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Preoperative detection of hepatocellular carcinoma: ferumoxides-enhanced mr imaging versus combined helical CT during arterial portography and CT hepatic arteriography. AJR Am J Roentgenol 2001; 176:475-82. [PMID: 11159099 DOI: 10.2214/ajr.176.2.1760475] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
OBJECTIVE The purpose of this study was to compare ferumoxides-enhanced MR imaging with combined helical CT during arterial portography and CT hepatic arteriography for preoperative detection of hepatocellular carcinomas. SUBJECTS AND METHODS Twenty patients with 30 hepatocellular carcinomas underwent ferumoxides-enhanced MR imaging and combined helical CT during arterial portography and CT hepatic arteriography. The diagnosis was established by pathologic examination after surgical resection in 18 patients and by biopsy in two. The MR protocol included fast spin-echo with two echo times, T2(*)-weighted fast multiplanar gradient-recalled acquisition in the steady state, proton density-weighted fast multiplanar spoiled gradient-recalled echo, and T1-weighted fast multiplanar spoiled gradient-recalled echo images. The MR images of all sequences and the paired CT during arterial portography and CT hepatic arteriography images were independently evaluated by three radiologists on a segment-by-segment basis. Diagnostic accuracy was assessed with receiver operating characteristic analysis. RESULTS The accuracies (A(z) values) of ferumoxides-enhanced MR imaging and combined CT during arterial portography and CT hepatic arteriography for all observers were 0.964 and 0.948, respectively. The mean sensitivities of MR imaging and CT were 93% and 91%, respectively. The differences were not statistically significant. The mean specificity of MR imaging (99%) was significantly higher than that of combined CT during arterial portography and CT hepatic arteriography (94%). CONCLUSION Ferumoxides-enhanced MR imaging can be used successfully in place of combined CT during arterial portography and CT hepatic arteriography for the preoperative evaluation of patients with hepatocellular carcinomas.
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Abstract
PURPOSE The purpose of this work was to describe the helical CT findings of intestinal metastasis from gastric adenocarcinoma. METHOD Twenty-three patients with intestinal metastasis from gastric adenocarcinoma found at helical CT were included. CT findings and clinical and pathologic data were reviewed. RESULTS The most common characteristic finding was target-like concentric bowel wall thickening (thick inner high-outer low, n = 18) involving multiple long segments with progressive thickening of the enhancing inner layer. Fifteen cases (65%) involved multiple sites, and the ascending colon (n = 12) and rectum (n = 11) were the two most common sites. Peritoneal carcinomatosis (n = 15, 65%) and bowel obstruction (n = 14, 61%) were common associated findings. Regarding the primary lesion, the majority was linitis plastica (n = 16) and poorly differentiated adenocarcinoma with or without signet-ring cell differentiation (n = 14). CONCLUSION Intestinal metastasis from gastric adenocarcinoma, especially of the linitis plastica type, most commonly showed target-like long segmental wall thickening with a characteristically thick inner enhancing layer on helical CT.
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17Beta-estradiol inhibits proliferation of cultured vascular smooth muscle cells induced by lysophosphatidylcholine via a nongenomic antioxidant mechanism. Menopause 2001; 8:58-64. [PMID: 11201517 DOI: 10.1097/00042192-200101000-00010] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
OBJECTIVE Lysophosphatidylcholine (lysoPC), an active component of oxidized low-density lipoprotein, stimulates proliferation of vascular smooth muscle cells (VSMC). We investigated the direct impact of 17beta-estradiol (E2) on the proliferation of VSMC from rat aorta. RESULTS VSMC derived from both female and male rats expressed estrogen receptors alpha and beta. Treatments with 1% fetal bovine serum or 5 microM lysoPC increased the incorporation of [3H]-thymidine in VSMC obtained from female rats. 17Beta-E2 did not alter the response to fetal bovine serum, but significantly suppressed the enhanced deoxyribonucleic acid synthesis which had been induced by lysoPC in a dose-dependent manner (10(-4)-10(-6) M). Estrogen also inhibited the proliferation of VSMC from male animals. ICI 182,780, a specific estrogen receptor antagonist, and 17alpha-E2, an inactive form of estradiol, also decreased the mitogenic response to lysoPC in VSMC. In addition, N-acetyl-L-cysteine, a potent antioxidant, inhibited the lysoPC effect. Flow cytometric analysis using the oxidation-sensitive probe 2',7'-dichlorofluorescin diacetate revealed that elevated intracellular formation of reactive oxygen species elicited with lysoPC was depressed significantly by 17beta-E2, ICI 182,780, or 17alpha-E2 as well as by N-acetyl-L-cysteine. CONCLUSION 17Beta-E2 inhibits in vitro VSMC proliferation induced by lysoPC via a nongenomic antioxidant mechanism.
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MESH Headings
- Animals
- Antioxidants/pharmacology
- Aorta, Thoracic
- Cell Division/drug effects
- Cells, Cultured
- Estradiol/pharmacology
- Estrogen Receptor alpha
- Estrogen Receptor beta
- Female
- Fetal Blood
- Flow Cytometry
- Lysophosphatidylcholines/pharmacology
- Male
- Muscle, Smooth, Vascular/chemistry
- Muscle, Smooth, Vascular/cytology
- Muscle, Smooth, Vascular/drug effects
- RNA, Messenger/analysis
- Rats
- Rats, Sprague-Dawley
- Reactive Oxygen Species/metabolism
- Receptors, Estrogen/genetics
- Reverse Transcriptase Polymerase Chain Reaction
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Abstract
PURPOSE The aim was to evaluate whether the expression of cyclin D2 mRNA in human luteinized granulosa cells correlates with the clinical parameters of women undergoing in vitro fertilization-embryo transfer (IVF-ET) programs. METHODS Using reverse transcriptase-polymerase chain reaction (RT-PCR) techniques, the cyclin D2 mRNA in human luteinized granulosa cells of large follicles was measured. Correlation analysis between cyclin D2 mRNA expression and clinical parameters [age; day 3 follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2); E2 and P4 at the day of human chorionic gonadotropin (hCG); total amount of gonadotropin and the number of days of gonadotropin administration; pregnancy outcome] were performed. RESULT(S) Cyclin D2 mRNA expression showed negative correlation with patient's age (R = -0.60, P < 0.005) and total amount of gonadotropins (R = -0.45, P < 0.03), and also showed positive correlation with serum E2 levels at the day of hCG administration (R = 0.55, P < 0.02). Other clinical parameters showed no statistical significance. Cyclin D2 mRNA expression of pregnant group was higher than that of nonpregnant group (P < 0.03). CONCLUSIONS Cyclin D2 mRNA expression in human luteinized granulosa cells positively correlates with clinical parameters of ovarian function and may be a novel marker for the health of human ovarian follicle.
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Hepatocellular carcinoma treated with percutaneous radio-frequency ablation: usefulness of power Doppler US with a microbubble contrast agent in evaluating therapeutic response-preliminary results. Radiology 2000; 217:558-63. [PMID: 11058660 DOI: 10.1148/radiology.217.2.r00oc07558] [Citation(s) in RCA: 114] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE To evaluate the usefulness of power Doppler ultrasonography (US) with a microbubble contrast agent in assessing the therapeutic response of hepatocellular carcinomas (HCCs) treated with percutaneous radio-frequency (RF) ablation. MATERIALS AND METHODS Forty patients with 45 nodular HCC lesions 1.0-3.8 cm in diameter underwent power Doppler US before and after intravenous injection of a microbubble contrast agent. The same procedures were repeated after US-guided percutaneous RF ablation. The results of these studies were compared with those of three-phase helical computed tomography (CT) performed immediately after RF ablation. RESULTS Before RF ablation, nonenhanced power Doppler US demonstrated flow signals within tumor in 33 of 45 HCCs. After contrast agent administration, flow signals increased or newly appeared in all cases. After RF ablation, none of the ablated tumors showed intratumoral flow signals at nonenhanced power Doppler US, whereas six showed marginal intratumoral flow signals at contrast agent-enhanced power Doppler US. These six tumors were found to have small enhancing foci, suggestive of viable tumor, in corresponding areas at immediate follow-up CT. Additional RF ablation or transcatheter arterial chemoembolization was performed in these tumors. CONCLUSION The results of power Doppler US with a microbubble contrast agent in HCCs treated with RF ablation correlated well with those of contrast-enhanced CT. Preliminary data suggest that contrast-enhanced power Doppler US can be a promising noninvasive technique for assessing therapeutic response.
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Cervical x-rays and the atlanto-axial region: supplementary computed tomography may be required in trauma. Scott Med J 2000; 45:151. [PMID: 11130300 DOI: 10.1177/003693300004500508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In cervical trauma, x-rays may require supplementation with dynamic x-rays, computed-tomography (CT), or magnetic resonance imaging (MRI). A normal cervical x-ray does not always imply cervical stability. The mechanism of injury, symptoms and signs help to indicate whether further imaging is required. We report a patient with a fracture of the atlas that was not diagnosed by plain radiology, but seen on CT.
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Message from the editors. Neurobiol Dis 2000; 7:493. [PMID: 11042059 DOI: 10.1006/nbdi.2000.0356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Abstract
Advanced atherosclerosis is often associated with dystrophic calcification and remodeling of extracellular matrix of vascular wall. Recently many studies have documented a general relationship between calcification and severity of coronary disease, and discussed the feasibility of electron beam computed tomography for detecting and quantifying the coronary artery calcification in the patients. The present study investigated the expression and the localization of osteopontin, one of noncollagenous bone matrix protein, within the calcified coronary arteries. Autopsy-derived coronary artery specimens were scanned and reconstructed to visualize the pattern of coronary calcification using a novel microscopic computed tomography technique. The localization of the osteopontin were evaluated by immunohistochemial stain with LF7. The present study showed that the pattern of coronary calcification is variable and the expression of osteopontin is localized mainly to calcified lesion. The smooth muscle cells in addition to macrophage expressed osteopontin protein in human coronary atherosclerotic plaques. Soluble osteopontin released near to the sites of vascular calcification may represent an adaptive mechanism aimed at regulating the process of vascular calcification.
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261
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Abstract
Assisted hatching (AH), which is known to improve the hatching potential of mammalian embryos, has been used to increase the pregnancy rate in in vitro fertilization cycles. However, the effect of AH on a trypsin-like protease, which is known to be associated with the hatching process, has not been studied. In this study, we evaluate whether the intactness of zona pellucida affects the secretion of a trypsin-like protease from mouse blastocyst. Four- to 8-cell stage mouse embryos were collected at 66- to 68 hr after hCG injection and divided into 3 groups according to the manipulation of zona pellucida. The groups are no treatment (control), drilling of zona pellucida (ZD) and thinning of zona pellucida (ZT). The activity of a trypsin-like protease, blastocyst development and hatching rate were compared among the three groups at 110 and 135 hr after hCG injection, respectively. The protease activity and blastocyst development were not significantly different among control, ZD and ZT groups at 110 and 135 hr after hCG injection, respectively. However, the hatching rate of ZD and ZT groups was significantly higher than that of control group at each time, respectively (p<0.001). Even in the zona pellucida removed embryos, the protease activity did not differ from the control group. In conclusion, the secretion of a trypsin-like protease from mouse blastocyst does not seem to be affected by the intactness of zona pellucida.
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Comparative performances of an HTLV-I/II EIA and other serologic and PCR assays on samples from persons at risk for HTLV-II infection. Transfusion 2000; 40:924-30. [PMID: 10960518 DOI: 10.1046/j.1537-2995.2000.40080924.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND HTLV-I and HTLV-II are related exogenous pathogenic human retroviruses. Until recently, ELISAs based on HTLV-I antigens have been used to screen for the presence of HTLV-I or -II antibodies. The HTLV-I-based assays have not been as sensitive in detecting antibodies to HTLV-II as in detecting antibodies to HTLV-I. The Abbott HTLV-I/HTLV-II ELISA uses a combination of HTLV-I and HTLV-II antigens to detect antibodies to the whole HTLV group. The performance of this ELISA was compared to that of several HTLV-I-based serologic assays and an HTLV-II PCR assay in cohorts of South American Indians and New York City IV drug users (IVDUs) in whom HTLV-II is endemic. STUDY DESIGN AND METHODS Sera from 429 South American Indians and New York City IVDUs were evaluated for HTLV antibodies by the use of three ELISAs (rgp21-enhanced HTLV-I/II, Cambridge Biotech; Vironostika HTLV-I/II, Organon Teknika; and HTLV-I/HTLV-II, Abbott), and a Western blot (WB) assay. Peripheral blood leukocyte DNA from each person was analyzed for HTLV-I and HTLV-II pol DNA via PCR. The HTLV-II PCR-positive samples were further subtyped via cloning and sequencing and/or oligomer restriction. RESULTS Two hundred four samples (48%) were positive for HTLV-II by serologic and/or PCR assays. All of the positive samples from the Indians and approximately one-third of the positive samples from the IVDUs were of the HTLV-IIB subtype. Comparative analyses indicate that the sensitivity and specificity of the various assays were: PCR, 98 and 100 percent; Abbott HTLV-I/HTLV-II, 78 and 95 percent; Cambridge Biotech HTLV-I/II, 76 and 96 percent; Vironostika HTLV-I/II, 71 and 98 percent; and WB, 73 and 100 percent, respectively. CONCLUSION There were no significant differences among the sensitivities and specificities of the HTLV-I/II ELISAs (p values, 0.056-0.438). The WB and PCR assays were much more specific than the other serologic assays (p</=0.03). However, the PCR assay is significantly (p<0.001) more sensitive than any of the serologic assays in the detection of HTLV-II infection. Thus, optimal detection of HTLV-II infection would seem to require both serologic and DNA PCR assays.
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The incidence of neurosurgical disease in patients who are referred to a neurosurgical centre for CT scanning: should district general hospital scanners be more active? Scott Med J 2000; 45:113-4. [PMID: 11060913 DOI: 10.1177/003693300004500405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This study assessed the incidence of neurosurgical intervention in those patients who were referred to a neurosurgical unit for a CT scan in whom the diagnosis was unclear. A prospective consecutive patient survey was performed over a 29 week period in a regional neurosurgical unit. One hundred patients were included. Twenty-eight patients required neurosurgical management, of whom, nine required surgery within 24 hours. Twenty-three patients required ventilation, of whom 14 did not have a neurosurgical condition. In this group of patients, the majority did not have a neurosurgical condition. Increasing the availability of scanning services in district hospitals may avoid the unnecessary transfer of potentially unstable patients.
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265
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A novel proteinase inhibitor gene transiently induced by tobacco mosaic virus infection. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1492:509-12. [PMID: 11004521 DOI: 10.1016/s0167-4781(00)00126-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A gene (NgPI) encoding a novel proteinase inhibitor (PI) has been isolated from tobacco leaves. Protein encoded by the gene consists of 241 amino acid residues having a predicted molecular mass of 26.7 kDa and a calculated pI of 8.7. A predicted N-terminal signal sequence followed by a vacuolar targeting signal and a peptide conserved in the Kunitz type PIs were identified. The deduced NgPI protein has sequence homology with aspartic and cysteine protease inhibitors. The gene is present as double copies in the Nicotiana glutinosa genome. Expression of the NgPI gene is rapidly and transiently induced by tobacco mosaic virus infection at a time earlier than apparent lesions of hypersensitive responses appear on the leaves.
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CHRK1, a chitinase-related receptor-like kinase in tobacco. PLANT PHYSIOLOGY 2000; 123:905-15. [PMID: 10889239 PMCID: PMC59053 DOI: 10.1104/pp.123.3.905] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/1999] [Accepted: 03/17/2000] [Indexed: 05/18/2023]
Abstract
A cDNA encoding a chitinase-related receptor-like kinase, designated CHRK1, was isolated from tobacco (Nicotiana tabacum). The C-terminal kinase domain (KD) of CHRK1 contained all of the conserved amino acids of serine/threonine protein kinases. The putative extracellular domain was closely related to the class V chitinase of tobacco and to microbial chitinases. CHRK1 mRNA accumulation was strongly stimulated by infection with fungal pathogen and tobacco mosaic virus. Amino acid-sequence analysis revealed that the chitinase-like domain of CHRK1 lacked the essential glutamic acid residue required for chitinase activity. The recombinant chitinase-like domain did not show any catalytic activity for either oligomeric or polymeric chitin substrates. The recombinant KD of CHRK1 exhibited autophosphorylation, but the mutant KD with a mutation in the essential ATP-binding site did not, suggesting that CHRK1 encoded a functional kinase. CHRK1 was detected in membrane fractions of tobacco BY2 cells. Furthermore, CHRK1-GFP fusion protein was localized in plasma membranes when it was expressed in animal cells. This is the first report of a new type of receptor-like kinase containing a chitinase-like sequence in the putative extracellular domain.
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Effects of electric stimulation on bovine oocyte activation and embryo development in intracytoplasmic sperm injection procedure. J Assist Reprod Genet 2000; 17:310-4. [PMID: 11042826 PMCID: PMC3455396 DOI: 10.1023/a:1009496726343] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE This study was carried out to investigate the efficacy of electric stimulation before and/or after intracytoplasmic sperm injection (ICSI) on bovine oocyte activation and embryo development. METHODS The oocytes were treated with electric shock before (B), before and after (B&A), and after (A) sperm injection. In each group, sham ICSI (ICSI-s) was performed to exclude the effect of parthenogenesis (B ICSI-s, B&A ICSI-s, and A ICSI-s). An electric pulse was applied with a single direct current (DC) pulse (0.8 kV/cm, 70 microseconds). RESULTS One pronucleus (PN) formation in the B&A ICSI-s group was slightly higher than that found in B and B&A ICSI group; however, the difference was not significant. Two PN formation in B&A ICSI group was higher than that found in sham ICSI groups (P < 0.05). There were no differences among treatment groups in the cleavage rate; however, morulae and blastocyst formation in the B&A embryos was significantly higher than that of other groups (P < 0.05) and got pregnant. CONCLUSIONS Electric stimulation before and after injection was an effective method in inducing bovine oocyte activation and in sustaining embryo development to the morulae and blastocyst stage.
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Abstract
The authors have developed and evaluated a radiation oncology digital image chart system (RODICS). With this system we could achieve paperless and filmless practice, and thus improved operational efficiency within the department. In this paper, we describe characteristics and clinical usage of RODICS.
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An integrated service digital network (ISDN)-based international telecommunication between Samsung Medical Center and Hokkaido University using telecommunication helped radiotherapy planning and information system (THERAPIS). Radiother Oncol 2000; 56:121-3. [PMID: 10869763 DOI: 10.1016/s0167-8140(00)00179-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This study introduces the integrated service digital network (ISDN)-based international teleradiotherapy system (THERAPIS) in radiation oncology between hospitals in Seoul, South Korea and in Sapporo, Japan. THERAPIS has the following functions: (1) exchange of patient's image data, (2) real-time teleconference, and (3) communication of the treatment planning, dose calculation and distribution, and of portal verification images between the remote hospitals. Our preliminary results of applications on eight patients demonstrated that the international telecommunication using THERAPIS was clinically useful and satisfactory with sufficient bandwidth for the transfer of patient data for clinical use in radiation oncology.
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Structure and stress-related expression of two cDNAs encoding proteinase inhibitor II of Nicotiana glutinosa L. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1492:211-5. [PMID: 11004491 DOI: 10.1016/s0167-4781(00)00073-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Two cDNAs, pNGPI-1 and pNGPI-2, encoding Nicotiana glutinosa proteinase inhibitor II (PI-II) have been cloned, sequenced and identified. The deduced amino acid sequences are 54-82% identical to those of other plant PI-II. The NGPI-1 protein is composed of eight repeated domains, while NGPI-2 contains six repeated regions, each with a putative reactive site. The expression of NGPI-1 is highly regulated in a developmental- and tissue-specific manner, with the transcript being detected in young leaves and floral organs of N. glutinosa plants. In mature leaves, the NGPI-1 gene is rapidly activated by distinct temporal induction patterns in response to pathogen-related (biotic) and wound-related (abiotic) stresses.
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Abstract
With the graying of America comes an increasing demand for medical care of the elderly. Unfortunately, due to a combination of rising costs of health care and driving force from the public to lower spending, health maintenance organizations and insurance companies are less willing to pay for expensive surgical procedures. Recently, infrainguinal arterial reconstructions have been denied at our institution solely on the basis of patient's age, without adequate assessment of data. We evaluated the results of patients aged over 80 years who underwent infrainguinal reconstruction and compared them to results of younger cohorts during the same time period. From 1989 to 1998, 629 octogenarians had infrainguinal reconstructions performed at our institution. In the same time period, 3257 procedures were performed on patients <80 years old. Demographics, indications for operations, and outcomes were compared. Statistical analysis was performed with Fisher's exact test and log rank analysis, assuming significance for p < 0.05. Indications for operation were significantly more often limb salvage and less often claudication in the older group. Nonfatal complication rates were similar. Primary and secondary patency rates as well as limb salvage rates were comparable in both groups. Patients who are >80 years of age should expect comparable outcomes to those of their younger cohorts when undergoing infrainguinal reconstructions. Health care dollars can be well spent on octogenarians and age should not be a contraindication for infrainguinal reconstruction.
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Trends in the vertical distribution of ozone: A comparison of two analyses of ozonesonde data. ACTA ACUST UNITED AC 1999. [DOI: 10.1029/1999jd900300] [Citation(s) in RCA: 158] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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White-matter change in mesial temporal sclerosis: correlation of MRI with PET, pathology, and clinical features. Epilepsia 1999; 40:1634-41. [PMID: 10565593 DOI: 10.1111/j.1528-1157.1999.tb02050.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To assess the magnetic resonance imaging (MRI), positron emission tomography (PET), pathology, and clinical findings of patients with the MRI feature of white-matter change (WMC) in the anterior temporal lobe. METHODS Fifty-six patients with pathologically proven mesial temporal sclerosis were included in this study. MRI and 18F-2-deoxyglucose-(FDG) PET images were obtained before surgery in all patients. The patients were divided into two groups according to the presence of WMC on their MRI. WMC consists of an indistinct gray-white matter demarcation and an increased signal intensity of the anterior temporal lobe on T2-weighted images. The two groups were then compared in terms of MRI, PET, pathology, and clinical features. RESULTS The MRI feature of WMC was observed in 18 (32%) of the 56 patients. PET images of those patients revealed more severe hypometabolism of the ipsilateral temporal lobes (p< 0.05). In terms of histologic findings, larger numbers of heterotopic neurons were observed in the anterior temporal lobe white matter of these patients who also shared the following clinical features: earlier seizure onset, frequent history of febrile convulsions, and favorable surgical outcomes. CONCLUSIONS The MRI feature of WMC is an additive sign for correct seizure lateralization and may be related to a favorable surgical outcome in patients with temporal lobe epilepsy.
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Abstract
BACKGROUND Limited replicative capacity is a defining characteristic of most normal human cells and culminates in senescence, an arrested state in which cells remain viable but display an altered pattern of gene and protein expression. To survey widely the alterations in gene expression, we have developed a DNA microarray analysis system that contains genes previously reported to be involved in aging, as well as those involved in many of the major biochemical signaling pathways. RESULTS Senescence-associated gene expression was assessed in three cell types: dermal fibroblasts, retinal pigment epithelial cells, and vascular endothelial cells. Fibroblasts demonstrated a strong inflammatory-type response, but shared limited overlap in senescent gene expression patterns with the other two cell types. The characteristics of the senescence response were highly cell-type specific. A comparison of early- and late-passage cells stimulated with serum showed specific deficits in the early and mid G1 response of senescent cells. Several genes that are constitutively overexpressed in senescent fibroblasts are regulated during the cell cycle in early-passage cells, suggesting that senescent cells are locked in an activated state that mimics the early remodeling phase of wound repair. CONCLUSIONS Replicative senescence triggers mRNA expression patterns that vary widely and cell lineage strongly influences these patterns. In fibroblasts, the senescent state mimics inflammatory wound repair processes and, as such, senescent cells may contribute to chronic wound pathologies.
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Molecular cloning of a catalase cDNA from Nicotiana glutinosa L. and its repression by tobacco mosaic virus infection. Mol Cells 1999; 9:320-5. [PMID: 10420993] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
Recent reports revealed that catalase has a role in the plant defense mechanism against a broad range of pathogens through being inhibited by salicylic acid (SA). During an effort to clone disease resistance-responsive genes, a cDNA encoding catalase (Ngcat1; Nicotiana glutinosa cat1) was isolated from a tobacco cDNA library. In N. glutinosa, catalase is encoded by a small gene family. The deduced amino acid sequence of the Ngcat1 cDNA has 98% homology with the cat1 gene of N. plumbaginifolia. The Ngcat1 expression is controlled by the circadian clock, and its mRNA level is the most abundant in leaves. Both the expression of Ngcat1 mRNA and its enzyme activity in the tobacco plant undergoing a hypersensitive response (HR) to TMV infection were repressed. The repression of the mRNA level was also observed following treatment with SA. These results imply that SA may act as an inhibitor of catalase transcription during the HR of tobacco. Cloning and expression of the Ngcat1 in tobacco following pathogen infection and SA treatment are presented.
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Long-lasting sonographic and histopathological findings in cured clonorchiasis of rabbits. THE KOREAN JOURNAL OF PARASITOLOGY 1999; 37:77-83. [PMID: 10388265 PMCID: PMC2733060 DOI: 10.3347/kjp.1999.37.2.77] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
To ascertain residual sonographic and histopathological findings of clonorchiasis after treatment, the present study evaluated sonographic findings in rabbits which were infected with 500 metacercariae of C. sinensis every 6 months for 18 months after treatment with praziquantel. The sonographic findings were analyzed in terms of intrahepatic bile duct dilatation and periductal echogenicity, and histopathological findings were observed after the last sonographic examination. Compared with the sonographic findings before treatment, dilatation of the intrahepatic bile ducts became mild to some degree in four of the seven cases and increased periductal echogenicity resolved in four of them. The histopathological specimens after 18 months showed that periductal inflammation has almost resolved but moderate dilatation of the intrahepatic ducts and mucosal hyperplasia persisted. The periductal fibrosis minimally resolved. The long-lasting sonographic findings in cured clonorchiasis make sonography less specific.
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An experimental study of the influence of steroid irrigation on bone formation around implants inserted into the irradiated tibia of rabbits. Int J Oral Maxillofac Surg 1999. [DOI: 10.1016/s0901-5027(99)80741-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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280
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To eat or not to eat, that is the question... Ann Neurol 1999; 45:4-5. [PMID: 9894869 DOI: 10.1002/1531-8249(199901)45:1<4::aid-art2>3.0.co;2-c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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281
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Abstract
PURPOSE The purpose of this work was to describe the radiologic findings of pulmonary tuberculosis in patients who presented with acute respiratory failure. METHODS We included patients who had newly diagnosed active pulmonary tuberculosis and who presented with acute respiratory failure. Initial chest radiographic (n = 17) and high-resolution CT (n = 11) findings of each patient were analyzed retrospectively. RESULTS Of 1,010 patients with active pulmonary tuberculosis, 17 patients (1.7%) presented with acute respiratory failure. Nine (53%) of the 17 patients died. The most common initial chest radiographic findings were small nodular lesions (16/17; 94%), consolidation (13/17; 76%), and ground-glass opacity (12/17; 70%). Eleven (69%) of 16 nodular lesions, 9 of 13 (69%) consolidations, and 10 of 12 (83%) ground-glass opacities were bilateral. On HRCT (n = 11), miliary micronodular lesions were seen in 6 patients (55%), whereas bronchogenic spread of tuberculosis with disseminated centrilobular nodules and tree-in-bud appearance was seen in 5 patients (45%). Diffuse areas of ground-glass attenuation were seen in all six patients with miliary nodules and four of five patients with bronchogenic spread of tuberculosis. CONCLUSION Patients with pulmonary tuberculosis occasionally present with acute respiratory failure. In this condition, chest radiograph most commonly shows bilateral small nodular lesions mixed with consolidation or ground-glass opacity, whereas HRCT demonstrates findings of miliary or bronchogenic disseminated tuberculosis with diffuse areas of ground-glass attenuation.
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282
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Cadmium resistance in transgenic tobacco plants expressing the Nicotiana glutinosa L. metallothionein-like gene. Mol Cells 1998; 8:678-84. [PMID: 9895119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
To understand the function of metallothioneins (MTs) in plants, we introduced the Nicotiana glutinosa MT gene into tobacco (N. tabacum) plants via an Agrobacterium mediated transformation. Full-length MT cDNA was fused between the cauliflower mosaic virus 35S (CaMV 35S) promoter and the nopaline synthase (nos) terminator of the pMBP1 binary vector in sense orientation. Tobacco leaf discs which were cocultivated with Agrobacterium carrying the chimeric MT gene, formed kanamycin-resistant shoots on medium containing kanamycin. The kanamycin-resistant shoots were subsequently rooted on medium containing 200 microM CdSO4. Approximately 30% of individual transgenic plants developed normally. Nontransgenic plants promptly underwent leaf chlorosis, and their growth and development were inhibited on MS medium containing 50 microM CdSO4. Genomic Southern blot analysis showed that the MT gene was stably integrated into the nuclear genome of transgenic tobacco plants. The expression level of MT transcripts was analyzed by RNA gel blot analysis. Self-pollinated seeds obtained from transgenic tobacco plants showing cadmium tolerance were germinated on a medium containing 100 microM CdSO4. PCR analysis from sensitive and stably resistant T2 seedlings for cadmium sulfate confirmed a high correlation between the phenotypic expression of the MT gene and the transgenic genotype, indicating that the MT gene is inherited in the next generation.
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MESH Headings
- Cadmium/pharmacology
- Cloning, Molecular
- DNA, Plant/analysis
- DNA, Plant/genetics
- Drug Resistance
- Gene Expression Regulation, Plant
- Genes, Plant/genetics
- Genome, Plant
- Metallothionein/genetics
- Plants/genetics
- Plants, Genetically Modified/drug effects
- Plants, Genetically Modified/genetics
- Plants, Toxic
- Recombinant Fusion Proteins/genetics
- Seeds/genetics
- Nicotiana/genetics
- Transformation, Genetic
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283
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Noradrenergic neurotoxin suppresses gonadotropin-releasing hormone (GnRH) and GnRH receptor gene expression in ovariectomized and steroid-treated rats. J Neuroendocrinol 1998; 10:911-8. [PMID: 9870748 DOI: 10.1046/j.1365-2826.1998.00278.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The present study was designed to investigate whether noradrenergic neurotransmission regulates the gene expression of gonadotropin-releasing hormone (GnRH) in the preoptic area and GnRH receptor in the pituitary. To this end, N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4, 50 mg/kg), an intraperitoneal (i.p.) injection of selective noradrenergic neurotoxin, was administered 1 h before progesterone (1 mg) treatment in ovariectomized and estradiol-treated prepubertal rats. Treatment with DSP4 effectively blocked the progesterone-induced increase in hypothalamic noradrenaline content, but not dopamine content, indicating that DSP4 selectively inhibits noradrenergic neurotransmission. DSP4 significantly blocked progesterone-induced increase in serum luteinizing hormone (LH) concentrations as well as GnRH release from hypothalamic fragments incubated in vitro. DSP4 concomitantly down-regulated GnRH mRNA levels in the preoptic area, as determined by competitive reverse transcription-polymerase chain reaction. DSP4 also clearly down-regulated progesterone-induced GnRH receptor mRNA levels in the pituitary, whereas it failed to alter LHbeta mRNA levels. In summary, blockade of noradrenergic neurotransmission with DSP4 resulted in profound reductions of hypothalamic GnRH and pituitary GnRH receptor gene expression.
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284
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Dendritic cell-based vaccines in the setting of peripheral blood stem cell transplantation: CD34+ cell-depleted mobilized peripheral blood can serve as a source of potent dendritic cells. Clin Cancer Res 1998; 4:2709-16. [PMID: 9829733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We are investigating the use of tumor-pulsed dendritic cell (DC)-based vaccines in the treatment of patients with advanced cancer. In the current study, we evaluated the feasibility of obtaining both CD34+ hematopoietic stem/ progenitor cells (HSCs) and functional DCs from the same leukapheresis collection in adequate numbers for both peripheral blood stem cell transplantation (PBSCT) and immunization purposes, respectively. Leukapheresis collections of mobilized peripheral blood mononuclear cells (PBMCs) were obtained from normal donors receiving granulocyte colony-stimulating factor (G-CSF) (for allogeneic PBSCT) and from intermediate grade non-Hodgkin's lymphoma or multiple myeloma patients receiving cyclophosphamide plus G-CSF (for autologous PBSCT). High enrichment of CD34+ HSCs was obtained using an immunomagnetic bead cell separation device. After separation, the negative fraction of mobilized PBMCs from normal donors and cancer patients contained undetectable levels of CD34+ HSCs by flow cytometry. This fraction of cells was then subjected to plastic adherence, and the adherent cells were cultured for 7 days in GM-CSF (100 ng/ml) and interleukin 4 (50 ng/ml) followed by an additional 7 days in GM-CSF, interleukin 4, and tumor necrosis factor alpha (10 ng/ml) to generate DCs. Harvested DCs represented yields of 4.1+/-1.4 and 5.8+/-5.4% of the initial cells plated from the CD34+ cell-depleted mobilized PBMCs of normal donors and cancer patients, respectively, and displayed a high level expression of CD80, CD86, HLA-DR, and CD11c but not CD14. This phenotypic profile was similar to that of DCs derived from non-CD34+ cell-depleted mobilized PBMCs. DCs generated from CD34+ cell-depleted mobilized PBMCs elicited potent antitetanus as well as primary allogeneic T-cell proliferative responses in vitro, which were equivalent to DCs derived from non-CD34+ cell-depleted mobilized PBMCs. Collectively, these results demonstrate the feasibility of obtaining both DCs and CD34+ HSCs from the same leukapheresis collection from G-CSF-primed normal donors and cancer patients in sufficient numbers for the purpose of combined PBSCT and immunization strategies.
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285
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Coordinated expression of defense-related genes by TMV infection or salicylic acid treatment in tobacco. Mol Cells 1998; 8:388-92. [PMID: 9749524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
To understand the coordinated functions of the different classes of defense-related genes expressed in plant disease resistance, the expression patterns of pathogenesis related (PR) protein genes and genes involved in antioxidation and the production of secondary metabolites were examined. The expression patterns of the respective defense-related genes were monitored following TMV infection or salicylic acid treatment. Northern blot analyses showed that PR genes such as PR-1, beta-1,3-glucanase and chitinase were strongly induced in tobacco leaves upon TMV infection or salicylic acid treatment. 3-Hydroxy-3-methylglutaryl CoA reductase (HMGR) and phenylalanine ammonialyase (PAL), involved in isoprenoid and phenylpropanoid biosynthesis, respectively, were mildly induced at the late stage of normal hypersensitive response (HR) or after salicylic acid treatment when compared with the PR-gene expressions. However, in acute HR, they were strongly expressed at the early stage. Interestingly, the expression of the antioxidative genes, anionic peroxidase and ascorbate peroxidase, were inversely expressed following TMV infection and salicylic acid treatment. Differential expression of 3 groups of genes involved in plant defense responses are discussed in relation to different signal transduction pathways.
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286
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Intracranial course and relations of the hypoglossal nerve. An anatomic study. Surg Radiol Anat 1998; 20:109-12. [PMID: 9658529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
This anatomic study describes the course and intracranial relations of the hypoglossal n. in 32 cadavers. The rootlets of the nerve emerged as a fan-shaped distribution (23.44%) or in two bundles (76.56%) and converged towards the hypoglossal canal in the subarachnoid space before piercing the duramater. In 76.57% of cases the rootlets pierced the dura mater in two separate apertures, less commonly through the same aperture (21.87%), and in rare cases through three individual apertures, as in one of our cases. The distance between the two apertures varied from 0.6 mm to 8.7 mm. Commonly, the two bundles converged together and left the skull through one foramen in the skull. However, in some cases (28.12%), the hypoglossal canal was divided in two by a small bony spicule. In 23.45% of cases the initial course of the posterior inferior cerebellar a. (PICA) passed between the two bundles of the hypoglossal n. before ascending towards the lateral border of the fourth ventricle.
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287
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The role of tumor necrosis factor alpha in modulating the quantity of peripheral blood-derived, cytokine-driven human dendritic cells and its role in enhancing the quality of dendritic cell function in presenting soluble antigens to CD4+ T cells in vitro. Blood 1998; 91:4652-61. [PMID: 9616162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Because dendritic cells (DC) are critically involved in both initiating primary and boosting secondary host immune responses, attention has focused on the use of DC in vaccine strategies to enhance reactivity to tumor-associated antigens. We have reported previously the induction of major histocompatibility complex class II-specific T-cell responses after stimulation with tumor antigen-pulsed DC in vitro. The identification of in vitro conditions that would generate large numbers of DC with more potent antigen-presenting cell (APC) capacity would be an important step in the further development of clinical cancer vaccine approaches in humans. We have focused attention on identifying certain exogenous cytokines added to DC cultures that would lead to augmented human DC number and function. DC progenitors from peripheral blood mononuclear cells (PBMC) were enriched by adherence to plastic, and the adherent cells were then cultured in serum-free XVIVO-15 medium (SFM) for 7 days with added granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). At day 7, cultures contained cells that displayed the typical phenotypic and morphologic characteristics of DC. Importantly, we have found that the further addition of tumor necrosis factor alpha (TNFalpha) at day 7 resulted in a twofold higher yield of DC compared with non-TNFalpha-containing DC cultures at day 14. Moreover, 14-day cultured DC generated in the presence of TNFalpha (when added at day 7) demonstrated marked enhancement in their capacity to stimulate a primary allogeneic mixed leukocyte reaction (8-fold increase in stimulation index [SI]) as well as to present soluble tetanus toxoid and candida albicans (10- to 100-fold increases in SI) to purified CD4+ T cells. These defined conditions allowed for significantly fewer DC and lower concentrations of soluble antigen to be used for the pulsing of DC to efficiently trigger specific T-cell proliferative responses in vitro. When compared with non-TNFalpha-supplemented cultures, these DC also displayed an increased surface expression of CD83 as well as the costimulatory molecules, CD80 and CD86. Removal of TNFalpha from the DC cultures after 2 or 4 days reduced its enhancing effect on DC yield, phenotype, and function. Thus, the continuous presence of TNFalpha over a 7-day period was necessary to achieve the maximum enhancing effect observed. Collectively, our findings point out the importance of exogenous TNFalpha added to cultures of cytokine-driven human DC under serum-free conditions, which resulted in an enhanced number and function of these APC. On the basis of these results, we plan to initiate clinical vaccine trials in patients that use tumor-pulsed DC generated under these defined conditions.
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288
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Biotic and abiotic stress-related expression of 1-aminocyclopropane-1-carboxylate oxidase gene family in Nicotiana glutinosa L. PLANT & CELL PHYSIOLOGY 1998; 39:565-73. [PMID: 9697341 DOI: 10.1093/oxfordjournals.pcp.a029406] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Three full length 1-aminocyclopropane-1-carboxylate (ACC) oxidase cDNA clones (pNG-ACO1, 1,254 bp; pNG-ACO2, 1,198 bp; and pNG-ACO3, 1,053 bp) were isolated from the TMV-treated leaf cDNA library of Nicotiana glutinosa plant. They share a high degree of sequence identity (78-81%) throughout the coding regions but are divergent within the 3'-untranslated regions. The gene-specific probes were prepared using these regions to investigate the differential expression of the ACC oxidase gene family in various organs and in response to a multitude of biotic and abiotic stresses in N. glutinosa plants. All three genes were transcriptionally active displaying unique patterns of expression. Both the pNG-ACO1 and pNG-ACO3 transcripts highly accumulated during the senescence of leaves, while the pNG-ACO2 mRNA was constitutively present. In addition, the NG-ACO1 and NG-ACO3 transcripts were predominantly found in roots whereas the NG-ACO2 mRNA was mainly in stems. Upon TMV infection, both NG-ACO1 and NG-ACO3 were markedly induced, but in mock treatment which has an effect of mild wounding, only the NG-ACO3 gene was induced. Furthermore, salicylic acid and CuSO4 treatments of leaves increased the level of NG-ACO1 and NG-ACO3 transcripts, while they did not affect the NG-ACO2 gene expression. Results showed that both the NG-ACO1 and NG-ACO3 genes were highly inducible by ethylene and methyl jasmonate treatments, with NG-ACO3 being more responsive. By contrast, NG-ACO2 did not respond to these growth regulators. Thus, it appears that there are two groups of ACC oxidase transcripts expressed in leaf tissue of N. glutinosa, either stress-induced or constitutive. The possible molecular mechanism of differential regulation of ACC oxidase gene expression and its physiological significance are discussed.
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289
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Intracranial course and relations of the hypoglossal nerve: An anatomic study. Surg Radiol Anat 1998. [DOI: 10.1007/s00276-998-0109-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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290
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Abstract
Gliomatosis cerebri is a rare form of primary diffuse brain tumour first described by Nevin in 1938. It was originally considered to be a post-mortem diagnosis before Troost et al reported a clinically diagnosed case in 1987. However antemortem diagnosis remains difficult due to vague clinical symptoms and often non-specific findings on CT scanning. Gliomatosis cerebri has been classified by the World Health Organization as an infiltrative tumoural process, which involves at least two, and usually three, lobes of the brain. Magnetic resonance (MR) imaging shows a diffuse infiltrative process with possible mass effect but no necrosis. Histology is usually of a low grade astrocytic neoplasm which seemingly infiltrates out of proportion to the degree of anaplasia. We report two patients who presented over the past year, whose clinical and radiological features prompted a preoperative diagnosis of gliomatosis cerebri, confirmed by biopsy.
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291
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A glycine-rich RNA-binding protein gene is differentially expressed during acute hypersensitive response following Tobacco Mosaic Virus infection in tobacco. PLANT MOLECULAR BIOLOGY 1998; 37:571-6. [PMID: 9617823 DOI: 10.1023/a:1006031316476] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
During efforts for cloning disease resistance-responsive genes, a cDNA encoding a putative Nicotiana glutinosa glycine-rich RNA binding protein (ngRBP) was isolated from TMV induced cDNA library. Northern blot hybridization revealed that ngRBP gene is negatively regulated during early hours of TMV induced acute hypersensitive response (HR). Under greenhouse conditions induced expression of ngRBP gene was observed after 24 h following TMV infection. Salicylic acid and copper also induced ngRBP mRNA expression. Our findings are suggestive of some possible role for ngRBP in plant-pathogen interaction.
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292
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Abstract
The solution structure of cardiac troponin C (cTnC) (Sia, S., Li, M. X., Spyracopoulos, L., Gagne, S. M., Liu, W., Putkey, J. A. & Sykes, B. D. (1997) J. Biol. Chem. 272, 18216-18221) challenges existing structure/function models for this critical regulatory protein. For example, it is clear that the closed conformation of the regulatory N-terminal domain in Ca2+-bound cardiac troponin C (cTnC) presents a much different binding surface for Ca2+-sensitizing compounds than previously thought. We report here the use of Met methyl groups as site-specific structural markers to identify drug binding sites for trifluoperazine and bepridil on cTnC. Drug dependent changes in the NMR heteronuclear single-quantum coherence spectra of [methyl-13C]Met-labeled cTnC indicate that bepridil and trifluoperazine bind to similar sites but only in the presence of Ca2+. There are 3-4 drug binding sites in the N- and C-terminal domains of intact cTnC that exhibit fast exchange on the NMR time scale. Use of a novel spin-labeled phenothiazine and detection of isotope-filtered nuclear Overhauser effects allowed identification of drug binding sites in the shallow hydrophobic cup in the C-terminal domain and on two hydrophobic surfaces on the N-terminal regulatory domain. The data presented here, coupled with our previous study using covalent blocking groups, support a model in which the Ca2+-sensitizing binding site includes Met-45 in helix B of site I, and Met-60 and -80 in helices B and C of the regulatory site II. This subregion in cTnC makes a likely target against which to design new and selective Ca2+-sensitizing compounds.
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293
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Intracranial course and relations of the hypoglossal nerve. Surg Radiol Anat 1998. [DOI: 10.1007/bf01628913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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294
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Antagonizing excitotoxicity: a therapeutic strategy for stroke? THE MOUNT SINAI JOURNAL OF MEDICINE, NEW YORK 1998; 65:133-8. [PMID: 9520517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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295
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Endoscopic sigmoidopexy: a safer way to treat sigmoid volvulus? JOURNAL OF THE ROYAL COLLEGE OF SURGEONS OF EDINBURGH 1998; 43:64. [PMID: 9560517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Sigmoid volvulus may be treated by sigmoidoscopic reduction and elective sigmoidopexy or resection at a later stage, provided there is no evidence of peritonitis, perforation or rectal bleeding. However, operative treatment, whether urgent or elective, is associated with a relatively high morbidity and mortality. An endoscopic technique of sigmoidopexy is reported which is relatively quick and straightforward to perform, and is likely to have a lower rate of morbidity and mortality than conventional techniques for the treatment of sigmoid volvulus.
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296
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Abstract
This case report represents the finding of an abnormal atlas vertebra during dissection of 34 cadavers. The case which we describe appeared to have an atlas with a mass at a position similar to that of a centrum. This mass may have been a developmental abnormality of the centrum of the atlas or may have represented a congenital abnormality, known as the os odontoideum. Alternatively the abnormality may have been due to non-union of an odontoid fracture, with subsequent fusion to the atlas. The case report will discuss which of these three alternatives is more probable, and the embryology and phylogenesis of the atlas and axis, leading us to believe in a congenital hypothesis as an explanation for the malformation.
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297
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Evidence for autocrine inhibition of gonadotropin-releasing hormone (GnRH) gene transcription by GnRH in hypothalamic GT1-1 neuronal cells. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1997; 50:51-8. [PMID: 9406917 DOI: 10.1016/s0169-328x(97)00171-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
To examine whether an ultrashort feedback mechanism of gonadotropin-releasing hormone (GnRH) operates at the level of gene transcription, we studied the effects of GnRH analogs on GnRH promoter activity and GnRH mRNA level in hypothalamic GT1-1 neuronal cells. Treatment of GT1-1 cells with buserelin, a GnRH agonist, or native GnRH for 24 h significantly decreased GnRH promoter activity and its mRNA level, whereas that with GnRH antagonists, antide or [D-Phe2,D-Ala6]-GnRH, showed no effect. The inhibitory effects of buserelin on GnRH gene transcription and GnRH mRNA level were dose-related, and a significant inhibition was observed in cells treated with buserelin at concentrations higher than 0.1 microM. Time-course experiments showed that significant decreases in GnRH promoter-driven luciferase activity and GnRH mRNA level were observed within 12 h and sustained up to 48 h. Moreover, treatment with GnRH agonist for 12 h significantly decreased the transcription rate of the mouse GnRH gene, as revealed by nuclear run-on transcription assay. The promoter analysis with the 5'-deletional constructs demonstrated that cis-acting elements important for GnRH autoregulation by GnRH agonist reside within -854 bp upstream from the transcription start site. These data clearly demonstrate that GnRH can exert autocrine regulation at the level of GnRH gene transcription.
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298
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Abstract
Galectin-1 is a member of beta-galactoside-binding lectins expressed in a variety of mammalian tissues. We report here that galectin-1 mRNA is abundantly expressed in the mouse reproductive organs such as the uterus and ovary. Uterine expression of galectin-1 mRNA is specifically regulated in the embryonic implantation process. Its expression increased at a high level on the fifth day post coitum (dpc 5) when embryos hatched into the endometrial epithelial cells. In the absence of embryos, however, galectin-1 expression in the mouse uterus decreased on dpc 5. In the delayed implantation mice, galectin-1 mRNA levels was augmented by the termination of the delay of implantation. Ovarian steroids progesterone and estrogen differentially regulated galectin-1 mRNA level in uterine tissues. Treatment with RU486, a progesterone receptor antagonist, blocked progesterone-induced galectin-1 mRNA level in uterine tissues of ovariectomized mouse. ICI182780, a pure estrogen receptor antagonist, clearly blocked the estrogen effect. Taken together, galectin-1 gene expression in the uterine tissues was regulated by ovarian steroids and this regulation correlated with the implantation process.
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299
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Abstract
Laminin may be involved in uterine re-organization and embryo attachment to the uterine wall during the peri-implantation period. In the present study using a competitive reverse transcription-polymerase chain reaction (RT-PCR), the precise expression patterns of laminin chain (A, B1, and B2)-specific mRNAs were examined in mouse uterine tissues during the peri-implantation period. Although Northern blot hybridization failed to detect laminin A chain mRNA in mouse uterus, RT-PCR analysis showed that laminin A chain mRNA was present even at the lower level compared with B1 and B2 chain mRNA levels. Competitive RT-PCR revealed that approximately 3 x 10(6), 3.6 x 10(7), and 4 x 10(8) copies of A, B1, and B2 chain mRNA transcripts were present in 1 microgram of total RNA isolated from the uterus. During pregnancy, the A chain mRNA level was significantly increased only from day 6 after post-hCG when embryo attachment and decidualization started. Elevated level of A chain mRNA was sustained thereafter. Laminin A chain mRNA synthesized at this period was mainly originated from stroma decidual cells. The discrete elevation of laminin A chain mRNA level was also observed after estrogen stimulation in the delayed implantation model. Estrogenic stimulation to ovariectomized, progesterone-treated pregnant mice resulted in about a three-fold increase of laminin A chain mRNA levels. In contrast to A chain mRNA, both B1 and B2 chain mRNA levels were insignificantly altered during the peri-implantation period and delayed implantation by an estrogenic stimulation. Taken together, our results for the first time demonstrate that: (1) laminin A chain mRNA as well as B chain mRNAs is expressed in mouse uterus, (2) its mRNA level is significantly increased along with implantation process, and (3) ovarian steroids, especially estrogen, are likely to be involved in the regulation of laminin gene expression in the uterus.
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300
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Abstract
OBJECTIVE Switching from two-lung to one-lung ventilation would be expected to have large effects on lung mechanical properties, and these effects may depend on tidal volume and respiratory frequency. These changes in lung mechanics with one-lung ventilation may be similar to pulmonary edema. Deteriorating lung mechanics during pulmonary edema have been attributed to a loss of ventilated lung units. Therefore, changes in lung mechanics caused by one-lung ventilation were measured and compared with those previously seen during pulmonary edema. DESIGN Prospective study. SETTING Research laboratory. INTERVENTIONS After induction of anesthesia, beagle dogs' tracheas were intubated with an endotracheal tube with a bronchial blocker (Univent System Corp, Tokyo, Japan) to apply one-lung ventilation. The proper position of the bronchial blocker during one-lung ventilation was confirmed with a fiberoptic bronchoscope. MEASUREMENTS AND MAIN RESULTS Lung elastance (EL) and resistance (RL) were calculated from measurements of airway pressure, esophageal pressure, and airway flow in five anesthetized, paralyzed dogs during sinusoidal forcing at a constant mean airway pressure of 10 cmH2O in a wide range of breathing frequencies (0.2 to 1.0 Hz in intervals of 0.2) and tidal volumes (50, 100, 200, and to 300 mL). Measurements were made before and after the left mainstem bronchus was occluded with the bronchial blocker. During ventilation of both lungs, EL and RL depended relatively little on frequency, and both EL and RL were independent of tidal volume. During one-lung ventilation, EL doubled and, at most frequencies, RL increased; frequency dependences were not increased, and no dependence on tidal volume was observed. CONCLUSIONS The lack of tidal volume dependence in EL and lack of large-frequency dependence in RL during one-lung ventilation are inconsistent with changes induced by severe pulmonary edema. Although decreases in ventilatable lung volume may contribute to increases in lung elastance, other characteristics of mechanical behavior during one-lung ventilation differ from those of pulmonary edema; therefore, other additional mechanisms must be involved in determining lung mechanical properties during severe pulmonary edema.
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