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1.
Inorg Chem ; 63(9): 4185-4195, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38364251

RESUMO

Posttreatment of pristine metal-organic frameworks (MOFs) with suitable vapor may be an effective way to regulate their structures and properties but has been less explored. Herein, we report an interesting example in which a crystalline nonporous Eu(III)-MOF was transferred to a porous amorphous MOF (aMOF) via iodine vapor adsorption-desorption posttreatment, and the resulting aMOF showed improved turn-on sensing properties with respect to Ag+ ions. The crystalline Eu-MOF, namely, Eu-IPDA, was assembled from Eu(III) and 4,4'-{4-[4-(1H-imidazol-1-yl)phenyl]pyridine-2,6-diyl}dibenzoic acid (H2IPDA) and exhibited a two-dimensional (2D) coordination network based on one-dimensional secondary building blocks. The close packing of the 2D networks gives rise to a three-dimensional supramolecular framework without any significant pores. Interestingly, the nonporous Eu-IPDA could absorb iodine molecules when Eu-IPDA crystals were placed in iodine vapor at 85 °C, and the adsorption capacity was 1.90 g/g, which is comparable to those of many MOFs with large BET surfaces. The adsorption of iodine is attributed to the strong interactions among the iodine molecule, the carboxy group, and the N-containing group and leads to the amorphization of the framework. After immersion of the iodine-loaded Eu-IPDA in EtOH, approximately 89.7% of the iodine was removed, resulting in a porous amorphous MOF, denoted as a-Eu-IPDA. In addition, the remaining iodine in the a-Eu-IPDA framework causes strong luminescent quenching in the fluorescence emission region of the Eu(III) center when compared with that in Eu-IPDA. The luminescence intensity of a-Eu-IPDA in water suspensions was significantly enhanced when Ag+ ions were added, with a detection limit of 4.76 × 10-6 M, which is 1000 times that of pristine Eu-IPDA. It also showed strong anti-interference ability over many common competitive metal ions and has the potential to sense Ag+ in natural water bodies and traditional Chinese medicine preparations. A mechanistic study showed that the interactions between Ag+ and the absorbed iodine, the carboxylate group, and the N atoms all contribute to the sensing performance of a-Eu-IPDA.

2.
Inorg Chem ; 61(43): 16981-16985, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36251482

RESUMO

Metal-organic framework (MOF) glass is a new type of glass material, but it usually lacks sufficient porosity. Thus, regulating the pore structure of MOF glass to improve its adsorption performance is very important. Herein, we found that the porosity of MOF glasses agZIF-62 and agZIF-76 can be regulated via an ammonia-immersion approach. After ammonia immersion, the resulting agZIF-62-NH3 and agZIF-76-NH3 could be maintained in their glass states or converted to their amorphous states, respectively. Their porosity changed according to the gas adsorption experiments. Notably, compared with agZIF-62 and agZIF-76, the iodine uptake capacities for agZIF-62-NH3 and agZIF-76NH3 increased by 12 and 21 times, respectively. This work shows that the subsequent treatment of MOF glass can regulate their adsorption performance.

3.
Inorg Chem ; 58(21): 14660-14666, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31609588

RESUMO

A pair of homochiral coordination polymers, [Cu(DPT)]n (1M and 1P, HDPT = 3,5-di-4-pyridinyl-2H-tetrazole), were assembled from achiral precursors. Crystal structure analysis showed that they are chiral three-dimensional (3D) coordination polymers based on a new double-stranded helical building block that is composed of two different 1D helices. Interestingly, rare symmetry-breaking crystallization was observed, in which the possibility of obtaining enantio-enriched bulk product with excessive M enantiomers (1-A) was obviously higher than that for P enantiomers (1-B) as demonstrated in multiple, repeated experiments with single-crystal diffraction and vibrational circular dichroism (VCD) spectra. Moreover, compound [Cu(DPT)]n shows good chemical stability in water, with pH values ranging from 3 to 13, as well as in many common organic solvents. Photophysical properties, including thermochromic properties and two-photon excited luminescence, were studied, and the potential for applications in temperature sensing was exhibited. In addition, the photocatalytic degradation of methylene blue in water indicated that compound [Cu(DPT)]n can be used as a photocatalyst.

4.
Inorg Chem ; 58(4): 2899-2909, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30721040

RESUMO

Cationic framework materials capable of removing anionic pollutants from wastewater are highly desirable but relatively rarely reported. Herein, a cationic MOF (SCNU-Z1-Cl) possessing tubular channels with diameter of 1.5 nm based on Ni(II) and a nitrogen-containing ligand has been synthesized and applied to capture hazardous anionic contaminants from water. The SCNU-Z1-Cl exhibits high BET surface area of 1636 m2/g, and shows high hydrolytically stability in pH range from 4 to 10. Owing to the large tubular channels and the uncoordinated anions in the framework, the aqueous-phase anion-exchange applications of SCNU-Z1-Cl were explored with environmentally toxic oxo-anions including CrO42-, Cr2O72-, MnO4-, and ReO4-, and organic dyes. The adsorption of oxoanions exhibits high uptake kinetics and the adsorption capacities of CrO42-, Cr2O72-, MnO4-, and ReO4- are 126, 241, 292, and 318 mg/g, respectively, which were some of the highest values in the field of MOF/COF. In additional, the selectively is high when other concurrent anions are exist. The anionic dyes with different sizes including methyl orange, acid orange A, congo red, as well as methyl blue can be adsorbed by SCNU-Z1-Cl in few minutes to about 1 h. The adsorption capacities for them are 285, 180, 585, and 262 mg/g, respectively. In contrast, the adsorption kinetics for catinionic dyes with different sizes is obviously lower and exhibit a size-selectively adsorption that only cationic dye with suitable size (rhodamine B) can be adsorbed by SCNU-Z1-Cl. Consequently, SCNU-Z1-Cl can sepearate organic dyes in three different modes: size-dependent, charge-dependent, and kinetics-dependent selective adsorption. The excellent adsorption and separation properties of SCNU-Z1-Cl is attribute to the cationic framework, large tubular channel, as well as the high positive Zeta potential.

5.
Inorg Chem ; 58(20): 13979-13987, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31583885

RESUMO

A metal-organic framework (MOF), named SCNU-Z2, based on a new heterotopic tripodal nitrogen-containing ligand, has been constructed. Due to the replacement of one imidazole group in the reported ligand with one tetrazole group, the charge of the framework is changed from cationic to anionic but retains the same framework structure. The framework consists of tubular channels with a diameter of 1.5 nm and exhibits satisfactory stability in water with a pH range of 3-11. The anionic nature of the framework allows the effective adsorption of the cationic dyes MLB, CV, and RhB with capacities of 455.6, 847.4, and 751.8 mg/g, respectively. Among them, the adsorption capacities for SCNU-Z2 on CV and RhB rank as the highest when compared with other reported MOFs. In contrast, SCNU-Z2 exhibits an extremely low capacity for anionic dyes MO and AO, making it useful for the separation of anionic and cationic dyes based on a charge-dependent mode. Interestingly, SCNU-Z2 can be used to degrade an anionic dye, MB, within 30 min under darkness at room temperature. The apparent activation energy of the dye degradation reaction is calculated to be approximately 18.96 kJ·mol-1, implying that the catalytic reaction of MB can be considered as a low-temperature thermocatalytic reaction in the dark/SCNU-Z2 system.

6.
Zhonghua Nan Ke Xue ; 21(4): 308-14, 2015 Apr.
Artigo em Zh | MEDLINE | ID: mdl-26027096

RESUMO

OBJECTIVE: To explore the diagnosis, treatment, and prognosis of prostatic malignant mesenchymal tumors (PMMT). METHODS: We retrospectively analyzed the clinical and follow-up data about 20 cases of PMMT and reviewed the literature relevant to the diagnosis, treatment, and prognosis of the disease. RESULTS: Based on the results of pathology and immunohistochemistry, the 20 PMMT cases included leiomyosarcoma (n = 7), rhabdomyosarcoma (n = 5), prostatic stromal sarcoma (n = 3), chondrosarcoma (n = 1), and undifferentiated PMMT (n = 4). Twelve of the patients were treated by radical prostatectomy (3 concurrently by sigmoid colostomy and 1 by cystostomy), 2 by pelvic tumor resection following arterial embolization, 1 by total pelvic exenteration, 1 by colostomy with pelvic lymph node biopsy, and 4 by conservative therapy because of metastasis to the lung, pelvis and bone. Of the 20 patients, 9 died of systemic metastasis within 3 months after treatment, 3 died at 6, 7, and 14 months, respectively, 3 survived with tumor for 5, 11, and 12 months, respectively, 2 survived without tumor for 12 and 24 months so far, all subjected to periodic chemotherapy postoperatively, and 3 lost to follow-up. CONCLUSION: PMMT is a tumor of high malignancy and rapid progression, for which transrectal ultrasound-guided biopsy remains the main diagnostic method. The clinical stage of the tumor is an important factor influencing its prognosis and the survival rate of the patients can be improved by early diagnosis and combined therapy dominated by radical prostatectomy.


Assuntos
Mesenquimoma/patologia , Mesenquimoma/terapia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Terapia Combinada/métodos , Humanos , Imuno-Histoquímica , Masculino , Mesenquimoma/mortalidade , Prognóstico , Prostatectomia , Neoplasias da Próstata/mortalidade , Estudos Retrospectivos
7.
World J Surg Oncol ; 12: 331, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25380562

RESUMO

BACKGROUND: Castleman's disease (CD) is a relatively rare disorder characterized by the benign proliferation of lymphoid tissue. The combination of an occurrence of retroperitoneal pararenal CD with myasthenia gravis (MG) is extremely rare. CASE PRESENTATION: The patient was admitted to our hospital for investigation of a retroperitoneal pararenal tumor which had been coincidentally diagnosed at a local hospital where he was admitted because of MG. The patient subsequently underwent an exploratory laparotomy and suffered from postoperative myasthenic crisis. Pathological examination revealed a left retroperitoneal mass of CD (hyaline vascular type). There was no recurrence of disease found after 7 months. CONCLUSIONS: CD with MG is a rare condition. Postoperative myasthenic crisis is a severe complication. The possibility of its occurrence must be in physicians' minds and the risk of postoperative myasthenic crisis must be carefully considered when evaluating MG patients undergoing surgery.


Assuntos
Hiperplasia do Linfonodo Gigante/complicações , Miastenia Gravis/complicações , Neoplasias Retroperitoneais/complicações , Adulto , Hiperplasia do Linfonodo Gigante/diagnóstico , Hiperplasia do Linfonodo Gigante/cirurgia , Diagnóstico Diferencial , Humanos , Laparotomia , Masculino , Miastenia Gravis/diagnóstico , Miastenia Gravis/cirurgia , Prognóstico , Neoplasias Retroperitoneais/diagnóstico , Neoplasias Retroperitoneais/cirurgia
8.
Chem Commun (Camb) ; 60(48): 6190-6193, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38805194

RESUMO

For the first time, hierarchical porous amorphous metal-organic frameworks (HP-aMOFs) containing ultramicropores, micropores, and mesopores were synthesized by etching a composite of MOF glass (agZIF-76) and ZnO using ammonia. These materials show potential applications in the adsorption of C2 hydrocarbons.

9.
Dalton Trans ; 52(34): 12087-12097, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37581335

RESUMO

The research on amorphous metal-organic frameworks (aMOFs) is still in its infancy, and designing and constructing aMOFs with functional pores remains a challenge. Two aMOFs based on Co(II) and heterotopic triangular ligands with large conjugated aromatic planes, namely aMOF-1 and aMOF-2, were constructed and characterized by IR, XPS, EA, ICP, XANS and so on. aMOF-1 possesses mesopores, whereas aMOF-2 possesses micropores. The porosity, conjugated aromatic plane and uncoordinated N atoms in the framework allow these aMOFs to adsorb iodine and dyes. The iodine adsorption capacity of aMOF-1 is 3.3 g per g, which is higher than that of aMOF-2 (0.56 g per g), mainly due to the expansion or swelling of aMOF-1 after iodine adsorption. The uptake of cationic dyes by aMOF-2 showed more rapid kinetics and a higher removal rate than that by aMOF-1, mainly due to the difference in the porosity and surface charge. Although the surface charges of aMOF-1 and aMOF-2 are negative, both of them showed significantly faster adsorption kinetics toward anionic dyes, among which methyl orange (MO) and Congo red (CR) can be removed in 5 min. This occurs possibly because the quick adsorption of Na+ ions alters the surface charge of the framework and promotes dye uptake. The adsorption capacities of aMOF-1 for MO and CR reached 921 and 2417 mg g-1, respectively. The correlation data for aMOF-2 are 1042 and 1625 mg g-1, respectively. All adsorption capacities are among the highest compared to many cMOFs. Adsorption in mixed dye solution is found to be charge-dependent, kinetic-dependent, and synergetic in these systems. The porosity, surface charge regulation during adsorption, weak interactions and multiple adsorption processes contribute to the dye adsorption performance.

10.
Chem Commun (Camb) ; 59(59): 9118-9121, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37403984

RESUMO

A metal-organic cage (MOC)-based porous salt composed of cationic Zr-MOC and anionic Cu-MOC was incorporated into SBA-15 nanopores via a two-step impregnation method for the first time. The encapsulated MOC-based porous salt showed improved iodine adsorption capacity when compared with the bulk sample.

11.
Acta Crystallogr C ; 68(Pt 7): m177-80, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22763683

RESUMO

The title compound, poly[aqua(µ(2)-1H-imidazole-4-carboxylato-κ(3)N(3),O:O')hemi(µ(2)-oxalato-κ(4)O(1),O(2):O(1'),O(2'))cadmium(II)], [Cd(C(4)H(3)N(2)O(2))(C(2)O(4))(0.5)(H(2)O)](n), exhibits a two-dimensional network. The Cd(II) cation is coordinated to one N atom and two carboxylate O atoms from two 1H-imidazole-4-carboxylate (Himc) ligands, two carboxylate O atoms from the bridging oxalate anion and one ligated water molecule; these six donor atoms form a distorted octahedral configuration. The oxalate anion lies on a centre of inversion. The Himc ligands connect the Cd(II) cations to form -Cd-Himc-Cd-Himc-Cd- zigzag chains, with a Cd···Cd separation of 5.8206 (6) Å along the b direction, which are further linked by tetradentate oxalate anions to generate a two-dimensional herringbone architecture in the ab plane. These layers are extended to form a three-dimensional supramolecular framework via O-H···O and N-H···O hydrogen bonds and π-π stacking interactions. The solid-state photoluminscent behaviour of the title compound has been investigated at room temperature.

12.
Zhonghua Nan Ke Xue ; 18(12): 1119-22, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23405796

RESUMO

OBJECTIVE: To investigate the clinical manifestations, pathological features, diagnosis and treatment of stromal tumor in the seminal vesicle. METHODS: We retrospectively analyzed 1 case of stromal tumor of the seminal vesicle, reviewed relevant domestic and international literature, and summarized the clinical manifestations, pathological features, diagnosis and treatment of the tumor. RESULTS: The patient was a 50 years old male, who underwent excision of the tumor together with the seminal vesicle. Pathology showed it to be stromal tumor of the seminal vesicle. Ultrasonography and CT found no recurrence 10 months after surgery. CONCLUSION: Stromal tumor of the seminal vesicle is rare and easy to be misdiagnosed. Digital rectal examination, and ultrasonography, CT and MRI of the urinary system are useful for its diagnosis. The currently accepted treatment is surgical removal of the tumor, and the prognosis is good.


Assuntos
Cistadenoma , Neoplasias dos Genitais Masculinos , Glândulas Seminais , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
13.
Chempluschem ; 87(8): e202200172, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35922387

RESUMO

Metal-organic cages (MOCs) that assemble from metal ions or metal clusters and organic ligands have attracted the interest of the scientific community because of their various functional coordination cavities. Unlike metal-organic frameworks (MOFs) with infinite frameworks, MOCs have discrete structures, making them soluble and stable in certain solvents and facilitating their application as starting reagents in the further construction of single components or composite materials. In recent years, increasing progress has been made in this field. In this review, we introduce these works from the perspective of design strategies, and focus on how presynthesized MOCs can be used to construct functional materials. Finally, we discuss the challenges and development prospects in this field.


Assuntos
Estruturas Metalorgânicas , Metais , Ligantes , Estruturas Metalorgânicas/química , Metais/química
14.
Chem Commun (Camb) ; 58(32): 5013-5016, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35363232

RESUMO

Two amorphous metal-organic frameworks (aMOFs) were obtained from crystalline Co-MOF (SCNU-Z6) via temperature-induced (aT-SCNU-Z6) and water-immersed (aW-SCNU-Z6) approaches. They exhibited high iodine uptake, with the adsorption capacities of aT-SCNU-Z6 and aW-SCNU-Z6 reaching 2.05 and 5.04 g g-1, respectively. This work is the first report of iodine uptake by aMOFs.


Assuntos
Iodo , Estruturas Metalorgânicas , Adsorção , Iodetos , Estruturas Metalorgânicas/química , Água
15.
J Chromatogr A ; 1675: 463155, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35635867

RESUMO

Porous spherical silica-based chiral stationary phases (CSPs) have been commercially used in the field of chiral separation, however, the scope of their application is, to some extent, limited by the instability of silica towards mobile phase containing strong base or acid. As such, developing new matrix-based CSPs is one of the effective strategies to overcome this bottleneck in studies of chiral separation materials. In this work, we have demonstrated that stable spherical covalent organic frameworks (SCOFs) can be utilized as matrixes for the fabrication of new CSPs for the first time. Specifically, a porous imine-linked SCOF with good crystallinity, large surface area, and high chemical stability is synthesized at room temperature. Then, cellulose-tris (3,5-dimethylphenylcarbamate) (CDMPC), a typical cellulose derivative, is selected as a potential chiral selector and coated onto the robust SCOFs, giving rise to the fabrication of new CDMPC@SCOF CSPs. The as-synthesized stable SCOF-based CSPs are exploited for high-performance liquid chromatographic (HPLC) enantioseparation, showing high resolution abilities for the separation of racemic compounds such as metalaxyl, 1-(1-naphthalenyl)ethanol, epoxiconazol, trans-stilbene oxide, and so on. Moreover, the prepared SCOF-based CSPs exhibit more superior acid and base stability than those of the silica-based CSPs. Our work not only uncovers the great potential of SCOFs as matrixes for constructing novel CSPs, but also expands the application of COFs in the field of enantiomeric separation under harsh base and acid conditions.


Assuntos
Estruturas Metalorgânicas , Celulose/química , Cromatografia Líquida de Alta Pressão/métodos , Dióxido de Silício/química , Estereoisomerismo
16.
Acta Crystallogr C ; 67(Pt 11): m346-50, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22051950

RESUMO

The title compounds, trans-bis(1H-benzimidazole-2-carboxylato-κ(2)N(3),O)bis(ethanol-κO)cadmium(II), [Cd(C(8)H(5)N(2)O(2))(2)(C(2)H(6)O)(2)], (I), and trans-bis(1H-benzimidazole-κN(3))bis(1H-benzimidazole-2-carboxylato-κ(2)N(3),O)nickel(II), [Ni(C(8)H(5)N(2)O(2))(2)(C(7)H(6)N(2))(2)], (II), are hydrogen-bonded supramolecular complexes. In (I), the Cd(II) ion is six-coordinated by two O atoms from two ethanol molecules, and by two O and two N atoms from two bidentate benzimidazole-2-carboxylate (HBIC) ligands, giving a distorted octahedral geometry. The combination of O-H···O and N-H···O hydrogen bonds results in two-dimensional layers parallel to the ab plane. In (II), the six-coordinated Ni(II) atom, which lies on an inversion centre, shows a similar distorted octahedral geometry to the Cd(II) ion in (I); two benzimidazole molecules occupy the axial sites and the equatorial plane contains two chelating HBIC ligands. Pairs of N-H···O hydrogen bonds between pairs of HBIC anions connect adjacent Ni(II) coordination units to form a one-dimensional chain parallel to the a axis. Moreover, these one-dimensional chains are further linked via N-H···O hydrogen bonds between HBIC anions and benzimidazole molecules to generate a three-dimensional supramolecular framework. The two compounds show quite different supramolecular networks, which may be explained by the fact that different co-ligands occupy the axial sites in the coordination units.

17.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 3): o656, 2011 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-21522408

RESUMO

The title compound, C(20)H(32)ClNO(3), was obtained via a tandem asymmetric Michael addition-elimination reaction of (5S)-3,4-dichloro-5-(l-menth-yloxy)furan-2(5H)-one and 4-methyl-piperidine in the presence of potassium fluoride. The furan-one ring is approximately planar [maximum atomic deviation = 0.022 (2) Å] while the cyclo-hexane ring adopts a chair conformation. Weak inter-molecular C-H⋯O hydrogen bonding is present in the crystal structure.

18.
World J Clin Cases ; 9(22): 6388-6392, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34435003

RESUMO

BACKGROUND: Prostatic carcinosarcoma is a very rare and highly aggressive tumor. It may occur after androgen deprivation therapy (ADT) for adenocarcinoma even after a 7-year interval. CASE SUMMARY: A 66-year-old man presented with recurrent symptoms of gross hematuria and urinary retention. The patient had a previous history of combined radical prostatectomy and ADT for prostate cancer 7 years prior. He received total pelvic exenteration for a recurrent pelvic carcinosarcoma. Pathology and immunostaining revealed a carcinosarcoma of prostatic origin with focal spindled cells and bizarre giant cells. The patient subsequently underwent transverse colostomy for carcinosarcoma recurrence and bowel obstruction 3 mo later. Five months after the diagnosis of prostatic carcinosarcoma, the patient died of multiple organ metastases. CONCLUSION: Prostatic carcinosarcoma after adenocarcinoma is exceedingly rare. ADT mediated transformation and dedifferentiation of the epithelial components may be the origin of this malignancy.

19.
Chempluschem ; 86(5): 699, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33734610

RESUMO

Invited for this month's cover are the collaborating groups of Sheng-Run Zheng and Wei-Guang Zhang from South China Normal University, China. The cover picture shows an amorphous cationic porous metal-organic material that constructed from the covalent linking of large cationic metal-organic cage for the removal of toxic oxo-anions from water with high capacities and rapid kinetics. Read the full text of the article at 10.1002/cplu.202000570.

20.
Dalton Trans ; 49(35): 12150-12155, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32840538

RESUMO

A metal-organic framework (MOF), namely SCNU-Z3, based on an imidazole-tetrazole tripodal ligand and Mn(ii), has been constructed. It exhibits a porous 3D framework composed of truncated octahedron cage subunits. Unexpected ligand-induced missing metal-ion defects were observed in the framework. In addition, the application of SCNU-Z3 in a supercapacitor was performed.

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