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1.
Int J Surg ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38573082

RESUMO

BACKGROUND: The aim of this study is to investigate the perioperative composite textbook outcomes of pancreatic surgery after minimally invasive pancreatoduodenectomy (MIPD). MATERIALS AND METHODS: The cohort study was conducted across 10 institutions and included 1552 patients who underwent MIPD registered with the Korean Study Group on Minimally Invasive Pancreatic Surgery between May 2007 and April 2020. We analyzed perioperative textbook outcomes of pancreatic surgery after MIPD. Subgroup analyses were performed to assess outcomes based on the hospital volume of MIPD. RESULTS: Among all patients, 21.8% underwent robotic pancreatoduodenectomy. High-volume centers (performing >20 MIPD/year) performed 88.1% of the procedures. The incidence of clinically relevant postoperative pancreatic fistula was 11.5%. Severe complications (Clavien-Dindo grade ≥IIIa) occurred in 15.1% of the cases. The 90-day mortality rate was 0.8%. The mean hospital stay was 13.7 days. Textbook outcomes of pancreatic surgery success were achieved in 60.4% of patients, with higher rates observed in high-volume centers than in low-volume centers (62.2% vs. 44.7%, P<0.001). High-volume centers exhibited significantly lower conversion rates (5.4% vs. 12.5%, P=0.001), lower 90-day mortality (0.5% vs. 2.7%, P=0.001), and lower 90-day readmission rates (4.5% vs. 9.6%, P=0.006) than those low-volume centers. CONCLUSION: MIPD could be performed safely with permissible perioperative outcomes, including textbook outcomes of pancreatic surgery, particularly in experienced centers. The findings of this study provided valuable insights for guiding surgical treatment decisions in periampullary disease.

2.
Molecules ; 29(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38611891

RESUMO

In this study, two distinct photocatalysts, namely tin(IV)porphyrin-sensitized titanium dioxide nanotubes (SnP-TNTs) and titanium dioxide nanofibers (TNFs), were synthesized and characterized using various spectroscopic techniques. SnP-TNTs were formed through the hydrothermal reaction of NaOH with TiO2 (P-25) nanospheres in the presence of Sn(IV)porphyrin (SnP), resulting in a transformation into Sn(IV)porphyrin-imbedded nanotubes. In contrast, under similar reaction conditions but in the absence of SnP, TiO2 (P-25) nanospheres evolved into nanofibers (TNFs). Comparative analysis revealed that SnP-TNTs exhibited a remarkable enhancement in the visible light photodegradation of model pollutants compared to SnP, TiO2 (P-25), or TNFs. The superior photodegradation activity of SnP-TNTs was primarily attributed to synergistic effects between TiO2 (P-25) and SnP, leading to altered conformational frameworks, increased surface area, enhanced thermo-chemical stability, unique morphology, and outstanding visible light photodegradation of cationic methylene blue dye (MB dye). With a rapid removal rate of 95% within 100 min (rate constant = 0.0277 min-1), SnP-TNTs demonstrated excellent dye degradation capacity, high reusability, and low catalyst loading, positioning them as more efficient than conventional catalysts. This report introduces a novel direction for porphyrin-incorporated catalytic systems, holding significance for future applications in environmental remediation.

3.
Cancers (Basel) ; 16(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38672628

RESUMO

(1) Background: The aim of this study was to compare the survival benefit of radical antegrade modular pancreatosplenectomy (RAMPS) with conventional distal pancreatosplenectomy (cDPS) in left-sided pancreatic cancer. (2) Methods: A retrospective propensity score matching (PSM) analysis was conducted on 333 patients who underwent RAMPS or cDPS for left-sided pancreatic cancer at four tertiary cancer centers. The study assessed prognostic factors and compared survival and operative outcomes. (3) Results: After PSM, 99 patients were matched in each group. RAMPS resulted in a higher retrieved lymph node count than cDPS (15.0 vs. 10.0, p < 0.001). No significant differences were observed between the two groups in terms of R0 resection rate, blood loss, hospital stay, or morbidity. The 5-year overall survival rate was similar in both groups (cDPS vs. RAMPS, 44.4% vs. 45.2%, p = 0.853), and disease-free survival was also comparable. Multivariate analysis revealed that ASA score, preoperative CA19-9, histologic differentiation, R1 resection, adjuvant treatment, and lymphovascular invasion were significant prognostic factors for overall survival. Preoperative CA19-9, histologic differentiation, T-stage, adjuvant treatment, and lymphovascular invasion were independent significant prognostic factors for disease-free survival. (4) Conclusions: Although RAMPS resulted in a higher retrieved lymph node count, survival outcomes were not different between the two groups. RAMPS was a surgical option to achieve R0 resection rather than a standard procedure.

4.
Int J Mol Sci ; 25(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38673768

RESUMO

Access to clean drinking water is a basic requirement, and eliminating pollutants from wastewater is important for saving water ecosystems. The porous structure and surface characteristics of metal-organic frameworks (MOFs) can function as a perfect scaffold for removing toxic compounds from wastewater. Porphyrins are promising building blocks for constructing MOFs. Porphyrin-based metal-organic frameworks (P-MOFs) have been fabricated using porphyrin ligands, metal clusters, or ions. These materials can harvest light from a wide region of the solar spectrum, and their framework morphology and physicochemical properties can be controlled by changing their peripheral subunits or metal ions. These porous crystalline materials have generated interest because of their distinctive characteristics, including large permanent porosity, interesting surface morphology, broad conformational diversity, high photostability, and semiconducting nature. This article discusses the recent progress and usefulness of P-MOFs. The fabrication procedures of P-MOFs are discussed, followed by the adsorptive and photocatalytic removal of contaminants from wastewater. The relationships between the geometries of P-MOFs and their light-harvesting and charge-transfer mechanisms for the photocatalytic degradation of pollutants are highlighted. Finally, some future perspectives and obstacles in the photodegradation usage of P-MOFs are discussed, along with feasible research directions to standardize efficient photocatalysts for improved photodegradation for water treatment.


Assuntos
Luz , Estruturas Metalorgânicas , Porfirinas , Poluentes Químicos da Água , Purificação da Água , Estruturas Metalorgânicas/química , Porfirinas/química , Purificação da Água/métodos , Poluentes Químicos da Água/química , Catálise , Águas Residuárias/química , Fotólise
5.
Molecules ; 29(3)2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38338355

RESUMO

Self-organized, well-defined porphyrin-based nanostructures with controllable sizes and morphologies are in high demand for the photodegradation of hazardous contaminants under sunlight. From this perspective, this review summarizes the development progress in the fabrication of porphyrin-based nanostructures by changing their synthetic strategies and designs. Porphyrin-based nanostructures can be fabricated using several methods, including ionic self-assembly, metal-ligand coordination, reprecipitation, and surfactant-assisted methods. The synthetic utility of porphyrins permits the organization of porphyrin building blocks into nanostructures, which can remarkably improve their light-harvesting properties and photostability. The tunable functionalization and distinctive structures of porphyrin nanomaterials trigger the junction of the charge-transfer mechanism and facilitate the photodegradation of pollutant dyes. Finally, porphyrin nanomaterials or porphyrin/metal nanohybrids are explored to amplify their photocatalytic efficiency.

6.
Molecules ; 28(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37764257

RESUMO

Two hybrid composite photocatalysts, denoted as SnP/AA@ZnO and SnP@ZnO, were fabricated by a reaction of trans-dihydroxo[5,10,15,20-tetrakis(4-pyridyl)porphyrinato]tin(IV) (SnP) and ZnO with and without pretreatment of adipic acid (AA), respectively. In SnP@ZnO, SnP and ZnO are likely held together by a coordinative interaction between the pyridyl N atoms of SnP and the Zn atoms on the surface of ZnO. In the case of SnP/AA@ZnO, the SnP centers were robustly coupled with ZnO nanoparticles through the AA anchors. SnP/AA@ZnO exhibited largely enhanced photocatalytic activities for the degradation of anionic amaranth (AM) dye under a visible light irradiation, compared to SnP, ZnO, and SnP@ZnO. The degradation efficiency of AM by SnP/AA@ZnO was 95% within 60 min at a rate constant of 0.048 min-1. The remarkable photocatalytic oxidation performance of SnP/AA@ZnO was mainly attributed to the synergistic effect between SnP and ZnO. This study is valuable for the development of highly effective composite photocatalytic systems in advanced oxidation processes and is of importance for the treatment of wastewater containing dyes.

7.
RSC Adv ; 13(34): 24077-24085, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37577097

RESUMO

A robust porous organic polymer cross-linked by Sn(iv) porphyrin (SnPOP) was fabricated by reacting trans-dihydroxo-[5,15,10,20-tetrakis(phenyl)porphyrinato]tin(iv) (SnP) with fluorinated polyimide (FPI) via sol-gel formation, followed by supercritical CO2 drying. The structural and porous properties of SnPOP were characterized using FT-IR, UV-vis, and fluorescence spectroscopies, along with field-emission scanning electron microscopy and gas sorption experiments. The reaction between the SnP's oxophilic Sn(iv) center and FPI's carboxylic acid moiety resulted in a controllable cross-linked porous texture. This material features the desirable physical properties of porphyrin and exhibits mesoporous structures with a relatively high surface area. SnPOP is thermally stable at temperatures up to 600 °C and highly resistant to boiling water, strong acids, and bases, owing to its assembly via formation of covalent bonds instead of typically weaker hydrogen bonds. The modified chemical and morphological structures of SnPOP showed an impressive CO2 uptake capacity of 58.48 mg g-1 at 273 K, with a preference for CO2 over N2. SnPOP showed significant efficiency in removing pollutant dyes, such as methylene blue and methyl orange, from dye-contaminated water. Additionally, SnPOP was a photocatalyst for fabricating silver nanoparticles of regular shape and size. All these properties make SnPOP a potential candidate for environmental applications like pollutant removal, gas storage, and separation.

8.
Cancers (Basel) ; 15(15)2023 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-37568666

RESUMO

BACKGROUND: As systemic treatment for pancreatic cancer advances, distal pancreatectomy with celiac axis resection (DP-CAR) has been considered a curative-intent surgical option for advanced pancreatic cancer. This study aimed to review the surgical and oncologic outcomes of patients undergoing DP-CAR based on Korean nationwide data. METHODS: We collected the data of patients who underwent DP-CAR for pancreatic cancer between 2007 and 2021 at seven major hospitals in Korea. The clinicopathological characteristics, postoperative complications, and data on the survival of the patients were retrospectively reviewed. Logistic regression analysis was performed to identify risk factors for postoperative complications and survival. RESULTS: A total of 75 patients, consisting mainly of borderline resectable (n = 32) or locally advanced (n = 30) pancreatic cancer, were included in the analysis. Forty-two (56.0%) patients underwent neoadjuvant treatment (NAT). Twenty (26.7%) patients experienced Clavien-Dindo grade ≥ 3 complications, including four patients with ischemic gastropathy, two with hepatic ischemia, and two procedure-related mortalities. Neoadjuvant chemotherapy increased the risk of postoperative complications (p = 0.028). The median recurrence-free and overall survival were 7 and 19 months, with a 5-year survival rate of 13% and 24%, respectively. In the NAT group, a decrease in CA 19-9 and the post-NAT maximum standardized uptake value (SUVmax) in positron emission tomography were associated with survival after surgical resection. CONCLUSIONS: Despite the possibility of major complications, DP-CAR could be a feasible option for achieving curative resection with fair survival outcomes in patients with borderline resectable or locally advanced pancreatic cancer. Further studies investigating the safety of the procedure and identifying proper surgical candidates with potential survival gains are necessary.

9.
Eye Contact Lens ; 49(11): 471-474, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37616173

RESUMO

PURPOSE: To describe a case of a patient treated for neurotrophic keratopathy (NK) with direct corneal neurotization (CN), where a modification to the CN technique allowed for semiscleral contact lens use postoperatively. OBSERVATION: Our patient had successful CN with improved corneal sensation. During the procedure, a 1.0 mm gutter was created between the limbus and nerve graft to allow for semiscleral contact lens fitting. CONCLUSIONS: With the use of preoperative planning and a limbal gutter during CN, a semiscleral contact lens can serve as a well-tolerated postoperative management option to improve visual acuity and protect the corneal surface in patients with NK.


Assuntos
Lentes de Contato , Doenças da Córnea , Distrofias Hereditárias da Córnea , Ceratite , Transferência de Nervo , Doenças do Nervo Trigêmeo , Humanos , Transferência de Nervo/métodos , Doenças da Córnea/cirurgia , Córnea/cirurgia , Córnea/inervação , Ceratite/cirurgia , Distrofias Hereditárias da Córnea/cirurgia , Doenças do Nervo Trigêmeo/cirurgia
10.
Korean J Clin Oncol ; 19(1): 32-37, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37449397

RESUMO

Pancreatic metastasis from papillary thyroid cancer (PTC) is extremely rare; only 18 cases have been reported in the literature. However, several reviews have highlighted similar characteristics between metastatic and primary pancreatic tumors. The patient was a 51-year-old male with a history of total thyroidectomy, modified radical neck dissection, and radioactive iodine ablation for PTC in 2014. Nodules suspected of metastasis were found in both lungs on chest computed tomography (CT). However, after 6 months, a follow-up chest CT showed no increase in size; thus, a follow-up observation was planned. Six years after his initial diagnosis, abdominal CT and pancreas magnetic resonance imaging revealed a 4.7 cm cystic mass with a 2.5 cm enhancing mural nodule in the pancreas tail. We diagnosed the pancreatic lesion as either metastatic cancer or primary pancreas cancer. The patient underwent distal pancreato-splenectomy. After surgery, the pathological report revealed that the mass was metastatic PTC. Pancreatic metastasis from PTC indicates an advanced tumor stage and poor prognosis. However, pancreatectomy can increase the survival rate when the lesion is completely resectable. Therefore, surgical resection should be considered as a treatment for pancreatic metastasis from PTC.

11.
Molecules ; 28(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36838873

RESUMO

Two hybrid composites (SnP@MCM-41 and SnP@SiO2) were fabricated by chemical adsorption of (trans-dihydroxo)(5,10,15,20-tetraphenylporphyrinato)tin(IV) (SnP) on mesoporous structured Mobil Composition of Matter No. 41 (MCM-41) and SiO2 nanoparticles. These materials were characterized by Fourier-transform infrared spectroscopy, ultraviolet-visible spectroscopy, fluorescence spectroscopy, transmission electron microscopy, and field-emission scanning electron microscopy techniques. The incorporation of SnP into MCM-41 and SiO2 supports efficient photocatalytic degradation of the anionic erioglaucine, cationic rhodamine B, and neutral m-cresol purple dyes under visible light irradiation in an aqueous solution. The performances of degradation of these dyes by these photocatalysts under visible light irradiation varied from 87 to 95%. The pseudo-first-order degradation rate constant of organic dyes for SnP@MCM-41 was higher than those of SnP@SiO2 and SnP. These visible light photocatalysts showed remarkable stability and reliable reusability.


Assuntos
Porfirinas , Dióxido de Silício , Dióxido de Silício/química , Difração de Raios X , Luz , Corantes/química , Catálise
12.
J Hepatobiliary Pancreat Sci ; 30(2): 252-262, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35766108

RESUMO

BACKGROUND: Previous studies have reported contrasting results regarding the advantages of spleen preservation during laparoscopic distal pancreatectomy (LDP) for preventing infectious complications. METHODS: A total of 3787 patients who underwent LDP for benign or low-grade malignant pancreatic disease in 92 centers across Korea and Japan were included in this retrospective study. Postoperative infectious complications and other complications were compared between LDP with splenectomy (LDPS) and LDP with spleen preservation (LSPDP) by propensity score matching (PSM) analysis. RESULTS: After PSM, the LSPDP group had a lower rate of overall infectious complications (P = .079) and a significantly lower rate of intra-abdominal abscess (P = .014) compared with the LDPS group. Within the LSPDP group, the vessel preservation subgroup had a significantly higher rate of infectious complications (P = .002) compared with the vessel resection subgroup. Low-volume centers had a higher rate of intra-abdominal abscess than high-volume centers in the LSPDP group (P = .001) and the splenic vessel preservation subgroup (P = .003). CONCLUSIONS: Spleen preservation in LDP for benign or borderline malignant pancreatic diseases was advantageous in lowering the risk of infectious complications, specifically intra-abdominal abscess. However, the risk of intra-abdominal abscess may differ according to the level of surgeon's experience.


Assuntos
Abscesso Abdominal , Laparoscopia , Pancreatopatias , Neoplasias Pancreáticas , Humanos , Baço/cirurgia , Esplenectomia/efeitos adversos , Esplenectomia/métodos , Pancreatectomia/efeitos adversos , Pancreatectomia/métodos , Estudos Retrospectivos , Pontuação de Propensão , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/complicações , Pancreatopatias/cirurgia , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Complicações Pós-Operatórias/cirurgia , Abscesso Abdominal/prevenção & controle , Abscesso Abdominal/complicações , Resultado do Tratamento
13.
Ophthalmic Plast Reconstr Surg ; 39(2): 150-155, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36095848

RESUMO

PURPOSE: In response to the coronavirus (COVID-19) pandemic, teprotumumab production was temporarily halted with resources diverted toward vaccine production. Many patients who initiated treatment with teprotumumab for thyroid eye disease were forced to deviate from the standard protocol. This study investigates the response of teprotumumab when patients receive fewer than the standard 8-dose regimen. METHODS: This observational cross-sectional cohort study included patients from 15 institutions with active or minimal to no clinical activity thyroid eye disease treated with the standard teprotumumab infusion protocol. Patients were included if they had completed at least 1 teprotumumab infusion and had not yet completed all 8 planned infusions. Data were collected before teprotumumab initiation, within 3 weeks of last dose before interruption, and at the visit before teprotumumab reinitiation. The primary outcome measure was reduction in proptosis more than 2 mm. Secondary outcome measures included change in clinical activity score (CAS), extraocular motility restriction, margin reflex distance-1 (MRD1), and reported adverse events. RESULTS: The study included 74 patients. Mean age was 57.8 years, and 77% were female. There were 62 active and 12 minimal to no clinical activity patients. Patients completed an average of 4.2 teprotumumab infusions before interruption. A significant mean reduction in proptosis (-2.9 mm in active and -2.8 mm in minimal to no clinical activity patients, P < 0.01) was noted and maintained during interruption. For active patients, a 3.4-point reduction in CAS ( P < 0.01) and reduction in ocular motility restriction ( P < 0.01) were maintained during interruption. CONCLUSIONS: Patients partially treated with teprotumumab achieve significant reduction in proptosis, CAS, and extraocular muscle restriction and maintain these improvements through the period of interruption.


Assuntos
COVID-19 , Exoftalmia , Oftalmopatia de Graves , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Oftalmopatia de Graves/tratamento farmacológico , Estudos Transversais
14.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430177

RESUMO

Two robust Sn(IV)-porphyrin-based supramolecular arrays (1 and 2) were synthesized via the reaction of trans-Pd(PhCN)2Cl2 with two precursor building blocks (SnP1 and SnP2). The structural patterns in these architectures vary from 2D to 3D depending on the axial ligation of Sn(IV)-porphyrin units. A discrete 2D tetrameric supramolecule (1) was constructed by coordination of {(trans-dihydroxo)[5,10-bis(4-pyridyl)-15,20-bis(phenyl) porphyrinato]}tin(IV) (SnP1) with trans-PdCl2 units. In contrast, the coordination between the {(trans-diisonicotinato)[5,10-bis(4-pyridyl)-15,20-bis(phenyl)porphyrinato]}tin(IV) (SnP2) and trans-PdCl2 units formed a divergent 3D array (2). Axial ligation of the Sn(IV)-porphyrin building blocks not only alters the supramolecular arrays but also significantly modifies the nanostructures, including porosity, surface area, stability, and morphology. These structural changes consequently affected the photocatalytic degradation efficiency under visible-light irradiation towards acid orange 7 (AO) dye in an aqueous solution. The degradation efficiency of the AO dye in the aqueous solution was observed to be between 86% to 91% within 90 min by these photocatalysts.


Assuntos
Nanoestruturas , Porfirinas , Estanho , Benzenossulfonatos , Porfirinas/química , Estanho/química
15.
World J Gastroenterol ; 28(36): 5351-5363, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36185633

RESUMO

BACKGROUND: Surgical resection is one of the most widely used modalities for the treatment of hepatocellular carcinoma (HCC). Early extrahepatic recurrence (EHR) of HCC after surgical resection is considered to be closely associated with poor prognosis. However, data regarding risk factors and survival outcomes of early EHR after surgical resection remain scarce. AIM: To investigate the clinical features and risk factors of early EHR and elucidate its association with survival outcomes. METHODS: From January 2004 to December 2019, we enrolled treatment-naïve patients who were ≥ 18 years and underwent surgical resection for HCC in two tertiary academic centers. After excluding patients with tumor types other than HCC and/or ineligible data, this retrospective study finally included 779 patients. Surgical resection of HCC was performed according to the physicians' decisions and the EHR was diagnosed based on contrast-enhanced computed tomography or magnetic resonance imaging, and pathologic confirmation was performed in selected patients. Multivariate Cox regression analysis was performed to identify the variables associated with EHR. RESULTS: Early EHR within 2 years after surgery was diagnosed in 9.5% of patients during a median follow-up period of 4.4 years. The recurrence-free survival period was 5.2 mo, and the median time to EHR was 8.8 mo in patients with early EHR. In 52.7% of patients with early EHR, EHR occurred as the first recurrence of HCC after surgical resection. On multivariate analysis, serum albumin < 4.0 g/dL, serum alkaline phosphatase > 100 U/L, surgical margin involvement, venous and/or lymphatic involvement, satellite nodules, tumor necrosis detected by pathology, tumor size ≥ 7 cm, and macrovascular invasion were determined as risk factors associated with early EHR. After sub-categorizing the patients according to the number of risk factors, the rates of both EHR and survival showed a significant correlation with the risk of early EHR. Furthermore, multivariate analysis revealed that early EHR was associated with substantially worse survival outcomes (Hazard ratio, 6.77; 95% confidence interval, 4.81-9.52; P < 0.001). CONCLUSION: Early EHR significantly deteriorates the survival of patients with HCC, and our identified risk factors may predict the clinical outcomes and aid in postoperative strategies for improving survival.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Fosfatase Alcalina , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Hepatectomia/efeitos adversos , Fator de Crescimento de Hepatócito , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/patologia , Prognóstico , Fator Regulador X1 , Estudos Retrospectivos , Albumina Sérica
16.
Membranes (Basel) ; 12(9)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36135854

RESUMO

In this work, low-cost ceramic membranes (CMs) were prepared from ultrafine starting powders such as kaolin, clay, and starch by a dry compaction method. The ceramic membranes were sintered at different temperatures and times and were characterized by XRD, XRF, TG-DTA, SEM-EDS, N2-BET, water absorption, compressive strength, and pure water flux. The optimal membrane, sintered at 1000 °C for 3 h, possessed water absorption of 27.27%, a compressive strength of 31.05 MPa, and pure water flux of 20.74 L/h m2. Furthermore, chitosan crosslinked with glutaraldehyde was coated on the surface of the ceramic membrane by the dip coating method, and the pore size of the chitosan-coated ceramic membrane (CCCM) was 16.24 nm. Eventually, the separation performance of this membrane was assessed for the removal of chromium(VI) from aqueous solution. The ultrafine filtration of Cr(VI) was studied in the pH range of 2-7. The maximum removal of Cr(VI) was observed to be 71.25% with a pH of 3. The prepared CCCM showed good membrane properties such as mechanical stability and ultrafine structure, which have important applications for the treatment of wastewater including such heavy metals.

17.
Molecules ; 27(12)2022 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-35744893

RESUMO

Efficient utilization of visible light for photocatalytic hydrogen production is one of the most important issues to address. This report describes a facile approach to immobilize visible-light sensitizers on TiO2 surfaces. To effectively utilize the sensitization of Sn(IV) porphyrin species for photocatalytic hydrogen production, perfluorosulfonate polymer (Nafion) matrix coated-TiO2 was fabricated. Nafion coated-TiO2 readily adsorbed trans-diaqua[meso-tetrakis(4-pyridinium)porphyrinato]tin(IV) cation [(TPyHP)Sn(OH2)2]6+ via an ion-exchange process. The uptake of [(TPyHP)Sn(OH2)2]6+ in an aqueous solution completed within 30 min, as determined by UV-vis spectroscopy. The existence of Sn(IV) porphyrin species embedded in the Nafion matrix coated on TiO2 was confirmed by zeta potential measurements, UV-vis absorption spectroscopy, TEM combined with energy dispersive X-ray spectroscopy, and thermogravimetric analysis. Sn(IV)-porphyrin cationic species embedded in the Nafion matrix were successfully used as visible-light sensitizer for photochemical hydrogen generation. This photocatalytic system performed 45% better than the uncoated TiO2 system. In addition, the performance at pH 7 was superior to that at pH 3 or 9. This work revealed that Nafion matrix coated-TiO2 can efficiently produce hydrogen with a consistent performance by utilizing a freshly supplied cationic Sn(IV)-porphyrin sensitizer in a neutral solution.


Assuntos
Porfirinas , Catálise , Polímeros de Fluorcarboneto , Hidrogênio/química , Porfirinas/química , Titânio
18.
World J Clin Cases ; 10(6): 2007-2014, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-35317136

RESUMO

BACKGROUND: Dedifferentiated liposarcoma (DDLPS) is an extremely rare neoplasm that exhibits various morphologies. The tumor is characterized by immunoreactivity to MDM2 and CDK4 and can be confirmed by detecting MDM2 amplification via fluorescence in situ hybridization (FISH). Herein, we report an unusual case of DDLPS arising from the duodenum. CASE SUMMARY: A 64-year-old man presented with repeated abdominal pain and weight loss. Radiologic studies revealed a mass of the duodenum involving the pancreas. The patient was treated with pylorus-preserving pancreaticoduodenectomy. Histologically, the tumor showed a high-grade sarcoma. Immunohistochemistry demonstrated that the tumor cells were positive for MDM2 and CDK4 expression. MDM2 amplification was detected via FISH, leading to the final diagnosis of DDLPS. Following surgery, the patient was treated in the intensive care unit due to peritonitis, and died 60 d after surgery. CONCLUSION: To the best of the authors' knowledge, this is the first case of primary duodenal DDLPS in Korea and the third case in the English-language literature. Care must be taken not to misdiagnose DDLPS as another high-grade tumor. Liposarcoma should be in the differential diagnosis list.

19.
ACS Omega ; 7(11): 9775-9784, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35350320

RESUMO

Three isomeric Zn(II)-Sn(IV)-Zn(II) porphyrin-based triads (T2, T3, and T4) were synthesized by the reaction of common Zn(II) porphyrins (ZnL) with different Sn(IV) porphyrins (SnP n ). The Sn(IV) porphyrin precursors differ with respect to the position of the pyridyl-N atoms. All compounds were characterized by 1H NMR, UV-vis, fluorescence spectroscopy, electrospray ionization-mass spectrometry, and field-emission scanning electron microscopy measurements. In these structures, the intramolecular cooperative metal-ligand coordination of the 3-pyridyl nitrogen in SnP 3 with axial ZnL and the π-π interactions between the adjacent porphyrin triad are the determining factors affecting the nanostructures of T3. Owing to the geometrical constraints of the SnP 2 center, this type of interaction is not possible for T2. Therefore, only the π-π interactions affect the self-assembly process. In the case of SnP 4 , intermolecular coordinative interactions and then π-π interactions are responsible for the nanostructure of T4. The morphology-dependent photocatalytic degradation of methyl orange (MO) dye in aqueous solution under visible light irradiation was observed for these photocatalysts, and the degradation ratio of MO varied from 76 to 94% within 100 min. Nanorod-shaped T3 exhibited higher performance compared to nanosphere T2 and nanoflake T4.

20.
Ann Hepatobiliary Pancreat Surg ; 26(2): 168-177, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35168203

RESUMO

Backgrounds/Aims: The goal of the present study was to evaluate the prognostic value of lymph node ratio (LNR) in distal cholangiocarcinoma (DCC) after curative intended surgery. Methods: Clinicopathological data of 162 DCC patients who underwent radical intended surgery between 2012 and 2020 were analyzed retrospectively. Prognostic factors related to overall survival (OS) and disease-free survival (DFS) were evaluated. Results: Median OS time and DFS time were 41 and 29 months, and 5-year OS rate and DFS rate were 44.7% and 38.1%, respectively. In the univariate analysis, significant prognostic factors for OS were histologic differentiation, American Joint Committee on Cancer (AJCC) stage, positive lymph node count, LNR, R1 resection, and perineural invasion. Preoperative carcinoembryonic antigen, carbohydrate antigen 19-9, infiltrative type, histologic differentiation, AJCC stage, positive lymph node count, LNR, R1 resection, perineural invasion, and lymph-vascular invasion were significant prognostic factors for DFS in the univariate analysis. In the multivariate analysis, histologic differentiation, R1 resection, and LNR were the independent prognostic factors for both OS and DFS. The LNR ≥ 0.2 group had a significantly poor prognosis in terms of OS (hazard ratio, 3.915; p = 0.002) and DFS (hazard ratio, 5.840; p < 0.001). Conclusions: LNR has significant value as a prognostic factor of DCC related to OS and DFS. LNR has the potential to be used as a modified staging system with furthermore studies.

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