1996年 · 第109卷第09期

OBJECTIVE This paper is the summary of "National Symposium on the Value of Immunodiagnostic Assays in Schistosomiasis by Treatment Effects Assessment" which was directed by the Expert Advisory Committee for Schistosomiasis of the Ministry of Public Health. This symposium was held to evaluate the diagnostic effects of the new system of detection in the sensitivity and specificity by treatment assessment. MATERIALS AND METHODS Twelve laboratories with 14 assay systems participated in this collaborative study, in which, 450 sera were detected by double blind trial using a classical antibody detection with ELISA as a control. RESULTS The results showed that 6 test systems were superior or close to the classical antibody detection, especially in evaluating the value of treatment effects. CONCLUSIONS It is unanimously recognized that much progress has been made in the research of immunodiagnosis of schistosomiasis in China, but many problems remain to be solved and worth further studying.

OBJECTIVE To investigate the relationships among Trichinella spiralis isolates obtained from different hosts and geographical regions in China. MATERIALS AND METHODS Six isolates of Trichinella spiralis obtained from Changchun, Tianjin, Xi'an, Henan and Yunnan were detected. All the isolates were collected from pigs or dogs. Restriction fragment length polymorphism (RFLP), isoenzyme electrophoresis and soluble protein analysis were used. RESULTS Distinctive banding patterns in restriction maps were seen between Changchun and other isolates studied. A cloned specific repetitive DNA sequence (1.12 kb) from Changchun isolate was then selected to prepare probe for Southern blotting of DNA fragments. The hybridizing banding patterns among the isolates were different and only the Changchun isolate showed the 1.12 kb band. The Changchun isolate was also distinguishable from the other isolates in isoenzyme patterns of GP1, G6PD, HK, 6PGDH and AK, as well as in isoelectric focusing electrophoresis where the Changchun isolate presented a specific band at 4.1 P1. CONCLUSIONS There are at least two different biological types of Trichinella spiralis in China and the differences between them may be attributed to different geographical origins and/or different hosts.

OBJECTIVE To investigate the role of Leptotrombidium (L.) scutellare in the transmission of hemorrhagic fever with renal syndrome (HFRS) and tsutsugamushi disease of autumn-type. MATERIALS AND METHODS Four criteria were used to ascertain this mite as transmitting vector of disease: (1) epidemiological evidence; (2) natural infection of pathogen; (3) ability to transmit pathogen via biting; (4) ability to transfer pathogen via transovarian route. RESULTS The results indicated that L. scutellare was the dominant species of chigger mite on rats. Its seasonal distribution was correlated with the incidence of these two diseases. This mite could be naturally infected by HFRS virus (HFRSV) andRickettsia tsutsugamushi (Rt) and the mite could transmit HFRSV and Rt to vertebrates by biting and to its offspring via transovarian transmission. CONCLUSIONS These results have proved that L. scutellare can be a transmitting vector of HFRS and tsutsugamushi disease of autumn-type.

OBJECTIVE To establish an experimental animal model of rat carrying human hepatitis B virus in the hepatocytes using a simple and reproducible method. MATERIALS AND METHODS Human serum rich in hepatitis B virus was injected into portal veins and caudalis veins of young male Wistar rats. One and two months after the injection, liver biopsies were done. In situ hybridization and immunohistochemical study of liver specimens were carried out. Sera were also examined for HBV DNA by polymerase chain reaction. RESULTS All of seven rats in this experiment were HBV DNA and HBV surface antigen (HBsAg) positive in their hepatocytes. Most HBV positive hepatocytes were distributed around the central vein and scattered in the liver lobules, and HBV DNA and HBsAg were located in cytoplasm. HBsAg exists mainly as the forms of diffuses and inclusion body. No hepatocytic damage or inflammation was observed. Neither viremia nor antigenemia was detected. CONCLUSIONS Our studies showed for the first time that natural human HBV can enter Wistar rat liver cells through intravenous injection efficiently and express for a long period. This animal model can be used in the studies of HBV molecular biology, therapeutic regimens and prophylaxis against HBV. A possible mechanism of HBV entering rat hepatocytes is also proposed.

OBJECTIVE To study red blood cell (RBC) membrane band 3 protein structure and anion transport function in cor pulmonale patients with respiratory failure. PATIENTS AND METHODS Blood samples were obtained from 80 cases of cor pulmonale and 37 normal subjects (control group). The patients were divided into type Ⅰ respiratory failure (Group Ⅰ, n=40) and type Ⅱ respiratory failure (Group Ⅱ, n=40). The anion permeability of the erythrocyte membrane (Pcl), PO2 and PCO2 in 12 of the patients with type Ⅱ respiratory failure were observed in acute stage (AS), chronic stage (CS) and recovery stage (RS). Membrane protein was analyzed by polyacrylamide electrophoresis in SDS. 55-KDa membrane domain was fractionated on 10% NaDodSO4 polyacrylamide gel column and purified further with a sephadax G-25 column. The composition of amino acids was analyzed on a Beckman 6300 Gold system amino acid analyzer. The Pcl was determined by the hypoisotonic hemolysis method. RESULTS The relative content of band 3 protein erythrocytic membrane, anion permeability coefficient of the erythrocyte membrane and plasma chloride in the patients with cor pulmonale with type Ⅱ respiratory failure were significantly lower than those in the patients with type Ⅰ respiratory failure and the control. The number of residues in the anion transport domain of the trypsin fragment of 55,000 daltons of band 3 protein showed no significant difference among the three groups. CONCLUSIONS The structure of anion transport sites remains intact and so the reduction of the anion transport function of band 3 protein in patients with cor pulmonale with type Ⅱ respiratory failure may be due to the decrease of the relative content of band 3 protein, the decrease of extraerythrocytic chloride and hypoxia.

OBJECTIVE To investigate the relationship between left ventricular diastolic dysfunction and episodes of angina decubitus. METHODS The study population consisted of three groups, groups Ⅰ (20 controls) had no cardiovascular diseases. Group Ⅱ (20 patients) had coronary artery disease (CAD) without angina decubitus. Group Ⅲ (24 cases with ejection fraction (EF)>45%) were selected from 26 patients with angina decubitus. RESULTS Left ventriculography (LVG) showed that left ventricular (LV) first 1/3 filling fraction (1/3FF) was significantly reduced in groups Ⅲ as compared with groups Ⅱ and Ⅰ (P<0.01). Left ventricular end-diastolic pressure (LVEDP) significantly increased in patients with angina decubitus after LVG as compared with that before LVG (P<0.01). However, there were no statistically differences in LVEDP, before and after LVG in both groups Ⅱ and Ⅰ. CONCLUSIONS Patients with angina decubitus have abnormalities of LV diastolic filling and decrease in LV compliance.

OBJECTIVE To evaluate the effects of myocardial viability assessment with positron emission tomography on cardiac revascularization decision-making and consequential outcomes of patients with multivessel coronary artery disease. METHODS Thirty-three patients with multivessel coronary disease and heart failure were studied in this series, using 13NH for myocardial perfusion and F-18-deoxy-glucose for myocardial metabolism. Viable myocardium (mis-matched perfusion-metabolism) was visually and quantitatively analyzed in anterior, apical, septal, inferior, and lateral segments of the left ventricle. Left ventricular ejection fraction (LVEF) was also measured with first-pass radionuclide angiocardiography. RESULTS Based on the assessment of myocardial viability, 19 patients (group A) with sufficient viable myocardium underwent revascularization (coronary bypass graft and/or angioplasty), and 14 patients (group B) without sufficient viable myocardium received conservative medical treatment. During an average of 17-month follow-up, there were 2 (10.5%) deaths in group A and 2 in group B (14.3%) deaths (P>0.5). Patients with revascularization showed significantly improved average LVEFs post-revascularization, without revascularization procedure-related mortality; patients with medical treatment had an initial average LVEF of 25% and class Ⅱ-Ⅲ (NYHA) average cardiac function with a survival rate of 86% in average, which was better than that reported in literature. CONCLUSIONS Positron emission tomography is useful in myocardial viability assessment for cardiac revascularization decision-making through precisely selecting suitable patients for revascularization and avoiding operations on those who will not benefit, which results in promising effects on outcomes of patients with multivessel coronary disease and severe left ventricular dysfunction.

OBJECTIVE To study the relation among enzymic ultrastructural localizations, cell organelles and functions of Trichomonas vaginalis (T. vaginalis) as well as its pathogenic mechanism. MATERIAL AND METHODS The specimens were Trichomonas vaginalis cultured purely for several generations. After prefixation, several electron microscopic cytochemical reactions for marker enzymes of lysosome, Golgi body, mitochondrion and microbody as well as Ur-Pb-Cu impregnation were undertaken. Then the specimens were post-fixed and embedded, and the unstained ultrathin sections were observed under a transmission electron microscope. RESULTS The activities of acid phosphatase and cytidine monophosphatase appeared in the primary and secondary lysosomes of the parasite, and the reaction product of peroxidase was found in the secondary lysosomes. It was found that lysosomes could release hydrolytic enzymes out of the cell. The reaction products of thiamine pyrophosphatase and nicotinamide adenine dinucleotide phosphatase were located within the mature-surface and intermediate saccules of Golgi body respectively. The reactions for succinate dehydrogenase, cytochrome oxidase and catalase were negative. The hydrogenosomes, endoplasmic reticulum and Golgi bodies of the parasite were densely stained by Ur-Pb-Cu impregnation method. CONCLUSIONS T. vaginalis has lysosomal system which can release hydrolases out of the parasite, causing damage to the vaginal and urethral epithelial cells. This may be an important pathogenic mechanism of vaginitis and urethritis caused by T. vaginalis. This protozoon has well-developed Golgi bodies and rich endoplasmic reticulum. It lacks mitochondrion and microbody, but has abundant hydrogenosomes which are energy producing organelles of anaerobic metabolism and resemble microbody in morphology and mitochondrion in some functions.

OBJECTIVE To design convenient lateronasal and infrafrontal approaches or lateronasal subvolution approach to radically resect skull base tumors involving cranial cavity. METHODS From 1987 through 1994, 22 patients with malignant tumors, 6 with benign tumors, one with a giant sphenoid sinus cyst and one with intranasal meningoencephalocele underwent the operation. Twenty-three cases had anterocranial fossa involved; 4, midcranial fossa; 2, anteromedial cranial fossa; and 1 case, posteromedial cranial fossa. Among the patients with malignant tumors, 11 underwent expansive maxillectomy and 10 had orbital contents resected. The intracranial approaches through lateronasal and infrafront (21 cases), nasal columella lateral subvolution (3 cases) and other approaches were used. RESULTS The reconstruction of bony skull base defect in excess of 3.00 cm×3.00 cm with total front musculocutaneous flap (8 cases), galeal and pericranial flap (5 cases) or other tissues (3 cases) has effectively prevented meningoencephalocele. Twelve cases had the dura resected in a range of 2.00 cm×2.00 cm to 7.00 cm×6.00 cm. Reconstruction of the dura defect with autofascia lata in 9 cases and other tissues in 3 cases effectively prevented the cerebrospinal fluid leak. Eight of 22 (36.4%) patients with malignant tumors have been alive and free of disease for 3-7 years after the operation. Six patients with benign tumors, one patient with giant sphenoid sinus cyst and one with meningoencephalocele were cured with this reconstructing method. CONCLUSIONS Frontal musculocutaneous and pericranial flaps have advantages over free bone because of easy surviving and easy operating without occurrence of osteonecrosis and exclusive reaction.

OBJECTIVE To reveal the sequence of events of osteoclastic resorption taking place in the cortical bone of the femoral neck in aged women. MATERIAL AND METHODS The cross sections of cortical bones of the femoral neck from 7 aged women who underwent endoprosthetic replacement for intracapsular hip fracture, were processed and subjected to scanning electron microscopic observation. RESULTS The cortical bone sections revealed enlargement of the Haversian canals. On the inner linings of the enlarged canals many oval resorption lacunae could be found, reflecting osteoclastic resorption of the Haversian systems. The osteoclastic resorption with subsequent enlargement of the Haversian canals into round or oval cavities took place first over the inner portions of the cortical sections, thereby rendering these areas porotic (cancellization). These processes of the Haversian systems and canals then gradually emerged over the central and eventually over the outer areas of the cortical bone, and the entire cortical bone became porotic. Meanwhile, the inner porotic portion of the cortex turned into trabeculae (trabecularization) and became gradually resorbed, resulting in thinning of the medial cortex. CONCLUSIONS Cortical cancellization, trabecularization and thinning compromised the material strength of the femoral neck so that fracture would ensue even with trivial injury.