GCN2 in Viral Defence and the Subversive Tactics Employed by Viruses.

The recent SARS-CoV-2 pandemic and associated COVID19 disease illustrates the important role of viral defence mechanisms in ensuring survival and recovery of the host or patient. Viruses absolutely depend on the host's protein synthesis machinery to replicate, meaning that impeding translation is a powerful way to counteract viruses. One major approach used by cells to obstruct protein synthesis is to phosphorylate the alpha subunit of eukaryotic translation initiation factor 2 (eIF2α). Mammals possess four different eIF2α-kinases: PKR, HRI, PEK/PERK, and GCN2. While PKR is currently considered the principal eIF2α-kinase involved in viral defence, the other eIF2α-kinases have also been found to play significant roles. Unsurprisingly, viruses have developed mechanisms to counteract the actions of eIF2α-kinases, or even to exploit them to their benefit. While some of these virulence factors are specific to one eIF2α-kinase, such as GCN2, others target all eIF2α-kinases. This review critically evaluates the current knowledge of viral mechanisms targeting the eIF2α-kinase GCN2. A detailed and in-depth understanding of the molecular mechanisms by which viruses evade host defence mechanisms will help to inform the development of powerful anti-viral measures.

Role of Electronegativity in Environmentally Persistent Free Radicals (EPFRs) Formation on ZnO.

Environmentally persistent free radicals (EPFRs), a group of emerging pollutants, have significantly longer lifetimes than typical free radicals. EPFRs form by the adsorption of organic precursors on a transition metal oxide (TMO) surface involving electron charge transfer between the organic and TMO. In this paper, dihalogenated benzenes were incorporated to study the role of electronegativity in the electron transfer process to obtain a fundamental knowledge of EPFR formation mechanism on ZnO. Upon chemisorption on ZnO nanoparticles at 250 °C, electron paramagnetic resonance (EPR) confirms the formation of oxygen adjacent carbon-centered organic free radicals with concentrations between 1016 and 1017 spins/g. The radical concentrations show a trend of 1,2-dibromobenzene (DBB) > 1,2-dichlorobenzene (DCB) > 1,2-difluorobenzene (DFB) illustrating the role of electronegativity on the amount of radical formation. X-ray absorption spectroscopy (XAS) confirms the reduction of the Zn2+ metal center, contrasting previous experimental evidence of an oxidative mechanism for ZnO single crystal EPFR formation. The extent of Zn reduction for the different organics (DBB > DCB > DFB) also correlates to their polarity. DFT calculations provide theoretical evidence of ZnO surface reduction and exhibit a similar trend of degree of reduction for different organics, further building on the experimental findings. The lifetimes of the EPFRs formed confirm a noteworthy persistency.

Triaging of α-helical proteins to the mitochondrial outer membrane by distinct chaperone machinery based on substrate topology.

Mitochondrial outer membrane ⍺-helical proteins play critical roles in mitochondrial-cytoplasmic communication, but the rules governing the targeting and insertion of these biophysically diverse proteins remain unknown. Here, we first defined the complement of required mammalian biogenesis machinery through genome-wide CRISPRi screens using topologically distinct membrane proteins. Systematic analysis of nine identified factors across 21 diverse ⍺-helical substrates reveals that these components are organized into distinct targeting pathways that act on substrates based on their topology. NAC is required for the efficient targeting of polytopic proteins, whereas signal-anchored proteins require TTC1, a cytosolic chaperone that physically engages substrates. Biochemical and mutational studies reveal that TTC1 employs a conserved TPR domain and a hydrophobic groove in its C-terminal domain to support substrate solubilization and insertion into mitochondria. Thus, the targeting of diverse mitochondrial membrane proteins is achieved through topological triaging in the cytosol using principles with similarities to ER membrane protein biogenesis systems.

Reamer irrigator aspirator (RIA) reduces risk of fat embolism in bilateral pediatric femur shaft fractures: a case report.

A 14-year-old male patient was successfully treated with the reamer irrigator aspirator for femur intramedullary rod preparation after sustaining right and left closed femur fractures because of an all-terrain vehicle accident. In patients already categorized as high risk for fat embolism syndrome, such as those with bilateral femur fractures, reaming both femora greatly increases the likelihood of this complication. The reamer irrigator aspirator provides an effective tool that potentially mitigates the risk of fat embolism syndrome in pediatric patients with this type of orthopedic trauma.

Generative Large Language Models for Detection of Speech Recognition Errors in Radiology Reports.

This study evaluated the ability of generative large language models (LLMs) to detect speech recognition errors in radiology reports. A dataset of 3233 CT and MRI reports was assessed by radiologists for speech recognition errors. Errors were categorized as clinically significant or not clinically significant. Performances of five generative LLMs-GPT-3.5-turbo, GPT-4, text-davinci-003, Llama-v2-70B-chat, and Bard-were compared in detecting these errors, using manual error detection as the reference standard. Prompt engineering was used to optimize model performance. GPT-4 demonstrated high accuracy in detecting clinically significant errors (precision, 76.9%; recall, 100%; F1 score, 86.9%) and not clinically significant errors (precision, 93.9%; recall, 94.7%; F1 score, 94.3%). Text-davinci-003 achieved F1 scores of 72% and 46.6% for clinically significant and not clinically significant errors, respectively. GPT-3.5-turbo obtained 59.1% and 32.2% F1 scores, while Llama-v2-70B-chat scored 72.8% and 47.7%. Bard showed the lowest accuracy, with F1 scores of 47.5% and 20.9%. GPT-4 effectively identified challenging errors of nonsense phrases and internally inconsistent statements. Longer reports, resident dictation, and overnight shifts were associated with higher error rates. In conclusion, advanced generative LLMs show potential for automatic detection of speech recognition errors in radiology reports. Keywords: CT, Large Language Model, Machine Learning, MRI, Natural Language Processing, Radiology Reports, Speech, Unsupervised Learning Supplemental material is available for this article.

Augmented Reality Microsurgery: Proof of Concept for a Novel Approach to Microsurgical Field Visualization in Plastic Surgery.

BACKGROUND: Microsurgery is conducted on tiny anatomical structures such as blood vessels and nerves. Over the past few decades, little has changed in the way plastic surgeons visualize and interact with the microsurgical field. New advances in augmented reality (AR) technology present a novel method for microsurgical field visualization. Voice- and gesture-based commands can be used in real time to adjust the size and position of a digital screen. Surgical decision support and/or navigation may also be used. The authors assess the use of AR in microsurgery. METHODS: The video feed from a Leica Microsystems OHX surgical microscope was streamed to a Microsoft HoloLens2 AR headset. A fellowship-trained microsurgeon and three plastic surgery residents then performed a series of four arterial anastomoses on a chicken thigh model using the AR headset, a surgical microscope, a video microscope (or "exoscope"), and surgical loupes. RESULTS: The AR headset provided an unhindered view of the microsurgical field and peripheral environment. The subjects remarked on the benefits of having the virtual screen track with head movements. The ability of participants to place the microsurgical field in a tailored comfortable, ergonomic position was also noted. Points of improvement were the low image quality compared with current monitors, image latency, and the lack of depth perception. CONCLUSIONS: AR is a useful tool that has the potential to improve microsurgical field visualization and the way surgeons interact with surgical monitors. Improvements in screen resolution, latency, and depth of field are needed.

Measuring the 3-30-300 rule to help cities meet nature access thresholds.

The 3-30-300 rule offers benchmarks for cities to promote equitable nature access. It dictates that individuals should see three trees from their dwelling, have 30 % tree canopy in their neighborhood, and live within 300 m of a high-quality green space. Implementing this demands thorough measurement, monitoring, and evaluation methods, yet little guidance is currently available to pursue these actions. To overcome this gap, we employed an expert-based consensus approach to review the available ways to measure 3-30-300 as well as each measure's strengths and weaknesses. We described seven relevant data and processes: vegetation indices, street level analyses, tree inventories, questionnaires, window view analyses, land cover maps, and green space maps. Based on the reviewed strengths and weaknesses of each measure, we presented a suitability matrix to link recommended measures with each component of the rule. These recommendations included surveys and window-view analyses for the '3 component', high-resolution land cover maps for the '30 component', and green space maps with network analyses for the '300 component'. These methods, responsive to local situations and resources, not only implement the 3-30-300 rule but foster broader dialogue on local desires and requirements. Consequently, these techniques can guide strategic investments in urban greening for health, equity, biodiversity, and climate adaptation.

Triaging of α-helical proteins to the mitochondrial outer membrane by distinct chaperone machinery based on substrate topology.

Mitochondrial outer membrane α-helical proteins play critical roles in mitochondrial-cytoplasmic communication, but the rules governing the targeting and insertion of these biophysically diverse substrates remain unknown. Here, we first defined the complement of required mammalian biogenesis machinery through genome-wide CRISPRi screens using topologically distinct membrane proteins. Systematic analysis of nine identified factors across 21 diverse α-helical substrates reveals that these components are organized into distinct targeting pathways which act on substrates based on their topology. NAC is required for efficient targeting of polytopic proteins whereas signal-anchored proteins require TTC1, a novel cytosolic chaperone which physically engages substrates. Biochemical and mutational studies reveal that TTC1 employs a conserved TPR domain and a hydrophobic groove in its C-terminal domain to support substrate solubilization and insertion into mitochondria. Thus, targeting of diverse mitochondrial membrane proteins is achieved through topological triaging in the cytosol using principles with similarities to ER membrane protein biogenesis systems.

Updates on Enhanced Recovery after Surgery protocols for plastic surgery of the breast and future directions.

Introduction: Perioperative pain control is an important component of any plastic surgery practice. Due to the incorporation of Enhanced Recovery after Surgery (ERAS) protocols, reported pain level, opioid consumption, and hospital length of stay numbers have decreased significantly. This article provides an up-to-date review of current ERAS protocols in use, reviews individual aspects of ERAS protocols, and discusses future directions for the continual improvement of ERAS protocols and control of postoperative pain. ERAS components: ERAS protocols have proven to be excellent methods of decreasing patient pain, opioid consumption, and postanesthesia care unit (PACU) and/or inpatient length of stay. ERAS protocols have three phases: preoperative education and pre-habilitation, intraoperative anesthetic blocks, and a postoperative multimodal analgesia regimen. Intraoperative blocks consist of local anesthetic field blocks and a variety of regional blocks, with lidocaine or lidocaine cocktails. Various studies throughout the surgical literature have demonstrated the efficacy of these aspects and their relevance to the overall goal of decreasing patient pain, both in plastic surgery and other surgical fields. In addition to the individual ERAS phases, ERAS protocols have shown promise in both the inpatient and outpatient sectors of plastic surgery of the breast. Conclusion: ERAS protocols have repeatedly been shown to provide improved patient pain control, decreased hospital or PACU length of stay, decreased opioid use, and cost savings. Although protocols have most commonly been utilized in inpatient plastic surgery procedures of the breast, emerging evidence points towards similar efficacy when used in outpatient procedures. Furthermore, this review demonstrates the efficacy of local anesthetic blocks in controlling patient pain.

Comparative landscape of genetic dependencies in human and chimpanzee stem cells.

Comparative studies of great apes provide a window into our evolutionary past, but the extent and identity of cellular differences that emerged during hominin evolution remain largely unexplored. We established a comparative loss-of-function approach to evaluate whether human cells exhibit distinct genetic dependencies. By performing genome-wide CRISPR interference screens in human and chimpanzee pluripotent stem cells, we identified 75 genes with species-specific effects on cellular proliferation. These genes comprised coherent processes, including cell-cycle progression and lysosomal signaling, which we determined to be human-derived by comparison with orangutan cells. Human-specific robustness to CDK2 and CCNE1 depletion persisted in neural progenitor cells and cerebral organoids, supporting the G1-phase length hypothesis as a potential evolutionary mechanism in human brain expansion. Our findings demonstrate that evolutionary changes in human cells reshaped the landscape of essential genes and establish a platform for systematically uncovering latent cellular and molecular differences between species.

Operative Versus Non-operative Treatment of Medial Epicondyle Fractures in Pediatric Athletes: A Systematic Review.

Treatment of medial epicondyle fractures is controversial in pediatric orthopaedics with a recent trend towards operative fixation in overhead athletes. We performed a systematic review to compare outcomes in operative and non-operatively overhead athletes. A systematic review of the literature was performed. Articles investing pediatric athletes with medial epicondyle fractures treated operatively and non-operatively that reported functional and radiographic outcomes were compiled. We identified 6 studies with a total of 99 patients (52 treated operatively and 47 treated non-operatively). We found a significantly higher union rate with operative treatment (100%) compared to non-operative treatment (76%, p = 0.0025), with equivalent return to sport time and rate. Non-operative treatment had a lower complication and repeat surgery rates (p = 0.009). This study demonstrates lower complication rates and equivalent functional outcomes between operative and non-operatively treated medial epicondyle fractures in athletes. Non-operative treatment is a valid option in these patients. (Journal of Surgical Orthopaedic Advances 32(1):009-013, 2023).

Rapid yeast-based screen for Functionally Relevant Amino Acids (RS-FRAA) in a protein.

Here, we describe a fast and cost-effective procedure to generate a large array of mutant proteins and immediately screen for those with altered protein function. This protocol is a modification from three existing approaches: fusion PCR, Saccharomyces cerevisiae in-yeast recombination, and semi-quantitative growth assays. We also describe a mating step to reduce the occurrence of false positive findings due to ectopic mutations. The only requirement is that the protein elicits a phenotype in Saccharomyces cerevisiae.

Comparative landscape of genetic dependencies in human and chimpanzee stem cells.

Comparative studies of great apes provide a window into our evolutionary past, but the extent and identity of cellular differences that emerged during hominin evolution remain largely unexplored. We established a comparative loss-of-function approach to evaluate whether changes in human cells alter requirements for essential genes. By performing genome-wide CRISPR interference screens in human and chimpanzee pluripotent stem cells, we identified 75 genes with species-specific effects on cellular proliferation. These genes comprised coherent processes, including cell cycle progression and lysosomal signaling, which we determined to be human-derived by comparison with orangutan cells. Human-specific robustness to CDK2 and CCNE1 depletion persisted in neural progenitor cells, providing support for the G1-phase length hypothesis as a potential evolutionary mechanism in human brain expansion. Our findings demonstrate that evolutionary changes in human cells can reshape the landscape of essential genes and establish a platform for systematically uncovering latent cellular and molecular differences between species.

Common Finger Injuries: Treatment Guidelines for Emergency and Primary Care Providers.

INTRODUCTION: Finger and hand injuries are among the most common musculoskeletal conditions presenting to emergency departments and primary care providers. Many rural and community hospitals may not have immediate access to an orthopedic surgeon on-site. Furthermore, military treatment facilities, both within the continental United States and in austere deployment environments, face similar challenges. Therefore, knowing how to treat basic finger and hand injuries is paramount for patient care. MATERIALS AND METHODS: The Armed Forces Health Surveillance Branch operates the Defense Medical Surveillance System, a database that serves as the central repository of medical surveillance data for the armed forces. The Defense Medical Surveillance System was queried for ICD-10 codes associated with finger injuries from 2015 to 2019 among active duty service members across the major branches of the military. RESULTS: The most commonly reported finger injuries were open wounds to fingers without damage to nails, metacarpal fractures, phalanx fractures, and finger subluxation/dislocation. Emergency departments were the most commonly reported treatment facility type accounting for 35% of initial finger injuries, followed by 32.2% at orthopedic surgery clinics, 22.2% at family medicine clinics, and 10.8% at urgent care centers. CONCLUSIONS: Finger injuries are common in the military setting and presenting directly to an orthopedic surgeon does not appear the norm. Fingertip injuries, fractures within the hand, and finger dislocations can often be managed without the need for a subspecialist. By following simple guidelines with attention to "red flags," primary care providers can manage most of these injuries with short-term follow-up with orthopedics.

Decreasing Opioids in Outpatient Breast Surgery with an Enhanced Recovery after Surgery Program and Preoperative Education.

BACKGROUND: Enhanced recovery after surgery (ERAS) programs have been detailed in the literature predominantly in the inpatient setting. The purpose of this study was to determine the effect of an ERAS protocol with a preoperative educational class on opioid prescribing and patient outcomes for outpatient breast surgery. METHODS: An ERAS protocol was formulated focusing on preoperative education, multimodal pain control, and an intraoperative block. The study was conducted as an institutional review board-approved retrospective review. Women undergoing breast reconstruction revision, breast reduction, delayed insertion of prosthesis, tissue expander to implant exchange, and matching procedures were included. The patients were separated into pre-ERAS and ERAS cohorts. Data on demographic characteristics, postanesthesia care unit (PACU) length of stay, PACU oral morphine equivalent (OME) consumption, outpatient OME prescriptions, major and minor complications, and need for additional opioid prescriptions were collected. Analysis was performed with the Fisher exact test or chi-square test as appropriate. RESULTS: Group 1 (pre-ERAS) and group 2 (ERAS) each included 68 patients. The cohorts had similar age, body mass index, diabetes status, and tobacco use. Group 1 was prescribed an average of 216 OMEs, compared with 126.4 OMEs for group 2, a 41.5% decrease ( P < 0.0001). The pre-ERAS group consumed an average of 23.3 OMEs in the PACU versus 16.6 OMEs in the ERAS group ( P = 0.005). Fewer patients in the ERAS group required additional prescriptions for narcotic pain medication at postoperative follow-up ( P = 0.116). No differences were seen in major or minor complications. CONCLUSION: An ERAS protocol that uses a multimodal approach to pain control and preoperative patient education is useful in the outpatient setting and can help decrease opioid consumption. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Repeat-associated non-AUG translation induces cytoplasmic aggregation of CAG repeat-containing RNAs.

CAG trinucleotide repeat expansions cause several neurodegenerative diseases, including Huntington's disease and spinocerebellar ataxia. RNAs with expanded CAG repeats contribute to disease in two unusual ways. First, these repeat-containing RNAs may agglomerate in the nucleus as foci that sequester several RNA-binding proteins. Second, these RNAs may undergo aberrant repeat-associated non-AUG (RAN) translation in multiple frames and produce aggregation-prone proteins. The relationship between RAN translation and RNA foci, and their relative contributions to cellular dysfunction, are unclear. Here, we show that CAG repeat-containing RNAs that undergo RAN translation first accumulate at nuclear foci and, over time, are exported to the cytoplasm. In the cytoplasm, these RNAs are initially dispersed but, upon RAN translation, aggregate with the RAN translation products. These RNA-RAN protein agglomerates sequester various RNA-binding proteins and are associated with the disruption of nucleocytoplasmic transport and cell death. In contrast, RNA accumulation at nuclear foci alone does not produce discernable defects in nucleocytoplasmic transport or cell viability. Inhibition of RAN translation prevents cytoplasmic RNA aggregation and alleviates cell toxicity. Our findings demonstrate that RAN translation-induced RNA-protein aggregation correlates with the key pathological hallmarks observed in disease and suggest that cytoplasmic RNA aggregation may be an underappreciated phenomenon in CAG trinucleotide repeat expansion disorders.

Predictive Drug Release Modeling Across Dissolution Apparatuses I and II using Computational Fluid Dynamics.

A modeling process is developed and validated with which active pharmaceutical ingredient (API) release is predicted across the United States Pharmacopeia (USP) dissolution apparatuses I and II based on limited experimental dissolution data (at minimum two dissolution profiles at different apparatus settings). The process accounts for formulation-specific drug release behavior and hydrodynamics in the apparatuses over the range of typical agitation rates and medium volumes. This modeling process involves measurement of experimental mass transfer coefficients via a conventional mass balance and the relationship of said mass transfer coefficients to hydrodynamics and apparatus setting via computational fluid dynamics (CFD). A novel 1-D model is hence established, which provided calibration data for a particular formulation, can model mass transfer coefficients and their corresponding drug release at apparatus configurations of interest. Based on validation against experimental data produced from five erosion-based formulations over a range of apparatus configurations, accuracy within 8 %LA (labelled amount of API) and an average root mean square deviation of 3 %LA is achieved. With this predictive capability, minimizing the number of dissolution experiments and the amount of chemical materials needed during method development appears feasible.

Mapping information-rich genotype-phenotype landscapes with genome-scale Perturb-seq.

A central goal of genetics is to define the relationships between genotypes and phenotypes. High-content phenotypic screens such as Perturb-seq (CRISPR-based screens with single-cell RNA-sequencing readouts) enable massively parallel functional genomic mapping but, to date, have been used at limited scales. Here, we perform genome-scale Perturb-seq targeting all expressed genes with CRISPR interference (CRISPRi) across >2.5 million human cells. We use transcriptional phenotypes to predict the function of poorly characterized genes, uncovering new regulators of ribosome biogenesis (including CCDC86, ZNF236, and SPATA5L1), transcription (C7orf26), and mitochondrial respiration (TMEM242). In addition to assigning gene function, single-cell transcriptional phenotypes allow for in-depth dissection of complex cellular phenomena-from RNA processing to differentiation. We leverage this ability to systematically identify genetic drivers and consequences of aneuploidy and to discover an unanticipated layer of stress-specific regulation of the mitochondrial genome. Our information-rich genotype-phenotype map reveals a multidimensional portrait of gene and cellular function.

Comparison of Liposomal Bupivacaine to a Local Analgesic Cocktail for Transversus Abdominis Plane Blocks in Abdominally Based Microvascular Breast Reconstruction.

BACKGROUND: Transversus abdominis plane blocks can improve pain control and decrease opioid use within an enhanced recovery after surgery (ERAS) protocol in patients undergoing abdominally based autologous breast reconstruction. The authors have transitioned to using a local analgesic cocktail for transversus abdominis plane blocks. The purpose of this study was to compare postoperative opioid use in patients who received the blocks. METHODS: Patients who underwent abdominally based autologous breast reconstruction between November of 2015 and December of 2019 were retrospectively reviewed. The study group received bupivacaine, ketorolac, dexmedetomidine, and dexamethasone; the control group received liposomal bupivacaine with or without bupivacaine, ketorolac, or dexmedetomidine, as a transversus abdominis plane block. The primary outcome of interest was postoperative opioid use and pain scores. RESULTS: One hundred four women met inclusion criteria: 36 in group A (before ERAS, before transversus abdominis plane block), 38 in group B (ERAS, transversus abdominis plane block with liposomal bupivacaine), and 30 in group C (ERAS, transversus abdominis plane block with local anesthetic cocktail). Total daily oral morphine equivalent consumption (group A, 633; group B, 240; group C, 135; p < 0.0001) and average daily oral morphine equivalent consumption (group A, 137; group B, 56; group C, 29; p < 0.0001) were significantly less for group C in the inpatient phase. Patients in group C were prescribed significantly fewer outpatient oral morphine equivalents (group A, 79; group B, 74; group C, 52; p = 0.01). CONCLUSIONS: Transversus abdominis plane blocks are a significant component of an ERAS protocol for abdominally based breast reconstruction. Liposomal bupivacaine is a popular option for transversus abdominis plane blocks. The authors' results demonstrate that a local anesthetic cocktail, composed of economical and readily available medications, can provide excellent patient pain control and decrease postoperative opioid use. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Developing, Losing, and Regaining Trust in the Doctor-Patient Relationship.

The Psychiatric Consultation Service at Massachusetts General Hospital sees medical and surgical inpatients with comorbid psychiatric symptoms and conditions. During their twice-weekly rounds, Dr Stern and other members of the Consultation Service discuss diagnosis and management of hospitalized patients with complex medical or surgical problems who also demonstrate psychiatric symptoms or conditions. These discussions have given rise to rounds reports that will prove useful for clinicians practicing at the interface of medicine and psychiatry.