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1.
BMJ Mil Health ; 167(3): 187-191, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34021066

ABSTRACT

INTRODUCTION: According to data released by the Korea National Statistical Office, the number of accidents has been decreasing since 2012. However, a considerable number of deaths related to safety accidents (23-46 deaths) are still reported annually. This study aimed to observe the correlation between accident prevention activities in the Republic of Korea (ROK) military and the incidence of safety accidents. METHODS: The study used data from the 2014-2015 Military Health Survey and included 13 618 responses (Army: 8414 (61.8%); Navy/Marine: 2262 (16.6%); Air Force: 2942 (21.6%)) from the ROK military personnel. Accident experiences and thoughts on accident prevention activities were self-reported. Multiple logistic regression analysis was used to examine the validity of accident prevention activity and accident experience. RESULTS: Of the 13 618 military personnel who responded, 12.0% reported experiencing safety accidents in the military and 1020 (7.5%) felt that accident prevention activities in the military were insufficient. On logistic regression analysis, we found a significant difference (insufficiency OR=1.56, CI 1.31 to 1.86). In particular, military personnel who belong to the Army and Navy were more likely to think that accident prevention activities were insufficient. In addition, military personnel who experienced falls/slips, crash, and laceration/puncture wound/amputation/penetrating wound accidents were more likely to think accident prevention activities were insufficient. CONCLUSIONS: Our study found that accident prevention activities in the military and accident experiences were related. It is necessary for the ROK Ministry of Defense, Army, Navy and Air Force headquarters to re-evaluate their accident prevention systems.


Subject(s)
Accident Prevention/methods , Military Medicine/methods , Preventive Medicine/methods , Accident Prevention/trends , Adult , Cross-Sectional Studies , Female , Humans , Incidence , Logistic Models , Male , Middle Aged , Military Medicine/trends , Preventive Medicine/trends , Republic of Korea , Risk Factors , Self Report , Surveys and Questionnaires
2.
BMJ Mil Health ; 167(6): 398-401, 2021 Dec.
Article in English | MEDLINE | ID: mdl-32139412

ABSTRACT

INTRODUCTION: The easiest way to prevent noise-induced hearing loss (NIHL) is to wear earplugs. The Republic of Korea (ROK) Ministry of National Defense (MND) is supplying earplugs to prevent NIHL, but many patients still suffer from this. We speculated that earplugs would have a high NIHL rate, depending on the rate of use of earplugs, regardless of the rate of supply. Therefore, we conducted this study to investigate the relationship between the use of earplugs and hearing loss by ROK military personnel. METHODS: The study used data from the Military Health Survey conducted in 2014-2015, which included 13 470 questionnaires completed by ROK military personnel. Hearing loss and earplug use were self-reported. Logistic regression analysis was used to assess associations between earplug use and hearing loss. RESULTS: The study sample included 13 470 ROK military personnel (response rate of 71.2%) (Army, 8330 (61.8%); Navy/Marines, 2236 (16.6%); and Air Force, 2904 (21.6%)). Overall, 18.8% of Korean military personnel reported that they always wore earplugs, and 2.8% reported hearing loss. In logistic regression analysis, there were significant differences in the rates of hearing loss associated with wearing earplugs sometimes (OR=1.48, 95% CI 1.07 to 2.05) and never wearing earplugs (OR=1.53, 95% CI 1.12 to 2.10). In subgroup analysis, in Air Force, non-combat branch, forward area and long-term military service personnel increased hearing loss was associated with not wearing earplugs. CONCLUSION: Our study confirmed that within the ROK military, there is an association between hearing loss and lack of earplug use. In the ROK MND, Army, Navy/Marines and Air Force headquarters must provide guidelines for the use of earplugs during field training to protect military personnel's hearings and, if necessary, need to be regulated or institutionalised.


Subject(s)
Hearing Loss, Noise-Induced , Military Personnel , Ear Protective Devices , Hearing , Hearing Loss, Noise-Induced/epidemiology , Humans , Republic of Korea/epidemiology
3.
Ultramicroscopy ; 197: 28-38, 2019 02.
Article in English | MEDLINE | ID: mdl-30476703

ABSTRACT

Cathodoluminescence (CL) spectroscopy provides a powerful way to characterize optical properties of materials with deep-subwavelength spatial resolution. While CL imaging to obtain optical spectra is a well-developed technology, imaging CL lifetimes with nanoscale resolution has only been explored in a few studies. In this paper we compare three different time-resolved CL techniques and compare their characteristics. Two configurations are based on the acquisition of CL decay traces using a pulsed electron beam that is generated either with an ultra-fast beam blanker, which is placed in the electron column, or by photoemission from a laser-driven electron cathode. The third configuration uses measurements of the autocorrelation function g(2) of the CL signal using either a continuous or a pulsed electron beam. The three techniques are compared in terms of complexity of implementation, spatial and temporal resolution, and measurement accuracy as a function of electron dose. A single sample of InGaN/GaN quantum wells is investigated to enable a direct comparison of lifetime measurement characteristics of the three techniques. The g(2)-based method provides decay measurements at the best spatial resolution, as it leaves the electron column configuration unaffected. The pulsed-beam methods provide better detail on the temporal excitation and decay dynamics. The ultra-fast blanker configuration delivers electron pulses as short as 30 ps at 5 keV and 250 ps at 30 keV. The repetition rate can be chosen arbitrarily up to 80 MHz and requires a conjugate plane geometry in the electron column that reduces the spatial resolution in our microscope. The photoemission configuration, pumped with 250 fs 257 nm pulses at a repetition rate from 10 kHz to 25 MHz, allows creation of electron pulses down to a few ps, with some loss in spatial resolution.

4.
Ultramicroscopy ; 187: 1-12, 2018 04.
Article in English | MEDLINE | ID: mdl-29413406

ABSTRACT

A strain characterization technique based on Moiré interferometry in a scanning transmission electron microscope (STEM) and geometrical phase analysis (GPA) method is demonstrated. The deformation field is first captured in a single STEM Moiré hologram composed of multiple sets of periodic fringes (Moiré patterns) generated from the interference between the periodic scanning grating, fixing the positions of the electron probe on the sample, and the crystal structure. Applying basic principles from sampling theory, the Moiré patterns arrangement is then simulated using a STEM electron micrograph reference to convert the experimental STEM Moiré hologram into information related to the crystal lattice periodicities. The GPA method is finally applied to extract the 2D relative strain and rotation fields. The STEM Moiré interferometry enables the local information to be de-magnified to a large length scale, comparable to what can be achieved in dark-field electron holography. The STEM Moiré GPA method thus extends the conventional high-resolution STEM GPA capabilities by providing comparable quantitative 2D strain mapping with a larger field of view (up to a few microns).

5.
Eur J Vasc Endovasc Surg ; 53(2): 158-167, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27592735

ABSTRACT

OBJECTIVE: To evaluate treatment outcomes of in situ abdominal aortic reconstruction with cryopreserved arterial allograft (CAA) for patients with abdominal aortic infection. MATERIALS AND METHODS: A retrospective review of prospectively collected data was conducted of patients who underwent in situ aortic reconstruction using CAA for primary, secondary, or prosthetic infection of the abdominal aorta between May 2006 and July 2015, at a single institution. Clinical presentation, indications for treatment, procedural details, early post-operative mortality and morbidity, late death, and graft related complications during the follow up period were investigated. Patient survival and event free survival (any death or re-operation) were calculated using the Kaplan-Meier method. RESULTS: Twenty-five patients (male, n = 20, 80%; mean age, 70.2 ± 8.7 years) underwent in situ abdominal aortic reconstruction (48% aortic, 52% aorto-bi-iliac) with vessel size and ABO matched CAA for treatment of abdominal aortic infection caused by infected abdominal aortic aneurysm (n = 15), aortic prosthesis infection (n = 7), aortic reconstruction with concomitant colon resection (n = 2), and primary suppurative aortitis (n = 1). The median follow up was 19.1 months (range 1-73 months). There were seven post-operative deaths including two (8%) early (<30 days) and five (20%) late deaths There were three (12%) graft related complications including thrombotic occlusion of the CAA, aneurysmal dilatation, and aorto-enteric fistula. Three years after CAA implantation, patient survival was 74% and the event free survival was 58%. CONCLUSIONS: It is believed that in situ abdominal aortic reconstruction with CAA is a useful option for treating primary, secondary, or prosthetic infection of the abdominal aorta.


Subject(s)
Aorta, Abdominal/surgery , Bioprosthesis , Blood Vessel Prosthesis Implantation/instrumentation , Blood Vessel Prosthesis , Cryopreservation , Prosthesis-Related Infections/surgery , Aged , Aged, 80 and over , Allografts , Aorta, Abdominal/diagnostic imaging , Aorta, Abdominal/microbiology , Aortography/methods , Blood Vessel Prosthesis Implantation/adverse effects , Blood Vessel Prosthesis Implantation/mortality , Computed Tomography Angiography , Databases, Factual , Disease-Free Survival , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Postoperative Complications/etiology , Postoperative Complications/surgery , Prosthesis Design , Prosthesis-Related Infections/diagnostic imaging , Prosthesis-Related Infections/microbiology , Prosthesis-Related Infections/mortality , Retrospective Studies , Risk Factors , Time Factors , Treatment Outcome
6.
Nano Lett ; 15(12): 7801-7, 2015 Dec 09.
Article in English | MEDLINE | ID: mdl-26539880

ABSTRACT

We report on the molecular beam epitaxial growth and structural characterization of self-organized AlGaN nanowire arrays on Si substrate with high luminescence efficiency emission in the deep ultraviolet (UV) wavelength range. It is found that, with increasing Al concentration, atomic-scale compositional modulations can be realized, leading to three-dimensional quantum confinement of charge carriers. By further exploiting the Anderson localization of light, we have demonstrated, for the first time, electrically injected AlGaN lasers in the deep UV band operating at room temperature. The laser operates at ∼289 nm and exhibits a threshold of 300 A/cm(2), which is significantly smaller compared to the previously reported electrically injected AlGaN multiple quantum well lasers.

7.
Genet Mol Res ; 14(3): 8420-30, 2015 Jul 28.
Article in English | MEDLINE | ID: mdl-26345769

ABSTRACT

We observed 3 types of non-parental banding patterns using simple-sequence repeat primers in a recombinant inbred line maize population developed from 2 inbred lines, Mo17 and KW7. We observed alleles that were not present in either of the parents, known as non-parental alleles. Although non-parental alleles are a consequence of genetic variation, they are less common in progenies derived from inbred lines. Generally, when non-parental alleles are encountered during genotyping analysis, they are either deleted from the analysis or considered to be missing data. However, before making a decision regarding how to treat non-parental alleles, it is important to understand the mechanism through which they form. There are a variety of potential reasons for the formation of non-parental bands, including recombination or mutation in the simple-sequence repeat region, residual heterozygosity in parental lines, or chromosomal aberrations resulting from rearrangements and transposons. In this article, we discuss the potential reasons behind the formation of the non-parental alleles observed in our data.


Subject(s)
Zea mays/genetics , Alleles , Chromosome Banding , DNA Transposable Elements/genetics , Gene Rearrangement , Genetic Variation/genetics , Inbreeding , Microsatellite Repeats , Polymorphism, Genetic , Recombination, Genetic
8.
Mucosal Immunol ; 8(4): 930-42, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25563499

ABSTRACT

Eosinophils are multifunctional leukocytes that reside in the gastrointestinal (GI) lamina propria, where their basal function remains largely unexplored. In this study, by examining mice with a selective deficiency of systemic eosinophils (by lineage ablation) or GI eosinophils (eotaxin-1/2 double deficient or CC chemokine receptor 3 deficient), we show that eosinophils support immunoglobulin A (IgA) class switching, maintain intestinal mucus secretions, affect intestinal microbial composition, and promote the development of Peyer's patches. Eosinophil-deficient mice showed reduced expression of mediators of secretory IgA production, including intestinal interleukin 1ß (IL-1ß), inducible nitric oxide synthase, lymphotoxin (LT) α, and LT-ß, and reduced levels of retinoic acid-related orphan receptor gamma t-positive (ROR-γt(+)) innate lymphoid cells (ILCs), while maintaining normal levels of APRIL (a proliferation-inducing ligand), BAFF (B cell-activating factor of the tumor necrosis factor family), and TGF-ß (transforming growth factor ß). GI eosinophils expressed a relatively high level of IL-1ß, and IL-1ß-deficient mice manifested the altered gene expression profiles observed in eosinophil-deficient mice and decreased levels of IgA(+) cells and ROR-γt(+) ILCs. On the basis of these collective data, we propose that eosinophils are required for homeostatic intestinal immune responses including IgA production and that their affect is mediated via IL-1ß in the small intestine.


Subject(s)
Eosinophils/immunology , Eosinophils/metabolism , Homeostasis , Immunoglobulin A/biosynthesis , Interleukin-1beta/metabolism , Intestine, Small/immunology , Intestine, Small/metabolism , Adoptive Transfer , Animals , Cell Count , Gastrointestinal Microbiome , Gene Expression , Immune Tolerance , Immunoglobulin A, Secretory/biosynthesis , Interleukin-1beta/genetics , Intestinal Mucosa/immunology , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Intestine, Small/microbiology , Lymphotoxin-alpha/genetics , Lymphotoxin-beta/genetics , Mice , Mice, Knockout , Mucus/metabolism , Peyer's Patches/immunology , Peyer's Patches/metabolism , Plasma Cells/immunology , Plasma Cells/metabolism
9.
Br J Surg ; 100(13): 1756-63, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24227361

ABSTRACT

BACKGROUND: The aim of this study was to identify risk factors for invasive breast cancer in patients diagnosed with ductal carcinoma in situ (DCIS) on a preoperative biopsy. These factors were used to develop a nomogram for predicting the risk of invasion in the preoperative setting. METHODS: This was a retrospective analysis of patients who underwent surgical treatment for DCIS diagnosed before surgery between 1997 and 2009. Multivariable analysis was used to identify clinical, radiological and histopathological factors that may predict upstaging. A nomogram was developed to predict the probability of invasion using multiple logistic regression analysis. This nomogram was subsequently validated using another cohort of patients with a preoperative diagnosis of DCIS between 2010 and 2012. RESULTS: Upstaging to invasive cancer occurred in 123 (24.9 per cent) of 493 women treated between 1997 and 2009. A larger DCIS lesion (at least 15 mm), lack of hormone receptor expression, intermediate or high nuclear grade, diagnosis on core biopsy compared with vacuum-assisted biopsy, and non-cribriform subtype of DCIS were significantly associated with upstaging. A nomogram developed using these factors demonstrated good predictive performance (area under the receiver operating characteristic (ROC) curve (AUC) 0·823, 95 per cent confidence interval 0·787 to 0·860). The nomogram showed similar predictive performance in the validation data set, based on another 149 women (AUC 0·700, 0·613 to 0·786). CONCLUSION: Upstaging to invasive cancer in women with a preoperative diagnosis of DCIS is common. A nomogram based on the five most significant factors related to upstaging accurately predicted invasive cancer. This nomogram may be useful when deciding whether to pursue axillary staging with sentinel lymph node biopsy in patients with DCIS.


Subject(s)
Breast Neoplasms/pathology , Carcinoma, Intraductal, Noninfiltrating/pathology , Nomograms , Adult , Aged , Aged, 80 and over , Biopsy, Needle/methods , Breast Neoplasms/surgery , Carcinoma, Intraductal, Noninfiltrating/surgery , Female , Humans , Middle Aged , Neoplasm Invasiveness/pathology , Neoplasm Staging/methods , Preoperative Care/methods , ROC Curve , Retrospective Studies , Risk Factors , Young Adult
10.
Rev Sci Instrum ; 82(7): 075111, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21806231

ABSTRACT

Ultrasonic sensors of 500 kHz frequency have been used to study the measuring of gas pressure in the range 1.33 × 10(3)-2.026 × 10(5) Pa. From the experimental data it was observed that amplitude of the transmitted ultrasound was dependent on gas pressure. The results confirm that by using appropriate instruments including sensors and electronic devices, pressure of the gas can be successfully measured by measuring the magnitude of the received signal. The proposed method is expected to be applied to develop as new vacuum pressure measurement instrument.

11.
Int J Lab Hematol ; 30(2): 139-48, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18333846

ABSTRACT

The pattern of leukocyte locomotion can be changed in many pathological situations, but its accurate analysis is difficult because of technological limitation. In the present study, by using a newly developed time-lapse videomicroscopic technique, we have analyzed the locomotive patterns of leukocytes in a stable concentration gradient of chemokines. Granulocytes, monocytes, and lymphocytes were purified from adult human peripheral blood. Locomotive behavior of the leukocytes was analyzed by an optical assay using a microchannel producing a stable concentration gradient of chemokines. Videomicroscopic analysis showed distinct locomotive patterns of granulocytes, monocytes, and lymphocytes. Granulocytes were intrinsically motile, vigorously moving in random direction without any chemokine stimulation. Upon stimulation with CXCL8/IL-8, the speed of migration was increased from 13.3 +/- 2.8 to 19.4 +/- 2.5 microm/min (P = 0.002, n = 100) and they moved toward the chemokine, although many cells still wandered very much. Stimulation with CCL5/RANTES or CXCL12/SDF-1alpha induced similar changes in locomotive pattern. On the other hand, most lymphocytes did not polarize or move spontaneously without chemokine stimulation. Stimulation with CXCL12 induced directional migration in 37% of the lymphocytes at a speed of 9.6 +/- 1.6 microm/min (n = 100). The movement pattern of monocytes was similar to that of granulocytes in that they tend to become polarized and move spontaneously, but they moved at a very slow speed ranging from 3.9 to 4.2 microm/min even with chemokine stimulation. The new optical assay may be useful for many diagnostic as well as basic studies.


Subject(s)
Chemokines/physiology , Chemotaxis, Leukocyte , Granulocytes/physiology , Lymphocytes/physiology , Monocytes/physiology , Adult , Humans , Receptors, Chemokine/metabolism
12.
Cytotherapy ; 9(5): 451-8, 2007.
Article in English | MEDLINE | ID: mdl-17786606

ABSTRACT

BACKGROUND: Mesenchymal stromal cells (MSC) comprise one of the BM stromal cells that are known to support hematopoiesis. It has also been suggested recently that MSC display immunosuppressive capacities through inhibiting the differentiation of monocyte-derived DC. DC travel to the lymph nodes (LN) to present Ag to T cells, and CCL21 is the chemokine that plays an important role in DC migration into the T-cell area of LN. We addressed the effect of MSC on this chemotactic activity of DC, one of the typical characteristics upon maturation. METHODS: BM cells were isolated and then cultured for generation of myeloid DC in the presence of GM-CSF and/or lipopolysaccharide with or without MSC. MSC were identified by flow cytometry of the immunologic markers and by performing colony-forming unit fibroblast assay. Migration of DC was observed with a newly developed time-lapse video microscopic technique. RESULTS: MSC co-culture inhibited the initial differentiation of DC, as well as their maturation. The matured DC actively migrated directionally in response to CCL21, a powerful DC-attracting chemokine, whereas the MSC co-cultured DC did not. DISCUSSION: Collectively, the findings of these experiments raise the possibility that MSC suppress the migratory function of DC and so they may serve immunoregulatory activities through the modulation of the Ag-presenting function of DC.


Subject(s)
Cell Communication/immunology , Cell Differentiation/immunology , Cell Movement/immunology , Dendritic Cells/immunology , Mesenchymal Stem Cells/immunology , Stromal Cells/immunology , Animals , Cells, Cultured , Chemokine CCL21 , Chemokines, CC/immunology , Coculture Techniques , Dendritic Cells/cytology , Immune Tolerance/immunology , Mesenchymal Stem Cells/cytology , Mice , Mice, Inbred C57BL , RNA, Messenger/metabolism , Receptors, CCR1 , Receptors, Chemokine/genetics , Receptors, Chemokine/immunology , Stromal Cells/cytology
13.
Ann Trop Med Parasitol ; 97(4): 339-44, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12831519

ABSTRACT

One of the peculiar features of Plasmodium vivax malaria in South Korea is the surprisingly high frequency of thrombocytopenia. The mechanism by which this malaria-related thrombocytopenia develops and its role in the pathology and progress of human infection with P. vivax have not yet been completely understood. In the present study, the serum cytokine profiles of cases of P. vivax malaria who presented with thrombocytopenia were compared with those of similar cases who did not have thrombocytopenia at presentation. The subjects were the 94 consecutive cases of P. vivax malaria who presented at five hospitals in South Korea (all near the Demilitarized Zone) between May 2000 and October 2002, 47 of whom had thrombocytopenia at presentation. When mean values and (S.E.) were compared, the thrombocytopenic patients were found not only to be generally older than the non-thrombocytopenic [25.3 (1.1) v. 21.3 (0.18) years; P < 0.001] but also to have presented with higher serum concentrations of aspartate aminotransferase [77.6 (16.6) v. 32.3 (7.4) U/litre; P < 0.0001], alanine aminotransferase [96.7 (19.0) v. 44.7 (12.0) U/litre; P = 0.0001], interleukin-1 [49.9 (7.4) v. 23.7 (5.1) pg/ml; P < 0.001], interleukin-6 [174.9 (26.4) v. 57.3 (14.6) pg/ml; P = 0.001], interleukin-10 [308.2 (39.6) v. 137.9 (23.1) pg/ml; P < 0.002] and transforming growth factor-beta [1134.3 (387.5) v. 416.6 (183.8) pg/ml; P < 0.0001], and higher levels of parasitaemia [4345.7 (966.6) v. 1443.8 (222.7) parasites/microl; P = 0.03). The non-thrombocytopenic patients, however, had relatively high total leucocyte counts [5.8 (0.24) v. 5.4 (0.66) leucocytes/nl; P = 0.03]. The thrombocytopenia associated with P. vivax malaria in South Korea therefore appears to be associated with elevated serum concentrations of both pro- and anti-inflammatory cytokines. To define the role of each cytokine in the development of thrombocytopenia during the course of acute P. vivax malaria, further prospective studies are needed.


Subject(s)
Cytokines/blood , Interleukins/blood , Malaria, Vivax/blood , Thrombocytopenia/blood , Adult , Alanine Transaminase/blood , Aspartate Aminotransferases/blood , Enzyme-Linked Immunosorbent Assay , Female , Humans , Interleukin-6/blood , Malaria, Vivax/complications , Male , Retrospective Studies , Thrombocytopenia/complications
14.
Ann Hematol ; 82(5): 278-83, 2003 May.
Article in English | MEDLINE | ID: mdl-12679887

ABSTRACT

Erythropoietin (EPO) induces erythropoiesis in vitro as well as in vivo, and the process of erythroid differentiation has been explored phenotypically and morphologically. However, morphological analysis of in vitro erythropoiesis of human hematopoietic progenitor cells at the ultrastructural level has not been reported before. In the present study, we have traced the ultrastructural changes of erythroid differentiation during ex vivo expansion of human cord blood (CB) CD34(+) cells in the presence of EPO by electron microscopy (EM), along with concurrent phenotypic analysis. CD34(+) cells purified from ten CBs by immunomagnetic selection were cultured in serum-free essential media in the presence of a combination of the several cytokines including EPO, thrombopoietin, flt3-ligand (FL), stem cell factor (SCF), granulocyte colony-stimulating factor, interleukin (IL)-3 and/or IL-11. Phenotypic analysis was performed by flow cytometric analysis for erythroid markers, including glycophorin C (GPC), Kell-related, glycophorin A (GPA), band 3, Lu(b), and RhD. Ultrastructural analysis was performed by electron-microscopic examination of the cultured cells stained with uranyl acetate and lead citrate. Phenotypic analysis revealed that in the absence of EPO, genuine erythroid fraction expressing the typical pattern of erythroid markers did not appear. The order of the above markers expressed in the cultured cells in the presence of EPO was GPC, Kell-related, GPA, band 3, Lu(b), and RhD, irrespective of the type of cytokine added. Of the cytokines used in combination with EPO, FL + IL-3 was the most efficient in inducing erythroid differentiation, which was followed by SCF + IL-3. EM examination demonstrated complete process of erythroid development from pronormoblasts to reticulocytes with nuclei having been extruded and mature erythrocytes. These results suggest that morphologically intact erythrocytes could be produced by ex vivo expansion of CB CD34(+) cells using EPO.


Subject(s)
Antigens, CD34 , Erythroid Precursor Cells/cytology , Erythropoiesis , Cell Culture Techniques , Cell Differentiation , Cytokines/pharmacology , Erythroid Precursor Cells/immunology , Erythroid Precursor Cells/ultrastructure , Fetal Blood , Flow Cytometry , Humans , Immunophenotyping , Microscopy, Electron
15.
Arch Virol ; 147(2): 229-42, 2002.
Article in English | MEDLINE | ID: mdl-11890521

ABSTRACT

Increased gelatinolytic activity was observed in respiratory syncytial virus (RSV)-infected HEp-2 cells by using zymography. The anti-matrix metalloproteinase-9 (MMP-9) antibody specifically reduced the gelatinolytic activity suggesting that the increased gelatinolytic activity was due to the MMP-9. It was also supported by the results from immunofluorescent staining, treatment of MMP inhibitors, and RSV infection of the cell clones that were transfected with plasmids to express more MMP-9 and tissue type inhibitor of metalloproteinase-1 (TIMP-1). The gelatinolytic activity of extracellular MMP-9 in RSV-infected HEp-2 cells increased 1.5 +/- 0.2 fold compared with the control (p < 0.01). Cell surface MMP-9 expression was also clearly detected by immunofluorescent staining. Treatment with 1,10-phenanthroline (0.05 mM), ethylenediamine-tetraacetate (EDTA) (1.5 mM), and penta-O-galloyl-beta-D-glucose (PGG) (3.3 microM) inhibited RSV multiplication as well as syncytia formation. Furthermore, the average syncytia size increased when the cells expressing more MMP-9 were infected by RSV. In contrast, syncytia formation was inhibited in the cells manipulated to express TIMP-1. Thus, this study concludes that although RSV infection induces MMP-9, which can enhance the syncytia formation leading to RSV multiplication and spread it can be inhibited by MMP inhibitors.


Subject(s)
Epithelial Cells/metabolism , Matrix Metalloproteinase 9/metabolism , Respiratory Syncytial Virus Infections/virology , Respiratory Syncytial Viruses/pathogenicity , Epithelial Cells/virology , Giant Cells/physiology , Humans , Matrix Metalloproteinase 9/genetics , Matrix Metalloproteinase Inhibitors , Respiratory Syncytial Viruses/physiology , Tissue Inhibitor of Metalloproteinase-1/genetics , Tissue Inhibitor of Metalloproteinase-1/metabolism , Transfection , Tumor Cells, Cultured , Virus Replication
16.
Scand J Immunol ; 55(1): 88-95, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11841696

ABSTRACT

Thrombopoietin (TPO) is one of the most promising stimulants for ex vivo expansion of haematopoietic stem cells. Previously, we have found that TPO induces a characteristic pattern of apoptosis during ex vivo expansion of human cord blood (CB) CD34+ cells and that the TPO-induced apoptotic cells belong to megakaryocyte (MK) lineage. In this study, we have examined the maturation of MK and platelet production in association with the TPO-induced apoptosis. CD34+ cells, purified from human CB, were expanded in serum-free conditions stimulated with TPO. Apoptosis was confirmed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labelling (TUNEL) assay and electron microscopy (EM). Simultaneous measurement of DNA content and immunophenotyping revealed that the cells with higher DNA content (>8 N) constituted less than 5% of the CD41+ fractions until day 14, implying premature apoptosis of MKs before full polyploidization. Nevertheless, EM observation showed not only platelet territories but also newly produced platelets in which granules and microfilaments could be identified. Furthermore, flow cytometry demonstrated that the platelet fraction expressed P-selectin and an activation motif on GPIIb/IIIa recognized by monoclonal antibody PAC-1 upon stimulation with adenosine diphosphate (ADP). In addition, periodic acid-Schiff (PAS)-positive materials and nonspecific esterase activities could be demonstrated. Therefore, it is suggested that platelet production and the accompanying processes, rather than apoptosis only, be hastened during the ex vivo expansion of CB CD34+ cells when using TPO.


Subject(s)
Antigens, CD34/metabolism , Fetal Blood/cytology , Hematopoiesis/drug effects , Megakaryocytes/cytology , Megakaryocytes/drug effects , Thrombopoietin/pharmacology , Apoptosis/drug effects , Blood Platelets/cytology , Blood Platelets/drug effects , Blood Platelets/immunology , Cell Differentiation/drug effects , Hematopoietic Stem Cells/cytology , Hematopoietic Stem Cells/drug effects , Hematopoietic Stem Cells/immunology , Humans , In Vitro Techniques , Infant, Newborn , Megakaryocytes/immunology , Microscopy, Electron
17.
Int J Radiat Oncol Biol Phys ; 51(3): 589-98, 2001 Nov 01.
Article in English | MEDLINE | ID: mdl-11597797

ABSTRACT

PURPOSE: To evaluate the long-term outcome and prognostic factors in patients with skull base erosion from nasopharyngeal carcinoma after initial radiotherapy (RT). METHODS AND MATERIALS: From January 1985 to December 1986, 100 patients (71 males, 29 females) with a diagnosis of nasopharyngeal carcinoma were found on computed tomography (CT) to have skull base erosion. The mean age was 41 years (range 16-66). Ninety-six patients had World Health Organization type III undifferentiated carcinoma, and 4 had type I. The metastatic workup, including chest radiography, liver ultrasound scanning, and liver function test was negative. All patients underwent external beam RT (EBRT) alone to 66-80 Gy during 6-8 weeks. A daily fraction size of 2 Gy was delivered using 60Co or a linear accelerator. No patient received chemotherapy. All patients were followed at regular intervals after irradiation. The median follow-up was 22.3 months (range 2-174). Survival of the cohort was computed by the Kaplan-Meier method. The potential prognostic factors of survival were examined. Multivariate analyses were performed using the Cox regression model. RESULTS: The 1, 2, 5, and 10-year overall survival rate for the cohort was 79%, 41%, 27%, and 13%, respectively. However, the subgroup of patients with both anterior cranial nerve (I-VIII) and posterior cranial nerve (IX-XII) involvement had a 5-year survival of only 7.7%. A difference in the time course of local recurrence and distant metastasis was observed. Both local recurrence and distant metastasis often occurred within the first 2 years after RT. However, local relapse continued to occur after 5 years. In contrast, no additional distant metastases were found after 5 years. The causes of death included local recurrence (n = 59), distant metastasis (n = 21), both local recurrence and distant metastasis (n = 1), and unrelated causes (n = 5). After multivariate analysis, complete recovery of cranial nerve involvement, cranial nerve palsy, and headache after irradiation were found to be independent prognostic factors in this cohort. CONCLUSIONS: We present one of the longest follow-ups of patients with nasopharyngeal carcinoma invading the skull base. Our results demonstrate the importance of cranial nerve involvement, recovery of headache, and cranial nerve palsy. These factors should be carefully evaluated from the history, physical examination, and imaging studies. A subgroup of patients with skull base involvement had long-term survival after RT alone. The findings of this study are important as a yardstick against which more aggressive strategies, such as combined radiochemotherapy and altered fractionation RT can be compared.


Subject(s)
Nasopharyngeal Neoplasms/pathology , Nasopharyngeal Neoplasms/radiotherapy , Skull Base Neoplasms/pathology , Adolescent , Adult , Aged , Analysis of Variance , Female , Follow-Up Studies , Humans , Male , Middle Aged , Nasopharyngeal Neoplasms/mortality , Neoplasm Invasiveness , Neoplasm Recurrence, Local/mortality , Neoplasm Staging , Prognosis , Proportional Hazards Models , Skull Base/pathology , Skull Base Neoplasms/mortality , Time Factors
18.
Int J Radiat Oncol Biol Phys ; 51(3): 605-13, 2001 Nov 01.
Article in English | MEDLINE | ID: mdl-11597799

ABSTRACT

PURPOSE: To report the preliminary results of a Phase I/II study combining radiotherapy and in situ gene therapy (adenovirus/herpes simplex virus thymidine kinase gene/valacyclovir) with or without hormonal therapy in the treatment of prostate cancer. METHODS AND MATERIALS: Arm A: low-risk patients (T1-T2a, Gleason score <7, pretreatment PSA <10) were treated with combined radio-gene therapy. A mean dose of 76 Gy was delivered to the prostate with intensity-modulated radiotherapy. Arm B: high-risk patients (T2b-T3, Gleason score >or=7, pretreatment PSA >or=10) were treated with combined radio-gene therapy and hormonal therapy. Hormonal therapy was comprised of a 4-month leuprolide injection and 2-week use of flutamide. Arm C: Stage D1 (positive pelvic lymph node) patients received the same regimen as Arm B, with the additional 45 Gy to the pelvic lymphatics. Treatment-related toxicity was assessed using Cancer Therapy Evaluation Program common toxicity score and Radiation Therapy Oncology Group (RTOG) toxicity score. RESULTS: Thirty patients (13 in Arm A, 14 in Arm B, and 3 in Arm C) completed the trial. Median follow-up was 5.5 months. Eleven patients (37%) developed flu-like symptoms (Cancer Therapy Evaluation Program Grade 1) of fatigue and chills/rigors after gene therapy injection but recovered within 24 h. Four patients (13%) and 2 patients (7%) developed Grade 1 and 2 fever, respectively. There was no patient with weight loss. One patient in Arm B developed Grade 3 elevation in liver enzyme, whereas 11 and 2 patients developed Grade 1 and 2 abnormal liver function tests. There was no Grade 2 or above hematologic toxicity. Three patients had transient rise in creatinine. There was no RTOG Grade 3 or above lower gastrointestinal toxicity. Toxicity levels were as follows: 4 patients (13%), Grade 2; 6 patients (20%), Grade 1; and 20 patients (67%), no toxicity. There was 1 patient with RTOG Grade 3 genitourinary toxicity, 12 patients (40%) with Grade 2, 8 patients (27%) with Grade 1, and 9 patients (30%) with no toxicity. No patient dropped out from the trial or had to withhold treatment because of severe toxicity. CONCLUSIONS: This is the first trial of its kind in the field of prostate cancer that aims to expand the therapeutic index of radiotherapy by combining in situ gene therapy. Initial experience has demonstrated the safety of this approach. There is no added toxicity to each therapy used alone. Long-term follow-up and larger cohort studies are warranted to evaluate long-term toxicity and efficacy.


Subject(s)
Genetic Therapy/methods , Prostatic Neoplasms/therapy , Adenoviridae , Adult , Aged , Aged, 80 and over , Combined Modality Therapy , Flutamide/therapeutic use , Genetic Vectors/therapeutic use , Humans , Leuprolide/therapeutic use , Lymphatic Irradiation , Male , Middle Aged , Prostatic Neoplasms/radiotherapy , Simplexvirus , Thymidine Kinase/genetics
19.
Breast J ; 7(4): 233-9, 2001.
Article in English | MEDLINE | ID: mdl-11678800

ABSTRACT

The purpose of this study was to determine if intensity modulated radiation therapy (IMRT) offers a better treatment plan compared to conventional radiotherapy for patients with pectus excavatum desiring breast-conserving therapy and to assess the feasibility of simultaneous modulated accelerated radiation therapy (SMART) boost. A patient with pectus excavatum desired breast-conserving therapy for her early stage breast cancer. She underwent lumpectomy and axillary lymph node dissection followed by chemotherapy. She was then referred for radiotherapy. A breast board (Med-Tec) with aquaplast body cast was used to limit the movement of the patient, chest wall, and breasts before planning a computed tomography (CT) scan. IMRT including dose-volume histogram (DVH) was compared to that of the conventional plan using parallel opposed tangential beams with a 15-degree wedge pair. Forty-five gray was prescribed to the whole breast to each plan, while 50 Gy was prescribed to the tumor bed using IMRT with SMART boost in 25 fractions over 5 weeks. The coverage of the whole breast was adequate for both plans. IMRT allowed a more homogeneous dose distribution within the breast at the desired dose range. With IMRT there is less volume of ipsilateral lung receiving the radiation dose that is above the tolerance threshold of 15 Gy when compared to that of the conventional plan. However, there is more volume of surrounding normal tissues (the heart, spinal cord, and contralateral breast and lung) receiving low-dose irradiation when IMRT was employed. SMART boost was feasible, allowing a mean dose of 57 Gy to be delivered to the tumor bed simultaneously along with the rest of the breast in 5 weeks. IMRT is feasible in treating early breast cancer patients with pectus excavatum by decreasing the ipsilateral lung volume receiving high-dose radiation when compared to the conventional method. SMART boost shortens the overall treatment time that may have potential radiobiological benefit.


Subject(s)
Breast Neoplasms/radiotherapy , Carcinoma, Ductal, Breast/radiotherapy , Funnel Chest/complications , Radiotherapy, Conformal/methods , Adult , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/surgery , Carcinoma, Ductal, Breast/diagnostic imaging , Carcinoma, Ductal, Breast/surgery , Dose-Response Relationship, Radiation , Female , Humans , Mastectomy, Segmental , Radiotherapy Planning, Computer-Assisted , Time Factors , Tomography, X-Ray Computed
20.
Br J Haematol ; 113(2): 470-8, 2001 May.
Article in English | MEDLINE | ID: mdl-11380418

ABSTRACT

Thrombopoietin (TPO), the primary regulator of megakaryocytopoiesis, plays important roles in early haematopoiesis. Previously, we have demonstrated that TPO induces a characteristic pattern of apoptosis during ex vivo expansion of cord blood (CB) CD34+ cells. In this study, we have demonstrated that the TPO-induced apoptotic cells belong to the megakaryocytic (MK) lineage and that initially expanding MK progenitors declined along with the appearance of TPO-induced apoptosis. Human CB CD34+ cells were expanded in serum-free conditions with TPO. Multidimensional flow cytometry using simultaneous measurement of apoptosis and immunophenotyping showed that the TPO-induced apoptotic cells appeared in CD61+ fractions. Immunocytochemical analysis of the fluorescent activated cell-sorted fractions showed that the apoptosis-associated CD44low fraction expressed CD61. Clonogenic assay revealed 7.4 +/- 0.50-fold increase of total megakaryocyte colony-forming units (CFU-MKs) during the initial 9 d. Thereafter, the number of CFU-MKs decreased in parallel with the increase of apoptosis. When the MK colonies were subdivided according to size, the proportion of large colonies progressively decreased, while that of medium and small colonies increased. In particular, from d 6 small colonies became predominant. These results suggested that the MK progenitors matured as they expanded during ex vivo expansion with TPO and then proceeded to apoptosis.


Subject(s)
Antigens, CD34 , Apoptosis , Fetal Blood/immunology , Megakaryocytes/cytology , Thrombopoietin/pharmacology , Antigens, CD , Cell Differentiation , Cell Division , Cells, Cultured , Colony-Forming Units Assay , Culture Media, Serum-Free , Flow Cytometry , Humans , Hyaluronan Receptors , Immunohistochemistry , Immunophenotyping , Integrin beta3 , Platelet Membrane Glycoproteins
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