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.

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.

A J-Protein Co-chaperone Recruits BiP to Monomerize IRE1 and Repress the Unfolded Protein Response.

When unfolded proteins accumulate in the endoplasmic reticulum (ER), the unfolded protein response (UPR) increases ER-protein-folding capacity to restore protein-folding homeostasis. Unfolded proteins activate UPR signaling across the ER membrane to the nucleus by promoting oligomerization of IRE1, a conserved transmembrane ER stress receptor. However, the coupling of ER stress to IRE1 oligomerization and activation has remained obscure. Here, we report that the ER luminal co-chaperone ERdj4/DNAJB9 is a selective IRE1 repressor that promotes a complex between the luminal Hsp70 BiP and the luminal stress-sensing domain of IRE1α (IRE1LD). In vitro, ERdj4 is required for complex formation between BiP and IRE1LD. ERdj4 associates with IRE1LD and recruits BiP through the stimulation of ATP hydrolysis, forcibly disrupting IRE1 dimers. Unfolded proteins compete for BiP and restore IRE1LD to its default, dimeric, and active state. These observations establish BiP and its J domain co-chaperones as key regulators of the UPR.

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.

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.

Multistep substrate binding and engagement by the AAA+ ClpXP protease.

Escherichia coli ClpXP is one of the most thoroughly studied AAA+ proteases, but relatively little is known about the reactions that allow it to bind and then engage specific protein substrates before the adenosine triphosphate (ATP)-fueled mechanical unfolding and translocation steps that lead to processive degradation. Here, we employ a fluorescence-quenching assay to study the binding of ssrA-tagged substrates to ClpXP. Polyphasic stopped-flow association and dissociation kinetics support the existence of at least three distinct substrate-bound complexes. These kinetic data fit well to a model in which ClpXP and substrate form an initial recognition complex followed by an intermediate complex and then, an engaged complex that is competent for substrate unfolding. The initial association and dissociation steps do not require ATP hydrolysis, but subsequent forward and reverse kinetic steps are accelerated by faster ATP hydrolysis. Our results, together with recent cryo-EM structures of ClpXP bound to substrates, support a model in which the ssrA degron initially binds in the top portion of the axial channel of the ClpX hexamer and then is translocated deeper into the channel in steps that eventually pull the native portion of the substrate against the channel opening. Reversible initial substrate binding allows ClpXP to check potential substrates for degrons, potentially increasing specificity. Subsequent substrate engagement steps allow ClpXP to grip a wide variety of sequences to ensure efficient unfolding and translocation of almost any native substrate.

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).

Distinct tumor-infiltrating lymphocyte landscapes are associated with clinical outcomes in localized non-small-cell lung cancer.

BACKGROUND: Despite the importance of tumor-infiltrating T lymphocytes (TILs) in cancer biology, the relationship between TIL phenotypes and their prognostic relevance for localized non-small-cell lung cancer (NSCLC) has not been well established. PATIENTS AND METHODS: Fresh tumor and normal adjacent tissue was prospectively collected from 150 patients with localized NSCLC. Tissue was comprehensively characterized by high-dimensional flow cytometry of TILs integrated with immunogenomic data from multiplex immunofluorescence, T-cell receptor sequencing, exome sequencing, RNA sequencing, targeted proteomics, and clinicopathologic features. RESULTS: While neither the magnitude of TIL infiltration nor specific TIL subsets were significantly prognostic alone, the integration of high-dimensional flow cytometry data identified two major immunotypes (IM1 and IM2) that were predictive of recurrence-free survival independent of clinical characteristics. IM2 was associated with poor prognosis and characterized by the presence of proliferating TILs expressing cluster of differentiation 103, programmed cell death protein 1, T-cell immunoglobulin and mucin-domain containing protein 3, and inducible T-cell costimulator. Conversely, IM1 was associated with good prognosis and differentiated by an abundance of CD8+ T cells expressing cytolytic enzymes, CD4+ T cells lacking the expression of inhibitory receptors, and increased levels of B-cell infiltrates and tertiary lymphoid structures. While increased B-cell infiltration was associated with good prognosis, the best prognosis was observed in patients with tumors exhibiting high levels of both B cells and T cells. These findings were validated in patient tumors from The Cancer Genome Atlas. CONCLUSIONS: Our study suggests that although the number of infiltrating T cells is not associated with patient survival, the nature of the infiltrating T cells, resolved in distinct TIL immunotypes, is prognostically relevant in NSCLC and may inform therapeutic approaches to clinical care.

The Best of Both Worlds: A Framework for Combining Degradation Prediction with High Performance Super-Resolution Networks.

To date, the best-performing blind super-resolution (SR) techniques follow one of two paradigms: (A) train standard SR networks on synthetic low-resolution-high-resolution (LR-HR) pairs or (B) predict the degradations of an LR image and then use these to inform a customised SR network. Despite significant progress, subscribers to the former miss out on useful degradation information and followers of the latter rely on weaker SR networks, which are significantly outperformed by the latest architectural advancements. In this work, we present a framework for combining any blind SR prediction mechanism with any deep SR network. We show that a single lightweight metadata insertion block together with a degradation prediction mechanism can allow non-blind SR architectures to rival or outperform state-of-the-art dedicated blind SR networks. We implement various contrastive and iterative degradation prediction schemes and show they are readily compatible with high-performance SR networks such as RCAN and HAN within our framework. Furthermore, we demonstrate our framework's robustness by successfully performing blind SR on images degraded with blurring, noise and compression. This represents the first explicit combined blind prediction and SR of images degraded with such a complex pipeline, acting as a baseline for further advancements.

Opioid Prescribing Practices in Cleft Lip and Cleft Palate Reconstruction.

INTRODUCTION: Currently, there is no consensus regarding the role of opioids in the management of perioperative pain in children undergoing cleft lip/palate repair. METHOD: The present study evaluated opioid prescribing patterns of surgeon members within the American Cleft Palate-Craniofacial Association surgeons utilizing an anonymous survey. RESULTS: Respondents performing cleft lip repair typically operate on patients 3 to 6 months of age (86%), admit patients postoperatively (82%), and discharge them on the first postoperative day (72%). Comparatively, respondents performed palatoplasty between the ages of 10 and 12 months (62%), almost always admit the patients (99%), and typically discharge on the first postoperative day (78%). Narcotics were more frequently prescribed after palatoplasty than after cleft lip repair, both for inpatients (66%; 49%) and at discharge (38%; 22%). Oxycodone was the most prescribed narcotic (39.1%; 41.4%), typically for a duration of 1 to 3 days (81.5%; 81.2%). All surgeons who reported changing their narcotic regimen (34.4% dose, 32.8% duration) after cleft lip repair, decreased both parameters from earlier to later in their career. Similarly, surgeons who changed the dose (32.2%) and duration (42.5%) of narcotics after palatoplasty, mostly decreased both parameters (96%). Additionally, physicians with >15 years of practice were less likely to prescribe opioids in comparison with colleagues with ≤15 years of experience. Ninety-two percent of respondents endorsed prescribing nonopioid analgesics after prescribing cleft surgery, most commonly acetaminophen (85.7%; 85.4%). CONCLUSION: Cleft surgeons typically prescribe opioids to inpatients and rarely upon discharge. Changes to opioid-prescribing patterns typically involved a decreased dose and duration.

Cost and cost-effectiveness of a simplified treatment model with direct-acting antivirals for chronic hepatitis C in Cambodia.

BACKGROUND & AIMS: In 2016, Médecins Sans Frontières established the first general population Hepatitis C virus (HCV) screening and treatment site in Cambodia, offering free direct-acting antiviral (DAA) treatment. This study analysed the cost-effectiveness of this intervention. METHODS: Costs, quality adjusted life years (QALYs) and cost-effectiveness of the intervention were projected with a Markov model over a lifetime horizon, discounted at 3%/year. Patient-level resource-use and outcome data, treatment costs, costs of HCV-related healthcare and EQ-5D-5L health states were collected from an observational cohort study evaluating the effectiveness of DAA treatment under full and simplified models of care compared to no treatment; other model parameters were derived from literature. Incremental cost-effectiveness ratios (cost/QALY gained) were compared to an opportunity cost-based willingness-to-pay threshold for Cambodia ($248/QALY). RESULTS: The total cost of testing and treatment per patient for the full model of care was $925(IQR $668-1631), reducing to $376(IQR $344-422) for the simplified model of care. EQ-5D-5L values varied by fibrosis stage: decompensated cirrhosis had the lowest value, values increased during and following treatment. The simplified model of care was cost saving compared to no treatment, while the full model of care, although cost-effective compared to no treatment ($187/QALY), cost an additional $14 485/QALY compared to the simplified model, above the willingness-to-pay threshold for Cambodia. This result is robust to variation in parameters. CONCLUSIONS: The simplified model of care was cost saving compared to no treatment, emphasizing the importance of simplifying pathways of care for improving access to HCV treatment in low-resource settings.

Targeted Muscle Reinnervation in the Hand: An Anatomical Feasibility Study for Neuroma Treatment and Prevention.

PURPOSE: Targeted muscle reinnervation (TMR) has emerged as a treatment for, and prevention of, symptomatic neuromas and has been reported to be of benefit in the hand. Anatomical studies establishing landmarks for consistent identification of the motor entry points (MEPs) to the intrinsic muscles have not been performed. The purpose of this study was to provide details regarding the MEPs to the intrinsic muscles, determine which MEPs are identifiable dorsally, and develop recommended sensory to MEP nerve coaptations for prophylactic TMR at the time of ray amputation or for management of symptomatic neuromas. METHODS: Motor entry points to the intrinsic hand muscles were dissected in 5 fresh latex-injected cadavers. Number of MEPs, diameter, surface of entry, and distance from dorsal (Lister tubercle) and volar (hamate hook) landmarks were recorded for each target muscle. The digital sensory nerve diameters were measured for size comparison. RESULTS: Motor entry points were identified to all 19 intrinsic muscles through a volar approach and 12 through a dorsal approach. For all fingers, at least 2 MEPs were consistently identified dorsally at the base of each amputation site innervating expendable muscles. Motor entry points to the thenar muscles were only reliably identified through a volar approach. Two recommended nerve coaptations for each digit amputation were identified. All had a favorable sensory-to-MEP diameter ratio less than 2:1. CONCLUSIONS: The intrinsic hand muscles have MEPs at consistent distances from bony landmarks both dorsally and volarly. CLINICAL RELEVANCE: These results can be applied clinically to assist surgeons in identifying the locations of MEPs to the intrinsic muscles when performing TMR in the hand for both neuroma treatment and prevention.

Suppressed immune microenvironment and repertoire in brain metastases from patients with resected non-small-cell lung cancer.

BACKGROUND: The tumor immune microenvironment (TIME) of lung cancer brain metastasis is largely unexplored. We carried out immune profiling and sequencing analysis of paired resected primary tumors and brain metastases of non-small-cell lung carcinoma (NSCLC). PATIENTS AND METHODS: TIME profiling of archival formalin-fixed and paraffin-embedded specimens of paired primary tumors and brain metastases from 39 patients with surgically resected NSCLCs was carried out using a 770 immune gene expression panel and by T-cell receptor beta repertoire (TCRß) sequencing. Immunohistochemistry was carried out for validation. Targeted sequencing was carried out to catalog hot spot mutations in cancer genes. RESULTS: Somatic hot spot mutations were mostly shared between both tumor sites (28/39 patients; 71%). We identified 161 differentially expressed genes, indicating inhibition of dendritic cell maturation, Th1, and leukocyte extravasation signaling pathways, in brain metastases compared with primary tumors (P < 0.01). The proinflammatory cell adhesion molecule vascular cell adhesion protein 1 was significantly suppressed in brain metastases compared with primary tumors. Brain metastases exhibited lower T cell and elevated macrophage infiltration compared with primary tumors (P < 0.001). T-cell clones were expanded in 64% of brain metastases compared with their corresponding primary tumors. Furthermore, while TCR repertoires were largely shared between paired brain metastases and primary tumors, T-cell densities were sparse in the metastases. CONCLUSION: We present findings that suggest that the TIME in brain metastases from NSCLC is immunosuppressed and comprises immune phenotypes (e.g. immunosuppressive tumor-associated macrophages) that may help guide immunotherapeutic strategies for NSCLC brain metastases.

Rapid increases in bat activity and diversity after wetland construction in an urban ecosystem.

Wetland construction can mitigate the biodiversity and water quality losses associated with reduced natural wetland coverage. While beneficial effects of wetland construction for bats have been observed in natural and rural settings, the effects of wetland construction on bats in an urban ecosystem are less understood. We used passive acoustic monitoring to measure bat activity levels and diversity at two constructed wetlands and two control sites on the University of North Carolina Greensboro campus, in Greensboro, North Carolina, USA. We monitored all 4 sites before and after wetland construction. Pre-wetland construction, there were few differences in bat activity and community structure at our sites. After wetland construction, we observed greater activity, attributable to all species we recorded, at wetland sites compared to control sites. Species diversity and species richness were also higher at wetland sites compared to control sites. When comparing the same sites before and after wetland construction, both bat activity and species richness increased after construction, but the effects were seen in Winter and not Spring. Our results demonstrate that bats use constructed wetlands in urban ecosystems similarly to other habitat settings. Increases in bat activity, diversity, and species richness occurred within one year of wetland construction.

Acute Liver Failure of Indeterminate Etiology: A Comprehensive Systematic Approach by An Expert Committee to Establish Causality.

OBJECTIVES: In the United States, the Acute Liver Failure Study Group (ALFSG) registry lists approximately 11% of cases as of indeterminate etiology (IND-ALF) as determined by the respective local site principal investigator (PI). Traditionally, IND-ALF has prompted concern that other viruses or toxins might be implicated. We hypothesized that many IND- ALF cases would have an identifiable etiology upon further investigation. Improving the identification process should reduce the number of truly indeterminate cases. METHODS: Specific definitions for each etiology ("etiology-specific algorithms") were developed by a Causality Adjudication Committee that included six reviewers (each with 20 or more years of experience). Of 2718 patients with ALF, 303 initially deemed IND-ALF by site PIs underwent committee review guided by the algorithms. Acetaminophen (APAP) protein adducts were measured in sera when available, additional HEV testing was performed, and viral sequences sought by microarray analysis and metagenomic next-generation sequencing (mNGS). Study sites were asked to provide liver biopsy and/or explant reports and to update serological findings not reported previously. RESULTS: Nearly half (142, 46.9%) of the 303 IND-ALF cases could be reassigned to a single, defined etiology and rated as highly likely or probable; 11 additional cases, upon review, did not meet ALF criteria. Amongst reassigned etiologies, 45 were previously unrecognized APAP, 34 autoimmune hepatitis (AIH), 24 drug-induced liver injury (DILI), 13 various viral causes, 12 ischemia, and 14 miscellaneous other etiologies. The remaining 150, deemed true IND-ALF, represented just 5.5%. CONCLUSIONS: The indeterminate etiology in ALF includes patients with a diagnosis that is discernible after closer examination. Revision of etiologic diagnoses of indeterminate cases using added testing and expert opinion is useful in understanding all aspects of ALF.

Assessment of Function after Free Tissue Transfer to the Lower Extremity for Chronic Wounds Using the Lower Extremity Functional Scale.

BACKGROUND: Free tissue transfer is one option for preservation of form and function in the native limb, in the setting of soft tissue paucity. However, the data on patient functionality after microvascular intervention is inconsistently reported. The Lower Extremity Function Scale (LEFS) measures patient-reported difficulty in carrying out 20 physical activities, on a Likert scale, the sum of which correlates with descriptive functional stages of 1-5. We assess limb functionality in this cohort of microvascular patients using the LEFS survey. METHODS: A retrospective chart review was conducted at a single academic medical center of 101 consecutive free flaps, from 2011 to 2016. Of the flaps that met inclusion criteria, 39 had completed LEFS surveys. Mean LEFS scores were calculated, and the effects of risk factors such as diabetes, age, and smoking status were analyzed. RESULTS: The mean LEFS score after free tissue transfer was 50.3 (SD ± 21.1), with a mean follow up survey time of 3.0 years (SD ± 1.3). The score correlated with Stage 4 function, or "independent community ambulation," and age was the only demographic factor associated with decreased functionality in this group. This is compared with mean LEFS score of 43.1 (SD ± 18.4) in cohort of 55 below knee amputations (BKAs), and 38.3 (SD ± 14.9) in 28 above knee amputations (AKAs), both correlating with Stage 3 function: "limited community ambulation." CONCLUSIONS: Functional outcomes scores such as the LEFS demonstrate that patients can obtain an adequate level of functionality for independent community activity after free tissue transfer, although functional improvement diminishes with age.

Urban green area provides refuge for native small mammal biodiversity in a rapidly expanding city in Ghana.

Urbanization is a key driver of global biodiversity loss. Although sub-Saharan African countries are experiencing unprecedented urbanization and urban expansion, very little is known about how this impacts tropical biodiversity. Here, we assessed the effects of urban expansion and urban green space on local small mammal species diversity in Accra, Ghana. We surveyed small mammals in the University of Ghana botanical garden, an urban green area (UGA) and adjoining built-up environment (BE) and compared the results with baseline data (BLD) collected when large areas of the current city still remained mostly undeveloped. The methodology involved live-trapping using Sherman collapsible live-traps. Our data showed higher small mammal abundance and diversity in the UGA than BE. Similarity of species composition was higher between UGA and BLD than between BE and BLD. The small mammal species captured in BE (the rodents Mastomys erythroleucus, Rattus rattus, and Arvicanthis rufinus, and the shrew Crocidura olivieri) are known to easily adapt to human-modified landscapes. Our results suggest that urbanization negatively influenced the abundance, diversity, and community composition of small mammals. Efforts should be directed towards the integration of urban green areas into urban land development planning in developing countries in order to conserve local wildlife and ecological services that enhance the quality of urban life.

The Natural History of Severe Acute Liver Injury.

OBJECTIVES: Acute liver failure (ALF) is classically defined by coagulopathy and hepatic encephalopathy (HE); however, acute liver injury (ALI), i.e., severe acute hepatocyte necrosis without HE, has not been carefully defined nor studied. Our aim is to describe the clinical course of specifically defined ALI, including the risk and clinical predictors of poor outcomes, namely progression to ALF, the need for liver transplantation (LT) and death. METHODS: 386 subjects prospectively enrolled in the Acute Liver Failure Study Group registry between 1 September 2008 through 25 October 2013, met criteria for ALI: International Normalized Ratio (INR)≥2.0 and alanine aminotransferase (ALT)≥10 × elevated (irrespective of bilirubin level) for acetaminophen (N-acetyl-p-aminophenol, APAP) ALI, or INR≥2.0, ALT≥10x elevated, and bilirubin≥3.0 mg/dl for non-APAP ALI, both groups without any discernible HE. Subjects who progressed to poor outcomes (ALF, death, LT) were compared, by univariate analysis, with those who recovered. A model to predict poor outcome was developed using the random forest (RF) procedure. RESULTS: Progression to a poor outcome occurred in 90/386 (23%), primarily in non-APAP (71/179, 40%) vs. only 14/194 (7.2%) in APAP patients comprising 52% of all cases (13 cases did not have an etiology assigned; 5 of whom had a poor outcome). Of 82 variables entered into the RF procedure: etiology, bilirubin, INR, APAP level and duration of jaundice were the most predictive of progression to ALF, LT, or death. CONCLUSIONS: A majority of ALI cases are due to APAP, 93% of whom will improve rapidly and fully recover, while non-APAP patients have a far greater risk of poor outcome and should be targeted for early referral to a liver transplant center.

Fluorescence Technology for Point of Care Wound Management.

As the prevalence of chronic wounds continues to rise, the need for point of care wound assessment has also increased. While a variety of technologies have been developed to improve diagnostic abilities and monitoring of wounds, none have proven completely effective in all settings. Further, many of the stalwart wound management techniques remain costly, time consuming, and technically challenging. The two key pivotal events of ischemia and infection can lead to limb loss. A relatively new crop of fluorescence-based technologies, including devices that measure pathogenic auto-fluorescence, fluorescence angiography, or map cutaneous oxygenation, are increasingly being utilized for adjunct wound assessment-both clinical and operative settings can address these events. These technologies offer rapid, efficient, visual, and quantitative data that can aid the wound provider in evaluating the viability of tissues, ensuring adequate perfusion, and optimizing wound bed preparation. In the following review, pathogenic auto-fluorescence is compared to gross evaluation of wound infection and culture based diagnostics, indocyanine green fluorescence angiography is compared to various methods of visual and physical assessments of tissue perfusion by the practitioner, and cutaneous oxygenation is compared to clinical signs of ischemia. We focus on the current applications of fluorescence technologies in wound management, with emphasis placed on the evidence for clinical and operative implementation, a safety analyses, procedural limitations, and the future direction of this growing field of wound assessment.

Potential Future Applications for Negative Pressure Wound Therapy and Installation Devices.

Negative-pressure wound therapy (NPWT) applies vacuum pressure to a wound bed sealed by an adhesive dressing to improve wound healing. A cleansing solution, often antibiotics or saline, may be instilled into the wound bed concurrently and removed via suction, thus enhancing the therapeutic effect. The therapeutic effect results from improved blood flow and removal of inflammatory factors. Since 1995, the FDA has approved NPWT for medical use. Since then, this technology has been applied to different types of wounds, including diabetic and decubitus ulcers and postsurgical incisional wounds. There are many applications for NPWT that remain to be explored. In this article, we postulate on novel and future uses for NPWT, including application in targeted drug delivery, stem cell therapy, and the prospect of combination with filtration devices, adaptable smart dressings, and remote monitoring.