Emergent salvage of the vertebral artery with flow diverter pipeline stent following vessel laceration: Systematic literature review and illustrative case example.

Background: Iatrogenic injury to neck vasculature is a potentially life-threatening complication of spine surgery. We present an illustrative case describing the use of the Pipeline Embolization Device (PED) in the emergent reconstruction of the vertebral artery (VA) following vessel laceration. In addition, we document a systematic review concerning the use of the PED in acute to chronic iatrogenic injury of the internal carotid or VAs.

Dual CD47 and PD-L1 blockade elicits anti-tumor immunity by intratumoral CD8 T cells.

Objectives: Bispecific antibodies targeting CD47 and PD-L1 (CD47 × PD-L1 BisAb) demonstrate efficacy against a range of solid cancers. While dual blockade negates anti-CD47-mediated toxicity, the effect of combined innate and adaptive immune activation on protective tumor-resident CD8 T cells has yet to be fully elucidated.

Methods: CD8 T cell populations were tracked upon CD47 × PD-L1 BisAb treatment in an orthotopic model of murine breast cancer where anti-tumor immunity is mediated by CD8 T cells.

Investigating the applicability of the CYP102A1-decoy-molecule system to other members of the CYP102A subfamily.

Cytochrome P450 enzymes (CYPs) have attracted much promise as biocatalysts in a push for cleaner and more environmentally friendly catalytic systems. However, changing the substrate specificity of CYPs, such as CYP102A1, can be a challenging task, requiring laborious mutagenesis. An alternative approach is the use of decoy molecules that "trick" the enzyme into becoming active by impersonating the native substrate.

Changes in Pediatric Non-accidental Trauma Emergency Department Visits During and Following the COVID-19 Lockdown.

A level 1 pediatric trauma registry database was examined for all non-accidental trauma (NAT) emergency department visits between 2016 and 2021, and average injury severity score assigned to those patients with physical injuries over 2019-2021. There was a decline in NAT visits in 2020 (267) from prior years (343 visits average over 2016-2019), with subsequent increase in 2021 (548). Injury severity score increased (ISS) in 2020 (7.

A Compound I Mimic Reveals the Transient Active Species of a Cytochrome P450 Enzyme: Insight into the Stereoselectivity of P450-Catalysed Oxidations.

Catching the structure of cytochrome P450 enzymes in flagrante is crucial for the development of P450 biocatalysts, as most structures collected are found trapped in a precatalytic conformation. At the heart of P450 catalysis lies Cpd I, a short-lived, highly reactive intermediate, whose recalcitrant nature has thwarted most attempts at capturing catalytically relevant poses of P450s. We report the crystal structure of P450BM3 mimicking the state in the precise moment preceding epoxidation, which is in perfect agreement with the experimentally observed stereoselectivity.

Tetraphenylporphyrin Enters the Ring: First Example of a Complex between Highly Bulky Porphyrins and a Protein.

Tetraphenylporphyrin (TPP) is a symmetrically substituted synthetic porphyrin whose properties can be readily modified, providing it with significant advantages over naturally occurring porphyrins. Herein, we report the first example of a stable complex between a native biomolecule, the haemoprotein HasA, and TPP as well as its derivatives. The X-ray crystal structures of nine different HasA-TPP complexes were solved at high resolutions.

Designer Outer Membrane Protein Facilitates Uptake of Decoy Molecules into a Cytochrome P450BM3-Based Whole-Cell Biocatalyst.

We report an OmpF loop deletion mutant, which improves the cellular uptake of external additives into an Escherichia coli whole-cell biocatalyst. Through co-expression of the OmpF mutant with wild-type P450BM3 in the presence of decoy molecules, the yield of the whole-cell biotransformation of benzene could be considerably improved. Notably, with the decoy molecule C7AM-Pip-Phe the yield duodecupled from 5.

Enhanced - and enantioselective cyclopropanation of styrene catalysed by cytochrome P450BM3 using decoy molecules.

We report the enhanced cis- and enantioselective cyclopropanation of styrene catalysed by cytochrome P450BM3 in the presence of dummy substrates, i.e. decoy molecules.

Expanding the applicability of cytochrome P450s and other haemoproteins.

Cytochrome P450BM3 has long been regarded as a promising candidate for use as a biocatalyst, owing to its excellent efficiency for the hydroxylation of unactivated C-H bonds. However, because of its high substrate specificity, its possible applications have been severely limited. Consequently, various approaches have been proposed to overcome the enzyme's natural limitations, thereby expanding its substrate scope to encompass non-native substrates, evoking chemoselectivity, regioselectivity and stereoselectivity and enabling previously inaccessible chemical conversions.

Crystals in Minutes: Instant On-Site Microcrystallisation of Various Flavours of the CYP102A1 (P450BM3) Haem Domain.

Despite CYP102A1 (P450BM3) representing one of the most extensively researched metalloenzymes, crystallisation of its haem domain upon modification can be a challenge. Crystal structures are indispensable for the efficient structure-based design of P450BM3 as a biocatalyst. The abietane diterpenoid derivative N-abietoyl-l-tryptophan (AbiATrp) is an outstanding crystallisation accelerator for the wild-type P450BM3 haem domain, with visible crystals forming within 2 hours and diffracting to a near-atomic resolution of 1.

Lack of B Lymphocytes Enhances CD8 T Cell-Mediated Resistance against Respiratory Viral Infection but Compromises Memory Cell Formation.

Following a respiratory virus infection, CXCR3 CX3CR1 and CXCR3 CX3CR1 CD8 T cells localize to different compartments within the lung and play an important role in host resistance, but mechanisms governing their optimal generation are poorly defined. We serendipitously found that B cell-deficient (μMT) mice were highly resistant to lethal infection with a virulent poxvirus strain and that depletion of CD8 T cells rendered these mice susceptible to infection. B cells were not required for the expansion of virus-specific CD8 T cells, but a greater proportion of activated CD8 T cells acquired an effector-like CXCR3 CX3CR1 phenotype in the absence of B cells.

Hijacking the Heme Acquisition System of for the Delivery of Phthalocyanine as an Antimicrobial.

To survive in the iron-devoid environment of their host, pathogenic bacteria have devised multifarious cunning tactics such as evolving intricate heme transport systems to pirate extracellular heme. Yet, the potential of heme transport systems as antimicrobial targets has not been explored. Herein we developed a strategy to deliver antimicrobials by exploiting the extracellular heme acquisition system protein A (HasA) of .

Batf3-Dependent Dendritic Cells Promote Optimal CD8 T Cell Responses against Respiratory Poxvirus Infection.

Respiratory infection with vaccinia virus (VacV) elicits robust CD8 T cell responses that play an important role in host resistance. In the lung, VacV encounters multiple tissue-resident antigen-presenting cell (APC) populations, but which cell plays a dominant role in priming of virus-specific CD8 effector T cell responses remains poorly defined. We used Batf3 mice to investigate the impact of CD103 and CD8α dendritic cell (DC) deficiency on anti-VacV CD8 T cell responses.

Reconstitution of full-length P450BM3 with an artificial metal complex by utilising the transpeptidase Sortase A.

Haem substitution is an effective approach to tweak the function of haemoproteins. Herein, we report a facile haem substitution method for self-sufficient cytochrome P450BM3 (CYP102A1) from Bacillus megaterium utilising the transpeptidase Sortase A from Staphylococcus aureus. We successfully constructed Mn-substituted BM3 and investigated its catalytic activity.

Whole-Cell Biotransformation of Benzene to Phenol Catalysed by Intracellular Cytochrome P450BM3 Activated by External Additives.

An Escherichia coli whole-cell biocatalyst for the direct hydroxylation of benzene to phenol has been developed. By adding amino acid derivatives as decoy molecules to the culture medium, wild-type cytochrome P450BM3 (P450BM3) expressed in E.coli can be activated and non-native substrates hydroxylated, without supplementing with NADPH.

The TNF Superfamily Molecule LIGHT Promotes the Generation of Circulating and Lung-Resident Memory CD8 T Cells following an Acute Respiratory Virus Infection.

The transition of effector T cells or memory precursors into distinct long-lived memory T cell subsets is not well understood. Although many molecules made by APCs can contribute to clonal expansion and effector cell differentiation, it is not clear if clonal contraction and memory development is passive or active. Using respiratory virus infection, we found that CD8 T cells that cannot express the TNF family molecule lymphotoxin-like, exhibits nducible expression, competes with HSV lycoprotein D for herpes virus entry mediator, a receptor expressed by T lymphocytes (LIGHT) are unimpaired in their initial response and clonally expand to form effector cell pools.

Inflammatory monocytes contribute to the persistence of CXCR3 CX3CR1 circulating and lung-resident memory CD8 T cells following respiratory virus infection.

Phenotypically diverse memory CD8 T cells are present in the lungs that either re-circulate or reside within the tissue. Understanding the key cellular interactions that regulate the generation and then persistence of these different subsets is of great interest. Recently, DNGR-1 dendritic cell (DC) mediated priming was reported to control the generation of lung-resident but not circulating memory cells following respiratory viral infection.

HVEM Imprints Memory Potential on Effector CD8 T Cells Required for Protective Mucosal Immunity.

Mucosal immunity to reinfection with a highly virulent virus requires the accumulation and persistence of memory CD8 T cells at the site of primary infection. These cells may derive from memory precursor effector cells (MPECs), which are distinct from short-lived effector cells that provide acute protection but are often destined to die. Using respiratory virus infection, we show that herpes virus entry mediator (HVEM; TNFRSF14), a member of the TNF receptor superfamily, provides key signals for MPEC persistence.

Direct Hydroxylation of Benzene to Phenol by Cytochrome P450BM3 Triggered by Amino Acid Derivatives.

The selective hydroxylation of benzene to phenol, without the formation of side products resulting from overoxidation, is catalyzed by cytochrome P450BM3 with the assistance of amino acid derivatives as decoy molecules. The catalytic turnover rate and the total turnover number reached 259 min  P450BM3 and 40 200 P450BM3 when N-heptyl-l-proline modified with l-phenylalanine (C7-l-Pro-l-Phe) was used as the decoy molecule. This work shows that amino acid derivatives with a totally different structure from fatty acids can be used as decoy molecules for aromatic hydroxylation by wild-type P450BM3.

The Utility of Routine Postoperative Radiographs After Pinning of Pediatric Supracondylar Humerus Fractures.

Background: The purpose of this study was to determine the frequency with which postoperative radiographs resulted in a change in management following closed reduction and percutaneous pinning of displaced pediatric supracondylar humerus fractures. We hypothesize that only the initial postoperative radiograph will lead to changes in management of operative supracondylar humerus fractures.

Methods: A retrospective review was performed at 2 level I pediatric trauma centers.

Comparison of ultraviolet A light protection standards in the United States and European Union through in vitro measurements of commercially available sunscreens.

Background: The importance of adequate ultraviolet A light (UVA) protection has become apparent in recent years. The United States and Europe have different standards for assessing UVA protection in sunscreen products.

Objective: We sought to measure the in vitro critical wavelength (CW) and UVA protection factor (PF) of commercially available US sunscreen products and see if they meet standards set by the United States and the European Union.

Tissue-specific programming of memory CD8 T cell subsets impacts protection against lethal respiratory virus infection.

How tissue-specific anatomical distribution and phenotypic specialization are linked to protective efficacy of memory T cells against reinfection is unclear. Here, we show that lung environmental cues program recently recruited central-like memory cells with migratory potentials for their tissue-specific functions during lethal respiratory virus infection. After entering the lung, some central-like cells retain their original CD27CXCR3 phenotype, enabling them to localize near the infected bronchiolar epithelium and airway lumen to function as the first line of defense against pathogen encounter.