Introducing Carborane Clusters into Crystalline Frameworks via Thiol-Yne Click Chemistry for Energetic Materials.

Crystalline frameworks represent a cutting-edge frontier in material science, and recently, there has been a surge of interest in energetic crystalline frameworks. However, the well-established porosity often leads to diminished output energy, necessitating a novel approach for performance enhancement. Thiol-yne coupling, a versatile metal-free click reaction, has been underutilized in crystalline frameworks. As a proof of concept, we herein demonstrate the potential of this approach by introducing the energy-rich, size-matched, and reductive 1,2-dicarbadodecaborane-1-thiol (CB-SH) into an acetylene-functionalized framework, Zn(AIm)2, via thiol-yne click reaction. This innovative decoration strategy resulted in a remarkable 46.6 % increase in energy density, a six-fold reduction in ignition delay time (4 ms) with red fuming nitric acid as the oxidizer, and impressive enhancement of stability. Density functional theory calculations were employed to elucidate the mechanism by which CB-SH promotes hypergolic ignition. The thiol-yne click modification strategy presented here permits engineering of crystalline frameworks for the design of advanced energetic materials.

Cooperative Catalysis between Dual Copper Centers in a Metal-Organic Framework for Efficient Detoxification of Chemical Warfare Agent Simulants.

Chemical warfare agents (CWAs) are among the most lethal chemicals known to humans. Thus, developing multifunctional catalysts for highly efficient detoxification of various CWAs is of great importance. In this work, we developed a robust copper tetrazolate metal-organic framework (MOF) catalyst containing a dicopper unit similar to the coordination geometry of the active sites of natural phosphatase and tyrosinase enzymes. This catalyst aided in phosphate ester bond hydrolysis and hydrogen peroxide decomposition, ultimately achieving high detoxification efficiency against both a nerve agent simulant (diethoxy-phosphoryl cyanide (DECP)) with a half-life of 3.5 min and a sulfur mustard simulant (2-chloroethyl ethyl sulfide (CEES)) with a half-life of 4.5 min, making it competitive with other reported materials. The dicopper sites in ZZU-282 provide versatile binding modes with the substrates, thereby promoting the activation of substrates and enhancing the catalytic efficiency. A combination of postmodified metal exchange control experiments, density functional theory calculations, and catalytic evaluations confirmed that dual Cu sites are the active centers promoting the catalytic reaction. This study offers a new design perspective to achieve advanced catalysts for CWA detoxification.

Phosphate anion-induced silver-chalcogenide cluster-based metal organic frameworks as dual-functional catalysts for detoxifying chemical warfare agent simulants.

Two porphyrinic silver-chalcogenide cluster-based MOFs were achieved using a phosphate anionic template strategy, and the highly photoactive organic building modules combined with Lewis acidic silver clusters allow both SCC-MOFs to be used as versatile catalysts for the simultaneous degradation of sulfur mustard and nerve agent simulants.

Clinical characteristics and outcomes of COVID-19 long-term nucleic acid positive patients.

OBJECTIVE: This study aimed to investigate the clinical characteristics and outcomes of coronavirus disease-19 (COVID-19) long-term nucleic acid positive patients (hereinafter referred to as CLTAPs). METHODS: Patients were recruited from the Xiaogan Central Hospital between 16 January 2020 and 28 March 2020. Among the 562 cases of patients with laboratory-identified COVID-19 infection by real-time polymerase chain reaction (qtPCR), 19 cases of COVID-19 patients with more than 41 days from the first to the last time of nucleic acid test were selected as the study group, and 76 cases of age- and gender-matched COVID-19 patients were selected as the control group (hereinafter referred to as C-CLTAPs). Demographic characteristics, clinical symptoms, laboratory examination and computed tomography (CT) imaging characteristics were retrospectively analyzed. RESULTS: On admission, among the 562 cases of patients with COVID-19, there were 398 cases of ordinary COVID-19 patients, 99 cases of severe COVID-19 patients and 99 cases of critical COVID-19 patients. CLTAPs had milder clinical symptoms and longer viral shedding time in comparison to C-CLTAPs. Compared to C-CLTAPs, CLTAPs had a lower infection index at admission. CLTAPs used less oxygen therapy and a higher proportion of hydroxychloroquine treatment in comparison to C-CLTAPs. In comparison to C-CLTAPs, CLTAPs showed slower pulmonary CT progression and faster pulmonary CT absorption. CONCLUSION: In this study, out of the 562 cases, we found 19 CLTAPs. The clinical differences between CLTAPs and C-CLTAPs were compared and analyzed. We hope that these finding can provide a theoretical basis for the treatment of CLTAPs.

Ozone Decomposition by a Manganese-Organic Framework over the Entire Humidity Range.

Ground-level ozone (O3) is one of the main airborne pollutants detrimental to human health and ecosystems. However, the designed synthesis of high-performance O3 elimination catalysts suitable for broadly variable air compositions, especially a variable water vapor content, remains daunting. Herein, we report a new manganese-based metal organic framework, [Mn3(µ3-OH)2(TTPE)(H2O)4]·2H2O (H4TTPE = 1,1,2,2-tetrakis(4-(2H-tetrazol-5-yl)phenyl) ethane), denoted as ZZU-281. ZZU-281 catalyzes O3 decomposition with a nearly constant 100% working efficiency over the entire humidity range from dry (≤5% relative humidity (RH)) to high humidity (90% RH). We found that the maintainable coordinated water molecules and OH groups are activated by Mn2+, becoming active sites for O3 transfer to O2 with a low activation energy. The unique open channels, water retainability, and water stability of ZZU-281 further support the high catalytic performance. This work opens a new avenue for designing efficient catalysts for O3 elimination in practice.

Analysis of clinical features and pulmonary CT features of coronavirus disease 2019 (COVID-19) patients with diabetes mellitus.

INTRODUCTION: The objective of this paper was to investigate the clinical features and pulmonary CT imaging features of COVID-19 patients with diabetes mellitus. MATERIAL AND METHODS: From January 16, 2020 to March 28, 2020, among the 568 cases of COVID-19 patients diagnosed in Xiaogan Central Hospital, 64 cases of COVID-19 patients with diabetes were selected as the diabetic group, and 64 cases of COVID-19 patients with age and gender matching without diabetes were selected as the non-diabetic group, and their clinical data and pulmonary CT characteristics were retrospectively analysed. RESULTS: Compared with the non-diabetic group, the proportion of patients in the diabetic group with chronic underlying disease was higher, and they were in more a serious condition at admission. Inflammation index and characteristics of glycolipid metabolism results showed that COVID-19 patients with diabetes mellitus were more likely to have elevated inflammatory markers and hypercoagulability, accompanied by hypoproteinaemia and glucose and lipid metabolism disorders. Treatment and clinic outcome results showed that the time of nucleic acid turning negative in the diabetic group was significantly longer than that in the non-diabetic group. Radiological data showed that COVID-19 combined with diabetes prolonged the time of detoxification in patients. CONCLUSION: COVID-19 patients with diabetes mellitus and chronic hypertension are associated with increased inflammatory markers and disorders of glucose and lipid metabolism. These patients tend to develop serious diseases, especially the rapid progression of CT lesions in the lungs of patients with a wide range ofinvolvement, and prolonged absorption and detoxification time.

Convalescent plasma therapy in critically ill coronavirus disease 2019 patients with persistently positive nucleic acid test, case series report.

INTRODUCTION: Globally, the coronavirus disease 2019 (COVID-19) is still spreading rapidly. At present, there are no specifically approved therapeutic agents or vaccines for its treatment. Previous studies have shown that the convalescent plasma therapy (CPT) is effective in patients with COVID-19. However, its efficacy in patients with persistently positive nucleic acid test is unknown. PATIENT CONCERNS: In this report, we present the clinical data of 5 critically ill COVID-19 patients admitted, between January 16 and February 26, 2020, in intensive care unit of Xiaogan Central Hospital. DIAGNOSIS AND INTERVENTIONS: All these patients had a persistently positive nucleic acid test and received CPT. All 5 patients had severe respiratory failure, and thus, required invasive mechanical ventilation. The median time from the onset of symptoms to initiating the CPT was 37 (Interquartile range, 34-44) days. OUTCOMES: Only 2 patients were cured and subsequently discharged, while 3 patients succumbed due to multiple organ failure. CONCLUSION: The time of initiating the CPT may be an important factor affecting its efficacy, and its therapeutic effect in the treatment of COVID-19, in the late stage, is limited.

A Highly Stable Two-Dimensional Copper(II) Organic Framework for Proton Conduction and Ammonia Impedance Sensing.

This work reports the design and fabrication of a proton conductive 2D metal-organic framework (MOF), [Cu(p-IPhHIDC)]n (1) (p-IPhH3 IDC=2-(p-N-imidazol-1-yl)-phenyl-1 H-imidazole-4,5-dicarboxylic acid) as an advanced ammonia impedance sensor at room temperature and 68-98 % relative humidity (RH). MOF 1 shows the optimized proton conductivity value of 1.51×10-3  S cm-1 at 100 °C and 98 % RH. Its temperature-dependent and humidity-dependent proton conduction properties have been explored. The large amount of uncoordinated carboxylate groups between the layers plays a vital role in the resultant conductivity. Distinctly, the fabricated MOF-based sensor displays the required stability toward NH3 , enhanced sensitivity, and notable selectivity for NH3 gas. At room temperature and 68 % RH, it gives a remarkable gas response of 8620 % to 130 ppm NH3 gas and lower detection limit of 2 ppm towards NH3 gas. It is also found that the gas response of the ammonia sensor increases linearly with the increase of NH3 gas concentration under 68-98 % RH and room temperature. Moreover, the sensor indicates excellent reversibility and selectivity toward NH3 versus N2 , H2 , O2 , CO, CO2 , benzene, and MeOH. Based on structural analyses, activation energy calculations, water and NH3 vapor absorptions, and PXRD determinations, proton conduction and NH3 sensing mechanisms are suggested.

Alkylated branched poly(ß-amino esters) demonstrate strong DNA encapsulation, high nanoparticle stability and robust gene transfection efficacy.

A branched poly(ß-amino ester) with numerous alkyl chains (BPA) is designed and synthesized as a safe and efficient non-viral vector. The branching and hydrophobicity synergistically endow BPA with tight DNA condensation, high polyplex stability in serum, high cellular uptake and ultimately robust gene transfection efficiency, largely superior to its linear counterpart (LPA). Our results demonstrate that branching matters for gene delivery by hydrophobic gene vectors.