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Biomedical subjects

H Nakajima

Publications and source records attributed to H Nakajima.

At least 91 records · Page 5Linked to original sources
PubMed2001

Aortic subannular left ventricular aneurysm in a patient of Asian ancestry.

An asymptomatic 50-year-old Japanese man was diagnosed with an aortic subannular left ventricular aneurysm during a routine physical checkup. Operative findings showed the subaortic aneurysm had developed beneath the noncoronary cusp of the aortic valve and expanded into the epicardium between the aortic root and left atrium. The operation involved patch closure of the orifice of the annular subaortic aneurysm, aortic valvuloplasty, and plication of the dilated ascending aorta.

Aortic Aneurysm↗
PubMed2001

Anti-arthritic effects of KF20444, a new immunosuppressive compound inhibiting dihydroorotate dehydrogenase, on rat collagen-induced arthritis.

OBJECTIVE AND DESIGN: A newly synthesized inhibitor of pyrimidine de novo biosynthesis, KF20444 (6,7-dihydro-10-fluoro-3-(2-fluorophenyl)-5H-benzo [6,7] cyclohepta [1,2-b] quinoline-8-carboxylic acid), was evaluated as an inhibitor of dihydroorotate dehydrogenase (DHO-DHase) and tested in the rat collagen-induced arthritis (CIA) model. MATERIAL AND METHODS: Female Sprague Dawley rats, 5 weeks-old, were used for evaluation of KF20444 in the CIA model. Arthritis was evaluated by arthritis score, serum anti-type II collagen antibody titer, body weight loss, radiographical and histological changes. TREATMENT: KF20444 was orally administered 5 times per week (0.3, 1, 3 mg/kg/day). RESULTS: KF20444 inhibited rat liver dihydroorotate dehydrogenase in vitro with Ki = 8.5 +/- 3.2 nM, which was a comparable effect to that of brequinar sodium (Ki = 25.3 +/- 5.3 nM). The anti-proliferative effect of KF20444 was caused by cell cycle arrest at the S-phase. Treatment with 3 mg/kg/day of KF20444 completely prevented the development of CIA based on reduction of the arthritis score. The 50% effective dose (ED50) of KF20444 on arthritis score was 0.64 mg/kg. KF20444 ameliorated body weight loss associated with disease onset. The compound also inhibited the increase in serum anti-type II collagen antibody level, and reduced both pannus formation and bone erosion. Importantly, KF20444 suppressed the development of arthritis, even when it was administered after booster immunization of collagen. CONCLUSIONS: KF20444 is a novel immunosuppressant which inhibits DHO-DHase and its effects in CIA suggest that it could be useful in the treatment of rheumatoid arthritis.

Animals↗
PubMed2001

Leptomeningeal contrast enhancement in moyamoya: its potential role in postoperative assessment of circulation through the bypass.

Leptomeningeal contrast enhancement (LMCE) is one of the MRI features of moyamoya. Its clinical significance, however, is not elucidated. Our purpose was to characterise LMCE on MRI and to evaluate its role in the assessment of circulation through a surgically established bypass in moyamoya. We studied 16 patients with idiopathic moyamoya (seven males, nine females, includingt four children, aged 7 to 54 years, mean 24 years) who underwent T1-weighted MRI before and after intravenous contrast medium. The presence of LMCE, its intensity and anatomical distribution, catheter angiographic findings, and relation of LMCE to the bypass surgery were assessed. More LMCE was seen in the cerebrum in most patients with moyamoya than in normal controls. LMCE in the brain stem and cerebellum was minimal, similar to that seen in the controls. LMCE was less prominent following surgery than before operation or in patients who did not undergo surgery. In three patients examined both before and after operation LMCE became less prominent following bypass surgery. As LMCE becomes less prominent after "effective" bypass surgery, this may be used for evaluation of effectiveness of surgery in moyamoya.

Adult↗
PubMed2001

Comparison of the isometric cervical extension strength and a cross-sectional area of neck extensor muscles in college wrestlers and judo athletes.

Increasing neck muscle strength can play an important role in preventing neck injuries in contact sports. The purpose of this study was to examine the actual conditions of the isometric cervical extension strength (ICES) and the cross-sectional area (CSA) of neck extensor muscles in male athletes participating in college wrestling and judo. The subjects comprised 18 wrestlers and 37 judo athletes from Nippon Sports Science University in Japan. The ICES was measured at eight angles (126 degrees, 108 degrees, 90 degrees, 72 degrees, 54 degrees, 36 degrees, 18 degrees, 0 degrees ). Transverse slices of 10 mm thickness were obtained at the position of each intervertebral disc between C2 and C3, C3 and C4, C4 and C5 and C5 and C6 using magnetic resonance imaging. The ICES of the wrestlers were significantly higher than those of the judo athletes. The ICES curve against the angle in wrestlers tended to differ from that of judo athletes. The CSA of neck extensor muscles in the wrestlers was significantly larger at all intervertebral levels examined than those of the judo athletes. A significant difference was observed in the CSA of the deepest area of neck extensor muscles between the groups although the difference was not significant in the superficial area. In this study, the ICES and the CSA in wrestlers were shown to be significantly higher and larger respectively than in the judo athletes, indicating a significant difference between these two sports.

Adolescent↗
PubMed2001

Extended unroofing procedure for creation of a new ostium for anomalous left coronary artery.

A modified procedure to create an alternative ostium for the left coronary artery was successfully carried out in a patient having anomalous origin of the left coronary artery from the right coronary sinus of the aorta. The proximal portion of the artery had an intramural course. The newly constructed orifice was widely patent and functioning well 44 months later, without episodes of myocardial ischemia or aortic regurgitation.

Adolescent↗
PubMed2001

Chlamydocin analogues from the soil fungus Peniophora sp.: structures and plant growth-retardant activity.

Three chlamydocin analogues that show activity for reducing the height of rice seedlings without blotch and wilting were isolated from the culture filtrate of the soil fungus Peniophora sp. and were characterized by spectral data and chemical conversion. For two of these, it is their first isolation as natural products. The proposed role of the functional groups of the 2-amino-8-oxodecanoic acid moiety of these analogues is discussed in terms of growth retardant activity.

Basidiomycota↗
PubMed2001

Two-staged gamma knife radiosurgery for the treatment of large petroclival and cavernous sinus meningiomas.

BACKGROUND: In this study, we report on the effectiveness and usefulness of two-staged gamma knife radiosurgery (GKS) for large petroclival and cavernous sinus meningiomas that have a high rate of surgical morbidity. METHODS: We have treated 7 patients suffering from large petroclival and cavernous sinus meningiomas using two-staged radiosurgery since March 1995. The tumors were located in the petroclival region in 4 patients, the cavernous sinus region in 2 patients, and in the petrocavernous region in the remaining patient. Three of the patients had been surgically treated and 4 patients (57%) were only followed with MR imaging. The volume of the tumors ranged between 34.5 to 101 cm(3) (mean 53.5 cm(3)). The treatment volume was between 6.8 to 29.6 cm(3) (mean 18.6 cm(3)). The treatment interval between the first GKS and second GKS was 6 months. The marginal doses for the tumors were 8 to 12 Gy (mean, 9 Gy). RESULTS: Six patients demonstrated tumor growth control during the follow-up period after the first radiosurgery (mean 39 months). Tumor regression was observed in 3 patients (43%). Three patients (43%) had improved clinically by the time of the follow-up examinations. No patient suffered from symptomatic radiation injury. CONCLUSION: Although we have treated only 7 patients using two-staged GKS, we believe this treatment may be a very useful option for large petroclival and cavernous sinus meningiomas in selected patients.

Aged↗
PubMed2001

Intracranial electroencephalographic changes in deep anesthesia.

OBJECTIVE: It is well known that electroencephalograms (EEGs) show electrical silence in deep anesthesia as well as brain death. This is the first report on intracranial EEG changes in deep anesthesia. METHODS: We developed a new direct brain monitoring system capable of recording intracranial EEGs. This study included 13 patients with head trauma or cerebrovascular accident under deep anesthesia. RESULTS: The intracranial EEGs showed different patterns of wave activity in depth compared with the cortical surface. In 3 of the cases, the scalp EEG showed a flat tracing at 2.0-2.5% of isoflurane. In two of the cases, the intracranial EEGs showed electrical silence when the scalp EEG was flat. Decreasing the concentration of isoflurane to 1.5%, the intracranial EEG showed single paroxysmal appearance of 'revival' theta waves on the electrocorticogram (ECoG) or electroventriculogram (EVG). The intracranial 'revival' wave was followed by high-voltage burst-waves. In another case, at 2.0-2.5% of isoflurane, the amplitude of the waves was greatest on the EVG. CONCLUSION: There is wave activity difference in the brain depth, which the scalp EEG is unable to show. Intracranial EEGs are able to show the first signs of revival after a nearly flat tracing in deep anesthesia.

Adult↗
PubMed2001

Prominent immunogenicity of monosialosyl galactosylgloboside, carrying a stage-specific embryonic antigen-4 (SSEA-4) epitope in the ACHN human renal tubular cell line-a simple method for producing monoclonal antibodies against detergent-insoluble microdomains/raft.

The binding of Shiga toxin (Stx) to Gb3Cer in detergent-insoluble microdomains (DIM)/raft of the ACHN human renal tubular cell line causes the temporal activation of the Src-family kinase Yes [1]. As a strategy for examining signaling mechanisms in DIM/raft, monoclonal antibodies (MAbs) are reliable tools for characterizing the constituent molecules in these microdomains. Thus, we employed DIM/raft suspensions of ACHN cells as an immunogen to develop MAbs. Simply subcutaneous injections of ACHN DIM/raft could elevate the serum titer after several boosts. The first screening was performed using dot-blot immunostaining with culture supernatants on a polyvinylidene difluoride (PVDF) membrane, on which DIM/raft or their chloroform/methanol (C/M) (2:1, v/v) extracts were dot-blotted. The next screening was performed by flowcytometric analysis of ACHN cells treated with or without a permeabilizing reagent. Many of the clones (21/31 clones=68%) thus obtained were also found to recognize to lipid fractions of the DIM/raft. Strikingly, all of the 21 clones that reacted to the lipid fraction were found to recognize monosialosyl galactosylgloboside (MSGG) or GL7, which carries the SSEA-4 epitope. Using DIM/raft as immunogens may enable us to easily obtain MAbs for glycolipids.

Animals↗
PubMed2001

A stone developed within the dilated intravesical ureter following ureteroscopy.

A 58-year-old man presented with a stone within the dilated intravesical ureter, which was probably attributable to a previous ureteroscopy. Transurethral incision of the right intravesical ureter and lithotripsy were carried out without subsequent urinary tract impairment. Although some complications resulting from ureteroscopy, such as ureteral stricture, ureteral perforation and vesicoureteral reflux, have been reported, this complication is considered to be very rare.

Humans↗
PubMed2001

Different effects of angiotensin II and catecholamine on renal cell apoptosis and proliferation in rats.

BACKGROUND: We have recently found that chronic infusion of angiotensin II (Ang II) into rats resulted in an impairment of renal function, whereas norepinephrine (NE) infusion did not. We investigated whether chronic infusion of Ang II and NE caused different degrees of renal cell apoptosis and proliferation. METHODS: Rats were made hypertensive via continuous infusion of either Ang II or NE for up to seven days. Renal cell apoptosis and proliferation were analyzed by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) technique and staining with antibody against proliferating cell nuclear antigen (PCNA), respectively. In some experiments, an inducer or inhibitor of heme oxygenase-1 (HO-1) was administered to investigate the possible role of HO-1 in renal cell homeostasis. RESULTS: Infusion of Ang II, but not NE, resulted in approximately a sevenfold increase in bax protein at seven days of infusion. The TUNEL assay revealed that Ang II infusion significantly increased the number of apoptotic cells, whereas NE infusion did not. TUNEL- and PCNA-positive cells were mainly seen in the tubulointerstitial region of Ang II-infused rats. Ang II induced increased positivity of TUNEL, and PCNA was blocked completely by losartan, but only partially by hydralazine. Induction of HO-1 reduced and inhibition of HO increased Ang II-induced cell proliferation. CONCLUSIONS: These data suggest that Ang II plays a pivotal role in the development of renal cell proliferation and apoptosis in the setting of hypertension. The renal HO system may modulate proliferative and pro-apoptotic effects of Ang II.

Angiotensin II↗
PubMed2001

Distal cement mantle thickness with a triangular distal centralizer inserted into the stem tip in cemented total hip arthroplasty.

Fifty-seven hips undergoing a primary cemented total hip arthroplasty with use of a triangular distal centralizer inserted into the stem tip were investigated, with a special focus on distal cement mantle thickness. The subjects were 43 women and 3 men. When evaluated on conventional anteroposterior and lateral radiographs, the relative incidence of thin cement mantles in zones 3 or 5 owing to the distal centralizer was 15.8% (9 hips). Unsatisfactory findings were that the distal centralizer and distal part of the stem shifted to the cortex in 7 hips and bent or failed at the inserted site in 2 hips. There is risk of generating a thin cement mantle with use of the triangular centralizer and its insertion into the stem tip.

Adult↗
PubMed2001

Anatomical relationship between arteries and veins in the scapular region.

Veins in the scapular region were investigated in five fresh cadavers, in which radiopaque materials were injected into both the arterial and the venous systems, to determine their locational relationship to the arteries. This radiographic technique is very useful for comparing veins and arteries. Many veins not accompanying arteries were observed, and veins in the skin and subcutaneous tissue were considered to consist of venae comitantes and non-venae-comitantes. The non-venae-comitantes formed a mainly polygonal venous network in the skin layer, and large communicating veins connected the venous network to the scapular or parascapular veins. These veins played a role in the drainage of venous blood that had perfused the dermis and, in this sense, they should be named cutaneous veins.

Angiography↗
PubMed2001

The treatment of skull base meningiomas--combining surgery and radiosurgery.

While the operative results for treating skull base meningiomas have improved due to modern microsurgical techniques, surgery is still accompanied by a high morbidity rate. Over the last 6 years, we operated on 50 patients with intracranial meningiomas, 23 of which were skull-based lesions. Among these patients with skull base meningiomas, seven (30%) were treated with both surgery and radiosurgery. All patients received standard operative procedures. Five patients received subtotal resections and two patients received partial resections. No mortalities occurred in our series. Following the operations, the clinical status improved in six patients, while only one patient (with a tuberculum sellae meningioma) experienced deterioration of a preexisting visual disturbance. Radiosurgery was performed at a mean of 4.3 months after the operations. One patient was treated by a two-staged radiosurgery regimen in light of the patient's large tumour volume (57.5 cm(3)). The treatment volume of the series ranged from 0.3 to 29.6 cm(3)(mean 11.6 cm(3)), and the minimum dose for the tumours was from 8 Gy to 12 Gy (mean, 11.6 Gy). Tumour regression was observed in three patients (43%) during the follow up period for radiosurgery (mean: 28 months). No patients revealed tumour growth in the follow up period or suffered symptomatic radiation injury. The clinical status remained unchanged in each of the seven patients after radiosurgery. Although we treated only seven patients with skull base meningiomas using surgery combined with radiosurgery, and the follow up period has been short, we believe that such combination treatment may be a very useful option in selected patients.

Adult↗
PubMed2001

Increase of dendritic cells of type 2 (DC2) by altered response to IL-4 in atopic patients.

BACKGROUND: Recent studies have shown that there are 2 dendritic cell subpopulations, DC1 and DC2, which induce T(H)1 and T(H)2 cell differentiation in vitro, respectively. OBJECTIVE: The purpose of this study was to determine whether there exists a deviation of DC1 and DC2 subsets and to investigate their functional abnormalities in T(H)2 cell-mediated atopic diseases. METHODS: We analyzed the frequencies of DC1 (CD11c(+)CD123(-)) and DC2 (CD11c(-)CD123(+)) cells in peripheral blood of atopic patients; we also studied the responses of DC2 cells from atopic patients to IL-3 and IL-4 for their survival. RESULTS: DC2 cells but not DC1 cells were significantly increased in peripheral blood of atopic patients in comparison with that of healthy subjects. DC2 cell numbers were positively correlated with serum IgE levels and blood eosinophil counts, the increase of which reflects T(H)2-type immune response in atopic diseases. IL-4 inhibited IL-3-induced survival of DC2 cells from healthy controls, but IL-4 failed to suppress the IL-3-induced survival of DC2 cells from atopic patients. Furthermore, IL-4 alone enhanced the survival of DC2 cells from atopic patients but not from healthy controls. However, no significant differences were found in the expression levels of activation/maturation markers on DC2 cells between atopic patients and healthy controls. CONCLUSION: These results indicate that DC2 cells are preferentially increased in atopic patients in correlation with the state of atopic allergy and that DC2 cells in atopic patients, unlike those in healthy subjects, exhibit altered responses to IL-4 for survival, suggesting that DC2 cells in atopic patients might contribute to the enhanced T(H)2 cell differentiation in atopic diseases.

Adult↗
PubMed2001

Recent advances in the pathology of alcoholic myopathy.

This article represents the proceedings of a symposium at the 2000 ISBRA Meeting in Yokohama, Japan. The chairs were Victor R. Preedy and Junko Adachi. The presentations were (1) Alcoholic myopathy: Past, present and future, by Timothy J. Peters and Victor R. Preedy; (2) Protein adducts in the type I and II fiber-predominant muscles of the ethanol-fed rat, by Simon Worrall, Seppo Parkkila, and Onni Niemela; (3) Hydroperoxides and changes in alcoholic myopathy, by Junko Adachi, Migiwa Asamo, and Yasuhino Ueno; and (4) A close association between testicular atrophy, muscle atrophy, and the increase in protein catabolism after chronic ethanol administration, by Kunihiko Takeda, Masayoshi Yamauchi, Kazuhiko Sakamoto, Masaru Takagi, Hisato Nakajima, and Gotaro Toda.

Alcoholism↗
PubMed2001

Clinicopathologic and immunohistochemical features and microsatellite status of endometrial cancer of the uterine isthmus.

To clarify the clinicopathologic, molecular, and immunohistochemical characteristics of uterine isthmic endometrial cancer (UIE), we examined 13 cases of UIE and compared them with 33 cases of endometrial cancer of the uterine corpus (UCE) with respect to clinicopathologic factors, the expression of p53, the estrogen receptor (ER) and the progesterone receptor (PR) status, DNA ploidy, and microsatellite instability (MSI). Five (38.4%) of the UIE patients had stage I, two (15.4%) had stage II, and six (46.2%) had stage III disease (FIGO 1988). Myometrial invasion was confirmed in 92.3% of the UIE patients, and these patients had a higher (p < 0.05) frequency of > 50% myometrial invasion (46.2%) than the patients with UCE (15.2%). Moreover, the UIE patients had a higher frequency of positive peritoneal cytology (p < 0.05) and pelvic lymph node metastases (p < 0.05). No UIE tumors exhibited MSI, and the tumors in these patients had a higher expression of p53 (p < 0.01), a lower expression of ER (p < 0.05) and PR (p < 0.05), and a higher frequency of DNA aneuploidy (p < 0.01) than the UCE tumors. These findings suggest that the UIE is clearly different from UCE in the clinicopathologic, immunohistochemical features, and microsatellite status.

Aneuploidy↗