Dynamic altruistic cooperation within breast tumors.

BACKGROUND: Social behaviors such as altruism, where one self-sacrifices for collective benefits, critically influence an organism's survival and responses to the environment. Such behaviors are widely exemplified in nature but have been underexplored in cancer cells which are conventionally seen as selfish competitive players. This multidisciplinary study explores altruism and its mechanism in breast cancer cells and its contribution to chemoresistance. METHODS: MicroRNA profiling was performed on circulating tumor cells collected from the blood of treated breast cancer patients. Cancer cell lines ectopically expressing candidate miRNA were used in co-culture experiments and treated with docetaxel. Ecological parameters like relative survival and relative fitness were assessed using flow cytometry. Functional studies and characterization performed in vitro and in vivo include proliferation, iTRAQ-mass spectrometry, RNA sequencing, inhibition by small molecules and antibodies, siRNA knockdown, CRISPR/dCas9 inhibition and fluorescence imaging of promoter reporter-expressing cells. Mathematical modeling based on evolutionary game theory was performed to simulate spatial organization of cancer cells. RESULTS: Opposing cancer processes underlie altruism: an oncogenic process involving secretion of IGFBP2 and CCL28 by the altruists to induce survival benefits in neighboring cells under taxane exposure, and a self-sacrificial tumor suppressive process impeding proliferation of altruists via cell cycle arrest. Both processes are regulated concurrently in the altruists by miR-125b, via differential NF-κB signaling specifically through IKKß. Altruistic cells persist in the tumor despite their self-sacrifice, as they can regenerate epigenetically from non-altruists via a KLF2/PCAF-mediated mechanism. The altruists maintain a sparse spatial organization by inhibiting surrounding cells from adopting the altruistic fate via a lateral inhibition mechanism involving a GAB1-PI3K-AKT-miR-125b signaling circuit. CONCLUSIONS: Our data reveal molecular mechanisms underlying manifestation, persistence and spatial spread of cancer cell altruism. A minor population behave altruistically at a cost to itself producing a collective benefit for the tumor, suggesting tumors to be dynamic social systems governed by the same rules of cooperation in social organisms. Understanding cancer cell altruism may lead to more holistic models of tumor evolution and drug response, as well as therapeutic paradigms that account for social interactions. Cancer cells constitute tractable experimental models for fields beyond oncology, like evolutionary ecology and game theory.

Influence of external insert angle on structural deformation of long pipe shed with shallow hole.

The long pipe shed advanced support has the characteristics of large construction difficulty, wide support range, and easy deviation. The difference in construction dip angle will produce a different plastic zone of surrounding rock and supporting effects, and the rationality of advanced support design plays an important role in the safety of tunnel opening excavation. Based on the Tianshan Tunnel project, this paper aims at the problems of the loose pebble layer structure, poor cohesion, strong permeability, shallow excavation is not easy to form a confined arch, and easy to causes surrounding rock deformation and failure. Combined with the new method theory, the finite difference software FLAC3D was used to simulate seven excavation schemes of the shallow tunnel entrances. The mechanism and effect of advance support and the influence of construction angle on support effect are analyzed, and the simulation values are compared with the measured data. The results show that using long pipe shed advanced support can effectively reduce the disturbance of excavation to lose pebble rock mass and reduce the convergence value of surrounding rock. The plastic zone of surrounding rock produced by different angles can be divided into three parts. The structural stability difference of the C1 zone is small, and that of the C3 zone is large. The bending moment, shear force, and shape variables of the pipe shed decrease with the increase of the dip angle, while the axial force increases with the increase of the dip angle. According to the similarity between the simulated curve and the measured curve, the best supporting effect can be achieved when the dip angle of the pre-supporting pipe shed is set in the range of 0° ~ 3°.

Alleviating experimental pulmonary hypertension via co-delivering FoxO1 stimulus and apoptosis activator to hyperproliferating pulmonary arteries

Pulmonary hypertension (PH) is an insidious pulmonary vasculopathy with high mortality and morbidity and its underlying pathogenesis is still poorly delineated. The hyperproliferation and apoptosis resistance of pulmonary artery smooth muscle cells (PASMCs) contributes to pulmonary vascular remodeling in pulmonary hypertension, which is closely linked to the downregulation of fork-head box transcriptional factor O1 (FoxO1) and apoptotic protein caspase 3 (Cas-3). Here, PA-targeted co-delivery of a FoxO1 stimulus (paclitaxel, PTX) and Cas-3 was exploited to alleviate monocrotaline-induced pulmonary hypertension. The co-delivery system is prepared by loading the active protein on paclitaxel-crystal nanoparticles, followed by a glucuronic acid coating to target the glucose transporter-1 on the PASMCs. The co-loaded system (170 nm) circulates in the blood over time, accumulates in the lung, effectively targets the PAs, and profoundly regresses the remodeling of pulmonary arteries and improves hemodynamics, leading to a decrease in pulmonary arterial pressure and Fulton's index. Our mechanistic studies suggest that the targeted co-delivery system alleviates experimental pulmonary hypertension primarily via the regression of PASMC proliferation by inhibiting cell cycle progression and promoting apoptosis. Taken together, this targeted co-delivery approach offers a promising avenue to target PAs and cure the intractable vasculopathy in pulmonary hypertension.

Knockdown of STIP1 inhibits the invasion of CD133­positive cancer stem­like cells of the osteosarcoma MG63 cell line via the PI3K/Akt and ERK1/2 pathways.

Osteosarcoma is the most common primary malignant tumor of the bone in adolescents and children, with high rates of metastasis and a poor prognosis. Recently, osteosarcoma cancer stem/stem­like cells (CSCs) have been identified as the main cause of recurrence and metastasis. Stress­induced phosphoprotein 1 (STIP1), a co­chaperone that binds to heat shock proteins 70 and 90, is abnormally expressed in several tumor cell lines, and may play an important role in tumor cell migration and invasion. These features indicate that STIP1 may represent a new therapeutic target for osteosarcoma CSCs. However, the role of STIP1 in osteosarcoma CSC migration and invasion remains largely unknown. In the present study, CD133­positive osteosarcoma CSCs were first isolated and cultured by magnetic cell sorting and serum­free medium suspension cell sphere culture, respectively. Knockdown of STIP1 by small interfering RNA significantly was then shown to inhibit the migration and invasion of these cells, possibly due to the regulation of the expression of matrix metalloproteinase (MMP)­2, MMP­9 and tissue inhibitor of metalloproteinase­2. Furthermore, data from the present study suggested that the knockdown of STIP1 decreased the levels of phosphorylated Akt and phosphorylated ERK1/2. In summary, these findings indicate that targeting STIP1 in osteosarcoma may constitute a viable molecular targeted therapy strategy for the inhibition of CSC invasion and migration.

Intracellular codelivery of anti-inflammatory drug and anti-miR 155 to treat inflammatory disease

Atherosclerosis (AS) is a lipid-driven chronic inflammatory disease occurring at the arterial subendothelial space. Macrophages play a critical role in the initiation and development of AS. Herein, targeted codelivery of anti-miR 155 and anti-inflammatory baicalein is exploited to polarize macrophages toward M2 phenotype, inhibit inflammation and treat AS. The codelivery system consists of a carrier-free strategy (drug-delivering-drug, DDD), fabricated by loading anti-miR155 on baicalein nanocrystals, named as baicalein nanorods (BNRs), followed by sialic acid coating to target macrophages. The codelivery system, with a diameter of 150 nm, enables efficient intracellular delivery of anti-miR155 and polarizes M1 to M2, while markedly lowers the level of inflammatory factors and . In particular, intracellular fate assay reveals that the codelivery system allows for sustained drug release over time after internalization. Moreover, due to prolonged blood circulation and improved accumulation at the AS plaque, the codelivery system significantly alleviates AS in animal model by increasing the artery lumen diameter, reducing blood pressure, promoting M2 polarization, inhibiting secretion of inflammatory factors and decreasing blood lipids. Taken together, the codelivery could potentially be used to treat vascular inflammation.

A novel and validated nomogram to predict overall survival for gastric neuroendocrine neoplasms.

BACKGROUND: This study aims to develop and validate an effective nomogram to estimate the individual outcome of patients with Gastric neuroendocrine neoplasms (G-NENs). METHODS: A total of 260 patients diagnosed with G-NENs at two medical centers were included, with 156 patients allocated as training set and 104 patients as validation. Predictive nomogram was constructed based on multivariate analyses using RMS package in R version. The predictive accuracy and discriminative ability were analyzed by C-index, risk group stratification and calibration curve, which was compared with other predictive systems for G-NENs. RESULTS: In multivariate analysis, age, Ki-67, mitoses, neutrophil to lymphocyte ratio, serum tumor marker and distant metastasis were significantly associated with overall survival. The constructed prognostic nomogram demonstrated a good calibration and discrimination value with 0.884 and 0.852 C-indices in training and validation dataset. Compare to World Health Organization (WHO) grading system (C-indices=0.760 and 0.732) and American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) staging system (C-indices=0.747 and 0.811), the nomogram displayed a better predictive accuracy. CONCLUSIONS: The novel prognostic nomogram showed superior predictive value in overall survival of G-NENs. It might be a useful tool for clinicians in estimating individual survival in G-NENs patients.

All-Solution-Processed Red and Orange-Red Organic Light-Emitting Diodes with High-Efficiencies: The Effect of Mixed-Host Emissive Layers and Thermal Annealing Treatment.

The instability of the organic light-emitting diodes (OLEDs) during operation can be attributed to the existence of point defects on the organic layers. In this work, the effect of mixed-host emissive layer and the thermal annealing treatment were investigated to eliminate defects and to boost the device performance. The mixed-host system includes 4,4',4''-tri (9-carbazoyl) triphenylamine (TCTA) and 2,7-bis(diphenylphosphoryl)-9, 9'-spirobi[fluorene] (SPPO13). The mixed-host emissive layer with thermal annealing treatment showed low roughness and few pinholes, and the devices fabricated from this emissive layer exhibited high efficiencies, high stabilities, and long lifetimes. The red and orange-red OLEDs exhibited efficiencies of 13.9 cd/A and 24.35 cd/A, respectively. The longest half-lifetime (L0 =500 cd/m2 ) of the red and orange-red OLEDs were 158 h and 180 h, respectively. Efforts were made to solve problems in large-area coating and to reduce the number of defects on in organic layer. Large-active-area (active area=3 cm×4 cm) red phosphorescent OLEDs (PhOLEDs) devices were realized with very high current efficiency up to 9 cd/A.

The prognostic role of Gas6/Axl axis in solid malignancies: a meta-analysis and literature review.

BACKGROUND: Axl is a receptor tyrosine kinase that is involved in many pathological conditions and carcinogenesis. Gas6 is the major ligand of Axl. Activation of Gas6/Axl pathway is essential for cancer development. However, its prognostic significance in solid tumors remains unclear. Therefore, we performed this meta-analysis to elucidate the prognostic impact of Axl. METHODS: Published studies on Axl or Gas6 expression and overall survival (OS) and/or disease-free survival (DFS) were searched from databases. The outcome measurement is hazard ratio (HR) for OS or DFS related to Axl/Gas6 expression. Meta-analysis was performed using RevMan. The pooled HR was calculated by fixed-/random-effect models. RESULTS: A total of 3,344 patients from 25 studies were included. The results of meta-analysis showed that Axl overexpression was correlated with shorter OS (HR: 2.03, p<0.0001) and DFS (HR: 1.85, p<0.0001). In subgroup analysis, Axl expression was significantly correlated with poor prognosis in hepatocellular, esophageal and lung cancer. Axl expression was associated with differentiation grade, TNM stage, lymph node and distant metastasis. CONCLUSION: These results suggest that Axl overexpression is correlated with poor prognosis in solid tumors. This correlation varies among different types of cancers. More studies are needed to further investigate the prognostic value of Axl.

Prognostic significance of SATB1 in gastrointestinal cancer: a meta-analysis and literature review.

BACKGROUND: The special AT-rich sequence-binding proteins 1 (SATB1) is a major regulator involved in cell differentiation. It has been shown that SATB1 acts as an oncogenic regulator. The clinical and prognostic significance of SATB1 in gastrointestinal cancer remains controversial. The purpose of this study is to conduct a systematic review and meta-analysis to elucidate the impact of SATB1 in gastrointestinal cancer. RESULTS: A total of 3174 gastrointestinal cancer patients from 15 studies were included. The correlation between SATB1 expression and OS or RFS was investigated in 12 and 5 studies respectively. The results of meta-analysis showed that SATB1 overexpression is inversely correlated with OS (combined HR: 1.79, p = 0.0003) and RFS (combined HR: 2.46, p < 0.0001). In subgroup analysis, SATB1 expression is significantly correlated with poor prognosis in gastrointestinal cancer in Asian population. SATB1 expression is associated with stage, invasion depth, lymph node metastasis and distant metastasis. METHODOLOGY: Published studies with data on overall survival (OS) and/or relapse free survival (RFS) and SATB1 expression were searched from Cochrane Library, PubMed and Embase (up to Dec 30, 2016). The outcome measurement is hazard ratio (HR) for OS or RFS related with SATB1 expression. Two reviewers independently screened the literatures, extracted the data and performed meta-analysis using RevMan 5.3.0 software. The combined HRs were calculated by fixed- or random-effect models. CONCLUSIONS: The results of this meta-analysis suggest that SATB1 overexpression is related to advanced stage, lymph node metastasis and distant metastasis. SATB1 overexpression is a marker indicating poor prognosis in gastrointestinal cancer.

Application value of standard curve of K+ concentration in dialysis solution in personalized dialysis therapy / 医疗卫生装备

Objective To investigate the linear relationship and standard curve equation between acidic concentrated solution added KCl and the changes of K+ concentration in dialysate,and to apply it in personalized dialysis.Methods The speed of concentrated liquid pump of Fresenius 4008S hemodialysis machine was calibrated,the ratio of the concentration solution to the reverse osmosis water was determined,KCl was added to the concentrated A solution by an equal increment method to detect K+ concentration in the corresponding dialysate,and the K+ concentration standard curve of dialysate was mapped.This study is based on blood K+ concentration of adams-stokes syndrome patients before dialysis,referring to the standard curve,the most suitable dialysate K+ concentration was selected to personalized dialysis,the blood K+ concentration of the patients was measured after dialysis,and ECG monitoring and clinical symptoms observation were carried out.Results There was a linear relationship between acidic concentrated solution added KCl and the changes of K+ concentration in dialysate,the curve equation was y =0.384 lx + 0.002 3,R2 =0.999 4.There was no obvious change in the concentration of other electrolyte ions in the dialysate.Referring to the standard curve,the concentration of dialysate K+ could be adjusted accurately.The blood K+ concentration of adams-stokes syndrome patients could be corrected in time after several times of K+ concentration of personalized dialysis,and ECG recovered eventually,and arrhythmia,syncope,chest tightness and other symptoms disappeared.Conclusion There is a linear relationship between the concentration of dialysate K + and the concentration of KCl added in acidic concentrated solution in the Fresenius 4008S hemodialysis machine.Personalized dialysis is performed by the standard curve with obvious clinical application value,and references are provided for precise regulation of dialysate ion concentration.

Application value of standard curve of K+ concentration in dialysis solution in personalized dialysis therapy / 医疗卫生装备

Objective To investigate the linear relationship and standard curve equation between acidic concentrated solution added KCl and the changes of K+ concentration in dialysate,and to apply it in personalized dialysis.Methods The speed of concentrated liquid pump of Fresenius 4008S hemodialysis machine was calibrated,the ratio of the concentration solution to the reverse osmosis water was determined,KCl was added to the concentrated A solution by an equal increment method to detect K+ concentration in the corresponding dialysate,and the K+ concentration standard curve of dialysate was mapped.This study is based on blood K+ concentration of adams-stokes syndrome patients before dialysis,referring to the standard curve,the most suitable dialysate K+ concentration was selected to personalized dialysis,the blood K+ concentration of the patients was measured after dialysis,and ECG monitoring and clinical symptoms observation were carried out.Results There was a linear relationship between acidic concentrated solution added KCl and the changes of K+ concentration in dialysate,the curve equation was y =0.384 lx + 0.002 3,R2 =0.999 4.There was no obvious change in the concentration of other electrolyte ions in the dialysate.Referring to the standard curve,the concentration of dialysate K+ could be adjusted accurately.The blood K+ concentration of adams-stokes syndrome patients could be corrected in time after several times of K+ concentration of personalized dialysis,and ECG recovered eventually,and arrhythmia,syncope,chest tightness and other symptoms disappeared.Conclusion There is a linear relationship between the concentration of dialysate K + and the concentration of KCl added in acidic concentrated solution in the Fresenius 4008S hemodialysis machine.Personalized dialysis is performed by the standard curve with obvious clinical application value,and references are provided for precise regulation of dialysate ion concentration.

MiR-21 mediates the radiation resistance of glioblastoma cells by regulating PDCD4 and hMSH2.

The purpose of this study was to investigate the molecular mechanism by which miR-21 and its target genes mediate radiation resistance of glioblastoma cells. Real-time PCR was employed to detect miR-21 expression in normal brain tissues, glioblastoma tissues and glioblastoma cell lines (A172, T98G and U87MG). T98G cells were transfected with anti-miR-21 oligonucleotides, or plasmids containing PDCD4 or hMSH2 (PDCD4-pcDNA3 and hMSH2-pcDNA3). The survival curve was obtained to investigate the sensitivity of T98G cells to radiation. Cell apoptosis was measured by using the Caspase-3/7 kit and cell cycle by flow cytometry. Western blotting was performed to detect the expression of hMSH2 and PDCD4 in miR-21-inhibiting T98G cells. The results showed that miR-21 expression in glioblastoma cells and tissues was conversely associated with the radiation sensitivity. Over-expression of miR-21 resulted in radiation resistance, while knockdown of miR-21 led to higher sensitivity of glioblastma cells to radiation. After miR-21 knockdown, the apoptosis of T98G cells was significantly increased and the G(2) phase arrest was more significant. In addition, miR-21 knockdown increased the expression of endogenous PDCD4 and hMSH2, which contributed to the apoptosis and G(2) arrest of T98G cells. The findings suggested that miR-21 may mediate the resistance of glioblastoma cells against radiation via its target genes PDCD4 and hMSH2. MiR-21 and its target genes may be used as potential molecular targets for clinical radiotherapy sensitization in the future.

Identification of differentially expressed microRNAs by microarray: a possible role for microRNAs gene in medulloblastomas.

BACKGROUND: MicroRNAs (miRNAs) are small noncoding regulatory RNAs whose aberrant expression may be observed in many malignancies. However, few data are yet available on human primary medulloblastomas. This work aimed to identify that whether miRNAs would be aberrantly expressed in tumor tissues compared with non-tumorous cerebellum tissues from same patients, and to explore a possible role during carcinogenesis. METHODS: A high throughput microRNA microarray was performed in human primary medulloblastoma specimens to investigate differentially expressed miRNAs, and some miRNAs were validated using real-time quantitative RT-PCR method. In addition, the predicted target genes for the most significantly down- or up-regulated miRNAs were analyzed by using a newly modified ensemble algorithm. RESULTS: Nine miRNA species were differentially expressed in medulloblastoma specimens versus normal non-tumorous cerebellum tissues. Of these, 4 were over expressed and 5 were under expressed. The changes ranged from 0.02-fold to 6.61-fold. These findings were confirmed using real-time quantitative RT-PCR for most significant deregulated miRNAs (miR-17, miR-100, miR-106b, and miR-218) which are novel and have not been previously published. Interestingly, most of the predicted target genes for these miRNAs were involved in medulloblastoma carcinogenesis. CONCLUSIONS: MiRNAs are differentially expressed between human medulloblastoma and non-tumorous cerebellum tissue. MiRNAs may play a role in the tumorigenesis of medulloblastoma and maybe serve as potential targets for novel therapeutic strategies in future.

Low-bandgap poly(thiophene-phenylene-thiophene) derivatives with broaden absorption spectra for use in high-performance bulk-heterojunction polymer solar cells.

Two low-bandgap (LGB) conjugated polymers ( P1 and P2) based on thiophene-phenylene-thiophene (TPT) with adequate energy levels have been designed and synthesized for application in bulk-heterojunction polymer solar cells (PSCs). The absorption spectral, electrochemical, field effect hole mobility and photovoltaic properties of LGB TPT derivatives are investigated and compared with poly(3-hexylthiophene) (P3HT). Photophysical studies reveal bandgaps of 1.76 eV for P1 and 1.70 eV for P2, which could effectively harvest broader solar spectrum. In addition, the thin film absorption coefficients of P1 and P2 are 1.6 x 10 (5) cm (-1) (lambda approximately 520 nm) and 1.4 x 10 (5) cm (-1) (lambda approximately 590 nm), respectively. Electrochemical studies indicate desirable HOMO/LUMO levels that enable a high open circuit voltage while blending them with fullerene derivatives as electron acceptors. Furthermore, both materials show sufficient hole mobility (3.4 x 10 (-3) cm (2)/Vs for P2) allowing efficient charge extraction and a good fill-factor for PSC application. High-performance power conversion efficiency (PCE) of 4.4% is obtained under simulated solar light AM 1.5 G (100 mW/cm (2)) from PSC device with an active layer containing 25 wt% P2 and 75 wt% [6,6]-phenyl-C71-butyric acid methyl ester (PC 71BM), which is superior to that of the analogous P3HT cell (3.9%) under the same experimental condition.

[MiR-9 regulates the expression of CBX7 in human glioma].

OBJECTIVE: To detect the expression of CBX7 in human glioma and investigate the potential regulatory effect of abnormally expressed microRNAs on CBX7 expression. METHODS: Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western blot were applied to detect the expression pattern of CBX7 in 2 human normal brain tissues, 9 glioma tissues, and 3 glioma cell lines. Miranda algorithm and Ensemble Machine Learning algorithm were combined to predict miRNAs that target human CBX7. The expression of miR-9 in those tissues and cell lines were detected by real-time PCR. After miR-9 overexpression in 293ET and miR-9 knock-down in T98G, luciferase assay and Western blot were used to confirm the effect of miR-9 on CBX7 expression. MTT assay and flow cytometry were applied to detect the effect of miR-9 knock-down on T98G cells. RESULTS: No obvious difference in the CBX7 mRNA level between normal and tumor tissues was observed, while the protein level of CBX7 was abrogated or markedly reduced in glioma tissues and cell lines. Several miRNAs including miR-9 may target CBX7 by bioinformatics prediction. MiR-9 was up-regulated in glioma tissues and cell lines. In 293ET cell, luciferase activity of CBX7-3'UTR reporter was decreased to 24% after miR-9 overexpression. After miR-9 knock-down in T98G cell, the luciferase activity was increased by 1.8 fold and there was no change of CBX7 mRNA, while the protein level of endogenous CBX7 was significantly increased. The number of survival T98G cells increased and cells in G1 phase decreased after miR-9 knock-down. CONCLUSION: In human glioma, CBX7 is down-regulated by the inhibition of miR-9 at posttranscriptional level.

Direct measurements of intersystem crossing rates and triplet decays of luminescent conjugated oligomers in solutions.

Photothermal calorimetry and fluorescence spectroscopy were used to determine the relaxations of the photoexcited singlet state of two PPV and polyfluorene oligomers, (E,E)-1,4-bis[(2-benzyloxy)styryl]benzene (PVDOP) and ter(9,9'-spirobifluorene) (TSBF). The decay rates of different S1 relaxation channels, which include intersystem crossing (ISC), radiative, and nonradiative decay can be determined by the combination of photoacoustic calorimetry (PAC) and the time-correlated single photon counting (TCSPC) technique. The triplet state energy level is determined by the phosphorescence (Ph) spectra recorded at 77 K. The ISC yields are approximately 3% and 6% for PVDOP and TSBF, respectively. The T1 to S0 transition decay rate is acquired by PAC and photothermal beam deflection (PBD) measurements. The triplet state decay rate is 17 and 21 ms(-1) at room temperature. The Ph intensity decay at 77 K shows that the triplet state lifetime increases by 4 orders of magnitude, as compared to room temperature.

Correlation of brain hypoxia at different degrees with brain function and brain damage investigated using near infrared spectroscopy / 中华儿科杂志

<p><b>OBJECTIVE</b>To study correlation of brain hypoxia of different degrees with brain function and damage.</p><p><b>METHODS</b>The brain regional oxygen saturation (rSO2) was determined by using a non-invasive near infrared spectroscopy (NIRS) technique in 15 piglets; the piglets were subjected to inhale 3% - 11% oxygen-nitrogen mixed gas through mechanical ventilation for 30 min. The piglets were divided into groups according to the level of brain rSO2 (i.e. < 30%, 30% - 35%, 35% - 40%, and 40% - 50%), and the data were compared with those of the control group (rSO2 > 60%). Changes of brain function were detected through amplitude and frequency of EEG waves and signal complexity. The piglets were sacrificed via decapitation 72 h after brain damage, and then histopathological and ultrastructural examinations were performed on cerebral cortex and hippocampal CA1 area.</p><p><b>RESULTS</b>In the group with rSO2 > 40%, the mean arterial pressure (MAP) after hypoxia was (56 +/- 0.00) mm Hg (1 mm Hg = 0.133 kPa), the blood lactic acid (LA) was (2.3 +/- 1.2) mmol/L, the EEG findings were within normal range, and there was no change in brain tissue ultrastructure. In the group with brain rSO2 = 30% approximately 40%, the MAP was (73 +/- 8) mm Hg, the LA was (8.2 +/- 3.9) mmol/L, the EEG waves showed decreased amplitude, frequency and complexity, but restored to some extent after hypoxia. The brain tissue ultrastructure showed damages to the cerebral cortex and neuron mitochondria at hippocampal CA1 area. In the group with brain rSO2 < 30%, the MAP was (35 +/- 0) mm Hg, the LA was (12 +/- 2) mmol/L, the EEG showed decreased amplitude, frequency, and complexity of signals compared with those of the normal control group, and was difficult to restore after hypoxia in some of the piglets; the brain tissue ultrastructure appeared to be similar to the changes seen with high-degree swollen cerebral cortex and neuron mitochondria at hippocampal CA1 area.</p><p><b>CONCLUSION</b>Different degrees of hypoxia had different influence on brain function and brain damage. The lower the brain rSO2, the more severe the damages to the brain and its function. The rSO2 of brain tissues detected with noninvasive NIRS can reflect brain injury and its severity during cerebral anoxia.</p>

Syntheses and structures of novel heteroarene-fused coplanar pi-conjugated chromophores.

We have synthesized a series of novel coplanar chromophores in which heteroarenes, namely, thiophene, benzothiophene, and carbazole, were fused to neighboring phenylene ring(s) through intramolecular annulation via sp(3)-hybridized carbon atoms bearing two p-tolyl groups as peripheral substituents. The molecular configurations of the pi-conjugated backbones were determined by X-ray crystallographic analysis; the heteroarene-fused molecular frameworks of these novel molecules exhibit nearly coplanar conformations. [structure: see text]

Modulation of physical properties of Ter(9,9-ditolylfluorene) by backbone-embedded heteroarenes.

[structure: see text] Novel ter(9,9-ditolylfluorene) analogues containing thiophene and pyridine rings embedded as functional constituents within the parent hydrocarbon backbone have been synthesized. These new molecules exhibit highly efficient photoluminescence and high thermal and morphological stability. The electronic structure of the terfluorene backbone is significantly perturbed, which allows modulation of the backbone energy levels.