Stromal cell derived factor (SDF), expressing on bone marrow stromal cells is a CXC-type chemokine, which specifically chemoattracts hematopoietic stem cells (HSCs) expressing CXCR4. SDF plays important roles in homing and mobilizing of HSCs. In this paper the regulatory mechanism of SDF/CXCR4 in the HSC migration process is mainly reviewed.
Chemokine CXCL12 ; Chemokines, CXC ; physiology ; Hematopoietic Stem Cell Mobilization ; Humans ; Receptors, CXCR4 ; physiology ; Signal Transduction

Background Since the measurement method establishment of serum ferritin abroad in early period of theseventies, the iron deficiency had been divided into two types: the non-anemia and anemia types. In orderto go step further studies, we must ertablish the bemoglobin targets of the two types. Methods One hurdred and fifty-two children in experimontal group, from 6 to 7 years old, and allcome from Qinghai province. There are 29 children in Xining city, 24 in Guide, 26 in Gongbe, 40 in Gui-nan and 33 in Maduo countics. There are 36 health children aged from 6 to 7 years old in the controlgroup, and all comes from Beijing. The Hb, RBC, HCT, HCTW and FEP wcre determined. Results The three targets correlating with Hb (Hb, MCH and MCHC); correlating with RBC (RBC,HCT and MCV); the two targets correlating with RBC_weight (HCTW and CMCW) and correlating withFEP of RBC(FEP and MCEP) have very significant difference between experimental group and control group. Conclusion The determination values of the 10 targets are not same in children in different districts,and the values of all the target: are increased on different degree along with the increase in altitude of ele-vation. There is very important significance on the studies of iron deficiency and altitude hypoxia to establish the normal values of the 10 targets.

Objective To evaluate the chemopreventive effects of boswellic acid and curcumin on 7,12-dimethyl benzanthracene (DMBA)-induced oral carcinogenesis in the hamster cheek pouch model.Methods Male Syrian golden hamsters(6-8 weeks old,80-130 g in weight) were randomly divided into seven groups,with group A serving as the untreated negative control.The left cheek pouch of the remaining hamsters was topically treated with 0.5％ DMBA in mineral oil three times a week for 6 weeks.They were then randomized to six groups with group B serving as a positive control and receiving no further treatment.Groups C-G were treated topically with 5,10 mg/L boswellic acid,5,10 μ moL/L curcumin,or the combination of 5 mg/L boswellic acid and 5 μmnol/L curcumin three times per week for 18 weeks.The animals were injected with bromodeoxyuridine intraperitoneally at 50 mg/kg 2 h prior to killing.At the 25 th week all the hamsters were sacrificed and cheek pouch tissue was harvested.One half of the tissue was snap frozen in liquid nitrogen for analysis of arachidonic acid metabolites,and the other half was fixed in 10％ phosphate-buffered saline(PBS)-buffered formalin for histopathological examination.Results Six-weeks of DMBA followed by 18-weeks of topical application of boswellic acid and curcumin,both boswellic acid (5,10 mg/L) and curcumin (5,10 μmol/L) significantly inhibited the incidence from 93.8％ to 73.9％ (P＞0.05),numbers from 2.19 ± 0.98 to 1.13 ± 0.81 (P ＜ 0.01) and size of visible tumors.Microscopically the incidence of squamous cell carcinoma and BrdU index were also significantly suppressed by boswellic acid and curcumin.Conclusions Both boswellic acid and curcumin were effective in preventing oral carcinogenesis in DMBA-induced hamster cheek pouch model.

Objective Make use of image dentate nucleus and the veins around it on susceptibility weighted images (SWI), explore the correlation between the location of hilum of dentate nucleus and the venous variation of dentate nucleus. Methods Selecting 51 healthy adults (24 men, 27 women) at the age between 18 and 30 years old to get the original images on 3. 0T MR. Process the original images by minimum intensity projections (mIP) observed and analyzed the morphology of dentate nucleus and veins around it on original and processed images. Results The length of dentate nucleus was (16. 64±0. 20)mm, and the width was (8. 36±0. 14)mm. There was no significant difference between bilateral dentate nucleus. The median angle of the long axis of the dentate nucleus was 26. 80° (interquartile distance was 34. 58°). The venous network of dentate nucleus was formed in 2 groups of veins: the lateral group, drained by the vein of the horizontal fissure and nuclear vein; the medial group, drained by vermian vein and central vein of dentate nucleus. These two groups had been further typing as follows: the lateral anterior group drained by the nuclear vein, finally opening to superior petrosal sinus; the lateral median group had plenty of small veins of lateral dentate nucleus converge into the vein of the horizontal fissure; the lateral posterior group drained by a lot of very small veins converging to vermian veins or medullary veins; the medial anterior group that the central vein of dentate nucleus and the paravermian vein were jointed at hilum of dentate nucleus, opening into straight sinus; the medial posterior group usually converged into tributaries of vermian vein, or converged with paravermian vein into tributaries of vermian vein. Totally 75. 49% of hilums of dentate nucleus were located at upper inner quadrant, the other 24. 51% of them were located at lower inner quadrant. Conclusion Dentate nucleus and its veins are clearly visible on the susceptibility weighted images, and the location of the hilum of dentate nucleus may be related to the abouchement of paravermian vein.

Objective: To analyze the prevalence and the risk factors of fungal sepsis in 25 neonatal intensive care units (NICU) among preterm infants in China, and to provide a basis for preventive strategies of fungal sepsis. Methods: This was a second-analysis of the data from the "reduction of infection in neonatal intensive care units using the evidence-based practice for improving quality" study. The current status of fungal sepsis of the 24 731 preterm infants with the gestational age of <34⁺⁰ weeks, who were admitted to 25 participating NICU within 7 days of birth between May 2015 and April 2018 were retrospectively analyzed. These preterm infants were divided into the fungal sepsis group and the without fungal sepsis group according to whether they developed fungal sepsis to analyze the incidences and the microbiology of fungal sepsis. Chi-square test was used to compare the incidences of fungal sepsis in preterm infants with different gestational ages and birth weights and in different NICU. Multivariate Logistic regression analysis was used to study the outcomes of preterm infants with fungal sepsis, which were further compared with those of preterm infants without fungal sepsis. The 144 preterm infants in the fungal sepsis group were matched with 288 preterm infants in the non-fungal sepsis group by propensity score-matched method. Univariate and multivariate Logistic regression analysis were used to analyze the risk factors of fungal sepsis. Results: In all, 166 (0.7%) of the 24 731 preterm infants developed fungal sepsis, with the gestational age of (29.7±2.0) weeks and the birth weight of (1 300±293) g. The incidence of fungal sepsis increased with decreasing gestational age and birth weight (both P<0.001). The preterm infants with gestational age of <32 weeks accounted for 87.3% (145/166). The incidence of fungal sepsis was 1.0% (117/11 438) in very preterm infants and 2.0% (28/1 401) in extremely preterm infants, and was 1.3% (103/8 060) in very low birth weight infants and 1.7% (21/1 211) in extremely low birth weight infants, respectively. There was no fungal sepsis in 3 NICU, and the incidences in the other 22 NICU ranged from 0.7% (10/1 397) to 2.9% (21/724), with significant statistical difference (P<0.001). The pathogens were mainly Candida (150/166, 90.4%), including 59 cases of Candida albicans and 91 cases of non-Candida albicans, of which Candida parapsilosis was the most common (41 cases). Fungal sepsis was independently associated with increased risk of moderate to severe bronchopulmonary dysplasia (BPD) (adjusted OR 1.52, 95%CI 1.04-2.22, P=0.030) and severe retinopathy of prematurity (ROP) (adjusted OR 2.55, 95%CI 1.12-5.80, P=0.025). Previous broad spectrum antibiotics exposure (adjusted OR=2.50, 95%CI 1.50-4.17, P<0.001), prolonged use of central line (adjusted OR=1.05, 95%CI 1.03-1.08, P<0.001) and previous total parenteral nutrition (TPN) duration (adjusted OR=1.04, 95%CI 1.02-1.06, P<0.001) were all independently associated with increasing risk of fungal sepsis. Conclusions: Candida albicans and Candida parapsilosis are the main pathogens of fungal sepsis among preterm infants in Chinese NICU. Preterm infants with fungal sepsis are at increased risk of moderate to severe BPD and severe ROP. Previous broad spectrum antibiotics exposure, prolonged use of central line and prolonged duration of TPN will increase the risk of fungal sepsis. Ongoing initiatives are needed to reduce fungal sepsis based on these risk factors.
Infant ; Infant, Newborn ; Humans ; Birth Weight ; Intensive Care Units, Neonatal ; Retrospective Studies ; Tertiary Care Centers ; Infant, Extremely Low Birth Weight ; Gestational Age ; Infant, Extremely Premature ; Sepsis/epidemiology* ; Retinopathy of Prematurity/epidemiology* ; Bronchopulmonary Dysplasia/epidemiology*