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Volume 0 ， Issue 1 ， 1998
- Abstract：A library of 2 ×107 random octapeptides was constructed by use of phagemid-based monovalent phage display system. The randomly synthesized degenerated oligodeoxyribonucleotides （oligos ） were fused to the truncated g Ⅲ （p230-p403）. Sequence analysis of 11 randomly chosen clones suggested that the degenerated inserts and its deduced amino acid （aa） sequences are randomly distributed. The library was used to select binding peptides to the monoclonal antibody （mAb） 9E10, which recognizes a continuous decapeptide epi- tope of denatured human c-myc protein. After four to five rounds of panning, most of the eluted clones could bind to 9E10. Sequence analysis of the selected positive clones indicated that the binding sequences could fall into two classes, one class （clone 1） shares a consensus motif, ISE x x L, with c-myc decapeptide; and the sequences of the other class are entirely different. The binding of both classes to 9E10 could be specifically inhibited by free c-myc decapeptide. The immunogenicity of the phage peptide was further investigated by construction of multivalent displayed phage peptides and immunization of animals with or without adjuvant. ELISA and competitive ELISA showed that anti-serum from both mice and rabbit immunized with either clone could bind to the original antigen, c-myc decapeptide. These results denote that in spite of the dissimilarity of the selected peptides with c-myc decapeptide, they are capable of inducing similar immune respones in vivo, thus actually mimicking the antigen epitope.Keywords：monovalent phage display;peptide library;epitope mimicry4|14|0Updated：2024-04-10
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- Abstract：All mammalian metallothionein genes studied to date have several metal responsive elements （MRE） with consensus sequences of TGCRCNC （R, purine） in their regulatory region. MRE-like sequences were also found in many other metal-related genes. To see whether there is also such a sequence at the genetic locus （13q14. 3） of Wilson disease, which is a genetic disorder of copper metabolism, junction-trapping method based on the MRE sequence was used. A fragment containing MRE and MRE-like sequences from YAC 27D8 at the WND locus was successfully cloned and mapped back to the YAC by PCR. Presence of such a sequence in the copper transporter gene at the WD locus might imply that it has a possible interesting role in the regulation of WD gene expression.Keywords：metal responsive element （MRE）;Wilson disease;junction-trapping4|5|0Updated：2024-04-10
- Abstract：O6 -methylguanine- DNA- methyltransferase （MGMT ） plays a very important role in the cellular resis- tance to nitrosoureas drugs. Inhibition of MGMT might be a useful approach in tumor chemotherapy. In this study, the depletion of MGMT activity by retroviral-mediated antisense RNA transfection were reported. Three retroviral vectors expressing MGMT antisense RNA were constructed and transfected into HeLa S3 cells. The difference of MGMT mRNA, MGMT activity as well as cellular resistance to ACNU before and after transfection were observed. It was found that antisense RNA targeting 5’region and whole length of MGMT mRNA could partially deplete MGMT activity and enhance killing effects of ACNU. However, 3’ region antisense RNA had no effect on MGMT modulation.Keywords：MGMT;ACNU;antisense RNA4|21|3Updated：2024-04-10
- Abstract：Apoptosis of nucleated cells is well known, but how about the unnucleated cells is still not elucidated. In the present paper, the morphological and biochemical features of the aged erythrocytes were observed and compared with the characteristic events of apoptosis. Membrane of aged erythrocytes tends to shrink, protrude, from vesicle and lose lipid asymmetry. Aged erythrocytes were removed by phagocytosis. Both of the events are very similar to the apoptotic nucleated cells. The authors suggested that aging of erythro- cytes is also a process of apoptosis.Keywords：aged erythrocytes;apoptosis4|8|0Updated：2024-04-10
- Abstract：A hammerhead ribozyme which site-specifically cleaved the GUC position in canon 880 of the mdr1 mRNA was designed. The target site was chosen between the two ATP binding sites, which may be important for the function of the P-Gp as an ATP-dependent pump. A DNA sequence encoding the ribozyme gene was then incorporated into a eukaryotic expression vector （pH Apr-1 neo） and transfected into the breast cancer cell line MCF-7/Adr, which is resistant to adriamycin and expresses the MDR phenotype. The ribozyme was stably expressed in the cell line by the RNA dot blotting assay. The result of Northern blot assay showed that the expressed ribozyme could decrease the level of mdrl mRNA expression by 83. 5 %; and the expressed ribozyme could inhibite the formation of p-glycoprotein detected by immuno- cy-tochemistry assay and could reduce the cell’s resistance to adrimycin; this means that the resistant cells were 1 000-fold more resistant than the parental cell line（MCF-7）, whereas those cell clones that showed ribozyme expression were only 6-fold more resistant than the parental cell line. These results show that a potentially useful tool is at hand which may inactivate MDR1 mRNA and revert the multidrug resistance phenotype.Keywords：hammerhead ribozyme;multidrug resistance reversion;human breast cancer cell line MCF-7/Adr4|16|0Updated：2024-04-10
- Abstract：Objective. To observe the possibility of maternal-fetal vertical transmission of human papillomavirus （HPV）via amniotic fluid. Subjects and methods. Specimens of cervical secretions from 30 pregnant women were obtained during the third trimester before rupture of membrane, and specimens of pharyngeal secretions of their neonates were obtained 12-48 h after birth. Amniotic fluids were collected in 13 pregnant women during cesarean section. The presence of HPV types 6, 11, 16, 18, 31, 33, 35, 38 deoxyribonucleic acid were detected by consensus polymerase chain reaction. Results. HPV deoxyribonucleic acid was found in 16 cervical secretions, 14 pharyngeal secretions and in 3 amniotic fluids, the positive rate was 53. 3%, 46. 7%, 23. 1 % respectively. The pharyngeal secretion was also HPV positive in one of the three neonates from the amniotic fluid positive mothers. Conclusion. The results indicate that HPV can be transmitted in utero through amniotic fluid and cesarean section can not protect the neonates against vertical transmission completely.Keywords：papillomavirus;polymerase chain reaction;pregnancy4|6|0Updated：2024-04-10
- Abstract：Objective. To determine the effects of losartan and captopril treatment on ventricular remodeling and function after myocardial infarction in rats. Methods. Thirty-two rats with MI induced by coronary ligation after seven days were divided into four groups randomly and treated with captopril（2 g. liter-1, group A）, losartan（10 mg. kg-1. d-1, group B）, losartan（30 mg. kg-1. d-1,group C） and placebo （no drug, group D） for six weeks, respectively. Shamoperated rats（group E）served as controls. Echocardiography was performed at 1 and 7 weeks after MI, re- spectively. Results. Compared with the results before treatment,both LV end-diastolic internal diameter and volume decreased significantly and the thickened Posterior wall was reversed in group A, B and C; the peak early filling velocity decreased whereas the peak velocity was increased in these three groups. There are no significant difference among the three treated groups. However,LV end-diastolic internal diameter and the E/A were still increased,whereas the thickness of anterior wall and the peak velocity of LV outflow were decreased in group A,B,and C after treatment comparing with group E. Conclusion. Both angiotensin converting enzyme inhibitor and angiotensin II receptor antagonist can prevent the ventricular remodeling and improve the ventricular function.Keywords：myocardial infarction;ventricular remodelin;angiotensing converting enzyme inhibitor4|13|0Updated：2024-04-10
- Abstract：This paper presents our experience with radioreqencey ablation （RFA） for idiopathic ventricular tachycardia （VT） arising from right ventricle in 12 patients （pts.）. The age range of patients was 21-50, with a mean of 38.5 years. Ten out of 12 were females, 1 patient had candia failure due to almost incessant VT while the rest had normal left ventricular function. Twelve pts had VT arising from the right ventricle; of those, 9 were from the outflow truct, 2 from the RV apex, and 1 from the RV inflow. In all pts the diagnostic study and therapeutic RFA were combined in a single procedure. Pacemapping and local activition time were used to guide the site of RFA in pts with VT arising from the right ventricle. RFA was successful in 11 of the 12 pts（91 % ）. Number of RF applications were 1 -27, mean 9. 6;fluo- roscopy time were 4-75, mean 26. 9 minutes. RFA for idiopathic RV has a high success rate. This mode of treatment should be considered as a nonpharmacological curative treatment for symptomatic pts.Keywords：radiofrequency ablation;idiopathic VT;right ventricle4|9|0Updated：2024-04-10
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- Abstract：Clinical, electromyographic and pathological features were studied in 18 patients with lipid storage myopathy （group I ） and 18 patients with polymyositis and dermatomyositis （group II）. The results showed a remarkable lower spontaneous activity（SA） incidence （14% ） in group I than that （55% ） in group II; 46% and 34% short-duration motor unit potentials （MUAPs） with polyphasic potentials and 74% and 71% short-duration MUAPs without polyphasic potentials respectively; the percentages of increased polyphasic MUAPs were same in the two groups. The reduced or pathologic interference patterns accounted for 61 % in the group I and 50% in group II. Increased CPK, LDH and HBD were also found in both of them. It is suggested that the lipid storage myopathy may be diagnosed when patients have muscle weakness and myalgia with short-duration and low-amplitude and polyphasic MUAPs without or with occasional spontaneous activities, and increased CPK, LDH and HBD.Keywords：electromyography;lipid storage myopathy;inflammatory myopathy4|18|11Updated：2024-04-10
- Abstract：Objective:To compare the reliability of transvaginal ultrasonography with pelvic arteriography in the assessment of patients with gestational trophoblastic disease. Methods. Transvaginal ultrasonography was performed in 24 patients with gestational trophoblastic tumour. Within one week after ultrasound investigation, pelvic arteriography was carried out in each patient. Of 24 cases, 16 patients hadn’t been treated by chemical reagent, 5 had accepted 2 to 5 courses of chemotherapy, and 3 had achieved complete remission before both investigations performed. Results. In 3 patients with complete remission, 2 had no evidence of abnormal findings either on transvaginal ultrasonography or on pelvic arteriography, 1 showed intramyometrial lesions by both methods. In the remaining 21 patients, all demostrated a abnormal uterine image, and 5 of them accompanied with the finding of parametrium metastatic signs by transvaginal ultrasonography; these abnormal results were confirmed by pelvic arteriographic imaging. However, in two cases without clinical and ultrasonic signs of parametrium metastasis, pelvic arteriography indicated the early metastasis of parametrium ves- sels. Conclusions. Even though it is difficult to predict the early parametrium metastasis in patients with gestational trophoblastic disease by B-ultrasonic investigation, our data would support the introduction of transvaginal ultrasonography in the diagnosis and evaluation of gestational trophoblastic tumour.Keywords：uterus;trophoblastic tumour;transvaginal ultrasonography;pelvic arteriography4|8|2Updated：2024-04-10
- Abstract：Four tibiae removed from 30-40 years males, who died of accidents in less than 12 hours, were os- teomized at medium part. Then these tibiae were fixed by an unilateral hooked-sulcated external fixator （UHSEF）, and the bone-fixator system was used as a model of external fixation of tibial fracture. The axial compression, distraction, torsion, antero-posterior and lateral bending rigidly and the strain of the pins were determined in this system. Based on the results, we found that compared with the configuration of four paralled pins, the rigidity of the fan-like configuraton didn’t decrease significantly if the angle between lateral and medium pins was less than 45’. But the reverse was true when the frame separation increased from 5 to 8 cm. What’ more, the pin strain decreased if the rigidity of the system was improved. These data provided a theoretical basis of biomechanics for the improvement of UHSEF.Keywords：tibia;external fixator;biomechanics)4|5|1Updated：2024-04-10
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- Abstract：Objective. To investigate clinically useful markers for determining the seventy of hemorrhagic shock and adequacy of resuscitation Methods. Prospective study was undertaken in 12 dogs, using an established model for hemorrhagic shock. The anesthetized dogs were bled to a mean arterial pressure of 40 mmHg which was maintained for 3 hours. Then each animal was resuscitated with heperinized whole blood followed by intravenous infusion of dobutamine at a rate of 5 ug. kg-1. min-1 for 10 minutes. Arterial and mixed venous blood gases, arterial lactate concentrations and hemodynamic Parameters were measured throughout the study. Results. A difference in the PCO2 and pH values between arterial and mixed venous blood was observed. Arterial-venous PCO2 and pH difference increased significantly after sustained shock. The arteriovenous carbon dioxide and pH gradients recovered more rapidly than arterial lactate levels after successful resuscitation with blood and dobutamine. Conclusion. Arterial blood gases fail to reflect the acid-base status of tissues during hemorrhagic shock. The differences in PCO2 and pH values between arterial and mixed venous blood could be used as clinical in- dicators for assessing the seventy of shock and efficacy of resuscitation.Keywords：carbon dioxide;hemorrhage shock;blood gas analysis4|14|3Updated：2024-04-10
- Abstract：Objective. To investigate the biomechanical aspects of etiology,pathology, clinical manifestation, diagnosis and surgical treatment of the lumbar spinal stenosis. Methods’ A series of biomechanical methods, such as three-dimensional finite element models. three-dimensional kinematic measurement, cadeveric evaluation, and imaging assessment was applied to correlate lumbar biomechanics and lumbar spinal stenosis. Surgery of lumbar spinal stenosis has been improved. Results. The stresses significantly concentrate on the posterolateral part of the annulus fibrosus of disc, the posterior surface of vertebral body, the pedicle, the interarticularis and the facet joints. This trend is intensified by disc degeneration and lumbar backward extension. Posterior element resection has a definite effect upon the biomechanical behavior of lumbar vertebrae. The improved operations proved satis- factory. Conclusion. Stress concentration in the lumbar vertebrae is of importance to the etiology of degenerative lumbar spinal stenosis, and disc degeneration is the initial key of this process. Then these will be aggravated by backward extension. Functional radiography and myelography are of assistance to the diagnosis o f the lumbar spinal stenosis. For the surgical treatment of the lumbar spinal stenosis, destruction of the posterior element should be avoid as far as possible based upon the thorough decompression. Maintaining the lumbar spine in flexion by fusion after decompression has been proved a useful method. When developmental spinal stenosis is combined with disc herniation, discectomy through laminotomy is recommend for decompression.Keywords：lumbar vertebrae;spinal canal stenosis;biomechanics4|18|5Updated：2024-04-10
- Abstract：From 1970 to 1997, 67 patients with pulmonary hamartoma were operated on in our hospital. There were 38 men and 29 women with a M/F ratio of 1. 3: 1. The mean age was 47 years （range 21 to 82 years）. The peak incidence was 40 to 60 years. 39% Patients had pulmonary symptoms: hemoptysis, cough, phlegm and chest pain. All were solitary. 68. 7% tumors were located in right lung and 64. 2% in upper or middle lobe. 80. 6% hamartomas were less than 3 cm in transverse diameter. On chest films, the opacity was homogeneous in 79.1% cases, heterogeneous in 20.9% and calcifications in 9.0%. The vast majority of shadows were heterogeneous on CT films. Operation is the best treatment for hamartomas. Postoperative mortality was 1. 5%. There was none recurrences and canceration during the follow-up （mean 14 years）.Keywords：pulmonary hamartoma;surgical treatment4|5|2Updated：2024-04-10
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