To study the location and expression characteristics of epidermal stem cells in normal skin and scar epidermis of children, and to explore the relationship between the differences of these two epidermal stem cells and wound healing after burn. ?1 integrin and keratin 19 (K19) were used as the biochemical markers to identify stem cells and transit amplifying cell, keratin 14 (K14) and keratin 10 (K10) were used as the markers for post-mitotic cells and terminally-differentiated cells, respectively. Normal skin and scar tissue were obtained from children of 4 to 12 years of age. Elivision two-step immunohistochemistry was used. The results showed that in the immunostained tissue sections, the positive ?1 integrin and K19 expression cells were observed in 2～3 layers above the basal layer, whereas K10 expression cells were observed in all epidermal cells except basal cell layer in the scar tissue. Observations revealed that the number of stem cells and transit amplifying cells were less in the scar tissue than that in the normal skin, the differentiation process of scar epidermal stem cells was different from that of normal skin, and the proportion between post-mitotic cells and terminally-differentiated cells was abnormal. The results indicated that the self-renewal ability of the scar epidermis was lowered, and the differentiation process of it was deranged, and this might be considered to be a reason of abnormality of structure and function of the epidermis of scar tissue, and its poorer ability in wound healing.

To gain insight into the mechanisms of an age related difference in ability of wound healing, the characteristics of stem cell differentiation in skins from fetus, child and adult were investiga ted. Integrin ? 1 and keratin 19 (K19) were used as the biochemical markers for stem cells and transit amplifying cells. Biopsies were taken from fetus (22～24week gestational age), children (4～12year) and adults (35～53year). Immunohistochemistry was used. As for the immunostainings of fetal tissue sections, integrin ? 1 and K19 expressions were observed in all epidermal basal cells. In children skin, the ratio of integrin ? 1 and K19 positive cells in the epidermal basal layer was 60%～80%. In adults, the ratio in the epidermal layer decreased. These results indicate that fetal skin epidermis contains a large number of stem cells and transit amplifying cells, and the proportion of stem cells and transit amplifying cells decreases with age after birth, which maybe a reason of the age associated difference in ability of wound healing.

Epstein-Barr virus (EBV)infection is highly prevalent in general population,serum EBV antibody can be detected in about 90% of the adults.Forty years of researches have demonstrated that EBV infection is closely related to a variety of hematological diseases,such as infectious mononucleosis, EBV-related lymphoproliferative disorders,lymphoma and hemophagocytic syndrome.This paper reviews EBV-associated hematological diseases and its pathogenic mechanism.

BACKGROUND: Previous studies have proved platelet-rich fibrin (PRF) with osteoinduction ability, and the centrifugal speed and time to prepare rabbit advanced PRF (A-PRF) with the most similar structure to that of human PRF have been determined.OBJECTIVE: To observe the histological changes during A-PRF-induced osteogenesis.METHODS: Thirty Japanese white rabbits were randomly divided into A-PRF and blank control groups (n=15 per group).The full-thickness defect models were established on the rabbit parietal bone, followed by implanted with A-PRF or nothing, respectively. The model rabbits were killed immediately, at 2, 4, 8 and 12 weeks after modeling, to grossly observe the bone formation, and the histological changes in the defect region were observed through hematoxylin-eosin staining, Masson staining and immunohistochemistry.RESULTS AND CONCLUSION: Unhealed defects were observed in the blank control group. Gross and histological observations showed that the speed, amount and maturity of bone formation in the A-PRF group were significantly better than those in the blank control group immediately, 4, 8 and 12 weeks after modeling (P < 0.05). Our findings suggest that the rabbit skull bone defect is successfully established. A-PRF can induce osteogenesis, and more mature newly born bones appear with time. Additionally, osteoclasts can act with osteoblasts synergically under the A-PRF induction to promote the bone formation.

This study was aimed to identify Bletilla Striata (Thunb.) Reichb.f.and Bletilla Formosana (Hayata) Schltr.by ITS2 sequence.The leaves of 38 samples of Bletilla striata and Bletillaformosana from Yunnan,Hubei,Guizhou,Hunan and Sichuan province were used as experiment materials.The total DNA was extracted.Internal transcribed spacer 2 (ITS2) sequences were obtained by PCR.All of the ITS2 sequences were checked.The 8 ITS2 sequences from two species were downloaded from GenBank.The intraspecific and interspecific Kimura-2-parameter (K2P) distances of Bletilla striata and Bletilla formosana were calculated by MEGAS.0.And neighbor-joining (NJ) tree was constructed.The results showed that the full-length sequences of ITS2 from Bletilla striata and Bletillaformosana were 259 bp,with a total of 14 variable sites.The maximum intraspecific K2P distance of Bletilla striata and Bletillaformosana was 0.008,while the minimum interspecific K2P distance was 0.040.The ITS2 secondary structure showed that different origins of Bletilla striata were gathered together and could be distinguished obviously from Bletilla formosana by NJ tree.It was concluded that ITS2 sequence was able to identify Bletilla striata and Bletillaformosana quickly and accurately.

Objective To establish HPLC fingerprint of Radix Gentianae Crassicaulis.Methods The fingerprints were obtained on an Ultimate XB-C18 column(250 mm?4.6 mm,5 ?m)with the gradient elution solvent system composed of acetonitrile and 0.05% phosphoric acid.The flow rate was 1.0 mL/min,the column temperature was maintained at 25 ℃,and the detection wavelength was set at 240 nm.Results Ten common peaks were selected as the fingerprint peaks and the fingerprints also were evaluated by the Similarity Evaluation System for Chromatographic Fingerprint with the correlation coefficient of 0.98—1.0.Conclusion This method with good precision and reproducibility is reliable for the quality control of Radix Gentianae Crassicaulis.

Objective To explore the effects of different approaches of stem cell therapy in patients with leukemia on haptoglobin(Hp).Methods The trial includes four patients treated by mesenchymal stem cell(MSC)with hematopoietic stem cell cotransplantation(HSCT)and two patients treated by hematopoietic stem cell transplantation(HSCT).Haptoglobin in the plasma,collected from different therapeutic stages,of six patients was separated by two-dimensional gel electrophoresis(2-DE),and then followed by the identification with MALDI-TOF/TOF mass spectrometry.Results The abundance of haptoglobin alpha and beta chains with different modifications decreased along with an extending therapeutic time window.This tendency was more significant in HSCT group.Conclusion The haptoglobin may be a potential biomarker for the prognosis in patients with leukemia treated by stem cell transplantation.

The purpose of the present work is to observe whether Tau protein Ser202/Thr205 is hyperphosphorylated in braintissues of diabetic mice and to study the effect of App17 peptide. Mouse diabetic model was produced with streptozotocin, andApp1 7 peptide as a treatment was injected subcutaneously into diabetic mice. Four weeks later, fixative was injected intravascu-larly into the mice, the brain was removed and crystat sections prepared. Immunohistochemical staining was done with AT-8. Inthe brains of diabetic mice positive AT-8 reacting neurons were numerous, darkly stained, and widely distributed in retrosplenialgranular cortex, hippocampus, thalamus et al. , while in normal mice and App17 peptide-treated diabetic mice positive cells werescarce and poorly stained. Tau protein is hyperphosphorylated at Scr202/Thr205 site and widely distributed in the brains of dia-betic mice, while App17 peptide can normalize the expression of AT-8 positive cells.