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D Shibata

Publications and source records attributed to D Shibata.

158 records · Page 9Linked to original sources
PubMed1988

Primary structure of soybean lipoxygenase L-2.

The nucleotide sequence of soybean lipoxygenase-2 cDNA has been determined, and the complete amino acid sequence of the enzyme has been deduced. Limited direct amino acid sequence data for lipoxygenase-2 protein support this assignment and exclude mRNA representing lipoxygenase-1 and -3. Lipoxygenase 2 has a molecular weight of 97,036 and contains 865 amino acid residues, in contrast to the isozymes, lipoxygenase-1 and -3, which are known to contain 838 and 859 amino acid residues, respectively. Despite significant differences in behavior between these three isozymes, the amino acid sequences of lipoxygenase-1 and -3 are 81 and 74% identical to lipoxygenase-2, respectively. A region of 40 amino acid residues containing a cluster of six histidines and two tyrosines, which is highly conserved in all three isozymes, is discussed as a possible iron-binding region.

Amino Acid Sequence↗
PubMed1988

Detection of cytomegalovirus DNA in peripheral blood of patients infected with human immunodeficiency virus.

Detection of cytomegalovirus (CMV) DNA can be facilitated by the polymerase chain reaction (PCR), an in vitro gene amplification technique. Twenty-eight CMV tissue culture isolates were examined by amplification of two separate CMV genes. All were found to contain CMV, although two of the isolates were positive for only one of the two genes. No detectable amplification occurred with human genomic or other viral DNA controls. The amplification products from as few as one CMV plaque-forming unit could be detected after the PCR. CMV DNA was detected in the blood of 14 of 27 patients with AIDS and one of six patients who were infected with human immunodeficiency virus but who did not have AIDS. Normal CMV-seropositive or -seronegative individuals did not have CMV DNA detected in their blood. The CMV PCR was more sensitive than the standard culture assay, can be completed in one to two days, uses only 20 microL of blood, and may be useful for rapidly detecting CMV in clinical specimens.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Cytomegalovirus infection in the acquired immunodeficiency syndrome. Clinical and autopsy findings.

The clinical and autopsy findings of cytomegalovirus (CMV) infection in patients with the acquired immunodeficiency syndrome (AIDS) are reviewed. Of 164 patients, 81 had evidence of CMV infection at autopsy, but organ failure leading to patient demise from CMV occurred in only 17. Demographic differences between patients with AIDS with and without CMV were minimal. Cytomegalovirus was never the sole diagnostic criterion for AIDS in any patient but was always accompanied by at least one other opportunistic infection or neoplasm. The total clinical course did not significantly differ between the two groups, but the length of final hospitalization of patients with CMV was much longer. Therapy for CMV prolonged the clinical course in some cases but did not eliminate the infection or prevent death from CMV. At autopsy the most common sites of involvement were adrenal (75%), pulmonary (58%), gastrointestinal (30%), central nervous system (20%), and ocular (10%). Most patients (62%) had multiple sites of involvement. Gross pathologic findings were frequent but often subtle. Microscopic changes accompanying CMV inclusions were variable and usually limited in extent.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Detection of human papillomavirus in normal and dysplastic tissue by the polymerase chain reaction.

Detection of human papilloma virus (HPV) types 16 and 18 in formalin-fixed, paraffin-embedded tissue by a new in vitro DNA amplification method, the polymerase chain reaction, was compared with detection with genomic DNA probes using in situ hybridization. The polymerase chain reaction replicates exponentially HPV DNA sequences present in a single 5- to 10-micron paraffin-embedded tissue section. The amplified sequences are detected with a DNA hybridization probe in a dot blot assay. The HPV polymerase chain reaction was able to detect on the average less than one HPV genome/cell as determined by tests of paraffin sections of cell pellets with known HPV genomic content. Cervical sections from 21 patients with HPV types 16, 18, or 31 as determined by in situ DNA hybridization were analyzed by the polymerase chain reaction. No disagreements between the two methods were detected. The sections comprising normal and dysplastic epithelium were further analyzed by the HPV polymerase chain reaction. The presence of virus correlated with the presence of dysplasia in the sections, though 3 of 10 normal sections contained HPV, and 1 of 21 sections with dysplasia lacked HPV 16 or 18. The polymerase chain reaction can specifically detect HPV 16 or 18 with high sensitivity from paraffin-embedded tissues.

Autoradiography↗
PubMed1987

Primary structure of soybean lipoxygenase-1.

The primary structure of lipoxygenase-1 from soybeans has been determined. The results were deduced from the nucleotide sequence of the complete cDNA for isozyme lipoxygenase-1 and were confirmed by Edman sequencing of selected peptides obtained by CNBr cleavage and supported by carboxyl-terminal sequencing of the intact protein and by partial peptide analysis employing fast atom bombardment-mass spectroscopy. The enzyme has a molecular weight of 94,038 based on its content of 838 amino acids.

Amino Acid Sequence↗
PubMed1987

19F magnetic resonance imaging of the reticuloendothelial system.

In this study sequential 1H and 19F magnetic resonance imaging methods were used to map the distribution of fluorinated compounds in vivo. An intravenously administered emulsion of perfluorooctylbromide (PFOB), an agent known to localize in the reticuloendothelial system, was detected in the liver and spleen of all studied hamsters and mice using 19F MRI. Lungs and salivary glands were also affected in some animals. Using a G. E. NMR CSI 2-T spectroscopy/imaging system, projection 19F images were obtained in 4 to 8 min. Subsequent mouse studies using a thick-slice driven equilibrium pulse sequence produced 19F images with an improved signal-to-noise ratio in a shorter acquisition time. With PFOB, 19F MRI has the capability of detecting macrophages in the reticulo-endothelial system and in other sites where macrophages congregate. This is the first report where the reticuloendothelial system was specifically imaged in live animals and where driven equilibrium imaging techniques have been applied to 19F MRI.

Animals↗
PubMed1986

Malignant peripheral nerve sheath tumor arising in an adrenal ganglioneuroma in an adult male homosexual.

The authors report a case of malignant peripheral nerve sheath tumor arising in an adrenal ganglioneuroma in an adult. This is the first such case occurring in the absence of a history of childhood neuroblastoma treated with radiation, and provides evidence that such a transformation can occur spontaneously. The neoplasm demonstrated a highly malignant biologic behavior with rapid growth, local recurrence, and metastasis.

Adrenal Gland Neoplasms↗
PubMedDate not supplied

Immediate reconstruction of the perineal wound with gracilis muscle flaps following abdominoperineal resection and intraoperative radiation therapy for recurrent carcinoma of the rectum.

BACKGROUND: Morbidity associated with a nonhealing perineal wound is the most common complication following proctectomy, particularly in the setting of recurrent carcinoma of the rectum and radiation therapy. Immediate reconstruction using the gracilis myocutaneous and muscle flaps significantly reduces the incidence of major infection associated with perineal wound closure. The purpose of this study was to assess the value of immediate reconstruction of the perineal wound using a gracilis flap in patients undergoing abdominoperineal resection and intraoperative radiation therapy. METHODS: This study retrospectively reviewed our experience with immediate pelvic reconstruction using gracilis muscle flaps for patients undergoing rectal extirpation and irradiation for recurrent carcinoma of the rectum. From 1990 to 1995, 16 patients underwent abdominoperineal resection (APR) or pelvic exenteration accompanied by immediate wound closure with unilateral or bilateral gracilis muscle flaps. Morbidity and mortality outcomes were compared to those of 24 patients from our institution who, between 1988 and 1992, underwent proctectomy and irradiation for recurrent rectal carcinoma with primary closure of the perineal wound. RESULTS: Major complications (i.e., major infection requiring hospitalization and/or operation) occurred in 2 (12%) of the patients with gracilis flaps versus 11 (46%) of the patients with primary closure (P = .028 by chi2 analysis for flap vs. primary closure). Minor complications (i.e., persistent sinus and subcutaneous abscess) occurred in 4 (25%) of the patients with gracilis flaps versus 5 (21%) of those with primary closure. CONCLUSION: Immediate perineal reconstruction using the gracilis myocutaneous flap following proctectomy and irradiation for recurrent rectal carcinoma significantly reduces the incidence of major infection associated with perineal wound closure.

Abdomen↗
PubMedDate not supplied

Acute cerebral ischemia in rabbits: correlation between MR and histopathology.

The histologic description of cerebral ischemia is complex, and within most lesions there are regional variations in degrees of neuronal cell injury, edema, and neuropil disruption. These parameters of tissue injury were analyzed histopathologically in transient and permanent experimental cerebral ischemia in 15 rabbits and the results were spatially correlated with MR images of pre- and postmortem (formalin-fixed) brains. MR was performed at 1.5 T (eight animals) and at 0.38 T (seven animals). Areas of high signal on T2-weighted MR images were closely correlated with histologic signs of cytotoxic glial edema and with disruption of the neuropil (widening of the interstitial spaces in the background matrix of glial and neuronal cellular processes), but MR tended to underestimate the extent of ischemic neuronal injury, especially low-grade histologic changes (mild neuronal shrinkage and nuclear basophilia). Low-grade ischemic neuronal changes were often found in the penumbra zone of ischemic lesions in areas that appeared normal on T2-weighted MR. High-grade neuronal injury was also seen occasionally in areas of normal signal on MR, especially in the striatum. No significant differences were seen on T2-weighted MR between the experimental groups with respect to transient vs permanent occlusion, in vivo vs in vitro MR, and low vs high magnetic field. In the setting of suspected acute cerebral ischemia, an abnormal T2-weighted MR study often underestimates the extent of neuronal ischemic injury, especially potentially reversible injury; and a normal MR study does not completely exclude significant neuronal ischemic injury.

Acute Disease↗
PubMedDate not supplied

Epstein-Barr virus-associated gastric adenocarcinoma among Japanese Americans in Hawaii.

This study confirms the observation that some gastric adenocarcinomas contain Epstein-Barr viral (EBV) sequences in their carcinoma cells. EBV sequences were detected by polymerase chain reaction and in situ hybridization in the tumors of 19 of 187 (10.2%) Japanese-American men and women living in Hawaii. The EBV-associated gastric cancers were more frequently present in men than in women: 14 of 99 (14.3%) men versus 5 of 88 (5.7%) women (P = 0.046). EBV type A was found in 17 of the 19 EBV-associated cancers, a finding consistent with the type A predominance in Japanese populations. Intestinal and diffuse-type tumors were both EBV-positive, and moderate to marked inflammation was usually present. The virus was not found in adjacent normal nonneoplastic mucosal cells or in mucosa showing intestinal metaplasia. EBV-associated tumors were found at stages 1 or 2 in 53% of cases, compared with 36% of the EBV-negative cancers (P = 0.13). The presence of EBV did not appear to influence survival. The relatively high incidence of gastric cancer compared to other EBV-associated tumors makes EBV-associated gastric cancer potentially one of the most common EBV-related tumors in the United States.

Adenocarcinoma↗
PubMedDate not supplied

CT angiography in the evaluation of acute stroke.

PURPOSE: To determine the worth of CT angiography of the circle of Willis as a supplement to routine CT in the examination of patients with symptoms of acute stroke in terms of its depiction of the number and distribution of arterial stenoses or occlusions. We also sought to compare the accuracy of CT angiography with MR angiography and/or digital subtraction angiography (DSA). METHODS: One hundred forty-five patients with symptoms of acute stroke were examined with routine head CT and CT angiography of the circle of Willis. MR angiography was also performed in 27 patients and DSA in 28 patients. CT and MR angiograms and DSAs were reviewed for stenoses or occlusions involving the vessels about the circle of Willis. MR and CT angiograms were also evaluated for image quality, and the corresponding routine CT and MR studies were evaluated for the presence of arterial infarction. RESULTS: CT angiograms were rated good or excellent in 89% of cases whereas MR angiograms were rated good or excellent in 92% of cases. Arterial stenoses or occlusions were present on 43% of CT angiograms, 48% of MR angiograms, and 21% of DSAs. Findings were in agreement in 98% of the vessels analyzed by CT angiography and MR angiography. Similarly, there was overall agreement of findings in 99% of vessels analyzed by CT angiography and DSA. None of the patients had any immediate adverse reactions after administration of intravenous nonionic iodinated contrast material. CONCLUSION: CT angiography is an accurate and safe method for evaluating arterial stenoses or occlusions in the vessels about the circle of Willis. CT angiography should be used in patients with symptoms of acute stroke for whom evaluation of the intracranial vasculature is desirable.

Adult↗