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Certain proteins and synthetic covalent polymers experience aqueous phase transitions, driving functional self-assembly. Herein, we unveil the ability of supramolecular polymers (SPs) formed by G4.Cu+ to undergo heating-induced unexpected aqueous phase transitions. For the first time, guided by Cu+, guanosine (G) formed a highly stable G-quartet (G4.Cu+)/G-quadruplex as a non-canonical DNA secondary structure with temperature tolerance, distinct from the well-known G4.K+. The G4.Cu+ self-assembled in water through p-p stacking, metallophilic and hydrophobic interactions, forming thermally robust SPs. This enhanced stability is attributed to the stronger coordination of Cu+ to four carbonyl oxygens of G-quartet and the presence of Cu+---Cu+ attractive metallophilic interactions in Cu+-induced G-quadruplex, exhibiting a significantly higher interaction energy than K+ as determined computationally. Remarkably, the aqueous SP solution exhibited heating-induced phase transitions-forming a hydrogel through dehydration-driven crosslinking of SPs below cloud temperature (Tcp) and a hydrophobic collapse-induced solid precipitate above Tcp, showcasing a lower critical solution temperature (LCST) behavior. Notably, this LCST behavior of G4.Cu+ SP originates from biomolecular functionality rather than commonly exploited thermo-responsive oligoethylene glycols with supramolecular assemblies. Furthermore, exploiting the redox reversibility of Cu+/Cu2+, we demonstrated control over the assembly and disassembly of G-quartets/G-quadruplex and gelation reversibly., (© 2025 Wiley‐VCH GmbH.)

Introducing kosmotropic salts enhances protein stability and reduces solubility by withdrawing water from the protein surface, leading to 'salting out', a phenomenon we have mimicked in supramolecular polymers (SPs). Under the guidance of Ag + , folic acid (FA) self-assembled in water through slipped-stacking and hydrophobic interactions into elongated, robust one-dimensional SPs, resulting in thermo-stable supergels. The SPs exhibited temperature and dilution tolerance, attributed to the stability of the FA-Ag + complex and its hydrophobic stacking. Importantly, FA-Ag + SP's stability has been augmented by the kosmotropic anions, such as SO 4 2- , strengthening hydrophobic interactions in the SP, evident from the enhanced J-band, causing improvement of gel's mechanical property. Interestingly, higher kosmotrope concentrations caused a significant decrease in SP's solubility, leading to precipitation of the reinforced SPs─a 'salting out' effect. Conversely, chaotropes like ClO 4 - slightly destabilized hydrophobic stacking and promoted an extended conformation of individual SP chain with enhanced solubility, resembling a 'salting in' effect.

Background: Subacute subdural hematoma (SASDH) is an entity which is yet to capture the popular imagination among the neurosurgeons. Its management is often equated clinically to that of the chronic subdural hematoma (CSDH). However, their neurological deterioration is usually rapid, which seems to align them with acute subdural hematoma (ASDH). We proceed for their epidemiological evaluation. The advantages of a novel "double barrel technique (DbT)" over the conventional burrhole drainage are also presented., Methods: This retrospective study was conducted on all the patients having clinical and radiological evidence of SASDH, admitted to a tertiary care referral institute, during the period August 2013 to December 2015. Postoperatively, patients were followed-up for 3-24 months., Results: 46.87% of the patients belonged to the 35-54 year age group with a male predominance (3.6:1); 68.7% had a history of alcohol abuse, whereas aspirin users were 25%. 87.5% cases were unilateral, 18.75% were hemispheric, and 46.87% were present on the left side. Altered consciousness (100%) followed by headache (37.5%) were the most common presenting clinical features., Conclusion: SASDH is an uncommon neurosurgical entity (0.89% of traumatic brain injury cases in our study) and mimics both CSDH as well as ASDH. The true incidence of SASDH may have been underestimated due to its clinical imitation with CSDH. This study in a South Asian nation also provides the epidemiological data of this rare neurosurgical entity. Outcome of surgery is good; our retrospective study confirms that "DbT" is an adequate and safe treatment. However, a better designed, randomized control trial will be needed to reinforce our findings.

Background: Isolated orbital neurofibroma unassociated with systemic neurofibromatosis is relatively rare and may be difficult to clinically differentiate from other orbital tumors. Sensory branches of the trigeminal nerve-namely lacrimal, nasociliary, and frontal-are the most common nerves of origin for intraorbital neurofibroma, but we discovered a neurofibroma arising out of the right trochlear nerve, in absence of clinical stigmata of neurofibromatosis type 1, which is rare., Case Description: A 41-year-old adult presented with painless progressive proptosis of the right eye for 10 years without history of visual problems or diplopia. The right eye had axial proptosis with periorbital swelling. On magnetic resonance imaging (MRI), a right orbital extraconal, expansile, lobulated, cystic space-occupying lesion was seen with an enhancing component, pushing the lateral rectus with T1 isointensity and T2 hyperintensity, suggesting a preoperative working diagnosis of pseudotumor or lymphoproliferative tumor. Intraoperatively, a rudimentary slender, white, elongated structure was passing through the length of the tumor. The elongated tumor engulfing the trochlear nerve was traced up to the lateral part of the superior orbital fissure. The tumor was excised completely and was found to be a neurofibroma., Conclusion: Isolated trochlear nerve neurofibromas, in the absence of clinical stigmata of NF1, are rare. Multiplicity, multilobulation, ring-configured contrast enhancement, and heterogenous MRI signal intensities help in the accurate preoperative imaging diagnosis. A possible cure is thus achievable with complete excision without damaging important adjacent neurovasculo-musculotendinous structures in the orbit. To the best of our knowledge, this is the fourth reported case of isolated trochlear nerve neurofibroma., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Cerebral aspergillosis, often encountered in immunocompromised patients, is almost always fatal despite radical surgical and medical management and frequently is a finding at autopsy. Attempts at fungal isolation often are unsuccessful, and a high index of radiologic suspicion is necessary., Case Description: A premature, 5-month-old female infant, born via normal vaginal delivery, presented with a progressive increase in head size since birth, delayed developmental milestones, and intermittent vomiting for 1 month. There was no history of trauma and no evidence of diabetes mellitus or hypertension, family history of tuberculosis, gestational diabetes, jaundice, or febrile eruptions. Neonatal jaundice was present after day 1, remained for 2 days, and was treated with phototherapy. Findings of the general and systemic examinations were unremarkable. Findings of a neurologic examination revealed a hypoactive infant with papilledema and extensor plantar bilaterally. Computed tomography scan of brain showed hydrocephalus attributable to aqueductal stenosis. On endoscopic third ventriculostomy, dense, friable, whitish yellow, nonvascular masses were encountered in the third ventricle, obstructing it. Her endoscopic third ventriculostomy success score was 10 + 0 + 10 = 20%. Histopathologic examination and culture revealed Aspergillus flavus. A week later, a medium-pressure ventriculoperitoneal shunt was done, and voriconazole was added., Results: At discharge on the 7th postoperative day, 4 weeks and 12 weeks later (ie, first and second follow-up) the child was active, playful, and feeding normally. The first reported case of an aqueductal stenosis due to aspergillosis was in 2000 by van Landeghem FK et al. (Clin Neuropathol 19:26-29, 2000). To the best of our knowledge, this may only be the second reported case of hydrocephalus attributable to aqueductal stenosis caused by Aspergillosis. In conclusion, aspergillosis should not be ruled out as a differential diagnosis in aqueductal stenosis, even when the patient seems to be immunocompetent., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: Spinal cord compression can be due to various causes but spinal intramedullary tuberculoma is a rare cause. We report a case that had an intramedullary spinal cord tuberculomas in which the diagnosis was made histologically, without evidence of symptoms of systemic tuberculosis. This lesion, located in the thoracic region, mimicked as an intramedullary tumor radiologically., Case Description: The patient was a 25-year-old male who presented with a history of progressive paraparesis. Initial diagnosis was made as an intramedullary tumor by magnetic resonance imaging (MRI). The treatment of the patient involved is complete surgical excision of intramedullary lesion followed by appropriate antituberculous therapy. Postoperatively, his neurological symptoms were dramatically improved. With combination of both surgical and medical treatments, excellent clinical outcome was obtained., Conclusion: This case illustrates the risk of misdiagnosis and the importance of histological confirmation of a pathological lesion as spinal cord tuberculoma prior to surgical therapy, which should be kept in mind as a differential diagnosis of the intramedullary spinal cord tumors.