Detection and characterization of IL-1 receptor antagonist in tissues from healthy rabbits: IL-1 receptor antagonist is probably involved in health

Interleukin 1 (IL-1) is postulated to function in maintaining homeostasis, however, over-action of this cytokine may lead to disruption of homeostasis due to it's wide spectrum of activities. To understand the endogenous regulation of this cytokine, we examined the existence of IL-1 receptor antagonist (IL-1Ra) in tissues from healthy rabbits. IL-1Ra was constitutively produced in all tissues examined (lung, liver, spleen, thymus, caecum, skin, kidney, heart, and brain), as estimated by ELISA. Immunoprecipitation, RT-PCR and immunohistochemical studies indicated that all tissues produced secreted form of IL-1Ra (sIL-1Ra), whereas thymus, caecum, skin and kidney produced both sIL-1Ra and intracellular of IL-1Ra. All tissue IL-1Ra purified using anti-IL-1Ra IgG affinity chromatography had inhibitory activity on the IL-1-induced thymocyte proliferative response, and the activity was totally abolished by anti-IL-1Ra mAb. No IL-1 activity was detected in any tissues except skin and heart, however, after preincubation of the samples with anti-IL-1Ra, the activity was first visible in the tissues. Under these conditions, IL-1 activity in skin and heart was enhanced to 170% and 280%, respectively. Taken together, we conclude that tissue IL-1Ra is involved in health maintenance by masking co-existing IL-1 activity present in tissues.

Synchronous and metachronous carcinomas of the esophagus and head and neck

We retrospectively analyzed the clinicopathologic findings, treatment and outcome of 22 patients with synchronous or metachronous carcinomas of the esophagus and head and neck. The patients with metachronous cancers in whom esophageal cancer occurred first had either an early-stage esophageal carcinoma or only one positive lymph node. Similarly, five of 10 patients with metachronous cancers in whom head and neck cancer was the first tumor had early-stage esophageal carcinomas. The esophageal lesion was mucosal carcinoma in four patients which was found by endoscopy with the iodine dye method. In the patients with synchronous cancers either one or both carcinomas were advanced, and the prognosis of these patients was poor compared with those of patients with metachronous carcinomas. Accordingly, endoscopic surveillance for early detection of metachronous lesions are encouraged.

Analysis of allogenic lymphocytes in rat thymus following sublethal irradiation

The effects of allogeneic lymphocytes on the rat thymus following sublethal irradiation were investigated using immunofluorescence. The recovery of thymus weight following irradiation was delayed in rats 6 days after receiving lymphocytes compared to controls. Allogeneic cells forming colonies were detected by immunofluorescence in both the cortex and medulla of the host thymus, most frequently on day 15 when an appropriate number (3 x 10(6)) was injected. The allogeneic cells detected in the host thymus, presumably T lymphocytes, appeared to disturb thymic reconstitution following irradiation. However, double-immunofluorescence staining revealed that allogeneic cells did not affect the thymic stromal microenvironment. Allogeneic cells may have subsequently affected thymic tissue via cytokines. It is important to investigate not only the character of allogeneic cells in the host thymus but also the interactions of donor allogeneic cells, host immature lymphocytes and thymic epithelial cells because of the possibility that these allogeneic cells in the host thymus could prevent the rejection of allogeneic transplants.

Appraisal of ten-year survival following esophagectomy for carcinoma of the esophagus with emphasis on quality of life

Characteristics of 10-year survival after esophagectomy for carcinoma were studied retrospectively in 161 patients who underwent curative operation between 1973 and 1984. Of the 161 patients, 44 (27.3%) survived for 10 years after operation (right transthoracic approach with cervical anastomosis in 36 patients and left thoracoabdominal approach with jejunoesophagostomy in 8 patients). Females survived significantly longer than males; 10-year survival was observed in 10 (50%) of 20 females and 34 (24.1%) of 141 males. TNM factors were significantly linked to the 10-year survival for 25 patients (56.8%) whose tumors invaded the adventitia and 20 patients (45.5%) who had lymph node metastases, where the total number of involved nodes was less than eight. A questionnaire mailed 10 years after operation revealed that about one-fifth of the 10-year survivors could not go up one flight of stairs without taking a rest, and that the daily activity significantly deteriorated if the patient's age at the time of surgery was more than 66 years. One-third of the 10-year survivors were not satisfied with the daily quantity of food intake, resulting in no gain of body weight after discharge from the hospital. This complaint was significantly correlated with either weekly reflux or heartburn, resulting in the increasing number of nonmalignancy deaths. Of 13 ten-year survivors who were alive at 10 years but died after that, 11 (84.6%) died of pneumonia or malnutrition. Duodenogastroesophageal reflux may eventually cause nonmalignancy death 10 years after esophagectomy for carcinoma.

Morphological and flow cytofluorometrical analyses of regenerated rat thymus after irradiation

Reconstituted rat thymuses were studied by immunohistochemistry, transmission electron microscopy (TEM) and flow cytofluorometry on days 0, 1, 2, 3, 5, and 7 after whole-body sublethal irradiation (6 Gy). One day after irradiation, numerous apoptotic cells were seen in the cortical thymus; the percentage of the sub-G1 peak representing apoptotic cells was 8.9% in the DNA content histogram of cytofluorometry. On day 3, the thymic structure had been destroyed and no distinction was drawn between the cortex and medulla. In this stage, few thymocytes but many macrophages were present, and the percentage of the sub-G1 peak reached a peak at 13.0%. Bromodeoxyuridine (BrdU) incorporated cells gradually increased after irradiation, and immunohistochemically numerous apoptotic cells were found primarily in the cortex on day 7. These thymocytes showed some levels of electron density of the nucleus as revealed by TEM. The percentage of S phase cells did not change markedly (20-30%) based on one-color DNA content histograms, but the percentage of early S and S phase cells was extremely high on day 7 (70%). These data indicate that a part of DNA synthetic cells may result in apoptosis. The combination of immunohistochemistry, TEM and flow cytofluorometry to analyze DNA content and BrdU incorporation proved a useful tool for investigating the reconstituted thymus.

[A case of advanced esophageal cancer successfully treated by concurrent use of radiotherapy and low-dose CDDP and continuous infusion of 5-FU]

A 75-year-old male patient with advanced esophageal cancer was treated by radiotherapy and chemotherapy. External radiotherapy was performed by the field in field method. A total dose of 60 Gy was used in the small field (7 x 5 cm) (2.4 Gy/f and 25 f/5 wks) and a total dose of 45 Gy in the large field (14 x 6 cm) (1.8 Gy/f, 25 f/5 wks). Concurrent chemotherapy was performed at the 2nd and 5th weeks of the radiation therapy. In this chemotherapy of CDDP plus 5-FU, CDDP (25 mg/day) was given on days 1,3 and 5 of the week and 5-FU (500 mg/day) was given for 5 days by continuous infusion for the same week. By this treatment, a complete response (CR) was obtained, and no serious side effects were observed. After 1 year and 6 months, he is alive with no evidence of recurrence.

Precise analyses of the structure of the thymus for establishing details of the mechanisms underlying thymocyte proliferation and maturation

Details of thymocyte proliferation and maturation are important for understanding the variability of T cell functions. The following aspects need to be clarified in this context: 1) Ascertaining why hematopoietic committed pre-T cells migrating in the blood stream are trapped and proliferate in the subcapsular region of the thymus. Further morphological and functional studies of stromal cells in situ in the thymus should be conducted. The factors responsible for thymocyte proliferation should be also analysed. 2) How phenotypic maturation of thymocytes takes place and how T-cell receptor (TCR) expression is processed and controlled. 3) Subsequently, how does the selection of thymocytes take place? Is negative selection in fact responsible for the unresponsiveness of the body to self antigens? Further morphological analyses of thymic epithelial cells, thymocytes themselves and macrophages need to be conducted, together with immunohistochemical analyses using many monoclonal antibodies directed against these cells and the extracellular matrix, in order to analyse the cellular dynamics and cell-to-cell interactions occurring in thymus tissues in situ. 4) How mature thymocytes migrate to the periphery: Perivascular structures and the cells accumulating in this space should be intensively analysed morphologically and phenotypically. Lymphatic structures related to the thymus tissues also remain to be studied. To understand these questions, several useful experimental systems can also be employed: 1) Phylogenetical analyses, 2) ontogenical analyses, 3) thymus tissues regenerating from radiation or thymotoxic drugs, 4) thymomas, and 5) thymus tissues from transgenic animals. These important problems could be further studied in such experimental models both morphologically and immunohistochemically, since many useful tools are now available for studies of phenotypic and other markers of thymocytes and thymic epithelial cells. Subsequently, further detailed analyses of thymic structures may shed more light on the mechanisms underlying thymocyte proliferation and maturation.

Neonatal lupus erythematosus: analysis of HLA class II alleles in mothers and siblings from seven Japanese families

BACKGROUND

Neonatal lupus erythematosus (NLE) is a syndrome characterized by dermatitis and congenital heart block. The disease is mostly associated with transplacental passage of maternal anti-Ro(SS-A) or anti-La(SS-B) antibodies. Maternal HLA-DR3 and DQ2 alleles are associated with NLE in white and North American black populations.

OBJECTIVE

We sought evidence of a potential genetic disposition to NLE in mothers with a relatively homogeneous ethnic background.

METHODS

Class II human major histocompatibility complex HLA-DRB1, DQA1, DQB1, and DPB1 alleles were determined by polymerase chain reaction-restriction fragment length polymorphism in anti-Ro(SS-A)-positive mothers as well as in infants from seven Japanese families with siblings concordant or discordant for disease expression of NLE.

RESULTS

All seven mothers had two or three DQ alleles of DQA1 and DQB1 possessing specific amino acid residues, which are reportedly associated with anti-Ro(SS-A) autoantibody response in white and black populations. There was no class II HLA profile that distinguished disease manifestations of NLE in infants.

CONCLUSION

The HLA class II allele associations with anti-Ro(SS-A) autoantibodies that have been noted in other ethnic groups were also found in Japanese anti-Ro(SS-A)-positive mothers whose infants had NLE, suggesting shared susceptibility factors across racial barriers in maternal predisposition to Ro(SS-A) autoimmune response.

Oxygen delivery as a factor in the development of fatal postoperative complications after oesophagectomy

BACKGROUND

This study was designed to assess the impact of oxygen transport variables on outcome in 115 patients undergoing elective surgery for oesophageal carcinoma.

METHODS

Haemodynamic parameters were determined using a Swan-Ganz catheter in all patients on the day before operation, 6 h after operation, and daily for the first 4 days after operation.

RESULTS

Oxygen delivery and consumption at 6 h were significantly higher in survivors than in non-survivors. However, oxygen delivery and consumption in both groups did not differ significantly after postoperative day 1. Of 17 patients with oxygen delivery levels lower than 445 ml min-1 m-2 at 6 h, eight died in hospital. Oxygen delivery in patients who developed either an anastomotic leak or severe pneumonia was significantly lower 6 h after surgery. Lower levels of oxygen delivery preceded postoperative complications.

CONCLUSION

Oxygen delivery 6 h after oesophagectomy correlates with postoperative complications and may be a determinant of hospital mortality.

Single catheter technique of hepatic venous isolation and extracorporeal charcoal hemoperfusion for malignant liver tumors

BACKGROUND

A single catheter technique of hepatic venous isolation and charcoal hemoperfusion (HVI-CHP) using a 4-lumen/2-balloon (4L-2B) catheter was developed to perform high-dose intra-arterial chemotherapy of the liver. Herein we report the technique, safety, and pharmacokinetics of this system in comparison with the original double-balloon technique.

PATIENTS AND METHODS

Sixteen patients with malignant liver tumors were treated by hepatic arterial infusion (HAI) with adriamycin at a dose of 100 mg/m2 under HVI-CHP. Seven patients underwent HVI-CHP by the double-balloon technique (group A), in which filtered hepatic effluent and the rest of the inferior vena caval blood were separately drawn and returned to the left axillary vein. The other nine patients were treated by the single catheter technique (group B). In group B, hepatic effluent was isolated by balloon inflations and directed to filters through fenestrations of one major lumen of a 4L-2B catheter. The filtered blood was returned straight to the right atrium through the other major lumen of the catheter.

RESULTS

All patients in group A had a smooth stepwise induction of HVI-CHP, whereas one of nine patients in group B developed severe hypotension requiring interruption of HVI. The hepatic venous flow rate in group B during HVI-CHP was significantly higher than that in group A (P < 0.05). Systemic adriamycin exposure, as assessed by the area under the time concentration curve in systemic serum, was significantly higher in group A compared to that in group B (P < 0.01).

CONCLUSIONS

The single catheter technique is hemodynamically tolerable and feasible in the majority of patients with malignant liver tumors. In view of systemic drug exposure, the single catheter technique is superior to the original double-balloon technique.

Extranodal connective tissue invasion and the expression of desmosomal glycoprotein 1 in squamous cell carcinoma of the oesophagus

We investigated extranodal connective tissue involvement (ECTI) in 39 patients with oesophageal carcinoma. Both the primary tumour and ECTI were immunohistochemically examined using the monoclonal antibody 32-2B for desmosomal glycoprotein 1 (DG1). Connective tissue carcinoma deposits were identified as cells within small lymph nodes, as lymphatic or venous vessel invasion or as widespread invasion beyond the capsule of metastatic lymph nodes. These histological findings were present in at least one area in 20 of 39 patients (51.3%). DG1 immunostaining intensity by tumour was graded as DG1 (++), DG1 (+) or DG1 (-). DG1 (+) or DG1 (-) primary tumours demonstrated lymph node metastases and ECTI more frequently than DG1(++) tumours (P<0.05). Among 17 patients in whom DG1 immunohistochemistry was performed on ECTI, there were three DG1(++), five DG1(+) and nine DG1(-) patients. The DG1 expression of ECTI was equal to or less intense than the primary tumour. These results indicate that reduction or loss of DG1 expression may promote ECTI and lymph node metastases. One should be aware of the potential for ECTI in oesophageal carcinomas. In the future, adjuvant therapy may be advisable for some oesophageal carcinomas based on the phenotype of individual cancer cells, including expression of DG1.

[Antimicrobial activities of arbekacin against methicillin-resistant Staphylococcus aureus]

In order to evaluate antimicrobial activity of arbekacin (ABK), coagulase-type and minimum inhibitory concentrations (MICs) of ABK and other drugs were determined against 700 strains of methicillin-resistant Staphylococcus aureus (MRSA) that were obtained in our laboratory from 1990 to 1996, 7 years. The results are summarized as follows; 1. The MIC-distributions of ABK against 100 strains of MRSA obtained yearly did not show stochastically significant differences. 2. The coagulase-type distributions showed differences over the years. Coagulase-type II strains increased and type IV strains decreased, and MIC-distributions of ABK and other drugs were different according to coagulase-types. 3. The detection frequencies of ABK-resistant strains (MIC of ABK: > or = 12.5 micrograms/ml) were 2.0 approximately 8.0% through the years. The frequency reported in 1980 was equal to the frequency obtained in 1992 approximately 1993 in a nationwide survey. Coagulase-types II, IV and VII that were ABK-resistant strains were frequently obtained, and most of ABK-resistant strains were also highly resistant to gentamicin.

Lymph node and perinodal tissue tumor involvement in patients with esophagectomy and three-field lymphadenectomy for carcinoma of the esophagus

BACKGROUND

Lymph node metastasis is a definitive prognostic factor; however, perinodal fat tumor invasion has not been fully elucidated.

METHODS

Periesophageal nodes and the surrounding fibrofatty tissue obtained from 131 patients who underwent esophagectomy were examined.

RESULTS

Of 9,789 nodes removed, 645 (6.6%) demonstrated invasion and 143 (1.5%) showed perinodal involvement. Of 131 patients 97 (74.0%) had lymph node involvement and 43 (32.8%) had perinodal fat involvement. The incidence of perinodal tissue involvement correlated significantly with the number of nodes involved; 23 (42.6%) of 54 patients with a total of 1-8 nodes involved and 19 (95.0%) of 20 patients with 9 or more involved nodes had perinodal involvement. The 5-year survival for 33 patients without involved nodes or perinodal tissue extension was 59.7%, compared to 14.0% for 43 patients with perinodal fat involvement.

CONCLUSION

Perinodal tissue carcinoma into the periesophageal fibrofatty tissue was a decisive prognostic factor in patients with curative resection for esophageal carcinoma.

Nerve regeneration and origin of Schwann cells in peripheral nerve allografts in immunologically pretreated rats

For peripheral nerve allografts, the conditions for successful nerve regeneration and the possibility of transplanting Schwann cells were examined using a model of pretreated rats. Incomplete immunosuppression was achieved in recipient rats with donor red blood cell infusions given before allogeneic nerve grafting (RBC group). The origin of Schwann cells in the grafts was assessed by immunohistochemical staining from 1 week to 12 weeks after transplantation. In the RBC group, the replacement of donor Schwann cells by recipient cells was detected at 3-8 weeks, with the graft being filled with many of these cells at all times, and successful nerve regeneration was seen after 12 weeks on morphometric and electrophysiologic evaluations. In peripheral nerve allografts, pretreatment with donor-specific blood transfusion did not induce significant immunosuppression compared with allotransplantations of some tissues and organs. Clinically, if the state of immunosuppression can be controlled by RBC transfusion, it is possible that donor tissues may be replaced by recipient tissues and that nerves will regenerate successfully.

Viral dynamics of hepatitis C early after orthotopic liver transplantation: evidence for rapid turnover of serum virions

The pathogenesis of hepatitis C virus (HCV) infection is likely to be associated with viral replication in vivo, but little is known concerning the dynamics of HCV turnover. We performed serial measurements of serum HCV-RNA levels following orthotopic liver transplantation (OLT) in nine patients with HCV-positive cirrhosis. Serum HCV-RNA levels were determined by quantitative polymerase chain reaction before, immediately after, and for up to 1 month after OLT. There was a rapid decline in HCV-RNA levels from 3.1 +/- 1.3 x 10(5) copies/ mL (mean +/- SEM) preoperatively to 0.15 +/- 0.6 x 10(5) copies/mL on the first and 0.16 +/- 0.6 x 10(5) copies/mL on the second postoperative day (mean viral half-life, 4.0 +/- 0.5 h). Thereafter, HCV-RNA levels increased in all but one patient, and by postoperative day 8 reached 3.6 +/- 1.3 x 10(5) copies/mL, exceeding the preoperative levels irrespective of the use or not of rescue immunosuppressive therapy including steroid bolus administration. In most patients, serum virions continued to increase averaging 11.6 +/- 2.8 x 10(5) copies/mL on the 30th postoperative day. These findings indicate that the half-life of HCV is quite short, and that extrahepatic viral replication contributes little to the total virus pool in serum. Furthermore, the marked HCV replication beginning as early as the third postoperative day strongly suggests that the liver graft is rapidly reinfected by HCV after OLT.

Analysis of fetal rat liver using monoclonal antibodies

BACKGROUND

In previous studies, we developed several monoclonal antibodies (mAbs) against fetal and adult rat liver to analyze the hemopoietic microenvironment of the fetal liver during the gestational period. In this study, we have developed two new mAbs against fetal rat liver cells and have examined the characteristics at various gestational ages of fetal liver and of adult liver.

METHODS

The characteristics of these monoclonal antibodies were demonstrated by examining several tissues using immunohistochemical staining and flow cytofluorometry.

RESULTS

Monoclonal antibodies HAM10 and HAM11 were developed against fetal rat liver cells. These reacted with the cytoplasm of fetal and adult hepatocytes. HAM10 antigen expression was strong at approximately day 18 of gestation in the active period of hemopoiesis in fetal rat liver but was much lower in adult liver. HAM10 antigen expression also increased in liver after partial hepatectomy and was reduced abruptly to a normal level thereafter. HAM11 antigen expression in fetal liver was weaker than that of HAM10 antigen expression. The degree of HAM11 antigen expression increased as gestation proceeded, reaching a maximum in adult liver.

CONCLUSIONS

Both HAM10 and HAM11 antigens may play a role in the morphogenesis of hepatocytes and in the hemopoietic microenvironment for hemopoietic cells. Moreover, HAM10 antigen is may play a role in hepatocyte proliferation in the fetal liver, whereas HAM11 antigen may contribute to the maturation of fetal- to the adult-type hepatocytes.

Assessment of tumor invasion of the distal esophagus in carcinoma of the cardia using endoscopic ultrasonography

BACKGROUND AND STUDY AIMS

Esophageal invasion by carcinoma of the cardia may affect the surgical approach. Accurate assessment of esophageal invasion is difficult using endoscopy, computed tomography, or barium contrast radiography. The aim of the present study was to evaluate the use of endoscopic ultrasonography (EUS) in the prediction of esophageal invasion by carcinoma of the cardia.

PATIENTS AND METHODS

EUS (using a linear-array scanner) was carried out prospectively in 47 patients with carcinoma of the cardia who underwent subsequent surgical resection. The findings were correlated with the histopathological assessment of tumor infiltration in the esophagus in the resected specimen.

RESULTS

An absence of esophageal invasion was correctly predicted by EUS in 12 of 13 patients. Histopathologically confirmed invasion of the esophagus was correctly predicted in 32 of 34 patients. With a margin of error of 10 mm, the accuracy of EUS in predicting or excluding histologically confirmed invasion of the esophagus was 85.1% (40 of 47 patients). False-positive results with EUS occurred in patients with prominent edematous or fibrous changes in the distal esophagus; false-negative results with EUS were seen in patients with scattered infiltration of a small number of tumor cells into the mucosal or submucosal layer.

CONCLUSIONS

EUS can provide the surgeon with additional information on the extent of esophageal infiltration in patients with carcinoma of the gastric cardia, and can therefore assist in the selection of the surgical approach.

Ultrasonographic detection of lymph-node metastases in superficial carcinoma of the esophagus

BACKGROUND AND STUDY AIMS

The presence or absence of lymph-node metastasis is the single most important factor in determining the strategy for treating superficial carcinoma of the esophagus. In this study, ultrasound (US) and endoscopic ultrasonography (EUS) were used in the diagnosis of lymph-node metastases, and the accuracy and limitations of these methods were assessed.

PATIENTS AND METHODS

Prospectively, 37 patients with superficial esophageal cancer were studied by US and EUS before surgery, and the results were compared with the histological findings. Twelve of the patients had histologically confirmed lymph-node metastases. Ultrasonographic images of the lymph nodes were classified into three types, based on their boundaries and internal echoes.

RESULTS

The sensitivity, specificity, and accuracy of predicting mediastinal lymph-node metastasis by EUS diagnosis were 80.0%, 87.5%, and 86.5%, respectively. The sensitivity, specificity, and accuracy of US in the assessment of cervical and abdominal lymph-node metastasis were 71.4%, 86.7%, and 83.3%, respectively. In cases in which there was a solitary metastatic lymph node, the detection rate was higher than in cases with two or more positive nodes. Most metastatic lymph nodes correctly diagnosed by US and EUS were larger than 6 mm and had tumor involving more than one-third of their cross-sectional area.

CONCLUSIONS

In patients with superficial esophageal carcinomas, US is accurate in staging cervical and abdominal lymph nodes. EUS is accurate in staging mediastinal lymph nodes.

[Antimicrobial activity of cefodizime against clinical isolates]

In order to evaluate antimicrobial activity of cefodizime (CDZM), minimum inhibitory concentrations (MICs) of CDZM and control drugs were determined against clinical isolates collected from nation-wide medical institutions and in our laboratory from September to December of 1992 and from September to December of 1995. The results are summarized as follows: 1. Bacterial species with no or few strains resistant to CDZM included Streptococcus pyogenes, Haemophilus influenzae, Citrobacter koseri, Proteus mirabilis and Neisseria gonorrhoeae. The range of MIC values of CDZM against Klebsiella pneumoniae was spread. Other strains, Streptococcus pneumoniae, Moraxella subgenus Branhamella catarrhalis, Escherichia coli, Citrobacter freundii, Enterobacter spp., Serratia marcescens, Proteus vulgaris, Morganella morganii, Providencia spp., Peptostreptococcus spp. and Bacteroides fragilis group were resistant to cephems including CDZM. 2. The MIC90's of CDZM were 0.05 approximately 3.13 micrograms/ml against Streptococcus spp., H. influenzae, M. (B.) catarrhalis, E. coli, Klebsiella spp., P. mirabilis, N. gonorrhoeae and Peptostreptococcus spp. obtained in 1995 that were frequently found in daily treatment of infections. It appears that the effectiveness of CDZM was still relatively high against community-acquired infections. 3. Among H. influenzae isolates included imipenem (IPM)-resistant and norfloxacin (NFLX)-resistant strains. The MIC-range of CDZM against strains collected in 1995 including IPM-resistant and NFLX-resistant strains was < or = 0.025 approximately 0.1 microgram/ml, and MIC90 against these strains was 0.05 microgram/ml. CDZM showed strong antimicrobial activities against H. influenzae strains resistant to carbapenems and new-quinolones.

GB virus C infection in patients with chronic hepatitis B and C before and after liver transplantation

Recently, a novel virus, tentatively designated GB virus (GBV-C) was identified in patients with hepatitis. The frequency of this novel virus infection was therefore investigated in 58 patients with chronic hepatitis B virus (HBV) infection and in 74 patients with chronic hepatitis C virus (HCV) infection who had received orthotopic liver transplantation (OLT) because of decompensated liver cirrhosis. Before OLT, GBV-C sequences were found by reverse transcription nested polymerase chain reaction with primers derived from the helicase-like region in six (10%) of the HBV- and in six (8%) of the HCV-infected patients. Specificity of the polymerase chain reaction products was confirmed in eight of them by direct sequencing. Pretransplant GBV-6 viremia was associated with posttransplant viremia in 75% of patients. The comparison of GBV-C nucleotide and amino acid sequences within the helicase-like region revealed that pre- and posttransplant sequences differed only in 0-7 nucleotide exchanges, and with the exception of one, all of them were silent mutations. After OLT, 29% of the HBV- infected and 12% of the HCV-infected patients became GBV-C positive,indicating a high rate of "de novo" GBV-C infection. By correlating the GBV-C status with the frequency of the occurrence of graft hepatitis in both groups of patients, it became evident that posttransplant GBV-C viremia did not increase the risk for this clinical condition. However, we found a significantly higher percentage of hepatocellular carcinoma in patients with pre-OLT GBV-C/HCV coinfection compared with patients with HCV infection alone (5/6 vs. 16/68;P<0.01).

Administration of neutralizing antibody against rabbit IL-1 receptor antagonist exacerbates lipopolysaccharide-induced arthritis in rabbits

Endogenous IL-1 receptor antagonist (IL-1ra) may down-regulate part of IL-1 actions. We examined the participation of endogenous IL-1ra in the production of IL-1 beta in vitro. Macrophages cultured on adherent IgG produced a 100-fold molar excess of IL-1ra, compared with IL-1 beta. In the presence of a neutralizing monoclonal antibody (mAb) against rabbit IL-1ra, the production of antigenic IL-1 beta increased by 20-60%. Since the molar ratio of IL-1ra over IL-1 was 160- to 400-fold in synovial fluid (SF) of lipopolysaccharide (LPS)-induced arthritis, we examined the functional role of endogenous IL-1ra in the regulation of inflammatory responses. When measured in the presence of anti-IL-1ra mAb, masked IL-1 activity in SF became evident, with a 3- to 4-fold increment. The administration of anti-IL-1ra mAb with LPS into rabbit knee joints increased the IL-1 activity 4-fold and the production of antigenic IL-1 beta by 30-50%. The treatment also enhanced by 20-40% LPS-induced leukocyte infiltration and protein leakage. Therefore, endogenous IL-1ra apparently acts as a down-regulating factor for limiting deleterious effects of IL-1 by masking the biological activity and by inhibiting the production.