Prompt peripheral nerve regeneration induced by a hierarchically aligned fibrin nanofiber hydrogel.

Fibrin plays a crucial role in peripheral nerve regeneration, which could occur spontaneously in the format of longitudinally oriented fibrin cables during the initial stage of nerve regeneration. This fibrin cable can direct migration and proliferation of Schwann cells and axonal regrowth, which is very important to nerve regeneration. In the present study, we prepared a three-dimensional hierarchically aligned fibrin nanofiber hydrogel (AFG) through electrospinning and molecular self-assembly to resemble the architecture and biological function of the native fibrin cable. The AFG displayed a hierarchically aligned topography as well as low elasticity (∼1.5kPa) that were similar to nerve extracellular matrix (ECM) and the native fibrin cable. Rapid, directional cell adhesion and migration of Schwann cells (SCs) and dorsal root ganglions were observed in vitro. The AFG was then used as a potential intraluminal substrate in a bioengineered chitosan tube to bridge a 10-mm-long sciatic nerve gap in rats. We found that the AFG served as a beneficial microenvironment to support SCs cable formation and axonal regrowth within 2weeks. Further histological and morphological analyses as well as electrophysiological and functional examinations were performed after AFG implantation for up to 12weeks. The results from morphological analysis and electrophysiological examination indicated that regenerative outcomes achieved by our developed graft were close to those by an autologous nerve graft, but superior to those by hollow chitosan tubes (hCST) and random fibrin nanofiber hydrogel (RFG). Our results demonstrate that the AFG creates an instructive microenvironment by mimicking the native fibrin cable as well as the oriented and soft features of nerve ECM to accelerate axonal regrowth, thus showing great promising potential for applications in neural regeneration. STATEMENT OF SIGNIFICANCE: In peripheral nervous system defect repair, a wide variety of strategies have been proposed for preparing functionalized nerve guidance conduits (NGC) with more complex configurations to obtain optimal repair effects. Longitudinally oriented fibrin cables were reported to form spontaneously during the initial stages of peripheral nerve regeneration in an empty NGC, which can direct the migration and proliferation of Schwann cells and promote axonal regrowth. Therefore, based on the biomimetic idea, we prepared a three-dimensional hierarchically aligned fibrin nanofiber hydrogel (AFG) through electrospinning and molecular self-assembly, resembling the architecture and biological function of the native fibrin cable and serving as an intraluminal filling to accelerate axon regeneration. We found that the AFG was a beneficial microenvironment to support SCs cable formation and accelerate axonal regrowth with improved motor functional recovery.

[Clinicopathologic study of 128 cases of T-lymphoblastic lymphoma/leukemia].

OBJECTIVE: To clarify clinical and morphological features and immunophenotype of T lymphoblastic lymphoma/leukaemia (T-LBL/ALL) and to further improve the knowledge and diagnostic accuracy for T-ALL/LBL. METHODS: 128 cases of T-LBL/ALL were analyzed for the clinical features, morphology, immunophenotype and TCR gene rearrangement using routine eosin and haematoxylin stain, immunohistochemistry and polymerase chain reaction combining with the clinical findings. RESULTS: In 128 cases of T-LBL/ALL, there were 94 male and 34 female. The ratio of male/female was 2.8:1. The age of patients ranged from 4 to 88 years, with an average of 27 years and a median of 22 years. Lymph nodes and extranodal areas were involved in 58/128 and 27/128 cases of T-LBL/ALL, respectively. The other 43 cases had involvement of both nodal and extranodal areas. Cervical node and mediastinum were involved in 74 cases and 43 cases, respectively. Diffuse growth pattern of tumor cells was predominant. Nodular growth pattern was seen only in a few cases. Most cases composed of small to medium-sized lymphoblasts, and other 7 cases showed a composition of large lymphoblasts. Tumor cells expressed TdT in 121/128 (94.5%) cases, CD34 in 48/98 (49.0%) cases, CD3 in 78/108 (72.2%) cases, CD7 in 104/108 (96.3%) cases, CD43 in 56/63 (88.9%) cases, CD79a in 5/70 (7.1%) cases, CD10 in 25/76 (32.9%) cases, CD99 in 58/60 (96.7%) cases and Pax-5 in 4/91(4.4%) cases. All of the cases were negative for MPO. A follow up data, ranging from 1 to 53 months, was obtained in 51/128 (39.8%) patients. The over all survival rate was 68.6% and the median survival time was 12 months. Under a similar condition of carrying a positive staining result on CD3 in tumor cells, there was a statistically significant difference between patients in the group of over 30 of age and that with the age ranging from 11 to 30. Patients associating with a CD10 positive staining of tumor cells showed also a shorter survival period. In addition, there were 4 out of 5 cases showing the presence of TCR gene rearrangement. CONCLUSIONS: T-LBL/ALL are aggressive in behavior, associating mainly with enlarged cervical lymph nodes and masses in the mediastinum, occurring predominantly in children and young adults. Although small to medium-sized tumor cells with diffuse pattern were found in most cases, however, large-sized tumor cells and nodular pattern could also be obtained in a few cases. Immunohistochemistry staining particularly adoption of CD7, Pax-5, TdT, CD34 and Ki-67 stainings in combination are helpful of making a diagnosis for T-LBL/ALL. Analysis of TCR gene rearrangement will be helpful for the diagnosis of a few difficult cases.

Reduced expression and novel splice variants of ING4 in human gastric adenocarcinoma.

ING4, a new member of the ING (inhibitor of growth) family of tumour suppressor genes, has been found to be deleted or down-regulated in gliomas, breast tumours, and head and neck squamous cell carcinomas. The goal of the present study was to investigate whether the expression and alternative splicing of ING4 transcripts are involved in the initiation and progression of stomach adenocarcinoma. ING4 mRNA and protein expression was examined in gastric adenocarcinoma tissues and human gastric adenocarcinoma cell lines by RT-PCR, real-time RT-PCR, tissue microarray immunohistochemistry, and western blot analysis. Alterations in ING4 transcripts were determined through sequence analysis of ING4 cDNA. Our data showed that ING4 mRNA and protein were dramatically reduced in stomach adenocarcinoma cell lines and tissues, and significantly less in female than in male patients. We also found that reduced ING4 mRNA expression correlated with the stage of the tumour. Interestingly, by sequence analysis, we discovered five novel aberrantly spliced variant forms of ING4_v1 and ING4_v2. These variants cause a codon frame-shift and, eventually, deletion of the NLS or PHD domain contributing to the mislocalization of p53 and/or HAT/HDAC complexes and, subsequently, altered gene expression in gastric adenocarcinoma. These results suggest that attenuated and aberrant ING4 expression may be involved in the initiation and progression of stomach adenocarcinoma.

Role of soluble ceruloplasmin in iron uptake by midbrain and hippocampus neurons.

Ceruloplasmin (CP) is essential for brain iron homeostasis. However, its precise function in brain iron transport has not been definitely determined. In this study, we investigated the effects of soluble CP on iron influx and efflux in primary neuronal culture from the midbrain (the substantia nigra and striatum) and the hippocampus. Our data showed that low concentrations of CP (2, 4, 8 microg/ml) can promote iron influx into iron-deficient neurons, but not the neurons with normal iron status. The same concentrations of CP had no effect on iron efflux from iron-sufficient and normal-iron neurons. Contrary to our expectation, we did not find any regional difference in the effects of CP on iron influx as well as efflux in neurons. The changes in quenching (iron influx) and also dequenching (iron efflux) of intracellular fluorescence, induced by the addition of CP with iron, in the midbrain neurons were no different from those in the hippocampus neurons. The data showed that soluble CP has a role in iron uptake by iron-deficient brain neurons under our experimental conditions. The physiological significance of the results forms the focus for future work.

Vascular endothelial growth factor and microvascular density in esophageal and gastric carcinomas.

AIM: To observe the relationship between the expression of vascular endothelial growth factor (VEGF), microvascular density (MVD) and the pathological characteristics of esophageal and gastric carcinomas. METHODS: S-P immunohistochemical staining was used to investigate the expression of VEGF in all the specimens. The antibody against factor VIII-related antigen was used to display vascular endothelial cells, and MVD was examined by counting the factor VIII-positive vascular endothelial cells. RESULTS: The positive rates of VEGF expression in esophageal carcinoma and gastric carcinoma were 81.36 % and 67.5 % respectively, and the MVD averaged 41.81+/-8.44 and 34.36+/-9.67 respectively, which were higher than those in benign diseases. The expression of VEGF and MVD were closely correlated with the degree of differentiation, lymphatic metastasis, but not related to depth of cancer invasion. In early stage gastric carcinoma, the rate of expression of VEGF and MVD was lower than that in progressive gastric carcinomas. CONCLUSION: The expression of VEGF is correlated with tumor angiogenesis, and VEGF plays an important role in new blood vessels formation, the expression of VEGF and MVD play an important role in tumor growth and metastasis. MVD and the expression of VEGF may be two important indexes for patients' prognosis.