Chinese medical sciences journal = Chung-kuo i hsueh k'o hsueh tsa chih最新文献

Objective: To observe the long-term impact of calcium phosphate (CaP) sol-gel coating on bone growth around porous-surfaced implant.

Methods: The porous-surfaced Ti-6Al-4V implants were prepared with the addition of a thin film of CaP sol-gel coating, and implanted into the tibiae of 8 rabbits, each with two implants. Implanted sites were allowed to heal for 2, 8, 12, and 24 weeks, after which specimens were obtained for scanning electron microscope analysis using the freeze-fracture technique.

Results: The sol-gel coated implants recovered by freeze-fracture technique showed extensive bone growth from the endosteum along the implant surface. The bone was in direct contact with the CaP layer. The cement line-like layer was clearly demonstrated to be an intervening electron dense afibrillar layer between the CaP coat and the overlying newly deposited bone. The stability and osseointegration of the porous-surfaced implants seemed not to be affected by the osteoclastic resorption of CaP layer occurred during 24 weeks of healing.

Conclusion: Based on the findings in the long-term observation, the addition of a thin layer of CaP promotes an extensive osseointegrated interface between the porous-surfaced Ti-6Al-4V implants and the newly deposited bone.

Objective: To evaluate and reduce inter-observer variations in the detection and characterization of pulmonary nod-ules on digital radiograph (DR) chest images.

Methods: Two hundreds and thirty-two new posterior-anterior DR chest images were collected from out-patient screening patients. Consensus was reached by two experienced radiologists on the marking, rating, and segmentation of small actionable nodules ranged from 5 to 15 mm in diameter using a computer-aided diagnosis (CAD) system. Both their own nodule findings and the computer's automatic nodule detection results were analyzed to make the consensus. Nodules identified together with corresponding likelihood rating and segmentation results were referred as "Gold Standard". Two un-experienced radiologists were asked to first mark and characterize suspicious nodules independently, then were allowed to consult the computer nodule detection results and change their decisions.

Results: Large inter-observer variations in pulmonary nodule identification and characterization on DR chest images were observed between un-experienced radiologists. Un-experienced radiologists could greatly benefit from the CAD system, including substantial decrease of inter-observer variation and improvement of nodule detection rates. Moreover, radiologists with different levels of skillfulness could achieve similar high level performance after using the CAD system.

Conclusion: The CAD system shows a high potential for providing a valuable assistance to the examination of DR chest images.

Objective: To evaluate the efficacy and safety of combination chemotherapy with paclitaxel and carboplatin for advanced breast cancer (ABC).

Methods: From January 2001 to March 2006, 45 patients with ABC were treated with combination chemotherapy of paclitaxel and carboplatin. Patients received infusion of paclitaxel 175 mg/m2 on day 1 every 3 weeks or 75 mg/m2 on day 1, 8, 15 every 4 weeks. Carboplatin was administrated on day 2 with a dose of area under the time-concentration curve (AUC) being 5.

Results: The median number of cycles was 3 (range, 2-6). The overall response rate was 62.2%. Median time to progression was 7.0 months (95% CI: 5.1-8.9). Median overall survival was 29.0 months (95% CI: 20.1-37.9). One year survival rate was 73.3%. Response rate for first line and second line treatment were 62.1% and 62.5% , respectively. No significant difference in response existed between visceral metastasis and soft tissue metastasis. The main side effects included nausea/vomiting, neurotoxicity, and hematologic toxicities. Grade III to IV adverse events included nausea/vomiting in 2 cases (4.4%), leukopenia in 17 cases (37.8%) , and alopecia in 6 cases (13.3%).

Conclusion: Combination of paclitaxel and carboplatin is active in treatment of ABC with an acceptable toxicity profile.

Objective: To evaluate the feasibility and safety of peripheral CD34+ cell mobilization in patients with severe autoimmune disease.

Methods: Forty-two patients underwent a total of 46 mobilizations by the regimen of cyclophosphamide 2-3 g/m2+ recombinant human granulocyte colony stimulating factor (rhG-CSF) 5 microg x kg(-1) x d(-1). The positive selection of CD34+ cell was performed through the CliniMACS.

Results: In 8.1 +/- 2. 3 days after administration of cyclophosphamide, the peripheral white blood cell and mononuclear cell (MNC) decreased to the lowest level. In 3.7 +/- 1.6 days after injection of rhG-CSF, the peripheral absolute MNC and CD34+ cell counts were 0.95 x 10(9)/L and 0.035 x 10(9)/L, respectively. After 2.4 +/- 0.6 times of leukapheresis, there gained 4.46 x 10(8)/kg of MNC and 5.26 x 10(6)/kg of CD34+, respectively. After mobilization, the underlying diseases were ameliorated more or less. In systemic lupus erythematosus (SLE) patients, SLE Disease Activity Index (SLEDAI) decreased from a median of 17 to 3 (P < 0.01). In rheumatic arthritis patients, an American College of Rheumatology criteria for 20% (ACR20) response was achieved in all five patients. Totally, 17.4% of patients whose absolute neutrophil count < 0.5 x 10(9)/L suffered infection, and 31.0% of patients had bone pain after the injection of rhG-CSF. Two patients suffered severe complications, one with acute renal failure and recovered by hemodialysis, the other died of thrombotic thrombocytopenic purpura. Failed mobilization occurred in three patients.

Conclusions: Sufficient CD34+ cells can be mobilized by low dose of cyclophosphamide and rhG-CSF. CD34+ cell mobilization for treatment of severe autoimmune disease not only is appropriate in both effectiveness and safety but ameliorates disease also.

Objective: To investigate the clinicopathological characteristics of advanced colorectal cancer which was 30 mm or smaller in diameter.

Methods: Retrospective analysis documented 80 patients with small advanced colorectal cancer from May 1985 to May 2002. According to the diameter of tumors, all patients were divided into three groups: Group A (10 mm or less), Group B (11-20 mm), Group C (21-30 mm). Considering the number of patients in Group A was smaller, we combined Group A with Group B as Group D. Then various clinicopathological characteristics were compared between Group C and Group D.

Results: The most common site of small advanced colorectal cancer was sigmoid colon and rectum that accounted for 36.2% and 35.0% of all cases. The average diameter of total tumors was 23.3 mm. Type 2 was the most common macroscopic type (63.7%) and the moderate differentiation was seen in 77.5% of cases. Thirty-eight (47.5%) cases had lymph node metastasis. Three (3.8%) cases had liver metastasis and three (3.8%) cases had peritoneal metastasis. The frequency of lymph node metastasis was found significantly different between Group C and Group D (54.2% vs. 28.6%, P < 0.05) , as well as between the groups with different depth of invasion (P < 0.05). Curability A resection was performed in 69 (86.2%) cases.

Conclusions: Tumor size and depth of invasion are related to lymph node metastasis in small advanced colorectal cancer. However, the small size of tumor may not always be a reliable parameter for estimating the risk of lymph node metastasis. Small colorectal cancers also do not always mean the early stage. Surgeons should be aware of the features of small advanced colorectal cancers to select ideal management and perform perfect resection.

Objective: To construct adeno-associated virus (AAV) expression system for transforming growth factor beta3 (TGFbeta3 ) and detect its biological effect on proteoglycan synthesis of the earlier and later dedifferentiated rabbit lumbar disc nucleus pulpous (NP) cells, which was compared with that of adenovirus (AV) expression system for TGFbeta1.

Methods: TGFbeta3 gene was obtained using PCR. Its upstream contained restriction enzyme site Kpn I, and its downstream contained restriction enzyme site Sal I. Using the restriction enzyme sites of PCR product of TGFbeta3 and the corresponding multiple cloning site (MCS) in plasmid AAV, TGFbeta3 was subcloned into AAV. The recombinant plasmid AAV-TGFbeta3 was transfected into H293 cells with Lipofectamine 2000, and the expression of TGFbeta3 gene was detected using immunofluorescent analysis. After AAV-TGFbeta3 virus particle with infectious activity was packaged, TGFbeta3 expression in NP cells was detected by immunoblotting, and its biological effect on proteoglycan synthesis was detected by antonopulos method and compared with that of AV-TGFbeta1 in the earlier and later dedifferentiated NP cells.

Results: For the earlier dedifferentiated NP cells, AAV-TGFbeta3 slowly and stably enhanced proteoglycan synthesis, but AV-TGFbeta1 rapidly and transiently enhanced its synthesis. For the later dedifferentiated NP cells, AAV-TGFbeta3 stably enhanced proteoglycan synthesis, but AV-TGFbeta1 inhibited its synthesis.

Conclusion: AAV expression system can mediate TGFbeta3 gene to be expressed stably, and AAV-TGFbeta3 can enhance proteoglycan synthesis of the earlier and later dedifferentiated NP cells.

Objective: To explore the feasibility and safety of gene transfer into porcine myocardium via the pericardial cavity by a homemade easy device.

Methods: Replication-deficient recombinant adenoviral vector carrying LacZ report gene (Ad-LacZ) was constructed by the calcium phosphate precipitation method. Twelve healthy Chinese mini-swine were randomly divided into experimental group (n = 6) and control group (n = 6). Acute myocardial infarction (AMI) model was established by balloon occlusion of the distal part of D1 branch of left anterior descending (LAD) artery, at the same time the intrapericardial cavity injections were performed through the small incision of the abdominal wall below the xyphoid appendix using a homemade device. Then gene transfer was performed using a central venous catheter. The pericardium was pretreated with injection of a mixture of collagenase (1,200 U) and hyaluronidase (3,000 U) in both groups. Then 2.0 x 10(9) plaque formation unit (PFU) Ad-LacZ was injected into the pericardial cavity in experimental group, while 1 mL of normal saline was injected in the control group. The beta-galactosidase activity detection and X-gal staining of the ischemic myocardium were performed on the 3rd, 7th, and 28th day after injection.

Results: The LAD artery was occluded completely and infarction and ischemia were detected by histological assessment In experimental group, the X-gal staining positive cells and beta-galactosidase activity quantification were detectable on the 3rd day after injection, increased markedly on the 7th day, and then declined on the 28th day. The transfer efficiencies indicated by the positive myocardial cells were 16.7%, 45.6% , 22.8% on the 3rd, 7th, 28th day, respectively. In control group, no positive cells and beta-galactosidase activity were observed.

Conclusion: Adenovirus can be transferred into ischemic myocardium and express target gene in the AMI model for four weeks with the homemade easy device via pericardial cavity pretreated by collagenase and hyaluronidase.

Objective: To investigate the quantities of bone marrow CD5+ B lymphocytes in the patients with autoimmune hemocytopenia and the relationship between quantities of CD5+ B lymphocytes and clinical or laboratorial parameters.

Methods: Quantities of CD5+ B lymphocytes in the bone marrow of 14 patients with autoimmune hemolytic anemia (AIHA) or Evans syndrome, 22 immunorelated pancytopenia (IRP) patients, and 10 normal controls were assayed by flow cytometry. The correlation between their clinical or laboratorial parameters and CD5+ B lymphocytes was analyzed.

Results: The quantity of CD5+ B lymphocytes of AIHA/Evans syndrome (34.64% +/- 19.81%) or IRP patients (35.81% +/- 16.83%) was significantly higher than that of normal controls (12.00% +/- 1.97%, P < 0.05). However, there was no significant difference between AIHA/Evans syndrome and IRP patients (P > 0.05). In all hemocytopenic patients, the quantity of bone marrow CD5+ B lymphocytes showed significantly negative correlation with serum complement C3 level (r = -0.416, P < 0.05). In the patients with AIHA/Evans syndrome, the quantity of bone marrow CD5+ B lymphocytes showed significantly positive correlation with serum indirect bilirubin level (r = 1.00, P < 0.05). In Evans syndrome patients, the quantity of CD5+ B lymphocytes in bone marrow showed significantly positive correlation with platelet-associated immunoglobulin G (r = 0.761, P < 0.05) and platelet-associated immunoglobulin M ( r = 0.925, P < 0.05). The quantity of CD5+ B lymphocytes in bone marrow of all hemocytopenic patients showed significantly negative correlation with treatment response (tau-b = -0.289, P < 0.05) , but had no correlation with colony forming unit-erythroid (r = -0.205, P > 0.05) or colony forming unit-granulocyte-macrophage colonies (r = -0.214, P > 0.05).

Conclusions: The quantity of bone marrow CD5+ B lymphocytes in the patients with autoimmune hemocytopenia significantly increases and is correlated with disease severity and clinical response, which suggest that CD5+ B lymphocytes might play an important role in the pathogenesis of autoimmune hemocytopenia.

Objective: To examine whether ischemic preconditioning (IPC) can protect neuron against delayed death in CA1 subfield of hippocampus following reperfusion of a lethal ischemia in rats, and explore the role of p53 and bax in this process.

Methods: We examined the effect of IPC on delayed neuron death, neuron apoptosis, expressions of p53 and bax gene in the CA1 area of hippocampus in the rats using HE staining, flow cytometry, RT-PCR, and immunohistochemistry technique.

Results: IPC enhanced the quantity of survival cells in the CA1 region of hippocampus (216 +/- 9 cells/0.72 mm2 vs. 30 +/- 5 cells/0.72 mm2, P < 0.01) , decreased the percentages of apoptotic neurons of hippocampus caused by ischemia/reperfusion (2.06% +/- 0.21% vs. 4.27% +/- 0.08%, P < 0.01 ), and weakened the expressions of p53 and bax gene of hippocampus compared with ischemia/reperfusion without IPC.

Conclusion: IPC can protect the neurons in the CA1 region of hippocampus against apoptosis caused by ischemia/reperfusion, and this process may be related to the reduced expressions of p53 and bax.