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Introducing dynamic behavior into periodic frameworks has borne fruit in the form of flexible porous crystals. The detailed molecular design of frameworks in order to control their collective dynamics is of particular interest, for example, to achieve stimulus-induced behavior. Herein, by varying the degree of rigidity of ditopic pillar linkers, two isostructural flexible metal-organic frameworks (MOFs) with common rigid supermolecular building bilayers were constructed. The subtle substitution of single (in bibenzyl-4,4'-dicarboxylic acid; H2BBDC) with double (in 4,4'-stilbenedicarboxylic acid; H2SDC) C-C bonds in pillared linkers led to markedly different flexible behavior of these two MOFs. Upon the removal of guest molecules, both frameworks clearly show reversible single-crystal-to-single-crystal transformations involving the cis-trans conformation change and a resulting swing of the corresponding pillar linkers, which gives rise to Flex-Cd-MOF-1a and Flex-Cd-MOF-2a, respectively. Strikingly, a more favorable gas-induced dynamic behavior in Flex-Cd-MOF-2a was verified in detail by stepwise C3H6/C3H8 sorption isotherms and the corresponding in situ powder X-ray diffraction experiments. These insights are strongly supported by molecular modeling studies on the sorption mechanism that explores the sorption landscape. Furthermore, a consistency between the macroscopic elasticity and microscopic flexibility of Flex-Cd-MOF-2 was observed. This work fuels a growing interest in developing MOFs with desired chemomechanical functions and presents detailed insights into the origins of flexible MOFs.
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Metal-organic frameworks (MOFs) have been recognized as a potential platform for the development of tunable luminophores owing to their highly modulable structures and components. Herein, two MOF luminophores based on Cd(II) ions, 1,3,5-tri(4-pyridinyl)benzene (TPB), and 1,4-dicarboxybenzene (H2BDC) were constructed. The directed assembly of the metal ions and organic linkers results in [Cd2(BDC)2(TPB)(H2O)]·x(solvent) (MOF-1) featuring TPB-based blue fluorescence centered at 425 nm. By introducing anthracene as the structure directing agent (SDA) for assembly regulation, [Cd2(BDC)(TPB)2(NO3)2]·x(solvent) (MOF-2) was obtained, which reveals anthracene feeding-dependent high tunable emission in the 517-650 nm range. Detailed components, photophysical properties, and structural characteristics investigations of MOF-2 indicate the TPB and NO3- interactions as the origin of its redshifted emission compared with that of MOF-1. Furthermore, the fluorescence of MOF-2 was found to be regulatable by the anthracene feeding based on the SDA-determined crystallinity of the crystalline sample. All these results provided a unique example of the structural and fluorescence regulation of MOF luminophores.
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The hierarchical porous metal-organic framework (HP-MOF) has emerged as a hot topic in porous materials in consideration of their advantages in storage capacity and catalysis performance. Herein, we report the construction and property investigation of a series of HP-MOFs. A series of isoreticular microporous MOFs featuring the pacs topology network based on 2,4,6-tris(4-pyridyl)-1,3,5-triazine and different carboxylic acid ligands are found to be potential precursors to construct HP-MOFs. Through the decarboxylation of carboxylate ligands at high temperatures, a hierarchical porous structure could be obtained with the reservation of a crystalline framework. The formation of hierarchical pores is highly dependent on the structural and component nature (carboxylate ligands and metal centers) of the pristine MOF and the pyrolysis conditions (temperature and treatment time), indicating the highly tunable hierarchical pore characteristic of the HP-MOFs. By taking advantage of the increased pore volume and more exposed activation sites, the HP-MOFs reveal enhanced anionic dye adsorption capacity (800 mg·g-1 for Congo red and 140 mg·g-1 for methyl blue) and catalytic activity toward electrocatalytic oxygen reduction reaction (overpotential of 0.302 V at a current density of 10 mA·cm-2, 51 mV lower than that of the pristine MOF).
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The construction and modulation of hierarchical pore structure in metal-organic frameworks (MOFs) has become a hot topic owing to the advantages of hierarchical pore MOFs (HP-MOFs) in matter storage and mass transfer related applications. Herein, we report the engineering of crystalline defect in a bimetallic MOF for the construction and tuning of HP-MOF. A microporous MOF system showing metal-center-dependent water stability, namely, {[M3F(bdc)3 tpt] (solvents)}n (M = Zn2+ and Ni2+, H2bdc = 1,4-benzenedicarboxylic acid, tpt = 2,4,6-tris(4-pyridyl)triazine), was utilized as a platform for the construction of HP-MOF. By tuning the Zn2+/Ni2+ ratio in the reactant, a bimetallic MOF with a highly tunable Zn2+/Ni2+ ratio could be obtained. The relatively labile Zn2+-based coordination bonding in the bimetallic MOF could be readily and targeted broken through water treatment for the engineering of crystalline defects-based hierarchical pore structure. The resultant HP-MOF reveals a dramatically increased pore volume with the presence of mesopore and macropore. In addition, the anionic framework of HP-MOF could be utilized for the selective adsorption of a cationic dye methylene blue, and a relatively high capacity (250 mg·g-1, five times compared with the pristine microporous MOF) could be achieved.
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Objective: To investigate the effects of serum containing Qinbai Qingfei concentrated pellets on expressions of NLRP3 inflammasome in RAW264. 7 cells infected with Mycoplasma pneumoniae( MP) IL-1ß. Methods: RAW264. 7 cells were randomly divided into normal group, MP model group and serum containing Qinbai Qinfei concentrated pellets group. RAW264. 7 cells and MP strain were cultured utilizing normal methods, preparation of serum containing Qinbai,with 1ⶠ10 multiplicity of infection( MOI) of MP stimulation on RAW264. 7 cells; cells of each group were collected at 8,16,24 h respectively. The expressions of NLRP3,ASC and Caspase-1 mRNA were detected by the method of FQ-PCR. The expressions of NLRP3,ASC and Caspase-1 p20 protein were detected by Westernblot. The content of IL-1ß in the supernatant was measured by ELISA. Results: Compared with the normal group, he levels of NLRP3,ASC and Caspase-1 mRNA were significantly increased in the model group at 8,16,24 h respectively( P < 0. 05 or P < 0. 01); while the levels of NLRP3,ASC and Caspase-1 p20 protein were increased significantly( P < 0. 05 or P < 0. 01) at 16,24 h, and the levels of IL-1ß were increased at significantly( P < 0. 01) 24 h. Compared with the model group, the levels of NLRP3,ASC and Caspase-1 mRNA were significantly reduced in serum containing Qinbai Qinfei concentrated pellets group at 16,24 h( P < 0. 05 or P < 0. 01); the expressions of NLRP3,ASC,Caspase-1 p20 protein and the content of IL-1ß were all decreased at 24 h.Conclusion: The mechanism of antiMycoplasma pneumoniae action of Qinbai may be related to the down-regulation of NLRP3 inflammasome expressions.
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Inflamassomos , Medicina Tradicional Chinesa , Animais , Caspase 1 , Regulação para Baixo , Interleucina-1beta , Camundongos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Pneumonia por Mycoplasma , Células RAW 264.7 , RNA MensageiroRESUMO
A new flavonol glycoside, kaempferol-3-O-ß-D-(2-O-E-p-coumaroyl)-glucopyranosyl-7-O-α-l-rhamnopyranoside (1), along with eleven known compounds including five flavonol glycosides (2-6), one phenolic glycoside (7), two megastigmane glycosides (8 and 9), two triterpenoids (10 and 11) and one alditol (12), was isolated from the aerial parts of Euonymus fortunei. Their structures were determined on the basis of spectroscopic analysis and chemical evidence. Compounds 2-4, 7, 8, and 10-12 were evaluated their antimicrobial activities against Ureaplasma urealyticumin vitro, but all tested compounds have no useful activities against Ureaplasma urealyticum.
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Euonymus/química , Flavonóis/isolamento & purificação , Glicosídeos/isolamento & purificação , Antioxidantes/química , Flavonoides/química , Flavonóis/química , Glicosídeos/química , Estrutura MolecularRESUMO
In order to improve the oxidative desulfurization (ODS) performance of MOF materials, an effective way is to convert a microporous MOF into a hierarchical porous MOF (HP-MOF) by utilizing the linker selective retention strategy. Herein, UiO-66 with the introduction of an unstable linker ligand (dihydro-1,2,4,5-tetrazine-3,6-dicarboxylate, dhtz) can selectively remove dhtz ligands to form HP-MOF (HP-UiO-66-dhtz) through heat treatment at high temperature. While maintaining the original structure of UiO-66, HP-UiO-66-dhtz features mesopores and abundant Lewis acid sites, showing excellent ODS performance for diphenylthiophene (DBT).
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Colorectal cancer (CRC) is a common malignant tumor and is one of the three most common cancers worldwide. Traditional surgical treatment, supplemented by chemotherapy and radiotherapy, has obvious side effects on patients. Immunotherapy may lead to some unpredictable complications. Low introduction rate and high cost are some of the problems of gene therapy, so finding a safe, reliable and least toxic treatment method became the main research direction for this study. Lactic acid bacteria and their metabolites are widely used in functional foods or as adjuvant therapies for various diseases because they are safe to eat and have no adverse reactions. Research has shown that lactic acid bacteria and their metabolites play an auxiliary therapeutic role in colorectal cancer mainly by improving the intestinal flora composition, inhibiting the growth of pathogenic bacteria and inhibiting the proliferation of cancer cells. It is now widely believed that the substances that probiotics such as lactic acid bacteria exert anti-cancer effects are mainly secondary metabolites such as butyric acid. Lb. plantarum AY01 isolated from fermented food has good anti-cancer ability, and its main anti-cancer substance is 2'-deoxyinosine. Through flow cytometry detection, it was found that Lb. plantarum AY01 can block cell proliferation in the S phase. In addition, Lb. plantarum AY01 culture reduces the sensitivity of mice to colitis-associated CRC induced by azoxymethane (AOM)/dextran sulfate sodium salt (DSS) and exhibits the occurrence and promotion of tumors. According to transcriptome analysis, Lb. plantarum AY01 may induce apoptosis of colorectal cancer cells by activating the p38 MAPK pathway. This experiment provided possibilities for the treatment of CRC.
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OBJECTIVE: To evaluate the efficacy of arthroscopic surgery in inflammatory hip arthritis. METHODS: A retrospective clinical study was conducted inspecting 40 hips in 36 patients of inflammatory arthritis. There were 17 cases of ankylosing spondylitis, 11 cases of rheumatoid arthritis, and 8 cases of psoriatic arthritis. The joints were irrigated and the inflamed tissues were debrided with anthroscopy. The patients were followed up with Harris hip score, Oxford hip score, Visual Analog Scale (VAS), and magnetic resonance imaging (MRI). Statistical analysis was performed using Student t test. RESULTS: All of the 36 cases were followed up for 46-103 months, averaging 67.2±8.4 months. Harris and Oxford scores increased from 66.9±12.1 and 69.4±16.4 before operation to 78.4±19.3 and 80.2±18.8 after operation, respectively (P<0.05). VAS score decreased from pre-operative 8.5±2.5 to post-operative 7.2±2.5 (P<0.05). All the patients showed improved joint range of motion. MRI revealed alleviation of hip synovitis. The results were classified as excellent in 8 patients, good in 17 patients, fair in 8 patient, and poor in 3 according to Harris hip score. Twenty-seven patients were satisfied with the operative outcomes as they regained normal daily activities. CONCLUSIONS: Arthroscopy-assisted joint debridement and synovium resection is an effective procedure for hip lesion in inflammatory arthritis. The inflammatory lesion might be thereby controlled and the symptoms be relieved.
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Artrite/cirurgia , Artroscopia/métodos , Desbridamento/métodos , Articulação do Quadril/cirurgia , Sinovectomia , Adulto , Artrite/patologia , Artrite/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos RetrospectivosRESUMO
Introduction: Climate change not only directly affects the phenotype of organisms but also indirectly impacts their physiology, for example, by altering their susceptibility to insecticides. Changed diurnal temperature fluctuations are an important aspect of climate change; ignoring the impact of these fluctuations on the biological effects of various chemical insecticides can lead to inaccurate assessments of insecticide risk under the current and future climate change scenarios. Methods: In this study, we studied effects of different temperature amplitudes (± 0, ± 6, ± 12°C) at the same mean temperature (22°C) on the life history traits of a globally distributed pest (Sitobion avenae, wheat aphid), in response to low doses of two insecticides. The first, imidacloprid shows a positive temperature coefficient; the second, beta-cypermethrin has a negative temperature coefficient. Results: Compared with the results seen with the constant temperature (22°C), a wide temperature amplitude (± 12°C) amplified the negative effects of imidacloprid on the survival, longevity, and fecundity of S. avenae, but significantly increased the early fecundity of the wheat aphid. Beta-cypermethrin positively impacted the wheat aphid at all temperature amplitudes studied. Specifically, beta-cypermethrin significantly increased the survival, longevity, and fecundity of S. avenae under medium temperature amplitude (± 6°C). There were no significant differences in the survival, longevity, and the early fecundity of S. avenae when it was treated with beta-cypermethrin at the wide temperature amplitude (± 12°C). However, the negative effect of beta-cypermethrin on the intrinsic rate of increase of S. avenae decreased gradually with the increase in temperature amplitude. Discussion: In conclusion, the response of S. avenae to positive temperature coefficient insecticides was markedly affected by temperature amplitude, while negative temperature coefficient insecticides increased the environmental adaptability of S. avenae to various temperature amplitudes. Our results highlight the importance of the integrated consideration of diurnal temperature fluctuations and different temperature coefficient insecticide interactions in climate-change-linked insecticide risk assessment; these results emphasize the need for a more fine-scale approach within the context of climate change and poison sensitivity.
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BACKGROUND: Mesenchymal stem cells (MSCs) have great potential for the treatment of various immune diseases due to their unique immunomodulatory properties. However, MSCs exposed to the harsh inflammatory environment of damaged tissue after intravenous transplantation cannot exert their biological effects, and therefore, their therapeutic efficacy is reduced. In this challenging context, an in vitro preconditioning method is necessary for the development of MSC-based therapies with increased immunomodulatory capacity and transplantation efficacy. AIM: To determine whether hypoxia and inflammatory factor preconditioning increases the immunosuppressive properties of MSCs without affecting their biological characteristics. METHODS: Umbilical cord MSCs (UC-MSCs) were pretreated with hypoxia (2% O2) exposure and inflammatory factors (interleukin-1ß, tumor necrosis factor-α, interferon-γ) for 24 h. Flow cytometry, polymerase chain reaction, enzyme-linked immunosorbent assay and other experimental methods were used to evaluate the biological characteristics of pretreated UC-MSCs and to determine whether pretreatment affected the immunosuppressive ability of UC-MSCs in coculture with immune cells. RESULTS: Pretreatment with hypoxia and inflammatory factors caused UC-MSCs to be elongated but did not affect their viability, proliferation or size. In addition, pretreatment significantly decreased the expression of coagulation-related tissue factors but did not affect the expression of other surface markers. Similarly, mitochondrial function and integrity were retained. Although pretreatment promoted UC-MSC apoptosis and senescence, it increased the expression of genes and proteins related to immune regulation. Pretreatment increased peripheral blood mononuclear cell and natural killer (NK) cell proliferation rates and inhibited NK cell-induced toxicity to varying degrees. CONCLUSION: In summary, hypoxia and inflammatory factor preconditioning led to higher immunosuppressive effects of MSCs without damaging their biological characteristics.
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The red wine fermentation needs fast and nondestructive techniques, which can help to control the fermentation process and assure the quality of wine. In the present study, near infrared spectroscopy (NIR) and electronic nose (EN) were used to predict the alcohol content during the red wine alcoholic fermentation. Calibration models were developed between instru- mental data and chemical analysis using principal component regression (PCR) and partial least squares regression (PLSR) with cross validation. Good correlations (R > 0.99) were acquired for both the models developed by the NIR and EN data. However, RMSEC and RMSEP were a little larger. Combining NIR and EN can optimize the model and improve the prediction accuracy. The PLSR model based on combined data shows the best correlation (R = 0.999 2), with RMSEC and RMSEP being 0. 206 and 0.205% (v/v), respectively. Both NIR spectroscopy and EN can predict the alcohol concentration during the alcoholic fermentation of red wine, and the combination of two instruments can improve the analysis precision. Although the measurements were carried out in off-line mode, this study demonstrates that NIR and EN can be used as on line, fast, nondestructive and in time techniques to provide in-time information about the fermentation process and to assure the quality of final products.
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Nariz Eletrônico , Etanol/análise , Fermentação , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Vinho/análise , Análise dos Mínimos Quadrados , Análise de Componente PrincipalRESUMO
Background: A diversity of microorganisms is associated with human health and exists in a state of dynamic equilibrium. This diversity has direct implications for the assessment of susceptibility to infectious diseases, especially human papillomavirus (HPV) infection. Methods: Here, we investigated the relationships between HPV infection and vaginal, cervical, and gut microbiota composition and assessed the levels of genital immune mediators. We selected a multiethnic area in Yunnan Province, China, to collect samples from healthy women of childbearing age. A total of 82 healthy women of childbearing age were included in this study. Vaginal, cervical, and rectal swabs were collected to analyze the microbial community, and cytokines were analyzed in some samples. Findings: Different proportions and types of HPV infection were detected in cervical (44%), vaginal (18%), and rectal (18%) swabs. HPV detected in cervical swabs was generally a high-risk type, while low-risk HPV types were primarily detected in vaginal and rectal swabs. There were some differences in this proportion as well as in the microbial community composition among different ethnic groups. Rectal samples exhibited the highest diversity index, while vaginal samples displayed the lowest diversity index. Lactobacillus dominated most of the vaginal samples, was decreased in HPV-positive samples, and differed among different ethnic groups. However, the sequence proportion of Lactobacillus in the cervix exhibited the opposite trend in those affected by HPV infection. The dynamic balance between the potential pathogens Gardnerella and Lactobacillus determines the health of the female genital system. Interpretation: This study constitutes the first step toward personalized medicine for women's reproductive health, wherein differences between the genital microbiomes of individuals would be considered in risk assessment and for subsequent disease diagnosis and treatment.
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Microbiota , Infecções por Papillomavirus , China/epidemiologia , Etnicidade , Feminino , Humanos , Lactobacillus , RNA Ribossômico 16S , VaginaRESUMO
BACKGROUND: Pulmonary thromboembolism (PTE) is a common disease which may be a serious condition and has high mortality. Recently, it has been shown that circRNAs play an important role in the development of various diseases, including thromboembolic disease. However, circRNAs expression profiling is not clear in PTE, this study aims to identify the circRNAs expressed in PTE and to elucidate their possible role in pathophysiology of PTE. METHODS: A total of 5 patients with CTPA-confirmed PTE and 5 healthy controls were recruited for the present study. The circRNAs expression profile was analyzed by microarray. RESULTS: In total, 256 differentially expressed circRNAs (up 142, down114) and 1162 mRNA (up 446, down 716) were summarized by analyzing the circRNAs microarray data. The top 3 up-regulated and 3 down-regulated circRNAs were validated by Real-Time Polymerase Chain Reaction (qRT-PCR). Two differentially expressed circRNAs (hsa_circ_0000891, hsa_circ_0043506) were selected for further analysis. Finally, we construct a circRNA-miRNA-mRNA ceRNA network with a bioinformatic prediction tool. Pathway analysis shows that the enriched mRNAs targets take part in Protein processing in endoplasmic reticulum, Systemic lupus erythematosus, Endocytosis, Spliceosome, HTLV-I infection and Ubiquitin mediated proteolysis. CONCLUSION: Our findings indicated that aberrantly expressed circRNAs (hsa_circ_0000891, hsa_circ_0043506) may be involved in the development of PTE.
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A released exopolysaccharide (rEPS)-producing strain (LM187) with good acid resistance, bile salt resistance, and cholesterol-lowering properties was isolated from Sichuan paocai and identified as Leuconostoc mesenteroides subsp. mesenteroides. The purified rEPS, designated as rEPS414, had a uniform molecular weight of 7.757 × 105 Da. Analysis of the monosaccharide composition revealed that the molecule was mainly composed of glucose. The Fourier transform-infrared spectrum showed that rEPS414 contained both α-type and ß-type glycosidic bonds. 1H and 13C nuclear magnetic resonance spectra analysis showed that the purified rEPS contained arabinose, galactose, and rhamnose, but less uronic acid. Scanning electron microscopy demonstrated that the exopolysaccharide displayed a large number of scattered, fluffy, porous cellular network flake structures. In addition, rEPS414 exhibited strong in vitro antioxidant activity. These results showed that strain LM187 and its rEPS are promising probiotics with broad prospects in industry.
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Antioxidantes/farmacologia , Leuconostoc/metabolismo , Polissacarídeos Bacterianos/farmacologia , Probióticos , Antioxidantes/química , Antioxidantes/isolamento & purificação , Antioxidantes/metabolismo , Alimentos Fermentados/microbiologia , Leuconostoc/isolamento & purificação , Peso Molecular , Monossacarídeos/química , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/metabolismoRESUMO
To produce a vaccine suitable for human use, a recombinant non His-tagged isoform of the Hc domain of botulinum neurotoxin serotype F (rFHc) was expressed in Escherichia coli and purified by sequential chromatography. The rFHc was evaluated as a subunit vaccine candidate in mouse model of botulism. A dose-response was observed in both antibody titer and protective efficacy with increasing dosage of rFHc and number of vaccinations. These findings suggest that the rFHc is an effective botulism vaccine candidate. Further, we developed a new antitoxin against botulinum neurotoxin serotype F (BoNT/F) by purifying F(ab')(2) fragments from pepsin digested serum IgGs of horses inoculated with rFHc. The protective effect of the F(ab')(2) antitoxin against BoNT/F was determined both in vitro and in vivo. The results showed that the F(ab')(2) antitoxin could prevent botulism in mice challenged with BoNT/F and effectively delayed progression of paralysis from botulism in the therapeutic setting. Thus, our results provide valuable experimental data for this new antitoxin as a potential candidate for treatment of botulism caused by BoNT/F.
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Antitoxina Botulínica/imunologia , Toxinas Botulínicas/imunologia , Botulismo/prevenção & controle , Botulismo/terapia , Vacinas de Subunidades Antigênicas/imunologia , Animais , Anticorpos/sangue , Anticorpos/imunologia , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Antitoxina Botulínica/uso terapêutico , Toxinas Botulínicas/genética , Toxinas Botulínicas/metabolismo , Toxinas Botulínicas/toxicidade , Botulismo/imunologia , Reações Cruzadas/imunologia , Escherichia coli/genética , Escherichia coli/metabolismo , Cavalos , Soros Imunes/imunologia , Imunização Passiva , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos Fab das Imunoglobulinas/uso terapêutico , Imunoglobulina G/sangue , Camundongos , Domínios e Motivos de Interação entre Proteínas/genética , Domínios e Motivos de Interação entre Proteínas/imunologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Organismos Livres de Patógenos Específicos , VacinaçãoRESUMO
5-(1H-Tetrazol-1-yl)isophthalic acid (H(2)L) reacts with Cu(II) ion forming a new metal-organic framework {[CuL]·DMF·H(2)O}(∞) (1) (DMF = N,N-dimethylformamide), with a rutile-related type net topology. Compound 1 possesses a 3D structure with 1D channels that can be desolvated to yield a microporous material. Adsorption properties (N(2), H(2), O(2), CO(2), and CH(4)) of the desolvated solid [CuL] (1a) have been studied, and the results exhibit that 1a possesses fairly good capability of gas sorption for N(2), H(2), O(2), and CO(2) gases, with high selectivity ratios for O(2) over H(2) at 77 K and CO(2) over CH(4) at 195, 273, and 298 K. Furthermore, 1a has excellent O(2) uptake at 77 K and a remarkably high quantity of adsorption for CO(2) at room temperature (298 K) and atmospheric pressure, suggesting its potential applications in gas separation or purification.
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The synergy of a stretchy ligand and highly variable π-π interaction has been proposed as a rational strategy for the construction of breathing metal-organic frameworks (MOFs). Based on this strategy, a breathing MOF, {[Cd2(AzDC)2(TPT)2](DMF)3} n, was successfully constructed with stretchy 4,4'-diazene-1,2-diyldibenzoate acid (H2AzDC) and 2,4,6-tris(4-pyridyl)triazine (TPT) as a source of the π-π interaction. The MOF features structure transformation upon stimulation with solvent guests and varied temperatures, which is straightforwardly characterized by single-crystal structures. Moreover, the solvent-free framework shows breathing behaviors in response to light hydrocarbon (C2H4, C2H6, C3H6, and C3H8) sorption, which was verified by stepwise sorption isotherms and in situ powder X-ray diffraction. Additional investigation of the sorption selectivity of C3/C2 systems indicated that the selectivity can be regulated by the modulation of the dynamic breathing behaviors, which can be used for the selective separation of C3/C2 light hydrocarbons.
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In the title compound, [Zn(C(8)H(5)N(4)O(2))(2)(CH(3)OH)(2)(H(2)O)(2)]·2H(2)O, the Zn(II) ion lies on an inversion centre and is coordinated by two O atoms from two 4-(tetra-zol-1-yl)benzoate ligands, two O atoms from two methanol mol-ecules and two O atoms from two water mol-ecules in a slightly distorted octa-hedral geometry. In addition, there are two uncoordinated water mol-ecules in the crystal structure. The crystal structure is stabilized by inter-molecular O-Hâ¯O hydrogen bonds.
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OBJECTIVES: To investigate the effective method for the calculation of intraocular lens power retrospectively from post-LASIK cases. METHODS: It was a retrospective case series. 40 eyes of 28 patients (14 male and 14 Female) had the Phacoemulsification post-LASIK in HongKong Sanitorium & Hospital; the age ranged from 41.00 to 69.00 years ages, (50.68 +/- 6.56) years. LASIK was done from January, 1997 to April, 2005. Phacoemulsification was done from October, 2000 to September, 2005. RESULTS: Average axial length was (28.06 +/- 1.98) mm (rang from 24.28 to 31.96 mm). The initial refraction power (Spherical Equivalent, SE) before LASIK was from -3.13 to -18.00 D, (-10.44 +/- 3.93) D. K value pre-LASIK was 41.40 to 46.90 D, (43.57 +/- 1.47) D. The best corrected visual acuity (BCVA) preLASIK was 20/20 in 19 eyes, 20/25 in 10 eyes, 20/30 in 7 eyes and 20/40 in 4 eyes. The refraction power of 6 months post-LASIK (SE) was -2.83 to +1.25 D, (-0.32 +/- 0.95) D. The refraction power pre-phaco (SE) was -5.75 to +1.13 D, (-2.35 +/- 2.16) D. The calculated K1 (KpreLASIK-RpostLASIK + RpreLASIK) was 27.60 to 40.70 D, (34.62 +/- 3.56) D. The K from the IOLmaster (K2) was 32.39 to 43.53 D, (38.04 +/- 2.45) D. The target refraction of K1 was -3.69 to 0.61 D, (-1.32 +/- 1.00) D, the target refraction of K2 was -3.67 approximately 3.95 D, (-0.60 +/- 1.84) D. There was significant difference between these two target refraction, (t = -2.40, P = 0.02). The refraction power of post-phaco (> 3 months) was -4.50 to +1.75 D, (-1.10 +/- 1.51) D. The BCVA post-Phaco was 20/20 in 20 eyes, 20/25 in 9 eyes, 20/30 in 5 eyes and 20/40 in 6 eyes. CONCLUSIONS: The formula used in the study for the calculation of intraocular lens power is accurate and effective.