[Comparative study of gap balancing and measured resection technique in patients receiving staged bilateral total knee arthroplasty].

Objective: To compare the clinical outcomes of staged total knee arthroplasty (TKA) performed on both knees in the same patient using gap balancing (GB) and measured resection (MR) techniques, respectively. Methods: The clinical data of 57 patients undergoing bilateral staged TKA at the Xi'an Jiaotong University Affiliated Honghui Hospital from July 2018 to January 2020 were analyzed. Using the random number table, MR or GB technique was selected when patients underwent primary TKA, and contralateral procedure was done with another technique. The procedures were performed by one chief surgeon, and the same prosthesis was chosen for all the procedures. The two osteotomy techniques for TKA were compared in terms of surgical status, radiographic data, functional recovery and satisfaction rate. Results: Total of 57 patients, including 16 males and 41 females, were included in the study with a mean age of (68.5±4.6) years (59-79 years) at primary TKA. All patients were followed up for (29.6±4.5) months (22-39 months). The interval between the two procedures was (4.7±3.0) months (0.5-12.0 months). Postoperative drainage was less in the GB side when compared with that in the MR side [(93.6±22.2) ml vs (109.9±36.9) ml, P=0.003]. At the 1-month postoperative follow-up, the visual analogue scale (VAS) of pain was lower on the GB side (3.0±0.8) than on the MR side (3.5±1.2), the range of motion (ROM) was higher on the GB side (105.7°±8.2° vs 100.2°±7.5°), the Knee Society Score (KSS) was higher on the GB side (78.5±5.4 vs 74.2±6.3), and the Western Ontario and McMaster University (WOMAC) score was lower on the GB side (35.4±5.5 vs 38.0±6.3), there were significant differences in the up-mentioned indexes between the two groups (all P<0.05). However, the repeated-measures analysis of variance indicated that there was no significant difference in VAS score, ROM, KSS score and WOMAC score between the two techniques (all P>0.05). The satisfactory rate of GB technique was 84.2%(48/57), ant it was 86.0%(49/57) with MR technique (P=0.446). There was also no significant difference between the two techniques in terms of complications (P=0.754). Conclusion: Both the GB and MR technique result in good knee function with similar clinical outcomes in patients receiving TKA in both knees for osteoarthritis without significant deformity.

Action of the insecticide cyfluthrin on Ca2+ signal transduction and cytotoxicity in human osteosarcoma cells.

Cyfluthrin is a pyrethroid insecticide and common household pesticide. The effect of cyfluthrin on Ca2+-related physiology in human osteosarcoma is unclear. This study investigated the effect of cyfluthrin on cytosolic-free Ca2+ concentrations ([Ca2+]i) and viability in MG63 human osteosarcoma cells. Cyfluthrin concentration-dependently induced [Ca2+]i rises. Cyfluthrin-induced Ca2+ entry was confirmed by the Mn2+-induced quench of fura-2 fluorescence. Cyfluthrin at concentrations of 10-100 µM induced [Ca2+]i rises. Ca2+ removal reduced the signal by approximately 50%. Cyfluthrin (100 µM) induced Mn2+ influx suggesting Ca2+ entry. Cyfluthrin-induced Ca2+ entry was inhibited 50% by protein kinase C (PKC) activator (phorbol 12-myristate 13-acetate) and inhibitor (GF109203X) and also by three inhibitors of store-operated Ca2+ channels: nifedipine, econazole, and SKF96365. In Ca2+-free medium, treatment with the endoplasmic reticulum Ca2+ pump inhibitor thapsigargin (TG) completely inhibited cyfluthrin-evoked [Ca2+]i rises. Conversely, treatment with cyfluthrin abolished TG-evoked [Ca2+]i rises. Inhibition of phospholipase C (PLC) with 1-[6-[((17ß)-3-methoxyestra-1,3,5[10]-trien-17-yl)amino]hexyl]-1H-pyrrole-2,5-dion abolished cyfluthrin-induced [Ca2+]i rises. Cyfluthrin at 25-65 µM decreased cell viability, which was not reversed by pretreatment with the Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester. Together, in MG63 cells, cyfluthrin induced [Ca2+]i rises by evoking PLC-dependent Ca2+ release from the endoplasmic reticulum and Ca2+ entry via PKC-sensitive store-operated Ca2+ entry. Cyfluthrin also caused Ca2+-independent cell death.

Ca2+ movement and cytotoxicity induced by the pyrethroid pesticide bifenthrin in human prostate cancer cells.

Bifenthrin, a commonly used pyrethroid pesticide, evokes various toxicological effects in different models. However, the effect of bifenthrin on cytosolic-free Ca2+ level ([Ca2+]i) and cytotoxicity in human prostate cancer cells is unclear. This study examined whether bifenthrin altered Ca2+ homeostasis and cell viability in PC3 human prostate cancer cells. [Ca2+]i in suspended cells were measured using the fluorescent Ca2+-sensitive dye fura-2. Cell viability was examined by 4-[3-[4-lodophenyl]-2-4(4-nitrophenyl)-2H-5-tetrazolio-1,3-benzene disulfonate] water soluble tetrazolium-1 assay. Bifenthrin (100-400 µM) concentration-dependently induced [Ca2+]i rises. Ca2+ removal reduced the signal by approximately 30%. In Ca2+-free medium, treatment with the endoplasmic reticulum Ca2+ pump inhibitor 2,5-di-tert-butylhydroquinone (BHQ) abolished bifenthrin-evoked [Ca2+]i rises. Conversely, treatment with bifenthrin abolished BHQ-evoked [Ca2+]i rises. Inhibition of phospholipase C (PLC) with U73122 significantly inhibited bifenthrin-induced [Ca2+]i rises. Mn2+ has been shown to enter cells through similar mechanisms as Ca2+ but quenches fura-2 fluorescence at all excitation wavelengths. Bifenthrin (400 µM)-induced Mn2+ influx implicates that Ca2+ entry occurred. Bifenthrin-induced Ca2+ entry was inhibited by 30% by protein kinase C (PKC) activator (phorbol 12-myristate 13 acetate) and inhibitor (GF109203X) and three inhibitors of store-operated Ca2+ channels: nifedipine, econazole, and SKF96365. Bifenthrin at 175-275 µM decreased cell viability, which was not reversed by pretreatment with the Ca2+ chelator 1,2-bis(2-aminophenoxy) ethane-N,N,N',N'-tetra acetic acid-acetoxymethyl ester. Together, in PC3 cells, bifenthrin-induced [Ca2+]i rises by evoking PLC-dependent Ca2+ release from the endoplasmic reticulum and Ca2+ entry via PKC-sensitive store-operated Ca2+ entry. Bifenthrin also caused Ca2+-independent cell death.

Phorbol ester-potentiated liposomal transfection to monocytic PLB-985 cells.

In order to improve transient gene transfer into PLB-985 cells, we treated cells with 12-tetradecanoylphorbol 13-acetate (TPA) 4 h before transfection, and increased by 540-fold the reporter activity of the firefly luciferase gene transfected by TFL-01, a cationic liposome. Dioctanolyglycerol added before TPA addition inhibited the TPA-dependent increase in activity, suggesting it to be a TPA competitor for PKC binding. H7, staurosporine, GO 6976, and H8, but not GF 109203X and forskolin, inhibited the TPA-dependent increase in reporter activity when added 8 h after TFL-01/gene addition. Forskolin and GF 109203X also inhibited the increase when added before TPA. Therefore, for the potentiation of transfection by the TPA/TFL-01 method, conventional PKC activity with significant but low protein kinase A (PKA) activity are first required, and then a novel PKC activity with significant PKA activity. TPA enhanced the uptake of FITC-labeled phosphorothioated oligonucleotides and their prolonged maintenance by cells, suggesting increased TFL-01-assisted plasmid uptake and its stabilization in TPA-treated PLB-985 cells. This method was used successfully for the sensitive analysis of the promoter function of the gp91(phox) gene, implying the method to be generally useful for promoter analyses of various genes expressed in differentiated human monocytic cells.

A multicenter, randomized, controlled trial of interferon alfacon-1 compared with alpha-2a-interferon in Chinese patients with chronic hepatitis C virus infection.

BACKGROUND: Alpha-interferons are the accepted therapy for patients infected with chronic hepatitis C virus (HCV) in China. However, consensus interferon (CIFN) for HCV treatment is effective in patients with chronic hepatitis C from Western countries. METHODS: This randomized, controlled trial was conducted to determine the safety and efficacy of CIFN at two doses, and to compare it with alpha-2a-interferon (IFN-alpha-2a) in Chinese patients with chronic HCV. Interferon-naive patients with chronic HCV infection (n = 187) were randomly chosen to receive 15 microg CIFN or 9 microg or 3 MU IFN-alpha-2a subcutaneously, three times a week for 24 weeks, followed by a 24 week observation period. Efficacy was evaluated by the normalization of serum alanine aminotransferase (ALT) and the non-detectability disappearance of serum HCV-RNA by using reverse-transcription-polymerase chain reaction. The safety of CIFN was evaluated by recording the type and severity of adverse effects. RESULTS: The combined ALT and HCV-RNA end-of-treatment and sustained responses were observed to be greater for treatment with 15 microg CIFN (59.0% and 55.7%, respectively) compared to IFN alpha-2a (36.1% and 39.3%, respectively; P = 0.01 for the end-of-treatment, P = 0.07 for the sustained response). The combined ALT and HCV-RNA end-of-treatment and sustained responses for treatment with 9 microg CIFN (both 49.2%) were higher than those for IFN-alpha-2a (not statistically significant). Data were analyzed by using a logistic-multiple-variate regression model, which indicated that the higher IFN dose (15 microg or 9 microg CIFN vs 3 MU IFN-alpha-2a; P < 0.01) appeared to be associated with a better sustained response. The type, frequency and severity of adverse effects were comparable across treatment groups. CONCLUSIONS: Consensus interferon appears to be safe and effective at concentrations of 9 and 15 microg, but 15 microg CIFN may be more effective than 3 MU IFN-alpha-2a, without increased toxicity.

Molecular cloning and characterization of major histocompatibility complex class I cDNAs from woodchuck (Marmota monax).

The full-length cDNAs of woodchuck major histocompatibility complex (MHC) class I (MhcMamo-I or Mamo-I) genes were cloned by using cellular mRNA isolated from the peripheral blood mononuclear cells and liver tissues of woodchucks. DNA sequence analysis of Mamo-I cDNAs revealed that the coding regions of Mamo-I genes were about 1,080 bp long, encoding 359 amino acid residues. The deduced amino acid sequences of Mamo-I showed structural features like leader, alpha1, alpha2, alpha3, transmembrane and cytoplasmic domains, similar to their homologues in human and other mammals. Analysis of five full-length clones from unrelated woodchucks indicated a polymorphism within the alpha1 and alpha2 domains of Mamo-I heavy chain and a high conservation within the alpha3 and the transmembrane/cytoplasmic domains. Amino acid residues of the alpha2 and alpha3 domains that are supposed to be involved in the binding of MHC class I to CD8 molecule, were largely conserved in Mamo-I genes. Phylogenetic comparison of MHC class I genes of woodchuck and other mammals indicated a close evolutionary relationship between woodchuck and squirrel MHC class I. We tentatively named this region the locus A of Mamo-I genes (Mamo-A). Sequence analysis of 101 clones of alpha1 and alpha2 regions derived from 14 woodchucks revealed that at least 14 different alleles within Mamo-A exist. Among these 14 alleles identified so far, Mamo-A*01 and Mamo-A*09 were of the highest frequency of about 21.5% and 14.5%, respectively. Our results indicate that Mamo-I genes are of a similar molecular structure to those of human and other mammals.

Eosinophil-specific regulation of gp91(phox) gene expression by transcription factors GATA-1 and GATA-2.

The glycoprotein gp91(phox) is an essential component of the phagocyte NADPH oxidase and is expressed in eosinophils, neutrophils, monocytes, and B-lymphocytes. We previously suggested an eosinophil-specific mechanism of gp91(phox) gene expression. To elucidate the mechanism, we performed functional assays on deletion mutants of the gp91(phox) promoter in various types of gp91(phox)-expressing cells. A 10-base pair (bp) region from bp -105 to -96 of the promoter activated transcription of the gene in eosinophilic cells, but not in neutrophilic, monocytic, or B-lymphocytic cells. A 2-bp mutation introduced into the GATA site spanning bp -101 to -96 (-98GATA site) of the fragment abolished its activity. Gel shift assays using a GATA competitor and specific antibodies demonstrated that both GATA-1 and GATA-2 specifically bound to the -98GATA site with similar affinities. Individual transfection of GATA-1 and GATA-2 into Jurkat cells, which have neither endogenous GATA-1 nor GATA-2, activated the -105/+12 construct in a -98GATA site-dependent manner. Combined transfection of GATA-1 and GATA-2 activated the promoter less than transfection of GATA-1 alone. These results suggest that GATA-1 is an activator and that GATA-2 is a relative competitive inhibitor of GATA-1 in the expression of the gp91(phox) gene in human eosinophils.

Parathyroid hormone and parathyroid hormone related protein assays in the investigation of hypercalcemic patients in hospital in a Chinese population.

There are many pathological causes and potential mechanisms for hypercalcemia. We measured intact parathyroid hormone (PTH) and parathyroid hormone related protein (PTHrP) in the hypercalcemic in-patients and attempted to evaluate the roles of PTH and PTHrP in hypercalcemia due to malignancy. We performed a prospective study of 178 patients with corrected serum calcium concentrations greater than 2.74 mmol/l in a hospital over a 3-year period. We measured calcium and albumin using a Hitachi 747 autoanalyzer, and we measured PTH and PTHrP by two-site immunoradiometric assays (IRMA). Hypercalcemia was attributed to malignancy alone in 93 patients (52.3%), primary hyperparathyroidism (HPT) alone in 28 patients (15.7%), uremia with hemodialysis in 23 patients (12.9%), unknown in 16 patients (9%), primary HPT coexisting with malignancy in 7 patients (3.9%) and other rare causes (6.2%). Plasma PTHrP levels were elevated in 71/93 (76.3%) patients with hypercalcemia due to malignancy, but the elevated PTHrP percentage differed for each kind of tumor. PTHrP levels were elevated in 100% of patients with squamous carcinomas (CA) in the lung, esophagus, skin, cholangiocarcinoma of liver, and breast CA. The positive bony metastatic rate was 44.1% (41/93). There was no correlation between high PTHrP and bony metastasis. There was a good correlation between the corrected serum calcium and PTHrP levels (r = 0.476, p < 0.001), but no correlation between survival time and serum calcium level or PTHrP level. There was no significant difference in life expectancy after cancer diagnosis between the high PTHrP group and normal PTHrP group, and there was no significant difference in life expectancy after the first occurrence of hypercalcemia between the two groups. Measurement of both PTH and PTHrP levels led to a change in the initial diagnosis in 7 patients. In routine practice, measurement of serum PTH alone is not enough. This study suggests that the appropriate combination of PTH and PTHrP assays results in a more accurate diagnosis of the hypercalcemic causes. In addition, especially high PTHrP levels should be screened for malignancy. However, the prognosis in cancer patients after hypercalcemia with high PTHrP group, as compared to those with the normal PTHrP group is not significantly different.

Short- and long-term effect of interferon therapy for chronic hepatitis C.

AIM: To study the short and long-term effect of interferon therapy for chronic hepatitis C. METHODS: Sixty-eight patients with chronic hepatitis C were treated with interferon (3 × 10(6) IU, im/2 d, for a course of three months) with 1 to 5 courses of treatment and followed for 1.5 to 3 years after the therapy. RESULTS: According to antiviral effect of interferon, 76.5% (52/68) of the cases had a complete response by the end of the first therapy course, while 20.6% (14/68) and 2.9% (2/68) had a partial response or non-response. Over a half of the patients with a complete response (27/52, 51.9%) relapsed within 6 to 10 mo after the first course. Of the original cohort, nineteen patients received two courses of therapy, while one patient received three and another three received five courses of therapy. The follow-up for these patients was between 1.5 to 3 years, at which time 29 (42.7%) of the patients sustained a complete response, with four of them having HCV RNA positive serum, while the others had either a partial (37/68, 2.9%) or non-response. CONCLUSION: Interferon therapy had a high short-term complete response but a low long-term complete response in the treatment of chronic hepatitis C.

Late-onset idiopathic hypoparathyroidism with thymoma: a case report.

A 62-year-old male was admitted because of numbness and twitching of both hands. Hypocalcemia with positive Trousseau's sign was noted. Chest X-ray and computed tomography (CT) showed an anterior mediastinal mass. Skull X-ray and whole body bone scan could not rule out bony metastasis to the left parietal bone, causing an anterior mediastinal tumor with bony metastasis to be suspected initially. Median sternotomy and extended thymectomy were done, and Stage II thymoma with negative calcitonin staining was noted. However, hypocalcemia persisted after thymectomy and the results of pre-operative and post-operative intact-parathyroid hormone (intact-PTH) were less than the detection limit (<13.3 pg/ml). Tumor markers and gallium tumor scan were all negative. Brain CT disclosed calcification over the bilateral basal ganglia and bilateral dentate nuclei of the cerebellum; the supposed metastatic osteolytic lesions of parietal bone were considered to result from pacchionion arachnoid granulation tissues. The coexistence of late-onset idiopathic hypoparathyroidism and thymoma has not been reported before. Long-term replacement therapy with vitamin D and calcium was necessary for this case.

Does endothelin play a role in the pathogenesis of early diabetic nephropathy?

Endothelin-1 (ET-1) causes dramatic vasoconstriction and reduction of renal blood flow, with a decreased glomerular filtration rate (GFR). Early diabetic nephropathy is characterized by elevation of GFR and the formation of intrarenal microaneurysms. However, the mechanisms are unclear. To elucidate the pathophysiologic significance of urinary ET-1 in early diabetic nephropathy, the 24-h urinary excretion of ET-1 in 12 normal subjects and 20 patients with newly diagnosed type 2 diabetes mellitus were determined by a highly sensitive radioimmunoassay. The 24-h urinary ET-1 excretion in patients with diabetes mellitus (14.2 +/- 3.1 pmol, mean +/- SEM) was significantly lower (p < 0.05) than that of normal subjects (25.0 +/- 3.7 pmol). This decrease in urinary excretion of ET-1 in patients with recent-onset diabetes mellitus suggests a possible role of ET-1 in the pathogenesis of early diabetic nephropathy.

[Study of HCV infection and viremia in patients with posttransfusion hepatitis in China]. / HCV-Infektion und Virämie bei Patienten mit Posttransfusionshepatitis in China.

One hundred and sixty-nine patients with posttransfusion hepatitis (PTH) were investigated for etiology with serological and PCR methods. Our result showed that HCV was the major causative agent of PTH in this study. A part of patients (24/169) were also HBV markers positive. Three patients were negative for all detected viral markers, looking forwards to progressive study. Anti-HCV was detectable from 7 days to one year after onsetting of clinical symptoms, average time 54.62 days. HCV RNA could be detected in early time of HCV infection ( 6 to 20 days later), average time 8.72 days. A follow-up study of 84 patients showed that all patients remained anti-HCV positive during the observation for 1.5 -- 3 years, but their HCV viremia had three forms: transient, persistent or intermittent. The interaction between HCV and HBV by their superinfection was unknown, awaiting further study.

Infectivity and risk factors of hepatitis C virus transmission through sexual contact.

HCV infection among heterosexuals with multiple partners and family members of patients with hepatitis C, and HCV RNA in the body fluid of these patients were investigated. The results showed that the HCV infection in heterosexuals with multiple partners, which was related to sexual activity, was much higher than that of healthy pregnant women. The HCV RNA in the saliva, semen or vaginal discharge of patients with hepatitis C was at detectable level. Among the patient's relatives, none of the children but 2 spouses were found to be infected with HCV. We concluded that sexual contact might play some role in HCV transmission.

[A preliminary study of HCV infections with hemophilia and their family members]. / HCV-Infektion bei Hämophilie-Kranken und deren Familienangehörigen.

28 cases of hemophilia were examined for HCV infection status by using the Kehua anti-HCV ELISA kit of second generation. It was found that the infection rate was 78.5% and the infection rate was even higher with patients who had received transfusions or preparations of coagulatory factors. 10 families of 15 patients were also investigated. It was found that of 15 hemophilia patients, 12 showed positive anti-HCV, while none of their 53 family members exhibited any positive anti-HCV. In 8 children of 9 couples no positive anti-HCV was found. Our results revealed that the hemophilia patient may get infected with HCV by receiving multiple transfusions or preparation of coagulatory factors. The risk of getting infected with HCV via daily-life contact including sexual contact is extremely low.

Relationship between the characteristics of immunopathological expression of hepatitis C virus antigen and hepatocytic injury.

Biopsied liver tissues from 352 cases were tested for hepatitis C virus (HCVAg) with improved PAP immunohistologic chemical method. Furthermore, corresponding seroantibody to hepatitis C virus was also tested. The total HCVAg positive rate was 9.1%. The HCVAg positive rate in chronic persistent hepatitis (CPH) was 5%. The HCVAg positive rate in chronic active hepatitis (CAH) was 11.2%. The HCVAg positive rate raised gradually along with the severity of hepatocytic injury. HCVAg may be seen in necrotic liver cells exfoliating into the liver sinus, indicating a close relationship between HCVAg and hepatocytic injury. Expression of HCVAg was mostly of the nucleus type in CPH cases and was mostly of the plasma type in CAH cases. The periphery of nucleus type-expressed positive cells generally had no marked inflammatory cell infiltration. The periphery of plasma type-expressed positive cells had a certain amount of inflammatory cell infiltration. Along with the severity of hepatocytic injury, HCVAg expressed itself in a positive correlation according to the nucleus and plasma types. The HCVAg positive cells were located mostly in the lobular peripheral band and rarely located in the venoperipheral band. It was possible that this had some relation with the lobular microcirculation of blood and blood supply. In this study, there was no obvious correlation between the HCVAg positive rate in hepatic tissues and the anti-HCV positive rate in sera. Neither the patients with HCVAg positive liver tissues nor the patients with seropositive anti-HCV had any history of blood transfusion and the use of blood products.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies to hepatitis C virus and hepatitis C virus RNA in Chinese blood donors determined by ELISA, recombinant immunoblot assay and polymerase chain reaction.

Antibodies to hepatitis C virus (anti-HCV) were determined in Chinese blood donors from the city of Wuhan by ELISA screening tests and confirmatory recombinant immunoblot assay (RIBA). 281 and 222 sera were sampled under similar conditions in 1989 and 1990, respectively. The first collection of sera was sent to Sweden in lyophilized form, the second directly as fresh, unfrozen sera. A high proportion (22%) of the lyophilized sera were positive in the screening assay but only 6 (2.10%) were positive by RIBA with antibodies against both the C100-3 and 5-1-1 peptides. HCV RNA could be detected by polymerase chain reaction (PCR) analysis in 3 of the 6 sera and in one reacting with C100-3 only. In the second material of fresh sera only 3 were positive in the screening anti-HCV ELISA, but none was RIBA or PCR positive. Thus, the overall prevalence of anti-HCV among the 503 Chinese blood donors as identified by RIBA was 1.2%, and that of HCV RNA by PCR was 0.8%. The confirmed antibody prevalence is higher than that reported in the western literature.

Hepatitis C virus infection: its role in chronic liver diseases.

In order to find out the infectious rate of hepatitis C virus (HCV) among chronic liver diseases, we investigated antibodies against hepatitis C virus and HCVRNA by method of ELISA, RIBA and RT-PCR in 410 patients with chronic liver disease. The prevalence of HCV infection was found to be 4%. Whereas the positive rate of HBsAg and HBV-DNA of these cases was 69% and 58%, respectively. There is no statistical significance between HCV infectious rate of patients with positive and negative HBsAg. The relative low infectious rate of HCV infection among chronic hepatic diseases indicates that HBV infection plays a more important role in causing chronic hepatitis than that of HCV. Thus, special emphasis should be paid to the preventive and therapeutic measures against hepatitis B in China.

Hepatitis B virus DNA detected by PCR in sera and liver tissues of Chinese patients with chronic liver diseases.

To investigate the HBV infection and its replication in Chinese patients with chronic liver disease, polymerase chain reaction (PCR) was employed to detect hepatitis B virus DNA in sera of 410 patients with chronic liver disease and liver samples from 188 patients. The HBV DNA detectability in all serum samples was 58%. Among them 100% HBeAg-positive and 58% anti-HBe cases were HBV DNA detectable respectively. However, HBV DNA was also found in 23% HBsAg-negative/anti-HBc positive chronic cases. Furthermore, 30% anti-HBs positive chronic cases who had neutralizing antibody against HBV infection, continued to contain HBV DNA. Our findings indicate that HBV infection and its replication are dominant cause of chronic liver disease and some HBV variants may escape from the protective antibody to induce chronic liver disease, even anti-HBs antibody circulated.

Establishment and application of SPA-co-operated ELISA for detection of anti-HCV-IgM.

A staphylococcus aureus protein A co-operated ELISA (SPA-ELISA) for the detection of anti-HCV-IgM has been established using HCV antigenic polypeptide, SPA-bearing germs and horseradish peroxidase labelled anti-human IgM. The specificity of SPA-ELISA has been confirmed by some substitution tests, blocking tests and destroying test with 2-mercaptoethanol. The results showed that the rate of anti-HCV-IgG in a group of patients with acute hepatitis and there were significant difference in anti-HCV-IgM was higher than that of anti-HCV-IgM detected rates between patients with acute hepatitis and those with chronic hepatitis (32.26%, P < 0.01). On the other hand, the positive rates of anti-HCV-IgM were 53.66% and 63.41% in transfusion associated hepatitis, 38.10% and 42.86% in sporadic hepatitis, 6.11% and 16.33% in people who have had active social activities, 40.00% and 10.00% in a group of blood donors respectively. Furthermore, taking into account the characteristics of HCV polypeptide used, its easiness of manipulation, and elimination of the interference of anti-HCV-IgG in sera, the new SPA-ELISA is believed to be of practical value in clinical and epidemiological studies of hepatitis C.