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1.
Polymers (Basel) ; 15(22)2023 Nov 17.
Article in English | MEDLINE | ID: mdl-38006167

ABSTRACT

The use of mixed matrix membranes (MMMs) comprising metal-organic frameworks (MOFs) for the separation of CO2 from flue gas has gained recognition as an effective strategy for enhancing gas separation efficiency. When incorporating porous materials like MOFs into a polymeric matrix to create MMMs, the combined characteristics of each constituent typically manifest. Nevertheless, the inadequate dispersion of an inorganic MOF filler within an organic polymer matrix can compromise the compatibility between the filler and matrix. In this context, the aspiration is to develop an MMM that not only exhibits optimal interfacial compatibility between the polymer and filler but also delivers superior gas separation performance, specifically in the efficient extraction of CO2 from flue gas. In this study, we introduce a modification technique involving the grafting of poly(ethylene glycol) diglycidyl ether (PEGDE) onto a UiO-66-NH2 MOF filler (referred to as PEG-MOF), aimed at enhancing its compatibility with the 6FDA-durene matrix. Moreover, the inherent CO2-philic nature of PEGDE is anticipated to enhance the selectivity of CO2 over N2 and CH4. The resultant MMM, incorporating 10 wt% of PEG-MOF loading, exhibits a CO2 permeability of 1671.00 Barrer and a CO2/CH4 selectivity of 22.40. Notably, these values surpass the upper bound reported by Robeson in 2008.

2.
ACS Omega ; 7(15): 12956-12970, 2022 Apr 19.
Article in English | MEDLINE | ID: mdl-35474770

ABSTRACT

We prepared Nafion composite membranes by impregnating Nafion-212 with polydopamine, poly(sulfonated dopamine), and poly(dopamine-co-sulfonated dopamine) using the swelling-filling method to generate nanopores in the Nafion framework that were filled with these polymers. Compared to the pristine Nafion-212 membrane, these composite membranes showed improved thermal and mechanical stabilities due to the strong interactions between the catecholamine of the polydopamine derivatives and the Nafion matrix. For the composite membrane filled with poly(sulfonated dopamine) (N-PSDA), further interactions were induced between the Nafion and the sulfonic acid side chain, resulting in enhanced water uptake and ion conductivity. In addition, filling the nanopores in the Nafion matrix with polymer fillers containing aromatic hydrocarbon-based dopamine units led to an increase in the degree of crystallinity and resulted in a significant decrease in the hydrogen permeability of the composite membranes compared to Nafion-212. Hydrogen crossovers 26.8% lower than Nafion-212 at 95% relative humidity (RH) (fuel cell operating conditions) and 27.3% lower at 100% RH (water electrolysis operating conditions) were obtained. When applied to proton exchange membrane-based fuel cells, N-PSDA exhibited a peak power density of 966 mW cm-2, whereas N-PSDA showed a current density of 4785 mA cm-2, which is 12.4% higher than Nafion-212 at 2.0 V and 80 °C.

3.
Membranes (Basel) ; 11(9)2021 Aug 25.
Article in English | MEDLINE | ID: mdl-34564467

ABSTRACT

Thin-film composite mixed matrix membranes (CMMMs) were fabricated using interfacial polymerization to achieve high permeance and selectivity for CO2 separation. This study revealed the role of substrate properties on performance, which are not typically considered important. In order to enhance the affinity between the substrate and the coating solution during interfacial polymerization and increase the selectivity of CO2, a mixture of polyethylene glycol (PEG) and dopamine (DOPA) was subjected to a spinning process. Then, the surface of the substrate was subjected to interfacial polymerization using polyethyleneimine (PEI), trimesoyl chloride (TMC), and sodium dodecyl sulfate (SDS). The effect of adding SDS as a surfactant on the structure and gas permeation properties of the fabricated membranes was examined. Thin-film composite hollow fiber membranes containing modified graphene oxide (mGO) were fabricated, and their characteristics were analyzed. The membranes exhibited very promising separation performance, with CO2 permeance of 73 GPU and CO2/N2 selectivity of 60. From the design of a membrane substrate for separating CO2, the CMMMs hollow fiber membrane was optimized using the active layer and mGO nanoparticles through interfacial polymerization.

4.
Polymers (Basel) ; 12(8)2020 Jul 27.
Article in English | MEDLINE | ID: mdl-32727152

ABSTRACT

In this study, precursor molecules based on PEG/PPG and polydimethylsiloxane (PDMS), both widely used rubbery polymers, were copolymerized with bulky adamantane into copolymer membranes. Ring-opening metathesis polymerization (ROMP) was employed during the polymerization process to create a structure with both ends crosslinked. The precursor molecules and corresponding polymer membranes were characterized using various analytical methods. The polymer membranes were fabricated using different compositions of PDMS and adamantane, to determine how the network structure affected their gas separation performance. PEG/PPG, in which CO2 is highly soluble, was copolymerized with PDMS, which has high permeability, and adamantane, which controlled the crosslinking density with a rigid and bulky structure. It was confirmed that the resulting crosslinked polymer membranes exhibited high solubility and diffusivity for CO2. Further, their crosslinked structure using ROMP technique made it possible to form good films. The membranes fabricated in the present study exhibited excellent performance, i.e., CO2 permeability of up to 514.5 Barrer and CO2/N2 selectivity of 50.9.

5.
J Menopausal Med ; 23(2): 96-101, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28951857

ABSTRACT

OBJECTIVES: The relationship between renal function and bone mineral density (BMD) is controversial. We evaluated the relationship between markers of renal function and BMD in healthy Korean women. METHODS: A total of 1,093 women who visited the health promotion center at Pusan National University hospital were included in the cross-sectional study. We divided the study population into two groups by BMD: osteopenia-osteoporosis and normal in the lumbar and femur regions, respectively. We compared the relationship between renal function and BMD using a logistic regression model and used SAS 9.3 (SAS Institute, Inc., Cary, NC, USA) for all statistical analysis. RESULTS: Blood urea nitrogen (BUN), creatinine, and cystatin C (Cys-C) were correlated with BMD in both the normal and osteopenia-osteoporosis groups, and in logistic regression analysis, BUN and Cys-C were correlated with lumbar and femur BMD. However, after we adjusted for age, menopause, and body mass index, only creatinine showed a negative correlation with lumbar BMD, and estimated glomerular filtration rate (eGFR) was related positively with femur BMD. CONCLUSIONS: Serum creatinine could be a marker for lumbar BMD and eGFR for femur BMD in Korean women without overt nephropathy.

6.
J Menopausal Med ; 23(1): 74-76, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28523263

ABSTRACT

Autoamputated ovary with mature cystic teratoma (MCT) is a rarely reported gynecologic entity with an unknown prevalence. A 34-year-old woman referred to our clinic for presumed left ovarian tumor. Pelvic examination, ultrasonography and computed tomography scan revealed a 5-cm, cystic ovarian mass with calcification and fat component, and tumor markers were as follows, cancer antigen (CA) 125; 10.4 U/mL, CA19-9; 2 U/mL. Laparoscopy was performed. The mass was identified in the left adnexal region without any ligamentous or direct connection with the pelvic organs. The right ovary was normal. However, the left ovary and the tube could not be identified in its proper anatomical location. The mass was successfully removed with sharp and blunt dissection. A review of histopathologic study revealed a MCT. The patient became pregnant within seven months and gave birth to a healthy baby by cesarean section. We present a rare case of an autoamputated ovary with MCT.

7.
Obstet Gynecol Sci ; 60(1): 118-123, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28217683

ABSTRACT

Lymphoepithelioma-like carcinoma (LELC) of the uterine cervix is exceedingly uncommon. We herein report a rare case of cervical LELC. A 45-year-old woman was admitted to gynecology department with vaginal bleeding for one month. Liquid-based cytology revealed atypical endometrial cells, not otherwise specified on her cervix. On a hysteroscopy, an endocervical mass was identified and the pathologic result was consistent with poorly differentiated squamous cell carcinoma. Magnetic resonance imaging and positron emission tomography with 2-deoxy-2-[fluorine-18] fluoro-D-glucose integrated with computed tomography revealed a 3.1-cm endocervical mass without distant metastasis or enlarged lymph nodes. The International Federation of Gynecology and Obstetrics stage was IB1. A radical hysterectomy and bilateral pelvic lymph node dissection were performed. The pathologic diagnosis was a poorly differentiated carcinoma, showing features of LELC. She has been followed for 8 months without adjuvant treatment since the surgery, during which time there has been no evidence of tumor recurrence or metastasis.

8.
Taiwan J Obstet Gynecol ; 55(1): 35-9, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26927245

ABSTRACT

OBJECTIVE: The purpose of this study was to compare clinical outcomes of conventional laparoscopic surgery and laparoendoscopic single-site surgery (LESS) in the surgical treatment of tubal ectopic pregnancy. MATERIAL AND METHODS: A total of 156 patients were diagnosed with ectopic pregnancies by ultrasonography and serum ß-human chorionic gonadotrophin (ß-hCG) levels at Pusan National University Yangsan Hospital from January 2009 through December 2013. We excluded 28 patients who only received medical treatment, 15 patients who underwent surgery by laparotomy for severe hypovolemic shock, and 30 patients who presented with less than 1 L of hemoperitoneum. Of the 83 patients with massive hemoperitoneum, 38 patients had LESS performed while the remaining 45 patients underwent conventional laparoscopic surgery. RESULTS: In this study, there were no statistically significant differences in clinical outcomes in either surgical method except for operative time. Operative time of LESS was significantly shorter than conventional surgery for patients with more than 500 mL of hemoperitoneum. CONCLUSION: LESS is a safe and feasible surgical approach in the treatment of tubal ectopic pregnancy. At the same time, LESS has been shown to be more effective than conventional laparoscopic surgery in handling massive hemoperitoneum of more than 1 L, which is a common complication of ectopic pregnancy.


Subject(s)
Hemoperitoneum/complications , Laparoscopy/methods , Pregnancy, Tubal/surgery , Adult , Chorionic Gonadotropin, beta Subunit, Human/blood , Female , Humans , Operative Time , Pregnancy , Pregnancy, Tubal/blood , Pregnancy, Tubal/diagnostic imaging , Ultrasonography
9.
J Menopausal Med ; 22(3): 184-187, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28119900

ABSTRACT

We report a non-puerperal uterine inversion with nulliparous women caused by huge pedunculated submucosal fibroid. Massive bleeding from protruding mass through vagina brought the heart to stop in 42-year-old nulliparous woman. She became cardiopulmonary resuscitation survivor in emergency room and then underwent laparotomy which ended in successful myomectomy rather than hysterectomy considering her demand for future fertility. Meticulous and adequate fluid therapy and transfusion was also administered to recover from hypovolemic status. Pathologic report confirmed benign submucosal fibroid with degeneration, necrosis and abscess formation. Thus, clinician should be aware of uterine inversion when encountered with huge protruding vaginal mass and consider uterus-preserving management as surgical option when the future fertility is concerned.

10.
J Menopausal Med ; 20(1): 21-31, 2014 Apr.
Article in English | MEDLINE | ID: mdl-25371888

ABSTRACT

OBJECTIVES: To examine the effect of diazoxide on hypoxia-induced soluble fms-like tyrosin kinase-1 (sFlt-1) release in JEG-3 choriocarcinoma cells. METHODS: Cells were cultured under normoxia (20% O2) or hypoxia (1% O2), and expression of sFlt-1 mRNA and protein release was determined by quantitative real-time reverse-transcriptase polymerase chain reaction (qRT-PCR) assays and enzyme-linked immunosorbent assay (ELISA). RESULTS: Tumor necrosis factor-alpha (TNF-α) as well as hypoxia stimulated sFlt-1 release and diazoxide inhibited both of them. The selective inhibitor of mitochondrial adenosine triphosphat (ATP)-sensitive K(+) channel opener (KATP) 5-hydroxydecanoate (5-HD) completely reversed the diazoxide-induced inhibition of hypoxia-stimulated sFlt-1 release. qRT-PCR and Western blot analyses showed that diazoxide up-regulated the heme oxygenase-1 (HO-1) expression. In addition, the HO-1 inducer cobalt protoporphyrin (CoPP) and the metabolic product of HO-1 bilirubin mimicked diazoxide to inhibit sFlt-1 release and reactive oxygen species (ROS) production under hypoxia, whereas the HO-1 inhibitor zinc protoporphyrin IX (ZnPP IX) antagonized the effect of diazoxide. In cells transfected with the HO-1 siRNA, diazoxide did not exert any effect on sFlt-1 release and ROS production under hypoxia. CONCLUSION: These results, taken together, strongly suggest that up-regulation of the HO-1 expression is the crucial mechanism responsible for the diazoxide-induced inhibition of the sFlt-1 release and ROS production under hypoxia.

11.
J Menopausal Med ; 20(2): 57-68, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25371895

ABSTRACT

OBJECTIVES: We examined the effect of sildenafil citrate on advanced glycation end products (AGEs)-induced soluble fms-like tyrosine kinase 1 (sFlt-1) release in JEG-3 choriocarcinoma cells. METHODS: Cells were incubated with control bovine serum albumin (BSA) or AGEs-BSA, and expression of sFlt-1 mRNA and protein release was determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. AGEs-BSA increased sFlt-1 mRNA expression and protein release in a dose-dependent manner. RESULTS: Sildenafil citrate suppressed sFlt-1 mRNA expression and protein release in cells treated with AGEs-BSA in a dose-dependent manner. Likewise, it inhibited the increase of reactive oxygen species (ROS) production and NF-κB activity in these cells. Cobalt protoporphyrin (CoPP) and bilirubin also inhibited sFlt-1 release and ROS production in cells treated with AGEs-BSA, whereas zinc protoporphyrin IX (ZnPP IX) antagonized the effect of sildenafil citrate. In cells transfected with the heme oxygenase-1 (HO-1) siRNA, sildenafil citrate failed to inhibit the sFlt-1 release and ROS production. CONCLUSION: These results strongly suggest that sildenafil citrate inhibits sFlt-1 release and ROS production in cells treated with AGEs-BSA through upregulation of the HO-1 expression in JEG-3 cells.

12.
Oncol Res Treat ; 37(1-2): 30-4, 2014.
Article in English | MEDLINE | ID: mdl-24613906

ABSTRACT

PURPOSE: Positron emission tomography/computer tomography (PET/CT) utilizing [(18)F]fluorodeoxyglucose ((18)F-FDG) has been recommended for the diagnosis, staging, therapy monitoring, prediction of prognosis, and detection of recurrence in endometrial cancer. We aimed to define the correlations of biological markers with (18)F-FDG uptake in endometrial cancer. METHODS: 29 patients (55 ± 8.93 years) with endometrial cancer were included in this study. All patients underwent hysterectomy and bilateral salpingo-oophorectomy with or without para-aortic lymphadenectomy at the department of Obstetrics and Gynecology of Pusan National University Hospital. Immunohistochemical studies were performed for glucose transporter 1 (GLUT-1), hexokinase II (HK-II), hypoxia-inducible factor 1α (HIF-1α), vascular endothelial growth factor (VEGF) and carbonic anhydrase IX (CA-IX). RESULTS: There were positive correlations between FDG uptake and GLUT-1 (r = 0.375, p = 0.0452), and HK-II (r = 0.537, p = 0.0027). However, HIF-1α (r = 0.153, p = 0.4283), VEGF (r = -0,101, p = 0.6032) and CA-IX (r = 0.240, p = 0.2105) were not significantly associated with FDG uptake. No significant correlations were found among the expression levels of biological markers. CONCLUSION: FDG uptake in endometrial cancer was significantly associated with GLUT-1 and HK-II, while HIF-1α, VEGF and CA-IX were not associated with FDG uptake. No significant correlations were found among the expression levels of biological markers.


Subject(s)
Biomarkers, Tumor/metabolism , Endometrial Neoplasms/diagnostic imaging , Endometrial Neoplasms/metabolism , Fluorodeoxyglucose F18/pharmacokinetics , Neoplasm Proteins/metabolism , Positron-Emission Tomography/methods , Adult , Aged , Female , Humans , Middle Aged , Radiopharmaceuticals/pharmacokinetics , Reproducibility of Results , Sensitivity and Specificity , Statistics as Topic
13.
J Menopausal Med ; 19(3): 139-42, 2013 Dec.
Article in English | MEDLINE | ID: mdl-25371880

ABSTRACT

Primary vaginal cancer combined with uterine prolapse is very rare. We present a case of 80-year-old postmenopausal women complaints of something coming out per vagina for the past 20 years, along with blood stained discharge, foul odor leukorrhea, and severe pelvic pain for the last 3 months. A 4 × 5 cm ulcer was present on middle third of vaginal wall with marked edema and ulceration of surrounding tissue. The prolapse was reduced under intravenous sedation in operating room. On gynecologic examination, uterus was normal in size, no adnexal mass was examined, and both parametrium were thickened. Papanicolaou smear was normal. Biopsy of the ulcer at vaginal wall revealed invasive squamous cell carcinoma of vagina. Magnetic Resonance Imaging of abdomen and pelvis showed left hydronephrosis and liver metastasis. Positron emission tomography (PET)/computed tomography (CT) revealed metastasis to lung, liver and iliac bone. She died from progression of disease one month after diagnosis.

14.
J Menopausal Med ; 19(3): 147-50, 2013 Dec.
Article in English | MEDLINE | ID: mdl-25371882

ABSTRACT

Uterine leiomyoma is one of the most common gynecological tumor, whereas acute torsion of the uterine leiomyoma is very rare. We report a case of subserosal leiomyoma that was first detected by ultrasonography, and further confirmed as torsion of subserosal leiomyoma by laparoscopic surgery.

15.
J Menopausal Med ; 19(3): 154-7, 2013 Dec.
Article in English | MEDLINE | ID: mdl-25371884

ABSTRACT

Adenoid basal carcinoma of the uterine cervix is uncommon neoplasia mostly occurring in postmenopausal women. It has excellent prognosis and a favorable clinical course. In addition, adenoid basal carcinoma is differentiated from adenoid cystic carcinoma by histologic and cellular morphologies, and immunohistochemistry. In this paper, we present the case of a 22 year old Korean female. She initially had a high-grade squamous intraepithelial lesion (HSIL) on Pap smear and a subsequent cervical loop electrosurgical excision procedure (LEEP) specimen revealing adenoid basal carcinoma. The lesion showed the histologic characteristics of adenoid basal carcinoma. Because of the lesion's low potential for recurrence and metastasis, the young primipara had a conization procedure performed and has been under close observation.

16.
Heart Vessels ; 26(2): 196-205, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21188388

ABSTRACT

In this study, we evaluated the effect of culture-expanded mesenchymal stem cells (MSCs), derived from amniotic membranes, on neovascularization and blood flow, in an animal model of limb ischemia in immune-deficient mice. MSCs were cultured from human amniotic membranes by collagenase digestion. Human amniotic mesenchymal stem cells (hAMSCs) were administered intramuscularly at three different sites of the ischemic leg whose femoral vessels were ligated. After 4 weeks of culture, a population of homogeneous mesenchymal cells was isolated from the human amniotic membranes after confluence was reached. We performed three different groups of mice model [controls, hAMSCs, conditioned media from the hAMSCs (hAMSCs-CM)]. The blood flow recovery in the hindlimb ischemia model was significantly higher in the hAMSC-transplanted group than in the control group. Moreover, hAMSCs-CM significantly improved the cutaneous blood flow. The histological examination showed that red fluorescence (CM-DiI)-labeled hAMSCs was detected in the interstitial tissues between the muscle fibers 2 weeks after transplantation. The results of this study showed that hAMSCs may be an attractive, alternative source of progenitor or stem cells for basic research as well as clinical applications.


Subject(s)
Amnion/cytology , Fetal Stem Cells/transplantation , Ischemia/surgery , Mesenchymal Stem Cell Transplantation , Muscle, Skeletal/blood supply , Neovascularization, Physiologic , Angiogenic Proteins/metabolism , Animals , Cell Differentiation , Cell Proliferation , Cell Separation , Cell Tracking , Cells, Cultured , Culture Media, Conditioned/metabolism , Cytokines/metabolism , Disease Models, Animal , Fetal Stem Cells/metabolism , Hindlimb , Humans , Immunophenotyping , Injections, Intramuscular , Ischemia/metabolism , Ischemia/physiopathology , Mice , Mice, Inbred BALB C , Mice, Nude , Microscopy, Fluorescence , Recovery of Function , Regional Blood Flow , Time Factors
17.
Exp Mol Med ; 38(2): 119-25, 2006 Apr 30.
Article in English | MEDLINE | ID: mdl-16672765

ABSTRACT

Rett syndrome (RTT) is an X-linked dominant neurodevelopmental disorder affecting 1 per 10,000-15,000 female births worldwide. The disease-causing gene has been identified as MECP2 (methyl-CpG-binding protein 2). In this study, we performed diagnostic mutational analysis of the MECP2 gene in RTT patients. Four exons and a putative promoter of the MECP2 gene were analyzed from the peripheral blood of 43 Korean patients with Rett syndrome by PCR-RFLP and direct sequencing. Mutations were detected in the MECP2 gene in approximately 60.5% of patients (26 cases/43 cases). The mutations consisted of 14 different types, including 9 missense mutations, 4 nonsense mutations and 1 frameshift mutation. Of these, three mutations (G161E, T311M, p385fsX409) were newly identified and were determined to be disease-causing mutations by PCR- RFLP and direct sequencing analysis. Most of the mutations were located within MBD (42.3%) and TRD (50%). T158M, R270X, and R306C mutations were identified at a high frequency. Additionally, an intronic SNP (IVS3+23C>G) was newly identified in three of the patients. IVS3+23C>G may be a disease-related and Korea-specific SNP for RTT. L100V and A201V are apparently disease-causing mutations in Korean RTT, contrary to previous studies. Disease-causing mutations and polymorphisms are important tools for diagnosing RTT in Koreans. The experimental procedures used in this study should be considered for clinical molecular biologic diagnosis.


Subject(s)
Methyl-CpG-Binding Protein 2/genetics , Mutation , Rett Syndrome/genetics , Base Sequence , DNA Mutational Analysis , Female , Humans , Korea , Male , Molecular Sequence Data , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Polymorphism, Single Nucleotide , Rett Syndrome/diagnosis
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