TAD boundary deletion causes PITX2-related cardiac electrical and structural defects

While 3D chromatin organization in topologically associating domains (TADs) and loops mediating regulatory element-promoter interactions is crucial for tissue-specific gene regulation, the extent of their involvement in human Mendelian disease is largely unknown. Here, we identify 7 families presenting a new cardiac entity associated with a heterozygous deletion of 2 CTCF binding sites on 4q25, inducing TAD fusion and chromatin conformation remodeling. The CTCF binding sites are located in a gene desert at 1 Mb from the Paired-like homeodomain transcription factor 2 gene (PITX2). By introducing the ortholog of the human deletion in the mouse genome, we recapitulate the patient phenotype and characterize an opposite dysregulation of PITX2 expression in the sinoatrial node (ectopic activation) and ventricle (reduction), respectively. Chromatin conformation assay performed in human induced pluripotent stem cell-derived cardiomyocytes harboring the minimal deletion identified in family#1 reveals a conformation remodeling and fusion of TADs. We conclude that TAD remodeling mediated by deletion of CTCF binding sites causes a new autosomal dominant Mendelian cardiac disorder.

Quality of life after total pancreatectomy with islet autotransplantation for chronic pancreatitis in Japan

BACKGROUND

Patients with chronic pancreatitis (CP) often have severe and intractable abdominal pain, leading to decreased quality of life (QOL), inability to work or attend school, and increased health care costs due to repeated emergency room visits and hospitalizations.

METHODS

We evaluated the efficacy of total pancreatectomy and islet autotransplantation (TPIAT) in terms of pain control and QOL in CP patients treated at our center in Japan. To evaluate QOL, we used the Short-Form 36 Health Survey version 2 (SF-36v2_® Standard, Japanese), European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30), and Quality of Life Questionnaire-Pancreatic Modification (QLQ-PAN28).

RESULTS

Between August 2016 and June 2019, we performed this procedure in 5 patients. All patients were followed up for 12 months and all transplanted islets were still functioning at the 1-year follow-up. The major adverse events were abdominal wall hemorrhage, intestinal obstruction, intra-abdominal abscess, and abdominal pain requiring hospitalization; no case had sequelae. No major complications were due to islet transplantation. Pain scores improved postoperatively in all patients. Three QOL item dimensions role-physical (p = 0.03125), general health perception (p = 0.03125) and vitality (p = 0.03125) in the SF-36 were significantly improved 12 months after TPIAT. Mean values of many other QOL items improved, though not significantly.

CONCLUSION

The QOL improvement after TPIAT for CP suggests its effectiveness in the Japanese population.

Graft failure after allogeneic islet transplantation in a patient with type 1 diabetes and a high anti-glutamic acid decarboxylase antibody titer

Pancreatic islet transplantation is a β-cell replacement therapy for people with insulin-deficient diabetes who have difficulty in glycemic control and suffer from frequent severe hypoglycemia. However, the number of islet transplantations carried out is still limited in Asia. We report a case of allogeneic islet transplantation in a 45-year-old Japanese man with type 1 diabetes. Although the islet transplantation was successfully carried out, graft loss was observed on the 18th day. Immunosuppressants were used in accordance with the protocol, and donor-specific anti-human leukocyte antigen antibodies were not detected. Autoimmunity relapse was also not observed. However, the patient had a high titer of anti-glutamic acid decarboxylase antibody from before the islet transplantation, and autoimmunity might thus have affected the β-cells in the transplanted islet. The evidence is still scarce to reach conclusions, and further data accumulation is required to enable proper patient selection before islet transplantation.

A porcine islet-encapsulation device that enables long-term discordant xenotransplantation in immunocompetent diabetic mice

Islet transplantation is an effective treatment for type 1 diabetes (T1D). However, a shortage of donors and the need for immunosuppressants are major issues. The ideal solution is to develop a source of insulin-secreting cells and an immunoprotective method. No bioartificial pancreas (BAP) devices currently meet all of the functions of long-term glycemic control, islet survival, immunoprotection, discordant xenotransplantation feasibility, and biocompatibility. We developed a device in which porcine islets were encapsulated in a highly stable and permeable hydrogel and a biocompatible immunoisolation membrane. Discordant xenotransplantation of the device into diabetic mice improved glycemic control for more than 200 days. Glycemic control was also improved in new diabetic mice "relay-transplanted" with the device after its retrieval. The easily retrieved devices exhibited almost no adhesion or fibrosis and showed sustained insulin secretion even after the two xenotransplantations. This device has the potential to be a useful BAP for T1D.

Pancreatic islet transplantation: toward definitive treatment for diabetes mellitus

Since the late 20th century, advances in pancreatic islet transplantation have targeted improved glycemic control and fewer hypoglycemic events in patients with type 1 diabetes, and some important milestones have been reached. Following the Edmonton group's success in achieving insulin independence in all transplanted patients with type 1 diabetes, clinical islet transplantation is now performed worldwide. β cell replacement therapy for type 1 diabetes was established based on the favorable outcomes of a phase 3, prospective, open-label, single-arm, clinical study conducted at 8 centers in North America, in which 42 of 48 patients who underwent islet transplantation from 2008 to 2011 achieved HbA1c < 7.0% (53 mmol/mol) at day 365, which was maintained at 2 years in 34 patients. In Japan, a phase 2 multicenter clinical trial of islet transplantation for type 1 diabetes patients is currently ongoing and will end soon, but the interim results have already led to positive changes, with allogeneic islet transplantation being covered by the national health insurance system since April 2020. Current efforts are being made to solve the problem of donor shortage by studying alternative donor sources, such as porcine islets and pancreatic progenitor cells derived from pluripotent stem cells. The results of clinical trials in this area are eagerly awaited. It is hoped that they will contribute to establishing alternative sources for insulin-producing β cells in the near future.

Enhanced engraftment, proliferation, and therapeutic potential in heart using optimized human iPSC-derived cardiomyocytes

Human pluripotent stem cell-derived cardiomyocytes (CMs) are a promising tool for cardiac cell therapy. Although transplantation of induced pluripotent stem cell (iPSC)-derived CMs have been reported in several animal models, the treatment effect was limited, probably due to poor optimization of the injected cells. To optimize graft cells for cardiac reconstruction, we compared the engraftment efficiency of intramyocardially-injected undifferentiated-iPSCs, day 4 mesodermal cells, and day 8, day 20, and day 30 purified iPSC-CMs after initial differentiation by tracing the engraftment ratio (ER) using in vivo bioluminescence imaging. This analysis revealed the ER of day 20 CMs was significantly higher compared to other cells. Transplantation of day 20 CMs into the infarcted hearts of immunodeficient mice showed good engraftment, and echocardiography showed significant functional improvement by cell therapy. Moreover, the imaging signal and ratio of Ki67-positive CMs at 3 months post injection indicated engrafted CMs proliferated in the host heart. Although this graft growth reached a plateau at 3 months, histological analysis confirmed progressive maturation from 3 to 6 months. These results suggested that day 20 CMs had very high engraftment, proliferation, and therapeutic potential in host mouse hearts. They also demonstrate this model can be used to track the fate of transplanted cells over a long time.

Efficient Detection and Purification of Cell Populations Using Synthetic MicroRNA Switches

Isolation of specific cell types, including pluripotent stem cell (PSC)-derived populations, is frequently accomplished using cell surface antigens expressed by the cells of interest. However, specific antigens for many cell types have not been identified, making their isolation difficult. Here, we describe an efficient method for purifying cells based on endogenous miRNA activity. We designed synthetic mRNAs encoding a fluorescent protein tagged with sequences targeted by miRNAs expressed by the cells of interest. These miRNA switches control their translation levels by sensing miRNA activities. Several miRNA switches (miR-1-, miR-208a-, and miR-499a-5p-switches) efficiently purified cardiomyocytes differentiated from human PSCs, and switches encoding the apoptosis inducer Bim enriched for cardiomyocytes without cell sorting. This approach is generally applicable, as miR-126-, miR-122-5p-, and miR-375-switches purified endothelial cells, hepatocytes, and insulin-producing cells differentiated from hPSCs, respectively. Thus, miRNA switches can purify cell populations for which other isolation strategies are unavailable.

Actinobacillus actinomycetemcomitans lipopolysaccharide stimulates collagen phagocytosis by human gingival fibroblasts

INTRODUCTION

Collagen phagocytosis by fibroblasts is involved in the intracellular pathway related to collagen breakdown in soft connective tissues. The possible role of lipopolysaccharide (LPS) in regulating this fibroblast function has not been elucidated so we investigated the effect of LPS from Actinobacillus actinomycetemcomitans, a periodontopathic bacterium, on collagen phagocytic activity in human gingival fibroblasts and associated regulatory mechanisms.

METHODS

LPS pretreatment stimulated binding of collagen-coated beads to cells and, subsequently, their internalization.

RESULTS

The LPS-activated collagen phagocytic process was enhanced in the presence of the soluble form of CD14 (sCD14) or LPS-binding protein (LBP), while the LPS/LBP treatment activated Akt and induced actin reorganization. Furthermore, these LPS/LBP-induced effects were partially suppressed by adding phosphatidyl-inositol-3 kinase (PI3K) inhibitors.

CONCLUSION

These results suggest that A. actinomycetemcomitans LPS disturbs the homeostasis of collagen metabolism within gingival tissue by facilitating collagen phagocytosis by gingival fibroblasts, and serum sCD14 and LBP positively regulate the action of LPS. In addition, the PI3K/Akt signaling is thought to partially mediate the LPS/LBP-stimulated collagen phagocytic pathway, which may be dependent on actin cytoskeletal rearrangement.

Vitamin K therapy for cortical bone fragility caused by reduced mechanical loading in a child with hemiplegia

Fractures frequently occur at cortical bone sites in children with cerebral palsy, but there is no established therapy. We previously found that treatment with vitamins D and K increased cortical bone mass in children with severe physical disability, and have hypothesized that vitamin K could play a significant role in pediatric cortical bones under conditions with reduced mechanical loading. In the present case report, we treated a right hemiplegic ambulant eight-year-old boy with oral vitamin K (15 mg per day) for eight months. Cortical bone geometries at mid-diaphyseal sites in bilateral tibiae were evaluated before and after the treatment. The cross-sectional total, bone and marrow areas of non-hemiplegic tibia increased by 8.8%, 7.4% and 12.0%, respectively, while those of hemiplegic tibia changed by 9.0%, 14.9% and -3.4%, respectively. As a result, the polar moment of inertia, an indicator of the resistance to torsion forces, increased by 13.0% in the non-hemiplegic tibia and by 63.7% in the hemiplegic tibia. Vitamin K may restrict cortical bone fragility, caused by reduced mechanical loading, through its actions at the endosteal bone marrow interface. Further studies are needed to confirm these findings and to clarify the mechanisms involved.

Treatment of autoimmune diseases in MRL/lpr mice by allogenic bone marrow transplantation plus adult thymus transplantation

MRL/lpr mice (H-2(k)) with Fas gene mutation develop severe autoimmune diseases, and their haematolymphoid cells such as bone marrow and spleen cells showed a low apoptotic activity by irradiation. Therefore, conventional bone marrow transplantation (BMT) cannot be used to treat autoimmune diseases in these mice (chimeric resistance). In the present study, we examine the effects of additional adult thymus transplantation (TT) from the same donor on successful BMT. When the MRL/lpr mice were lethally irradiated (9 x 5Gy) and reconstituted with 3 x 10(7) of C57BL/6 mouse (H-2b) bone marrow cells (BMCs) in conjunction with TT, the mice significantly survived long term and showed a high donor-derived chimerism in comparison with those treated with BMT alone. Interestingly, the numbers of not only donor-derived T cells but also B cells increased significantly in the mice treated with BMT plus TT, even at the early phase of BMT. The number of aberrant CD3+B220+ cells decreased significantly, and the numbers of lymphocyte subsets were also normalized 4 weeks after the treatment. Finally, the autoimmune diseases in MRL/lpr mice could be cured by BMT with TT. These results indicate that the combination of BMT plus TT can overcome the chimeric resistance and treat the autoimmune diseases in MRL/lpr mice.

Interferon-γ inhibits collagen phagocytosis in human fibroblasts by inducing subcortical actin assembly and reducing ability of β1 integrin to bind to collagen

OBJECTIVE

We investigated the possible roles of interferon-gamma (IFN-gamma) in modulation of extracellular and intracellular routes of collagen digestion by human fibroblasts.

METHODS

Human gingival fibroblasts were treated with IFN-gamma, after which matrix metalloproteinase-1 (MMP-1) activation was determined. Following the IFN-gamma treatment, cells were further incubated with either activating antibody for beta1 integrin or actin monomer-sequestering agent latrunculin B before incubation with collagen-coated fluorescent beads. Thereafter, the binding and internalization of the beads were assessed.

RESULTS

IFN-gamma had no significant effect on MMP-1 activation, however, it reduced the binding of collagen-coated beads in the minimum affinity range and, subsequently, internalization of the beads. The inhibitory effects of IFN-gamma were partially reversed by adding either the beta1 integrin activating antibody or latrunculin B.

CONCLUSIONS

Although IFN-gamma does not appreciably moderate the extracellular route of collagen digestion by human fibroblasts, the reduced level of collagen phagocytosis by IFN-gamma in the cells may contribute to fibrosis in inflamed connective tissues. Further, IFN-gamma may decrease the binding of collagen and following phagocytosis in cells by inducing a subcortical actin assembly and reducing the ability of beta1 integrin to bind to collagen.

RB silencing compromises the DNA damage-induced G2/M checkpoint and causes deregulated expression of the ECT2 oncogene

As alterations in retinoblastoma (RB)/E2F pathway are commonly found in human cancers, the molecular mechanism underlying cell cycle deregulation caused by the mutations in the RB/E2F pathway needs to be investigated extensively. Compared with good understanding of RB/E2F functions in G1-S cell cycle progression, it is not fully understood how an abrogated RB pathway affects the G2-M phase of the cell cycle. Here, we report that disruption of RB accelerated G2-M progression in the presence of DNA damage by elevating the expression of a set of mitotic regulatory genes. We generated RB(+)- and (-)-matched cells using short hairpin RNA. In the RB(-) cells, the G2/M checkpoint mediated by a DNA-damaging agent was over-ridden. With microarray analysis, we found that the expression of key G2-M regulatory genes was upregulated in RB(-) cells. In particular, we demonstrated that the proto-oncogene ECT2 was directly regulated by E2Fs. Furthermore, suppression of ECT2 expression by small interfering RNA in RB(-) cells resulted in cytokinesis arrest, suggesting that RB(-) cells lack the regulation of E2F-mediated cytokinesis. These results indicate that aberrant ECT2 expression, observed in various human tumors, could be the direct result of RB/E2F pathway deficiency, thereby contributing to cell division in cancers.

Relationship of p53, Bcl-2, Ki-67 index and E-cadherin expression in early invasive breast cancers with comedonecrosis as an accelerated apoptosis

AIMS

To study the relationship between comedonecrosis formation and morphology, apoptosis, and p53, Bcl-2, Ki-67 index and E-cadherin expression in early invasive breast cancer.

EXPERIMENTAL DESIGN

Early invasive breast cancers were first divided into two groups according to the presence (CN+ tumours) or absence (CN- tumours) of comedonecrosis. The histological grade, apoptosis, and expression of E-cadherin, Ki-67, p53 and Bcl-2 in the cancer-affected area, and in normal ducts from the specimen, were then examined.

RESULTS

Less tubule and gland formation was seen in CN+ tumours than in CN- tumours, although the histological grade between the groups was not different. During early comedonecrosis, cells undergo apoptosis and subsequent necrosis. p53 was higher in CN+ tumours than in CN- tumours and normal ducts, whereas Bcl-2 was lower in CN+ tumours than in CN- tumours and normal ducts. Both tumours had higher Ki-67 than in normal ducts, but no difference was evident between the tumours. CN+ tumours had slightly higher E-cadherin than that in CN- tumours, but lower than that in normal ducts. The level of comedonecrosis was positively correlated with p53, but inversely correlated with Bcl-2 in all tumours, and p53 and Bcl-2 were inversely correlated with each other. Furthermore, comedonecrosis and p53 were correlated with Ki-67 in CN+ tumours, and Bcl-2 was correlated with Ki-67 in CN- tumours.

CONCLUSION

Comedonecrosis may be actively regulated through an apoptotic procedure in massive cancers for their survival and progression, and the above proteins may be associated cooperatively in this process. CN+ and CN- tumours may have opposite proliferative systems under the p53-Bcl-2 pathway.

A novel approach for the development of selective Cdk4 inhibitors: library design based on locations of Cdk4 specific amino acid residues

Identification of a selective inhibitor for a particular protein kinase without inhibition of other kinases is critical for use as a biological tool or drug. However, this is very difficult because there are hundreds of homologous kinases and their kinase domains including the ATP binding pocket have a common folding pattern. To address this issue, we applied the following structure-based approach for designing selective Cdk4 inhibitors: (1) identification of specifically altered amino acid residues around the ATP binding pocket in Cdk4 by comparison of 390 representative kinases, (2) prediction of appropriate positions to introduce substituents in lead compounds based on the locations of the altered amino acid residues and the binding modes of lead compounds, and (3) library design to interact with the altered amino acid residues supported by de novo design programs. Accordingly, Asp99, Thr102, and Gln98 of Cdk4, which are located in the p16 binding region, were selected as first target residues for specific interactions with Cdk4. Subsequently, the 5-position of the pyrazole ring in the pyrazol-3-ylurea class of lead compound (2a) was predicted to be a suitable position to introduce substituents. We then designed a chemical library of pyrazol-3-ylurea substituted with alkylaminomethyl groups based on the output structures of de novo design programs. Thus we identified a highly selective and potent Cdk4 inhibitor, 15b, substituted with a 5-chloroindan-2-ylaminomethyl group. Compound 15b showed higher selectivity on Cdk4 over those on not only Cdk1/2 (780-fold/190-fold) but also many other kinases (>430-fold) that have been tested thus far. The structural basis for Cdk4 selective inhibition by 15b was analyzed by combining molecular modeling and the X-ray analysis of the Cdk4 mimic Cdk2-inhibitor complex. The results suggest that the hydrogen bond with the carboxyl group of Asp99 and hydrophobic van der Waals contact with the side chains of Thr102 and Gln98 are important. Compound 15b was found to cause cell cycle arrest of the Rb(+) cancer cell line in the G(1) phase, indicating that it is a good biological tool.

92nd Annual Meeting of the American Association for Cancer Research. 24-28 March, 2001, New Orleans, Louisiana, USA

The 92nd Annual Meeting of the AACR comprised over 5000 abstracts, 12 plenary and award lectures and numerous talks in educational sessions, symposia and mini-symposia. Given the wealth of information presented, we narrowed our coverage to the area of prenyltransferase and protein kinase inhibitors. Many rationally designed drugs are now in clinical trials and exciting results were presented for the Bcr-Abl inhibitor STI-571. The cancer community is beginning to envision new ways to evaluate and administer these well-tolerated drugs which do not fit the traditional anticancer drug profile. There is an emphasis in developing surrogate markers for evaluating the mechanism-based effectiveness as well as identifying off-target toxicities. In addition, there is a large effort in investigating effective drug combinations and the use of these new agents as radiosensitisers. Here we present specific examples of these issues as applied to prenylation and protein kinase inhibitors.

Clinicostatistical study of ameloblastoma treatment

The purpose of this study was to investigate the treatment of 190 cases of ameloblastoma in our department from 1966 to 1994. The statistical results with regard to age, sex and region agreed with those of other investigators. Thirty-five of 43 (81.4%) cases underwent enucleation in 1960s, but the sixteen of 27 (59.3%) cases underwent partial resection of mandible in 1990s. The defect of mandible was reconstructed with iliac bone grafting since 1968, grafts with a mixture of iliac blocked bone and PCBM (particulate cancellous bone and marrow) have been used since 1975. Grafting of the inferior alveolar nerve with the great auricular nerve to the defect has been performed in our department since 1977. Recently, technique involving pull-through of the inferior alveolar nerve bundle has been used in our department. When the reconstruction method for the mandible and nerve has been established, it becomes possible to operate radically and positively. Recurrence occurred in 17 cases after the primary enucleation. It is thought that the primary treatment of ameloblastoma must be as radical as possible. It appears to be necessary to observe progress and perform follow-up in cases of ameloblastoma for more than ten years, because there was one recurrence at 9 years and 4 months after the first operation. In fact, three quarters of our cases were lost to follow-up. Such losses can problems in confirming recurrence and responding rapidly.

Malonate decarboxylase of Pseudomonas putida is composed of five subunits

Two different forms of malonate decarboxylase were purified from Pseudomonas putida. The active form was composed of the five different subunits alpha (60 kDa), beta (33 kDa), gamma (28 kDa), delta (13 kDa), and epsilon (30 kDa) and the inactive form was composed of the four subunits lacking the epsilon subunit. The former catalyzed the decarboxylation of malonate to acetate, but the latter could not, although it retained both activities of acetyl-CoA:malonate CoA transferase and malonyl-CoA decarboxylase. The delta subunit of the active form was acylated by the incubation with [2-14C]malonyl-CoA, but the delta subunit of the inactive form was not labeled. From the above results and the N-terminal amino acid sequence analysis, it was concluded that the epsilon subunit was an essential subunit to function as malonyl-CoA:ACP transacylase, which was an indispensable component of the enzyme for the cyclic decarboxylation of malonate.

Site-directed mutational analysis for the ATP binding of DnaA protein. Functions of two conserved amino acids (Lys-178 and Asp-235) located in the ATP-binding domain of DnaA protein in vitro and in vivo

DnaA protein, the initiator of chromosomal DNA replication in Escherichia coli, is activated by binding to ATP in vitro. We introduced site-directed mutations into two amino acids of the protein conserved among various ATP-binding proteins and examined functions of the mutated DnaA proteins, in vitro and in vivo. Both mutated DnaA proteins (Lys-178 --> Ile or Asp-235 --> Asn) lost the affinity for both ATP and ADP but did maintain binding activity for oriC. Specific activities in an oriC DNA replication system in vitro were less than one-tenth those of the wild-type protein. Assay of the generation of oriC sites sensitive to P1 nuclease, using the mutated DnaA proteins, revealed a defect in induction of the duplex opening at oriC. On the other hand, expression of each mutated DnaA protein in the temperature-sensitive dnaA46 mutant did not complement the temperature sensitivity. We suggest that Lys-178 and Asp-235 of DnaA protein are essential for the activity needed to initiate oriC DNA replication in vitro and in vivo and that ATP binding to DnaA protein is required for DNA replication-related functions.

A clinical analysis of the recovery from sensory disturbance after sagittal splitting ramus osteotomy using a Semmes-Weinstein pressure aesthesiometer

A number of studies of evaluation methods for sensory disturbance after sagittal splitting ramus osteotomy (SSRO) are known. To compare postoperative sensory disturbances among patients in different hospitals, a highly reproducible and standardized sensory test is required. In the present study, we measured the tactile threshold in the region innervated by the mental nerves in 45 patients (90 sides) after SSRO using a Semmes-Weinstein pressure aesthesiometer. The percentage of recovery to the normal level defined by Bell was 72.2% at one week, 82.2% at 4 weeks, and 90.0% at 8 weeks after SSRO. The recovery process was evaluated by classifying the postoperative sensory disturbance into 5 grade levels according to Bell's interpretation scale. The results showed that the SW sensory test is useful for evaluation of the recovery process from sensory disturbance after SSRO. Some improvements of this test were also discussed.

Variable expression on lung cancer cell lines of HLA-A2-binding MAGE-3 peptide recognized by cytotoxic T lymphocytes

Cytotoxic T lymphocytes (CTL) specific for HLA-A2-binding MAGE-3 peptide (FLWGPRALV) were generated by repetitive stimulation of PBMC with the peptide in the presence of EBV-transformed B blasts and IL-2. Using these CTL, we investigated the expression of the HLA-A2-binding MAGE-3 peptide on lung cancer cell lines. Of 14 cell lines investigated, 1-87, PC-9, OU-LC-KI, 11-18 and LK87 were derived from HLA-A2 positive patients. But cytofluorometry analysis showed that 1-87, PC-9 and OU-LC-KI, but not 11-18 or LK87 expressed the HLA-A2 antigen. All five cell lines expressed MAGE-3 gene mRNA. Twelve of thirteen CTL lines from two HLA-A2 positive donors showed no cytotoxicity against any of the 14 lung cancer cell lines. CTL line TI-1 showed cytotoxicity against 1-87 but not against any of the other cell lines. Treatment of 1-87 with IFN-gamma greatly augmented the cytotoxicity of TI-1 and induced it in the other 12 CTL lines, confirming the expression of the peptide on 1-87. No cytotoxicity was induced by IFN-gamma treatment of PC-9 or OU-LC-KI. However, PC-9 and OU-LC-KI pulsed with the peptide were killed efficiently by all of the CTL lines, suggesting no expression of the peptide on those cells. A low level of cytotoxicity was induced on 11-18 but not LK87 by IFN-gamma treatment, although expression of the HLA-A2 antigen was not observed by cytofluorometry. These findings showed that expression of the HLA-A2-binding MAGE-3 peptide recognized by CTL was variable on lung cancer cell lines.

[Bacterial intracranial aneurysm associated with infective endocarditis: a case showing enlargement of aneurysm size]

The authors report a case of bacterial intracranial aneurysm associated with infective endocarditis. A 48-year-old male was admitted on March 26, 1994, with complaints of difficulty in speaking and mild swelling of the right leg following mild fever. On examination he showed motor aphasia and mild weakness of the right upper and lower limbs. Cardiac auscultation revealed a grade 3/6 holosystolic murmur. Laboratory data revealed signs of infection through white blood cell count and CRP. Enterococcus faecalis was isolated from the blood culture at the time of admission. A computerized tomographic (CT) scan and magnetic resonance (MR) imaging showed a round mass with perifocal edema. Angiography revealed an aneurysm from the precentral artery of the left middle cerebral artery. A mycotic aneurysm due to bacterial endocarditis was diagnosed. The patient was treated with high doses of antibiotics. However, angiography 2 weeks after the initial study demonstrated the enlargement of the aneurysm and severe narrowing of the angular artery. On April 19, excision of the aneurysm was performed. Operative findings showed degeneration and thickening of the walls of the aneurysm. After the operation, antibiotic therapy was continued. The patient was asymptomatic upon discharge and has continued to do well. Repeated angiography on September 12 showed no further aneurysm. There is a danger of rupture in mycotic aneurysm due to bacterial endocarditis. It is important to repeat angiography and to manage the primary disease. If an aneurysm enlarges with serial angiography, it should be treated surgically without further delay.

Microvascular free tissue transfer in oral and maxillofacial reconstruction

Forty-two patients with head and neck cancer were submitted to microvascular reconstructive procedures. We divided patients in three groups; a first group of 30 patients, in whom the oral floor (8 patients), the part of tongue (14 patients), the lower gingiva (6 patients) and the oropharynx (2 patients) were reconstructed using various sizes of forearm flaps; a second group of 7 patients who underwent buccal mucosa reconstructions with the forearm flaps; and a third group of 5 patients who received rectus abdominis flaps for total tongue reconstruction. Three illustrative cases, one from each group, are presented in detail. Good results were obtained in 39 patients (94%), with both functional and morphological rehabilitation. There were three flap losses due to thrombosis of the microvascular anastomoses. There was no surgical mortality. The average operating time was about 10 hours in total. We concluded that there is a place for these complex procedures in the treatment of selected cases of head and neck tumors.

[Chronic treatment with nicotine enhances the sensitivity of dopamine autoreceptors that modulate dopamine release from the rat striatum]

This study was undertaken to investigate the effect of chronic nicotine treatment on electrically evoked dopamine (DA) release from striatal slices and locomotor activity in rats under the influence of DA autoreceptor agonists and antagonist. Nicotine was supplied chronically by Alzet osmotic minipump for two weeks. B-HT920 and quinpirole decreased and (-)-sulpiride increased the evoked DA release from striatal slices. The B-HT920 and quinpirole-induced decrease and the (-)-sulpiride-induced increase in evoked DA release were enhanced by chronic treatment with nicotine. Nicotine itself has little effect on the evoked DA release. B-HT920 and quinpirole decreased and (-)-sulpiride, methamphetamine and apomorphine increased the locomotor activity in the rat. The B-HT920 and quinpirole-induced decrease and the (-)-sulpiride-induced increase in locomotor activity were enhanced by chronic treatment with nicotine. On the other hand, the methamphetamine and apomorphine-induced increase in locomotor activity were unaltered by chronic treatment with nicotine. Chronic nicotine treatment itself has no effect on locomotor activity. These data indicate that chronic treatment with nicotine caused a supersensitivity in presynaptic DA autoreceptors that modulate DA release from DA terminals in the rat striatum, and no change in the function of postsynaptic DA receptors.

Differential effects of dopamine antagonists on evoked dopamine release from slices of striatum and nucleus accumbens in rats

The effects of dopamine-receptor antagonists on electrically-evoked dopamine release were compared in the nucleus accumbens and striatal slices of rats. (-)-Sulpiride induced a concentration-dependent increase in the evoked dopamine release from both regions, the increase in the nucleus accumbens being significantly greater than that in the striatum. Clozapine also increased evoked dopamine release from the nucleus accumbens, but not from the striatum. The haloperidol-induced increase in evoked dopamine release from the nucleus accumbens was less than that from the striatum. These findings indicate that, in terms of dopamine transmission, (-)-sulpiride and clozapine, but not haloperidol, predominantly affect the nucleus accumbens rather than the striatum. We have previously reported that the contribution of D3 receptors to the regulation of dopamine release from dopamine nerve terminals is much greater in the nucleus accumbens than that in the striatum. (-)-Sulpiride and clozapine have relatively higher affinity for D3 receptors than does haloperidol. The regional differences in responsiveness of dopamine release to dopamine antagonists could be due to the different affinities to D2 or D3 receptors of the dopamine antagonists.

[Inhibitory effect of haloperidol on evoked dopamine release from striatal slices of the rat]

Haloperidol-induced changes in evoked dopamine (DA) release from striatal slices in rats were investigated. The dose-response curves for haloperidol to changes in the evoked DA release were found to be biphasic (small doses increased the release and large doses inhibited), which were shifted to the left by longer periods of superfusion with haloperidol. This rapid tolerance or inhibition of haloperidol-induced increases in evoked DA release was reduced or attenuated by the superfusion with acetylcholine (ACh) antagonists or B-HT920 and was enhanced by ACh agonists. The microinjection of kainic acid into the rat striatum 4 days before the experiment reduced the rapid tolerance or inhibition of the haloperidol-induced increase in evoked DA release. These data indicate that intrinsic ACh neurons in the striatum may play an important role in the induction of the rapid tolerance or inhibition of haloperidol-induced increase in evoked DA release from striatal slices in rats.

Acute purulent discitis with epidural abscess of the cervical spine in an adult--case report

A 52-year-old male presented with acute purulent discitis and epidural abscess of the cervical spine manifesting as neck pain and slight fever, followed by sudden onset of quadriparesis. Magnetic resonance (MR) imaging showed a low-signal-intensity area in the C6/7 disc space and epidural space ventral to the spinal cord with peripheral enhancement. Surgical exploration using an anterior approach revealed local discitis and epidural abscess, but no osteomyelitis of the neighboring vertebral bodies. Six months after the decompressive procedure to treat the purulent disc and epidural abscess, he had achieved almost full recovery. Such lesions are rare in adults, but should be considered especially when painful spinal symptoms are associated with fever. Early and definitive diagnosis can be achieved by MR imaging with enhancement.

Cerebellopontine angle meningioma associated with cranial accessory nerve neurinoma--case report

A 46-year-old female presented with a rare association of cerebellopontine (CP) angle meningioma with accessory nerve neurinoma manifesting as headache, occasional diplopia, speech disturbance, swallowing difficulty, and unsteady gait. Magnetic resonance imaging demonstrated a large tumor in the left CP angle. The tumor was totally removed through a lateral suboccipital approach. During the operation another smaller tumor was found originating from the cranial accessory nerve and was also totally removed. Histological examination found that the larger tumor was a meningotheliomatous meningioma and the smaller an Antoni type A neurinoma. The symptoms were apparently due to the larger tumor. Careful examination of neuroimages is necessary even after the main lesions responsible for the symptoms are identified.

The carcinostatic effects of 1-(2-tetrahydrofuryl)-5-fluorouracil and uracil (UFT) on tongue carcinoma induced by 4-nitroquinoline 1-oxide (4NQO) in rats

UFT is a carcinostatic agent used in adjuvant chemotherapy for head and neck cancer. In the present study. UFT was given orally to treat tongue carcinoma in rats induced by 4-nitroquinoline 1-oxide. The antitumor effects of UFT were studied macroscopically and histologically. In addition, the antitumor effects of UFT were evaluated in relationship to lesions of the clinical and, invasive types, and to there vascular structure. In clinical lesions, the antitumor effect of UFT was higher in extrovert tumor-mass lesions and lower in ulcerous lesions. With regard to vascular structure, the effect was higher in cases demonstrating irregular net-like patterns and branch-like patterns and lower in cases in which the pattern had been destroyed. There was a correlation between antitumor effect and invasive type. As invasive tendency the 3H-thymidine labeling index, and mitotic index increased, antitumor effect and degree of tumor cell degeneration decreased.

Intramedullary ganglioglioma of spinal cord--case report

Gangliogliomas occur least commonly in the spinal cord. A case of ganglioglioma of C8-Th1 spinal cord in a 24-year-old male is reported. Magnetic resonance imagings are an important element of diagnosis and treatment.

Subependymal giant-cell astrocytoma associated with tuberous sclerosis. Do subependymal nodules grow?

A case of a 10 year-old-boy with subependymal giant-cell astrocytoma associated with tuberous sclerosis is reported. Sequential CT scan showed the growth of subependymal nodules to intraventricular neoplasm, which consequently obstructed the CSF pathway. The surgical indications for this lesion and the role of CT in following up subependymal nodules of tuberous sclerosis are discussed.