated comorbidities. Multiple Cox proportional hazard regression analysis was used to estimate the hazard ratio (HR) of cataract risk due to radiation exposure while adjusting for potential confounding factors.
There were 838 patients and 3,352 matched subjects in groups E and C, respectively. The incidence of cataracts was significantly greater among subjects in group E (adjusted HR aHR = 1.88; 95% confidence interval CI = 1.08–3.26), especially those aged >40 years (aHR = 2.14; 95% CI = 1.16–3.94). The number of computed tomography examinations was positively correlated, but not statistically significant, with an increased risk of cataract occurrence.
Neuro-interventional procedures might be significantly associated with an increased risk of cataract occurrence.
•Neurointerventional procedures might be significantly associated with an increased risk of cataract.•The putative excess risk of cataract after neurointerventional procedures is estimated at 88%.•The risk of cataract was significantly increased among exposed patients aged 40–49 years.•Ophthalmological examinations might be helpful for patients after neurointerventional procedures.
BACKGROUND: There are limited neuroprotective treatment options for patients with aneurysmal subarachnoid hemorrhage (SAH). Cerebrolysin, a brain-specific proposed pleiotropic neuroprotective agent, ...has been suggested to improve global functional outcomes in ischemic stroke. We investigated the efficacy, safety and feasibility of administering Cerebrolysin for SAH patients.
This was a prospective, randomized, double-blind, placebo-controlled, single-center, parallel-group pilot study. Fifty patients received either daily Cerebrolysin (30 ml/day) or a placebo (saline) for 14 days (25 patients per study group). The primary endpoint was a favorable Extended Glasgow Outcome Scale (GOSE) of 5 to 8 (moderate disability to good recovery) at six-months. Secondary endpoints included the modified Ranking Scale (mRS), the Montreal Cognitive Assessment (MOCA) score, occurrence of adverse effects and the occurrence of delayed cerebral ischemia (DCI).
No severe adverse effects or mortality attributable to Cerebrolysin were observed. No significant difference was detected in the proportion of patients with favorable six-month GOSE in either study group (odds ratio (OR): 1.49; 95% confidence interval (CI): 0.43-5.17). Secondary functional outcome measures for favorable six-month recovery i.e. a mRS of 0 to 3 (OR: 3.45; 95% CI 0.79-15.01) were comparable for both groups. Similarly, there was no difference in MOCA neurocognitive performance (p-value: 0.75) and in the incidence of DCI (OR: 0.85 95% CI: 0.28-2.59).
Use of Cerebrolysin in addition to standard-of-care management of aneurysmal SAH is safe, well tolerated and feasible. However, the neutral results of this trial suggest that it does not improve the six-month global functional performance of patients.
Name of Registry: ClinicalTrials.gov Trial Registration Number: NCT01787123 . Date of Registration: 8th February 2013.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We combined Raman and infrared vibrational spectroscopies with complementary lattice dynamics calculations and magnetization measurements to reveal the dynamic aspects of charge-lattice-spin coupling ...in CoN(CN)22. Our work uncovers electron-phonon coupling as a magnetic field-driven avoided crossing of the low-lying Co2+ electronic excitation with two ligand phonons and a magnetoelastic effect that signals a flexible local CoN6 environment. Their simultaneous presence indicates the ease with which energy is transferred over multiple length and time scales in this system.
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