Dissecting aneurysms of the anterior cerebral artery and accessory middle cerebral artery. Case report

A 66-year-old woman presented with dissecting aneurysms of the anterior cerebral artery (ACA) and accessory middle cerebral artery (MCA) manifesting as subarachnoid hemorrhage but without radiological evidence of the dissecting aneurysms. Intraoperative observation revealed that the vessel walls were dark purple in color, a typical finding of dissecting aneurysm. The abnormal A1 segment was trapped and the dissecting aneurysm of the accessory MCA was wrapped. In the case of SAH of unknown origin, dissecting aneurysm should always be kept in mind even if the angiogram does not show any abnormal finding. This is the first reported case of dissecting aneurysm of the accessory MCA.

Suppressed bone induction by follistatin in spontaneously hypercholesterolemic rat bone

Bone inducing activity in demineralized bone matrix (DBM) of young spontaneously hypercholesterolemic (SHC) rats has been shown to be lower than that of aged SHC rats. This study examined the involvement of bone follistatin, an activin-binding protein, in bone induction. Immunoreactive follistatin was higher in DBM from 10-week-old SHC rats (DBM-10wk) than in DBM from 6-month-old SHC rats (DBM-6mo). When DBM without follistatin supplement was implanted, the C-propeptide of type II procollagen and calcium contents on day 12 in implants of DBM-6mo were 68% and 40% higher than those of DBM-10wk, respectively. In contrast, follistatin supplement to DBM decreased C-propeptide of type II procollagen and calcium contents in implants of both DBM-10wk and DBM-6mo, and the levels of these parameters were comparable between DBM-10wk and DBM-6mo, indicating reduced formation of cartilage and bone. These findings suggest that 1) follistatin content in bone matrix decreases with advancing age in SHC rats, and 2) the follistatin interferes with endochondral bone formation. We demonstrate that the lower bone induction of DBM from young SHC rats was partly due to the abundance of follistatin in bone matrix.

Surgical removal of cavernous angioma in the medulla oblongata. A case report

Recent advances in neuroradiology have enabled us to approach cavernous angioma in the medulla oblongata, rather rare vascular lesion in the central nervous system. We describe a such surgical case without additional neurological symptoms and discuss surgical indications in this paper. A 61-year-old woman presented with vertigo and swallowing disturbance. T1-weighted magnetic resonance image (MRI) showed a low intensity mass in the dorsolateral portion of the medulla oblongata, and T2-weighted imaging revealed a hemosiderin rim surrounding the lesion. Angiography showed no abnormalities. Surgery using far lateral approach achieved complete removal of the mass and hematoma. Histological examination of the surgical specimen disclosed cavernous angioma. This case suggests that direct surgery can be recommended for cavernous angioma located in the dorsal or lateral medulla oblongata to remove the hematoma and angioma if bleeding clearly provokes neurological symptoms.

Comparative studies of CAM 123-6 and carcinoembryonic antigen for the serological detection of pulmonary adenocarcinoma

Carcinoembryonic antigen (CEA) has been clinically used as a serum marker for lung cancer, especially for pulmonary adenocarcinoma. Since we had developed a tumor marker against pulmonary adenocarcinoma, CAM 123-6 belonging to KL-6 MUC 1 mucin, we compared its clinical value with that of CEA, in combination with squamous cell carcinoma-related antigen (SCC) and neuron-specific enolase (NSE). The subjects were 30 patients with adenocarcinoma, 23 with squamous cell carcinoma, 16 with small cell carcinoma, and 20 with benign lung disease. For discriminating lung cancer from benign lung disease, the combination of CAM 123-6, SCC, and NSE showed 64% diagnostic accuracy, and the combination of CEA, SCC, and NSE 65%. In differentiating pulmonary adenocarcinoma from other lung cancer, the diagnostic accuracy of CAM 123-6 was 81% and that of CEA was 74%, although there was no significant difference between them. These observations indicate that the diagnostic accuracy of CAM 123-6 is similar to that of CEA. Neither marker is sufficiently specific to differentiate pulmonary adenocarcinoma from other forms of lung cancer.

Reduction of hypoxic cells in solid tumours induced by mild hyperthermia: special reference to differences in changes in the hypoxic fraction between total and quiescent cell populations

C3H/He mice bearing SCC VII tumours received 5-bromo-2'-deoxyuridine (BrdU) continuously for 5 days via implanted mini-osmotic pumps in order to label all proliferating (P) cells. The tumours were then heated at 40 degrees C for 60 min. At various time points after heating, tumour-bearing mice were irradiated while alive or after being killed. Immediately after irradiation, the tumours were excised, minced and trypsinized. The tumour cell suspensions obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labelling, which could be regarded as quiescent (Q) cells, was determined using immunofluorescence staining for BrdU. The MN frequency in the total (P+Q) tumour cell population was determined from the irradiated tumours that were not pretreated with BrdU. The MN frequency of BrdU unlabelled cells was then used to calculate the surviving fraction of the unlabelled cells from the regression line for the relationship between the MN frequency and the surviving fraction of total (P+Q) tumour cells. In general, Q cells contained a greater hypoxic fraction (HF) than the total tumour cell population. Mild heating decreased the HF of Q cells more markedly than in the total cell population, and the minimum values of HFs of both total and Q cell populations were obtained 6 h after heating. Two days after heating, the HF of total tumour cells returned to almost that of unheated tumours. In contrast, the HF of Q cells did not return to the HF level of unheated tumours until 1 week after heating. It was thought that irradiation within 12 h after mild heating might be a potentially promising therapeutic modality for controlling radioresistant Q tumour cells.

Inhibition by erythromycin of human pulmonary artery endothelial cell injury induced by human neutrophils

Neutrophils are thought to play a key role in tissue injury. We investigated the role of human neutrophils in the induction of injury to the human pulmonary artery endothelial cells and the effect of erythromycin on neutrophil-induced endothelial cell damage. Incubation of unstimulated neutrophils with endothelial cells increased the release of lactate dehydrogenase (LDH) activity and preloaded fura-2 from endothelial cells. When neutrophils were activated by phorbol myristate acetate, the release of LDH and fura-2 was enhanced further. Superoxide dismutase partially inhibited the release of LDH and fura-2 induced by neutrophils, whereas erythromycin markedly inhibited the release of endothelial cell LDH and fura-2 induced by neutrophils. These results suggest that endothelial cell injury is, at least in part, mediated by the action of superoxide and that erythromycin protects against neutrophil-induced endothelial cell injury.

[Home terminal care for lung cancer--subcutaneous injection with morphine hydrochloride for cancer related pain from metastatic bone cancer in a terminal lung cancer patient]

Home management for cancer-related pain in a terminal cancer patient is usually performed by oral or intrarectal administration with analgesics. If such treatment fails to reduce cancer-related pain, we have to treat them with epidural, intravenous or subcutaneous injection of these agents in some cases. We encountered a terminal lung cancer patient with metastatic bone cancer who was treated with continuous subcutaneous injection of morphine hydrochloride at home. As a result, the patient's quality of life has been remarkably improved. The management of cancer-related pain with analgesics and terminal care at home are discussed.

A phase I and II clinical trial of a newly developed ultrasound hyperthermia system with an improved planar transducer

PURPOSE

The clinical usefulness of a newly developed ultrasound hyperthermia system was evaluated.

METHODS AND MATERIALS

The hyperthermia system uses a modified planer transducer operated at frequencies of 0.5, 1.0, and 1.5 MHz. The transducer has a nonvibrating part at the center to reduce the central hot spot. Frequency sweeping technique is also used to eliminate the annular hot spot around the center. Thirty-eight tumors in 29 patients were examined in this study. In 35 tumors, hyperthermia was given in conjunction with irradiation and/or chemotherapy, and in the remaining 3 tumors, hyperthermia alone was given. In all, a total of 153 hyperthermia sessions were performed.

RESULTS

The number of hyperthermia sessions per tumor ranged from 1 to 7 (mean, 4.0 +/- 1.3). The number of intratumor thermometry points per session ranged from 1 to 8 (mean, 4.3 +/- 1.5). The average intratumor temperature for tumors with a maximum depth of <3 cm, 3-6 cm, and >6 cm was 42.1 +/- 1.2, 41.7 +/- 1.4, and 39.9 +/- 2.0 degrees C, respectively. The percentage of monitored intratumor points with temperature exceeding 42 degrees C was 56 +/- 31%, 43 +/- 34%, and 21 +/- 24%, respectively. Of the 30 evaluable tumors treated with combined irradiation, 12 showed complete response, 14 partial response, and 4 no change. Observed complications included pain at the treatment site in 13 of the 153 treatment sessions and vesicle formation in 3 of the 38 treatment sites. No serious complication was seen.

CONCLUSIONS

These results indicate that the newly developed ultrasound hyperthermia system is clinically useful for the treatment of localized superficial and subsurface tumors with a maximum tumor depth of no more than 6 cm.

Protective effect of leuprolide acetate on 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinogenesis in rats

The anti-carcinogenic effect of TAP-144-SR biodegradable microcapsules of copoly (DL-lactic/glycolic acid) copolymer containing a potent LHRH agonist, TAP-144 (D-Leu6-(des-Gly10-NH2)-LHRH ethylamide, leuprolide acetate) was investigated in 7,12-dimethylbenz(a)anthracene (DMBA)-induced rat mammary tumours. At 50 days of age, all rats were given 20 mg doses of DMBA by gastric intubation. Rats on the Initiation Group were given a single s.c. injection of TAP-144-SR (3 mg/kg) 1 week before DMBA treatment, and rats in the Promotion Group were given repeated s.c. injections every fourth week from 1 week after DMBA treatment until the end of the experiment. In the Initiation Group, tumour incidence and multiplicity were reduced to 20.8% and 15.0% of the Control Group values, respectively. In the Promotion Group, tumour incidence and multiplicity were also reduced to 17.7% and 7.9%, respectively. It was suggested that TAP-144-SR may be a potential candidate as an agent for hormonal chemoprevention in breast cancer.

CD40-mediated stimulation of B1 and B2 cells: implication in autoantibody production in murine lupus

B1 cells usually show preferential responses to T cell-independent antigens. To ask whether B1 cells could respond to CD40-mediated stimulation for proliferation and differentiation, and whether CD40-mediated signals are involved in the production of autoantibodies by B1 cells, we compared responses to our newly established agonistic anti-mouse CD40 monoclonal antibody (mAb) between B1 and B2 cells from autoimmune-prone (NZB x NZW) F1 mice. Stimulation with this mAb induced a similar level of proliferative responses of both B1 and B2 cells, as well as an increase in expression of cell surface molecules I-A, CD54, CD23, CD80, and CD86. While co-stimulation with interleukin (IL)-4 markedly augmented proliferative as well as IgG1 and IgE antibody responses of both B and B2 cells, co-stimulation with IL-5 augmented proliferative and IgM antibody responses of only B1 cells. Splenic B1, but not B2 cells from young (NZB x NZW) F1 mice spontaneously produced substantial amounts of IgM including IgM anti-DNA antibodies, and the levels increased in case of stimulation with anti-CD40 mAb alone, or to a greater extent with the mAb plus IL-4 and IL-5. Collectively, these results indicate that splenic B1 cells from autoimmune (NZB x NZW) F1 mice have a comparable responsiveness to the CD40-mediated stimulation to that of B2 cells, which would be a potent regulatory mechanism involved in the spontaneous production of autoantibodies by B1 cells.

Analysis of lectin binding properties on human Burkitt's lymphoma cell lines that show high spontaneous metastasis to distant organs in SCID mice: the binding sites for soybean agglutinin lectin masked by sialylation are closely associated with metastatic lymphoma cells

Alterations in cell surface carbohydrates on human lymphoma cell lines with different spontaneous metastatic potential in the severe combined immunodeficiency (SCID) mouse model were analyzed. A difference in cell surface carbohydrates between high- (HBL-2, HBL-7 and HBL-8) and no- or low-(HBL-4, HBL-6, Daudi and Raji) spontaneous metastatic human lymphoma cell lines were analyzed on a FACScan using fluorescein-isothiocyanate (FITC)-conjugated lectins. The most consistent difference in lectin binding properties was found with soybean agglutinin (SBA) lectin. High-metastatic lymphoma cells (HBL-7 and HBL-8 cells) in vitro were found to bind the SBA lectin, but the cells in vivo (in primary tumors and metastatic tumors of SCID mice) showed considerably reduced SBA lectin binding. In addition, HBL-2 cells that almost did not bind SBA lectin in vitro and in vivo showed high spontaneous metastasis. Neuraminidase treatment revealed that SBA lectin binding sites were masked by sialic acid. On the other hand, no- or low-metastatic lymphoma cells in vitro and in vivo were found to bind SBA lectin. HBL-8 cell clones without SBA lectin binding showed high spontaneous metastasis to distant organs in SCID mice but HBL-8 cell clones with SBA lectin binding showed very low spontaneous metastasis. Sophora Japonica agglutinin (SJA) lectin is able to recognize the carbohydrates in common with SBA lectin, but it does not appear to be associated with metastatic capacity. These results suggest that the sialylation of particular carbohydrate residues on human lymphoma cells that are recognized by SBA lectin may be associated with the spontaneously metastatic capacity of human lymphoma cell lines in our SCID mouse model.

Effects of a high-protein diet on mineral metabolism and struvite activity product in clinically normal cats

OBJECTIVE

To examine effects of high-protein diets (> 50% crude protein of dry matter) on urinary mineral excretion and struvite activity product ([Mg2+] x [NH4+] x [PO(4)3-]).

ANIMALS

14 clinically normal cats, 4 adult female and male cats for experiments 1 and 2, respectively, and 6 female kittens aged 4 months for experiment 3.

PROCEDURE

Relations between dietary protein amount (25.9, 38.3, 51.4, and 65.4% crude protein [dry matter]) and urinary excretion of Mg, P, and Ca were examined in a 4 x 4-Latin square design (experiment 1). Struvite activity product, the index of solubility of struvite crystals, was determined when a high-protein diet (54.9%) was fed (experiment 2). Utilization of minerals in cats fed a high-protein diet long term was examined (experiment 3).

RESULTS

Water intake and urine volume increased with increasing dietary protein concentration. Urinary Mg2+ excretion was not affected (experiment 1) or was decreased (experiment 3) by higher protein intake, leading to lower urine Mg2+ concentration in groups fed higher protein amounts. Urine pH was decreased by high-protein intake. As a result, PO(4)3- concentration was decreased by high-protein intake (experiment 2), although total daily urinary excretion of P was increased. Consequently, struvite activity product tended to decrease in cats fed high-protein diets, indicating increase in struvite solubility. High-protein intake decreased Ca and P retention by increasing their fecal and urinary excretions, respectively.

CONCLUSION

As a consequence of the increase in urine volume and urine acidification, high-protein diets have potential ability to increase solubility of struvite crystals.

Cross-linking of intercellular adhesion molecule 1 (CD54) induces AP-1 activation and IL-1beta transcription

Leukocytes adhere to target cells through their integrins and play a crucial role in self-defense, inflammation, and differentiation. Intercellular adhesion molecule-1 (ICAM-1; CD54) is a representative ligand for integrins and is expressed on many cell types, some of which are targets for leukocyte adhesion. Recent studies suggest that adhesion molecules function not only as a cellular glue, but also as a signal transducer. However, it remains to be clearly defined whether engagement of ICAM-1 is able to induce activation signals in target cells. In rheumatoid synovium, synovial cells are known to express abundant ICAM-1 and produce multiple inflammatory cytokines, such as IL-1beta. In this study, we provide the first evidence that ICAM-1 engagement induces activation of the transcription factor AP-1 and transcription of the IL-1beta gene using a specific Ab to cross-link ICAM-1 on a rheumatoid synovial cell line (E11 cells). This evidence includes ICAM-1 cross-linking-dependent induction of 1) in situ IL-1beta transcription and protein synthesis, 2) transiently transfected chloramphenicol acetyltransferase (CAT) reporter plasmids containing both the IL-1beta LPS-responsive enhancer (between -3134 and -2729) as well as multiple copies of an AP-1 site from this enhancer (between -3117 and -3111), and 3) the binding of a Jun/Fos family complex to this AP-1 site. Thus, ICAM-1 not only functions as a glue for integrin binding, but also as a transducer for AP-1 activation signals important for IL-1beta gene transcription.

Relationship between the angiotensin converting enzyme gene polymorphism and the effects of enalapril on left ventricular hypertrophy and impaired diastolic filling in essential hypertension: M-mode and pulsed Doppler echocardiographic studies

OBJECTIVE

To investigate the relationship between the angiotensin converting enzyme (ACE) gene polymorphism and the effects of the ACE inhibitor enalapril on left ventricular hypertrophy and impaired diastolic filling.

DESIGN AND METHODS

Enalapril (5-10 mg/day) was administered for 12 months to 60 previously untreated patients with essential hypertension. M-mode and pulsed Doppler echocardiography were performed before and after treatment, and changes in various parameters after treatment with enalapril were examined. ACE gene polymorphism was examined by the polymerase chain reaction method and the patients were classified as having the 190 bp deletion homozygous (DD) genotype, the 490 bp insertion homozygous (II) genotype or the 490 bp insertion 190 bp deletion heterozygous (ID) genotype.

RESULTS

The DD genotype was observed in 10 patients (17%), the ID genotype in 24 patients (40%) and the II genotype in 26 patients (43%). Plasma ACE activity before treatment with enalapril was significantly higher in seven patients with DD genotype than it was in 18 patients with ID genotype and in 14 patients with II genotype. In all of the 60 patients, the left ventricular mass index, the peak atrial systolic velocity:early diastolic velocity ratio and the deceleration time from the peak of the early diastolic wave to the baseline in transmitral flow velocity were decreased significantly after treatment with enalapril. The changes in left ventricular mass index and atrial systolic velocity:early diastolic velocity ratio after enalapril administration were significantly greater in the DD genotype group than they were in the other two genotype groups.

CONCLUSION

Enalapril-induced regression of left ventricular hypertrophy and improvement in left ventricular impaired diastolic filling were significantly greater in the DD genotype group than they were in the ID and II genotype groups, suggesting that the circulating and tissue renin-angiotensin systems, particularly the former system, are most active in hypertensive patients with the DD genotype.

Clinical usefulness of determining the rate of thermal clearance within heated tumors

Between June 1987 and June 1988, 28 patients (28 tumors) with liver, retroperitoneal, intrapelvic, or superficial tumors were treated with hyperthermia combined with radiotherapy and/or chemotherapy. Hyperthermia was administered once or twice a week for 30-60 min per session, up to a total of 2-11 sessions, with an 8-MHz RF capacitive heating device. Blood flow in the tumors was evaluated from the rate of thermal clearance (TCR) using the bio-heat transfer equation. The TCR was measured in the middle of the first heating session and at the end of the last heating session by turning off the output power of the heating device. For 9 patients, contrast-enhanced CT scans were taken and CT numbers at the centers of tumors were measured before and after the entire course of hyperthermia. Changes in TCR were closely related to average tumor center temperature, changes in CT number, and tumor response. When smaller and more superficial tumors were treated by hyperthermia combined with radiotherapy and/or chemotherapy that consisted of many heating sessions and during which a high average tumor center temperature was achieved, a better tumor response was obtained. The better the tumor response, the higher the local control rate became. The cause-specific survival rate of patients who achieved good tumor responses was higher than that of patients who showed poor tumor responses. Changes in TCR and CT number in heated tumors were useful and important indicators of tumor response to hyperthermia.

Near-death asthmatic reaction induced by disodium cromoglycate

A near-death asthmatic reaction was induced by disodium cromoglycate (DSCG) as evidenced by positive skin and inhalation provocation tests. The patient's history revealed an episode of exacerbation by inhalation of DSCG. In spite of such an experience, he inhaled DSCG for relief of asthmatic attack, resulting in near-death exacerbation. This patient emphasizes the need to re-recognize that DSCG is not a reliever and the DSCG could cause fatal asthma.

Stereoscopic synthesized brain-surface imaging with MR angiography for localization of a peripheral mycotic aneurysm: case report

A patient with subacute bacterial endocarditis and a peripheral mycotic aneurysm is presented. We used a combined multi-slice surface anatomy scanning (SAS) and contrast-enhanced MR angiography image to determine the exact location of the small lesion by applying a skin marker on the scalp and visualizing the relationship of the marker to the brain surface structures and to the lesion. This technique was useful for the removal of a small peripheral aneurysm using only a limited craniotomy.

Cross-linking of intercellular adhesion molecule 1 (CD54) induces AP-1 activation and IL-1beta transcription

Leukocytes adhere to target cells through their integrins and play a crucial role in self-defense, inflammation, and differentiation. Intercellular adhesion molecule-1 (ICAM-1; CD54) is a representative ligand for integrins and is expressed on many cell types, some of which are targets for leukocyte adhesion. Recent studies suggest that adhesion molecules function not only as a cellular glue, but also as a signal transducer. However, it remains to be clearly defined whether engagement of ICAM-1 is able to induce activation signals in target cells. In rheumatoid synovium, synovial cells are known to express abundant ICAM-1 and produce multiple inflammatory cytokines, such as IL-1beta. In this study, we provide the first evidence that ICAM-1 engagement induces activation of the transcription factor AP-1 and transcription of the IL-1beta gene using a specific Ab to cross-link ICAM-1 on a rheumatoid synovial cell line (E11 cells). This evidence includes ICAM-1 cross-linking-dependent induction of 1) in situ IL-1beta transcription and protein synthesis, 2) transiently transfected chloramphenicol acetyltransferase (CAT) reporter plasmids containing both the IL-1beta LPS-responsive enhancer (between -3134 and -2729) as well as multiple copies of an AP-1 site from this enhancer (between -3117 and -3111), and 3) the binding of a Jun/Fos family complex to this AP-1 site. Thus, ICAM-1 not only functions as a glue for integrin binding, but also as a transducer for AP-1 activation signals important for IL-1beta gene transcription.

Ets-1 regulates angiogenesis by inducing the expression of urokinase-type plasminogen activator and matrix metalloproteinase-1 and the migration of vascular endothelial cells

The coordinate induction of protease activities and cell migration is a principal feature of endothelial cells (ECs) invading the interstitial space in the initial step of angiogenesis. However, the molecular mechanisms of these events are not fully characterized. Ets-1 is a member of the ets gene family of transcription factors, which binds to the Ets binding motif in the cis-acting elements and regulates the expression of certain genes. Four typical angiogenic growth factors, aFGF, bFGF, VEGF, and EGF, induced the expression of ets-1 mRNA in either human umbilical vein endothelial cells (HUVECs), ECV-304 cells (immortalized HUVECs), or human omental microvascular endothelial cells (HOMECs). The expression of ets-1 reached its maximum at 2 hr after factor addition and then decreased to the basal level by 12 hr. For characterization of the role of Ets-1 in angiogenesis, ets-1 antisense and sense oligodeoxynucleotides (ODNs) were constructed. The ets-1 antisense ODN but not sense ODN efficiently blocked the synthesis of Ets-1 protein by human ECs in response to angiogenic growth factors. Moreover, the ets-1 antisense ODN but not sense ODN almost completely abolished the binding of endothelial cell extract to DNA containing the Ets binding motif. The expression of urokinase-type plasminogen activator and matrix metalloproteinase-1 and the migration of ECs in response to growth factors were significantly inhibited by ets-1 antisense ODN but not by sense ODN. Tube formation by HOMECs in type 1 collagen gel stimulated with EGF was abrogated by ets-1 antisense ODN. Finally, the expression of Ets-1 protein in ECs during angiogenesis in vivo was confirmed by an immunohistochemical analysis using a murine angiogenesis model. These results indicate that the induction of ets-1 mRNA is a mutual phenomenon in ECs stimulated with angiogenic growth factors. Ets-1 appears to play an important role in angiogenesis, regulating the expression of proteases and the migration of ECs.

Expression of neurofilament proteins in proliferating C2C12 mouse skeletal muscle cells

Expression of neurofilament proteins, NF140K, NF68K, and NF200K, in C2C12 mouse skeletal muscle cells was studied. Immunofluorescence and immunoblot analyses revealed that NF140K was expressed in proliferating C2C12 cells and its localization was similar to desmin, a muscle-specific intermediate filament protein. NF140K became undetectable in C2C12 cells as muscle cell differentiation proceeded. Reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot analyses confirmed the expression of NF140K, NF68K, and NF200K in proliferating C2C12 cells. Sequences of the RT-PCR products of NF140K and NF68K were identical to that of authentic mouse NF140K and NF68K, respectively. The NF140K and NF68K mRNA were down-regulated during myogenesis in contrast to the up-regulation of mRNA encoding troponin-T. Furthermore, subcloned C2C12 cells, which express NF140K at a higher level, exhibited retarded myogenesis, i.e., delayed onset of myosin heavy chain synthesis and myoblast fusion. These results suggest that neurofilament proteins may play an inhibitory role in commitment of muscle cell differentiation. The presence of neurofilament proteins in skeletal muscle cells indicates that desmin, vimentin, and neurofilament proteins can be expressed in a single muscle cell.

Cloning and chromosomal mapping of the mouse DNA-dependent protein kinase gene

Severe combined immune deficiency (scid) mice are assumed to have two types of abnormalities: one is high radiosensitivity and the other is abnormal recombination in immunoglobulin and T-cell receptor genes. The human chromosome 8 q1.1 region has an ability to complement the scid aberrations. Moreover, the localization of the subunit DNA-dependent protein kinase [DNA-PKcs] participating in DNA double-strand break repair in the same locus was clarified. In scid mouse cells, the number of DNA-PKcs products and extent of DNA-PK activity remarkably decrease. These observations gave rise to the assumption that DNA-PKcs is the scid factor itself. In order to determine whether the DNA-PKcs gene is the scid gene, we isolated the mouse DNA-PKcs gene and investigated its chromosomal locus by fluorescence in situ hybridization (FISH). Consequently, it became clear that the mouse DNA-PKcs gene existed in the centromeric region of mouse chromosome 16, determined by cross-genetic study, as a scid locus. This finding strongly suggests that mouse DNA-PKcs is the scid gene.

[A case report of a successful surgery for thoracoabdominal aortic aneurysm under partial cardiopulmonary bypass with selective perfusion of major abdominal branches]

A 69-year-old man showed gradually developing thoracoabdominal aortic aneurysm (TAAA) after coronary artery bypass grafting. The patient underwent graft replacement of TAAA uneventfully under partial cardiopulmonary bypass with selective perfusion of major abdominal branches. The major abdominal branches and two pairs of intercostal arteries were reconstructed. The patient showed no organ failure or spinal damage postoperatively. Partial cardiopulmonary bypass with selective perfusion of abdominal branches successfully protected both the visceral organs and the spinal cord from ischemia in a TAAA surgery.