Upconversion nanoparticles/carbon dots (UCNPs@CDs) composite for simultaneous detection and speciation of divalent and trivalent iron ions.

In this study, the application of carbon dots (CDs) modified NaYF4:Yb, Er nanoparticles (UCNPs@CDs) as the fluorescent nanoprobe for simultaneous detection of Fe2+ and Fe3+ was investigated. Fe3+ quantification (5-80 µmol L-1) was achieved, as a result of Fe3+ induced fluorescence quenching of UCNPs@CDs at 434 nm (under the 336 nm excitation). The chelate (Fe2+-phen) formed by Fe2+ and 1,10-phenanthroline had a broad absorption centered at 510 nm, due to inner filter effect (IFE), Fe2+ quantification (4-120 µmol L-1) was achieved as a result of (Fe2+-phen) induced fluorescence quenching of UCNPs@CDs at 545 nm (under the 980 nm excitation). The resultant UCNPs@CDs probe, with excellent anti-interference capability, favorable fluorescence stability, and convincing performance in real sample analysis, showed promising application in simultaneous detection of Fe2+ and Fe3+.

GSK­3 inhibitor CHIR99021 enriches glioma stem­like cells.

Glioblastoma (GBM) is the most prevalent and lethal primary intrinsic brain cancer. The disease is essentially incurable, with glioblastomas characterized by resistance to both chemotherapy and radiotherapy, as well as by rapid tumor progression, all of which are mainly ascribed to glioma stem­like cells (GSLCs). In the present study, an improved model that is more similar to clinical GBM was constructed. Twenty clinical glioma samples were collected to obtain primary low­grade tumor cells. The cells were either maintained in serum­free medium as primary glioma­based cells (PGBCs) or cultured in the same medium with CHIR99021 as GSLCs. Then, the molecular and ultrastructural differences between the two cell groups were determined. Furthermore, the proliferation and migration of the GSLCs were examined and the potential mechanisms were investigated. Finally, temozolomide resistance in vitro and in the mouse model was assessed to study the properties of the induced GSLCs. The primary low­grade tumor cells extracted from surgical samples were enriched with GSLC properties, with high expression levels of CD133 and Nestin in 100 nM CHIR99021. The GSLCs exhibited high proliferation and migration. Furthermore, the expression of the PI3K/AKT signaling pathway and that of related genes and proteins were significantly enhanced by CHIR99021. The animal study also revealed high levels of STAT3, mTOR, NF­κB, and VEGF in the GSLC­transplanted mice. CHIR99021 could stably enhance GSLC properties in patient­derived glioma samples. It may provide a useful model for further study, helping to understand the pathogenesis of therapeutic resistance and to screen drug candidates.

Hybrid graphene/cadmium-free ZnSe/ZnS quantum dots phototransistors for UV detection.

Graphene-based optoelectronic devices have attracted much attention due to their broadband photon responsivity and fast response time. However, the performance of such graphene-based photodetectors is greatly limited by weak light absorption and low responsivity induced by the gapless nature of graphene. Here, we achieved a high responsivity above 103 AW-1 for Ultraviolet (UV) light in a hybrid structure based phototransistor, which consists of CVD-grown monolayer graphene and ZnSe/ZnS core/shell quantum dots. The photodetectors exhibit a selective photo responsivity for the UV light with the wavelength of 405 nm, confirming the main light absorption from QDs. The photo-generated charges have been found to transfer from QDs to graphene channel, leading to a gate-tunable photo responsivity with the maximum value obtained at V G about 15V. A recirculate 100 times behavior with a good stability of 21 days is demonstrated for our devices and another flexible graphene/QDs based photoconductors have been found to be functional after 1000 bending cycles. Such UV photodetectors based on graphene decorated with cadmium-free ZnSe/ZnS quantum dots offer a new way to build environmental friendly optoelectronics.

Ultrastructure of Pericystic or Intracystic Blood Vessels in Epidermoid Cysts-A Transmission Electron Microscopy Study: Laboratory Investigation.

OBJECTIVES: Recently, we reported a tendency toward spontaneous hemorrhage in both the preoperative and postoperative periods in patients with intracranial epidermoid cyst (EC). According to our experience, this tendency for spontaneous hemorrhage was partly caused by the pathologic blood vessels adjacent to the EC. This study was designed to testify this hypothesis. METHODS: Twenty-three removable pericystic or intracystic blood vessels from 17 patients with EC were collected during surgery and were then examined by transmission electron microscopy. The microvascular structure in gliomas was chosen as the control. RESULTS: Under electron microscopy, variant pathologic changes of vessels were found in all patients with EC. In the tunicae intima, we found vacuolization, apoptosis, necrosis, and intralumenal protrusion of endothelial cells, as well as swollen basement and highly flexed and discontinued elastic plate. In the tunicae media, vacuolization and swollen mitochondria were found in muscular cells. In the tunicae adventitia, extravascular erythrocytes, edema or apoptosis of pericytes, collagen predominance, and inflammatory cell infiltration and destruction were found. Neuron denature and necrosis were found in the peripheral brain tissue. In the microvascular structure of 5 glioma specimens, we found enlargement and hyperplasia of endothelial cells, swollen basement membrane, swollen pericytes, and astrocytic hyperplasia and neuron denature in adjacent brain tissues. CONCLUSIONS: Our findings provide strong evidence for the hypothesis that intracystic or pericystic vascular degeneration or destruction accounts for the spontaneous hemorrhage tendency before and after surgical resection of ECs.

Short-term Preoperative Octreotide for Thyrotropin-secreting Pituitary Adenoma.

BACKGROUND: Thyrotropin-secreting pituitary adenomas (TSHomas) are a rare cause of hyperthyroidism. Somatostatin (SST) analogs work by interacting with somatostatin receptors (SSTRs). This study aimed to evaluate short-term preoperative octreotide (OCT) use in TSHoma patients and to investigate SSTR2 and SSTR5 expression and observe structural changes in tumor tissue. METHODS: We reviewed records and samples from eight TSHoma patients treated between July 2012 and July 2015. We tested immunohistochemically for SSTR2/5 expression and examined TSHoma cells for morphological changes. Signed rank sum test was used to compare the efficacy of short-term preoperative OCT treatment. RESULTS: OCT treatment (median time: 7.9 days, range: 3-16 days; median total dose: 1.8 mg, range: 0.9-4.2 mg) led to significant decrease in all patients' thyroid hormone levels (FT3 [nmol/L]: 8.33 [7.02, 12.29] to 4.67 [3.52, 5.37] [P = 0.008]; FT4 [pmol/L]: 25.36 [21.34, 28.99] to 16.66 [14.88, 21.49] [P = 0.016]; and TSH [µU/ml]: 5.80 [4.37, 6.78] to 0.57 [0.19, 1.24] [P = 0.008]). All the eight tumor specimens expressed high SSTR2 protein levels; 5/8 expressed high SSTR5, but 3/8 that expressed low SSTR5 presented a significantly higher TSH suppression rate (P = 0.036). Electron microscopy showed subcellular level impairments, including clumped nuclear chromatin and reduced cytoplasmic volume. Golgi complexes were observed in the OCT-treated TSHoma specimens. CONCLUSIONS: OCT can control hormone levels and damage the ultrastructure of tumor cells and organelles. Short-term response to OCT may be related to SSTR5 expression. Preoperative SST analog treatment for TSHoma could be considered as a combination therapy.

Deletion of interleukin-6 alleviated interstitial fibrosis in streptozotocin-induced diabetic cardiomyopathy of mice through affecting TGFß1 and miR-29 pathways.

Interleukin 6 (IL-6) has been shown to be an important regulator of cardiac interstitial fibrosis. In this study, we explored the role of interleukin-6 in the development of diabetic cardiomyopathy and the underlying mechanisms. Cardiac function of IL-6 knockout mice was significantly improved and interstitial fibrosis was apparently alleviated in comparison with wildtype (WT) diabetic mice induced by streptozotocin (STZ). Treatment with IL-6 significantly promoted the proliferation and collagen production of cultured cardiac fibroblasts (CFs). High glucose treatment increased collagen production, which were mitigated in CFs from IL-6 KO mice. Moreover, IL-6 knockout alleviated the up-regulation of TGFß1 in diabetic hearts of mice and cultured CFs treated with high glucose or IL-6. Furthermore, the expression of miR-29 reduced upon IL-6 treatment, while increased in IL-6 KO hearts. Overexpression of miR-29 blocked the pro-fibrotic effects of IL-6 on cultured CFs. In summary, deletion of IL-6 is able to mitigate myocardial fibrosis and improve cardiac function of diabetic mice. The mechanism involves the regulation of IL-6 on TGFß1 and miR-29 pathway. This study indicates the therapeutic potential of IL-6 suppression on diabetic cardiomyopathy disease associated with fibrosis.

Diagnostic significance of intraoperative ultrasound contrast in evaluating the resection degree of brain glioma by transmission electron microscopic examination.

BACKGROUND: Contrast-enhanced ultrasound is a dynamic and continuous modality providing real-time view of vascularization and flow distribution patterns of different organs and tumors. In order to evaluate the diagnostic significance of intraoperative contrast-enhanced ultrasound in assessing the resection degree of brain glioma by transmission electron microscopic (TEM) examination, it is important to have specific knowledge about contrast-enhanced ultrasound. Methods : Ultrasound contrast was applied in operations of 120 cases of brain glioma, to evaluate the degree of tumor resection. Biopsy tissues were obtained the suspicious residual tumors surrounding the tumor cavity. The sensitivity and specificity of the residual tumors were determined by the intraoperative ultrasound contrast according to TEM examination results. RESULTS: There were 44 cases of low-grade gliomas and 76 cases of high-grade gliomas. Three hundred and sixty biopsy tissues were obtained. The sensitivity of intraoperative ultrasound contrast in diagnosing the residual tumor was 62.2%, while the specificity degree of it was 92.8%. The consistency coefficient of the ultrasound contrast diagnosis and TEM examination results was 0.584 (Kappa = 0.584), which was between 0.4 and 0.6, therefore it was of medium consistency. Conclusions : Intraoperative ultrasound contrast was of a high sensitivity and specificity in evaluating the excision degree of tumor. The consistency of the residual tumor rate detected, respectively, by ultrasound contrast and TEM examination was of medium consistency. The application of intraoperative ultrasound contrast can improve the resection rate of brain glioma.

Clinical and pathological analysis of benign brain tumors resected after Gamma Knife surgery.

OBJECT: The goal of this study was to assess the clinical and pathological features of benign brain tumors that had been treated with Gamma Knife surgery (GKS) followed by resection. METHODS: In this retrospective chart review, the authors identified 61 patients with intracranial benign tumors who had undergone neurosurgical intervention after GKS. Of these 61 patients, 27 were male and 34 were female; mean age was 49.1 years (range 19-73 years). There were 24 meningiomas, 18 schwannomas, 14 pituitary adenomas, 3 hemangioblastomas, and 2 craniopharyngiomas. The interval between GKS and craniotomy was 2-168 months, with a median of 24 months; for 7 patients, the interval was 10 years or longer. For 21 patients, a craniotomy was performed before and after GKS; in 9 patients, pathological specimens were obtained before and after GKS. A total of 29 patients underwent GKS at the Beijing Tiantan Hospital. All specimens obtained by surgical intervention underwent histopathological examination. RESULTS: Most patients underwent craniotomy because of tumor recurrence and/or exacerbation of clinical signs and symptoms. Neuroimaging analyses indicated tumor growth in 42 patients, hydrocephalus in 10 patients with vestibular schwannoma, cystic formation with mass effect in 7 patients, and tumor hemorrhage in 13 patients, of whom 10 had pituitary adenoma. Pathological examination demonstrated that, regardless of the type of tumor, GKS mainly induced coagulative necrosis of tumor parenchyma and stroma with some apoptosis and, ultimately, scar formation. In addition, irradiation induced vasculature stenosis and occlusion and tumor degeneration as a result of reduced blood supply. GKS-induced vasculature reaction was rarely observed in patients with pituitary adenoma. Pathological analysis of tumor specimens obtained before and after GKS did not indicate increased tumor proliferation after GKS. CONCLUSIONS: Radiosurgery is effective for intracranial benign tumors of small size and deep location and for tumor recurrence after surgical intervention; it is not effective for intracranial tumors with symptomatic mass effect. The radiobiological effects of stereotactic radiosurgery on the benign tumors are mainly caused by cellular and vascular mechanisms. Among the patients in this study, high-dose irradiation did not increase tumor proliferation. GKS can induce primary and secondary effects in tumors, which could last more than 10 years, thereby warranting long-term follow-up after GKS.

Severe pathological manifestation of cerebral amyloid angiopathy correlates with poor outcome from cerebral amyloid angiopathy related intracranial hemorrhage.

BACKGROUND: Cerebral amyloid angiopathy (CAA) is one of the main causes of spontaneous intracranial hemorrhage (ICH). No established link is available between pathological scores of CAA and its outcome. This study aimed to identify the correlations between pathological severity and poor postoperative outcome in the Chinese population. METHODS: Between May 2006 and April 2011, 367 consecutive patients who underwent surgery for CAA-related ICH in 71 hospitals throughout the mainland of China were enrolled in this study. Twelve months after surgery, we evaluated these patients' outcomes according to the modified Rankin Scale (mRS) and statistically correlated risk factors (demographics, medical history, pathological results, and surgical details) that are associated with a favorable (mRS < 3) and poor (mRS ≥ 3) outcome groups. RESULTS: Risk factors for poor postoperative outcome in 367 patients with CAA-related ICH included advanced age (OR 1.034, 95%CI 1.001 - 1.067, P = 0.042), CAA pathology severity (OR 2.074, 95%CI 7.140 - 16.25, P < 0.001), lobar hematoma (OR 0.225, 95%CI 0.104 - 0.486, P < 0.001), presence of intraventricular hemorrhage (OR 0.478, 95%CI 0.229 - 1.001, P = 0.050), and/or subarachnoid hemorrhage (OR 2.629, 95%CI, 1.051 - 6.577, P = 0.039). CONCLUSIONS: Poor postoperative outcome of patients with CAA-related ICH was more related to the severe pathological manifestation instead of other factors. Prior ischemia may present an early stage of CAA.

Clinical and histopathologic features of biofilm-associated chronic rhinosinusitis with nasal polyps in Chinese patients.

BACKGROUND: Biofilms have given new insights to the understanding of pathogenesis of chronic rhinosinusitis (CRS). However, the link between biofilms formation and local inflammatory response remains poorly defined in CRS with nasal polys. The aim of this study was to determine the potential association of the presence of biofilms in the nasal mucosal tissues with clinical features in Chinese patients, which had CRS with nasal polyps (CRSwNP). METHODS: A total of 19 patients with CRSwNP and 12 patients with non-CRS were subjected to endoscopic surgery and their nasal mucosal tissue specimens were examined histologically and by scanning electron microscopy (SEM). Their demographic and clinical features were recorded. RESULTS: Thirteen (68.4%) out of the 19 specimens from patients with CRSwNP, but none from control patients, were positive for biofilms that displayed typical characteristics of bacterial and fugal structures. The presence of biofilms in the nasal mucosal tissues was associated with significantly greater values of purulent nasal discharge and preoperative Lund-Kennedy scores, higher levels of serum total IgE and percentages of subjects with endoscopic surgery (ESS) history in patients with CRSwNP, and more severe inflammation in the nasal mucosal tissues of patients with CRSwNP. CONCLUSION: Our study demonstrated the presence of biofilms in the nasal mucosal tissues of many patients, contributing to the understanding of the pathogenic process of CRSwNP in Chinese patients.

[Clinical characteristics and ultra-structural features of skeletal muscle in mitochondrial cytopathies].

OBJECTIVE: To investigate the ultrastructural features of mitochondrial cytopathies and its diagnostic value. METHODS: Muscle biopsy specimens from 33 cases of mitochondrial cytopathies were examined by routine pathological and electron microscopic examinations. RESULTS: The main pathologic changes included ragged red fibers in modified Gomori staining, hyper-intense staining myofibers in SDH, COX-negative fibers while dark counterstaining with SDH in COX/SDH double staining technique. Ultrastructural findings included subsarcolemmal and intramyofibrillar proliferation of mitochondria and the appearance of abnormal mitochondria, paracrystalline inclusions, concentric dystrophic cristae and excessive subsarcolemmal glycolipid compounds in subsarcolemmal. CONCLUSION: The presence of proliferation and abnormality of mitochondria, electro-dense granule and paracrystalline inclusions in mitochondria provide key diagnostic evidence for the diagnosis of this disease.

[Clinical features of primary ciliary dyskinesia].

OBJECTIVE: To investigate the clinical features, diagnosis and treatment of primary ciliary dyskinesia (PCD). METHODS: Three cases of PCD received endoscopic sinus surgery and were followed up for life quality and recovery. Among these 3 cases, two were twin brothers and the other girl was twin born with a healthy brother. The mucosa of inferior turbinate was extracted prior to the operation without narcotic and decongestant. The ultrastructure of mucosal cilia was detected with electron microscope. Nine exons of gene DNAH5 and chromosome in one case and her fraternal twin were evaluated. RESULTS: Nasal and sinus CT imaging of the 3 cases showed chronic pansinusitis (1 case accompanied with situs inversus according with the diagnosis of Kartagener syndrome). The nasal polyp was resected, and the sinuses were opened. The twin brothers received the adenoidectomy. All patients felt nasal ventilation improved while the surgical field still covered with thick discharges during follow-up for 2 - 4 years. Ciliary ultrastructures of the three cases showed lateral dynein absent, the sequence of 9 exons of DNAH5 and chromosome presented no change in the fraternal twins. CONCLUSIONS: Surgery could improve the symptoms of sinusitis in PCD. Change of ciliary ultrastructure was an important indication of its pathological changes and molecular biology evaluation needs further study.

[Function magnetic resonance imaging and diffusion tensor tractography in patients with brain gliomas involving motor areas: clinical application and outcome].

OBJECTIVE: To explore the role of preoperative blood oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) and diffusion tensor tractography (DTT) to identify the relationship between motor cortical area, pyramidal tracts with brain gliomas in neurosurgical treatment of intraoperative electrical stimulation for gliomas involving motor areas at 3T. METHODS: Twenty-eight patients with brain gliomas involving motor areas were included. They underwent MRI examination, which included conventional T1WI, T2WI, BOLD-fMRI of bilateral hands movement paradigm and diffusion tensor imaging (DTI). The data of BOLD-fMRI and DTI were transferred to the workstation (Leonardo syngo 2003A, Siemens) and analyzed. Activation mapping of hands movement, fractional Anisotropy (FA) Color and three dimensional pyramidal tracts were produced. The relationship between motor cortical area, pyramidal tracts and brain gliomas was demonstrated, which was used to optimize the pre-surgical planning. With guidance of the result of BOLD-fMRI and DTT, all patients received microsurgery under anaesthesia retaining consciousness using intraoperative motor functional brain mapping with the method of direct electrical stimulations. The brain lesions were removed as far as possible in the case of eloquent areas and sub-cortical important white matters preservation. The preoperative and postoperative KPS of all patients were operated to evaluate the state of patients. RESULTS: BOLD-fMRI, DTI were performed successfully in 28 patients. The relationship between the primary motor cortex, premotor area, supplementary motor area, pyramidal tracts and brain gliomas localized by preoperative fMRI and DTI. Under anaesthesia retaining consciousness, the primary motor area was monitored by the method of direct electrical stimulations with the guidance of preoperative BOLD-fMRI. There was good correlation between preoperative fMRI and intraoperative cortical stimulation. Furthermore, the preoperative mappings and DTT could make up for the un-monitored motor areas and pyramidal tracts during operative cortical stimulation. Comparing the preoperative KPS, the postoperative KPS was advanced. CONCLUSIONS: BOLD-fMRI and DTT could non-invasively localize the relationship between brain motor cortex, pyramidal tracts and brain gliomas in vivo to optimize the surgical planning, guide the microsurgery under anaesthesia retaining consciousness using intraoperative motor functional brain mapping with the method of direct electrical stimulations and remove brain tumors as far as possible in the case of eloquent areas and sub-cortical important white matters preservation.

[In vitro study on inhibition of human choroidal melanoma OCM-1 cell line by arsenic trioxide].

OBJECTIVE: To investigate the effects and mechanisms of arsenic trioxide (ATO) on human choroidal melanoma cell line OCM-1. METHODS: OCM-1 cells were cultured with 0.75 to 24.00 micromol/L arsenic trioxide for various durations, then cell viability was measured by MTT assay. The cell necrosis and apoptosis rates were observed by flow cytometry. The morphological changes of the cells were examined by electron microscopy. Glutathione peroxidase (GSH-Px) activities were tested. Mitochondrial membrane potential (MMP) was detected by confocal microscopy. RESULTS: Growth of OCM-1 cells was inhibited by ATO at concentrations of (1.5 to 24.0) micromol/L. However, there was no effect of 0.75 micromol/L ATO on the growth of OCM-1 cells. The inhibition showed both dose and time dependent effects (P < 0.05). The IC(50) was 16.8 micromol/L at 24 h. Flow cytometry analysis showed a positive correlation between the rate of cell necrosis and apoptosis and the concentration of ATO. The cell necrosis rates were higher than the cell apoptosis rates at various concentrations of ATO. OCM-1 cells cultured with ATO showed the classic morphologic characteristics of necrosis and apoptosis. GSH-Px activities and MMP decreased in a dose dependent manner. CONCLUSION: ATO inhibits the growth of OCM-1 cells. The mechanism of this effect is that ATO inhibits the GSH-Px activities, decreases the MMP and impairs mitochondrial energy synthesis, which induces necrosis and apoptosis of human choroidal melanoma COM-1 cells eventually.

[Molecular mechanism of reversing metastatic phenotype in human high-metastatic large cell lung cancer cell line L9981 by nm23-H1].

BACKGROUND & OBJECTIVE: nm23-H1, a tumor metastasis suppressive gene, can reverse tumor metastasis phenotype. But the molecular mechanism of nm23-H1 in inhibiting or reversing metastasis of lung cancer is unclear. This study was to explore the molecular mechanism of nm23-H1 in reversing metastasis phenotype of lung cancer. METHODS: nm23-H1 gene and pLXSN were separately transfected into human lung cancer cell line L9981. Proliferation of L9981, L9981-pLXSN, and L9981-nm23-H1 cells was detected by MTT assay, cell invasive ability was detected by modified Boyden chamber. Tumorigenesis and experimental lung metastasis were determined in vivo. mRNA and protein levels of beta-catenin, E-Cadherin, CD44S, CD44V6, matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinase-1 (TIMP-1), and vascular endothelial growth factor (VEGF) were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. RESULTS: (1)Cell proliferation, clone formation, and invasive ability were significantly lower in L9981-nm23-H1 cells than in L9981 cells [(19.5+/-2.9)% vs. 100%, 10.3+/-0.7 vs. 21.7+/-1.3, 31.0+/-3.0 vs. 151.0+/-6.3, P<0.01]. (2) The inhibitory rate of tumorigenesis of nude mice was significantly higher in L8891-nm23-H1 group than in L9981 group (85.6% vs. 0%, P<0.001)u the lung metastatic rate was significantly lower in L9981-nm23-H1 group than in L9981 group (0% vs. 100%, P<0.001). (3)nm23-H1 up-regulated mRNA and protein levels of beta-catenin, E-Cadherin, and TIMP-1, and down-regulated levels of MMP-2, CD44V6, and VEGF (P<0.01). (4) nm23-H1 up-regulated mRNA level of CD44s, protein level of CD44s didn't change (P>0.05). CONCLUSION: nm23-H1 gene can reverse malignant and metastatic phenotype of L9981 cells through regulating the expressions of lung cancer metastasis-related genes.