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1.
Chemosphere ; 283: 131134, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34157619

ABSTRACT

Magnesium ferrites (MgFe2O4) are important class of ferrites that have been receiving greater attention as promising excellent photocatalyst due to its low cost, wide light spectrum response and environment-friendly nature. However, its poor electronic conductivity and fast charge carrier recombination hinders its electrocatalytical applications. Hence, accelerating charge carriers separation efficiency is important to modify the photoelectrochemical performance of MgFe2O4. Herein, novel Zn ions doped MgFe2O4 nanospheres are fabricated for the first time. Zn ions are doped into MgFe2O4 nanostructures from surface to enhance their charge separation efficiency. The doped MgFe2O4 nanostructures show significant photocatalytic activity and enhanced photocurrent density than that of pristine MgFe2O4.The improved photoelectrocatalytic performance is attributed to doping effect, were Zn ions actually enhance the conductivity. Zn ions enhance the activity of MgFe2O4 and accelerate the charge transfer properties in MgFe2O4. The results highlight that Zn doped MgFe2O4 nanospheres could be a potential candidate for photocatalytic and photoelectrochemical applications.


Subject(s)
Nanostructures , Water , Catalysis , Light , Zinc
2.
Environ Res ; 197: 111128, 2021 06.
Article in English | MEDLINE | ID: mdl-33861975

ABSTRACT

Neodymium (Nd) based perovskite (Nd1-xCoxFeO3) nanostructures were processed to address the rising energy and environment crisis through offering solutions by photocatalytic and photoelectrochemical (PEC) water splitting reactions. The impact of cobalt (Co) ions on the physicochemical properties of Nd-perovskites were studied using X-ray diffraction (XRD), Raman and electron microscopic instruments. The interaction of metal ions was studied in depth via X-ray photoelectron spectroscopy (XPS). Absorption and photoluminescence signals inferred the optical band gap to be lowered and defect states to increase upon Co substitution. Improved photocatalytic efficacy in Nd1-xCoxFeO3 was evaluated by comparative studies using NdFeO3. Secondly, the enhanced conductivities in Nd1-xCoxFeO3 studied via Nyquist plot was found to be advantageous in photoelectrode fabrication for PEC functions. Time-dependent photocurrent density results affirmed the stability in processed devices. Co ions were also inferred to boost the separation of charge carriers effectively. The improved performance in Nd1-xCoxFeO3 nanostructures were well justified to the successful incorporation of Co ions that sway the Nd-O, Co-O and Co-Fe-O bondings and boost the photon absorption and electronic conductivity to facilitate the observed performance.


Subject(s)
Nanostructures , Water , Calcium Compounds , Catalysis , Neodymium , Oxides , Titanium
4.
J Colloid Interface Sci ; 540: 476-485, 2019 Mar 22.
Article in English | MEDLINE | ID: mdl-30669105

ABSTRACT

Recently there has been immense interest in the exploration of richly available two-dimensional non-toxic layered material such as tin disulfide (SnS2) for potential employment in energy and environmental needs. In this regard, we report on the synthesis of few-layered Sn1-xMgxS2 nanosheets through a facile one-step hydrothermal route to address all such functions concerning photocatalysis and photoelectrochemical conversion. The crystalline order and structure of processed layered Sn1-xMgxS2 were initially found to exhibit a strong influence on their physicochemical properties. Their optical properties attest the Mg doping in SnS2 to benefit us with enhanced visible-light absorption via red-shift in their absorption edge. In the photoluminescence spectrum the emissions observed along visible and red region signifies the association of Mg related trap states in Sn1-xMgxS2. Next, the photocurrent and electrochemical impedance spectroscopic results revealed the Mg doping to promote the effective charge transfer process (which was beneficial to enhance their photocatalytic activity). Consequently, the layered Sn0.98Mg0.02S2 made photoanodes displayed 1.7 fold higher photocurrent density under simulated solar radiation with respect to their undoped counterpart. Furthermore, the layered Sn0.98Mg0.02S2 nanosheets exhibits enhanced visible light decomposition of organic dye while compared with pristine SnS2 nanosheets. The value of rate constants obtained for the Sn0.98Mg0.02S2 nanosheets was found to be 1.4 times higher than that of pristine SnS2. Finally, the results obtained through the present study projects the huge potential of layered Sn0.98Mg0.02S2 nanosheets for future multifunctional applications.

5.
Am J Transplant ; 18(2): 424-433, 2018 02.
Article in English | MEDLINE | ID: mdl-28758336

ABSTRACT

ABO-incompatible (ABOi) dual-graft (DG) adult living donor liver transplantation (ALDLT) is not commonly performed due to its inherently intricate surgical technique and immunological complexity. Therefore, data are lacking on the short- and long-term clinical outcomes of ABOi DG ALDLT. We performed a retrospective study by reviewing the medical records of patients who underwent ABOi DG ALDLT between 2008 and 2014. Additionally, computed tomography volumetric analysis was conducted to assess the graft regeneration rate. The mean age of a total of 28 recipients was 50.2 ± 8.5 years, and the mean model for end-stage liver disease score was 12.2 ± 4.6. The 1-, 3-, and 5-year patient survival rate was 96.4% during the mean follow-up period of 57.0 ± 22.4 months. The 1-, 3-, and 5-year graft survival rate was 96.4%, 94.2%, and 92.0%, respectively, and no significant differences were observed between ABO-compatible (ABOc) and ABOi grafts (P = .145). The biliary complication rate showed no significant difference (P = .195) between ABOc and ABOi grafts. Regeneration rates of ABOi grafts were not significantly different from those of ABOc grafts. DG ALDLT with ABOi and ABOc graft combination seems to be a feasible option for expanding the donor pool without additional donor risks.


Subject(s)
ABO Blood-Group System/adverse effects , Biliary Tract Diseases/mortality , Blood Group Incompatibility/complications , Graft Rejection/mortality , Liver Transplantation/adverse effects , Living Donors , Adult , Aged , Biliary Tract Diseases/etiology , Biliary Tract Diseases/pathology , Female , Follow-Up Studies , Graft Rejection/etiology , Graft Rejection/pathology , Graft Survival , Humans , Liver Function Tests , Male , Middle Aged , Postoperative Complications , Retrospective Studies , Risk Factors , Survival Rate , Treatment Outcome
6.
Am J Transplant ; 17(7): 1833-1842, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28097804

ABSTRACT

The large volume of adult living donor liver transplantations (ALDLTs) at our center affords a unique opportunity to examine the impact of acute-on-chronic liver failure (ACLF) among high-Model for End-Stage Liver Disease MELD score patients. From February 1998 to March 2010, 1958 cirrhotic recipients were analyzed to study the relationship between MELD scores and ALDLT outcomes. A total of 327 high-MELD score recipients were categorized into ACLF and non-ACLF groups, and their outcomes were compared. The 5-year graft and patient survival in the high-MELD group were 75.2% and 76.4%, respectively, which were significantly worse than the low and intermediate MELD groups. The presence of ACLF associated with higher MELD scores appeared to be the dominant factor responsible for the inferior results of patients with MELD score of 30-34 points. The 5-year graft survivals in the ACLF group was 70.5% and in the non-ACLF group it was 81.0% (p = 0.035). Therefore, ALDLT should be performed as soon as possible in high-MELD score patients prior to ACLF development. Moreover, ACLF patients should be separately categorized when analyzing the outcomes of ALDLT. ALDLT for ACLF patients should not be discouraged because favorable outcomes can be expected through timely ALDLT and comprehensive management.


Subject(s)
Acute-On-Chronic Liver Failure/surgery , End Stage Liver Disease , Liver Transplantation/methods , Living Donors , Severity of Illness Index , Acute-On-Chronic Liver Failure/physiopathology , Adolescent , Adult , Animals , Child , Female , Follow-Up Studies , Graft Rejection/etiology , Graft Survival , Humans , Liver Transplantation/adverse effects , Male , Middle Aged , Prognosis , Retrospective Studies , Risk Factors , Young Adult
7.
Transplant Proc ; 48(10): 3368-3372, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27931583

ABSTRACT

BACKGROUND: Acute graft-vs-host disease (GVHD) is a rare but life-threatening complication of orthotopic liver transplantation (OLT). We present 6 cases of GVHD after OLT. METHODS: Among our 4294 OLT recipients, we identified 6 patients (0.14%) who were diagnosed with GVHD. Their medical records were reviewed retrospectively. RESULTS: Liver graft types included deceased donor whole liver graft (n = 3) and right liver graft from son (n = 3). Mean recipient and donor ages were 57.2 ± 6.6 years and 32.7 ± 10.8 years, respectively. Onset of GVHD symptoms occurred 14 to 32 days after OLT, and initial symptoms were skin rash (n = 5) and fever (n = 1). GVHD was pathologically confirmed by skin or rectal biopsy. Chimerism of donor lymphocytes was identified in all 3 patients who underwent the short tandem repeat polymerase chain reaction assay. Attempts were made to treat the GVHD in all 6 patients by corticosteroids with or without low-dose calcineurin inhibitor, but we had to stop early or reduce these agents due to aggravation of pancytopenia and septic complications. Ultimately, 5 patients died 6 to 106 days after the onset of GVHD, and only 1 patient recovered. This surviving patient was diagnosed earlier and had been administered the recommended dosage of corticosteroid for a longer period with aggressive infection prophylaxis compared to the other cases. CONCLUSIONS: Because of very poor outcomes of GVHD after OLT, early diagnosis and vigorous treatment should be emphasized, although no effective treatment modality has been established yet. We strongly suggest performing aggressive infection prophylaxis during GVHD treatment.


Subject(s)
Adrenal Cortex Hormones/administration & dosage , Graft vs Host Disease/genetics , Liver Transplantation/adverse effects , Aged , Chimerism , Fatal Outcome , Graft vs Host Disease/drug therapy , Humans , Male , Microsatellite Repeats , Middle Aged , Polymerase Chain Reaction , Republic of Korea , Retrospective Studies , Time-to-Treatment , Tissue Donors , Treatment Outcome
8.
J Nanosci Nanotechnol ; 16(2): 1592-5, 2016 Feb.
Article in English | MEDLINE | ID: mdl-27433627

ABSTRACT

The thermal conductivity of a single ZnO nanowire with diameter of ~150 nm was measured using a four-point-probe 3omega method over a temperature range of 140-300 K. The measured ther- mal conductivity of ZnO nanowire is strongly reduced compared to bulk ZnO crystal due to the enhanced phonon-boundary and impurity (isotope) scattering. The maximum of the thermal conductivity is shifted to a higher temperature than that of bulk counterpart. Temperature dependent measurements show that beyond the low-temperature maximum, the thermal conductivity decreases with temperature as T(-1.5) indicating strong impurity (isotope) scattering at intermediate and high temperatures.

10.
Br J Radiol ; 82(979): e133-6, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19541940

ABSTRACT

We report multidetector row CT images of multiple gastrointestinal tumours in a patient with Type 1 neurofibromatosis who presented with haemoperitoneum. The use of CT demonstrated multiple, variably sized, ovoid, relatively well-enhancing masses in the intramural or subserosal location of the jejunum. The largest mass that showed a haemorrhagic necrosis caused haemoperitoneum. These imaging features are unique and differ from previous imaging features that have been reported in the radiological literature.


Subject(s)
Gastrointestinal Stromal Tumors/diagnostic imaging , Hemoperitoneum/etiology , Jejunal Neoplasms/diagnostic imaging , Neoplasms, Multiple Primary/diagnostic imaging , Neurofibromatosis 1/diagnostic imaging , Tomography, X-Ray Computed/methods , Gastrointestinal Stromal Tumors/complications , Hemoperitoneum/diagnostic imaging , Humans , Jejunal Neoplasms/complications , Male , Middle Aged , Neoplasms, Multiple Primary/complications , Neurofibromatosis 1/complications
11.
Acta Cytol ; 45(3): 459-64, 2001.
Article in English | MEDLINE | ID: mdl-11393086

ABSTRACT

BACKGROUND: Primary pulmonary paragangliomas are rare tumors. To our knowledge, there is no prior report on fine needle aspiration cytology (FNAC) in pulmonary paraganglioma. CASE: A 34-year-old man presented with an incidentally found solitary pulmonary mass. FNAC showed papillarylike clusters of epithelioid cells with round to oval nuclei, evenly dispersed chromatin, micronucleoli and occasional anisonucleosis. These cytologic features were suggestive of a sclerosing hemangioma or bronchioloalveolar carcinoma. A right lower lobectomy revealed a primary pulmonary paraganglioma. CONCLUSION: The possibility of pulmonary paraganglioma should be considered in the differential diagnosis of FNAC showing pseudopapillary clusters of epithelioid cells.


Subject(s)
Biopsy, Needle , Lung Neoplasms/pathology , Paraganglioma/pathology , Adenocarcinoma, Bronchiolo-Alveolar/pathology , Adult , Diagnosis, Differential , Hemangioma/pathology , Humans , Lung Neoplasms/diagnostic imaging , Male , Paraganglioma/diagnostic imaging , Radiography
12.
J Korean Med Sci ; 16(2): 250-2, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11306758

ABSTRACT

We report a case of lipoleiomyoma which arose in retroperitoneum and presented with progressively distended abdomen in a 56-yr-old woman. The tumor was well encapsulated and consisted of two components, benign smooth muscle cells and mature adipose tissue without any atypia. It is likely to be mistaken as extrarenal angiomyolipoma, well-differentiated liposarcoma and leiomyoma with fatty change. We review the histologic characteristics of previously reported myolipoma and describe essential points of differential diagnosis.


Subject(s)
Angiomyolipoma/pathology , Leiomyoma/pathology , Retroperitoneal Neoplasms/pathology , Diagnosis, Differential , Female , Humans , Liposarcoma/pathology , Middle Aged
13.
Korean J Intern Med ; 15(1): 85-8, 2000 Jan.
Article in English | MEDLINE | ID: mdl-10714098

ABSTRACT

A case of dermatomyositis presented as bronchiolitis obliterans organizing pneumonia has been rarely reported. We describe a 46-year-old female patient with dermatomyositis without elevation of creatine kinase presented as bronchiolitis obliterans organizing pneumonia. She was treated with prednisolone and azathioprine. Over a 2-year follow-up she has had no elevation of creatine kinase. The patient remains asymptomatic and has no medication for dermatomyositis and bronchiolitis obliterans organizing pneumonia two years after initial treatment. It has been suggested that the prognosis of dermatomyositis without creatine kinase elevation may be poor. Because the prognosis of bronchiolitis obliterans organizing pneumonia is generally believed to be good, we tentatively suggest that the normal value of creatine kinase in dermatomyositis does not always seem to herald a poor prognosis, an associated malignancy or severe interstitial lung disease.


Subject(s)
Creatine Kinase/blood , Cryptogenic Organizing Pneumonia/diagnosis , Dermatomyositis/diagnosis , Azathioprine/administration & dosage , Biopsy, Needle , Cryptogenic Organizing Pneumonia/pathology , Dermatomyositis/drug therapy , Dermatomyositis/enzymology , Dermatomyositis/pathology , Diagnosis, Differential , Female , Follow-Up Studies , Humans , Middle Aged , Prednisone/administration & dosage , Tomography, X-Ray Computed
14.
J Digit Imaging ; 12(4): 173-84, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10587912

ABSTRACT

In this article the authors propose a novel interslice coding algorithm especially appropriate for medical 3-dimensional (3D) images. The proposed algorithm is based on a video coding algorithm using motion estimation/compensation and transform coding. In the algorithm, warping is adopted for motion compensation. Then, by using adaptive mode selection, an MC residual image and original image are mixed up in the wavelet transform domain for improvement in coding performance. The mixed image is then compressed by the zerotree coding method. It is proven that the adaptive mode selection technique in the wavelet transform domain is very useful for medical 3D image coding. Simulation results show that the proposed scheme provides good performance, regardless of interslice distance, and is prospective for medical 3D image compression.


Subject(s)
Image Processing, Computer-Assisted , Radiographic Image Enhancement , Algorithms , Humans , Magnetic Resonance Imaging , Tomography, X-Ray Computed
15.
Scand J Gastroenterol ; 33(9): 923-7, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9759946

ABSTRACT

BACKGROUND: Helicobacter pylori strains possessing the cagA gene have been postulated to have a disease-specific relationship to peptic ulcer. The purpose of this study was to investigate the relationship between the infection with Helicobacter pylori expressing the cagA gene and the development of peptic ulcer diseases in Korean patients. METHODS: Genomic DNA and bacterial mRNA in the gastric mucosa were amplified by polymerase chain reaction (PCR) and reverse transcription PCR, using synthetic oligonucleotide primers to cagA genes to compare the prevalence of cagA genes in 35 patients with non-ulcer gastritis and 99 patients with gastric or duodenal ulcer disease (53 and 46, respectively). Two different primer sets for the cagA gene were used. The first primer set amplified a 298-bp region (nucleotides 1751-2048), and the second set amplified a 349-bp region (nucleotides 1228-1249). RESULTS: The expected 298 and 349-bp PCR amplicons were identified as follows: 1) 32 (91.4%) and 30 (85.7%) of 35 non-ulcer gastritis patients; 2) 5 1 (96.2%) and 50 (94.3%) of 53 benign gastric ulcer patients; and 3) 46 (100.0%) and 40 (87.0%) of 46 duodenal ulcer patients, respectively. CONCLUSION: These results strongly suggest that the cagA gene will not prove to be a useful marker to distinguish disease-specific H. pylori strains in the development of peptic ulcer diseases in Korean patients.


Subject(s)
Antigens, Bacterial/genetics , Bacterial Proteins/genetics , Helicobacter pylori/pathogenicity , Peptic Ulcer/microbiology , Bacterial Proteins/analysis , Biomarkers/analysis , DNA, Bacterial/analysis , Duodenal Ulcer/microbiology , Genome, Bacterial , Helicobacter Infections/complications , Helicobacter pylori/genetics , Humans , Korea/epidemiology , Polymerase Chain Reaction , Stomach Ulcer/microbiology
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