Electrochemical reduction of NO catalyzed by boron-doped C60 fullerene: a first-principles study

The electrochemical reduction of nitrogen monoxide (NO) is one of the most promising approaches for converting this harmful gas into useful chemicals. Using density functional theory calculations, the work examines the potential of a single B atom doped C₆₀ fullerene (C₅₉B) for catalytic reduction of NO molecules. The results demonstrate that the NO may be strongly activated over the B atom of C₅₉B, and that the subsequent reduction process can result in the formation of NH₃ and N₂O molecules at low and high coverages, respectively. Based on the Gibbs free energy diagram, it is inferred that the C₅₉B has excellent catalytic activity for NO reduction at ambient conditions with no potential-limiting. At normal temperature, the efficient interaction between the *NOH and NO species might lead to the spontaneous formation of the N₂O molecule. Thus, the findings of this study provide new insights into NO electrochemical reduction on heteroatom doped fullerenes, as well as a unique strategy for fabricating low-cost NO reduction electrocatalysts with high efficiency.

Using DFT calculations, the potential of B-doped C₆₀ fullerene is evaluated for electrochemical reduction of nitrogen monoxide. The B-doped C₆₀ exhibits exceptional catalytic activity and high selectivity for reduction of nitrogen monoxide.     

A case report of a Cerebellopontine angle lipoma revealed by vertigo

Cerebellopontine angle (CPA) lipoma is an extremely rare lesion representing only 0.1% of all the CPA tumors. We present a case of a 56‐year‐old woman with a 6‐month history of vertigo. Cerebral MRI showed a left CPA lipoma. The patient was managed conservatively.     

Neurosyphilis presenting with focal middle cerebral artery stenosis and acute ischemic stroke: A case report

Despite widespread screening and active management of syphilis infection, the rate of secondary and tertiary syphilis has increased over the past decade in the United States, especially with human immunodeficiency virus co-infection. We report a case of ischemic strokes in the middle cerebral artery (MCA) territory with focal stenosis of the left M1 segment of the MCA resulting from neurosyphilis with manifestation of subacute intermittent right-sided hemi-body numbness and transient word finding difficulties in a young adult with no prior known history of syphilis or significant cerebrovascular risk factors. A diagnostic cerebral angiogram was done which was initially concerning for possibility of reversible cerebral vasoconstriction syndrome (RCVS). The serum Treponema pallidum RPR testing resulted positive (1:32 titer) as well as subsequent reactive cerebrospinal fluid (CSF) VDRL test (ratio, 1:8). The patient was treated with intravenous ceftriaxone as well as verapamil and recovered without any residual deficits. To the best of our knowledge, this is the first reported evidence of possible RCVS in a case of neurosyphilis and related ischemic stroke. This case underscores the importance of evaluation for syphilis in young patients with fewer known vascular risk factors, who present with an ischemic stroke. Given the higher rates of stroke recurrence in neurosyphilis relative to few other stroke risk factors, early diagnosis, and treatment is furthermore essential to prevent disease progression.     

Spontaneous rapid regression of a juvenile primary aneurysmal bone cyst of the skull: A case report and literature review

Aneurysmal bone cyst (ABC) is a benign lesion that often starts off the metaphysis of long bones and which, as it grows, may blow out bone. Only 3%-6% of cases are located in the skull. Spontaneous recovery has been reported. These cases occur more often in adults and in pelvic locations. Spontaneous regression at the skull level remains a very rare entity and few cases were described in the literature. Here, the authors report another case of spontaneous rapid regression of ABC of the skull in a 7-year-old boy revealed by gradually increasing painless hard swelling in the right frontal bone region with rapid spontaneous regression within 15 days. The authors will also proceed with an overview concerning this rare entity.     

Expression of claudin‐11 by tumor cells in cutaneous squamous cell carcinoma is dependent on the activity of p38δ

The incidence of cutaneous squamous cell carcinoma (cSCC) is rapidly increasing, and the prognosis of patients with metastatic disease is poor. There is an emerging need to identify molecular markers for predicting aggressive behaviour of cSCC. Here, we have examined the role of tight junction (TJ) components in the progression of cSCC. The expression pattern of mRNAs for TJ components was determined with RNA sequencing and oligonucleotide array‐based expression analysis from cSCC cell lines (n=8) and normal human epidermal keratinocytes (NHEK, n=5). The expression of CLDN11 was specifically elevated in primary cSCC cell lines (n=5), but low or absent in metastatic cSCC cell lines (n=3) and NHEKs. Claudin‐11 was detected in cell‐cell contacts of primary cSCC cells in culture by indirect immunofluorescence analysis. Analysis of a large panel of tissue samples from sporadic UV‐induced cSCC (n=65), cSCC in situ (n=56), actinic keratoses (n=31), seborrhoeic keratoses (n=7) and normal skin (n=16) by immunohistochemistry showed specific staining for claudin‐11 in intercellular junctions of keratinizing tumor cells in well and moderately differentiated cSCCs, whereas no staining for claudin‐11 was detected in poorly differentiated tumors. The expression of claudin‐11 in cSCC cells was dependent on the activity of p38δ MAPK and knock‐down of claudin‐11 enhanced cSCC cell invasion. These findings provide evidence for the role of claudin‐11 in regulation of cSCC invasion and suggest loss of claudin‐11 expression in tumor cells as a biomarker for advanced stage of cSCC.