Search PubMed⌕ Search

Biomedical subjects

K Kuroda

Publications and source records attributed to K Kuroda.

At least 199 records · Page 11Linked to original sources

Dysautoregulation in patients with hypertensive intracerebral hemorrhage. A SPECT study.

In patients with hypertensive intracerebral hemorrhage, changes in regional cerebral blood flow (rCBF) following drug-induced blood pressure reduction were examined by SPECT. METHODS. The subjects were 68 patients with hypertensive intracerebral hemorrhage. The site of cerebral hemorrhage was the thalamus in 28 patients, and the putamen in 40 patients. RCBF was measured by SPECT using the 133Xe inhalation method. To reduce blood pressure, trimethaphan camsilate (an autonomic ganglion blocker) and diltiazem hydrochloride (a calcium antagonist) were used. RESULTS. 1. In the acute period, mean CBF declined as the mean arterial blood pressure declined by more than 20% in both the putaminal and the thalamic hemorrhage group (p < 0.01). 2. During the chronic period, a greater reduction in blood pressure was needed to induce mean CBF reduction. 3. Neither of the two drugs significantly reduced the mean arterial blood pressure, but the group receiving trimethaphan demonstrated a 7.9 approximately 7.5% decreased in CBF, group while the receiving diltiazem showed a 2.2 approximately 2.4% decrease (p < 0.05). CONCLUSIONS. In patients with hypertensive intracerebral hemorrhage, a 20% or more drug-induced decrease in blood pressure resulted in a decrease in mean CBF. During the acute period of intracerebral hemorrhage, blood pressure showed reduced by 20%. Clinically, diltiazem was more effective than trimethaphan.

Adult↗

Identification of Kk-restricted T-cell epitope within influenza virus nucleoprotein.

In order to determine the epitope structure in peptide NP50-63, which has been reported to be the only Kk-restricted T-cell antigen within the influenza virus (A/PR/8/34) nucleoprotein, a series of 13 peptides truncated from C- and N-termini of NP50-63 were synthesized and their sensitizing activities against Kk-restricted nucleoprotein-specific cytotoxic T lymphocytes (CTLs) were examined. One of the 13 peptides, NP50-57, sensitized L929 cells at the nM level, which was 100-1000 times lower in concentration than that at which the other peptides sensitized these cells. The presence of NP50-57 in A/PR/8/34-infected L929 cells was also investigated. Acid extracts of virus-infected cells were separated on a reverse-phase HPLC column and then anion-exchange column. By both separations, only one peak of sensitizing activity against nucleoprotein-specific CTLs was observed. The position of the peak coincided with that of the elution of NP50-57. These results strongly suggest that NP50-57 is the natural epitope in the antigenic structure, NP50-63.

Amino Acid Sequence↗

Expression patterns of DNA replication enzymes and the regulatory factor DREF during Drosophila development analyzed with specific antibodies.

Specific antibodies were prepared against Drosophila DNA polymerase epsilon and DREF, a regulatory factor for DNA replication-related genes. Using these antibodies together with those for DNA polymerase alpha and proliferating cell nuclear antigen (PCNA), we examined expression patterns and sub-cellular distributions of these proteins during Drosophila development. DNA polymerase alpha, epsilon and PCNA proteins were maternally stored in unfertilized eggs and maintained at high levels during embryogenesis. With distinct nuclear localization, proteins were observed in embryos at interphase stages throughout the 13 nuclear division cycles, suggesting that they all participate in rapid nuclear DNA replication during these cycles. In contrast, maternal storage of a DREF protein was relatively low and its level increased throughout embryogenesis. Strong nuclear staining with the anti-DREF antibody was not observed until the nuclear division cycle 8. Immunostaining of various larval tissues from transgenic flies carrying the PCNA gene promoter-lacZ fusion gene revealed co-expression of DREF, PCNA and lacZ, suggesting that DREF regulates the expression of PCNA gene in these tissues. In addition, we detected a relatively high level of DREF in adult males as well as females. Since DNA polymerase alpha, epsilon and PCNA are hardly detectable in adult males, DREF very likely regulates genes other than those closely linked to DNA replication in adult males.

Animals↗

Overcoming the metastasis-enhancing potential of human tumor necrosis factor alpha by introducing the cell-adhesive Arg-Gly-Asp sequence.

A mutein, F4168, of human tumor necrosis factor alpha (hTNF-alpha) containing the cell-adhesive Arg-Gly-Asp (RGD) sequence near the N terminus was constructed. In contrast to hTNF-alpha, the mutein had binding activity to B16F10/L5 melanoma cells similar to that of fibronectin or laminin, indicating that the adhesive nature of the RGD sequence is conferred upon hTNF-alpha. Introduction of the RGD sequence did not alter the antitumor potential of hTNF-alpha. Simultaneous injection of F4168 and B16F10/L5 melanoma cells into mice did not enhance metastasis formation in lungs, whereas hTNF-alpha significantly promoted it. Enhancement of spontaneous lymph node metastasis of B16F10/L5 cells was also evident in TNF-alpha- but not in F4168-treated mice. In the spontaneous lymph node metastasis model of MethA fibrosarcoma, F4168 injection inhibited metastasis formation more effectively than hTNF-alpha. B16F10/L5 melanoma cells treated with hTNF-alpha enhanced not only their binding activity to laminin but also their invasive potential into Matrigel, whereas F4168 showed no such enhancement. These results suggest that F4168 is a low-toxicity mutein of hTNF-alpha.

Amino Acid Sequence↗

Novel mutein of tumor necrosis factor alpha (F4614) with reduced hypotensive effect.

To eliminate systemic toxicity, including the hypotension associated with human tumor necrosis factor alpha (TNF-alpha), we constructed mutant proteins (muteins) by mean of genetic engineering. A novel mutein, F4614, containing mutations of 5Thr-->Gly and 6Pro-->Asp, which resulted in the introduction of cell-adhesive Arg-Gly-Asp and 29Arg-->Val, had remarkably reduced hypotensive effects and lower lethality. We present evidence that the Arg-->Val mutation at position 29 is largely responsible for the reduced hypotensive effect. This effect of F4614 was thought to be closely correlated with its low inducibility of nitric oxide and prostaglandin E2 in vivo. In addition, the therapeutically effective dose of F4614 to MethA fibrosarcoma-transplanted mice was increased compared with that of TNF-alpha, indicating a wide therapeutic index. These results indicated that F4614 has several advantages as a systemic therapeutic drug in the treatment of cancer.

Amino Acid Sequence↗

A 130 kDa polypeptide immunologically related to the 180 kDa catalytic subunit of DNA polymerase alpha-primase complex is detected in early embryos of Drosophila.

An immunocytochemical method using specific antibodies was employed to detect DNA polymerase alpha-primase complex in Drosophila melanogaster embryos during the first 13 nuclear division cycles. A monoclonal antibody specific to the 72 kDa polypeptide stained interphase nuclei, but not metaphase chromosome, while at late anaphase and thereafter staining of the chromosome was regained. On the other hand, a polyclonal antibody specific to the 180 kDa polypeptide stained not only the interphase nuclei but also the cytoplasmic regions surrounding interphase nuclei. These results suggest that the distributions of the 180 kDa and the 72 kDa polypeptides of DNA polymerase alpha-primase complex are different. We detected the 180 kDa and the 72 kDa polypeptides in the extract prepared from a single Drosophila embryo by Western blotting, and a 130 kDa polypeptide immunologically related to the 180 kDa polypeptide was also detected in the extract. These polypeptides (180, 130, and 72 kDa) in the embryos were detected at similar levels at interphase and at the mitotic phase. These three polypeptides were also detected in unfertilized eggs, showing that they were maternally stored. The 130 kDa polypeptide was detected till cycle 10, then began to decrease, and finally disappeared at cycle 14, whereas the 180 kDa and the 72 kDa polypeptides were present without marked fluctuation in quantity throughout the developmental stages. Even in unfertilized eggs, the level of the 130 kDa polypeptide decreased gradually with a similar time course to that in fertilized ones, but the levels of the 180 kDa and the 72 kDa polypeptides remained unchanged. This is the first report suggesting the existence of the 130 kDa polypeptide in vivo in the early embryos of Drosophila. The significance of the 130 kDa polypeptide is discussed.

Amino Acid Sequence↗

Pustular psoriasis precipitated by acetazolamide.

We report a case of pustular psoriasis precipitated by acetazolamide, a carbonic anhydrase inhibitor. A 28-year-old man suffering from 20 years-standing generalized pustular psoriasis developed psoriatic arthritis and glaucoma and experienced a precipitation of pustular lesions and widespread erythema after initiation of oral acetazolamide for glaucoma. The cutaneous lesions and systemic symptoms improved after restriction of acetazolamide and administration of oral etretinate. Readministration of acetazolamide confirmed that generalized pustules arose within 24 hours.

Acetazolamide↗

A case of pretibial myxedema associated with Graves' disease: an immunohistochemical study of serum-derived hyaluronan-associated protein.

The myxomatous materials in cutis from a patient with pretibial myxedema (PTM) with Graves' disease were found to be mainly hyaluronic acid (HA), which had accumulated extensively in the upper dermis. Fibroblasts were increased in number in the mid to lower dermis. To clarify the mechanism of the deposition of HA in the dermis, we employed an antibody against serum-derived hyaluronan-associated protein (SHAP). This immunohistochemical study disclosed that the greater part of the fibroblasts in the mid to lower dermis stained positively, while the fibroblasts surrounded by fairly large amounts of HA in the upper dermis stained faintly or not at all. From these results, we suspect that the accumulation of HA progresses from the upper to the low dermis and that the interaction of fibroblasts and SHAP leads to development of the physiophathological cutaneous changes seen in our case.

Fibroblasts↗

Unusual cutaneous manifestations of myelodysplastic syndrome.

We report a 58-year-old patient with acute myeloid leukaemia who developed an oedematous erythema resembling Sweet's syndrome, accompanied by atypical erythema nodosum and bullous pyoderma gangrenosum. Examination of skin biopsies showed dense infiltration with mature neutrophils, although there was peripheral blood leucocytopenia. The oedematous erythema worsened after he was treated with granulocyte-colony-stimulating factor (G-CSF), which was given for his leucocytopenia. We suggest that when a neutrophilic dermatosis complicates leukaemia, alternatives to G-CSF should be considered for the treatment of leucocytopenia. Corticosteroids were very effective in controlling the skin lesions in our patient.

Acute Disease↗

Adsorption of saliva-coated and just-harvested Streptococcus sanguis to saliva-coated hydroxyapatite beads.

It is possible that salivary proteins on bacterial cells have some influence on the adsorption of oral bacteria to the surface of oral tissues. The aim of this study was to clarify the influence of salivary proteins attached to the surface of Streptococcus sanguis ATCC 10556 (S. sanguis) on bacterial adsorption to hydroxyapatite beads treated with salivary proteins (S-HA beads). Just-harvested cells (N-system) and saliva-coated cells (C-system) were used. The results showed that adsorption to S-HA beads was gradually reduced by a covering of salivary proteins. No influence was observed on the adsorption of cells due to the presence of divalent cations, phosphate or EDTA when the N-system and C-system were compared. Though it was evident that hydrophobic bonding was involved in adsorption in the N-system, few such effects were observed in the C-system. Adsorption was inhibited to varying degrees by sugars in both systems. Pretreatment of cells with heat affected adsorption differently in the N-system and C-system. These findings suggest that salivary proteins attached to the bacterial cell surface may influence its adsorption to oral tissues.

Adsorption↗

[A case of bilateral thoracoscopic partial resection for unilateral spontaneous pneumothorax].

There is a high incidence of pneumothorax on the contralateral side in patients with unilateral spontaneous pneumothorax. This is because bullae and blebs of the lungs, the cause of this condition, are frequently present bilaterally. Recently, thoracoscopic partial lung resection has become more common and has been proven to have advantages such as less bleeding, less pain and a smaller skin incision. In view of the common occurrence of contralateral pneumothorax, bilateral simultaneous thoracoscopic partial lung resection for unilateral spontaneous pneumothorax is recommended for patients in their teens and twenties who have contralateral bullae and blebs.

Adolescent↗

[Prognostic predictors in colorectal cancer].

The prognostic significance of clinicopathologic factors in colorectal cancer was evaluated in a multivariate analysis. The most important independent factor affecting survival was stage (depth of penetration through the bowel wall and the presence of positive lymph nodes). All other clinicopathologic factors were of less importance than stage in determining prognosis. Although the prognostic relevance of biologic and molecular variables has been investigated extensively, the importance of these factors as prognostic predictors remains uncertain and further studies are needed.

Colorectal Neoplasms↗

[Pulmonary actinomycosis presenting as a mass shadow with a cavity on chest radiography].

A 53-year-old woman was admitted with diabetes mellitus. After admission, a tumor shadow was detected by chest radiography and blood was found in her sputum. Despite further investigations, no definite diagnosis was made. Pulmonary wedge resection was performed because malignancy could not be excluded. Histological examination of the resected lung specimen led to the diagnosis of pulmonary actinomycosis. In Japan, 59 cases of pulmonary actinomycosis were reported between 1964 and 1993. These reports indicate that many cases of this disease are diagnosed by histological examination of resected lung specimens. Pulmonary actinomycosis has become even rarer recently because of the development of chemotherapy. We report this case and discuss the relevant literature.

Actinomycosis↗

[A case of carpal tunnel syndrome caused by a ganglion cyst--diagnosis and follow-up study with magnetic resonance imaging].

We report a case of carpal tunnel syndrome (CTS) caused by a ganglion cyst which was diagnosed by magnetic resonance (MR) imaging of the left wrist. MR images depicted a 10-mm ganglion cyst which pressed the median nerve toward the ulnar side. The ganglion cyst was punctured under direct endoscopic visualization in the carpal canal, subsequently the clinical and the electrophysiologic findings of CTS improved. The median nerve was delineated in its proper position. MR imaging of the wrist, a noninvasive means to observe median nerve, is useful for the diagnosis and the follow-up study of CTS.

Adult↗

Characterization of defectiveness in endogenous antigen presentation of novel murine cells established from methylcholanthrene-induced fibrosarcomas.

Three cell lines (4A1, 4C2 and 6D1 cells) derived from fibrosarcoma induced by the inoculation of 3-methylcholanthrene into C3H/HeN (H-2k) mice were examined for their ability to present antigens to CD8+ cytotoxic T lymphocytes (CTL). 6D1 and 4C2 cells were deficient in presenting endogenously synthesized influenza virus antigens to CTL, but they were able to present antigens when they were sensitized with a synthetic epitope peptide. The expression of the H-2 Kk gene in 4C2 and 6D1 cells was much reduced and was detectable only with Northern blot hybridization. The expression of two transporter genes (TAP1 and TAP2), examined by Northern hybridization, was also reduced in both cells, and negligible particularly in 4C2 cells. Interferon-gamma (IFN-gamma) treatment of these cells induced expression of Kk, TAP1 and TAP2 genes and rescued the defect of class I-restricted antigen presentation in 4C2 and 6D1 cells. Even after this treatment, however, antigen-presentation capability of 4C2 cells was still much lower than that of normal 4A1 cells. This finding suggests that 4C2 cells might have an additional defective gene(s), whose products are involved in the processing of class I-restricted antigen, besides the Kk and TAP genes, and this may explain the difficulty of 4C2 cells to induce tumour-specific immunity, as described previously. To our knowledge, the 4C2 cell is the first tumour cell postulated to have more than three defective genes involved in class I-restricted antigen presentation.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Identification of Ro(SSA) 52 kDa reactive T cells in labial salivary glands from patients with Sjögren's syndrome.

OBJECTIVE: To identify the self-antigens recognized by autoreactive T cells in labial salivary glands from patients with Sjõgren's syndrome (SS). METHODS: T cells lines were established from infiltrating T cells in the labial salivary glands from 6 patients with SS, using interleukin 2 and phytohemagglutinin. Bulk cultured T cells and T cell lines were examined for the proliferative response to recombinant Ro(SSA) 52 kDa and SSB proteins. The usage of T cell receptor (TCR) V beta and V alpha genes from Ro(SSA) 52kDa reactive T cells was analyzed by family polymerase chain reaction. The sequences of complementary determining region 3 of TCR V beta genes were also examined. RESULTS: Three of 6 bulk cultured T cells and 4 of 16 T cell lines showed a significant proliferative response to Ro(SSA) 52 kDa protein. All T cell lines represented CD4+ alpha beta T cells by flow cytometry analysis. All 4 RO(SSA) 52 kDa reactive T cell lines utilized the V beta 2 gene and 3 lines used the V beta 13 gene, suggesting preferential usage of the V beta 2 and the V beta 13 genes in Ro(SSA) 52 kDa reactive T cells. Junctional sequences of TCR V beta genes from Ro(SSA) 52 kDa reactive T cell lines showed the conserved amino acid sequences in CDR3 region. CONCLUSION: These findings support the notion that Ro(SSA) 52 kDa is a possible autoantigen recognized by autoreactive T cells and that limited epitope is present on the Ro(SSA) 52 kDa antigen.

Amino Acid Sequence↗

A human monoclonal antibody to carbohydrate moiety of carcinoembryonic antigen.

Hybridoma BSRF-S-97, secreting a human monoclonal antibody of IgG1 subclass reactive to the carcinoembryonic antigen, was generated by fusing the regional lymph node lymphocytes from a cervical cancer patient with RF-S1 human-mouse heteromyeloma fusion line. This monoclonal antibody was found specifically reactive to carinoembryonic antigen-producing cell lines, including those of cervical cancer (SKG-II), mucinous type ovarian cancer (RMUG-L), stomach cancer (MKN-45), and lung cancer (PC-10). The monoclonal antibody reactivity with pepsin- and periodate-treated carcinoembryonic antigen demonstrated that this monoclonal antibody recognizes the carbohydrate moiety of carcinoembryonic antigen specifically. Possibilities of the monoclonal antibody reaction with mucin and blood-group antigens were excluded by the comparative studies with a placental mucin-containing protein which reacted with carcinoembryonic antigen-specific rabbit polyclonal antibody. The monoclonal antibody conjugated with Pseudomonas exotoxin showed potent regression effects on the growth of the MKN-45 cell line in both the dish culture and xenografted nude mice, indicating potential usefulness of this human monoclonal antibody as a promising tumor targeting vehicle.

Animals↗