Transport of protein in the form of small peptides(di/tripeptides) across the small intestinal wall is a major route of dietary proteins absorption.The H + coupled dipeptide transporter,PepT1,located in the intestine and the kidney,plays an important role in the absorption of di/tripeptide;in addition,it mediates the intestinal absorption of ? lactam antibiotics,angiotensin converting enzyme inhibitors,and other peptide like drugs.The human intestinal cell line Caco 2 is an in vitro model.The dipeptide transporters normally found in the small intestine are present in Caco 2 cells.Caco 2 cells spontaneously differentiate in culture to polar cells possessing microvilli and enterocytic properties.These cells have been evaluated in detail as a model to study both transcellular and paracellular transport of nutrients and drugs in the gut.

Objective To compare curative effects between posterior approach microendoscopic discectomy (MED) and traditional open discectomyin the treatment of lumbar spinal stenosis (LSS). Methods A total of 70 cases of lumbar spinal stenosis from October 2000 to December 2002 were divided into two groups: the MED Group ( n =30) and the Open Group ( n =40). Curative outcomes were compared between the two groups. Results The rate of excellent or good results was 93.3% in the MED Group (28/30) and 90.0% in the Open Group (36/40), without statistically significant difference ( ? 2 =0.819, P =0.664). The operation time was significantly shorter in the MED Group than in the Open Group ( t =2.295, P =0.025). The intraoperative blood loss was significantly less in the MED Group than in the Open Group ( t =-42.344, P =0.000). The time to normal activities in the MED Group was significantly shorter than that in the Open Group ( t =-30.123, P =0.000). Conclusions Curative effects of MED are identical with those of traditional surgery in the treatment of lumbar spinal stenosis, but shorter operation time, less blood loss and quicker postoperative recovery are achieved in MED.

Vascular endothelial cells (EC) and smooth muscle cells (SMC) are target and effecter cells of inflammation, and they play an important role in inflammatory responses. The abnormal structure and function of EC and SMC play a significant role in microcirculation disturbance in septic shock and multiple organ dysfunction. This review was meant to discuss the changes in structure and function of EC and SMC and their bidirectional regulation. The cellular linkage of EC and SMC is essential for the interactions between them, and it contributes to the course of sepsis. Paracrine and autocrine as produced by EC and SMC constitute a network for mutual adjustment. Replication of the interaction between EC and SMC facilitates the potential to support hemodynamics, tissue perfusion and cellular metabolism, thereby lower the mortality rate of sepsis. However, the detailed and specific mechanisms remain to be disclosed.

Objective To investigate the suppressive effect of carbon monoxide-releasing molecule Ⅱ (CORM-2) on LPS induced platelet α-granule exocytosis in sepsis via soluble N-ethylmaleimide-sensitive factor attached protein receptor/mammalian uncoordinated 18b (SNARE/Munc18b) complex formation.Methods Blood was collected from healthy volunteers' cubital vein, then platelets were isolated by differential centrifugation. Platelets were randomly divided into 5 groups. The control group did not undergo any treatment, the LPS group received 10 mg/L LPS simulation, the CORM-2 group and iCORM-2 group underwent LPS simulation and immediate administration of CORM-2 (10μmol/L and 50μmol/L) or iCORM-2 (50μmol/L), respectively. Samples were incubated in a CO2-incubator at 37 ℃, 95% humidity, and 5% CO2. Platelet α-granule contents were detected by using standard enzyme linked immunosorbent assay (ELISA), including platelet factor 4 (PF4), platelet derived growth factor-BB (PDGF-BB), and matrix metalloproteinase-2 (MMP-2). The expression of P-selectin was detected by flow cytometer. Transmission electron microscope and immunofluorescence microscope was used to assess platelet α-granules distribution. Expressions of Munc18b and SNARE proteins including vesicle-associated membrane protein-8 (VAMP-8), synaptosomal-associated protein-23 (SNAP-23) and syntaxin-11 (STX-11) were detected by Western Bolt. The SNARE/Munc18b complex formation was detected by immunoprecipitation.Results Compared with the control group, levels of PF4, PDGF-BB, MMP-2 and P-selectinin LPS-induced platelets were found to markedly elevated, while CORM-2 (10μmol/L and 50μmol/L) could decrease platelet α-granule contents exocytosis: [PF4 (μg/L): 7.69±0.58, 6.03±0.71 vs. 10.13±0.82; PDGF-BB (μg/L): 112.71±1.79, 102.91±5.86 vs. 128.78±1.39; MMP-2 (ng/L): 32.94±2.73, 27.58±3.36 vs. 53.26±1.21; P-selectin: (17.14±0.57)%, (15.35±0.68)% vs. (23.78±0.62)%; allP < 0.01]. Transmission electron microscope and immunofluorescence microscope showed that the extent of platelet α-granules assembled to platelet plasma membrane was significantly decreased following CORM-2 treatment. Compared with the control group, the expressions of Munc18b and SNARE proteins and SNARE/Munc18b complex formation in LPS-stimulated platelets were significantly increased, while CORM-2 (10μmol/L and 50μmol/L) inhibited these elevations (Munc18b/GAPDH: 0.80±0.08, 0.69±0.01 vs. 0.99±0.09; VAMP-8/GAPDH: 0.72±0.09, 0.50±0.12 vs. 1.18±0.14; SNAP-23/GAPDH: 1.18±0.22, 0.63±0.10 vs. 1.90±0.08; STX-11/GAPDH: 0.76±0.02, 0.57±0.08 vs. 1.16±0.23; VAMP-8/ Munc18b: 0.65±0.09, 0.53±0.07 vs. 1.21±0.20; SNAP-23/Munc18b: 0.85±0.07, 0.55±0.09 vs. 1.26±0.08; STX-11/ Munc18b: 0.78±0.05, 0.61±0.10 vs. 1.39±0.16; allP < 0.01). Above all, the data showed a dose dependent change.Conclusion We could suggest that CORM-2 suppressed α-granule exocytosis in LPS-stimulated platelets and the potential mechanisms might involve SNARE/Munc18b complex formation.

Objectives: To determine the regulation effects of recombinant human growth hormone(rhGH) on dipeptide transport(PepT1) in normal and severe scalded rats. Methods: Male Sprague Dawley rats inflicted by 30% total body surface area ( TBSA) Ⅲ degree scalding were employed as the model.The rhGH was used in this study with the dose of 2 U/(kg?d). An everted sleeve of intestine was incubated in Kreb’s solution with radioactive dipeptide ( 3 H Glycylsarcosine, 3 H Gly Sar, 10 ?Ci / ml) at 37℃ for 15 min to measure the effects of uptake and transport of PepT1 of small intestinal epithelial cells in normal and severe scalded rats. Results: The transport of dipeptide in normal rats with injection of rhGH was not significantly increased compared with controls ( P =0.192 6) while the uptake was significantly increased compared with controls ( P = 0.025 3 ). The transport and uptake of PepT1 in scalded rats with injection of rhGH were significantly increased compared with controls( P = 0.008 2 and 0.039 1). Conclusions: The effects of uptake and transport of dipeptide transporters in small intestinal epithelial cells with severe injury were markedly upregulated by rhGH.

Objective To investigate the inhibitory effect of kukoamine B (KB) on lung inflammatory responses in mice with sepsis and its possible molecular mechanism.Methods Twenty-eight male mice were randomly divided into control group (n=8),lipopolysaccharide (LPS) group (n=10),and LPS + KB group (n=10).Sepsis model was reproduced by intra-peritoneal injection of 20 mg/kg LPS,while equivalent normal saline was given in control group,and 20 μg/kg KB was injected through caudal vein 4 hours after LPS challenge in LPS + KB group.After 8 hours of LPS challenge,the concentration of LPS in plasma and the activity of myeloperoxidase (MPO) in the lung tissue were determined.The contents of tumor necrosis factor-α (TNF-α) and interleukin-lβ (IL-1β) in plasma,alveolar lavage fluid and lung tissue homogenates were assessed by enzyme linked immunosorbent assay (ELISA).The activation of nuclear factor-κB (NF-κB) and the expression of inducible nitric oxide synthase (iNOS) in lung tissue were determined by Western Blot.The pathological changes in lung tissues were observed with hematoxylin-eosin (HE) staining.The expression of intercellular adhesion molecule-1 (ICAM-1) in lung tissue was determined by immunohistochemistry.Results Compared with control group,the concentration of LPS in plasma (kEU/L:1 155.650 ± 147.149 vs.31.390 ± 18.859),MPO activity (U/g:1.177 ±0.093 vs.0.775 ±0.166),NF-κB activity (gray value:1.557 ±0.105 vs.0.824 ±0.032) and the expression of iNOS (gray value:0.650 ±0.129 vs.0.392 ±0.097) were significantly increased in LPS group (all P＜0.05).After KB intervention,the concentration of LPS (624.461 ± 149.012),MPO activity (0.919 ±0.023),NF-κB activity (1.127 ±0.074) and the expression ofiNOS (0.425 ± 0.066) were significantly lowered (all P＜0.05).Compared with control group,the contents of TNF-α (ng/L:47.325 ± 13.864 vs.6.534 ± 0.544,13.382 ± 2.231 vs.3.748 ± 0.692,31.127 ± 7.399 vs.14.948 ± 4.673) and IL-1β (ng/L:74.329 ± 11.890 vs.29.921 ± 6.487,9.422 ± 2.674 vs.1.105 ± 0.364,528.509 ± 32.073 vs.109.945 ± 13.561) in plasma,alveolar lavage fluid and lung tissue homogenates were obviously enhanced in LPS group (all P＜0.05).With KB intervention,the contents of TNF-α (20.331 ± 7.789,7.145 ± 1.202,15.966 ± 2.946) and IL-1β (57.707 ±8.098,2.212 ± 0.878,426.154 ± 11.270) were markedly reduced (plasma TNF-α:F=16.052,P=0.002; IL-1β:F=20.649,P=0.000; lung tissue homogenates TNF-α:F=31.134,P=0.001; IL-1β:F=22.792,P=0.002;alveolar lavage fluid TNF-α:F=10.013,P=0.009; IL-1β:F=319.857,P=0.000).In addition,leukocyte infiltration to the lung tissue was attenuated,and the expression of ICAM-1 was reduced by KB in histological examination.Conclusion KB,as a neutralizer of LPS,can inhibit the release of inflammatory mediators,reduce the pulmonary inflammatory response and protect the function of lung in septic mice.

Objective To determine the inhibitory effect and mechanism of exogenous carbon monoxide against excessive neutrophil infiltration in liver and lung tissues during sepsis.Methods Thirty-two mice were subjected to sham operation (sham group),cecal ligation and perforation (CLP) group,CLP with 8 mg/kg of exogenous carbon monoxide releasing molecule Ⅱ (CORM-2) (CORM-2 group),and CLP with 8 mg/kg of inactive variants of CORM-2 (iCORM-2) (iCORM-2 group) according to the random number table,with 8 mice per group.Liver and lung tissues were collected at 24 hours after surgery to examine the pathologic changes,myeloperoxidase (MPO) activity and malonaldehyde (MDA) content.Another 60 mice were enrolled into the same 4 groups with 15 mice per group and were tested for 72-hour survival rate.Bone marrow neutrophils were isolated and divided into normal control group,1 μg/ml lipopolysaccharide (LPS) group,1 μg/ml LPS plus 10 μmol/L CORM-2 group (low dose group),1 μg/ml LPS plus 50 μmol/L CORM-2 group (high dose group),1 μg/ml LPS plus 50 μmol/L iCORM-2 group (iCORM-2 group).Under the agarose chemotaxis,qPCR and immunofluorescence detection of formyl peptide receptor 1 (FPR1) were performed.Results CLP group presented enhanced activity of MPO [liver:(9.1 ± 1.1) U/g,lung:(16.3 ± 2.8) U/g],increased MDA content [liver:(76.5 ±11.3) nmol/mg,lung:(32.4 ± 10.3) nmol/mg] and 72-hour survival rate of 20％ as compared with the sham group (all P ＜ 0.05).CORM-2 group showed inhibited activity of MPO [liver:(5.2 ± 0.8) U/g,lung:(7.5 ± 2.4) U/g],increased MDA content [liver:(46.7 ± 6.1) nmol/mg,lung:(23.8 ±7.3) nmol/mg] and 72-hour survival rate of 67％ as compared with the sham group (all P ＜ 0.05).LPS enhanced neutrophil migration (61.3 ± 7.1) (P ＜ 0.05) and expression of FPR1 which was enriched in the membrane.Meanwhile,neutrophil migration was significantly inhibited in a dose-dependent of CORM-2 (low dose group:43.3 ±6.1,high-dose group:23.3 ±5.9) (P＜0.05).Conclusions Exogenous carbon monoxide is effective to inhibit the excessive neutrophil infiltration,attenuate oxidative stress or pathological injury,and improve the survival from sepsis.The mechanism is associated with the down-regulation of FPR1,inhibition of FPR1 enrichment in the membrane,and decreased neutrophil migration.

ObjectiveTo study the role of Kukoamine B (KB) in inhibiting the inflammatory response of small intestine in septic mice and its molecular mechanisms.Methods Twenty-four male ICR mice were randomly divided into control group, model group, and KB intervention group (each,n= 8). Sepsis model was reproduced by intra-peritoneal injection of 20 mg/kg lipopolysaccharide (LPS), while equivalent normal saline was given in control group, and 20μg/kg KB was injected through caudal vein 4 hours after LPS challenge in KB intervention group. The blood/tissue samples (jejunum and ileum) were harvested 8 hours after LPS injection. The levels of plasma LPS, tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were measured. The pathological changes in small intestine tissues were observed under light microscope, while the levels of inflammatory cytokines TNF-α and IL-1β in the tissue homogenates (jejunum and ileum) were assessed by enzyme linked immunosorbent assay (ELISA). The activity of myeloperoxidase (MPO) was measured by colorimetry. The expression of intercellular adhesion molecule-1 (ICAM-1) was determined by immunohistochemistry. The expressions of inducible nitric oxide synthase (iNOS) mRNA was assayed by reverse transcription-polymerase chain reaction (RT-PCR). The activation of nuclear factor-κΒ (NF-κΒ) was determined by Western Blot.Results The mice in model group were found to have an increase in microvascular permeability, interstitial edema, and infiltration of white blood cells, and the levels of LPS, TNF-α and IL-1β in their plasma, with an increase in concentrations of TNF-α and IL-1β, activity of MPO, positive expression of ICAM-1, expression of iNOS mRNA and NF-κB protein in small intestine (jejunum and ileum). Compared with model group, in mice with KB intervention, microvascular permeability, interstitial edema, and infiltration of white blood cells were reduced significantly, while the levels of LPS, TNF-α and IL-1β in plasma, the concentration of TNF-α and IL-1β, the activity of MPO, the positive expression of ICAM-1, the expression of iNOS mRNA and NF-κB protein in small intestine (jejunum and ileum) were significantly decreased [plasma LPS (kEU/L): 654.09±28.13 vs. 1 155.65±47.15, TNF-α (ng/L): 12.75±0.47 vs. 30.61±0.71, IL-1β (ng/L): 53.06±5.32 vs. 64.47±2.61; jejunum TNF-α(ng/L): 43.27±1.20 vs. 64.82±2.09, IL-1β (ng/L): 326.38±14.47 vs. 535.22±13.48, MPO (U/g): 0.14±0.01 vs. 0.32±0.02, iNOS mRNA (2-ΔΔCt): 2.39±0.13 vs. 10.80±0.22, NF-κB protein (gray value): 0.687±0.062 vs. 1.404±0.046; ileum TNF-α (ng/L): 62.75±3.92 vs. 104.24±2.82, IL-1β(ng/L): 408.06±1.70 vs. 521.97±1.16, MPO (U/g): 0.36±0.08 vs. 0.66±0.05, iNOS mRNA (2-ΔΔCt): 1.65±0.11 vs. 3.59±0.29, NF-κB protein (gray value):0.830±0.114 vs. 1.609±0.051, allP< 0.05].Conclusion KB can combine with LPS and inhibit LPS/Toll-like receptor 4 (TLR4) signaling pathway, thereby significantly inhibit the inflammatory response and protect the function of the small intestine in LPS-induced septic mice.

Objective:To investigate the application valve of bFGF to improve the viability of subdermal vascular network flap.Methods:Four white healthy pigs were used,each pig had 6 SVNF on back,16cm?4cm,totally 24 flaps were divided randomly into 2 groups:The bFGF groups and the control groups.On postoperative day 6,we observed the appearance of the flaps.The survival area of each flap was measured and the flap was harvested for histological analysis and the density of angiogenesis was also examined.Results:On postoperative day 6,the survival rates of the bFGF group and the control group were (81.2?1.7)% and (66.2?1.8)% respectively,the angiogenesis density of the middle and the distal segment in the bFGF group was (16.7?6.0)/mm2,(29.7?5.5)/mm2,(14.9?6.0)/mm2 respectively,while (16.6?4.0)/mm2,(21.4?5.2)/mm2,(3.5?5.1)/mm2 respectively in the control group.The bFGF group was superior to the control group in the appearance and histological analysis of the flaps.Conclusion:The results suggest that the injection of bFGF locally can promote the survival rate by accelerating the blood circulation of the SVNF’ bottom and edge,shorten the division time of SVNF and broaden the ratio of length and width.

Objective To investigate the suppressive effect of exogenous carbon monoxide (CO) on abnormal platelet exocytosis and its possible molecular mechanism. Methods Venous blood was collected from healthy volunteers. Platelet-rich plasma (PRP) was isolated from the blood by differential centrifugation. The PRP was randomly divided into five groups by random number table, namely normal control group, lipopolysaccharide (LPS) group (challenged with 10 mg/L LPS), inactively exogenous carbon monoxide releasing molecule 2 (iCORM-2) group (given 10 mg/L LPS + 50 μmol/L iCORM-2 for intervention), exogenous carbon monoxide releasing molecule 2 (CORM-2) 10 μmol/L and 50 μmol/L groups (given 10 mg/L LPS + CORM-2 10 μmol/L or 50 μmol/L for intervention). After 30 minutes, enzyme linked immunosorbent assay (ELISA) was used to determine the platelet-derived growth factor BB (PDGF-BB) and matrix metalloproteinase 2 (MMP-2). Chemical fluorescein method was used to determine the platelet adenosine triphosphate (ATP). Flow cytometer was used to determine the expression of P-selectin. The expressions of Toll-like receptor 4 (TLR4), phosphorylation of protein kinase Cθ (PKCθ) and syntaxin binding protein 1 (STXBP-1) were determined by Western Bolt. The soluble N-ethylmaleimide-sensitive factor-attachment protein receptors (SNAREs) complex formation [syntaxin 2-synaptosomal-associated protein 23-vesicle associated membrane protein 8 (STX2-SNAP23-VAMP8)] mediated by STXBP-1 was determined by immunoprecipitation. Results ① Compared with normal control group, the platelet release of PDGF-BB, MMP-2 and ATP was significantly increased after LPS challenge, and the P-selectin expression of platelet was also obviously up-regulated [PDGF-BB (μg/L): 127.53±1.78 vs. 94.35±5.84, MMP-2 (ng/L): 51.87±9.20 vs. 35.83±3.17, ATP (μmol/L): 1.288±0.056 vs. 0.975±0.010, P-selectin: (3.93±0.19)% vs. (0.44±0.10)%, all P < 0.05]. The increases in platelet release of PDGF-BB, MMP-2 and ATP were suppressed by 10 μmol/L or 50 μmol/L CORM-2 administration, as well as high-expression of P-selectin in a dose-dependent manner [PDGF-BB (μg/L): 114.68±1.35, 97.08±6.14 vs. 127.53±1.78, MMP-2 (ng/L): 32.67±8.00, 24.63±1.63 vs. 51.87±9.20, ATP (μmol/L): 0.999±0.015, 0.965±0.008 vs. 1.288±0.056, P-selectin: (1.95±0.27)%, (0.94±0.11)% vs. (3.93±0.19)%, all P < 0.05]. ② Compared with normal control group, LPS challenge resulted in a significant increase in the expression of TLR4 and the phosphorylation of PKCθ and STXBP-1 [TLR4 (gray value): 1.21±0.38 vs. 0.67±0.06, p-PKCθ (gray value): 1.36±0.20 vs. 0.44±0.03, p-STXBP-1 (gray value): 1.13±0.06 vs. 0.59±0.04, all P < 0.05]. The increases in above parameters were suppressed by 10 μmol/L or 50 μmol/L CORM-2 administration in a dose-dependent manner [TLR4 (gray value): 0.76±0.05, 0.65±0.04 vs. 1.21±0.38; p-PKCθ (gray value): 0.71±0.07, 0.47±0.10 vs. 1.36±0.20; p-STXBP-1 (gray value): 0.56±0.02, 0.48±0.01 vs. 1.13±0.06, all P < 0.05]. ③ Compared with normal control group, the SNAREs proteins in platelet that combined with STXBP-1, including STX2, SNAP23 and VAMP8, were obviously increased after LPS challenge [STX2 (gray value): 1.35±0.06 vs. 0.57±0.04, SNAP23 (gray value): 0.97±0.04 vs. 0.30±0.12, VAMP8 (gray value): 1.37±0.12 vs. 0.77±0.10, all P < 0.05]. The increases in SNAREs complex formation were suppressed by 10 μmol/L or 50 μmol/L CORM-2 administration in a dose-dependent manner [STX2 (gray value): 0.77±0.02, 0.39±0.03 vs. 1.35±0.06, SNAP23 (gray value): 0.41±0.03, 0.22±0.08 vs. 0.97±0.04, VAMP8 (gray value): 0.85±0.07, 0.66±0.07 vs. 1.37±0.12, all P < 0.05]. There was no significant difference in the above mentioned parameters between iCORM-2 group and LPS group. Conclusions LPS-induced abnormal secretion of platelet was suppressed by CORM-2 administration. The mechanism may involve the TLR4/PKCθ/STXBP-1 signaling pathway activation and the SNAREs complex formation.