Animals ; Diaphragm ; physiopathology ; Electrophysiological Phenomena ; physiology ; Hypoxia ; physiopathology ; Male ; Rats ; Rats, Wistar ; Sleep Apnea Syndromes ; physiopathology

OBJECTIVE:In recent years, chitosan has been widely used as tissue engineering scaffolds. In this paper we reviewed the research progress in chitosan biocompatibility and gave a hypothesison possible mechanism of interactions between cells and chitosan. A model system to test this hypothesis was also discussed. DATA SOURCES: Literatures about chitosan biocompatibility were retrieved with computer in Medline, Pubmed and Elsevier from January 1998 to December 2006 with the key words of."chitosan, biocompatibility, surface charge, cell adhesion" in English.STUDY SELECTION: Literatures about chitosan biocompatibility and interactions between chitosan and cells, especially the influence of chitosan charges on cell attachment, were included, whereas repeated experiments were excluded.DATA EXTRACTION: Totally 374 literatures were collected. Among which, 30 were admitted and reviewed.DATA SYNTHESIS: Many mammalian cells can adhere, spread and proliferate on chitosan materials. It is widely accepted that the biocompatibility of chitosan is due to the electrostatic attractive force between positively charged amino groups on chitosan chains and negatively charged cell membranes. However, the pKa value of chitosan amino groups is 6.2-6.8 and the positive charge of chitosan chains is largely decreased under physiological condition as a result of amino groups unprotonation. Thus whether the chitosan's biocompatibility is due to its positive charge remains doubtful and needs further study.CONCLUSION: Based on prior studies, we hypothesize that the positive charge of amino groups on chitosan chains might not be the major factor in biocompatibility of chitosan material. Agarose/chitosan blending hydrogels is supposed to be an appropriate model system to test this hypothesis.

Adenocarcinoma, Bronchiolo-Alveolar ; metabolism ; pathology ; Antigens, CD34 ; metabolism ; Diagnosis, Differential ; Female ; Hemangioendothelioma, Epithelioid ; metabolism ; pathology ; surgery ; Hemangioma ; metabolism ; pathology ; Hemangiosarcoma ; metabolism ; pathology ; Humans ; Lung Neoplasms ; metabolism ; pathology ; surgery ; Middle Aged ; Vimentin ; metabolism

Nerve growth factor is one of the most important factors playing an important role in regulating the growth, development and survival of the neuron. The purified NGF from human placenta has been reported, the tissue from which can be isolated the NGF is very limited. It is important for basic research and clinic application to expression hNGF by genetic engineering. By polymerase chain reaction,gene fragment encoding the mature part of ?-NGF was amplified using the DNA of human placenta as template. The fragment was sequenced and inserted into expression vector pET-15b, and the recombinant expression vector pET15b-NGF was transformed into E.coli BL21(DE3)pLysS. After inducing with IPTG the NGF was higher expressed up to 25% of the total cell proteins. The expression product was purified with metal chelate affinity chromatography on Ni-IDA agarose under denaturing condition. The purity of rNGF was higher than 90% and yield of rNGF was 4.56mg/L expressing bacteria. SDS-PAGE revealed the NGF expression product had a Mr 16kDa. Western-blot displayed the recombinant product had strong immunological activity with rabbit anti-human ?-NGF polyclonic antibodies. The expression products were dealed with solubilizing inclusion bodies and refolding protein. The test of nerve fiber growth of chicken embryo DRG neurons displayed rNGF had biological activity.

Self-cloning is a favorable technique in modification of industrial microorganisms especially food microorganisms because of its bio-safety. A survey and outlook of research in breeding of self-cloning industrial brewing yeast were introduced in this study.

To study the biological characteristics and mutations of influenza A(H1N1)pdm09 virus isolated from one case of pneumonia of unknown etiology (PUE),which would provide references for clinical treatment and disease control,the throat swab specimen from the PUE case was isolated in the Madin-Darby Canine Kidney (MDCK) cells,and then the antigenicity,pathogenicity and drug resistance of influenza A (H1N1) pdm09 virus were analyzed after sequencing.As a result,one influenza virus strain was isolated from the specimen and named as A/FujianGulou/SWL64/2016(H1N1).The similarities of nucleotide sequences and amino acids sequences compared with the vaccine strain A/California/07/2009 (H1N1) were 96.9％-98.9％ and 96.7％-99.5％,respectively.Eighteen amino acids had mutated in the HA and 4 mutations,K163Q,S185T,S203T and D222N,were involved in 3 different epitopes,which indicated that the antigenic drift had occurred in the influenza virus.The D222N mutation associated with receptor binding site made the virus infect lower respiratory tract more easily.The virus was still amantadine-resistance and oseltamivir-sensitive.In conclusion,the influenza A (H1N1) pdm09 virus in this study have occurred antigenic drift and has the molecular characterization of causing severe pneumonia,so further surveillance should be performed to prevent and control the influenza epidemic.

Aged ; Female ; Hodgkin Disease ; diagnosis ; pathology ; Humans ; Reed-Sternberg Cells ; pathology

Tumors of synchronous benign and malignant in unilateral salivary glands have rarely been reported. A case of 21-year-old girl who was diagnosed as synchronously adenoid cystic carcinoma of the left parotid and pleomorphic adenoma of the left submandibular gland. The classification, clinic pathology, diagnosis, possible mechanism were discussed based on similar literatures.
Adenoma, Pleomorphic ; Carcinoma, Adenoid Cystic ; Female ; Humans ; Salivary Glands ; Young Adult

Adult ; Antigens, Neoplasm ; analysis ; Diagnosis, Differential ; Female ; Humans ; Immunohistochemistry ; Magnetic Resonance Imaging ; Melanoma ; cerebrospinal fluid ; metabolism ; pathology ; Melanoma-Specific Antigens ; Melanosis ; cerebrospinal fluid ; metabolism ; pathology ; Meningeal Neoplasms ; cerebrospinal fluid ; metabolism ; pathology ; Meninges ; chemistry ; pathology ; Neoplasm Proteins ; analysis ; S100 Proteins ; analysis

Objective To investigate clinical symptoms,pathophysiology and brain imaging features of Chinese familial cerebral cavernous angiomas.Methods Head MRI examination,clinical and pathophysiological examination were performed in a Chinese family with one proband of cerebral cavernous malformation.The disease atlas of the family was drawn.The patients indicative of a surgery underwent resection of hemangioma whose pathophysiology and microstructure were observed.Results Nine familial cerebral cavernous angiomas patients were found to have multiple intracranial lesion in the 18 family members,the penetrance being 50%,conforming to the feature of autosomal incomplete dominance inheritance.Four patients with skin cavernous hemangioma had familial cerebral cavernous angiomas.MRI was the most sensitive modality for the diagnosis of cavernous angioma.With T_2-Weighted sequences,the lesion was typically characterized by an area of mixed signal intensity,with a central reticulated core and a peripheral rim of decreased signal intensity related to deposition of hemosiderin.Gradient-echo(GRE)MRI could find microcavernous hemangiomas that would not be found in other sequences.Cavernous angiomas were typically discrete multilobulated berrylike lesions that contained hemorrhage in various stages of evolution.Histological homogeneity and overlap with other vascular malformations such as capillary telangictasia was common.Cavernous angiomas were composed of endothelial-linked sinusoidal spaces not separated by significant amounts of neural tissue.Hemorrhagic residua were common.Clots at different stages of evolution within the lesion were seen.The basic membranes of sinus became thick and soft.Parts of it were layered.Conclusions Familial cerebral cavernous angiomas is an autosomal incomplete dominance inheritance disease.Cavernous angiomas are composed of endothelial-linked sinusoidal spaces not separated by significant amounts of neural tissue.There are more than one focus in every patients and the skin cavernous angiomas is the foundation of diagnosing familial cerebral cavernous angiomas.Gradient-echo imagine sequence MRI(3.0 T)could be the"golden standard".