Volume 115  ·   Issue 12  ·  2002

Objective To identify genotype of eight strains of Orientia tsutsugamushi (O. tsutsugamushi) isolated from Nan Peng Lie Islands in China and establish tsutsugamushi disease nature foci for this region. Methods The nested polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) were used. Three primers were selected from the DNA sequence of the gene encoding type-specific 56-kDa protein of the Karp strain. The positive products were digested by Hinell and Pstl, meanwhile profiles specific to each strain were analyzed. Results Three genotypes of O. tsutsugamushi including Karp, Kato and a new strain existed on Nan Peng Lie Islands. Conclusion Nan Peng Lie Islands is tsutsugamushi disease nature foci. Chin Med J 2002; 115(12): 1881-1882

Objective To study the application of dental implant distractor (DID) in mandibular functional reconstruction. Methods We designed a new device named DID, which includes the permanent dental implant and the temporary distractor in itself. It is specially designed for fibula wider distraction in mandible reconstruction. Twenty-five sets of DID devices were put into 8 patients (6 men and 2 women) during operation. Two patients suffered from ameloblastoma of the mandible, 2 from odontogenic cyst of the mandible, 1 from fibrous dysplasia, and the other 3 from malignant tumor of the mandible. The age of 8 patients ranged from 19 to 67 (mean 46.8) years. Results During postoperative 2-15 months follow up, 7 patients were found to be successful. The clinical examination and X-ray film showed the normal shape of the mandible and the osteointegration of the implants were solid enough to withstand the denture force. Others had the DID removed because of inflammation. Two of the patients successfully worn the fixed dental prosthesis. The outcomes was satisfying. Conclusion The DID device specially designed for mandibular reconstruction with fibular flap can help to simplify convenient procedures to a single surgery. Chin Med J 2002; 115(12): 1877-1880

Objective To evaluate the value of magnetic resonance imaging (MRI) and three dimensional (3D) contrast magnetic resonance angiography (MRA) in the diagnosis of complications of simultaneous pancreas-kidney transplantation (SPKT), as confirmed by biopsy and digital subtraction angiography (DSA). Methods Five MR examinations of five patients were performed within 28 days to 2 years after surgery on GE 1.5T MR system. Imaging techniques included axial and sagittal chemical fat-suppressed T1-weighted image (T1WI) and T2-weighted image (T2WI), additional contrast axial or saggital chemical fat-suppressed T1WI were obtained after 3D contrast MRA for calculating the mean percentage of the parenchymal enhancement (MPPE) of the pancreas and kidney. 3D contrast MRA was performed with Smartprep technique. MRA data were analyzed with maximum intensity projection (MIP) and multi-planner reformat (MPR). Results In five cases of transplant pancreases, MRI found two normal pancreas grafts, one case of acute rejection, one case of chronic rejection with 70% fibrosis and one case of late pancreatitis. In five transplant kidneys, MRI detected four normal kidney grafts and one case of acute rejection with infarction. MPPE could distinguish infarction from other complications. 3D contrast MRA could display vascular complications of SPKT, such as stenosis or occlusion, aneurysm formation of transplanted vessels and narrowing at the site of anastomosis, as confirmed by DSA. Conclusion With combined application of MRI and 3D contrast MRA, complications of SPKT can be clearly identified. Chin Med J 2002; 115(12): 1868-1872

Objective To study the potential and advantages of internal distraction osteogenesis in mandibular functional reconstruction. Methods Three types of mandibular distractors were used in eight patients with various mandibular defects due to tumor or cyst resection. The average age of the patients was 31.5 years old (ages ranged from 8 to 54 years). For two patients with ramus defects, specially designed distractors were used to restore the normal ramus height. In two other patients, specially designed trifocal distractors were used. In three patients, vertical distractors were used. Results All the mandibles were successfully reconstructed in accordance with the direction and distance designed before operation except in one patient. In that patient the distal 23 mm defect failed to be corrected because of loosening of transport block fixation screws. Conclusions Mandibular defects can be successfully corrected using internal distraction osteogenesis. Performing mandibular reconstruction using distraction osteogenesis is best done at the time of tumor or cyst resection. Chin Med J 2002; 115(12): 1863-1867

Objective To evaluate the effects of aloin, cinnamic acid and 15 other kinds of natural chemicals on the activity of tyrosinase, in order to provide lightening agents in the treatment of hyperpigmentation disorders and cosmetic additives. Methods Tyrosinase activity was estimated by measuring the oxidation rate of L-dopa. Inhibition of the enzyme was deduced according to the Lineweaver-Burk plots compared to the control. Results Cadabine, paeonal, farrerol, evodin, cinnamic acid, aloin and sophorcarpidine had different levels of inhibition of tyrosinase. The inhibitory rates of cinnamic acid (2 mmol/L, 0.5 mmol/L), aloin (2 mmol/L) and the rest were significantly higher than that of hydroquinone (0.5 mmol/L) (P < 0.05). Conclusions Tyrosinase activity can be greatly inhibited by cinnamic acid, aloin and sophorcarpidine, of which sophorcarpidine functions as an uncompetitive inhibitor, compared to aloin and cinnamic acid, which are mixed-type inhibitors. Chin Med J 2002; 115(12): 1859-1862

Objective To study the effect of polysaccharide sulfate 916 (PS916) on neutrophil-endothelial cell adhesion. Methods Cell adhesion was evaluated by testing neutrophil myeloperoxidase activity. Expression of adhesion molecule in human umbilical vein endothelial cell (HUVEC) was measured by ELISA. The neutrophil activation rate induced by N-formyl-methionyl-leucyl-phenylalanine (fMLP) was tested by nitroblue tetrazolium (NBT) reduction. Results Tumor necrosis factor alpha (TNFα, 50 - 800 U/ml) increased the adherence of neutrophil to TNFα-stimulated HUVEC in a concentration and time dependent manner. PS916 (0.01 -1.0 mg/ml) dose-dependently inhibited the adherence of neutrophils to TNFα-stimulated HUVEC. fMLP increased the activation rate of neutrophils independent of concentration. PS916 also inhibited the adherence of fMLP-activated neutrophils to HUVEC. Moreover, PS916 inhibited adhesion molecule expression in TNFa-stimulated HUVEC. Conclusions PS916 inhibited neutrophil-endothelial adhesion. The mechanism of its action was partially related to suppressing the expressions of intercellular adhesion molecule-1 (ICAM-1) and vascular adhesion molecule-1 (VCAM-1). Chin Med J 2002; 115(12): 1855-1858

Objective To evaluate the efficacy and safety of meropenem in Chinese patients, we conducted a study for the treatment of patients with lower respiratory tract infections, urinary tract infections and other infections. Methods A total of 182 hospitalized patients were enrolled in the study. 90 patients received 500 mg meropenem every 12 hours (or 1 g every 12 hours if necessary) and 92 patients received imipenem/cilastatin 500 mg/500 mg every 12 hours (or 1 g every 12 hours if necessary) by intravenous infusion. The duration of treatment was 7-14 days for both groups. Results Seventy of 90 cases receiving meropenem and 70 of 92 cases receiving imipenem/cilastatin were assessable for clinical efficacy. The overall efficacy rates were 90% for the meropenem group and 87% for the imipenem/cilastatin group, and the bacterial eradication rates were 86% in both groups. 93 (76%) of 123 strains isolated from patients produced β-lactamases. Adverse drug reactions were evaluated in 72 cases in the meropenem group and 70 cases in the imipenem/cilastatin group. The adverse drug reaction rates were 9.7% and 8.6%, respectively. The results showed that there were no statistical differences between these two groups (P > 0.05). Conclusion Meropenem is effective and safe for the treatment of bacterial infections caused mainly by beta-lactamase-producing strains. Chin Med J 2002; 115(12): 1849-1854

Objective To investigate the effect and mechanism of the antihyperglycemic agent metformin on the expression of phosphoenolpyruvate carboxykinase (PEPCK) gene in hepatocytes and to determine whether the effects of metformin in hepatocytes are transmitted throughout the known insulin signaling pathways. Methods Confluent H4IIE rat heptoma cells were cultured for 16 h with 0.1 mmol/L metformin either in absence or presence of 0.1 nmol/L insulin, and then stimulated with various agents. The expression of PEPCK gene was examined by Northern blot analysis. Results Therapeutic concentrations of metformin significantly inhibited basal PEPCK mRNA expression and also decreased cAMP and dexamethasone induced PEPCK gene expression through interaction with insulin. In the presence of insulin signaling pathway inhibitors wortmannin and U0126, metformin reduced PEPCK mRNA levels, but wortmannin blocked inhibitory regulation of insulin on PEPCK gene expression. Conclusion Metformin inhibits PEPCK gene expression via either an insulin-independent or an interacting-with-insulin manner. The results suggest that a possible mechanism by which metformin reduces gluconeogenesis could be associated with the inhibition of PEPCK gene expression. Chin Med J 2002; 115(12): 1843-1848

Objective To examine interleukin-8 (IL-8) mRNA expression induced by flow shear stress in human umbilical vein endothelial cells (HUVECs) and investigate its transcriptional activation. Methods Flow laminar shear stress 4.2 dyne/cm2 was used for the stimulating experiments. The flow shear stress-induced IL-8 mRNA expression was detected by reverse transcription-polymerase chain reaction (RT-PCR). pEGFP1 was used to construct IL-8 reporter gene pEGFP1-IL8USCS for determining IL-8 gene transcriptional activation through gene transfer and flow cytometric analysis. NF-κB nuclear translocation was observed by immunocytofluorescent staining. Western blot was used to examine IκB phosphorylation and degradation. RT-PCR, Northern blot, immunocytofluorescent staining and laser confocal microscopy were used to determine Toll-like receptor-4 (TLR-4) expression at mRNA and protein levels in the cells. Results There was a marked increase in IL-8 mRNA expression in HUVECs after 120 min of exposure to laminar flow shear stress. When exposed to shear stress for 180 min, there was an increase in enhanced green fluorescent protein expression in pEGFP1-IL8USCS-transfected endothelial cells. NF-κB p65 immunocytofluorescent staining of HUVECs showed that when exposed to the same flow shear stress for 30 or 60 min, the cell nuclei became stained; after 90 or 120 min, the staining became much more pronounced. A significant increase in P-IκB in the cell lysates occurred after 10 min of exposure while blot density dramatically dropped after 60 min of exposure. The density of the IκB blot dropped with increasing exposure time after 30 min. TLR-4 was present on the surface of HUVECs. HUVECs constitutively expressed TLR-2 and TLR-4 mRNA; when exposed to flow shear stress for 60 min, TLR-4 mRNA expression increased. Conclusion NF-κB activation is involved in flow shear stress-induced IL-8 mRNA expression in human umbilical vein endothelial cells. TLR-4 receptor for innate immunity most likely mediate these events. Chin Med J 2002 ; 115(12): 1838-1842

Objective To investigate the relationship between sleep apnea hypopnea syndrome (SAHS) and some cardiovascular abnormalities in elderly snorers, as well as the effectiveness of nasal continuous positive airway pressure on those with SAHS. Methods With the use of polysomnography, 73 elderly snorers (older than 60 years) were examined and placed into either the SAHS group or the control group. Using ambulatory electrocardiogram (ECG) and blood pressure measurement, daily nocturnal rhythm of blood pressure, hypertension, heart rate variability, some arrhythmia and angina pectoris of coronary heart disease (CHD) were monitored and compared between the two groups before and after 5-7 days of treatment with nasal continuous positive airway pressure on the SAHS group. Results This study indicated a higher incidence (47.9%) of sleep apnea syndrome in elderly snorers and demonstrated that there was a significantly higher incidence of hypertension, disappearance in daily nocturnal rhythm of blood pressure, poor effectiveness of nitrate on angina pectoris of coronary heart disease, decreased heart rate variability during sleep, increased arrhythmia and lower pulse oxygen saturation (Sp02) levels in the SAHS group than in the control group. After nasal continuous positive airway pressure treatment during sleep, snoring control, significantly higher Sp02 levels and lower index of apnea/hypopnea were achieved in the SAHS group; heart rate variability (HRV) and blood pressure day nocturnal rhythm were returned to normal levels. Conclusion This research suggests that there is a close relationship between the development of sleep apnea syndrome and some cardiovascular diseases. Continuous positive nasal airway pressure is effective not only on SAHS but also on coexisting cardiovascular disorders. Chin Med J 2002; 115(12): 1829-1832

Objective To compare the detection rates of Epstein-Barr virus (EBV) DNA in the serum/plasma between apparently healthy adults (AHAs) and nasopharyngeal carcinoma (NPC) patients in attempt to evaluate the efficiency of EBV DNA assay for serodiagnosis of NPC. Methods The plasma and serum were obtained from 58 AHAs and 66 untreated NPC patients. EBV DNA W-fragment was detected using nested ploymerase chain reaction (PCR). Immunoenzymatic assay for titration of IgA-VCA was also adopted. Results EBV DNA detection rate (84.85%) in the plasma/serum of 66 NPC patients was significantly higher than that (10.34%) in 58 AHAs. The sensitivity of plasma/serum EBV DNA assay (0.8485) was higher than that (0.8030) of titrating IgA-VCA (positive criterion≥ 1 :40) though the specificities of these two tests were the same (0.8966). The correct rate, predictive value of a positive test, and Odds ratio of dual positivity (0.8387, 0.9792 and 141.0, respectively) were higher than those of single positivity either to plasma/serum EBV assay (0.5242, 0.7333 and 1.1423, respectively) or to IgA-VCA≥ 1 : 40 test (0.4839, 0.5385 and 1.0480, respectively). Conclusion The EBV DNA detection in the plasma/serum using nested PCR may be a useful indicator for serodiagnosis of NPC. Chin Med J 2002; 115(12): 1895-1897

Objective To investigate the manifestation of clinical, blood routine and bone marrow smear of disseminated penicilliosis marneffei. Methods There were 13 cases of penicilliosis marneffei whose peripheral blood had been drawn for routine tests, as well as blood and bone marrow aspiration for smears. Wright's-Giemsa stain, Gomori's methenamine-silver stain (GMS) and periodic acid Schiff's reaction (PAS) were performed for light microscopy in consultation with pathologic diagnosis and fungi culture for precise diagnosis. Results Seven cases of bone marrow and 2 peripheral blood smears were found positive for penicillium marneffei in the test group. The morphology of penicillium marneffei was extremely similar to that of histoplasma capsulatum. However, the observation of sausage cells and central cross wall, which are signs of dividing by fission and not by budding, aided in differential diagnosis. Conclusion Bone marrow smear or occasional blood smear examination play an important role in the diagnosis of disseminated penicilliosis marneffei. Chin Med J 2002; 115(12): 1892-1894

Objective To visualize epicardial and intramyocardial coronary blood flow by using a noninvasive echocardiography system. Methods In five juvenile swines, coronary flow imaging was used to visualize the different segments of epicardial coronary and intramyocardial arteries. Pulsed-Doppler spectrums were recorded and analyzed. The left anterior descending artery (LAD) and intramyocardial coronary blood flow signals were recorded at baseline and during dipyridamole administration. Results Epicardial and intramyocardial coronary arteries could be visualized by coronary flow imaging. The systolic component of coronary flow in the right coronary artery (RCA) was greater than in the LAD. The intramyocardial blood flow was characterized by persistent retrograde blood flow velocity during systole. Vasodilation with dipyridamole produced exaggerated differences in the phasic pattern of coronary blood flow in epicardial and intramyocardial vessels. Conclusion Color Doppler coronary flow imaging provides a noninvasive method to study the coronary blood flow. Chin Med J 2002; 115(12): 1889-1891

Objective To study the relationship between insulin sensitivity and diffuse coronary artery disease. Methods Ninety-two consecutive patients underwent coronary angiography were enrolled in the study. Relationships between the results of angiograms and both glucose tolerance and blood lipids were analyzed. Results The mean age of the 92 patients (70 males, 22 females) was 65.4 ± 6.3 y. In the 78 patients diagnosed by angiography as coronary artery disease, diffuse lesion was more common in diabetic patients than in those without a diabetes history (12/13 vs 24/65, P = 0.00026). Fasting glucose [(6.06 ± 2.43) × 10-3 mol/L vs (4.80 ± 1.47) × 10-3 mol/L, P = 0.009], glucose levels at one hour [(12.37±4.38) × 10-3 mol/L vs (9.10±3.97) × 10-3 mol/L, P = 0.001], two hours [(11.12 ± 5.64) × 10-3 mol/L vs (7.49 ± 4.29) × 10-3 mol/L, P = 0.003] and three hours [(8.11 ± 5.51) × 10-3 mol/L vs (5.56 ± 3.46) × 10-3 mol/L, P = 0.020] after food were higher in patients with diffuse coronary disease than in those with non-diffuse coronary disease. Differences in the insulin sensitivity index (ISI) between the two groups was statistically significant ( - 4.36 ± 0.52 vs - 3.89 ± 0.69, P = 0.003). The incidence of multiple-vessel disease in diabetic patients was higher than that in non-diabetic patients (12/13 vs 33/65, P = 0.00565). Glucose levels at two hours [(10.22 ± 5.57) × 10-3 mol/L vs (7.67 ± 4.43) × 10-3 mol/L, P = 0.034] and three hours [(7.90 ± 5.47) × 10-3 mol/L vs (5.22 ± 2.79) × 10-3 mol/L, P = 0.007] after food were higher in patients with multiple-vessel disease than in those with single-vessel disease. Impaired insulin sensitivity without a history of diabetes mellitus was commonly seen in patients with coronary artery disease. Conclusions The diffuseness of coronary artery disease is associated with insulin sensitivity and blood glucose levels. Insulin resistance is a common phenomenon in non-diabetic patients. Chin Med J 2002; 115(12): 1886-1888

Objective To evaluate the clinical efficacy of interventional therapy in the treatment of hepatocellular carcinoma (HCC). Methods Thirty-three patients with HCC were synthetically treated by systematic measures. Among them, percutaneous port-catheter system (PCS) implantation via the femoral artery was performed in 21 cases. Patients with haemorrhage were treated with prothrombin complex concentrate and fibroraas, and patients with hepatic encephalopathy by branched-chain amino acids and arginine. Results All indwelling catheters of PCS were patent and no catheter tip dislocations were observed. Of 33 patients with advanced HCC, the mean survival rate was 20.1 months and 12 (36%) patients survived more than 2 years. Conclusion Patients with advanced HCC were treated by synthetic measures. Survival was prolonged, quality of life was improved significantly, and the effectiveness of interventional therapy was further improved. Chin Med J 2002; 115(12): 1883-1885