Orthogonal-array dynamic molecular sieving of propylene/propane mixtures.

Rigid molecular sieving materials work well for small molecules with the complete exclusion of large ones1-3, and molecules with matching physiochemical properties may be separated using dynamic molecular sieving materials4-6. Metal-organic frameworks (MOFs)7-9 are known for their precise control of structures and functions on a molecular level10-15. However, the rational design of local flexibility in the MOF framework for dynamic molecular sieving remains difficult and challenging. Here we report a MOF material (JNU-3a) featuring one-dimension channels with embedded molecular pockets opening to propylene (C3H6) and propane (C3H8) at substantially different pressures. The dynamic nature of the pockets is revealed by single-crystal-to-single-crystal transformation upon exposure of JNU-3a to an atmosphere of C3H6 or C3H8. Breakthrough experiments demonstrate that JNU-3a can realize high-purity C3H6 (≥99.5%) in a single adsorption-desorption cycle from an equimolar C3H6/C3H8 mixture over a broad range of flow rates, with a maximum C3H6 productivity of 53.5 litres per kilogram. The underlying separation mechanism-orthogonal-array dynamic molecular sieving-enables both large separation capacity and fast adsorption-desorption kinetics. This work presents a next-generation sieving material design that has potential for applications in adsorptive separation.

Cage-Interconnected Metal-Organic Framework with Tailored Apertures for Efficient C2H6/C2H4 Separation under Humid Conditions.

Metal-organic frameworks (MOFs) with open metal sites (OMSs) have been shown to preferentially adsorb unsaturated hydrocarbons such as C2H4 due to the formation of π-complexation. However, the adsorption capacity and selectivity might well be dampened under humid conditions because OMSs could be easily poisoned in the presence of water vapor. C2H6-selective adsorbents with less hydrophilic environments, on the other hand, not only could effectively minimize the impact of humidity on separation capacity but also could directly produce high-purity C2H4 from C2H6/C2H4 mixtures. Here, we report a C2H6-selective MOF (JNU-2) underlying a rare xae topology. Its cage-like cavities are interconnected through apertures with a limiting diameter of ca. 3.7 Å, which is in the domain of kinetic diameters of C2H4 and C2H6 molecules. Molecular modeling studies suggest the four oxygen atoms on aperture are poised to preferentially interact with C2H6 through multiple C-H···O hydrogen bonding, rendering JNU-2 an enhanced C2H6 selectivity. Indeed, experimental results reveal that JNU-2 not only takes up a great amount of C2H6 comparable to other top-performing C2H6-selective MOFs but also displays excellent separation capacity even under humid conditions; moreover, it can be easily regenerated at room temperature owing to its moderate adsorption enthalpy. This work successfully demonstrated a strategy of balancing adsorption capacity and selectivity for C2H6 by designing MOF materials with cavities interconnected through tailored apertures. The apertures function as screening sites for C2H6 selectivity, while the internal cavities provide space for large adsorption.

Induced Fit of C2 H2 in a Flexible MOF Through Cooperative Action of Open Metal Sites.

Porous materials that can undergo pore-structure adjustment to better accommodate specific molecules are ideal for separation and purification. Here, we report a stable microporous metal-organic framework, JNU-1, featuring one-dimensional diamond-shaped channels with a high density of open metal sites arranged on the surface for the cooperative binding of acetylene. Together with its framework flexibility and appropriate pore geometry, JNU-1 exhibits an induced-fit behavior for acetylene. The specific binding sites and continuous framework adaptation upon increased acetylene pressure are validated by molecular modeling and in situ X-ray diffraction study. This unique induced-fit behavior endows JNU-1 with an unprecedented increase in the acetylene binding affinity (adsorption enthalpy: up to 47.6 kJ mol-1 at ca. 2.0 mmol g-1 loading).

Should diabetic ketosis without acidosis be included in ketosis-prone type 2 diabetes mellitus?

BACKGROUND: The incidence of ketosis-prone type 2 diabetes is very low except for people of sub-Saharan African origin and African Americans. However, there also are some type 2 diabetes patients with diabetic ketosis without acidosis (DKWA). We question whether DKWA should be included as a subtype of ketosis-prone type 2 diabetes mellitus and compared the clinical characteristics of DKWA and diabetic ketoacidosis (DKA) patients. METHODS: The study population consisted of 594 consecutive unrelated Chinese inpatients with newly diagnosed type 2 diabetes. Demographic and clinical characteristics (age, gender, family history of diabetes, body mass index, blood pressure and plasma lipid parameters) were recorded. The patients were divided into ketosis-resistant diabetes (KRD), DKWA and DKA groups on the basis of urinary ketones, blood pH and bicarbonate levels. The blood glucose and c-peptide levels of the patients were also evaluated. RESULTS: The prevalence of KRD, DKWA and DKA were 78.33%, 19.72% and 1.95%, respectively, in the study population. The clinical characteristics of patients with DKWA group patients were similar to those with DKA, except that DKA patients had higher blood glucose and deteriorated ß cell function. CONCLUSIONS: Diabetic ketosis without acidosis and DKA patients share similar clinical characteristics; DKWA should be considered ketosis-prone type 2 diabetes. Therefore, the prevalence of ketosis-prone type 2 diabetes might be underestimated.

Surface engineering on a microporous metal-organic framework to boost ethane/ethylene separation under humid conditions.

Recently, examples of metal-organic frameworks (MOFs) have been identified displaying ethane (C2H6) over ethylene (C2H4) adsorption selectivity. However, it remains a challenge to construct MOFs with both large C2H6 adsorption capacity and high C2H6/C2H4 adsorption selectivity, especially under humid conditions. Herein, we reported two isoreticular MOF-5 analogues (JNU-6 and JNU-6-CH3) and their potential applications in one-step separation of C2H4 from C2H6/C2H4 mixtures. The introduction of CH3 groups not only reduces the pore size from 5.4 Å in JNU-6 to 4.1 Å in JNU-6-CH3 but also renders an increased electron density on the pyrazolate N atoms of the organic linker. JNU-6-CH3 retains its framework integrity even after being immersed in water for six months. More importantly, it exhibits large C2H6 adsorption capacity (4.63 mmol g-1) and high C2H6/C2H4 adsorption selectivity (1.67) due to the optimized pore size and surface function. Breakthrough experiments on JNU-6-CH3 demonstrate that C2H4 can be directly separated from C2H6/C2H4 (50/50, v/v) mixtures, affording benchmark productivity of 22.06 and 18.71 L kg-1 of high-purity C2H4 (≥99.95%) under dry and humid conditions, respectively.

Expression and clinical significance of antiapoptotic gene (survivin) in NB4 and acute promyelocytic leukemia cells.

To study survivin gene expression in APL cells and to explore its correlation with clinical manifestations. PML/RARα and survivin mRNA expression were analysed using RT-PCR. By treatment of ATRA, the survivin mRNA expression in NB4 cells gradually decreased with time and was almost undetectable in the 72th hour. Survivin was expressed in 67% of the 36 APL cases (de novo and relapse patients) with PML/RARα fusion gene expression. However, in 22 cases of remission stage patients without PML/RARα fusion gene expression, survivin was expressed in 36%. The survivin mRNA expression positive rate in de novo and relapse groups, and PML/RARα fusion gene L-type positive groups, was obviously higher than those in remission period groups and was significantly lower than those in acute leukemia groups. In 36 cases of de novo and relapse APL patients, all cases could obtain complete remission, irrespective of the survivin expression. APL patients expressed with survivin mRNA had DIC and serious infection (one patient died). The clinical symptom included slight skin or mucosa bleeding, fever, and asthenic for patients without the survivin mRNA expression. Later, two cases of APL patients with the survivin mRNA expression were treated by ATRA, induction differentiation sign in their peripheral blood and bone marrow figure was not obvious. It was concluded that the survive gene expression was lower in APL than those in any other types of leukemia, thus closely associated with clinical manifestation.

Spatial disposition of square-planar mononuclear nodes in metal-organic frameworks for C2H2/CO2 separation.

The efficient separation of acetylene (C2H2) from its mixture with carbon dioxide (CO2) remains a challenging industrial process due to their close molecular sizes/shapes and similar physical properties. Herein, we report a microporous metal-organic framework (JNU-4) with square-planar mononuclear copper(ii) centers as nodes and tetrahedral organic linkers as spacers, allowing for two accessible binding sites per metal center for C2H2 molecules. Consequently, JNU-4 exhibits excellent C2H2 adsorption capacity, particularly at 298 K and 0.5 bar (200 cm3 g-1). Detailed computational studies confirm that C2H2 molecules are indeed predominantly located in close proximity to the square-planar copper centers on both sides. Breakthrough experiments demonstrate that JNU-4 is capable of efficiently separating C2H2 from a 50 : 50 C2H2/CO2 mixture over a broad range of flow rates, affording by far the largest C2H2 capture capacity (160 cm3 g-1) and fuel-grade C2H2 production (105 cm3 g-1, ≥98% purity) upon desorption. Simply by maximizing accessible open metal sites on mononuclear metal centers, this work presents a promising strategy to improve the C2H2 adsorption capacity and address the challenging C2H2/CO2 separation.

Real-Time Flash Glucose Monitoring Had Better Effects on Daily Glycemic Control Compared With Retrospective Flash Glucose Monitoring in Patients With Type 2 Diabetes on Premix Insulin Therapy.

Background and Aims: To compare the effects of real-time and retrospective flash glucose monitoring (FGM) on daily glycemic control and lifestyle in patients with type 2 diabetes on premix insulin therapy. Methods and Results: A total of 172 patients using premix insulin, with HbA1c ≥ 7.0% (56 mmol/mol), or the time below the target (TBR) ≥ 4%, or the coefficient of variation (CV) ≥36% during the screening period, were randomly assigned to retrospective FGM (n = 89) or real-time FGM group (n = 83). Another two retrospective or real-time 14-day FGMs were performed respectively, 1 month apart. Both groups received educations and medication adjustment after each FGM. Time in range (3.9~10.0 mmol/l, TIR) increased significantly after 3 months in the real-time FGM group (6.5%) compared with the retrospective FGM group (-1.1%) (p = 0.014). HbA1c decreased in both groups (both p < 0.01). Real-time FGMs increased daily exercise time compared with the retrospective group (p = 0.002). Conclusions: Real-time FGM with visible blood glucose improves daily glycemic control and diabetes self-care behaviors better than retrospective FGM in patients with type 2 diabetes on premix insulin therapy. Clinical Trial Registration: https://clinicaltrials.gov/NCT04847219.

Optimizing supramolecular interactions in metal-organic frameworks for C2 separation.

C2 separation is of great importance in the petrochemical industry. Traditionally, it is performed by distillation at cryogenic temperatures, which necessitates the consumption of a huge amount of energy to operate the refrigeration system in the production process. In this regard, it is imperative to seek alternative separation methods with high efficiency and low energy cost. Although of recent origin, metal-organic frameworks (MOFs) have already been extensively studied as advanced adsorbents in many applications, and significant progress has been made particularly in gas separation owing to their unprecedented porosity and tunable structures. In this review, we extrapolated three most frequently invoked design strategies for efficient C2 separation hinged upon supramolecular interactions, including molecular sieving, gate opening, and surface engineering. Recent progress of MOF materials in C2 separation was highlighted within each of these strategies, and their advantages and limitations are compared and discussed. Accordingly, we provide perspectives on current challenges and future emphases in designing MOF materials for hydrocarbon separation. With our continued efforts in this area, we expect that integrating supramolecular interactions in a single MOF system is a viable approach to achieve a balance between adsorption capacity and selectivity for different hydrocarbon separation scenarios.

A clinical and experimental study of adult hereditary spherocytosis in the Chinese population.

Hereditary spherocytosis (HS) is often misdiagnosed due to lack of specific diagnostic methods. Our study summarized clinical characteristics and described the diagnostic workflow for mild and moderate HS in Chinese individuals, using data from 20 adults, 8 of whom presented a familial history for HS. We used scanning electron microscopy (SEM) to diagnose HS. We observed reduced eosin maleimide fluorescence activity (5.50 mean channel fluorescence (MCF) units) in the 10 cases of HS, which differed significantly when compared with 10 normal adults (15.50 units), iron deficiency anemia (15.50 MCF units), and megaloblastic anemia (12.00 MCF units) values (P < .05). Next generation sequencing results revealed that 9 out of 10 patients were found to have mutations in the spectrin alpha chain (SPTB), anchor protein (ANK1), and SLC4A1 genes. These mutations were not reported in the Human Gene Mutation Database (HGMD), 1000 human genome, ExAC, and dbSNP147 databases. Splenectomy proved to be beneficial in alleviating HS symptoms in 10 cases. It was found that for the diagnosis of HS, SEM and next generation gene sequencing method proved to be more ideal than red blood cell membrane protein analysis using sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blotting.

Lipoprotein-associated phospholipase A2 is a risk factor for diabetic kidney disease.

AIMS: This study aimed to determine the association between lipoprotein-associated phospholipase A2 (Lp-PLA2), a marker for inflammation in the vessel wall and independently associated with atherosclerosis, and the incidence of diabetic kidney disease (DKD) in patients with type 2 diabetes (T2D). METHODS: A total of 1452 patients were enrolled in this retrospective cross­sectional study. We recruited patients with T2D who were tested for glycated hemoglobin, fasting and 2 h post-meal serum C-peptide, blood lipid profile, 24 h urine albumin excretion rate (UAER), blood creatine, blood albumin, uric acid, and Lp-PLA2. RESULTS: Among the patients with T2D, 40.3% were diagnosed with DKD and the correlation between DKD and Lp-PLA2 was the most significant one compared to other diabetic complications (odds ratio = 1.651, P < 0.001). Plasma Lp-PLA2 level in patients with DKD was significantly higher and increased Lp-PLA2 level was independently associated with the incidence of DKD after adjustment for age, gender, duration of diabetes, glycated hemoglobin, body mass index, blood lipids, blood pressure, presence of coronary heart disease and carotid plaque, and use of statins (odds ratio = 1.545, P = 0.013). Lp-PLA2 was found to be positively correlated with UAER (r = 0.123, P < 0.001) and negatively correlated with estimated glomerular filtration rate (eGFR) (r = -0.71, P = 0.009). CONCLUSIONS: Increased plasma level of Lp-PLA2 is associated with incidence and development of DKD in patients with T2D. Lp-PLA2 should be considered as a biomarker for early detection and follow-up of DKD. TRIAL REGISTRATION: clinicaltrials.gov, No. NCT03362112, Registered 30 November 2017, retrospectively registered.

[Predicating the sensibility of patients with multiple myeloma to glucocorticoid by cochaperone P23].

This study was aimed to investigate the sensitive index for predicting the sensitivity of patients with multiple myeloma (MM) to glucocorticoid (GC). MM1.S, MM1.R cell lines and 10 MM patients sensitive or non-sensitive to GC were enrolled in this study. The expression of heat shock protein 90 (HSP90) and P23 in peripheral blood mononuclear cells (PBMNC) of MM patients was detected by Western blot, and its relation with GC resistance was explored. The results showed that there were no differences in HSP90, GR and IκB-α expressions among MM1.S, MM1.R, PBMNC of normal persons and MM patients, while there was apparent difference in P23; along with increasing of dexamethasone dose, the survival rate of MM1.S decreased, but that of MM1.R did not change so obviously. Among 7 cases with P23 low expression, combination treatment scheme with GC was effective in 6 cases (86%), uneffective in 1 cases (14%); while among 3 cases with P23 high expression, 1 cases (33%) showed effective to combination treatment with GC, 2 cases (67%) showed uneffective (P < 0.05). It is concluded that the P23 expression may predict the sensitivity of MM patients to GC and may be used as index for guiding clinical treatment.

Prevention of relapse of Graves' disease by treatment with an intrathyroid injection of dexamethasone.

INTRODUCTION: Antithyroid drugs are widely used in the treatment of Graves' disease (GD), but the relapse rate is very high after therapy withdrawal. We evaluated the reduction effects of intrathyroid injection of dexamethasone (IID) on the relapse rate of hyperthyroidism in patients with newly diagnosed GD. PATIENTS AND METHODS: A total of 191 patients with GD completed the study. After 6 months of treatment with methimazole (MMI), the patients were randomly assigned to receive either MMI (96 patients) alone or MMI combined with IID (MMI+IID; 95 patients) treatment for 3 months, followed by continuing a dose of MMI that would maintain euthyroidism for the next 9 months in all of the patients. After withdrawal of the medical therapy, patients were followed for 24 months, and the relapse rate of hyperthyroidism was evaluated. RESULTS: No statistical difference was observed in the levels of serum FT(4), TSH, or TSH receptor antibodies (TR-Ab), the thyroid volume, or the TR-Ab positive rate between the two groups at month 6. After the next 3 months of treatment with MMI+IID or MMI alone, the levels of TSH increased significantly, and the levels of serum TR-Ab, the TR-Ab positive rate, and thyroid volume decreased significantly in the MMI+IID group compared with the MMI group. Seven patients (7.4%) experienced a relapse of overt hyperthyroidism in the MMI+IID group and 49 patients (51%) in MMI group during the 2-yr follow-up period (P < 0.001). CONCLUSIONS: MMI+IID treatment is helpful to prevent relapse of hyperthyroidism in GD after medical therapy withdrawal.