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PURPOSE: Invasive cerebral aspergillosis (ICA) is a rare but fatal infection affecting neutropenic immunocompromised patients. Recently cases have been reported in non-neutropenic settings also. We hereby present a series of ICA cases in non-neutropenic patients diagnosed at our tertiary care centre in Western India between March to October 2021. METHODS: All patients with clinico-radiological suspicion of CNS infections were analysed. Data regarding Clinico-radiological features, diagnosis, treatment and outcome were collected. After ruling out bacterial, viral and mycobacterial causes, appropriate samples were sent for KOH (potassium hydroxide) wet mount, fungal culture, histopathology and serum/CSF galactomannan. RESULTS: A total of four patients were diagnosed with ICA with a mean age of 43.5 years. Three patients had significant comorbidities; Diabetes mellitus, chronic liver disease and COVID-19 pneumonia treated with dexamethasone, respectively. One patient had no known predisposing factor. Radiologically, one patient presented with a frontal brain abscess and two patients had multiple subcortical hyperintensities. Three patients were diagnosed based on CSF galactomannan (Platelia™ Aspergillus antigen, Bio-Rad, France) with OD >1 and one patient had high serum galactomannan (OD >2). CSF culture grew Aspergillus species in two patients. All patients were treated with Voriconazole. One patient recovered, and the remaining three succumbed due to delayed presentation and extensive cerebral involvement. CONCLUSION: Even in non-neutropenic patients, a high index of suspicion is warranted for cerebral aspergillosis. CSF galactomannan can be considered a reliable marker for diagnosing ICA in non-neutropenic settings. Early diagnosis allows timely antifungal therapy, which could be a key to improving the outcomes.
Assuntos
Aspergilose , COVID-19 , Humanos , Adulto , Aspergilose/diagnóstico , Aspergilose/tratamento farmacológico , Aspergillus , Voriconazol/uso terapêutico , França , Mananas , GalactoseRESUMO
Patients with seizures represent a challenging clinical population both in pediatrics and adults. Accurate diagnosis of the cause of a seizure is important in choosing an effective treatment modality, surgical planning, predicting a prognosis, and follow-up. Magnetic resonance (MR) imaging using a dedicated epilepsy protocol plays a key role in the workup of these patients. Additional MR techniques such as T2 relaxometry and MR spectroscopy show a promising role to arrive at a final diagnosis. The spectrum of epileptogenic causes is broad. Radiologists and physicians need to be updated and require a patterned approach in light of clinical history and electroencephalogram findings to arrive at a reasonable differential diagnosis. This pictorial essay aims to review a few of the common and uncommon causes of seizures and their imaging features.
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Heavy metal removal from water resources is essential for environmental protection and the production of safe drinking water. In this direction, Zinc doped Aluminium Oxide (Zn:Al2O3) nanoparticles were incorporated into Polysulfone (PSf) to prepare mixed matrix membranes for the efficient removal of heavy metals from water. These Zn:Al2O3 nanoparticles prepared by the solution combustion method have a very high surface area (261.44 m2/g) with an approximate size of 50 nm. X-ray Photoelectron Spectroscopy analysis showed that the Al and Zn were in +3 and + 2 oxidation states, respectively. Cross-sectional Scanning Electron Microscopy images revealed the finger-like morphology and porous nature of the membranes. In this study, the optimum loading amount of Zn:Al2O3 nanoparticles was determined. Synthesized membranes showed enhanced hydrophilicity, surface charge, and porosity, which enabled the removal of arsenic and lead with efficiencies of 87% and 98%, respectively. A study of the antifouling properties carried out at various pressures with a feed solution containing Bovine Serum Albumin (BSA) showed 98.4% of flux recovery ratio and reusability up to three continuous cycles. Moreover, this work demonstrates a rational design of novel mixed matrix membranes exhibiting characteristics of hydrophilicity, surface charge, and porosity adequate to realize the efficient removal of heavy metals.
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Metais Pesados , Zinco , Óxido de Alumínio , Estudos Transversais , Membranas Artificiais , Polímeros , SulfonasRESUMO
Producing pure H2 and O2 to sustain the renewable energy sources with minimal environmental damage is a key objective of photo/electrochemical water-splitting research. Metallic Ni-based electrocatalysts are expensive and eco-hazardous. This has rendered the replacement or reduction of Ni content in Ni-based electrocatalysts a decisive criterion in the development of bifunctional electrocatalytic materials. In the current study, spinel/ilmenite composite nickel titanate (NTO) nanofibers were synthesised using sol-gel assisted electrospinning followed by pyrolysis at different soaking temperatures (viz., 773, 973, and 1173 K). The presence of a defective spinel NTO phase (SNTO) distributed uniformly along the nanofibers was confirmed by X-ray photoelectron and Raman spectroscopy. The electron micrographs revealed the morphological change of NTO nanofibers from a mosaic to bamboo structure with an increase in pyrolysis soaking temperature. The electrocatalytic activity of NTO nanofibers obtained at different pyrolysis soaking temperatures for alkaline water-splitting was studied. The highly defective SNTO manifests properties similar to metallic Ni and favours H2 evolution through the hydrogen evolution reaction (HER) by adsorbing more H+ ions on active sites. In contrast, the ilmenite NTO favours O2 discharge. These results are explained based on the morphology of the NTO nanofibers. The mosaic structure which has higher porosity and greater SNTO content shows excellent HER performance. In contrast, the large bamboo structured NTO nanofibers which have lesser porosity and SNTO content cage the bigger (OH)ads ions at their catalytic sites to facilitate OER performance.
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The crystal structures of (E)-N'-(2-chloro-benzyl-idene)-4-nitro-benzene-sulfono-hydrazide, C13H10ClN3O4S (I), (E)-N'-(2-methyl-benzyl-idene)-4-nitro-benzene-sulfono-hydrazide, C14H13N3O4S (II), and (E)-N'-(4-methyl-benzyl-idene)-4-nitro-benzene-sulfono-hydrazide monohydrate, C14H13N3O4S·H2O (III), have been synthesized, characterized and their crystal structures determined to study the effects of the nature and sites of substitutions on the structural parameters and the hydrogen-bonding inter-actions. All three compounds crystallize in the monoclinic crystal system, with space group P21 for (I) and P21/c for (II) and (III). Compound (III) crystallizes as a monohydrate. All three compounds adopt an E configuration around the C=N bond. The mol-ecules are bent at the S atom with C-S-N-N torsion angles of -59.0â (3), 58.0â (2) and -70.2â (1)° in (I), (II) and (III), respectively. The sulfono-hydrazide parts are also non-linear, as is evident from the S-N-N-C torsional angles of 159.3â (3), -164.2â (1) and 152.3â (1)° in (I), (II) and (III), respectively, while the hydrazide parts are almost planar with the N-N=C-C torsion angles being -179.1â (3)° in (I), 176.7â (2)° in (II) and 175.0â (2)° in (III). The 4-nitro-substituted phenyl-sulfonyl and 2/4-substituted benzyl-idene rings are inclined to each other by 81.1â (1)° in (I), 81.4â (1)° in (II) and 74.4â (1)° in (III). The compounds show differences in hydrogen-bonding inter-actions. In the crystal of (I), mol-ecules are linked via N-Hâ¯O hydrogen bonds, forming C(4) chains along the a-axis direction that are inter-connected by weak C-Hâ¯O hydrogen bonds, generating layers parallel to the ac plane. In the crystal of (II), the amino H atom shows bifurcated N-Hâ¯O(O) hydrogen bonding with both O atoms of the nitro group generating C(9) chains along the b-axis direction. The chains are linked by weak C-Hâ¯O hydrogen bonds, forming a three-dimensional framework. In the crystal of (III), mol-ecules are linked by Ow-Hâ¯O, N-Hâ¯Ow and C-Hâ¯O hydrogen bonds, forming layers lying parallel to the bc plane. The fingerprint plots generated for the three compounds show that for (I) and (II) the Oâ¯H/Hâ¯O contacts make the largest contributions, while for the para-substituted compound (III), Hâ¯H contacts are the major contributors to the Hirshfeld surfaces.
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Two (E)-N'-(p-substituted benzyl-idene)-4-chloro-benzene-sulfono-hydrazides, namely, (E)-4-chloro-N'-(4-chloro-benzyl-idene)benzene-sulfono-hydrazide, C13H10Cl2N2O2S, (I), and (E)-4-chloro-N'-(4-nitro-benzyl-idene)benzene-sulfono-hydrazide, C13H10ClN3O4S, (II), have been synthesized, characterized and their crystal structures studied to explore the effect of the nature of substituents on the structural parameters. Compound (II) crystallized with two independent mol-ecules [(IIA) and IIB)] in the asymmetric unit. In both compounds, the configuration around the C=N bond is E. The mol-ecules are twisted at the S atom with C-S-N-N torsion angles of -62.4â (2)° in (I), and -46.8â (2)° and 56.8â (2)° in the mol-ecules A and B of (II). The 4-chloro-phenyl-sulfonyl and 4-substituted benzyl-idene rings form dihedral angles of 81.0â (1)° in (I), 75.9â (1)° in (IIA) and 73.4â (1)° in (IIB). In the crystal of (I), mol-ecules are linked via pairs of N-Hâ¯O hydrogen bonds, forming inversion dimers with an R 2 2(8) ring motif. The dimers are linked by C-Clâ¯π inter-actions, forming a three-dimensional structure. In the crystal of (II), mol-ecules are linked by C-Hâ¯π inter-actions and N-Hâ¯O hydrogen bonds, forming -A-B-A-B- chains along the c-axis direction. The chains are linked via C-Hâ¯O and C-Hâ¯π inter-actions, forming layers parallel to the bc plane. Two-dimensional fingerprint plots show that the most significant contacts contributing to the Hirshfeld surface for (I) are Hâ¯H contacts (26.6%), followed by Clâ¯H/Hâ¯Cl (21.3%), Oâ¯H/Hâ¯O (15.5%) and Clâ¯C/Câ¯Cl (10.7%), while for (II) the Oâ¯H/Hâ¯O contacts are dominant, with a contribution of 34.8%, followed by Hâ¯H (15.2%), Câ¯H/Hâ¯C (14.0%) and Clâ¯H/Hâ¯Cl (10.0%) contacts.
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(E)-N'-Benzyl-idene-4-chloro-benzene-sulfono-hydrazide, C13H11ClN2O2S, (I), and its ortho- and para-methyl-substituted derivatives, C14H13ClN2O2S, namely (E)-4-chloro-N'-(2-methyl-benzyl-idene)benzene-sulfono-hydrazide, (II), and (E)-4-chloro-N'-(4-methyl-benzyl-idene)benzene-sulfono-hydrazide, (III), have been synthesized, characterized spectroscopically and their crystal structures determined to investigate the effect of the substitution site of the benzyl-idene group on the structural and supra-molecular features in these compounds. Compounds (I) and (II) are isotypic while compound (III) is different. All three mol-ecules are bent at the S atom with C-S-N-N torsion angles of -66.0â (3), -66.0â (3) and -58.4â (2)° for (I), (II) and (III), respectively. The hydrazone portions of the mol-ecules, S-N-N=C, are slightly twisted from planarity, with a torsion angle of 166.5â (3)° in (I), 165.4â (3)° in (II) and 157.9â (2)° in (III). The two aromatic rings present in the compounds are inclined to each other by 78.4â (2), 74.8â (2) and 76.9â (1)° in (I), (II) and (III), respectively. In the crystal structure of the parent compound (I), and of the ortho-methyl derivative (II), an N-Hâ¯O hydrogen bond links the mol-ecules into chains along [001], which are inter-connected by weak inter-molecular C-Hâ¯O inter-actions, generating layers lying parallel to the bc plane. In the crystal of the para derivative (III), however, the packing is significantly different. Here mol-ecules are linked by pairs of N-Hâ¯O hydrogen bonds, forming inversion dimers with an R 2 2(8) ring motif. The dimers are then linked by C-Clâ¯π inter-actions, forming ribbons propagating along [10]. Hirshfeld surface analyses show that the van der Waals inter-actions constitute the major contribution to the inter-molecular inter-actions in the crystal structures of all three compounds. The fingerprint plots indicate that the Hâ¯H contacts make the largest contributions to the Hirshfeld surfaces.
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The asymmetric unit of the title compound, C17H16N4O6, contains two independent mol-ecules (A and B). The two benzene rings are twisted by an angle of 79.14â (7)° in mol-ecule A, whereas, in mol-ecule B, they are inclined by 19.02â (14)°. The conformations of the mol-ecules are stabilized by intra-molecular N-Hâ¯O hydrogen bonds between the amide nitro-gen atom and the O atom of the ortho-nitro substituent on the phenyl ring, enclosing an S(6) ring motif. In the amide and aliphatic segments, all the N-H, C=O and C-H bonds are anti to each other. In the crystal, the A and B mol-ecules are linked by inter-molecular amide-to-amide N-Hâ¯O hydrogen bonds, resulting in chains running along the b-axis direction. The inter-molecular inter-actions were analysed using Hirshfeld surface analysis. The two-dimensional fingerprint plots of the inter-molecular contacts indicate that the major contributions are from Hâ¯H and Oâ¯H inter-actions.