Journal of Nanjing Medical University最新文献

Objective

To investigate the effect of activation of angiotensin II (AngII) type 1 (AT1) receptors in the median preoptic nucleus (MnPO) of rats on renal sodium excretion.

Methods

After anesthesia, the rats were injected into the MnPO via an implanted cannula. Urine samples were collected via a bladder cannula, and the urine sodium concentration was assayed with flame spectrophotometry. The serum level of endogenous digitalis-like factor (EDLF) and Na⁺, K⁺-ATPase activity in the renal cortex tissue were assayed respectively with a radioimmunoassay and with an ammonium molybdophosphate-based kit.

Results

Both the urinary volume and the sodium excretion peaked 60 min after AngII was administered into the MnPO. The responses were accompanied by an increase in serum EDLF and a decrease in Na⁺, K⁺-ATPase activity in the renal cortex. The responses of diuresis and natriuresis, as well as an increase in serum EDLF and a decrease in Na⁺, K⁺-ATPase activity in the renal cortex induced by MnPO adminstration with AngII were inhibited by pior treatment with the AngII receptor blocking agent losartan into the MnPO.

Conclusion

These results suggest that activation of AT1 receptors in the MnPO of rat induces diuretic and natriuretic responses. The responses are associated with an increase release of EDLF and with the inhibition of Na⁺,K⁺-ATPase activity in renal cortex tissue.

Hepatic venous stenosis may be a cause of graft failure in living donor liver transplantation (LDLT). Balloon dilation and metallic frame approaches have been used successfully to treat hepatic venous stenosis. Here, we report the effect of transfemoral venous balloon dilation for treating a child with hepatic venous stenosis after LDLT.

Objective

To study the effect of interferon-alpha IFN-α in the serum of SLE patients on the differentiation and maturation of dendritic cells (DCs) derived from CD34⁺ hematopoietic precursor cells (HPCs).

Methods

Serum samples from SLE patients and normal controls were collected and the concentration of IFN-α detected by ELISA. CD34⁺HPCs were purified from cord blood by a magnetic cell sorting system (MACS), and cultured to differentiate to DCs. Normal serum, normal serum with exogenous IFN-α, SLE serum with raised levels of IFN-α, or SLE serum with anti-IFN-α neutralizing antibody was added to the culture medium. The phenotype of DCs was analyzed by flow cytometry (FCM) and the capacity of DCs to stimulate allogenic T lymphocyte proliferation was evaluated in a mixed lymphocyte reaction by the Cell Counting Kit-8. Cytokine production was assessed by ELISA.

Results

Serum levels of IFN-α were significantly higher in SLE patients than in normal controls and this correlated positively with disease activity. Cultured in SLE serum with raised levels of IFN-α, CD34⁺ HPCs could differentiate into DCs that expressed higher levels of HLA-DR, CD80 and CD86, and showed an enhanced allogenic T-cell stimulatory capacity, while producing lower levels of IL-12 and higher amounts of IL-10 compared with those DCs cultured in normal serum.

Conclusion

Increased levels of IFN-α in SLE serum promotes the differentiation and maturation of DCs derived from CD34⁺ HPCs and could contribute to the pathogenesis of SLE.

Objective

To investigate the antiproliferative and apoptogenic activities of polysaccharides extracted from Dioscorea bulbifera L (DBP) and Chinese Angelica (CAP) and a 3:2 mixture of these compounds (DCCP) on two esophageal carcinoma cell lines, EC9706 and Eca109.

Methods

A MTT assay was used to detect the effects of DBP (10 μg/ml and 100 μg/ml), DCCP(17 μg/ml and 170 μg/ml) and CAP (10 μg/ml and 100 μg/ml) on the proliferation of EC9706 and Eca109 cells. DNA content analysis by flow cytometry was used to determine the cell cycle distribution, and Annexin V-FITC/PI stained fluorescence-activated cell sorter (FACS) was used to detect the apotosis rate of treated cells. Western blots were used to examine protein levels.

Results

DBP and DCCP strongly inhibited the proliferation and viability of both the EC9706 and Eca109 cells. CAP enhanced the effects of DBP. DCCP primarily arrested the EC9706 and Eca109 cells at the G1 phase of the cell cycle. DCCP induced apoptosis in both esophageal carcinoma cell lines, and reduced the expression of pIκBα and Bcl-2 proteins.

Conclusion

DCCP triggered apoptosis in esophageal carcinoma cells by inhibiting the NF-κB signaling pathway.

Objective

To explore the in vitro effects of curcumin on the proliferation and apoptosis of the human renal cell carcinoma cell line ACHN, and to investigate its mechanisms of action.

Methods

The human renal cell carcinoma cell line ACHN was treated with different concentrations of curcumin for 24 h. The MTT assay was used to evaluate the cytotoxic effects of curcumin and flow cytometry was utilized to observe and detect the apoptosis of ACHN cells induced by curcumin. The expression levels of Bcl-2, Bax and NF-κBP65 mRNA were evaluated by Reverse Transcription-Polymerase Chain Reaction (RT-PCR), while the expression of Bcl-2, Bax, NF-κBP65 and IκB proteins was evaluated by Western blot.

Results

The concentrations of curcumin used significantly inhibited the proliferation of ACHN human renal cell carcinoma cells in vitro in a dose and time-dependent manner (F_time = 5.55, P < 0.05; F_dose=110.05, P < 0.05). Obvious apoptosis of cells treated with different concentrations of curcumin could be observed by FCM. Compared with the control group, the apoptosis rates of curcumin-treated cells were markedly increased (F=96.35, P < 0.05). Lower dose of curcumin significantly induced the apoptosis of ACHN cells. With intervention of different concentrations of curcumin (0, 10, 20 and 40 μmol/L) for 24 h, the expression levels of Bcl-2 and NF-κBP65 mRNA in ACHN cells were decreased while the expression level of Bax mRNA was increased (P < 0.05), and Bcl-2, and NF-κBP65 protein decreased, while Bax and IκB protein increased compared with those in the untreated group.

Conclusion

Curcumin inhibited proliferation and increased apoptosis of the human renal cell carcinoma cell line ACHN. These curcumin effects appear to involve up-regulating IκB, down-regulating NF-κB, and regulating the expression of the apoptosis genes Bcl-2/Bax.

A case is described of multi-recurrent cervical chordoma in a man over a 5 year period. The clinical features were of progressive spinal cord compression. The authors report a chordoma at C4 that recurred 3 times in five years. The patient underwent four operations and suffered distant metastases. This case confirms that thorough resection of the tumor during the first surgery and post-operative adjuvant treatment are the best assurance of a good prognosis with a chordoma. Multiple surgeries can stimulate biological activity of a chordoma and make its recurrence and distant metastases much more likely. The authors discuss the diagnosis, surgical treatment and the relationship between the histopathological changes and malignancy of a spinal chordoma after four operations. To our knowledge, this represents the first report of a 4th surgery for cervical chordoma.

Objective

To investigate the effects of Panax notoginseng saponins (PNS) on hydrogen peroxide (H₂O₂)-induced apoptosis in cultured rabbit bone marrow stromal cells (BMSCs).

Methods

The effects of different concentrations of PNS on proliferation and early osteoblast differentiation of BMSCs were determined by the MTT assay and an alkaline phosphatase (ALP) assay. An optimal effective concentration of PNS was determined and used in subsequent experiments. The cultured BMSCs were divided into three groups: untreated control, H₂O₂ treated, and PNS pretreatment of H₂O₂ treated. The oxidative stress level was assessed by superoxide dismutase (SOD) and malondialdehyde (MDA) assays. Flow cytometry was used to determine BMSC apoptosis by staining with annexinV-FITC/propidium iodide (PI). The activity of caspase-3 enzyme was measured by spectrofluorometry.

Results

PNS (0.1g/L) significantly increased both BMSC proliferation rate and ALP activity, while it decreased the indicators of oxidative stress, caspase-3 activity, and the apoptosis rate of BMSCs induced by H₂O_2..

Conclusion

PNS, acting as a biological antioxidant, had a protective effect on H₂O₂-induced apoptosis in cultured rabbit BMSCs by decreasing oxidative stress and down-regulating caspase-3.

Objective

To assess the relationship between left ventricular hypertrophy (LVH) or left ventricular geometry (LVG) and endothelial function in patients with essential hypertension (EH).

Methods

Seventy-six patients and 30 normal subjects were first examined by echocardiography. Brachial artery dilatation induced by reactive hyperemia (DIRH) or nitroglycerin (DING) was detected using high-resolution ultrasonography.

Results

DIRH was lower in patients with hypertension than in the controls, and the decrease in DIRH was greater in the patients with LVH than that in patients without LVH (4.36±2.54% vs 8.56±1.87 %; P < 0.0001). There were no significant differences in age, serum concentrations of total cholesterol, triglycerides or sugar, blood pressure and the brachial artery dilatation induced by nitroglycerin between the two groups (P > 0.05). While there was no significant difference in DIRH between the patients with normal left ventricular geometry or cardiac remodeling, the patients showing either eccentric or concentric left ventricular hypertrophy had lower DIRH than the patients with normal left ventricular geometry or cardiac remodeling. The DIRH was the lowest in patients with concentric hypertrophy. Although bivariate analysis showed that the left ventricular mass index (LVMI) correlated well with the brachial artery dilatation induced by reactive hyperemia, diastolic blood pressure and mean blood pressure (r=-0.61, P < 0.0001; r = 0.27, P < 0.05; r = 0.31, P < 0.05, respectively), a multivariate stepwise regression demonstrated that LVMI correlated only with the brachial artery dilatation induced by reactive hyperemia.

Conclusion

Left ventricular hypertrophy was related to endothelial dysfunction in essential hypertension. The endothelial dysfunction might be basic and important in the progression of left ventricular hypertrophy.

Objective

To investigate the effect of the calcium channel blocker verapamil on adipocyte differentiation and its mechanism of action.

Methods

Preadipocytes from 3T3-L1 strain mouse embryos were cultured and differentiated into matured adipocytes in vitro. Verapamil was added to the culture medium in the concentration of 30 μmol/L on Day 0. Cell differentiation was determined by Oil Red O staining and marker gene mRNA expression was evaluated and compared by RT-PCR. The fluo-3/AM probe and laser scanning confocal microscopy were used to measure intracellular calcium concentrations.

Results

Conclusion

In 3T3-L1 preadipocytes verapamil significantly reduced adipocyte differentiation, down-regulated the mRNA expression of three marker genes for adipocytes differentiation, and prolonged the mRNA expression of an inhibitor of differentiation. The inhibitory effect of verapamil on differentiation may involve its role as a blocker of calcium influx in adipocytes.

Objective

To determine the effect of different concentrations of Radix Saposhnikoviae (RS) on the contraction of smooth muscle strips and the Ca²⁺ mobilization of cultured smooth muscle cells of rat colon and its possible mechanism of action.

Methods

Strips of rat colon longitudinal muscle were prepared and smooth muscle cells from rat colon were isolated and cultured. In the experiments, in vitro muscle strips were suspended in an organ bath and the contraction of the strips was recorded. In the cell- experiments, intracellular Ca²⁺ was assessed using fluorescent intensity (FI) of smooth muscle cells loaded with Fluo-4/AM, measured with a laser scanning confocal microscope and related software.

Results

In the in vitro experiment, RS (0.02, 0.2, 2, 20 g/L) inhibited contraction of muscle strips in a concentration-dependent manner, and this inhibition was significant for the three higher RS concentrations (P < 0.01) for both Peak (the maximal contraction amplitude) and Area (the area under curves). Similarly, RS inhibited Ach-induced contraction. In these experiments the inhibition of the Peak values in the RS 2 and 20 g/L groups was significant (P < 0.01), as was the inhibition of the Area values in all RS groups (P < 0.05). Naloxone and propranolol did not significantly affect the inhibitory effect of RS on smooth muscle contractility, while phentolamine significantly reduced the inhibitory effect (P < 0.01). In experiments using primary smooth muscle cell cultures in Ca²⁺ - containing buffer, the post-treatment fluorescence of cells in the RS 0.2, 2 and 20 g/L groups differed significantly from pre-treatment values (P < 0.05), and the percent inhibition of fluorescence in the RS 2 g/L and 20 g/L groups was significant (P < 0.01). However, in Ca²⁺-free buffer, FS had no significant effect on cell fluorescence.

Conclusion

RS inhibited both the spontaneous and Ach-stimulated contraction of rat colonic smooth muscle strips. This RS effect appeared to involve α-adrenoceptors, but not β-adrenoceptors or opioid receptors. In cultured primary smooth muscle cells, RS reduced the mobilization of Ca²⁺ from extracellular sources, but may had no effect on the release of Ca²⁺ from sarcoplasmic reticulum and endoplasmic reticulum.