Self-Assembling Nonconjugated Poly(amide-imide) into Thermoresponsive Nanovesicles with Unexpected Red Fluorescence for Bioimaging.

Nonconjugated red fluorescent polymers have been increasingly studied to improve the biocompatibility and penetration depth over conventional fluorescent materials. However, the accessibility of such polymers remains challenging due to the scarcity of nonconjugated fluorophores and lacking relevant mechanism of red-shifted fluorescence. Herein, we discovered that the combination of hydrogen bonding and π-π stacking interactions provides nonconjugated poly(amide-imide) with a large bathochromic shift (>100 nm) from blue-green fluorescence to red emission. The amphiphilic PEGylated poly(amide-imide) derived from in situ PEGylation self-assembled into nanovesicles in water, which isolated the aminosuccinimide fluorophore from the solvents and suppressed the hydrogen bonds formation between aminosuccinimide fluorophores and water. Therefore, the fluorescence of PEGylated poly(amide-imide) in water was soundly retained. Furthermore, the strong hydrogen bonding and hydrophobic interactions with water provided PEGylated poly(amide-imide) with a reversible thermoresponsiveness and presented a concentration-dependent behavior. Finally, accompanied by the excellent biostability and photostability, PEGylated poly(amide-imide) exhibited as a good candidate for cell imaging.

GGPPS, a new EGR-1 target gene, reactivates ERK 1/2 signaling through increasing Ras prenylation.

Cigarette smoke activates the extracellular signal-regulated kinase (ERK) 1/2 mitogen activated-protein kinase pathway, which, in turn, is responsible for early growth response gene-1 (EGR-1) activation. Here we provide evidence that EGR-1 activation can also reactivate ERK 1/2 mitogen activated-protein kinase through a positive feedback loop through its target gene (geranylgeranyl diphosphate synthase) GGPPS. For the first time, the GGPPS gene is identified as a target of EGR-1, as EGR-1 can directly bind to the predicted consensus-binding site in the GGPPS promoter and regulate its transcription. Long-term observations show that there are two ERK 1/2 phosphorylation peaks after cigarette smoke extract stimulation in human lung epithelial Beas-2B cells. The first peak (at 10 minutes) is responsible for EGR-1 accumulation, and the second (at 4 hours) is diminished after the disruption of EGR-1 transcriptional activity. EGR-1 overexpression enhances Ras prenylation and membrane association in a GGPPS-dependent manner, and it augments ERK 1/2 activation. Likewise, a great reduction of the second peak of ERK 1/2 phosphorylation is observed during long-term cigarette smoke extract stimulation in cells where GGPPS is disrupted. Thus, we have uncovered an intricate positive feedback loop in which ERK 1/2-activated EGR-1 promotes ERK 1/2 reactivation through promoting GGPPS transcription, which might affect cigarette smoke-related lung pathological processes.

Cigarette smoke-induced pulmonary inflammatory responses are mediated by EGR-1/GGPPS/MAPK signaling.

Early growth response 1 (EGR-1) contributes to the development of chronic obstructive pulmonary disease in the lungs of smokers by mediating pulmonary inflammatory responses, but the direct downstream genes of EGR-1 that regulate this process remain unknown. We show that a new EGR-1 target gene, geranylgeranyl diphosphate synthase (GGPPS), which controls protein prenylation, can regulate the proinflammatory function of EGR-1 by activating MAPK signaling. When C57BL/6 mice were exposed to cigarette smoke, EGR-1 and GGPPS levels increased in their lungs, and the inflammatory responses were augmented, whereas these effects could be reversed by the down-regulation of EGR-1 transcription activity. The accumulation of EGR-1 and GGPPS was induced by MAPK/ERK pathway activation when Beas-2B human bronchial epithelial cells were exposed to cigarette smoke extract (CSE). Further examination showed that EGR-1 in turn regulated Erk1/2 activity because inhibition of EGR-1 transcription activity decreased CSE-induced Erk1/2 phosphorylation. Furthermore, EGR-1-promoted Erk1/2 activation was dependent on GGPPS transcription. Knockdown of GGPPS expression with small-interfering RNA abolished the EGR-1-activated Erk1/2 activity. Both EGR-1 transcription inhibition and GGPPS expression knockdown decreased the inflammatory response induced by CSE in Beas-2B cells. Our results reveal a new EGR-1/GGPPS/MAPK signaling pathway that controls cigarette smoke-induced pulmonary inflammation, and this may shed light on our understanding of the mechanism of cigarette smoke-related pulmonary diseases such as chronic obstructive pulmonary disease.

Cardiorespiratory arrest after iso-osmolar iodinated contrast injection: A case report of contrast-induced encephalopathy following contrast-enhanced computed-tomography.

RATIONALE: Contrast-induced encephalopathy (CIE) is a rare complication caused by administration of intravascular contrast media and characterized by acute reversible neurological disturbance. Most of the CIE cases are reported after arterial administration of contrast media such as during cerebral or coronary angiographies, yet only a few articles have reported CIE secondary to intravenous contrast. A case of CIE secondary to intravenous contrast administration is reported here. PATIENT CONCERNS: A 68-year-old man was admitted to our hospital for contrast-enhanced chest computed-tomography (CT) examination due to suspected pulmonary nodules. After CT examination, the patient lost consciousness and experienced a cardiorespiratory arrest. An emergency plain brain CT was done immediately which showed abnormal cortical contrast enhancement and cerebral sulci hyperdensity. DIAGNOSES: After excluding other differential diagnoses such as electrolytes imbalance, hypo/hyperglycemia, cardiogenic pathologies and other neurological emergencies such as cerebral hemorrhage, cerebral infarction, the final diagnosis of CIE was made. INTERVENTIONS: The patient was admitted to the intensive care unit for further management. A series of supportive treatments were arranged. OUTCOMES: Follow-up visits at the outpatient clinic showed no lasting neurological deficits. LESSONS: CIE should be considered as 1 of the differential diagnoses for a patient with acute neurologic symptoms after iodinate contrast administration. Neuroradiological imaging examinations are essential to rule out other etiologies such as acute cerebral infarction or intracranial hemorrhage.

Primary thoracic neuroblastoma in an adult: A rare case report.

RATIONALE: Neuroblastoma is one of the most common malignant tumors in childhood, which mainly occurs in adrenal glands and peripheral sympathetic nerve system. Neuroblastoma occurring in adulthood is rare, and adults with neuroblastoma arising from thorax are exceedingly rare. A case of neuroblastoma that originated from thorax was reported, and was treated by resection operation. PATIENT CONCERNS: A 46-year-old woman was admitted to our hospital with left side chest pain for 5 days. Laboratory examinations were all normal. Chest computerized tomogram (CT) showed a lesion with clear boundary that was located at the left dorsal pleura. The nature of the mass was heterogeneous, showing slight heterogeneous enhancement after contrast and there was no obvious necrosis. DIAGNOSES: Based on the morphologic and immunohistochemical features, the tumor diagnosis was favorable for neuroblastoma. INTERVENTIONS: A resection operation was carried out. OUTCOMES: Three years postoperative, no sign of recurrence or metastasis has been observed. LESSONS: Primary neuroblastoma in adulthood is rare and has poor prognosis. Resection can be an important treatment option, and combining with other methods like chemotherapy, stem cell transplantation, the survival rate may be improved.

Aberrant expression and function of TCF4 in the proliferation of hepatocellular carcinoma cell line BEL-7402.

Wnt signaling pathway is essential for development and tumorigenesis, however, this signaling pathway in the progress of hepatocellular carcinoma (HCC) remains unclear. In this paper, we studied the function of human T-cell transcription factor-4 (TCF4), a key factor of Wnt signaling pathway, on the proliferation of HCC cell line. We showed that the expression of TCF4 mRNA in HCC cell line BEL-7402 was higher than that in immortalized normal liver cell line L02. Blockage of Wnt pathway by Delta-NTCF4, a dominant negative TCF4, could suppress BEL-7402 cells growth and decrease the expression of cyclin D1 and c-myc, two of target genes of Wnt pathway. On the other hand, stimulating Wnt pathway by introducing a degradation-resistant -catenin S37A could increase BEL-7402 cells proliferation. But all the treatments had no effect on L02 cells. Our data indicated that TCF4 might be another key factor in Wnt pathway involved in HCC cells proliferation and TCF4 could be an effective therapeutic target for suppressing the growth of hepatocellular cancers.

Overexpression of Fc receptor-like 1 associated with B-cell activation during hepatitis B virus infection.

The role of B cells in the pathogenesis of hepatitis B virus (HBV) infection has not been explored in depth. In the present study, the activation status of B cells from peripheral blood of healthy controls (N = 20) and patients with acute hepatitis B (AHB, N = 15) or chronic hepatitis B (CHB, N = 30) was evaluated by measuring the expression levels of B-cell activation markers CD69 and CD86, using quantitative real-time PCR and flow cytometry. Moreover, the potential mechanism underlying B-cell activation during HBV infection was further investigated by analyzing the expression profile of FCRL1, an intrinsic activation molecule of B cells. An elevation in the levels of B-cell activation markers including CD69 and CD86 was observed in the AHB patients (44.31 ± 9.27, 27.64 ± 9.26%) compared to CHB patients (30.35 ± 11.27, 18.41 ± 6.56%, P < 0.05), which was still higher than healthy controls (12.23 ± 7.84, 8.22 ± 3.43%, P < 0.05). Furthermore, the expression of FCRL1 was found to be similar to B-cell activation markers, which was highest in AHB patients (70.15 ± 17.11%), lowest in healthy donors (36.32 ± 9.98%, P < 0.05) and half-way between these levels in patients with CHB (55.17 ± 12.03%, P < 0.05). The results were positively associated with aberrant B-cell activation. These data suggest that B cells can play a role in HBV infection, and therefore more effort should be devoted to exploring their functions.

The expression profile of Fc receptor-like Y in B lymphocytes with hepatitis B virus induced diseases.

The Fc Receptor-like Y (FcRY) molecule is preferentially expressed by B lymphocytes and has recently been considered as a potential therapeutic target for B cell malignancies. In this study, we investigated the correlation between FcRY expression profile, B lymphocytes population and different HBV infection disease status. The FcRY expression level on B lymphocytes and the number of B lymphocytes population from peripheral blood in 27 healthy controls (HC) and 65 patients with HBV-induced diseases, including chronic hepatitis B (CHB), liver cirrhosis (LC) and hepatocellular carcinoma (HCC), were analyzed using quantitative real-time PCR and flow cytometry. The results showed the level of FcRY expression and frequency of germinal center (GC) B lymphocytes from peripheral blood were significantly correlated with the HBV-related disease status, which was highest in HCC and LC patients, lowest in healthy donors, and in the middle in patients with CHB. Our study indicates that there is a significant correlation between FcRY expression profile, B lymphocytes population and HBV-induced diseases. However, the roles of FcRY and B lymphocytes in HBV-induced diseases are unclear and need further investigation.

Overexpression of Fc receptor-like 1 associated with B-cell activation during hepatitis B virus infection

The role of B cells in the pathogenesis of hepatitis B virus (HBV) infection has not been explored in depth. In the present study, the activation status of B cells from peripheral blood of healthy controls (N = 20) and patients with acute hepatitis B (AHB, N = 15) or chronic hepatitis B (CHB, N = 30) was evaluated by measuring the expression levels of B-cell activation markers CD69 and CD86, using quantitative real-time PCR and flow cytometry. Moreover, the potential mechanism underlying B-cell activation during HBV infection was further investigated by analyzing the expression profile of FCRL1, an intrinsic activation molecule of B cells. An elevation in the levels of B-cell activation markers including CD69 and CD86 was observed in the AHB patients (44.31 ± 9.27, 27.64 ± 9.26%) compared to CHB patients (30.35 ± 11.27, 18.41 ± 6.56%, P < 0.05), which was still higher than healthy controls (12.23 ± 7.84, 8.22 ± 3.43%, P < 0.05). Furthermore, the expression of FCRL1 was found to be similar to B-cell activation markers, which was highest in AHB patients (70.15 ± 17.11%), lowest in healthy donors (36.32 ± 9.98%, P < 0.05) and half-way between these levels in patients with CHB (55.17 ± 12.03%, P < 0.05). The results were positively associated with aberrant B-cell activation. These data suggest that B cells can play a role in HBV infection, and therefore more effort should be devoted to exploring their functions.

[The study on the STAT3 labeled by GFP affecting the migration of BEL-7402 cell line].

Signal transducers and activators of transcription (STATs) are key DNA-binding proteins in JAK/STATs signal pathway. Aberrant expression and activation of STAT3 have been identified in many kinds of tumors. We report here that constitutive activation of STAT3 was present in BEL-7402 cells. We constructed the fusing genes of STAT3 (wild type/mutant) and GFP to study the function of constitutively activated STAT3 in BEL-7402 cells. By measuring the migration of the cells labeled by GFP-STAT3(WT/CYF), we proved that overexpression of STAT3(WT) could augment the migration of BEL-7402 cells, while STAT3(CYF) could decrease the migration.