Search PubMed⌕ Search

Biomedical subjects

F Nakajima

Publications and source records attributed to F Nakajima.

At least 37 records · Page 2Linked to original sources
PubMed2001

Aeration conditions affecting growth of purple nonsulfur bacteria in an organic wastewater treatment process.

Effects of aeration on purple nonsulfur bacteria (PnSB) were studied in photobioreactors. Bacterial community changes were analyzed by denaturing gradient gel electrophoresis (DGGE) and fluorescence in situ hybridization (FISH). DGGE band pattern change was small and only few prominent bands were obtained at non-aeration condition. Sequencing results of the prominent DGGE bands obtained at this condition revealed that they represented mainly the PnSB, Rhodobacter sphaeroides and Rhodopseudomonas palustris. On the other hand, under aerated condition, some prominent bands originated from heterotrophs appeared but no proliferation of PnSB was observed. FISH was applied to detect PnSB and their population was quantified. Maximum PnSB ratio (up to 80%) was obtained both at non-aeration condition and at constant ORPs less than -200 mV. In the presence of DO, Rps. palustris was more competitive to chemoheterotrophs than Rb. sphaeroides.

Bioreactors↗
PubMed2001

A novel experimental mouse model of peritoneal dissemination of human gastric cancer cells: analysis of the mechanism of peritoneal dissemination using cDNA macroarrays.

We established a new cell line, NUGC-3P4T, with high peritoneal metastatic disseminating potential in nude mice. NUGC-3P4T cells were derived from the human gastric carcinoma line NUGC-3, which has low capacity for peritoneal dissemination. NUGC-3P4T cells developed peritoneal dissemination in 10 / 10 (100%) mice, whereas the parental NUGC-3 cells developed dissemination in 1 / 5 (20.0%) mice. The metastatic foci in the peritoneum showed essentially the same histological appearance as those induced by parental cells. The tumorigenicity, the motile activity and the adhesive activity to the laminin of NUGC-3P4T cells were stronger than those of NUGC-3 cells. Production of IL-8 was significantly higher in NUGC-3P4T than in NUGC-3. cDNA macroarrays analysis showed that a variety of cytokines, interleukins, and other immunomodulators and their receptors were up- or down-regulated at the mRNA level in NUGC-3P4T cells, compared with NUGC-3 cells. Thus, this unique cell line and in vivo model might be useful to study the biology of peritoneal dissemination of human gastric cancer.

Animals↗
PubMed2001

Potential fascial dome made by the upper leaf of the phreno-esophageal membrane.

We describe the configuration and size of the artificial fascial dome created in 57 cadavers. This dome protrudes into the thoracic cavity from the esophageal hiatus. This dome was a potential space realized by finger dissection (i.e., a specific but common surgical procedure during surgery of the upper part of the stomach). The vagus nerves penetrated the top of the dome and ran down along the esophagus. The height of the ventral wall of the dome ranged from 10-60 mm, while the dorsal wall was 10-40 mm longer than the ventral one since the dorsal wall attached to the lower, dorsal limb of the esophageal hiatus. Accordingly, the dorsal wall separated the "thoracic" aorta from the "abdominal" esophagus. We considered that the upper leaf of the phreno-esophageal membrane forms the fascial dome, although the lower leaf of the membrane was not identified in this study. According to the results, we proposed a schematic representation of the phreno-esophageal membrane.

Aged↗
PubMed2001

[Relationship between hyperglycemia following head injury and neurological outcome].

Severe head injury is associated with a stress response that includes hyperglycemia, which has been shown in both experimental and clinical studies to exacerbate the severity of brain injury during ischemic conditions. To define the relationship between serum glucose levels and the outcome of patients suffering from closed head injury, we retrospectively reviewed the clinical courses of 88 consecutive head-injured patients. The patients were divided into two groups according to their GCS score on admission: severely head-injured group (GCS score of 8 or less) in 36 patients; moderately head-injured group (GCS score of 9 to 12) in 52 patients. Severely head-injured group had significantly higher serum glucose levels than moderately head-injured group (mean +/- standard error of the mean; 201 +/- 4.6 mg/dl vs. 171.4 +/- 3.8 mg/dl) (p < 0.01). Patients who subsequently resulted in severe disability, vegetative state, or death had significantly higher serum glucose levels than patients who had good recovery or moderate disability (204.9 +/- 5.9 mg/dl vs. 162.9 +/- 5.1 mg/dl) (p < 0.01). Cases with a fatal clinical course were mostly associated with high glucose levels. All patients who showed a serum glucose level greater than 240 mg/dl on admission were dead. These data suggest that the hyperglycemia on admission is a frequent component of the stress response to head injury, a significant indicator of severity of injury and a potent predictor of the outcome from head injury.

Adolescent↗
PubMed2001

Adenosquamous carcinoma of the colorectum: report of two cases.

Adenosquamous carcinomas of the colorectum are rare neoplasms. Our experience with two cases is presented in this paper. One patient, who complained of bloody stool, was found to have adenocarcinoma in the sigmoid colon. He received a laparoscopy-assisted sigmoidectomy. The histological examination revealed that the tumor was adenosquamous carcinoma. To date, he has survived six months post operatively without evidence of recurrence. The other patient, who complained of anal bleeding, was found to have rectal adenocarcinoma and received a low anterior resection. Histological examination revealed that the tumor was an adenosquamous carcinoma. He remains alive, with no evidence of recurrence, nine years post operatively. Both cases showed paracolic lymph node metastasis. Because of its very low incidence, the histogenesis, malignancy and prognosis of this disease remain unclear. Thus, further clinical and histological study of this disease entity is required.

Carcinoma, Adenosquamous↗
PubMed2000

Design of fluorogenic substrates for continuous assay of sialyltransferase by resonance energy transfer.

Glycosyltransferases are important synthetic enzymes for the construction of naturally occurring glycoconjugates as well as for the design of neoglycoconjugates. The assay methods currently available for these enzymes require tedious and time-consuming procedures for separation of products and do not permit continual assay of enzyme activities. As a set of convenient fluorogenic substrates for continuous monitoring of sialyltransferase activities, we designed and synthesized a novel CMP-Neu5Ac derivative with a naphthylmethyl group at the C-9 position and N-acetyllactosamine derivative containing a dansyl group at the terminal position of aglycon. In such substrates, the emission peak of the naphthylmethyl group (lambdaem = 340 nm) of the glycosyl donor is successfully overlapped with the excitation peak due to the dansyl group (lambdaex = 335 nm) of the glycosyl acceptor. A coupling reaction of these two substrates catalyzed by rat liver 2,6-sialyltransferase caused an increase of dansyl fluorescence (lambdaem = 525 nm) and a decrease of naphthylmethyl fluorescence on the basis of resonance energy transfer between two fluorescence probes. The substrates presented here permit continuous fluorescent monitoring of enzymatic sugar combining reactions. Actually, using this time course of enzymatic reactions, kinetic constants of rat liver 2,6-sialyltransferase against glycosyl donor substrates were estimated to be Km = 4.85 microM and Vmax. = 0.119 micromol/min, respectively. This strategy allows precise and efficient analyses of enzyme kinetics not possible with the conventional assay methods for the glycosyltransferases that usually require separation of products from the reaction mixture.

Alkaline Phosphatase↗
PubMed2000

Ruptured cerebral aneurysm not detected by magnetic resonance angiography in juvenile autosomal dominant polycystic kidney.

Recently, it has been reported that magnetic resonance angiography (MRA) is useful for screening and following up cerebral aneurysms in patients with autosomal dominant polycystic kidney disease (ADPKD). However, a patient was encountered with a ruptured cerebral aneurysm that was not detected by routine MRA. The patient, a 29-year-old man with ADPKD, was followed up at our hospital for more than 5 years. Ten months after an MRA examination, he suddenly developed severe headache. Brain computed tomography revealed subarachnoid hemorrhage. Digital subtraction angiography detected an aneurysm with a diameter of approximately 2 mm in the anterior communicating artery. Clipping of the aneurysm was immediately performed and he recovered without sequela after operation. Magnetic resonance angiography is useful to detect cerebral aneurysms, but it can not detect aneurysms measuring less than 4 mm.

Adult↗
PubMed2000

The influence of HLA genotyping compatibility on clinical outcome after cord blood transplantation from unrelated donors.

We performed retrospective DNA typing of class I (A, B, Cw) and class II (DRB1, DQB1, DPB1) HLA alleles in 27 unrelated cord blood transplantation (CBT) cases donated from a single cord blood bank (Kanagawa Cord Blood Bank). The influence of HLA genotype matching on clinical outcome was evaluated. From Cox's model, we found that incompatibility of two or more HLA alleles between the donor and recipient of an unrelated CBT was suggested to be a risk factor for a worse event-free survival (EFS) (p = 0.04; RR, 4.06; 95% CI, 1.06-15.61). Furthermore, mismatches including HLA-DRB1 alleles had an adverse effect on EFS (p = 0.04; RR, 4.91; 95% CI, 1.01-24.02). For definite conclusions on the role of HLA allele typing in unrelated CBT, more accumulation of data and analysis will be required.

Actuarial Analysis↗
PubMed2000

Intracranial aneurysms and autosomal dominant polycystic kidney disease: followup study by magnetic resonance angiography.

PURPOSE: Intracranial aneurysms are known to complicate autosomal dominant polycystic kidney disease. We assess the value of magnetic resonance angiography to detect intracranial aneurysms early in patients with autosomal dominant polycystic kidney disease. MATERIALS AND METHODS: We evaluated 15 patients with asymptomatic autosomal dominant polycystic kidney disease treated at our hospital between 1992 and 1998. Magnetic resonance angiography was performed at presentation and was repeated 18 to 72 months after treatment. RESULTS: On the initial magnetic resonance angiogram 3 intracranial aneurysms were detected in 3 patients. The intracranial aneurysms ranged from 4 to 8 mm. in diameter, and were in the anterior communicating artery in 1, in the vertebral artery in 1, and at the bifurcation of the internal carotid artery and ophthalmic artery in 1 case. Repeat magnetic resonance angiography 18 to 72 months after treatment revealed new intracranial aneurysms in 2 patients. In 1 case the lesion was 7 mm. in diameter, in the internal carotid artery and posterior communicating artery, and detected 69 months after the initial angiogram. In the other patient the lesion was 4 mm. in diameter, in the anterior communicating artery and detected 71 months after treatment. CONCLUSIONS: Since new intracranial aneurysms were demonstrated in patients followed for a long time periodic repeat magnetic resonance angiography is important.

Adult↗
PubMed1999

Distribution of gamma-tubulin in multipolar spindles and multinucleated cells induced by dimethylarsinic acid, a methylated derivative of inorganic arsenics, in Chinese hamster V79 cells.

Localization of gamma-tubulin, a well-characterized component of microtubule-organizing centers (MTOCs), was investigated because of interest in the mechanism of the induction of aberrant mitotic spindles in Chinese hamster V79 cells exposed to dimethylarsinic acid (DMAA). In control cultures, gamma-tubulin in interphase cells was located as a perinuclear dot on which the microtubules were nucleated. In metaphase cells, the location of gamma-tubulin coincided with that of the mitotic spindle poles. DMAA caused mitotic delay and aberrant spindles, such as tripolar- and quadripolar spindles, in the mitotic cells. Gamma-tubulin was co-localized with the aberrant spindles induced by DMAA. The incidence of gamma-tubulin in the mitotic cells coincided with that of the aberrant spindles and rose with an increasing concentration of DMAA. By contrast, DMAA did not influence the number and location of gamma-tubulin signals in interphase cells. These results suggest that multiple microtubule nucleation sites were induced by DMAA during transition from interphase to mitotic phase. DMAA-induced multiple signals of gamma-tubulin were integrated into one signal at the center of multinucleated cells, surrounded by multiple nuclei as the cell cycle progressed to the next interphase, suggesting the presence of a self-integration mechanism of centrosomal MTOCs during the cell cycle.

Animals↗
PubMed1999

Spatial and temporal distribution of CD44 and osteopontin in fracture callus.

The multifunctional adhesion molecule CD44 is a major cell-surface receptor for hyaluronic acid (HUA). Recent data suggest that it may also bind the ubiquitous bone-matrix protein, osteopontin (OPN). Because OPN has been shown to be a potentially important protein in bone remodelling, we investigated the hypothesis that OPN interactions with the CD44 receptor on bone cells participate in the regulation of the healing of fractures. We examined the spatial and temporal patterns of expression of OPN and CD44 in healing fractures of rat femora by in situ hybridisation and immunohistochemistry. We also localised HUA in the fracture callus using biotinylated HUA-binding protein. OPN was expressed in remodelling areas of the hard callus and was found in osteocytes, osteoclasts and osteoprogenitor cells, but not in cuboidal osteoblasts which were otherwise shown to express osteocalcin. The OPN signal in osteocytes was not uniformly distributed, but was restricted to specific regions near sites where OPN mRNA-positive osteoclasts were attached to bone surfaces. In the remodelling callus, intense immunostaining for CD44 was detected in osteocyte lacunae, along canaliculi, and on the basolateral plasma membrane of osteoclasts, but not in the cuboidal osteoblasts. HUA staining was detected in fibrous tissues but little was observed in areas of hard callus where bone remodelling was progressing. Our findings suggest that OPN, rather than HUA, is the major ligand for CD44 on bone cells in the remodelling phase of healing of fractures. They also raise the possibility that such interactions may be involved in the communication of osteocytes with each other and with osteoclasts on bone surfaces. The interactions between CD44 and OPN may have important clinical implications in the repair of skeletal tissues.

Animals↗
PubMed1999

[A patient of successful renal transplantation using donor kidney with congenital abnormalities of the inferior vena cava].

At the time of donor nephrectomy, congenital abnormalities of the inferior vena cava was discovered. A 56-year-old woman was worked up preoperatively and no abnormalities were found. Abdominal aortography was normal. At the time of operation, the inferior vena cava was located to the left and anterior to the abdominal aorta. In the renal hilus, the location of the renal artery and vein was reversal. We thought the ideas of operation and could successfully performed renal transplantation using donor kidney with congenital abnormalities of the inferior vena cava.

Female↗
PubMed1999

[A clinical study of recurrence and progression of grade 3 superficial bladder tumor].

Forty-one patients who had grade 3, superficial, transitional cell carcinoma of the bladder were treated with transurethral resection of bladder tumor between January, 1986 and April, 1998. The clinicopathological studies were conducted on intravesical recurrence, disease progression, and prognosis using multivariate analyses. Intravesical recurrence was found in 18 patients (43.9%), and the recurrence-free rate was 77.0% for 1 year. The 3- and 5-year recurrence-free rates were 57.7% and 38.5% for patients with stage pTa disease, and 36.3% and 36.3% for patients with stawe pT1-disease. There was a significant difference between the recurrence-free rates in the patients with stage pTa disease and those with stage pT1 disease (p < 0.01). Disease progression was observed after a mean period of 14.2 months after treatment in 6 patients (14.6%) with pT1 tumors. Three of these patients died of cancer. In the multivariate analyses with clinical and pathological factors, bladder irritability, urine cytology after initial treatment, and tumor multiplicity were the factors contributing to a high risk for recurrence. Intravesical instillation with Calmette-Guerin bacillus was found to prevent recurrence. These results suggest that radical surgery should be performed in a timely manner in patients with G3-stage pT1 tumors because they have a higher risk of recurrence and progression as compared to patients with G3-stage pTa tumors.

Administration, Intravesical↗
PubMed1999

[A fistula between the common iliac artery and ureter following cutaneous ureterostomy: a case report].

A 72-year-old man underwent total cystectomy with single stoma cutaneous ureterostomy for the treatment of transitional cell carcinoma of the bladder. The patient came to the outpatient clinic every 2 weeks to exchange ureteral catheters. Six months after the operation, he was admitted to our hospital again due to edema of bilateral legs, fever, and loss of appetite. The patient had metastasis of intrapelvic and paraaortic lymph nodes associated with cachexia, and was given intravenous hyperalimentation and treatment to control pain. Suddenly, he complained of left flank pain. When the ureteral catheter was removed, massive bleeding occurred from the stomal orifice. A fistula between the artery and ureter was suspected. Six days later, the patient died due to acute renal failure. After his death, retrograde ureterography was performed to confirm the fistula. A fistula was found between the left common iliac artery and left ureter.

Aged↗
PubMed1998

Different effects of inorganic and dimethylated arsenic compounds on cell morphology, cytoskeletal organization, and DNA synthesis in cultured Chinese hamster V79 cells.

Changes in cytoskeletal organization of cultured V79 cells exposed to arsenite and dimethylarsinic acid (DMAA), a methylated derivative of inorganic arsenics, and related changes, such as mitotic arrest and induction of multinucleated cells, were investigated in comparison with their effects on DNA synthesis. DMAA caused mitotic arrest and induction of multinucleated cells with a delay of 12 h relative to the mitotic arrest. By contrast, arsenite at equitoxic concentrations to DMAA was less effective than DMAA in causing mitotic arrest and in inducing multinucleated cells. Post-mitotic incubation of cells arrested in metaphase by 6 h incubation with 10 mM DMAA showed that the incidence of multinucleated cells increased conversely with a rapid decrease in metaphase cells. This suggests that metaphase-arrested cells can escape from metaphase, resulting in the appearance of multinucleated cells. The mitotic arrest caused by DMAA was accompanied by disruption of the microtubule network. By contrast, both arsenite and DMAA did not cause disorganization of actin stress fibers even when incubated at concentrations that caused a marked retardation of cell growth. Cells exposed to arsenite for 6 h showed marked inhibition of DNA synthesis, whereas inhibition by DMAA was not observed. When incubation was prolonged by 18 h, the arsenite-induced inhibition of DNA synthesis was mitigated. By contrast, inhibition of DNA synthesis by DMAA occurred in parallel with an increase in the population of mitotic cells. These results suggest that DMAA caused growth retardation and morphological changes via disruption of the microtubule network, and that arsenite-induced retardation of cell growth and inhibition of DNA synthesis were not attributable to the cytoskeletal changes.

Animals↗