[Effects of glucagon on plasma ghrelin level in type 2 diabetes mellitus].

OBJECTIVE: To investigate the effect of glucagon on ghrelin secretion in type 2 diabetes mellitus (T2DM) patients. METHODS: Circulating ghrelin and C-peptide were measured during glucagon stimulation test in 38 cases with T2DM and 30 cases in normal controls (NC) at the 1st Affiliated Hospital of Shantou University from May 2006 to December 2007. RESULTS: (1) There was no significant difference in the fasting C-peptide and fasting ghrelin levels of the NC group were (1.3 +/- 0.6) microg/L and (3.0 +/- 1.0) ng/ml respectively, both not significantly different from those of the T2DM group [(1.2 +/- 0.4) microg/L and (2.7 +/- 0.8) microg/L respectively, P > 0.05 and P > 0.05]; six minutes after the injection of glucagon, the C-peptide level of the T2DM group increased to (2.0 +/- 0.8) microg/L (P < 0.01), and that of the NC group increased to (3.0 +/- 0.8) microg/L (P < 0.01), and the C-peptide level 6 min after of the T2DM group was significantly lower than that of the NC group (P < 0.01). The ghrelin level 6 min after the injection of glucagon of the NC group was (2.3 +/- 0.7) microg/L, significantly lower than that before the injection (P < 0.01). But the ghrelin level 6 min after the injection of glucagon of the T2DM group was (2.9 +/- 0.9) microg/L, NOT significantly different from that before the injection (P > 0.05). (2) Fasting ghrelin level was significantly negatively correlated with the waist circumference (r = -0.343, P < 0.05). CONCLUSION: In healthy subjects exogenous glucagon decreases the ghrelin level. Ghrelin may be associated with the beta-cell hypofunction and first-phase insulin secretion defects in T2DM. Insulin, glucagon, and ghrelin secreted influence each other to regulate glucose homeostasis.

[A series of observation on the expression of TGF-beta1 in the lung of nitrofen-induced congenital diaphragmatic hernia rat model].

OBJECTIVE: To access the expression of transforming growth factor beta1 (TGF-beta1) in the lung of Nitrofen-induced congenital diaphragmatic hernia rat model. METHODS: Twelve timed-pregnant Sprague-Dawley rats were randomly divided into two groups, namely control group and CDH group on day 9.5 of gestation. Each rat in the CDH group was given 125 mg of Nitrofen (dissolved in seed fat) by gavage. Each rat in the control group was given the same dose of single oil. On day 16 of gestation, the two groups mentioned above were divided into three subgroups, and fetuses were delivered by cesarean section respectively on day 16, 18 and 21 of gestation. After the fetuses were checked for diaphragmatic hernia, lung tissue weight (LW) and body weight (BW) of each fetus on gestational day 21 were recorded. Lung histologic evaluations were made with microscope and TGF-beta1 immunohistochemistry staining were performed with image analyzing. RESULTS: At day 16 of gestation, no visible diaphragm closure was observed in all fetuses. Diaphragmatic hernia was observed in 32 of the 44 rat fetuses of the CDH groups on day 18 and day 21 of gestation (72.7%). Lw/Bw of the 21d subgroups of CDH group were lower than those of corresponding control group (P < 0.01). Observed under the microscope, the lungs of fetuses in CDH groups showed marked hypoplasia. The expression of TGF-beta1 was detected in cytoplasmic, without definite expression in nuclear. It was significantly stronger that the expression of TGF-beta1 was in the lungs of the CDH group than that of the control group (P < 0.01). CONCLUSIONS: Nitrofen interferes with lung development in early stage of the fetal before the diaphragm developed. TGF-beta1 would be one of the important factors which lead to pulmonary hypoplasia.

Interferonalpha enhances etoposide-induced apoptosis in human osteosarcoma U2OS cells by a p53-dependent pathway.

Interferonalpha (IFNalpha) induces cell cycle arrest and triggers apoptosis and chemosensitivity. But the mechanism of IFNalpha in regulating chemosensitivity has not been fully understood. To study whether IFNalpha affected chemosensitivity of osteosarcoma cells, we treated p53-wild U2OS cells and p53-mutant MG63 cells with IFNalpha and etoposide, alone or in combination, and then examined growth inhibition, cell cycle arrest and apoptosis. IFNalpha enhanced etoposide-induced growth inhibition and apoptosis in p53-wild U2OS cells but not p53-mutant MG63 cells in a dose- and time-dependent manner. Etoposide-induced G2/M phase arrest was also enhanced by IFNalpha. The enhanced apoptosis was associated with the accumulation of transcriptionally active p53 accompanied with increased Bax and Mdm2, as well as decreased Bcl-2. IFNalpha also activated caspases-3, -8 and -9 protein kinases and PARP cleavage in response to etoposide in U2OS cells. Moreover, the combination-induced cytotoxicity and PARP cleavage were significantly reduced by caspase pan inhibitor and p53 siRNA. Thus we conclude that IFNalpha enhances etoposide-induced apoptosis in human osteosarcoma U2OS cells by a p53-dependent and caspase-activation pathway. The proper combination of IFNalpha and conventional chemotherapeutic agents may be a rational strategy for the treatment of human osteosarcoma with functional p53.

[A morphological study with serial histological slices on the normal and abnormal gubernacula in newborn male mice].

OBJECTIVE: To explore the feasibility of serial slices microscopic histological investigation for the elaborate evaluation of reproductive system malformations. METHODS: Newborn male mice prenatally exposed to different doses of subcutaneously given diethylstilbestrol (DES) from gestational day 9 to 17 were treated by fixing parts of the abdomen in situ and setting them to transected serial slices. All the slices were stained, studied under the microscope and serially recorded by software. The gubernaculum was morphologically analyzed and its location and size were measured. RESULTS: Morphologically, the gubernaculum could be identified clearly, its structure inhomogeneous from proximal to distal and dissymmetric from right to left. The environmental estrogen produced different effects on the morphology of the gubernaculum in different parts and most obviously affected its length. CONCLUSION: Prenatal exposure to environmental estrogen has evident and general effects on the gubernacular development of newborn male mice. The morphological study with serial histological slices gives a precise and systematic evaluation of genital malformations.

[Effect of tetrandrine on endothelin expression in the lungs and clinical significance thereof: experiment with rat models with nitrofen-induced congenital diaphragmatic hernia].

OBJECTIVE: To investigate the effects of tetrandrine on endothelin expression in the lungs and its clinical significance. METHODS: 25 pregnant female SD rats were randomly divided into 5 equal groups: Groups A to D were fed with nitrofen to cause congenital diaphragmatic hernia (CDH) in the fetuses. Group A was injected with normal saline, Group B with dexamethasone (DXM), Group C with tetrandrine, and Group D with DXM + tetrandrine. Group E was control Group. On day 21.5 of pregnancy the fetuses were delivered by cesarean section and killed. Microscopy was used to observe the CDH formation, and the relative wall thickness (RWA) and relative wall area (RWA) of pulmonary arterioles. The lung/body weight ratio, and relative integrated optical density (IOD) of pulmonary arteriole and bronchiole were observed. The expression of endothelin in the lung tissues was detected by immunohistochemistry. RESULTS: 9 rats of Group A-D produced 57 fetuses with CDH with a CDH arte of 45.2%. The lung/body weight ratios, and RWA values of Group A-D were all significantly lower than that of Group E (all P < 0.05). The RWT of pulmonary arteriole was significantly lower in Groups B and C compared with Group E (both P < 0.05). The RWT and RWA of Group A were significantly lower than those of Group B-D (all P < 0.05). The values of relative IOD of pulmonary tissues and of pulmonary arteriole of Group A-D were all significantly lower than those of Group E (all P < 0.05). A positive correlation existed between the relative IOD of endothelin in pulmonary arteriole and in bronchiole (P < 0.01), and among the RWT and RWA of pulmonary arteriole, and relative IOD (all P < 0.01). CONCLUSION: Tetrandrine improves the pulmonary hypoplasia and degrades the pulmonary hypertension.

[Low cement distribution index is a risk factor for refracture of the adjacent segments after percutaneous vertebroplasty].

OBJECTIVE: To investigate the impact of cement distribution index on the occurrence of refracture in the adjacent segments after percutaneous vertebroplasty. METHODS: This retrospective analysis was conducted among 143 patients who received percutaneous vertebroplasty for osteoporotic vertebral compression fracture between April, 2011 and April, 2014. Of the 134 patients with complete follow-up data, 18 had adjacent segment fracture within 1 year following the surgeries (re-fracture group), and 116 patients without new fracture served as the control group. All the patients underwent X-ray examinations after the surgery and according to the position and shape, the cement in the vertebrae were classified into 5 types (I to V), and the volume-cubage index was computed based on the cement volume and vertebral cubage. Age, gender, bone mineral density (BMD), cement distribution index, volume-cubage index, and cement leakage were evaluated in the 2 groups, and the variables with significant differences between the 2 groups were analyzed in Logistic regression analysis. RESULTS: BMD was significantly lower and the rate of cement leakage was significantly higher in the re-fracture group than in the control group (P<0.05). Significant difference was found in cement distribution index between the 2 groups (P<0.05) but not in age, gender, cement volume or volume-cubage index (P>0.05). Logistic regression analysis indicated that BMD, cement leakage and cement distribution index all significantly affected the occurrence of adjacent vertebral fractures following percutaneous vertebroplasty. CONCLUSION: A low BMD, cement leakage and a low cement distribution index are all risks factor of adjacent vertebral fracture after percutaneous vertebroplasty.

Expression of glucocorticoid receptor isoforms in cutaneous hemangiomas and vascular malformations.

BACKGROUND: Hemangiomas are the most common tumors in children. Some hemangiomas may require intervention because of their location, size, behavior, or potential for important complications. Pharmacological therapy with glucocorticoids is the mainstay treatment, but there is no consensus on therapeutic regimens or candidate selection, therapeutic efficacy varies, and the mechanism mediating the beneficial effects of glucocorticoids remains unclear. This study was performed to investigate the expression patterns of the glucocorticoid receptor (GR) and its alpha isoform (GRalpha) in cutaneous hemangiomas and vascular malformations. METHODS: SP immunohistochemical technique was used to examine the expression of GR(e-20) (GR) and GR(p-20) (GRalpha) on vascular endothelial cells in 80 specimens that included 33 proliferating hemangiomas, 32 involuting hemangiomas, 7 vascular malformations as well as 8 normal skin tissues, all obtained from infants and children. GR and GRalpha expression in prepared tissue slides were examined using automated computer-assisted microscopic analysis. Mean gray scale values were compared among the various tumor types. RESULTS: The mean gray scale values of GR were 127.0 +/- 6.4 and 121.4 +/- 6.6 in hemangiomas and vascular malformations respectively, but this difference was not statistically significant (P = 0.104). However, these values were all markedly higher than that of normal skin, which was only 108.6 +/- 6.8 (P = 0.001 and P = 0.000 for comparison with hemangiomas and vascular malformations respectively). The gray scale of GR in proliferation and involuting hemangiomas were 127.9 +/- 4.8 and 126.0 +/- 5.8 respectively, but this difference was not significant (P = 0.146). However, GRalpha expression in hemangiomas, vascular malformations and normal skin declined gradually in stepwise fashion (127.3 +/- 5.4, 120.4 +/- 6.1 and 109.9 +/- 5.3 respectively; P < 0.001). GRalpha expression was higher in proliferating hemangiomas than in involuting hemangiomas (127.2 +/- 6.3 and 122.5 +/- 6.3; P = 0.004). CONCLUSIONS: GR and GRalpha are strongly expressed in hemangiomas and vascular malformations. The expression of GRalpha is closely related to the phase of the hemangioma. Determination of GR and GRalpha may be a positive significance to understand the information of hemangiomas and vascular malformations and may further help determining proper strategies of steroid therapy for hemangiomas and vascular malformations.

Biomechanical assessment of unilateral pedicle screws plus contralateral transfacetopedicular screws after transforaminal lumbar interbody fusion with two cages.

OBJECTIVE: To assess the biomechanical stability of unilateral pedicle screws (UPS) plus contralateral transfacetopedicular screws (TFPS) after transforaminal lumbar interbody fusion (TLIF) with two cages. METHODS: Range of motion (ROM) testing was performed in 28 fresh-frozen human cadaveric lumbar spine motion segments. The sequential test configurations included supplemental constructs after TLIF such as UPS, UPS plus contralateral TFPS and bilateral pedicle screws (BPS). All test specimens were fixated in the normal lordotic lignment, then mounted in a three-dimensional (3-D) motion testing machine and fixed to the load frame of a six degrees of freedom spine simulator. Each of the test constructs were subjected to three load-unload cycles in each of the physiologic planes generating flexion-extension, right-left lateral bending and right-left axial rotation load-displacement curves. Statistical analysis was performed on the ROM data. Comparison of data was performed by repeated-measures analysis of variance for independent samples followed by Bonferroni analysis for multiple comparison procedures. RESULTS: The ROMs for UPS, BPS and UPS plus TFPS fixation after TLIF were significantly smaller than those of the intact spine in all modes. The ROM for UPS plus TFPS fixation was between the largest for UPS and the smallest for BPS. The differences between ROMs of UPS and UPS plus TFPS were significant for both lateral bending and rotation. There were no significant differences between BPS and UPS plus TFPS in any mode. CONCLUSION: Because the UPS construct provides the least stability, especially during lateral bending and rotation, it should be used prudently. After TLIF with two cages, UPS plus TFPS provides stability comparable to that of TLIF with BPS. It is thus an acceptable option in minimally invasive surgery.