Thoracoscopic parasternal lymph node dissection for the staging of breast cancer

With the advent of advanced thoracoscopic techniques, new applications have been expanding their roles in thoracic surgery. The aim of this paper is to introduce our new thoracoscopic approach in performing parasternal lymph node dissection of advanced breast cancer for its staging. This technique does not need the removal of any costal cartilage which is usually done in the conventional classical technique after radical mastectomy. Thoracoscopic procedure, in which wide and complete parasternal lymph node dissection is done, is minimally invasive and easy to perform. Therefore, the thoracoscopic technique may be a suitable alternative to the conventional approach in the future.

Meningioma showing VHL gene inactivation in a patient with von Hippel-Lindau disease

The genetic mechanism of the tumorigenesis of meningioma in conjunction with von Hippel-Lindau (VHL) disease is unclear. The authors present a case of VHL disease associated with a posterior fossa meningioma and with multiple cerebellar hemangioblastomas. A germline mutation of the VHL gene and loss of heterozygosity on the VHL gene locus in 3p were detected in the meningioma. Tumorigenesis of a meningioma associated with VHL disease could be caused by inactivation of both alleles of the VHL gene.

Bone growth oscillation: longitudinal metabolic process of bone growth in congenital adrenal hyperplasia and nonendocrine short stature

To clarify the longitudinal metabolic process of bone growth in children, we observed the relationship between the level of serum osteocalcin (OC), a marker of bone metabolism, and growth velocity in 10 prepubertal patients with congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency and 9 prepubertal patients with nonendocrine short stature (NESS), but no major hormonal abnormalities influencing bone metabolism. Observations were made every 6 months over a 7-year period. In patients with CAH who exhibited a wide variation in growth velocity during the course of the investigation, the levels of OC fluctuated over a wide range, suggesting metabolically variable bone growth. In contrast, in patients with NESS who exhibited a relatively stable growth velocity, the OC level remained within a narrow range, suggesting metabolically stable bone growth. The meaning of such divergent metabolic processes of bone growth observed in CAH and NESS and its relationship to actual bone structure or bone intensity should be further investigated.

A novel autoimmune pancreatitis model in MRL mice treated with polyinosinic:polycytidylic acid

In this study we established a new animal model for exploring the pathogenesis of autoimmune pancreatitis. We have found previously that MRL/Mp-+/+(MRL/+) mice develop pancreatitis spontaneously by an autoimmune mechanism but only when they are more than 34 weeks old. Because this disease might be a model of multi-factorial diseases controlled by genetic and environmental factors, beginning at 6 weeks old, we injected polyinosinic:polycytidylic acid (poly I:C) into MRL/+ mice and in addition, into MRL/Mp mice bearing the Fas deletion mutant gene, lpr (MRL/lpr). Poly I:C induced chronic severe pancreatitis in all the MRL/+ mice and to a lesser extent in the MRL/lpr mice by 18 weeks of age. There was no pancreatitis in control mice of both strains at the same age. Other than chronic pancreatitis, no severe autoimmune diseases were observed in MRL/+ mice. Immunohistochemical examinations revealed predominant infiltration of CD4+ T cells and Mac-2+ activated macrophages in the pancreatic lesions. Splenic expression of the mRNAs for TNF-alpha and IL-10, which is known to suppress the development of pancreatitis, were increased in both strains of mice. These findings suggest that an MRL strain of mice treated with poly I:C might be a good model for developing new approaches to the study of the pathogenesis of autoimmune pancreatitis.

Effects of preconditioning on ischemia/reperfusion injury of hepatocytes determined by immediate early gene transcription

Ischemia reperfusion (I-R) of the liver induces various events leading to cell death (apoptosis) and subsequent cells proliferation. Recent experimental studies have described the protective effect of ischemic preconditioning (IPC) on I-R injury of the liver. However, the mechanisms involved in this protection remain unknown. The protein products of immediate early genes (IEGs) behave as crucial transcriptional regulators not only in apoptosis but also in cell proliferation. Here, we evaluated the effects of IPC on IEG transcription after I-R injury, using a rat liver I-R injury model. Injury to hepatocytes was evaluated by measuring serum levels of aspartate transaminase (AST), alanine transaminase (ALT), and lactate dehydrogenase (LDH) and that to endothelial cells by plasma concentration of hyaluronic acid (HA). The extent of necrosis was evaluated by H&E staining, while cell proliferation and apoptosis were evaluated by proliferating cell nuclear antigen (PCNA) and terminal deoxy(d)-UTP nick end labelling (TUNEL) staining, respectively. Alterations in the transcription of IEGs (c-fos and c-jun) were examined by Northern blotting. Rats subjected to 40-min liver ischemia, preceded by 10-min preconditioning, showed significantly lower AST, ALT, LDH, and HA levels at 6 h after I-R than untreated animals (P < 0.05; n at least 5 rats per group). The percentage of necrotic areas at 24 h after I-R was significantly lower in IPC-treated animals than in the controls. The numbers of apoptotic cells at 24 h after I-R and the numbers of PCNA-positive cells at 24 and 48 h after I-R were significantly lower in IPC-treated rats than in controls. Transcription levels of IEGs were low in IPC-treated rats, particularly c-jun at 1 and 1.5 h after I-R (P < 0.05). Our results indicate that IPC provides a significant protective effect on for liver cells against I-R injury and that its effect is evidenced by a significant decrease in the transcription levels of IEGs following the insult.

[Clinical significance and interpretation of red cell enzyme analyses]

Red cells have a life span of approximately 120 days and disturbances at biochemical pathways such as glycolysis, pentose phosphate shunt, nucleotide metabolism or glutathione synthesis/reduction systems lead to premature cell death, i.e. hemolysis. Red cell enzyme analysis is useful for screening for an enzyme defect which is responsible for hereditary nonspherocytic hemolytic anemia (HNSHA). Further clinical significance of red cell enzyme assay includes the diagnosis of paroxysmal nocturnal hemoglobinuria, methemoglobinemia, Diamond-Blackfan anemia, severe combined immune deficiency, glycogen storage disease, etc. Since several age-dependent enzymes are known, careful evaluation of enzyme activities is required if reticulocyte counts are elevated. It should be noted that deficiency of an isozyme may be masked by activity derived from another isozyme. Recent progress in the molecular genetics of red cell enzymopathies and protein structure-function mechanisms enable us to diagnose "enzyme deficiency" at DNA level.

Induction of immediate early genes after partial hepatectomy in cholestatic liver

The protein products of immediate early genes (IEGs) behave as transcriptional regulators and play an important role in the regulation of gene expression associated with liver cell proliferation and apoptosis. The aim of this study was to examine whether the transcription of IEGs was induced by obstructive jaundice during liver regeneration after 70% partial hepatectomy, and to examine their association with animal survival, cell proliferation, and apoptosis. Obstructive jaundice (OJ) was induced in rats by common bile duct ligation (CBDL), and 70% partial hepatectomy was performed 5 days after CBDL (OJ group). Changes in the induction of the IEGs, c-fos and c-jun, were compared between control and OJ groups in relation to survival before and after partial hepatectomy. Cell proliferation and apoptosis were evaluated by proliferating cell nuclear antigen (PCNA) immunohistological staining and by an in situ TdT-mediated d-UTP-digoxigerin nick-end labeling (TUNEL) method. The 2-week survival in the OJ group (2/7) was significantly less that of the sham operation (control) group (7/7). Enhanced induction of IEGs was evident in the OJ group after partial hepatectomy compared with findings in the control group. The PCNA-labeling index (LI) in the OJ group was increased after partial hepatectomy, but only minimally, compared with that in control animals. Apoptotic cells appeared in bile ducts and surrounding hepatocytes after partial hepatectomy in the OJ group, although apoptotic cells were rare in the control group. IEG transcription does occur after partial hepatectomy in jaundiced liver but it is enhanced and sustained, and leads to apoptosis rather than leading to the efficient proliferation of hepatocytes.

Cerebrovascular reactivity to acetazolamide in alert patients with cerebral infarction: usefulness of first-pass radionuclide angiography using 99m Tc-HMPAO in monitoring cerebral haemodynamics

Cerebral blood flow (CBF) and cerebrovascular reactivity (CVR) were studied in 75 patients with cerebral infarction. All patients were alert with the symptoms of hemiparesis and/or aphasia, and were divided into two groups: 42 patients had occlusion or stenosis of >75% at the internal carotid artery or main trunk of middle cerebral artery; and 33 patients did not. Hemispheric mean CBF was measured by performing first-pass radionuclide angiography using 99mTc-hexamethylpropylene amine oxime. CVR was measured as the percentage change from the baseline mean CBF value after the administration of 500 mg acetazolamide. The CVR in both groups was significantly impaired (5.2+/-6.3%, P<0.001 and 7.7+/-6.1%, P<0.01, respectively) compared with normal controls (14.7+/-3.3%), although the mean CBF was not significantly reduced compared with age-matched controls. In the 12 patients with unilateral carotid occlusion, five patients with good collateral flow via the anterior communicating artery showed preserved CVR (11.0+/-7.8%), but those without did not (1.6+/-7.0%). CVR is impaired in alert patients with cerebral infarction, although the mean CBF is not reduced, and good collateral flow via the anterior communicating artery in patients with carotid occlusion may be a sign of well-preserved haemodynamic status.

Ipsilateral pedicle vascularized fibula grafts for reconstruction of tibial defects and non-unions

Between October 1983 and August 1998, 31 patients with non-union or bone defect of the tibia have undergone 32 vascularized fibula transfers to reconstruct lower legs. Of these 32 vascularized fibula transfers, there were 19 pedicle transfers from the ipsilateral leg. There were 17 males and two females. The average patient age was 53 (21 to 84) years old. All patients achieved good bone reconstruction. All patients are currently able to walk without a brace, except for one. As to major complications, three of these 19 had delayed union, with only one postoperative fracture. In the cases with delayed union or fractured grafted fibulas, the periods to walking without a brace were longer than in the cases without such major complications. From the results, the ipsilateral pedicle vascularized fibula graft appears to be a useful option for reconstruction of tibial defects.

[Surgical reconstruction for radiation-induced extracranial vertebral artery stenosis: a case report]

We report a case of symptomatic extracranial vertebral artery stenosis after radiation therapy. This 49-year-old female received radiation therapy to the neck for nasopharyngeal carcinoma 11 years earlier, was admitted because of continuous dizziness and a floating sensation. Magnetic resonanse imaging showed no abnormalities, but an aortography demonstrated complete occlusion of the right common carotid artery as well as occlusion of the right vertebral artery and severe stenosis of the left vertebral artery at its origin, which was presumed to be the result of previous radiation therapy. Percutaneous transluminal angioplasty (PTA) for the left vertebral artery was performed using conventional balloon treatment, which resulted in wall dissection. Because of this, she underwent end-to-side vertebral artery to subclavian artery transposition, and she has had no further ischemic events science that time. PTA has been successfully performed as the first treatment of choice for vertebral artery stenosis, but surgical reconstruction can be a therapeutic management of choice for cases of failed PTA.

[Successful treatment of a patient with low pressure syndrome associated with gait disturbance]

The authors report an unusual case of low intracranial pressure (ICP) syndrome that was successfully treated by the placement of an anti-siphon device (ASD). This 36-year-old male had suffered suprasellar germinoma with hydrocephalus and had had a V-P shunt following radiotherapy. Sixteen years later he developed gait disturbance and somnolence and MRI demonstrated a small lateral ventricle as well as a diffuse dural enhancement. A lumbar tap revealed a low ICP of 12 mmH2O. Because of this, an ASD was placed in the patient. Postoperatively, his symptoms of gait and consciousness disturbance improved. Typical clinical findings of low ICP syndrome such as headache were not observed in this case. To our knowledge, no symptom of gait disturbance with low ICP has been reported previously. We present an interesting case of low ICP syndrome with gait disturbance and discuss the mechanism of the symptoms. Symptoms of this patient were due at first to brain ischemia. After convulsion and consciousness disturbance due to low intracranial pressure, the symptoms increased in strength until gait disturbance occurred. The possibility is suggested that gait disturbance in this patient was due both to brain ischemia and low intracranial pressure.

Crush and imprint cytology of subependymoma: a case report

BACKGROUND

There are few descriptions of the cytologic features of subependymoma because this neoplasm is rare and most commonly encountered incidentally at autopsy. Here we report a surgical case of subependymoma occurring in the lateral ventricle and provide the first documentation of the crush cytologic features of this tumor.

CASE

A 34-year-old woman was found to have a tumorous lesion in the right lateral ventricle. At surgery, a 2-cm-diameter tumor was detected in the anterior horn. Histologic examination during surgery revealed that the mass was composed of loose,fibrillary networks and clusters of nuclei showing mild pleomorphism. A number of microcystic formations were evident. Histologically, the neoplasm was considered benign--specifically, a subependymoma. Papanicolaou- or Giemsa-stained crush specimens and imprint smears were also prepared. The cytologic morphology was fundamentally the same as the histologic. In the crush specimens, microcystic formations were readily visible. Moreover, details of the cellular morphology were more easily recognized in the cytologic slides than in the frozen sections.

CONCLUSION

Cytologic examination, particularly crush cytology, appears to be useful for the rapid diagnosis of subependymoma during surgery in combination with the examination of frozen histologic sections.

Connection designs of three different implant systems in the resorbed edentulous maxilla: a case report

This report presents the mixed use of three different system implants for an implant-supported fixed bridge in a resorbed maxilla. Two of six implants that had been placed were lost. New implants were combined with the remaining implants that had been placed by the previous dentists in 1992 and 1997. The three implant systems consisted of the following: one incorporated an intramobile element into an implant device, and the other two were whole titanium screw-type implants (one with a machined surface and the other with a plasma-sprayed surface). This clinical report describes the connection designs of these different system implants to the fixed bridge and lists the complications that followed.

[Spontaneous dissection of the anterior cerebral artery presenting subarachnoid hemorrhage and cerebral infarction: a case report]

A case is reported of anterior cerebral artery dissecting aneurysm presenting with subarachnoid hemorrhage and cerebral infarction. A 50-year-old man presented with sudden onset of weakness of the left lower limb was admitted to our hospital. CT scan on admission showed a subarachnoid hemorrhage in the interhemispheric fissure and CT on the 6th day demonstrated a cerebral infarction on the right medial frontal lobe. A carotid angiogram 12 hours after the onset showed no aneurysmal lesion, but, the angiogram repeated 11 days after the onset revealed an aneurysmal dilatation with distal narrowing at the right A2-A3 segment. To prevent rebleeding, we performed a wrapping procedure through the interhemispheric route on the 18th day after onset. The postoperative course was uneventful. We reviewed 27 previously reported cases with symptomatic dissecting aneurysm confined to the anterior cerebral artery.

Analysis by enzyme-linked immunosorbent assay and 2-dimensional electrophoresis of haptoglobin in the high-density lipoprotein fraction in cows

Haptoglobin (Hp) is a hemoglobin (Hb)-binding acute-phase protein. Besides its relevance in inflammation, Hp is involved in the regulation of lipid metabolism. In cattle, in addition to the lipoprotein-deficient fraction, Hp is distributed in high-density lipoprotein (HDL) and very high-density lipoprotein (VHDL) fractions. The purpose of this study was to determine Hp concentrations in the lipoprotein fractions using an enzyme-linked immunosorbent assay (ELISA) based on the affinity with Hb, and also to detect structural differences of HDL Hp from that in the lipoprotein-deficient fraction using 2-dimensional electrophoresis. When purified Hp was used as the antigen for the ELISA, the detection limit was 7.4 ng/ml and linearity was obtained from 14.8 to 475 ng/ml. The correlation coefficient between the ELISA and single radial immunodiffusion was 0.884. The ELISA was shown to be applicable to evaluate Hp concentrations in the lipoprotein fractions. Hp concentrations in the lipoprotein fractions were in the range of 0.94 to 8.77 microg of Hp/ml (n = 4), and concentration ratios were 0.2 to 0.3% of whole serum Hp. Of the lipoprotein fractions, Hp was most abundant in HDL, moderate in VHDL and faint in chylomicrons, the very low-density lipoprotein fraction and low-density lipoprotein fraction. By 2-dimensional electrophoresis, alpha- and beta-chains of serum Hp were each separated into 5 spots, and their isoelectric point (pI) values were from 5.05 to 6.28 in the alpha-chain and from 5.92 to 6.95 in the beta-chain. The pI values of HDL Hp were indistinguishable from those of serum Hp. These results indicate that the ELISA based on the affinity with Hb is useful for evaluating Hp concentrations in lipoprotein fractions, and also suggest that HDL Hp is structurally similar to that in the lipoprotein-deficient fraction.

Regulation of conjunctival goblet cell secretion by Ca(2+)and protein kinase C

Conjunctival goblet cells secrete mucus in response to cholinergic (muscarinic) agonists, but the underlying signaling pathways activated in this tissue are not well understood. Cholinergic agonists usually activate phospholipase C to produce inositol 1,4,5 trisphosphate and diacylglycerol. Inositol 1,4,5 trisphosphate increases the intracellular Ca(2+)concentration ([Ca2(+)](i)) while diacylglycerol activates protein kinase C (PKC). PKC and Ca(2+), either by itself or with calmodulin, activate cellular functions. Goblet cell glycoprotein secretion, our index of mucin secretion, was measured from pieces of rat conjunctiva with an enzyme-linked lectin assay using the lectin Ulex europaeus agglutinin I (UEA-I). UEA-I selectively recognizes high molecular weight glycoproteins secreted by the goblet cells. Increasing the [Ca(+)](i)with the Ca(2+)ionophore ionomycin stimulated glycoprotein secretion from conjunctival goblet cells. Cholinergic agonist-induced secretion was completely blocked by chelation of extracellular Ca(2+)and by the Ca(2+)/calmodulin-dependent protein kinase inhibitors KN93 and W7 as well as their inactive analogs KN92 and W5. Activation of classical and novel PKC isozymes by phorbol 12-myristate 13-acetate and phorbol 12,13-dibutyrate stimulated goblet cell glycoprotein secretion. When ionomycin and PMA were added simultaneously, secretion was additive. PKC isozymes were identified by Western blotting analyses with antibodies specific to nine of the 11 PKC isozymes (PKCgamma and zeta were not tested). All nine PKC isozymes were identified in the conjunctival epithelium. The cellular location of the PKC isozymes was determined by immunofluorescence microscopy. Goblet cells contained the classical PKC isozymes PKCalpha, -betaI and -betaII, the novel PKC isozymes PKCepsilon, -theta;, and - mu, and the atypical PKC isozyme PKCzeta. We were unable to determine if PKC activation is required for cholinergic-agonist induced secretion because the PKC inhibitors chelerythrine and staurosporine alone greatly increased secretion. We conclude that Ca(2+)plays a major role in cholinergic agonist-induced conjunctival goblet cell secretion, but this agonist appears not to use Ca(2+)/calmodulin-dependent protein kinases. We also conclude that activated PKC can stimulate goblet cell secretion and that seven different PKC isoforms are present in the goblet cells.

Sequences of cytotoxic T-lymphocyte epitopes in the Epstein-Barr virus (EBV) nuclear antigen-3B gene in a Japanese population with or without EBV-positive lymphoid malignancies

Latent infection antigens of EBV, including EBV nuclear antigens (EBNAs) and latent membrane proteins, are expressed in latently infected and immortalized B cells but work as target antigens for host cytotoxic T-lymphocyte (CTL) responses in an HLA class I-restricted manner. Among these latent antigens, the immunodominant CTL epitopes in EBNA3B (EBNA3B 399-408 and EBNA3B 416-424) are well characterized. Mutations and strain differences in these sequences, compared to the prototype A sequence, reduce CTL responses to latently infected B cells. These EBNA3B CTL epitopes in the normal Japanese population and in 2 lymphoid neoplasias, pyothorax-associated lymphoma (PAL) and nasal natural killer-cell lymphoma, were directly sequenced by PCR. Most EBV in peripheral blood leukocytes (PBLs) from healthy Japanese donors exhibited the prototype A sequence, with mutations in approximately 20% (3/16). The sequence of EBNA3B CTL epitopes in lymphoma tissue was obtained in 6 PAL cases, and 5 exhibited mutations or strain differences compared to the prototype A sequence. Furthermore, the EBNA3B sequence in PAL tissue was different from that in PBLs of the same patient or 1 of the sequences found in PBLs. However, the EBNA3B gene in nasal lymphoma tissues exhibited predominantly the prototype A sequence. Because PAL cells expressed EBNA3B mRNA, detected by RT-PCR, but nasal lymphoma cells did not, mutations and strain differences of the sequences of EBNA3B CTL epitopes were specific findings in EBNA3B-positive lymphomas.

Haemophilus influenzae infection and Guillain-Barré syndrome

It has been reported recently that Haemophilus influenzae can elicit an axonal form of Guillain-Barré syndrome. To investigate the incidence and features of H. influenzae-related Guillain-Barré syndrome, anti-H. influenzae antibody titres were measured by enzyme-linked immunosorbent assay (ELISA) in 46 consecutive Japanese patients with Guillain-Barré syndrome, 49 normal controls, 24 patients with multiple sclerosis and 27 patients with amyotrophic lateral sclerosis (ALS). Whole bacteria of non-encapsulated (non-typable) H. influenzae isolated from one of the Guillain-Barré syndrome patients was the antigen used. Elevated anti-H. influenzae antibodies for two or three classes of IgG, IgM and IgA were found in six (13%) Guillain-Barré syndrome patients, but not in the normal controls and patients with multiple sclerosis or ALS. The incidence was significantly higher in patients with Guillain-Barré syndrome than in the normal controls (P = 0.01) and patients with multiple sclerosis or ALS (P = 0.009). Western blot analysis confirmed that the H. influenzae-positive patients' IgG recognized the lipopolysaccharides of H. influenzae. Guillain-Barré syndrome patients with anti-H. influenzae antibodies showed relatively uniform clinical and laboratory features: prodromal respiratory infection, less frequent cranial and sensory nerve involvement, pure motor axonal degeneration on electrophysiology, and positivity for IgG anti-GM1 antibodies. Although the features were similar to those in Guillain-Barré syndrome patients infected by Campylobacter jejuni, the recoveries seemed to be better in patients with H. influenzae-related Guillain-Barré syndrome. It is concluded that a form of Guillain-Barré syndrome occurs after respiratory infection by H. influenzae in the Japanese population. A particular strain of non-typable H. influenzae has a ganglioside GM1-like structure and elicits axonal Guillain-Barré syndrome similar to C. jejuni-related Guillain-Barré syndrome.

[5'-DFUR chemoprophylaxis in superficial bladder cancer. Kanagawa Urology 5'-DFUR Study Group]

5'-Deoxy-5-fluorouridine (5'-DFUR), an oral fluorinated pyrimidine carbamate, is widely used in patients with gastrointestinal and breast cancers because of its effectiveness. However, in bladder cancer, response rates have only been reported in Phase II clinical trials. Therefore, we conducted a prospective randomized trial to investigate chemoprophylactic effect of 5'-DFUR against recurrence of superficial bladder cancer after transurethral bladder tumor resection (TUR-Bt). The subjects were grouped as follows: 1) 5'-DFUR group (n = 31), received 600 mg/day of 5'-DFUR starting 2-3 weeks after TUR-Bt for 2 years; and 2) control group (n = 31) received no 5'-DFUR. Although there was no significant difference between groups, the cumulative recurrence rates was more favorable in the 5'-DFUR group (p = 0.256) than in the controls. Results according to cancer factors showed that, in patients with G2 based on grading, those in the 5'-DFUR group tended to have a lower recurrence rate than the control group (p = 0.070). There was a 40% incidence of adverse drug reactions (12/30 patients), primarily slight gastrointestinal symptoms which disappeared or improved with drug discontinuation. The results of the present study suggest that 5'-DFUR might be the choice of treatment to prevent recurrence of superficial bladder cancer.

Low frequency of HLA-A*0201 allele in patients with Epstein-Barr virus-positive nasal lymphomas with polymorphic reticulosis morphology

Lymphoproliferative diseases of the nasal cavity and paranasal sinuses occur frequently in Asian countries and are histologically categorized as monomorphic ordinary lymphoma and polymorphic reticulosis (PR) with apparent inflammatory cell infiltration. The large atypical cells in PR show natural-killer cell nature and frequently contain Epstein-Barr virus (EBV) DNA. Among the EBV genes involved in latent infection, those encoding EBV latent membrane proteins are frequently expressed in PR. Several cytotoxic T-lymphocyte (CTL) defined epitopes have been mapped to latent membrane proteins restricted with HLA-A2, -A11 or -A24 antigens. Thus, the HLA-A allele may affect the development of PR. To examine this possibility, HLA-A alleles of 25 patients with EBV(+) PR were determined with low-resolution polymerase chain reaction-based typing using HLA-A locus sequence-specific primer combinations. The frequency of HLA-A alleles including HLA-A2 and -A24 antigens in PR patients was lower than that in the normal Japanese population, but the difference was not significant. Since HLA-A2-restricted CTL responses are well delineated at the A2-subtype level, the A2-subtype of PR cases with HLA-A2 antigen was further determined by high-resolution genetic typing. The frequency of HLA-A*0201 in PR was significantly lower than in the normal population (p=0.0314). The HLA-A*0201-restricted CTL responses may thus function in vivo to suppress the development of overt lymphoma.

Pyruvate secreted by human lymphoid cell lines protects cells from hydrogen peroxide mediated cell death

Reactive oxygen species (ROS) released from polymorphonuclear leukocytes and macrophages could cause DNA damage, but also induce cell death. Therefore inhibition of cell death must be an important issue for accumulation of genetic changes in lymphoid cells in inflammatory foci. Scavengers in the post culture medium of four lymphoid cell lines, lymphoblastoid cell lines (LCL), Raji, BJAB and Jurkat cells, were examined. Over 80% of cultured cells showed cell death 24 h after xanthine (X)/xanthine oxidase (XOD) treatment, which was suppressed by addition of post culture medium from four cell lines in a dose-dependent manner. H2O2 but not O2*- produced by the X/XOD reaction was responsible for the cytotoxity, thus we used H2O2 as ROS stress thereafter. The H2O2-scavenging activity of post culture media from four cell lines increased rapidly at the first day and continued to increase in the following 2-3 days for LCL, Raji and BJAB cells. The scavenging substance was shown to be pyruvate, with various concentrations in the cultured medium among cell lines. Over 99% of total pyruvate was present in the extracellular media and less than 1% in cells. alpha-Cyano-4-hydroxycinnamate, a specific inhibitor of the H+-monocarbohydrate transporter, increased the H2O2-scavenging activity in the media from all four cell lines via inhibition of pyruvate re-uptake by cultured cells from the media. These findings suggest that lymphoid cells in inflammatory foci could survive even under ROS by producing pyruvate, so that accumulation of lymphoid cells with DNA damage is possible.

[Von Hippel-Lindau disease]

The von Hippel-Lindau (VHL) disease is a multitumor syndrome characterized by CNS hemangioblastoma, pheochromocytoma and renal cell carcinoma. The VHL disease gene is a putative tumor suppressor gene responsible for VHL disease. VHL disease without pheochromocytoma (pheo) and those with pheo are classified as type 1 or type 2, respectively. Germline missense mutations are clustered in 4 regions in the VHL gene. The VHL protein is now regarded as a one of the key protein for ubiquitination and further degradation of certain transcription factors such as hypoxia inducible factor (HIF). Since almost of germline mutations are detectable, presymptomatic diagnosis of the VHL disease with DNA analyses is important to improve the prognosis of VHL disease.

Role of the von Hippel-Lindau tumor suppressor protein during neuronal differentiation

The von Hippel-Lindau (VHL) tumor suppressor protein down-regulates transcription by transcriptional elongation enhanced by antagonizing elongin B and C. Transcriptional regulation is an important control mechanism for embryogenesis and tumorigenesis. The VHL gene and protein are expressed in neuronal cells of the fetal and adult brain. However, the role of the VHL gene in the central nervous system (CNS) has not been elucidated. The VHL gene might modify the expression of various genes during embryogenesis and tumorigenesis in CNS. We investigated the role of the VHL gene in CNS development using rodent CNS progenitor cells. Here we show that expression of the VHL protein is correlated with neuronal differentiation but not with glial differentiation in CNS progenitor cells, and we also show that VHL gene transduction induces neuronal differentiation. In addition, a VHL mRNA antisense oligonucleotide inhibits differentiation of CNS progenitor cells and up-regulates their cell cycle. In conclusion, the VHL gene plays an essential role in neuronal differentiation as well as transcription.

Effects of cyclic polylactate (CPL) on the growth of cloned leukemic cells in vitro

A novel supramolecular oligomer, cyclic polylactate (CPL), was first discovered in the culture medium of HeLa-S tumour cells, and was reported to inhibit the growth of FM3A ascites tumour cells by inhibiting the activities of pyruvate kinase (PK) and lactic dehydrogenase (LDH). We have now synthesized CPL-containing oligomers with polymerization numbers ranging from 9 to 19, by prolonged heating and rapid mixing of a carbohydrate compound of the L-lactic acid monomer (C(3)H(6)O(3)) under decreased pressure and have studied its effects on the growth of leukemic cells. Treatment with 0.02 mg/ml CPL inhibited the growth of HL60 and TF-1 cells, while the growth of K562 cells was inhibited by 0.2 mg/ml CPL. A concentration of 2 mg/ml CPL was required to inhibit granulocyte-macrophage progenitor cell (CFU-GM) and burst-forming unit erythroid (BFU-E) precursor colony formation among normal bone marrow cells. Furthermore, 7A6 antigen expression and DNA ladder formation were observed in leukemic cells cultured with CPL, indicating that CPL induces apoptotic changes in these cells. These findings suggest that CPL might be a useful chemotherapeutic agent for leukemia.

Molecular cloning and expression profile of rat myocilin

Myocilin is known to be associated with the pathogenesis of juvenile-onset primary open angle glaucoma. The tissue distribution of myocilin transcripts has been analyzed in both humans and mice, and a high level of expression in the retina and skeletal muscle has been reported. The functions of myocilin in these tissues are unknown. We isolated rat myocilin cDNA and examined the expression pattern of myocilin, including its expression in endocrine organs, using Northern blot analysis. The rat myocilin cDNA sequence has two in-frame initiation codons, the upstream and downstream ATGs corresponding to the initiation codon of human and murine myocilin, respectively. It is most likely that the first ATG is a translational initiation codon, since 8 of 13 amino acid residues deduced from the rat cDNA sequence between the first and the second ATGs are the same as those in human myocilin. The open reading frame encodes 502 amino acids. Rat myocilin also has both a myosin-like domain and an olfactmedin-like domain, which have been identified in human and murine myocilin. Northern analysis of rat myocilin mRNA revealed substantial expression in the thyroid gland, as well as in the retina and muscle. No transcripts were detected in other endocrine glands, including the adrenal gland, pituitary, and testis. Myocilin may play an important role in thyroid function. Further study of the expression and role of myocilin in the thyroid is required.

Induction of chromosomal aberrations and growth-transformation of lymphoblastoid cell lines by inhibition of reactive oxygen species-induced apoptosis with interleukin-6

Etiological evidence, indicating the relationships between the onset of malignant lymphoma and pre-existing chronic inflammation, has been accumulated. For the autonomous growth of malignant tumor, genetic lesions, such as chromosomal aberrations, amplification of oncogenes, and mutations of genes involved in the cell cycle regulation, must be essential. However, how the inflammation promotes the accumulation of genetic lesions and induces the autonomous growth of lymphoid cells remains unclear. Reactive oxygen species released by polymorphonuclear leukocytes and macrophages are factors causing DNA damage in the foci of inflammation, and thus could play a role in lymphomagenesis. The xanthine/xanthine oxidase (X/XOD) system produces a mixture of hydrogen peroxide and superoxide anion extracellularly, and thus serves as an in vitro source of reactive oxygen species. Cell death of lymphoblastoid cell lines (LCLs) was induced with X/XOD treatment in a dose-dependent manner. DNA fragmentation, which is the characteristic feature of apoptosis, was observed in LCLs at 4-8 hours after X/XOD treatment. Among cytokines such as interleukin-6 (IL-6), IL-10, and interferon-gamma, only pretreatment with IL-6 gave LCLs the resistance to X/XOD-induced cell death in a dose-dependent manner. The proportion of apoptotic cells in X/XOD-treated LCL culture was decreased with IL-6 pretreatment by quantification with flow cytometric analysis. Treatment of LCLs with IL-6 for 48 hours up-regulated bcl-2 mRNA expression. Furthermore, the LCLs repeatedly treated with X/XOD and cultured with or without IL-6 showed many more structural abnormalities of chromosomes than those without X/XOD treatment. Colony forming efficiency of X/XOD-treated LCLs with IL-6 was significantly higher than those without IL-6, and even relatively higher than LCLs without X/XOD treatment. IL-6 could support the survival of non-neoplastic B cells and accelerate the malignant transformation of B lineage cells in inflammatory lesions.

In vivo gene gun-mediated DNA delivery into rodent brain tissue

Various types of gene transfer into live tissues have been tried. However, in vivo gene transfer into brain tissue or neuronal cells without virus vector has required a great effort. Particle-mediated gene transfer into live brain tissue was thought to be impossible because of its fragility and the mechanical problem of a previous type of gene gun. In addition, particle-mediated DNA transfer into monolayer-cultured cells without mechanical damage has been difficult. We successfully transferred DNA into rodent live brain tissue and also into monolayer-cultured cells without mechanical damage by using a new type of gene gun and also confirmed gene expression in the brain. This new method represents another variation of gene transfer into the brain.

Analysis of T-cell antigen receptor gamma chain gene rearrangement by polymerase chain reaction in combination with denaturing gradient gel electrophoresis in the differential diagnosis of cutaneous T-lymphoproliferative diseases

A polymerase chain reaction (PCR)-based strategy has been developed for analysis of clonal rearrangement of the T-cell receptor gamma gene (TCR gamma) and was shown to be useful for detection of clonal T-cell populations. In this study, we performed PCR combined with denaturing gradient gel electrophoresis (DGGE) on fresh frozen biopsy samples from 16 patients with cutaneous T-lymphoproliferative diseases in whom a definite diagnosis was difficult to make on morphological and immunohistochemical grounds alone. Ages of the patients at biopsy ranged from 28 to 81 (median 62) years, and the subjects consisted of 8 men and 8 women. They presented with erythema on the extremities in 5 cases, trunk in 7, buttock in 2, and papules on the trunk and face in one case each. Clonal rearrangement of TCR gamma was observed in 3 of 16 cases. Clinical diagnoses of these three cases were mycosis fungoides, cutaneous invasion of adult T-cell leukemia (ATL), and large granular lymphocytic leukemia (LGL) of T-cell type, respectively, but they were histologically difficult to differentiate from reactive cutaneous T-cell proliferation. The skin lesions of the LGL case worsened, and this patient died two years after biopsy. Another patient with suspected mycosis fungoides in the plaque stage died due to dissemination of tumors 22 months after biopsy. The remaining one patient with ATL survived with cutaneous lesions for over four years. Clonality was not demonstrated in the remaining 13 cases, and their clinical courses were favorable. These findings showed that demonstration of clonal TCR gamma gene rearrangement using the PCR-DGGE method is very helpful for diagnosis of cutaneous T-cell neoplasms.

Expressions of Fas ligand and other apoptosis-related genes and their prognostic significance in epithelial ovarian neoplasms

Expression of apoptosis-related proteins, bcl-2, Bax, Fas and Fas ligand (L), in ovarian epithelial neoplasms together with its clinical relevance was examined by immunohistochemistry. They included 36 cases with adenoma, 33 with low potential malignancy (LPM) and 63 with carcinomas. bcl-2 expression was observed in 14 of 36 cases (39%) with adenoma, five of 33 (15%) with LPM (P< 0.05) and 12 of 63 (19%) with carcinoma (P < 0.05). Cases with bcl-2 expression showed more favourable prognosis than those without, but the difference was not statistically significant. There was no difference in frequency of Bax and Fas expression between each histologic category. Fas L expression was observed in one of 36 cases (3%) with adenoma, but in 12 of 33 (36%) with LPM (P < 0.001) and 42 of 63 (67%) with carcinoma (P < 0.0001). In carcinomas, cases expressing Fas L showed a less favourable prognosis than those without (P = 0.02). Density of CD8+ lymphocytes, possibly cytotoxic T-cells, was higher in serous carcinoma with negative Fas L expression than those with positive Fas L expression. These findings suggest that Fas L expressing carcinomas induce apoptosis in infiltrating CTL with Fas expression, and escape from immune surveillance.

Hexokinase: gene structure and mutations

Hexokinase (HK) deficiency is a rare red cell enzyme deficiency associated with hereditary non-spherocytic haemolytic anaemia; to date, only 17 affected families have been reported. Human HK has four major isozymes, each of which is encoded by a separate gene. Recent studies have shown that both ubiquitously expressed type I HK (HK-I) and erythroid-specific HK-R are expressed in erythrocytes, and that these isozymes are encoded by the single HK-I gene. The human HK-I gene has 19 exons, the HK-I and HK-R transcripts being produced by using two distinct promoters. Thus, the first and second exons are specifically utilized for the erythroid-specific HK-R and ubiquitously expressed HK-I isozymes respectively. So far, only two HK variants have been analysed at the molecular level. Since the human HK-I crystal structure has recently been elucidated, the molecular analysis of the HK variants will be useful for discussing the structure-function relationship of the enzyme.