Inconsistent association of Epstein-Barr virus with CD56 (NCAM)-positive angiocentric lymphoma occuring in sites other than the upper and lower respiratory tract

We previously described nine cases of angiocentric lymphoma of a possible natural killer (NK)-cell lineage with a surface CD3-CD56+ phenotype occurring in sites other than the upper and lower respiratory tract. This study was performed to investigate the association of Epstein-Barr virus (EBV) with these lymphomas, using the polymerase chain reaction (PCR) for the presence of EBV-DNA, in situ hybridization (ISH) for EBV-encoded small RNAs (EBERs) and immunohistology for EBV-determined nuclear antigen-2 (EBNA-2) and latent membrane protein-1 (LMP-1) in paraffin sections. PCR and ISH produced almost identical results, and EBERs were identified in the nuclei of the lymphoma cells of three cases, two of which exhibited LMP-1 in the cytoplasm of tumour cells without EBNA-2 expression. Molecular genetic analysis revealed EBV to be incorporated into these three EBER-positive cases either clonally or biclonally. It was revealed by re-evaluation of their morphology with the established EBV status on each case that, in contrast to the rather variable and irregular cellular composition of the EBV-positive tumours, the EBV-negative tumours stood out because of their remarkably uniform 'blastoid' appearance, and could be grouped as blastic NK-cell lymphoma. The relationship of the EBV-positive cases with nasal NK-cell tumours has yet to be clarified.

Deterioration of urinary findings after tonsil stimulation in patients with IgA nephropathy

We studied whether urinary findings are affected by stimulation of tonsils in patients with IgA nephropathy. In 62 patients with IgA nephropathy and 20 patients with other renal diseases tonsils were stimulated by an ultra short wave for 10 min. Changes in amount of urinary protein, urinary sediment, blood leucocyte count, concentrations of serum IgA and serum secretory IgA were evaluated after tonsil stimulation. Forty of 62 patients with IgA nephropathy (65%) showed deterioration of urinary findings after the stimulation compared with 6 of 20 patients with other renal diseases (30%). The deterioration was significantly more frequent in IgA nephropathy than in other renal diseases (p <0.005). Previous episodes of gross hematuria following upper respiratory tract infections had occurred in 17 of 40 patients who showed deterioration of urinary findings after tonsil stimulation (43%) as against in 4 of 22 without deterioration (18%). The level of serum secretory IgA was higher in patients who showed deterioration of urinary findings after tonsil stimulation than in those who did not show it. Though tonsil stimulation increased blood leucocyte count it did not affect the concentrations of serum IgA or secretory IgA. It is concluded that tonsil stimulation often deteriorates urinary findings in patients with IgA nephropathy; therefore chronic tonsillitis may play a part in the pathogenesis of IgA nephropathy.

Evaluation of the protective effect of a novel prostacyclin analog on mesenteric circulation following warm ischemia

The protective effect of a novel prostacyclin (PGI2) analog, OP-2507, on mesenteric circulation was investigated in a canine warm ischemia model. In 20 mongrel dogs, the entire portion of the intestine supplied by the superior mesenteric artery (SMA) and drained by the superior mesenteric vein (SMV) was completely isolated, maintaining the blood and lymph vessels intact. Sixty or 120 min of complete warm ischemia (WI) of the intestine was induced by clamping SMA and SMV, followed by reperfusion for 120 min. Animals were divided into five groups (each n = 4): group 1, sham operation; group 2, 60 min WI; group 3, 120 min WI; group 4, 60 min WI with PGI2 analog administration; group 5, 120 min WI with PGI2 analog administration. The analog was administered at a rate of 6 micrograms.kg-1.h-1 immediately after laparotomy until the end of the observation period. Mean arterial pressure, SMA blood flow (SMABF), SMV pressure were monitored and total mesenteric vascular resistance (TMVR) was calculated. To evaluate the endothelial activation, endothelin, which is secreted from the endothelium under hypoxic stress, was assayed from blood samples of SMV. None of the animals showed significant changes in mean arterial pressure. In groups 2 and 3, SMABF decreased significantly to less than 60% of preoperative value (15 ml.kg-1.min-1) and TMVR significantly increased from 8.1 and 7.3 mm Hg.ml-1.kg.min before WI to 14.0 and 16.4 mm Hg.ml-1.kg.min after 120 min reperfusion, respectively, resulting in delayed hypoperfusion. In contrast, in groups 4 and 5, SMABF increased to over 100% of preoperative level, while TMVR declined from 7.8 and 8.4 mm Hg.ml-1.kg.min before WI to 6.2 and 6.3 mm Hg.ml-1.kg.min after 120 min reperfusion. After 60 min reperfusion, SMABF and TMVR showed a significant difference between the treated and nontreated groups. Only in group 3, high endothelin concentrations (over 20 pg/ml) were observed even after 120 min reperfusion. It was concluded that the PGI2 analog was able to suppress the endothelial activation and the disturbance of mesenteric circulation caused by WI and reperfusion.

Non-Hodgkin's lymphoma of the thyroid. A clinical study of twenty-two cases

Non-Hodgkin's lymphoma (NHL) of the thyroid gland is a rare disease. In the present study, the survival rate and characteristics were retrospectively analyzed in 22 patients with stage IE and IIE thyroid NHL treated with radiotherapy with or without combination chemotherapy. Seventeen NHL had histological evidence of lymphoma of mucosa-associated lymphoid tissue (MALT) type. The 5-year survival rate was 85% in all patients, with 100% and 63% respectively, for stage IE and stage IIE patients. The highly significant factor correlated with decreased determinate survival was concomitant stridor.

Tissue Factor Pathway Inhibitor Production by Human Mesangial Cells in Culture

Fibrin formation within the glomeruli has been observed in various forms of human and experimental glomerulonephritis and it may play an important role in progressive glomerular injury. Furthermore it has been hypothesized that glomerular fibrin deposition may occur through activation of either the intrinsic or extrinsic coagulation pathway. It has been demonstrated that a procoagulant activity (PCA) which is compatible with tissue factor is present in the glomeruli and becomes increased in human proliferative glomerulonephritis and in animal models of nephritis. Tissue factor pathway inhibitor (TFPI) regulates the extrinsic pathway of blood coagulation through its ability to inhibit tissue factor activity. TFPI is present in plasma and in platelets, and it is now thought to be produced mainly by endothelial cells. We examined whether human mesangial cells (HMC) could produce TFPI and attempted to clarify regulatory factors which affect TFPI production. Cultured HMC were used and TFPI in the cell supernatants was measured by ELISA using a specific antibody. Cultured HMC showed the production of TFPI. Immunoblot analysis revealed 40 kD protein of TFPI. The concentration of TFPI was significantly increased following the incubation with thrombin and heparin, including low molecular weight heparin, in a dose- and time-dependent manner. However, fetal calf serum, phorbol myristate acetate, lipopolysaccharide, IL-1β and tissue factor did not stimulate TFPI synthesis. Our data show that cultured HMC have the ability to produce TFPI which inhibits fibrin formation. It is possible that thrombin-induced enhancement of TFPI synthesis may be caused by the autoregulatory system of blood coagulation and that with heparin it may represent another anticoagulatory effect of heparin.

Effect of nicorandil on abnormal coronary flow reserve assessed by exercise 201Tl scintigraphy in patients with angina pectoris and nearly normal coronary arteriograms

The purpose of the present study is to assess the effect of nicorandil, a coronary vasodilator with a mechanism of potassium channel opening, on the abnormal myocardial 201Tl perfusion evoked by exercise. Eleven patients who had a history of typical angina, positive exercise electrocardiograms, positive 201Tl scintigraphy, nearly normal coronary arteriograms, and negative coronary vasospasm underwent exercise 201Tl scintigraphies under no medication (baseline test) and administration of nicorandil (nicorandil test). 201Tl was injected at a matched workload in both tests. Nicorandil did not alter heart rate, blood pressure, or the rate-pressure product at the end of the exercise, but it significantly improved the extent score from 0.37 +/- 0.22 to 0.20 +/- 0.15 (p < 0.05) and the severity score from 33.9 +/- 32.2 to 13.5 +/- 16.4 (p < 0.05), and also significantly hastened the 201Tl mean washout rate from 30.5 +/- 14.8% to 37.4 +/- 13.1% (p < 0.05). Anginal symptoms disappeared in 3 of 5 cases and ST depression improved in 5 of 7 cases after nicorandil. We conclude that nicorandil augments coronary flow reserve, possibly due to a reduction of vasotone in the small coronary arteries.

Nuclear morphometry for improved prediction of the prognosis of human bladder carcinoma

BACKGROUND

Histologic grade and clinical stage generally are used for estimating the prognosis of bladder carcinoma. However, both methods have been reported to have a rather low reproducibility and to be unsatisfactory for predicting the recurrence and progression of superficial bladder carcinoma. Recently, nuclear morphometry was used to quantitate the malignant potential of cancer cells in a more objective and reproducible manner. The authors quantitatively analyzed the malignant potential of bladder carcinoma at initial presentation using a combination of several nuclear morphometric variables.

METHODS

The subjects were 156 patients with previously untreated bladder carcinoma. Three morphometric variables were measured in each subject: the mean nuclear volume (MNV), the nuclear roundness factor (NRF), and the variation of nuclear area (VNA).

RESULTS

Univariate analysis showed that MNV and NRF were significant prognostic indicators for survival (MNV, P < 0.0001; NRF, P = 0.008). In addition, MNV was a prognostic indicator for tumor recurrence (P = 0.001), whereas MNV and NRF were prognostic indicators for invasive progression (MNV, P = 0.02; NRF, P = 0.009). For accurate prediction of the prognosis of patients with bladder carcinoma, a prognostic score, a recurrence score, and a progression score were designed using the coefficients of MNV and NRF in a proportional hazards model. The prognostic score clearly divided the patients into two different groups with 5-year survival rates of 88% and 64% (P = 0.0002). In addition, patients with superficial bladder carcinoma and a low recurrence score had a significantly higher 5-year recurrence free rate than those with a high recurrence score (40% vs. 23%, P = 0.0004), and the 5-year progression free rate of patients with a low progression score was significantly higher than that of those with a high progression score (98% vs. 73%, P = 0.0006).

CONCLUSIONS

These findings suggest that nuclear morphometry is a reliable technique with which to identify prognostic indicators for human bladder carcinoma. A combination of several nuclear morphometric variables provides a more accurate indication of prognosis than any single parameter.

Tumorigenicity of human T-cell leukemia virus type I-infected cell lines in severe combined immunodeficient mice and characterization of the cells proliferating in vivo

The mechanism involved in leukemogenesis and neoplastic cell growth of adult T-cell leukemia (ATL) still remains unclear. We examined the tumorigenicity of human T-cell leukemia virus type I (HTLV-I)-infected cell lines in an in vivo cell proliferation model using severe combined immunodeficient (SCID) mice. Eleven HTLV-I-infected cell lines were injected into SCID mice and we found that 4 of them were capable of proliferating in SCID mice. Three of four transplantable cell lines are derived from the leukemic cell clone and 6 of 6 HTLV-I-infected cell lines of nonleukemic cell origin could not engraft in SCID mice. Interestingly, it was shown that some HTLV-I-infected and interleukin-2 (IL-2)-dependent cell lines could successfully engraft in SCID mice. The expression of IL-2 mRNA was not detected in these cell lines growing either in vivo or in vitro. HTLV-I viral products were not detected in 3 of 4 transplantable cell lines proliferating in vivo. Peripheral blood T cells immortalized by introduction of tax gene of HTLV-I were found to have no tumorigenic potential in SCID mice. These data suggest that (1) HTLV-I-infected cell lines of nonleukemic cell origin do not have enough leukemogenic changes to acquire the tumorigenic potential in SCID mice; (2) the IL-2 autocrine mechanism is not directly involved in the tumor cell growth; (3) viral gene expression is not needed for the maintenance of neoplastic cell growth; and (4) the expression of tax gene is not sufficient for the neoplastic cell growth in vivo.

Anaplastic large cell lymphomas expressing the novel chimeric protein p80NPM/ALK: a distinct clinicopathologic entity

Anaplastic large cell lymphoma (ALCL) is a subtype of non-Hodgkin's lymphoma characterized by the CD30+ large neoplastic cells and sometimes carries a t(2;5)(p23;q35). Recently, we found a novel hyperphosphorylated 80-kD protein tyrosine kinase, p80, in ALCLs with t(2;5). Subsequent cDNA cloning showed p80 to be a fusion protein of two genes, the novel tyrosine kinase gene and the nucleophosmin gene, in accordance with the sequence of the NPM/ALK gene (Morris et al, Science 263:1281, 1994). Meanwhile, the clinicopathologic features of p80-carrying ALCLs have remained unclear. Paraffin sections of 105 cases of ALCL were immunostained using anti-p80 antibody, and 30 of them were shown to express p80. Clinicopathologic comparison between p80-positive and -negative ALCLs showed that p80-positive cases occurred in a far younger patient age group (16.2 +/- 12.9 years; p80-negative cases, 51.0 +/- 22.3 years; P < .0001) and the patients showed a far better 5-year survival rate (79.8%; p80-negative group, 32.9%; P < .01). These data showed that p80-positive ALCL is a distinct entity both clinically and pathogenetically and should be differentiated from p80-negative ALCL.

Primary malignant lymphoma of the central nervous system--report of four long-term survivors

Four of 47 patients treated between 1977 and 1993 for histologically confirmed primary malignant lymphoma of the central nervous system (non-Hodgkin's type of B-cell origin) achieved long-term survival for more than 5 years with a good quality of life. Three have remained disease-free for 9-12.5 years. The fourth achieved complete remission for more than 5 years before death from tumor recurrence. All four patients were treated with a standard therapeutic regimen, consisting of radiotherapy (50-60 Gy local and 30-40 Gy whole brain irradiation) followed by four to six courses of chemotherapy with cyclophosphamide, vincristine, adriamycin, and prednisolone at 4- to 8-week intervals. No further treatment was performed after remission had been obtained. No specific predictors for long-term survival including sex, age, tumor location, multiplicity of lesions, histology, or treatment modality was identified. All four patients showed an immediate tumor response to radiation. We recommend chemotherapy at increasing intervals as part of the post-therapeutic management of long-term, disease-free patients.

Cardiac involvement in a family with Becker muscular dystrophy

We report a family with Becker muscular dystrophy (BMD) presenting with cardiac involvement. The proband was a 41-year-old Japanese man who was hospitalized with exertional dyspnea and muscle weakness. Cardiac examination showed findings consistent with dilated cardiomyopathy. Dystrophin immunohistochemical analysis showed a discontinuous patchy staining pattern in cardiac and skeletal muscles biopsied from the proband. His brothers had high creatine kinase (CK) activity and abnormal electrocardiogram. Dystrophin gene analysis revealed that the proband and his brothers had G-to-T transversion at the terminal nucleotide of exon13. We conclude that the mutated dystrophin gene may cause cardiac involvement as a symptom precedent to skeletal muscle involvement.

Hepatitis C virus infection and membranoproliferative glomerulonephritis in Japan

The prevalence of hepatitis C virus (HCV) infection was determined in 146 adult patients with various types of glomerulonephritis and renal diseases monitored between 1990 and 1993. Serum HCV antibody (HCV Ab) was evaluated, and positive cases were tested for HCV RNA by polymerase chain reaction. HCV infection was present in 1 (1.7%) of 58 cases of immunoglobulin A nephropathy, 0 (0%) of 14 cases of lupus nephritis, 0 (0%) of 12 cases of minimal change nephrosis, and 0 (0%) of 28 cases of other renal diseases, which is similar to the 2% prevalence observed in healthy blood donors in Japan. In contrast, HCV Ab was observed in 2 (8.3%) of 24 cases of membranous nephropathy and 6 (60%) of 10 cases of membranoproliferative glomerulonephritis (MPGN) Type I. The prevalence of HCV infection in MPGN patients was significantly higher than the frequency of HCV infection observed in the other patients with renal diseases (P < 0.001). HCV RNA was present in all cases in which HCV Ab was present. The six patients with HCV-MPGN were similar to the four patients with idiopathic MPGN with respect to age, presence of nephrotic syndrome, and renal dysfunction, but had a higher incidence of liver dysfunction, cryoglobulinemia, rheumatoid factor, and hypocomplementemia (low C3). HCV infection is present in a large percentage of patients with MPGN in Japan and clinically may differ slightly from other cases of MPGN.

Papillary serous carcinoma of the peritoneum in women. A clinicopathologic and immunohistochemical study

BACKGROUND

Papillary serous carcinoma of the peritoneum (PSCP) is a primary peritoneal tumor in women that histologically resembles papillary serous carcinoma of the ovary (PSCO). Recognition of PSCP as an entity is controversial, as is the histogenesis, histopathologic differential diagnosis, and treatment.

METHODS

Ten cases of PSCP retrieved from the pathology files of 4 hospitals in Kyoto and Nara, Japan, were studied clinicopathologically and immunohistochemically.

RESULTS

Patient ages at presentation ranged from 40 to 74 years (median, 56 years). All patients were Asian (Japanese). None of the patients had a history of asbestos exposure. Most of the patients had abdominal swelling, ascites with positive cytology, and elevated serum CA125. At surgery, omental tumors with dissemination to the abdominal and pelvic peritoneum were found in all patients. The histology was similar to that of Grade 2 to 3 PSCO. Immunohistochemical studies using a panel of monoclonal antibodies against carbohydrates showed that Lewis Y is a good marker, in addition to S-100, placental alkaline phosphatase, CA125, and CD15 for separating PSCP from malignant mesothelioma (MM). With cytoreductive surgery and cisplatin-based combination chemotherapy and in some cases adoptive immunotherapy and radiation, a median survival of 27 months and a 5-year survival rate of 27% were attained. One patient with Grade 3 tumor has survived for more than 6 years after surgery.

CONCLUSIONS

(1) Papillary serous carcinoma of the peritoneum is a definite clinicopathologic entity; (2) immunohistochemistry is a useful tool for distinguishing PSCP from MM; (3) cytoreductive surgery and cisplatin-based combination chemotherapy with other adjunct therapies such as immunotherapy and radiation may improve patient survival in PSCP.

The role of cardiac output response in blood flow distribution during exercise in patients with chronic heart failure

The relationship between blood flow in the working leg and cardiac output (Q) response was determined for patients with chronic heart failure. The ratio of leg blood flow (LBF) to Q (LBF/Q) at the same workload during submaximal exercise was significantly different in three groups of patients classified by peak cardiac index: it was 0.22 +/- 0.08 in the 'satisfactory' Q group vs 0.33 +/- 0.09 in the moderate Q group, and 0.38 +/- 0.08 in the poor Q group (P < 0.01) in the first stage of exercise. delta LBF/delta Q, the slope of change in leg blood flow to Q from rest to peak exercise, was significantly larger in the poor Q group than in the satisfactory Q group (P < 0.01). The intergroup arteriovenous oxygen difference (AVO2D) in organs other than the leg was large, while that in the working leg was small. Leg vascular resistance at submaximal workload was similar in the three groups, but vascular resistance in other organs was significantly higher in the poor Q group than in the satisfactory Q group (P < 0.001). These findings suggested that metabolic vasodilating stimuli in the working leg attenuated excessive vasoconstriction and caused a shift in blood flow from other organs to the working leg under conditions of severely reduced Q response.

Synchronous presentation of Epstein-Barr virus-associated Hodgkin's disease and adult T-cell leukemia/lymphoma (ATLL) in a patient from an endemic area of ATLL

We report a patient from an endemic area of adult T-cell leukemia/lymphoma (ATLL), who developed lymphoma with features characteristic of Hodgkin's disease (HD). Large atypical Reed-Sternberg/Hodgkin's cells (RS/H cells) had a CD3-CD15+CD20-CD30+CD45RO- immunophenotype. Epstein-Barr virus (EBV) latent membrane protein and EBV-encoded small RNA were detected in the RS/H cells. The patient received C-MOPP/ABVD chemotherapy for the HD resulting in a partial response. However, relapse occurred and he died of disease progression associated with serious bacterial infection. Although serial lymph node biopsies revealed consistent presence of the EBV-positive RS/H cells, the background small lymphocytes showed progressive increase in pleomorphism and nuclear irregularity. The lymphocytes had the T-cell phenotype, CD3+CD4+CD7-CD8-. Southern blot analysis using DNA probes for the human T-cell lymphotrophic virus-I (HTLV-I) and the T-cell receptor beta-chain gene demonstrated expansion of the HTLV-I infected monoclonal T-cells with the disease progression. We concluded that the patient synchronously presented two independent lymphoproliferative disorders; EBV-associated HD and ATLL resulting from HTLV-I infection.

Distribution of Tn antigen recognized by an anti-Tn monoclonal antibody (MLS128) in normal and malignant tissues of the digestive tract

Alterations in the normal glycosylation process are often associated with oncogenic transformation. Using an anti-Tn monoclonal antibody, MLS128, we have investigated the immunohistochemical localization of Tn antigen in normal and malignant tissues of the digestive tract. In normal tissues, MLS128 was immunoreactive with the squamous epithelium of the esophagus and was weakly reactive with the columnar epithelia of the stomach, duodenum, colon, bile duct and pancreatic duct. In malignant tissues, positive immunostaining was detected with high frequency (75%-100%) in carcinomas of the esophagus, stomach colon, biliary tract and pancreas, whereas 2 of 11 (18%) hepatocellular carcinomas were positive. Tn antigen was detected in the upper two-thirds of the normal squamous epithelium, and was often detected in squamous cell carcinomas with cancer pearls (keratinization). These results suggest that the expression of Tn antigen is related to the differentiation of squamous epithelium, or to keratinization. In normal columnar epithelial cells. Tn antigen was localized mainly to the Golgi area. This intracellular localization was preserved in well-differentiated papillary adenocarcinomas of the colon, but was lost in most cases of tubular adenocarcinomas.

The slow progression of hepatic fibrosis in intrahepatic cholestasis as compared with extrahepatic biliary atresia

It has been shown that the progression of hepatic fibrosis in intrahepatic cholestasis (IHC) is not so prominent as in extrahepatic biliary atresia (EHBA), and that the biosynthetic activity of collagen increases along with the fibrotic disease process. We conducted immunohistochemical and ultrastructural studies on the distribution of collagen types III and IV and of alpha-actinin in the smooth musculature in liver specimens obtained from 4 patients with IHC and 14 patients with EHBA in liver transplantation from living related donors (LRLT). A recently developed sandwich enzyme immunoassay (EIA) was used to determine serum concentrations of type IV collagen, laminin and prolyl 4-hydroxylase (PH) in the patients before and after LRLT. Pathological study showed that the excessive deposition of type IV collagen in the perisinusoidal walls resulted in a clearly developed basal membrane beneath the sinusoidal endothelial cells, so-called sinusoidal capillarization. In the fibrous septa of IHC, fibrogenesis was apparently lower than in EHBA, since collagen deposition and myofibroblast proliferation were not so prominent compared to EHBA. Serum type IV collagen, laminin and PH increased in IHC, although not so markedly as in EHBA, and returned to normal within 5 weeks after successful LRLT. In conclusion, it is suggested that an increased level of serum type IV collagen reflects the de novo synthesis of basal membrane components, and that the determination of their serum levels by EIA can be utilized for the differentiation of the specific fibrogenic activity in each disease, and for monitoring patients before and after liver transplantation.

Radiofrequency catheter ablation of accessory atrioventricular pathway in Wolff-Parkinson-White syndrome

Eighty patients with manifest or concealed Wolff-Parkinson-White (WPW) syndrome underwent catheter ablation of 86 accessory pathways (AP) using radiofrequency current. There are 65 AP located on the left side and 21 on the right side of the heart. The atrioventricular reciprocating tachycardia was previously documented in 77 patients and atrial fibrillation with a rapid ventricular response in 21 patients. Ablation was attempted via a catheter positioned at the atrial aspect of the tricuspid annulus in patients with a right-sided AP and via a catheter positioned in the left ventricle directly below the mitral annulus in patients with a left-sided AP. AP conduction was permanently abolished in 82 of the 86 pathways (95%). The number of radiofrequency current applications for these 82 successfully ablated AP was 7.6 +/- 0.9. Of the 65 left-sided and 21 right-sided AP, 62 (95%) and 20 AP (95%) were successfully ablated, respectively. The current application to the right-sided AP was 16.7 +/- 2.2, which was greater than that to the left-sided one (4.7 +/- 0.6, p < 0.001). No serious complication was observed in any case. Catheter ablation of AP using radiofrequency current is an effective and safe therapeutic modality for patients with symptomatic WPW syndrome.

Detection of homing, proliferation, and infiltration sites of adult T cell leukemia cells in severe combined immunodeficiency mice using radiometric techniques

To clarify the mechanism of in vivo proliferation of adult T cell leukemia (ATL) cells, we examined the organ distribution of ATL-43T cell line cells derived from original leukemic cells in severe combined immunodeficiency (SCID) mice using radiometric techniques. First, we injected 111In-oxine-labeled ATL-43T cells into SCID and CB17 mice. On day 6, significant accumulation of radioactivity was found in the spleen and thymus of SCID mice (33.3 +/- 9.4 and 10.0 +/- 3.6% injected dose/g of tissue [%ID/g], respectively) in comparison with that in CB17 mice (19.1 +/- 2.5 and 3.7 +/- 0.9%ID/g, respectively). Next, we injected radiolabeled anti-Tac monoclonal antibody (MoAb) recognizing human interleukin-2 receptor (IL-2R) alpha chain or isotype-matched control MoAb RPC5 in SCID mice bearing ATL-43T cells 4 weeks after cell inoculation. The amounts of radioactivity found in the spleen and thymus of SCID mice injected with 125I-labeled anti-Tac MoAb (22.5 +/- 6.9 and 22.8 +/- 9.6 %ID/g, respectively) were significantly higher than those in the corresponding organs of SCID mice injected with 125I-labeled RPC5 MoAb (12.0 +/- 5.1 and 7.5 +/- 4.6 %ID/g, respectively). Similar results were obtained with 111In-labeled anti-Tac MoAb. These results were consistent with the histological findings of SCID mice bearing ATL-43T cells, indicating that ATL-43T cells infiltrated preferentially into the lymphoid organs, such as the spleen and thymus, and proliferated there. Thus, the radiometric techniques employed in this study were very useful to evaluate the proliferation sites of ATL-43T cells in SCID mice. Furthermore, this murine model could give us an opportunity to test the feasibility of therapeutic application of radiolabeled anti-Tac MoAb.

Membranoproliferative glomerulonephritis associated with hepatitis C virus infection responsive to interferon-alpha

A 42-year-old man with hepatitis C virus infection, cryoglobulinemia, hypocomplementemia, and nephrotic syndrome is reported. The kidney biopsy showed membranoproliferative glomerulonephritis. The patient was treated with interferon-alpha for 2 months. After the treatment, serum hepatitis C virus RNA became negative and nephrotic syndrome remitted. Repeat biopsy of the kidney revealed an improvement in renal histology. This case confirms an association between hepatitis C virus infection and membranoproliferative glomerulonephritis and the usefulness of interferon-alpha for treatment.

Radiofrequency catheter ablation of concealed atrio-His bypass tract involved in paroxysmal supraventricular tachycardia

In a patient with paroxysmal supraventricular tachycardia and without any evidence for preexcitation syndrome or dual atrioventricular (AV) nodal pathways, the tachycardia reentry circuit consisted of the AV node as an antegrade limb of the circuit and a concealed atrio-His bypass tract located in the posterior septum as a retrograde limb. During the tachycardia, the atrial potentials in the septal region and coronary sinus were inscribed in the QRS complex, and the earliest atrial activation site was located in the posterior septum. Ventricular extrastimulation at critically short intervals reproducibly demonstrated a ventriculo-His-atrial activation sequence with the same earliest retrograde atrial activation site as that during the tachycardia. Radiofrequency energy (20 W) was applied to this earliest activation site during ventricular pacing, which resulted in complete ventriculoatrial block within 2 seconds after energy application. The antegrade AV conduction property was not affected and the tachycardia was no longer induced. The patient has been free from tachycardia attack for a follow-up period of 8 months. Therefore, radiofrequency catheter ablation for an atrio-His bypass tract is feasible without inducing any AV conduction disturbance.

Lactate threshold is not an onset of insufficient oxygen supply to the working muscle in patients with chronic heart failure

It has been argued that the lactate threshold (LT) serves as an index to reflect circulatory insufficiency in transporting oxygen during submaximal exercise in patients with chronic heart failure (CHF). We examined whether or not the LT was related to an insufficient oxygen supply in patients with CHF. Sixty-nine patients were divided by NYHA classification. All underwent invasive cardiopulmonary exercise testing. The rate of increase in oxygen delivery (O2D) versus VO2 (delta O2D/delta VO2) was significantly lowered when work rate exceeded LT, that is, 1.32 +/- 0.35 to 1.05 +/- 0.37 (p < 0.01), 1.22 +/- 0.40 to 0.98 +/- 0.40 (p < 0.05), and 1.04 +/- 0.26 to 0.78 +/- 0.39 (p < 0.05) in NYHA classes I, II, and III, respectively. However, the rate of increase in leg O2D versus leg VO2 (delta LO2D/delta LVO2) did not change, that is, 1.25 +/- 0.20 to 1.29 +/- 0.20 (NS), 1.27 +/- 0.23 to 1.21 +/- 0.28 (NS), and 1.19 +/- 0.24 to 1.15 +/- 0.17 (NS) in classes I, II, and III, respectively. Leg venous PO2 was significantly different among three groups, that is, 23.7 +/- 3.4 mmHg, 23.2 +/- 2.8 mmHg, and 20.1 +/- 2.3 mmHg (p < 0.001), respectively. Thus, the oxygen supply to the working muscle did not become insufficient when work rate exceeded LT, and the LT occurred at different levels of leg PO2. It was concluded that the LT was not a result of anaerobiosis in patients with CHF.