Changes in the expression of angiotensin II type 1 receptor in the development of liver fibrosis.

OBJECTIVE: To detect the expression of angiotensin II type 1 receptor (AT1R) in the different stages of human liver fibrosis. METHODS: The morphology and ultrastructure of hepatic stellate cells (HSC) in hepatic sinusoids were studied by transmission electron microscopy, collagen I (col I) was tested by immunohistochemical method, an indirect immunofluorescence labeling method was used to detect AT1R, and semiquantitative RT-PCR was used to detect AT1R mRNA. RESULTS: Positive expression of AT1R was mainly distributed in the periphery of hepatic lobules and in the cytoplasm of HSC in the sinusoids. In normal liver tissue from 12 cases, positive expression of AT1R was seen in 8, whereas in 18 fibrotic livers, all showed positive expression. Cells that positively expressed AT1R were significantly more abundant in the fibrotic liver group than in the normal liver group (P < 0.001), and were significantly increased with an increase in the collagenous surface area. The relative expression level of AT1R mRNA in the fibrotic liver group was also higher than in the normal liver group (P < 0.01). CONCLUSIONS: The expressions of both AT1R and AT1R mRNA increased significantly with the degree of liver fibrosis, so angiotensin II and its receptor are probably important in the development of liver fibrosis.

[Development of toxin targeting to VEGF-KDR].

OBJECTIVE: To develop toxin targeting vascular endothelial growth factor receptor II (VEGF-II/KDR) fused with a KDR-binling peptide screened from peptide library. METHODS: By affinity to KDR molecular which expressed specifically by new born vascular endothelial cell, peptides to KDR were screened from C7 peptide library by phage display. Among them, a peptide binding to KDR with high affinity termed as P5 was selected and fused to the N-terminal of Shiga toxin subunit A (StxA). The protein (P5-StxA) was expressed in E. coli. RESULTS: ELISA and Western blot were applied to characterize the binding interaction between the fusion protein, P5-StxA and KDR. Cytotoxicity assay showed that P5-StxA maintained similar toxicity to cell as StxA. In the model of angiogenesis, P5-StxA inhibited selectively VEGF-induced growth of preexisting vessels of the chick chorioallantoic membrane. CONCLUSION: These studies demonstrate the small peptide, P5, maybe be used as carrier of toxin targeting to KDR.

[Pathological and ultramicrostructural changes of tissues in a patient with severe acute respiratory syndrome].

OBJECTIVE: To study the morphological, ultramicrostructural and pathological changes of tissues from a patient with severe acute respiratory syndrome (SARS). METHODS: One autopsy case of diagnosed SARS was investigated. Lung puncture was performed immediately after the patient died, and the autopsy was done after 12 h. The specimens from lymph nodes, spleen, small intestine, colon and bone marrow were studied by immunohistochemical technique. The antibodies used included CD20, CD45RO (UCHL-1), CD4, CD8, CD68 and CD34. RESULTS: The principal lesions of the SARS case consisted of acute lobular intrastitial pneumonia, hyaloid membranes of pulmonic alveoli and hyperplasia and shedding of alveolar epithelium of. Virus-like inclusions occasionally contained cytoplasm of the alveolar epithelium, which were positive by histochemical staining. The adjacent blood-vessels were changed by hyperplasia and enlargement. The structures of lymph nodes and spleen were damaged with lymph follicles depletion and splenic nodules atrophy. The specific changes included reduction of lymphocytes and hyperplasia of histiocytes, depletion of the follicles of small intestine and colon wall, decreased hyperplasia of the bone marrow and increased number of the megakaryocyte. Meanwhile, in the immunohistochemical study, CD(20)(+) B cells were fully expressed in lymph nodes and spleen, and the CD45RO (UCHL-1)(+) T cells were scatteredly expressed. The number of CD4(+) help T cell was markedly decreased, while the number of CD8+ poisonal T cells increased, and the ratio of the former and latter was no more than 0.5. Under the electronic microscopy observation, virus-like particles with 80 - 160 nm diameter and halo or garland envelope were found in mononuclear macrophage and cytoplasm of alveolar epithelium. CONCLUSION: The specific lesions of SARS consist of lobular intrastitial pneumonia with the formation of hyaline membranes of lung, haemorrhage, necrosis, inflammation of blood vessels and the damages of extralung lymphohemopioetic system. The damages were very similar to the pathological features of tissues infected by human immunodeficiency virus, in which numbers of T cells decreased and CD(4)(+) T cell/CD(8)(+) T cell ratio was no more than 0.5. According to the virus-like particles found in lung of the SARS case, it is considered that these virus-like particles may be a new kind of coronavirus which caused the "atypical pneumonia".

[Pathological changes of lungs in patients with severity acute respiratory syndrome].

OBJECTIVE: To evaluate the progression in morphologic changes of lungs in SARS patients. METHODS: Four cases of SARS with lung tissue samples available (including one for ultrastructural examination) were enrolled into the study. Histochemical study for VG, Masson, reticulin, orcein, PAS, sirius red stains and immunohistochemical study for vimentin, desmin, smooth muscle actin, HHF-35, CD34, F8, collagen types I and III were also performed. RESULTS: According to the morphologic changes, lung lesions in SARS were subcategorized into 3 phases: acute exudative inflammation, fibrous proliferation and the final fibrotic stage. Two cases belonged to the acute exudative phase, in which the course was less than 20 days. The principal lesions consisted of acute alveolar exudative inflammation, hyperplasia of alveolar epithelium, necrosis, alveolar hyaline membrane formation, alveolar desquamation and focal fibroplasia. The acute exudative protein was PAS-positive. There was an increase in reticulin fiber formation. The reactive fibroblasts were highlighted by desmin and vimentin. One case belonged to the fibroproliferative stage, in which the course was around 25 days. Major lesions included proliferative interstitial pneumonia with early pulmonary fibrosis. There was also evidence of organizing pneumonia, with an increase in reticulin fiber formation, which had a glomeruloid appearance on special stain. The mesenchymal cells showed either myofibroblastic (which expressed desmin, HHF-35, smooth muscle actin and vimentin) or fibroblastic (which expressed vimentin only) differentiation. Fibroelastosis and fibroplasia was also noted. The remaining case belonged to the fibrotic stage, in which the course was around 75 days. The main features included diffuse fibrosis and honeycomb change, which were highlighted by sirius red stain. Immunohistochemistry showed mainly types I and IV collagen fibers. In all lesions, there was also an increase of number of CD68-positive macrophages. CONCLUSIONS: The morphologic progression in lungs of SARS patients is characterized by the development of increased fibrosis. The primitive mesenchymal cells, hyperplastic alveolar epithelial cells and macrophages play an important role in the pathogenesis.

[Effect of sphingosine-1-phosphate on chemotherapy-induced ovarian damage and on the efficacy of chemotherapy in mice bearing S180 tumor].

OBJECTIVE: To investigate the effects of sphingosine-1-phosphate (S1P) on cyclophosphamid (CTX) and cisplatin (DDP)-induced ovarian damage and on the efficacy of chemotherapy in mice bearing S180 murine sarcoma. METHODS: Fifty-two female C57BL/6 mice were randomized into normal control group (n=10), tumor-bearing model group (n=14), CTX+DDP group (n=14), and S1P+CTX+DDP group (n=14). Before medication and on day 11 of medication during diestrus stage, the mice were sacrificed to measure the ovarian weight, numbers of primordial follicles and growing follicles, tumor weight, and serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH) and estradiol ( E2). RESULTS: At day 11 of medication, the levels of serum FSH and E2, but not LH, showed significant differences in CTX+DDP group from those in the other groups (P<0.01). FSH, E2, and LH levels were comparable between S1P+CTX+DDP group and the control group (P>0.05). The number of primodial follicles and weight of ovaries in CTX+DDP group decreased significantly compared to those in the other groups (P<0.01). The number of growing follicles in CTX+DDP group was significantly lower than that in the control and model groups(P<0.01), but similar to that in S1P group (P>0.05). The number of primodial follicles and growing follicles and ovarian weight in S1P+CTX+DDP group were close to those in the control and model groups (P>0.05). In CTX+DDP and S1P+CTX+DDP groups, the tumor weight were significantly lower than that in the other two groups (P<0.01), and the tumor inhibition rates were both higher than 60%. CONCLUSION: S1P can ameliorate chemotherapy-induced ovarian damage in mice without affecting the efficacy of chemotherapy.

[Effects of gonadotroph-releasing hormone analogues on follicle apoptosis in rats with chemotherapy-induced ovarian damage].

OBJECTIVE: To study the effects of gonadotroph-releasing hormone (GnRH) agonist (GnRH-a) and GnRH antagonist (GnRH-ant) on cyclophosphamide (CTX)-induced follicle apoptosis in female rats. METHODS: Thirty-six female Sprague- Dawley rats were randomized into 6 groups, namely normal saline (NS), CTX, GnRH-a+NS, GnRH-a+CTX, GnRH-ant+NS, and GnRH-ant+CTX groups. The rats were sacrificed between the first and second week after the treatments., and the follicle apoptosis was investigated using TUNEL assay and transmission electron microscopy. RESULTS: The apoptosis rate of the granulose cells in the follicles in late development was significantly higher than that in early follicles, and the apoptosis rate of the oocytes and granulose cells in rats with CTX treatment was significantly higher than that in rats without CTX treatment (P<0.05). The apoptosis rate of the granulose cells in GnRH-a groups (ranging from 33.40 - or + 4.59 to 73.25 - or + 5.35) was significantly higher than that in GnRH-ant groups (27.46 - or + 4.52 to 49.38 - or + 5.02, P<0.05), but there was no significant difference in the oocytes of early follicles between GnRH-a groups (23.48 - or + 4.25 to 36.15 - or + 4.23) and GnRH-ant groups (21.47 - or + 3.81 to 34.04 - or + 5.54, P>0.05). Electron microscopy revealed characteristic apoptotic changes of the oocytes in early follicles and granulose cells in early and late follicles. The apoptotic changes were especially typical in the granulose cells showing the formation of the apoptotic bodies, and the oocytes only showed chromatin condensation and aggregation. CONCLUSION: In the rat mode, GnRH-a promotes while GnRH-ant suppressed follicle apoptosis induced by CTX. GnRH analogues regulates mainly granulose cell apoptosis, but have little effect on oocyte apoptosis.

[Effect of alexandrite laser treatment for hair removal in Tibet mini-pigs].

OBJECTIVE: To observe the histological and ultrastructural changes of the skin and hair follicles following hair removal by alexandrite laser in Tibet mini-pigs. METHODS: Twelve healthy Tibet mini-pigs with dark hair were treated with alexandrite laser for hair removal. The skin specimens were taken immediately and at 1 h and 1, 3, 5, 10, 15, 30, 60 days after the laser treatment for observation under optical and transmission electron microscope. RESULTS: Laser hair removal resulted in extensive coagulation necrosis, carbonization and falling of the subcutaneous hair shafts, and some of the cells in the outer root sheath and hair bulb underwent degenerative and necrotic changes. One hour after laser treatment, the cells in the outer root sheath and bulb exhibited nuclear condensation, fragmentation and or karyolysis characteristic of cell apoptosis. The cell apoptosis reached the peak level on day 3 after the laser exposure, accompanied by endothelial degeneration in the hair papilla vessels, edema and lymphocyte infiltration in the dermal tissues. Tissue reaction and inflammation were relieved on day 5, and the dermal tissue and follicles recovered their normal structures on day 10. At 60 days after the treatment, the hair follicles decreased markedly but the structure of the residue follicles remained normal. CONCLUSION: Alexandrite laser exposure results in selective destruction of the follicles by inducing direct coagulation and cell apoptosis to achieve permanent hair removal. Tibet mini-pigs with black hair can be used as the animal model of clinical laser hair removal.

[Relationship between fluorodeoxyglucose uptake and vascular endothelial growth factor in early-stage nasophygeal carcinoma].

OBJECTIVE: To study the overexpression of vascular endothelial growth factor (VEGF) and fluorine-18 fluorodeoxyglucose (FDG) uptake in early-stage nasopharyngeal carcinoma (NPC) and evaluate their relationship. METHODS: FDG positron emission tomography (PET) was performed in forty patients with stage I and stage II NPC. The maximum and mean standard uptake values (SUVmax and SUVmean, respectively) were measured in each patient, and the expression of VEGF was measured on paraffin sections using immunohistochemistry. RESULTS: The FDG uptake in the patients were 9.45-/+1.87 (SUVmax) and 6.04-/+1.09 (SUVmean), 8.95-/+1.91 (SUVmax) and 6.04-/+1.09 (SUVmean) in stage I patients, and 11.55-/+1.70 (SUVmax) and 7.98-/+1.1 (SUVmean) in stage II patients. The FDG uptake of stage II patients was higher than that of stage I patients. The FDG uptake of non-keratinizing differentiated carcinoma was 9.74-/+1.82 (SUVmax) and 6.82-/+1.23 (SUVmean) and 10.44-/+2.16 (SUVmax) and 6.68-/+1.35 (SUVmean) in non-keratinizing undifferentiated carcinoma, showing no significant differences between them (SUVmax: t=1.230, P>0.05; SUVmean: t=0.346, P>0.05). The VEGF-positive cells were 60.80% in the tumor. A correlation between VEGF expression and FDG uptake in he tumor was noted (r=0.460, P=0.03). CONCLUSION: VEGF overexpression is correlated to FDG uptake in patients with early-stage NPC. The SUV value reflects the glucose metabolism of NPC, and also shows the degree of oxygen insufficiency in the tumor tissue.

Morphological observation of nuclear sub-localization of human angiogenin in HUVECs.

Angiogenin, a potent angiogenic factor, was cloned and expressed by Escherichia coli and then purified with gel filtration chromatography. Approximately 90% pure angiogenin was obtained to generate a monoclonal antibody. Using western immunoblotting and ELISA, we confirmed that monoclonal antibody C46 secreted from hybridoma cells stably and specifically binds to angiogenin. The fused protein angiogenin-EGF was then expressed in HUVECs, and the subcellular localization of the recombinant protein was determined by confocal microscopy and TEM assay. Recombinant angiogenin was found to mainly concentrate in the pars granulosa of the nucleus, where the protein accumulates to form ribonucleoprotein particles.

[Effect of GnRH analogs on the expression of Bcl-2 gene family in the ovary of rats with cyclophosphamide-induced ovarian damage].

OBJECTIVE: To study the effect of gonadotroph-releasing hormone (GnRH) agonist (GnRH-a) and GnRH antagonist (GnRH-ant) against cyclophosphamide (CTX)-induced gonadotoxicity in female rats. METHODS: Thirty-six female SD rats were divided randomly into 6 groups to receive treatment with normal saline (NS), CTX, GnRH-a+NS, GnRH-a+CTX, GnRH-ant+NS, GnRH-ant+CTX, respectively. The rats were sacrificed between the first and second week after termination of the medication to compare the weight of the ovaries, the number of the primordial follicles and the follicle growth. The expressions of bcl-2 and bax mRNA in the ovaries were examined using RT-PCR. RESULTS: The number of the primordial follicles was significantly greater and that of the growing follicles significantly lower in GnRH-a+NS and GnRH-a+CTX groups than in the GnRH-ant+CTX and CTX groups (P<0.05). The rats in GnRH-a+NS and GnRH-a+CTX groups had the lowest ovarian weight among 6 the groups (P<0.05). The bcl-2 mRNA level in the GnRH-ant+NS group was significantly higher than that in the other groups (P<0.05). The Bax mRNA in the GnRH-a+NS and GnRH-a+CTX groups was significantly higher than that in the NS group (P<0.05), but close to that in the CTX group (P>0.05); bax mRNA expression in the GnRH-ant+NS group was significantly lower than that in the NS group (P<0.05), but in GnRH-ant+CTX group, its expression was close to that in the NS group (P>0.05). CONCLUSIONS: In female rats exposed to CTX, the GnRH analogs provides ovarian protection against CTX-induced gonadotoxicity by regulating the expression of the Bax mRNA in the ovary. GnRH-a may decrease the sensitivity of the follicles to CTX-induced gonadotoxicity by promoting follicle apoptosis and inhibiting follicle proliferation, and GnRH-ant increases the sensitivity to the CTX through a reverse effect on the follicles.

[Construction of recombinant vector pEGFP-ANG and expression of angiogenin gene in HUVECs].

AIM: To express the recombinant angiogenin protein in mammalian cells. METHODS: Human ANG full-length cDNA was obtained by chemical synthesis. The target gene ANG was inserted into eukaryotic expression vector pEGFP-C2. The recombinant plasmid was transfected into the human umbilical vein endothelial cells (HUVECs) via Lipofectin transfection. The expression of ANG gene in transfected HUVECs was detected by fluorescence microscopy and immunohistochemical staining. RESULTS: DNA sequencing showed the sequence of the synthetic ANG was correct and amino acid sequence of ANG was right. The green fluorescence could be seen in transfected HUVECs under fluorescence microscope. Immunohistochemical staining detection showed that ANG expressed in transfected cells. CONCLUSION: Human ANG full-length cDNA has been obtained. The ANG protein was expressed in mammalian cells successfully.