Bifunctional Metal-Organic Nanoballs Featuring Lewis Acidic and Basic Sites as a New Platform for One-Pot Tandem Catalysis.

The design and synthesis of polyhedra using coordination-driven self-assembly has been an intriguing research area for synthetic chemists. Metal-organic polyhedra are a class of intricate molecular architectures that have garnered significant attention in the literature due to their diverse structures and potential applications. Hereby, we report Cu-MOP, a bifunctional metal-organic cuboctahedra built using 2,6-dimethylpyridine-3,5-dicarboxylic acid and copper acetate at room temperature. The presence of both Lewis basic pyridine groups and Lewis acidic copper sites imparts catalytic activity to Cu-MOP for the tandem one-pot deacetalization-Knoevenagel/Henry reactions. The effect of solvent system and time duration on the yields of the reactions was studied, and the results illustrate the promising potential of these metal-organic cuboctahedra, also known as nanoballs for applications in catalysis.

Detoxification of areca nut acid hydrolysate and production of xylitol by Candida tropicalis (MTCC 6192).

Areca nut husk is the most promising alternative source of low-cost raw materials because it contains a considerable amount of five-carbon monosaccharide sugar in the form of xylose. This polymeric sugar can be isolated and transformed into a value-added chemical using fermentation. To extract sugars from areca nut husk fibers, preliminary pretreatment, such as dilute acid hydrolysis (H2SO4), was performed. The hemicellulosic hydrolysate of areca nut husk can produce xylitol through fermentation, but toxic components inhibit the growth of microorganisms. To overcome this, a series of detoxification treatments, including pH adjustment, activated charcoal, and ion exchange resin, were carried out to reduce the concentration of inhibitors in the hydrolysate. This study reports a remarkable 99% removal of inhibitors in the hemicellulosic hydrolysate. Subsequently, a fermentation process using Candida tropicalis (MTCC6192) was executed with the detoxified hemicellulosic hydrolysate of areca nut husk, yielding an optimum xylitol yield of 0.66 g/g. This study concludes that detoxification techniques like pH adjustment, activated charcoal, and ion exchange resins are the most economical and effective methods for eliminating toxic compounds in hemicellulosic hydrolysates. Therefore, the medium derived after detoxification from areca nut hydrolysate may be considered to have significant potential for xylitol production.

Large-Scale Synthesis of Covalent Organic Frameworks: Challenges and Opportunities.

Connecting organic building blocks by covalent bonds to design porous crystalline networks has led to covalent organic frameworks (COFs), consequently transferring the flexibility of dynamic linkages from discrete architectures to extended structures. By virtue of the library of organic building blocks and the diversity of dynamic linkages and topologies, COFs have emerged as a novel field of organic materials that propose a platform for tailor-made complex structural design. Progress over the past two decades in the design, synthesis, and functional exploration of COFs in diverse applications successively established these frameworks in materials chemistry. The large-scale synthesis of COFs with uniform structures and properties is of profound importance for commercialization and industrial applications; however, this is in its infancy at present. An innovative designing and synthetic approaches have paved novel ways to address future hurdles. This review article highlights the fundamental of COFs, including designing principles, coupling reactions, topologies, structural diversity, synthetic strategies, characterization, growth mechanism, and activation aspects of COFs. Finally, the major challenges and future trends for large-scale COF fabrication are outlined.

Xylitol Production by Candida tropicalis from Areca Nut Husk Enzymatic Hydrolysate and Crystallization.

Lignocellulosic biomasses are extensively used by researchers to produce a variety of renewable bioproducts. This research described an environment-friendly technique of xylitol production by an adapted strain of Candida tropicalis from areca nut hemicellulosic hydrolysate, produced through enzymatic hydrolysis. To enhance the activity of xylanase enzymes, lime and acid pretreatment was conducted to make biomass more amenable for saccharification. To improve the efficiency of enzymatic hydrolysis, saccharification parameters like xylanase enzyme loading were varied. Results exposed that the highest yield (g/g) of reducing sugar, about 90%, 83%, and 15%, were achieved for acid-treated husk (ATH), lime-treated husk (LTH), and raw husk (RH) at an enzyme loading of 15.0 IU/g. Hydrolysis was conducted at a substrate loading of 2% (w/V) at 30 °C, 100 rpm agitation, for 12 h hydrolysis time at pH 4.5 to 5.0. Subsequently, fermentation of xylose-rich hemicellulose hydrolysate was conducted with pentose utilizing the yeast Candida tropicalis to produce xylitol. The optimum concentration of xylitol was obtained at about 2.47 g/L, 3.83 g/L, and 5.88 g/L, with yields of approximately 71.02%, 76.78%, and 79.68% for raw fermentative hydrolysate (RFH), acid-treated fermentative hydrolysate (ATFH), and lime-treated fermentative gydrolysate (LTFH), respectively. Purification and crystallization were also conducted to separate xylitol crystals, followed by characterization like X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. Results obtained from crystallization were auspicious, and about 85% pure xylitol crystal was obtained.

Clinical characteristics, treatment outcomes and factors associated with severe illness in 813 COVID-19 patients admitted in a tertiary care hospital of eastern India.

INTRODUCTION: This retrospective observational study has been designed to identify clinical characteristics, treatment outcomes and factors associated with severe illness in 813 COVID-19 patients hospitalised in an Indian tertiary care hospital. MATERIAL AND METHODS: This was a retrospective analysis of patient admitted between 1st July to 15th Aug 2020 with COVID-19 infections. Logistic regression was performed to explore the association of clinical characteristics and laboratory parameters with the risk of severe disease and mortality. The statistical significance level was set at 0.05 (two-tailed). RESULTS: Out of 813 study patients, 630 (77.50%) patients were categorised with mild to moderate while 183 (22.50%) patients as severe Covid infection. Mortality was significantly higher in severe Covid patients as compared to mild moderate cases (66.21% vs. 10.31%. p<0.0001. Patients with severe infection were significantly more likely to have diabetes hypertension, chronic kidney disease (CKD) and had significantly higher Neutrophil count, serum creatinine, C-reactive protein (CRP), ferritin, D-Dimer and decreased haemoglobin, lymphocyte and serum calcium than patients with mild-moderate infection. In Multivariate analy-sis, age more than 60 years [AOR: 2.114, 95% CI (1.05-4.254), 0.036], NLR more than 3.3 [AOR: 1.082, 95% CI (1.030-1.137), 0.002] and D-Dimer >1 µg/mL [AOR: 2.999 (1.464- 6.146),0.003] were found significantly associated with severe disease (p < 0.05). Factors associated with mortality were age more than 60 years, presence of breathlessness, severe disease or presence of chronic kidney disease. CONCLUSIONS: Factors like elderly age (age > 60 years), elevated NRL, CRP, D-Dimer and serum ferritin were associated with sig-nificantly higher risk to develop severe COVID-19 infections. Elderly, and patients with CKD were associated with worse outcome.

State-of-the-Art Mixed Matrix Membranes (MMMs).

The performance of most polymer membranes suffers from the trade-off relationship between permeability and selectivity [...].

Radiological Lung Sequelae of Severe COVID-19: A Retrospective Observational Study From a Dedicated COVID Centre of Eastern India.

BACKGROUND: The pulmonary sequelae of severe COVID-19 infection are yet to be fully defined. The authors undertook this study to find out the proportion of severe COVID-19 patients having fibrosis-like lung sequelae during a medium-term follow-up period. MATERIALS AND METHODS: This was a retrospective observational study from a dedicated COVID centre of Eastern India. Severe COVID-19 patients who had undergone chest computerized tomography (CT) during the acute phase of illness and at least one follow-up CT with a gap of minimum two months between the two scans were included in the study. RESULT: A total of 39 patients who had recovered from severe COVID-19 pneumonia and presented to the pulmonary medicine OPD in the months of July and August 2021 were included. Patients with pre-existing lung disease (n-4), mild to moderate (n-11), and due to unavailability of CT scan (n-2) were excluded. A total of 22 patients (thirteen males, nine females) were thus included for analysis. Follow-up scans were performed with a mean of 2.5 months after the onset of the disease. Out of 22 patients, only one patient's follow-up scan was normal. Predominant fibrotic-like features were present in six (27.2%) patients, though some evidence of fibrosis-like changes were seen in 20 out of 22 (90.9%) patients. The remaining 15 (68.2%) patients with abnormal scans had predominant non-fibrotic changes like ground-glass opacities (GGOs), consolidation, cavity, or nodule. The most common presenting symptoms at the follow-up examination were dyspnoea (81.8%), cough (54.1%) followed by fatigue in 40.9% of patients. CONCLUSION: This study concluded that most of the severe COVID-19 patients have some residual radiological findings during medium-term follow-up. Fibrotic-like lesions are present in almost all patients but most of them get resolved with time. True fibrotic features like honeycombing are rarely seen as residual lung sequelae.

Impact of COVID-19-associated Mucormycosis in Kidney Transplant Recipients: A Multicenter Cohort Study.

BACKGROUND: COVID-19-associated mucormycosis (CAM) is a recently emerging entity. There is a lack of reports of CAM in organ transplant recipients. METHODS: We conducted a multicenter (n = 18) retrospective research in India during November 2020 to July 2021. The purpose of this study was to explore the clinical spectrum, outcome and risk factors for mortality of CAM in kidney transplant recipients (KTRs). RESULTS: The incidence of CAM was 4.4% (61/1382 COVID-19-positive KTRs) with 26.2% mortality. The median age of the cohort was 45 (38-54) y. Twenty (32%) were not hospitalized and 14 (22.9%) were on room air during COVID-19. The proportion of postdischarge CAM was 59.1%, while concurrent CAM was reported in 40.9%. The presentation of CAM was 91.8% rhino-orbital-cerebral mucormycosis and 8.2% pulmonary with 19.6% and 100% mortality, respectively. In the univariable analysis, older age, obesity, difficulty of breathing, high-flow oxygen requirement, and delay in starting therapy were significantly associated with mortality. In the multivariable logistic regression analysis, patients requiring high-flow oxygen therapy [odds ratio (95% confidence interval) = 9.3 (1.6-51); P = 0.01] and obesity [odds ratio (95% confidence interval) = 5.2 (1-28); P = 0.05] was associated with mortality. The median follow-up of the study was 60 (35-60) d. CONCLUSIONS: We describe the largest case series of CAM in KTRs. Morality in pulmonary CAM is extremely high. Severe COVID-19 pose extra risk for the development of CAM and associated mortality. Our report will help in better understanding the conundrum and management of CAM.

Clinical Profile and Outcome of Haemodialysis in Patients With COVID-19 - A Single Centre Experience.

Introduction Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing COVID-19 disease is the third coronavirus to have emerged in the last 20 years. The COVID-19 infection causes more severe illness in patients with comorbid diseases, especially in patients with diabetes, hypertension and kidney failure. Methods This is a retrospective study using electronic records and laboratory data of adult patients hospitalised at All India Institute of Medical Sciences (AIIMS), Patna between May 1st, 2020 and March 31st, 2021, who were diagnosed with COVID-19 and needed haemodialysis. The demographic characteristics, co-morbidities, symptoms, clinical course, laboratory parameters, and treatments were recorded. The aim of this study is to evaluate the clinical profile and outcome of patients on hemodialysis with COVID-19 infection. Results The study included 261 COVID-19 patients who needed haemodialysis. The most common symptoms on admission were fever (72.8%), cough (64.3%) and dyspnoea (46.6%). The mean age was 58.4 +/-15 years. A total of 195 patients (74.7%) were male. The most common co-morbid condition was hypertension (85.1%) followed by diabetes (71.9%). A total of 118 (45.2) patients had acute on chronic kidney disease (CKD), 40 (15.3) were on maintenance haemodialysis (MHD) and 103 (39.5) were having acute kidney injury (AKI). Eight patients were renal transplant recipients. At presentation, 183 (70.1%) patients were having mild to moderately severe infection and 78 (29.9%) patients were having severe disease. A total of 213 patients required ICU admissions, 186 (75.3%) of whom required invasive ventilation. Overall mortality was 66% (172/261) and the rest were discharged. Conclusion The study suggests that COVID-19 disease has a significantly more severe course and poorer outcome in patients requiring haemodialysis.

Indium-Organic Framework with soc Topology as a Versatile Catalyst for Highly Efficient One-Pot Strecker Synthesis of α-aminonitriles.

An In(III) based metal-organic framework (MOF), In-pbpta, with soc topology was constructed from the trigonal prismatic [In3(µ3-O)(H2O)3(O2C-)6] secondary building unit (SBU) and a custom-designed tetratopic linker H4pbpta (pbpta = 4,4',4″,4‴-(1,4-phenylenbis(pyridine-4,2,6-triyl))-tetrabenzoic acid)). The obtained MOF shows a Brunauer-Emmett-Teller surface area of 1341 m2/g with a pore volume of 0.64 cm3/g, which is the highest among the scarcely reported In-soc-MOFs. The constructed MOF demonstrates excellent performance as a heterogeneous Lewis acid catalyst for highly efficient conversion in a one-pot multicomponent Strecker reaction for the preparation of α-aminonitriles under solvent-free conditions, which can be easy to separate and recycle without significant loss of activity for up to seven cycles. The computational modeling studies suggest the presence of the three substrates in close vicinity to the In-oxo cluster. The strong interactions of the aldehyde/ketone and the amine with the In-oxo cluster together with the readily available cyanide ion around the In-oxo cluster lead to high catalytic conversion within a short period of time for the MOF catalyst. Our work therefore lays a foundation to develop MOF as a new class of efficient heterogeneous catalyst for one-pot Strecker reaction.

Better Outcome of Coronavirus Disease 2019 Infection in Kidney Transplant Recipients: A Case Series from Eastern India.

The coronavirus disease 2019 (COVID-19) led to a global pandemic which is still unfolding. Little is known about the presentation, course of disease, treatment, and outcome in kidney transplant recipients. In this series, we describe nine such patients who presented with COVID-19. The mean age of the patients was 41.22 years. The mean duration of kidney transplantation was 63.22 months. The most common symptom was fever (9/9), followed by malaise (7/9), cough (5/9), dyspnea (4/9), diarrhea (2/9), and hemoptysis (2/9). Five patients developed acute kidney injury. Antiproliferative was stopped in all cases. Three patients needed hospitalization due to hypoxia while others were managed at home. We observed that majority of patients could be managed at home with isolation and self-monitoring. Even patents with moderate-to-severe disease were managed with oxygen supplement, low molecular weight heparin, and remdesivir. All patients recovered without any short-term sequelae in two months follow-up.

Post coronavirus disease-2019 vaccination Guillain-Barré syndrome.

Guillain-Barré syndrome (GBS) is an acute inflammatory demyelinating disorder of the peripheral nerve. Different variants of GBS can produce a wide array of symptoms among which motor weakness, areflexia without bladder-bowel involvement are commonly encountered. ChAdOx1 nCoV-19 is a recombinant Corona Virus Vaccine and it is incorporated into India's coronavirus disease-2019 (COVID-19) vaccination program. Few rare instances of serious neurological complications have been reported following COVID-19 vaccination. Our case received 2 dose of COVID-19 vaccine. After receiving 1st dose he had rapid onset of ascending paralysis without any sensory and bladder bowel involvement. He received Intra Venous Immuno Globulin and Injection prednisolone for 5 days. Following that his lower limb weakness resolved rapidly but there was no improvement in upper limb weakness. Nerve conduction study showed demyelinating etiology and along with clinical features, it was appeared to be a case of GBS. However, more evidence is needed before establishing the causal relationship between COVID-19 vaccines and GBS.

Single-Pore versus Dual-Pore Bipyridine-Based Covalent-Organic Frameworks: An Insight into the Heterogeneous Catalytic Activity for Selective CH Functionalization.

Exponential growth in the field of covalent-organic frameworks (COFs) is emanating from the direct correlation between designing principles and desired properties. The comparison of catalytic activity between single-pore and dual-pore COFs is of importance to establish structure-function relationship. Herein, the synthesis of imine-linked dual-pore [(BPyDC)]x % -ETTA COFs (x = 0%, 25%, 50%, 75%, 100%) with controllable bipyridine content is fulfilled by three-component condensation of 4,4',4″,4'″-(ethene-1,1,2,2-tetrayl)tetraaniline (ETTA), 4,4'-biphenyldialdehyde, and 2,2'-bipyridyl-5,5'-dialdehyde in different stoichiometric ratio. The strong coordination of bipyridine moieties of [(BPyDC)]x % -ETTA COFs with palladium imparts efficient catalytic active sites for selective functionalization of sp2 CH bond to CX (X = Br, Cl) or CO bonds in good yield. To broaden the scope of regioselective CH functionalization, a wide range of electronically and sterically substituted substrates under optimized catalytic condition are investigated. A comparison of the catalytic activity of palladium decorated dual-pore frameworks with single-pore imine-linked Pd(II) @ Py-2,2'-BPyDC framework  is undertaken. The finding of this work provides a sporadic example of chelation-assisted CH functionalization and disclosed an in-depth comparison of the relationship between superior catalytic activity and core properties of rationally designed imine linked frameworks.

PEG@ZIF-8/PVDF Nanocomposite Membrane for Efficient Pervaporation Desulfurization via a Layer-by-Layer Technology.

The desulfurization property of conventional mixed matrix membranes (MMMs) cannot meet the necessary demand due to particles aggregation and interface defects. Here, we put forward a layer-by-layer (LBL) approach to make a novel PEG@ZIF-8/poly(vinylidene difluoride)(PVDF) composite membrane for pervaporation desulfurization. In this way, a ZIF-8 layer is covered on the surface of the PVDF porous membrane via an in situ growth method. Then, a PEG layer is covered on the ZIF-8 layer by a casting method. Compared with pristine PEG membranes, the separation performance of the ZIF-8@PEG/PVDF nanocomposite membrane increased significantly. This can be attributed to the homogeneous ZIF-8 particle layer and better compatibility between the poly(ethylene glycol) (PEG) matrix and ZIF-8 particles. The membrane achieves a maximum total flux of 3.08 kg·m-2·h-1 at the third in situ growth cycles of ZIF-8 particles and a maximum sulfur enrichment factor of 7.6 at the sixth in situ growth cycles of ZIF-8 particles.

Improved Desulfurization Performance of Polyethyleneglycol Membrane by Incorporating Metal Organic Framework CuBTC.

In this paper, copper benzene-1,3,5-tricarboxylate (CuBTC) was incorporated into polyethylenglyol (PEG) to prepare a mixed matrix membrane (MMM) for pervaporation desulfurization. The characterization results showed that the prepared CuBTC particles had an ideal octahedral shape and micropores. The Cu2+ in CuBTC interacts with thiophene via π-complexation, thus enhancing the separation performance of the hybrid membranes. The effect of CuBTC content and the operating condition on the pervaporation performance of the MMMs was investigated. An optimal pervaporation separation performance was acquired with a permeation flux of 2.21 kg/(m2·h) and an enrichment factor of 8.79, which were increased by 100% and 39% compared with the pristine PEG membrane. Moreover, the CuBTC-filled PEG membrane showed a good stability in the long-term desulfurization under a high operating temperature of 75 °C for five days.

Pore surface engineering of covalent organic frameworks: structural diversity and applications.

Connecting molecular building blocks by covalent bonds to form extended crystalline structures has caused a sharp upsurge in the field of porous materials, especially covalent organic frameworks (COFs), thereby translating the accuracy, precision, and versatility of covalent chemistry from discrete molecules to two-dimensional and three-dimensional crystalline structures. COFs are crystalline porous frameworks prepared by a bottom-up approach from predesigned symmetric units with well-defined structural properties such as a high surface area, distinct pores, cavities, channels, thermal and chemical stability, structural flexibility and functional design. Due to the tedious and sometimes impossible introduction of certain functionalities into COFs via de novo synthesis, pore surface engineering through judicious functionalization with a range of substituents under ambient or harsh conditions using the principle of coordination chemistry, chemical conversion, and building block exchange is of profound importance. In this review, we aim to summarize dynamic covalent chemistry and framework linkage in the context of design features, different methods and perspectives of pore surface engineering along with their versatile roles in a plethora of applications such as biomedical, gas storage and separation, catalysis, sensing, energy storage and environmental remediation.

Locust bean gum and sodium alginate based interpenetrating polymeric network microbeads encapsulating Capecitabine: Improved pharmacokinetics, cytotoxicity &in vivo antitumor activity.

A combination of biopolymers sodium alginate and locust bean gum has been used to prepare an interpenetrating polymeric network of an anticancer drug Capecitabine by ionotropic gelation method. For the optimization 32 levels, a full factorial design was employed to examine the influence of independent factors, i.e. polymer ratio and cross-linker concentration on responses particle size and drug entrapment. The obtained optimized formulation was examined for solid-state characterization, swelling study, in vitro drug release, SRB study, oral toxicity study, in vivo pharmacokinetic and in vivo antitumor study. The results of all the studies performed were found suitable in extending the release of a short elimination half-life drug with improved bioavailability and suggesting it to be safe and effective for oral drug delivery in treating colon cancer.

Investigation of the Anticancer Activity of Coordination-Driven Self-AssembledTwo-Dimensional Ruthenium Metalla-Rectangle.

Coordination-driven self-assembly is an effective synthetic tool for the construction of spatially and electronically tunable supramolecular coordination complexes (SCCs), which are useful in various applications. Herein, we report the synthesis of a two-dimensional discrete metalla-rectangle [(η6-p-cymene)4Ru4(C6H2O4)2(2)2](CF3SO3)4 (3) by the reaction of a dinuclear half-sandwich ruthenium (II) complex [Ru2(η6-p-cymene)2(C6H2O4)Cl2] (1) and bis-pyridyl amide linker (2) in the presence of AgO3SCF3. This cationic ruthenium metalla-rectangle (3) has been isolated as its triflate salt and characterized by analytical techniques including elemental analysis, Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance spectroscopy (1H-NMR), carbon nuclear magnetic resonance spectroscopy (13C-NMR), 1H-1H correlation spectroscopy (COSY), 1H-1H nuclear Overhauser effect spectroscopy (NOESY), diffusion ordered spectroscopy (DOSY), and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS). Significantly, the 2D cationic ruthenium metalla-rectangle showed better anticancer activity towards three different cell lines (A549, Caki-1 and Lovo) as compared with the parent ruthenium complex (1) and the commercially used drug, cisplatin.