OBJECTIVETo observe the structural and functional changes in islet beta cells in severely scalded rats, and to explore its relationship with dysfunction of glycometabolism.

METHODSSeventy-two Wistar rats were divided into scald (S) group and sham injury (SI) group according to the random number table, with 36 rats in each group. Rats in group S were inflicted with 50%TBSA full-thickness scald by a 12-s immersion of back and a 6-s immersion of abdomen in 94 °C hot water. Rats in group SI were sham injured through immersion of back and abdomen in 37 °C warm water. At post injury hour (PIH) 6 and on post injury day (PID) 3 and 7, plasma glucose level was measured for intraperitoneal glucose tolerance test (IPGTT) in 12 rats of each group, and the area under the curve (AUC) of plasma glucose level was calculated. After the IPGTT, pancreatic tissue was harvested and subjected to a double immunostaining for insulin and cell nuclei to determine the pancreatic insulin-positive area ratio, and the area and number of beta cells in the islets (referred to as "the three indicators in the islets"). Data were processed with the analysis of repeated measures and factorial designed analysis of variance, and LSD test was applied for paired comparison.

RESULTS(1) At PIH 6 and on PID 3, the overall plasma glucose levels of rats in group S before and after injection of glucose and at each time point were obviously higher than those of rats in group SI (with F values of main effects respectively 79.372 and 32.962, P values all below 0.001; with P values of paired comparison below 0.05 or 0.01). On PID 7, the overall plasma glucose levels in the two groups before and after injection of glucose and at each time point were close (with P values all above 0.05). (2) The overall AUC of plasma glucose levels of rats in group S was higher than that of rats in group SI (main effects: F = 337.87, P < 0.01). Compared with those of rats in group SI [(1019 ± 32), (1003 ± 72) mmol·min·L(-1)], the AUCs of plasma glucose levels of rats in group S were higher at PIH 6 and on PID 3 [(1501 ± 163), (1132 ± 67) mmol·min·L(-1), P values all below 0.001]. The AUCs of plasma glucose levels were close between two groups on PID 7 (P > 0.05). The AUCs of plasma glucose levels on PID 3 and 7 were both lower than that at PIH 6 in rats of group S (with P values all below 0.001). (3) The three indicators in the islets in rats of group S were all lower than those of rats in group SI (with F values of main effects respectively 135.17, 24.75 and 39.35, P values all below 0.01). There were no significant differences in the three indicators in the islets at PIH 6 between two groups (with P values all above 0.05). The three indicators in the islets of rats in group S on PID 3 and 7 [0.47 ± 0.05, 0.51 ± 0.07; (0.032 ± 0.008), (0.037 ± 0.008) mm(2); (303 ± 64), (341 ± 58) cells] were significantly lower than those of rats in group SI [0.63 ± 0.05, 0.64 ± 0.06; (0.043 ± 0.011), (0.044 ± 0.012) mm(2); (398 ± 112), (387 ± 90) cells; P < 0.05 or P < 0.01] and that at PIH 6 within group S (P < 0.05 or P < 0.01).

CONCLUSIONSThe number of beta cells is reduced, and the insulin secretion function of beta cells is decreased in the scalded rats, and they may constitute the cause of dysfunction of glycometabolism, mainly manifested as hyperglycemia.

Animals ; Blood Glucose ; metabolism ; Burns ; metabolism ; Insulin ; metabolism ; Insulin-Secreting Cells ; metabolism ; Male ; Rats ; Rats, Wistar

OBJECTIVETo investigate the expression and procoagulant activity of phosphatidylserine (PS) on the normal peripheral blood cells of adults.

METHODSNormal peripheral blood samples were collected from 10 healthy volunteers (5 ml from each volunteer), platelets, neutrophils, lymphocytes and erythrocytes were isolated. The expression and procoagulant activity of PS on normal blood cells were identified by flow cytometry, inhibition test with lactadherin as PS probe and coagulation anticoagulant, respectively.

RESULTSThere was PS expression on a few normal blood cells (9.1%, 5.4%, 3.9% and 3.2% in platelets, neutrophils, lymphocytes and erythrocytes, respectively). The PS on these normal blood cells in vitro showed significant procoagulant activity. The plasma recalcification time was shortened by 47%, 36.5%, 25% and 12.5% by platelets, neutrophils, lymphocytes and erythrocytes, respectively; the formation of factor Xa (through both intrinsic and extrinsic pathways) and thrombin was also increased by 13% - 26% by platelets, neutrophils, lymphocytes and erythrocytes, respectively.

CONCLUSIONThe PS on normal blood cells in vivo may play a crucial role in the coagulation cascade.

Adult ; Blood Cells ; metabolism ; physiology ; Blood Coagulation Tests ; Female ; Flow Cytometry ; Humans ; Male ; Phosphatidylserines ; metabolism

Biomimetics ; Blood Cells ; metabolism ; CD55 Antigens ; blood ; CD59 Antigens ; blood ; Cell Membrane ; Humans ; Male ; Submarine Medicine

OBJECTIVETo study the effects of experimental varicocele (VC) on the serum testosterone (T) and intratesticular testosterone in adolescent rats.

METHODSA VC rat model was established by partial ligation of the left kidney vein in 20 SD rats, and another 20 were included in a sham operation group as controls. At 4 and 8 weeks, the concentrations of the serum T and intratesticular T were measured by radioimmunoassay (RIA). The testis tissues were homogenized and the extract liquid taken for RIA.

RESULTSCompared with the controls, the level of serum T declined at 4 and 8 weeks in the VC group, but not significantly (P > 0.05), so was that of bilateral intratesticular T at 4 weeks, and with statistical significance at 8 (P < 0.01).

CONCLUSIONWithin 8 weeks, experimental VC could reduce the level of bilateral intratesticular T, but not that of serum T. Varicocele could damage Leydig cells.

Animals ; Leydig Cells ; Male ; Rats ; Rats, Sprague-Dawley ; Testis ; metabolism ; Testosterone ; blood ; metabolism ; Varicocele ; metabolism

Resistin, a newly discovered peptide hormone mainly secreted by adipose tissues, is present at high levels in serum of obese mice and may be a potential link between obesity and insulin resistance in rodents. However, some studies of rat and mouse models have associated insulin resistance and obesity with decreased resistin expression. In humans, no relationship between resistin level and insulin resistance or adiposity was observed. This suggests that additional studies are necessary to determine the specific role of resistin in the regulation of energy metabolism and adipogenesis. In the present study, we investigated the effect of resistin in vivo on glucose and lipid metabolism by over-expressing resistin in mice by intramuscular injection of a recombinant eukaryotic expression vector pcDNA3.1-Retn encoding porcine resistin gene. After injection, serum resistin and serum glucose (GLU) levels were significantly increased in the pcDNA3.1-Retn-treated mice; there was an obvious difference in total cholesterol (TC) level between the experiment and the control groups on Day 30. In pcDNA3.1-Retn-treated mice, both free fatty acid (FFA) and high density lipoprotein (HDL) cholesterol levels were markedly lower than those of control, whereas HDL cholesterol and triglyceride (TG) levels did not differ between the two groups. Furthermore, lipase activity was expressly lower on Day 20. Our data suggest that resistin over-expressed in mice might be responsible for insulin resistance and parameters related to glucose and lipid metabolism were changed accordingly.
Animals ; Blood Glucose ; analysis ; Cholesterol, HDL ; blood ; Cholesterol, LDL ; blood ; Fatty Acids, Nonesterified ; blood ; Glucose ; metabolism ; HeLa Cells ; Humans ; Lipid Metabolism ; Male ; Mice ; Resistin ; blood ; physiology ; Triglycerides ; blood

OBJECTIVETo investigate effects of serum HDL(1) on the formation of foam cells from human peripheral blood monocyte-derived macrophages.

METHODSSectie density polyacrylamide gel electrophoresis (sd-PAGE) was applied for isolation and preparation of HDL(1) simultaneously. Monocytes were isolated from human peripheral blood by Ficoll-Hypaque density gradient centrifugation and plastic adsorptive process. The isolated monocytes were stimulated by phorbol 12-myristate 13-acetate (PMA) at a concentration of 50 nmol/L for 48 h and transferred to macrophages. The monocyte-derived macrophages were then coincubated with 80 mg/L ox-LDL and HDL(1) (0, 0.1, 1.0 and 10.0 mg/L) for 6, 12 and 24 h, respectively. The formation of foam cells was identified by transmission electron microscope (TEM), total cholesterol (TC), free cholesterol (FC) and protein (Pro) in cultured cells were quantitatively analyzed by high performance chromatography (HPLC) and modified lowry protein assay, respectively.

RESULTSHDL(1) isolated from human serum by sd-PAGE could significantly decrease TC/Pro ratio in foam cells in a concentration-dependent (0 mg/L: 36.9 +/- 1.1, 10.0 mg/L: 6.2 +/- 0.4, P < 0.01) and time-dependent (10.0 mg/L HDL(1) 6 h: 16.9 +/- 0.9, 24 h: 6.4 +/- 0.6, P < 0.01) manner.

CONCLUSIONHDL(1) is capable of inhibiting and attenuating the formation of foam cells by decreasing cellular TC, therefore, might play an important role in attenuating atherosclerosis.

Atherosclerosis ; Cells, Cultured ; Cholesterol, LDL ; metabolism ; Foam Cells ; cytology ; metabolism ; Humans ; Lipoproteins, HDL ; blood ; Lipoproteins, LDL ; Monocytes ; cytology ; metabolism

OBJECTIVE: To explore the effect of hypoxia-supported umbilical cord mesenchymal stem cell (UC-MSC) on the expansion of cord blood mononuclear cell （MNC） in vitro. METHODS: The isolated cord blood mononuclear cells were inoculated on the preestablished umbilical cord mesenchymal stem cell layer and cultured under hypoxic conditions (3％ O₂) and the experimental groups were normoxia (MNCs were cultured under normoxic conditions), hypoxia (MNCs were cultured under hypoxic conditions), UC-MSC (MNCs were cultured with UC-MSC under normoxic conditions), and UC-MSC+hypoxia (MNCs were cultured with UC-MSC under hypoxic conditions). To further investigate the combinational effect of 3 factors of SCF+FL+TPO (SFT) on expansion of cord blood MNCs in vitro in hypoxia-supported UC-MSC culture system, the experiments were further divided into group A (MNCs were cultured with UC-MSC and SFT under normoxic conditions), group B (MNCs were cultured with UC-MSC under hypoxic conditions), group C (MNCs were cultured with UC-MSC and SFT under hypoxic conditions). The number of nucleated cells (TNC), CD34⁺ cell, CFU and CD34⁺CXCR4⁺, CD34⁺CD49d⁺, CD34⁺CD62L⁺ cells of each groups were detected at 0, 7, 10 and 14 days, respectively. RESULTS: Compared with group hypoxia and UC-MSC, group UC-MSC+hypoxia effectively promoted the expansion of TNC, CD34⁺ cell and CFU, and upregulated the expression level of adhesion molecule and CxCR4 of the cord blood CD34⁺ cell（P<0.05）. After culturing for 14 days, compared with group A and group B, group C effectively promoted the expansion of cord blood MNC at different time points（P<0.05）, and the effect of group A was better than that of group B at 7 and 10 days（P<0.05）. CONCLUSION Hypoxia-supported UC-MSC efficiently promoted the expansion and expression of adhesion molecule and CXCR4 of cord blood CD34⁺ cell, and the effect of expansion could be enhanced when SFT 3 factors were added.
Humans ; Cells, Cultured ; Fetal Blood ; Cell Proliferation ; Umbilical Cord/metabolism* ; Mesenchymal Stem Cells ; Antigens, CD34/metabolism* ; Hypoxia/metabolism*

AIMThe gene encoding neurotrophic factor was transfected into brain capillary endothelial cells with the aim of delivering the gene product extensively into the brain parenchyma by making use of the secretory function of BCECs.

METHODSPlasmid DNA encoding mouse glial cell-derived neurotrophic factor (mGDNF gene) was constructed and prepared. Then, mGDNF gene was transfected into cultured mouse brain capillary endothelial cells (BCECs) in vitro. The amount of mGDNF protein in the transfected cells and secreted from the transfected cells were determined by ELISA. The polarity of the secretion of mGDNF protein from BCECs was investigated in a bicameral culture system.

RESULTSThe mGDNF protein was detected out not only from the transfected cells but also the cultured media. And mGDNF protein was mainly found in the brain side of the culture compartment.

CONCLUSIONIt has been demonstrated that a secretory protein can be successfully delivered into brain parenchyma by utilizing the secretory pathway of BCECs.

Animals ; Blood-Brain Barrier ; Brain ; cytology ; metabolism ; Cells, Cultured ; Culture Media ; metabolism ; Endothelial Cells ; metabolism ; secretion ; Mice ; Plasmids ; Transfection

The objective of this study was to investigate the expressions of TPO receptor (c-mpl) proteins on CD34 positive bone marrow cells (CD34+ BMCs), platelets and the expression of c-mpl mRNA in bone marrow cells of the patients with polycythemia vera (PV). The expressions of c-mpl proteins on CD34+ bone marrow hematopoietic cells of 13 PV patients and 15 normal controls were assessed by bicolor flow cytometry and the expressions of c-mpl proteins on platelets of 15 PV patients and 15 normal controls were assessed by monocolor flow cytometry, and the expressions of c-mpl mRNA in bone marrow hematopoietic cells (BMHCs) were assessed by RT-PCR. The results showed that no difference was found between the expression of c-mpl proteins on CD34+ BMHCs of PV patients (0.99% +/- 0.14%) and that of normal controls (0.92% +/- 0.12%) (p > 0.05). There was no difference too between the expression of c-mpl protein on platelets in PV patients (20.33% +/- 4.84%) and that in normal controls (23.50% +/- 3.64%) (p > 0.05). No difference between the expression of c-mpl mRNA in BMHCs of PV patients and that in normal controls was seen. In conclusion, the expressions of c-mpl proteins on CD34+ BMHCs, platelets and c-mpl mRNA in BMHCs of PV patients were not obviously abnormal.
Antigens, CD34 ; analysis ; Blood Platelets ; metabolism ; Bone Marrow Cells ; metabolism ; pathology ; Hematopoietic Stem Cells ; metabolism ; pathology ; Humans ; Polycythemia Vera ; genetics ; metabolism ; RNA, Messenger ; metabolism ; Receptors, Thrombopoietin ; metabolism

The study was aimed to explore the influence of co-culture ex vivo of CD34+ cells from two units of cord blood (CB) on the homing-related adherent molecule expression of each other. Mesenchymal stem cells (MSCs) were obtained from human bone marrow. Two units of CB CD34+ cells were co-cultured on 12 Gy gamma-ray irradiated MSC layer. Their adherent molecule expressions were assessed by flow cytometry. The results showed that the purity of the isolated CD34+ cells was (98.25+/-0.93)%. After co-culture on MSC layer for 6 days, the proportion of CD34+ cells of each unit was dropped to (60.4+/-6.32)% and (60.2+/-5.12)% respectively, but there was no significant difference from the control groups. The expressions of CD44, CD62L, CD184 and CD26 on CD34+ cells of each unit remained unaffected. The expression of CD162 was downregulated and CD54 was first increased but then dropped to the level before co-culture. But there was no significant difference between the experimental and control groups. In conclusion, co-culture of CD34+ cells from two units of CB may have no effects on the adherent molecule expressions of each other.
Antigens, CD34 ; metabolism ; Bone Marrow Cells ; cytology ; Cell Adhesion Molecules ; metabolism ; Coculture Techniques ; Fetal Blood ; cytology ; metabolism ; Hematopoietic Stem Cells ; cytology ; metabolism ; Humans ; Mesenchymal Stromal Cells ; cytology