Retention behavior of nucleosides and nucleobases on a 3 µm undecylenic acid-functionalized silica column in per aqueous liquid chromatography and hydrophilic interaction liquid chromatography separation modes.

A 3 µm undecylenic acid-functionalized stationary phase (UAS) was prepared for the separation of nucleosides and nucleobases using per aqueous liquid chromatography (PALC) and hydrophilic interaction liquid chromatography (HILIC). The retention behaviors of nucleosides and nucleobases in PALC and HILIC modes were explored by adjusting parameters such as water content, buffer concentration, pH of the mobile phase and column temperature. The experimental data and separation chromatogram demonstrated that PALC could provide retention comparable to that of HILIC for nucleosides and nucleobases. Comparative studies using diluted adenosine solutions evaluated theoretical plates and peak shape for the same retention factors (between 0.25 and 5.0) in PALC and HILIC. There was no buffer component in the mobile phases used to operate the comparisons. HILIC mode is more efficient for adenosine than PALC mode at low retention factors. It's the exact opposite phenomenon for high retention factors. It is proposed that the mass transfer of adenosine between the UAS, the water-rich layer and the ACN-rich mobile phase in HILIC is relatively slow. Given the significant use of toxic ACN in HILIC, PALC emerges as a safer and more effective alternative for separating nucleosides and nucleobases.

A facile approach to undecylenic acid-functionalized stationary phases for per aqueous liquid chromatography.

Green chromatography techniques using low-toxic mobile phase are getting increasingly attention in recent years. The core is developing stationary phases that possess adequate retention and separation under the mobile phase of high content water. Using thiol-ene click chemistry, an undecylenic acid-bonded silica stationary phase (UAS) was prepared in a facile manner. Elemental analysis (EA), solid-state 13C NMR spectroscopy and Fourier transform infrared spectrometry (FT-IR) confirmed the successful preparation of UAS. The synthesized UAS was employed for per aqueous liquid chromatography (PALC), which uses little organic solvent during separation. Due to the hydrophilic carboxy, thioether group and hydrophobic alkyl chains of the UAS, various categories of compounds (including nucleobases, nucleosides, organic acids and basic compounds) with different properties can achieve enhanced separation under the mobile phase of high content water compared with commercial C18 and silica stationary phases. Overall, our present UAS stationary phase shows excellent separation ability toward highly polar compounds and meets the requirements of green chromatography.

Prevalence of amblyopia among preschool children in central south China.

AIM: To determine the prevalence and factors associated with amblyopia among children aged 30-83mo in central south of China. METHODS: A population-based, cross-sectional study was conducted in children aged 30-83mo in Changsha (an urban city) and Zhangjiajie (a rural area) in central south of China. Clinical examinations including ocular alignment, ocular motility, visual acuity (VA), prism cover test, cycloplegic refraction, slit lamp examination and fundus examination were performed by trained study ophthalmologists and optometrists. Unilateral amblyopia was defined as a 2-line difference between eyes with VA<20/32 in the worse eye and with coexisting anisometropia [≥1.00 D spherical eutivalent (SE) for hyperopia, ≥3.00 D SE for myopia, and ≥1.50 D for astigmatism], strabismus, or past or present visual axis obstruction. Bilateral amblyopia was defined as VA in both eyes <20/40 (≥ 48-month-old) and <20/50 (< 48-month-old), with coexisting hyperopia ≥4.00 D SE, myopia ≤-6.00 D SE, and astigmatism ≥2.50 D, or past or present visual axis obstruction. RESULTS: There were 8042 children enrolled and 7713 children were screened. The amblyopia prevalence in children aged 30-83mo was 1.09% (95% confidence interval, 0.86%-1.35%) with no age (P=0.81), gender (P=0.46) or area distribution (P=0.93) differences. Of these, 0.68% were unilateral cases and 0.41% were bilateral cases. Underlying causes included anisometropia (40%), binocular refractive error (36%), strabismus (14%) and deprivation (10%). Hyperopia combined with astigmatism was the frequent refractive error for ametropic and anisometropic amblyopia. CONCLUSION: In this rural and urban Chinese population, 1.09% of children with 30-83mo of age had amblyopia, a prevalence rate similar to that of many other studies. Anisometropia and refractive error are the most common causes of unilateral and bilateral amblyopia respectively.

Nitinol powders generate from Plasma Rotation Electrode Process provide clean powder for biomedical devices used with suitable size, spheroid surface and pure composition.

The nickel-titanium alloy (57Ni-43Ti in wt%) was atomized by the plasma rotating electrode process (PREP). The PREP parameters such as plasma arc current, rotating electrode speed with corresponding PREP powder size range in weight percentage analysis, powder morphology and biocapability of cells were studied by scanning electron microscopies, Inductively Coupled Plasma and X-ray diffraction techniques. From the electrode of the produced powders, the composition has no obviously changes. Weight percentage up to 31.8% of the range under 300 µm while the rotation electrode speed increase to 12k rpm. Spherical and flat with smooth surface were observed in different size range. Brittle phase was not observed of XRD data. The nitinol powder has high biocapability with cells showed no cytotoxicity and well cell adhesion in the in vivo assay.

Effects of microRNA-26b on proliferation and invasion of glioma cells and related mechanisms.

Neuroglioma is the most common primary malignant tumor in neurosurgery. Due to its short survival period and high patient mortality rate, neuroglioma is a major challenge in clinics. Elucidating the pathogenic mechanisms and associated molecular targets of neuroglioma can therefore benefit diagnosis and treatment of glioma. Previous studies have established the role of microRNA (miR)­26b in various tumors, including breast cancer, lymphoma and glioma. Its function and mechanism in neuroglioma, however, remains to be elucidated. In the present study, in vitro cultured U87 glioma cells were randomly divided into miR­26b mimic, miR­26b inhibitor and respective control (NC) groups. MTT assay was performed to detect the effect of miR­26b on cell proliferation, while a cell invasion assay detected its effects on cell invasion. Caspase­3 activity was also quantified to test cell apoptosis, followed by reverse transcription-quantitative polymerase chain reaction and western blotting to detect the variation of Bcl­2 expression under the effect of miR­26b. miR­26b mimics transfection upregulated its expression in U87 cells, which had significantly reduced Bcl­2 mRNA and protein expression levels and higher casapse3 activity, and inhibited cell proliferation and invasion compared with the control group. The transfection of miR­26b inhibitor, in contrast, facilitated U87 cell proliferation and invasion, inhibited caspase­3 activity and elevated Bcl­2 mRNA/protein expression. In conclusion, miR­26 could facilitate apoptosis and inhibit proliferation/invasion of neuroglioma cells via downregulating Bcl­2 expression and potentiating caspase-3 activity.

Novel lycorine derivatives as anticancer agents: synthesis and in vitro biological evaluation.

Lycorine, which is the most abundant alkaloid isolated from the Amaryllidaceae family of plants, reportedly exhibits promising anticancer activities. Herein, a series of novel lycorine derivatives were synthesized and evaluated for their in vitro inhibitory activities against seven different cancer cell lines, including A549, HCT116, SK-OV-3, NCI-H460, K562, MCF-7 and HL-60. The results indicated that compounds bearing diverse amine substituents at the C-2 position demonstrated good anticancer activities. The selectivity towards different cancer cell lines of the synthesized derivatives is discussed.

Leptin as a marker for severity and prognosis of aneurysmal subarachnoid hemorrhage.

Leptin has been identified as a plasma marker for outcomes in traumatic brain injury and intracerebral hemorrhage. We further investigated whether leptin might serve as a marker for severity and prognosis in aneurysmal subarachnoid hemorrhage. One hundred and eight consecutive patients and 108 sex and age - matched healthy subjects were recruited. Plasma leptin levels were measured by enzyme-linked immunosorbent assay. Clinical severity was assessed using World Federation of Neurological Surgeons score and Fisher score. Mortality and poor long-term outcome (Glasgow outcome scale scores of 1-3) at 6 months were recorded. Plasma leptin levels on admission were substantially higher in patients than in healthy controls, and were significantly associated with the clinical severity. There was also a significant association between leptin levels and clinical outcomes at 6 months in multivariate logistic regression analysis. Using receiver operating characteristic curves, we calculated areas under the curve for clinical outcomes at 6 months. The predictive performance of leptin was similar to, but did not obviously improve those of World Federation of Neurological Surgeons score and Fisher score. Thus, leptin may indicate clinical severity of the initial bleeding and also have prognostic value for clinical outcomes in aneurysmal subarachnoid hemorrhage and may therefore help in guiding treatment decisions in the setting of aneurysmal subarachnoid hemorrhage.

A new benzodioxocinone from the leaves of Cinnamomum tenuifolium.

Investigation of the leaves' extract of Cinnamomum tenuifolium (Lauraceae) led to the isolation of one novel benzodioxocinone, 2,3-dihydro-6,6-dimethylbenzo-[b][1,5]dioxocin-4(6 H)-one (1). The structure was determined through in-depth spectroscopic and mass-spectrometric analyses. The antioxidant potential was evaluated using the following in vitro method: scavenging of 1,1-diphenyl-2-picrylhydrazyl radical. We also detected the anti-proliferative effect of 1 on human oral cancer cells and its IC(50) is 107.7 µM.

Prognostic value of copeptin: one-year outcome in patients with traumatic brain injury.

High plasma copeptin level has been associated with one-month mortality after traumatic brain injury. However, not much is known regarding its relation with long-term outcome. Thus, we investigated the ability of copeptin to predict 1-year outcome in patients with traumatic brain injury. One hundred and six healthy controls and 106 patients with acute severe traumatic brain injury were included. Plasma samples were obtained on admission. Its concentration was measured by enzyme-linked immunosorbent assay. Forty-eight patients (45.3%) suffered from unfavorable outcome (Glasgow Outcome Scale score of 1-3) and 31 patients (29.2%) died in 1 year after traumatic brain injury. Upon admission, plasma copeptin level in patients was substantially higher than that in healthy controls. A forward stepwise logistic regression selected plasma copeptin level as an independent predictor for 1-year unfavorable outcome and mortality of patients. A receiver operating characteristic curve analysis showed plasma copeptin level predicted 1-year unfavorable outcome and mortality obviously. The predictive value of the copeptin concentration was thus similar to that of Glasgow Coma Scale score for the prediction of unfavorable outcome and mortality after 1 year. In a combined logistic-regression model, copeptin improved the area under curve of Glasgow Coma Scale score for the prediction of unfavorable outcome and mortality after 1 year, but the differences were not significant. Thus, copeptin level is a useful, complementary tool to predict functional outcome and mortality 1 year after traumatic brain injury.

[Controlled observation on cauterization with electric pyropuncture needle for treatment of body surface abscess].

OBJECTIVE: To probe and systematize the ancient cauterization with pyropuncture needle for evacuation of pus. METHODS: One hundred and eight cases of body surface abscess were randomly divided into 2 groups. The cauterization group (n=84) were treated by drainage with electric cauterization and the incision group (n=24) by drainage with incision. Clinical therapeutic effect, the healing time and the scar area of the wound were compared between the two groups. RESULTS: All of the patients in the two groups were effective with a similar therapeutic effect (P > 0.05); the cauterization group in the healing time and the scar area of the wound was superior to the incision group (P < 0.05). CONCLUSION: Electric cauterization for evacuation of pus has advantages of rapid healing and small scar area of wound.

Mechanism of ischemic tolerance induced by hyperbaric oxygen preconditioning involves upregulation of hypoxia-inducible factor-1alpha and erythropoietin in rats.

We studied the effect of hyperbaric oxygen (HBO) preconditioning on the molecular mechanisms of neuroprotection in a rat focal cerebral ischemic model. Seventy-two male Sprague-Dawley rats were pretreated with HBO (100% O(2), 2 atmospheres absolute, 1 h once every other day for 5 sessions) or with room air. In experiment 1, HBO-preconditioned rats and matched room air controls were subjected to focal cerebral ischemia or sham surgery. Postinjury motor parameters and infarction volumes of HBO-preconditioned rats were compared with those of controls. In experiment 2, HBO-preconditioned rats and matched room air controls were killed at different time points. Brain levels of hypoxia-inducible factor-1alpha (HIF-1alpha) and its downstream target gene erythropoietin (EPO) analyzed by Western blotting and RT-PCR as well as HIF-1alpha DNA-binding and transcriptional activities were determined in the ipsilateral hemisphere. HBO induced a marked increase in the protein expressions of HIF-1alpha and EPO and the activity of HIF-1alpha, as well as the expression of EPO mRNA. HBO preconditioning dramatically improved the neurobehavioral outcome at all time points (3.0 +/- 2.1 vs. 5.6 +/- 1.5 at 4 h, 5.0 +/- 1.8 vs. 8.8 +/- 1.4 at 8 h, 6.4 +/- 1.8 vs. 9.7 +/- 1.3 at 24 h; P < 0.01, respectively) and reduced infarction volumes (20.7 +/- 4.5 vs. 12.5 +/- 3.6%, 2,3,5-Triphenyltetrazolium chloride staining) after cerebral ischemia. This observation indicates that the neuroprotection induced by HBO preconditioning may be mediated by an upregulation of HIF-1alpha and its target gene EPO.

The endothelin receptor antagonist decreases ischemia/reperfusion-induced tumor necrosis factor production in isolated rat hearts.

Previous studies have shown that endothelin-1 (ET-1) may play a pathophysiological role in myocardial ischemia/reperfusion injury. In the present study, BMS-182874 significantly improved the recovery of cardiac function and reduced the release of CK during reperfusion after ischemia and the content of tumor necrosis factor (TNF-alpha) in myocardial tissues. BMS-182874 also reduced myocardial injury and the increased level of TNF-alpha by exogenous ET-1. These results suggest that the cardioprotective effects of the ET receptor antagonist may be related to inhibition of TNF-alpha production.

[Clinical features and surgical treatment of congenital ocular muscle palsy characterized with double elevator dysfunction].

OBJECTIVE: To investigate the clinical features of congenital ocular elevator muscle palsy and to evaluate the efficacy of surgical treatment. METHODS: Pre- and post-operative eye position, superior rectus muscle and inferior oblique muscle function, clinical features were examined and analyzed in 11 patients with congenital double elevator palsy of ocular muscles. RESULTS: When fixated with the nonparetic eye, ten of 11 patients showed hypotropia and pseudoblepharoptosis in the primary position; One of 11 patients fixated with the paretic eye and showed hypotropia in the primary position. All cases were a monocular elevation deficiency in abduction and adduction, and showed pseudoblepharoptosis. In ten patients fixated with the nonparetic eye, two of 10 were undergone inferior rectus recession on paretic eyes; six of 10 were undergone inferior rectus recession and superior oblique tenectomy on paretic eyes; two of 10 were applied inferior rectus recession and superior oblique tenectomy on paretic eyes, superior rectus recession was performed on healthy eyes in six months postoperation. The patient fixated with the paretic -eye were undergone superior rectus recession and inferior oblique tenectomy on healthy eyes. Seven patients with exotropia had lateral rectus muscle surgery performed at the time of their vertical operation. Strabismus were complete corrected in 81.8% (9/11) of patients in our study and 18.2% (2/11) of patients were partial corrected. The functions of superior rectus muscle and inferior oblique muscle were not corrected. Nine patients showed complete correction of the psuedoptosis, one patient showed partial correction of the psuedoptosis, one patient did not showed any improvement of the pseudoptosis. CONCLUSIONS: We conclude that superior rectus muscle and inferior oblique muscle insufficiency are the primary factors in the etiology of congenital double ocular elevator palsy. Vertical rectus recession and superior oblique tenectomy on paretic eyes is an effective way of surgical treatment the disease.