Demonstration of Inappropriate Validation Method for a Cracker Baking Process Using Predictive Modeling.

Validation of baking processes for the inactivation of Salmonella is complicated by the combined effects of product heating and drying. The goal of this study was to quantitatively evaluate a previously disseminated approach to validating baking processes utilizing a predictive model developed using only isothermal and single-moisture inactivation data for the initially formulated dough. A simple cracker dough was formulated using flour inoculated with a five-strain cocktail of Salmonella. Side-by-side isothermal and baking experiments were performed to estimate Salmonella inactivation kinetics and to quantify survivors in a dynamic environment, respectively. Isothermal, single-moisture inactivation experiments were performed with cracker dough (water activity, aw = 0.956 ± 0.002; moisture content = 0.50 ± 0.01 dry basis) at three temperatures (56, 60, or 63°C) with ≥6 time intervals. Baking experiments were performed in a convection oven at 177°C with samples pulled every 30 s up to 360 s, with an endpoint product aw (25°C) of 0.45. The Salmonella isothermal, single-moisture inactivation kinetics in cracker dough resulted in D60°C and z values of 4.6 min and 4.9°C, respectively; this model was then integrated over the dynamic product temperature profiles from the baking experiments. In the baking experiments, an average of 5-log reductions of Salmonella was achieved by 150 s of treatment; however, >100-log reductions were predicted by the dough-based models at that time point. This fail-dangerous overestimation of Salmonella lethality in crackers explicitly demonstrated that single-level moisture-based prediction models are inappropriate for describing inactivation in a process with both dynamic temperature and moisture, and that model-based validations must incorporate moisture/aw. Furthermore, end-users should exercise caution when utilizing unvalidated models to validate preventive control processes.

Emerging roles of type 1 innate lymphoid cells in tumour pathogenesis and cancer immunotherapy.

Innate lymphoid cells (ILCs) are the most recently discovered class of innate immune cells found to have prominent roles in various human immune-related pathologies such as infection and autoimmune diseases. However, their role in cancer was largely unclear until recently, where several emerging studies over the past few years unanimously demonstrate ILCs to be critical players in tumour immunity. Being the innate counterpart of T cells, ILCs are potent cytokine producers through which they orchestrate the overall immune response upstream of adaptive immunity thereby modulating T cell function. Out of the major ILC subsets, ILC1s have gained significant traction as potential immunotherapeutic candidates due to their central involvement with the anti-tumour type 1 immune response. ILC1s are potent producers of the well-established anti-tumour cytokine interferon γ (IFNγ), and exert direct cytotoxicity against cancer cells in response to the cytokine interleukin-15 (IL-15). However, in advanced diseases, ILC1s are found to demonstrate an exhausted phenotype in the tumour microenvironment (TME) with impaired effector functions, characterised by decreased responsiveness to cytokines and reduced IFNγ production. Tumour cells produce immunomodulatory cytokines such as transforming growth factor ß (TGFß) and IL-23, and through these suppress ILC1 anti-tumour actfivities and converts ILC1s to pro-tumoural ILC3s respectively, resulting in disease progression. This review provides a comprehensive overview of ILC1s in tumour immunity, and discusses the exciting prospects of harnessing ILC1s for cancer immunotherapy, either alone or in combination with cytokine-based treatment. The exciting prospects of targeting the upstream innate immune system through ILC1s may surmount the limitations associated with adaptive immune T cell-based strategies used in the clinic currently, and overcome cancer immunotherapeutic resistance.

Around-the-knee osteotomies part II: Surgical indications, techniques and outcomes - State of the art.

Recent advances in surgical techniques and planning for knee-based osteotomies have led to improvements in addressing lower extremity malalignment. Part 1 of this review presented the biomechanical and clinical rationale of osteotomies, emphasizing the importance of osteotomies for restoring normal knee kinematics. In Part 2 of this review, indications, surgical technique and outcomes of osteotomies to correct coronal, sagittal and axial plane deformities will be examined. Traditional high tibial and distal femoral osteotomies will be discussed in addition to more recent advanced techniques including biplanar corrections and double-level osteotomies, as well as slope-correcting osteotomies. Patient-specific instrumentation and its use in more complex corrections will also be addressed.

Risk factors for hepatocellular carcinoma associated with hepatitis C genotype 3 infection: A systematic review.

BACKGROUND: Hepatitis C virus (HCV) is a blood-borne virus which globally affects around 79 million people and is associated with high morbidity and mortality. Chronic infection leads to cirrhosis in a large proportion of patients and often causes hepatocellular carcinoma (HCC) in people with cirrhosis. Of the 6 HCV genotypes (G1-G6), genotype-3 accounts for 17.9% of infections. HCV genotype-3 responds least well to directly-acting antivirals and patients with genotype-3 infection are at increased risk of HCC even if they do not have cirrhosis. AIM: To systematically review and critically appraise all risk factors for HCC secondary to HCV-G3 in all settings. Consequently, we studied possible risk factors for HCC due to HCV-G3 in the literature from 1946 to 2023. METHODS: This systematic review aimed to synthesise existing and published studies of risk factors for HCC secondary to HCV genotype-3 and evaluate their strengths and limitations. We searched Web of Science, Medline, EMBASE, and CENTRAL for publications reporting risk factors for HCC due to HCV genotype-3 in all settings, 1946-2023. RESULTS: Four thousand one hundred and forty-four records were identified from the four databases with 260 records removed as duplicates. Three thousand eight hundred and eighty-four records were screened with 3514 excluded. Three hundred and seventy-one full-texts were assessed for eligibility with seven studies included for analysis. Of the seven studies, three studies were retrospective case-control trials, two retrospective cohort studies, one a prospective cohort study and one a cross-sectional study design. All were based in hospital settings with four in Pakistan, two in South Korea and one in the United States. The total number of participants were 9621 of which 167 developed HCC (1.7%). All seven studies found cirrhosis to be a risk factor for HCC secondary to HCV genotype-3 followed by higher age (five-studies), with two studies each showing male sex, high alpha feto-protein, directly-acting antivirals treatment and achievement of sustained virologic response as risk factors for developing HCC. CONCLUSION: Although, studies have shown that HCV genotype-3 infection is an independent risk factor for end-stage liver disease, HCC, and liver-related death, there is a lack of evidence for specific risk factors for HCC secondary to HCV genotype-3. Only cirrhosis and age have demonstrated an association; however, the number of studies is very small, and more research is required to investigate risk factors for HCC secondary to HCV genotype-3.

Reverse total shoulder arthroplasty for primary osteoarthritis with restricted preoperative forward elevation demonstrates similar outcomes but faster range of motion recovery compared to anatomic total shoulder arthroplasty.

BACKGROUND: Reverse total shoulder arthroplasty (RSA) has been increasingly utilized for a variety of shoulder pathologies that are difficult to treat with anatomical total shoulder arthroplasty (TSA). Few studies have compared the outcomes of TSA vs. RSA in patients with cuff intact glenohumeral osteoarthritis and poor preoperative forward elevation. This study aimed to determine whether there is a difference in functional outcomes and postoperative range of motion (ROM) between TSA and RSA in these patients. METHODS: This retrospective cohort study included 116 patients who underwent RSA or TSA between 2013 and 2022 for the treatment of rotator cuff intact primary osteoarthritis with restricted preoperative forward flexion (FF) and a minimum 1-year follow-up. Each arthroplasty group was divided into 2 subgroups: patients with preoperative FF between 91° and 120° or FF lower than or equal to 90°. Patients' clinical outcomes, including active ROM, American Shoulder and Elbow Surgeons score, visual analog scale for pain, and subjective shoulder value were collected. Clinical and radiographic complications were evaluated. RESULTS: There was no significant difference between RSA and TSA in terms of sex (58.3% male vs. 62.2% male, P = .692), or follow-up duration (20.1 months vs. 17.7 months, P = .230). However, the RSA cohort was significantly older (72.0 ± 8.2 vs. 65.4 ± 10.6, P = .012) and weaker in FF and (ER) before surgery (P < .001). There was no difference between RSA (57 patients) and TSA (59 patients) in visual analog scale pain score (1.2 ± 2.3 vs. 1.3 ± 2.3, P = .925), subjective shoulder value score (90 ± 15 vs. 90 ± 15, P = .859), or American Shoulder and Elbow Surgeons score (78.4 ± 20.5 vs. 82.1 ± 23.2, P = .476). Postoperative active ROM was statistically similar between RSA and TSA cohorts in FF (145 ± 26 vs. 146 ± 23, P = .728) and ER (39 ± 15 vs. 41 ± 15, P = .584). However, internal rotation was lower in the RSA cohort (P < .001). This was also true in each subgroup. RSA led to faster postoperative FF and ER achievement at 3 months (P < .001). There was no statistically significant difference in complication rates between cohorts. CONCLUSION: This study demonstrates that patients with glenohumeral osteoarthritis who have a structurally intact rotator cuff but limited preoperative forward elevation can achieve predictable clinical improvement in pain, ROM, and function after either TSA or RSA. Reverse arthroplasty may be a reliable treatment option in patients at risk for developing rotator cuff failure.

Early treatment with fluvoxamine, bromhexine, cyproheptadine, and niclosamide to prevent clinical deterioration in patients with symptomatic COVID-19: a randomized clinical trial.

Background: Repurposed drugs with host-directed antiviral and immunomodulatory properties have shown promise in the treatment of COVID-19, but few trials have studied combinations of these agents. The aim of this trial was to assess the effectiveness of affordable, widely available, repurposed drugs used in combination for treatment of COVID-19, which may be particularly relevant to low-resource countries. Methods: We conducted an open-label, randomized, outpatient, controlled trial in Thailand from October 1, 2021, to June 21, 2022, to assess whether early treatment within 48-h of symptoms onset with combinations of fluvoxamine, bromhexine, cyproheptadine, and niclosamide, given to adults with confirmed mild SARS-CoV-2 infection, can prevent 28-day clinical deterioration compared to standard care. Participants were randomly assigned to receive treatment with fluvoxamine alone, fluvoxamine + bromhexine, fluvoxamine + cyproheptadine, niclosamide + bromhexine, or standard care. The primary outcome measured was clinical deterioration within 9, 14, or 28 days using a 6-point ordinal scale. This trial is registered with ClinicalTrials.gov (NCT05087381). Findings: Among 1900 recruited, a total of 995 participants completed the trial. No participants had clinical deterioration by day 9, 14, or 28 days among those treated with fluvoxamine plus bromhexine (0%), fluvoxamine plus cyproheptadine (0%), or niclosamide plus bromhexine (0%). Nine participants (5.6%) in the fluvoxamine arm had clinical deterioration by day 28, requiring low-flow oxygen. In contrast, most standard care arm participants had clinical deterioration by 9, 14, and 28 days. By day 9, 32.7% (110) of patients in the standard care arm had been hospitalized without requiring supplemental oxygen but needing ongoing medical care. By day 28, this percentage increased to 37.5% (21). Additionally, 20.8% (70) of patients in the standard care arm required low-flow oxygen by day 9, and 12.5% (16) needed non-invasive or mechanical ventilation by day 28. All treated groups significantly differed from the standard care group by days 9, 14, and 28 (p < 0.0001). Also, by day 28, the three 2-drug treatments were significantly better than the fluvoxamine arm (p < 0.0001). No deaths occurred in any study group. Compared to standard care, participants treated with the combination agents had significantly decreased viral loads as early as day 3 of treatment (p < 0.0001), decreased levels of serum cytokines interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1ß) as early as day 5 of treatment, and interleukin-8 (IL-8) by day 7 of treatment (p < 0.0001) and lower incidence of post-acute sequelae of COVID-19 (PASC) symptoms (p < 0.0001). 23 serious adverse events occurred in the standard care arm, while only 1 serious adverse event was reported in the fluvoxamine arm, and zero serious adverse events occurred in the other arms. Interpretation: Early treatment with these combinations among outpatients diagnosed with COVID-19 was associated with lower likelihood of clinical deterioration, and with significant and rapid reduction in the viral load and serum cytokines, and with lower burden of PASC symptoms. When started very soon after symptom onset, these repurposed drugs have high potential to prevent clinical deterioration and death in vaccinated and unvaccinated COVID-19 patients. Funding: Ped Thai Su Phai (Thai Ducks Fighting Danger) social giver group.

Simple ammonium salt and sigma-1 receptor ligand dipentylammonium provides neuroprotective effects in cell culture and Caenorhabditis elegans models of Alzheimer's disease.

The sigma-1 receptor (σ-1R), a chaperone protein located at the mitochondria-associated membrane (MAM) of the endoplasmic reticulum, can interact with and modify the signaling pathways of various proteins, thereby modulating many disease pathologies, including Alzheimer's disease (AD). The σ-1R ligand dipentylammonium (DPA) was analyzed for its anti-AD properties using PC12 cells (in vitro) and Caenorhabditis elegans (in vivo) models along with molecular docking (in silico) analysis. DPA at 1 and 10 µM concentrations was able to significantly potentiate NGF-induced neurite growth length by 137.7 ± 12.0 and 187.8 ± 16.4, respectively, when compared to the control 76.9 ± 7.4. DPA also regulated neurite damage caused by Aß(25-35) treatment in differentiated PC12 cells by improving cell viability and neurite length. In C. elegans, DPA could significantly extend the median and maximum lifespan of Aß transgenic strain CL2006 without impacting wild-type nematodes. Additionally, it could significantly reduce the paralysis phenotype of another Aß transgenic strain, CL4176, thereby improving the overall health in AD pathogenesis. This effect depended on σ-1R, as DPA could not modulate the lifespan of σ-1R mutant TM3443. This was further confirmed using agonist PRE084 and antagonist BD1047, wherein the agonist alone could extend the lifespan of CL2006, while the antagonist suppressed the effect of DPA in CL2006. Interestingly, neither had an TM3443. Further, molecular docking analysis showed that DPA had a similar binding affinity as that of PRE084, BD1047 and pentazocine against the σ-1R receptor in humans and C. elegans, which collectively suggests the anti-AD properties of DPA.

Early Beta-Blocker Utilization in Critically Ill Patients With Moderate-Severe Traumatic Brain Injury: A Retrospective Cohort Study.

BACKGROUND: There is limited evidence that beta-blockers may provide benefit for patients with moderate-severe traumatic brain injury (TBI) during the acute injury period. Larger studies on utilization patterns and impact on outcomes in clinical practice are lacking. OBJECTIVE: The present study uses a large, national hospital claims-based dataset to examine early beta-blocker utilization patterns and its association with clinical outcomes among critically ill patients with moderate-severe TBI. METHODS: We conducted a retrospective cohort study of the administrative claims Premier Healthcare Database of adults (≥17 years) with moderate-severe TBI admitted to the intensive care unit (ICU) from 2016 to 2020. The exposure was receipt of a beta-blocker during day 1 or 2 of ICU stay (BB+). The primary outcome was hospital mortality, and secondary outcomes were: hospital length of stay (LOS), ICU LOS, discharge to home, and vasopressor utilization. In a sensitivity analysis, we explored the association of beta-blocker class (cardioselective and noncardioselective) with hospital mortality. We used propensity weighting methods to address possible confounding by treatment indication. RESULTS: A total of 109 665 participants met inclusion criteria and 39% (n = 42 489) were exposed to beta-blockers during the first 2 days of hospitalization. Of those, 42% received cardioselective only, 43% received noncardioselective only, and 14% received both. After adjustment, there was no association with hospital mortality in the BB+ group compared to the BB- group (adjusted odds ratio [OR] = 0.99, 95% confidence interval [CI] = 0.94, 1.04). The BB+ group had longer hospital stays, lower chance of discharged home, and lower risk of vasopressor utilization, although these difference were clinically small. Beta-blocker class was not associated with hospital mortality. CONCLUSION: In this retrospective cohort study, we found variation in use of beta-blockers and early exposure was not associated with hospital mortality. Further research is necessary to understand the optimal type, dose, and timing of beta-blockers for this population.

Association of Early Dexmedetomidine Utilization With Clinical Outcomes After Moderate-Severe Traumatic Brain Injury: A Retrospective Cohort Study.

BACKGROUND: Traumatic brain injury (TBI) is an expensive and common public health problem. Management of TBI oftentimes includes sedation to facilitate mechanical ventilation (MV) for airway protection. Dexmedetomidine has emerged as a potential candidate for improved patient outcomes when used for early sedation after TBI due to its potential modulation of autonomic dysfunction. We examined early sedation patterns, as well as the association of dexmedetomidine exposure with clinical and functional outcomes among mechanically ventilated patients with moderate-severe TBI (msTBI) in the United States. METHODS: We conducted a retrospective cohort study using data from the Premier dataset and identified a cohort of critically ill adult patients with msTBI who required MV from January 2016 to June 2020. msTBI was defined by head-neck abbreviated injury scale (AIS) values of 3 (serious), 4 (severe), and 5 (critical). We described early continuous sedative utilization patterns. Using propensity-matched models, we examined the association of early dexmedetomidine exposure (within 2 days of intensive care unit [ICU] admission) with the primary outcome of hospital mortality and the following secondary outcomes: hospital length of stay (LOS), days on MV, vasopressor use after the first 2 days of admission, hemodialysis (HD) after the first 2 days of admission, hospital costs, and discharge disposition. All medications, treatments, and procedures were identified using date-stamped hospital charge codes. RESULTS: The study population included 19,751 subjects who required MV within 2 days of ICU admission. The patients were majority male and white. From 2016 to 2020, the annual percent utilization of dexmedetomidine increased from 4.05% to 8.60%. After propensity score matching, early dexmedetomidine exposure was associated with reduced odds of hospital mortality (odds ratio [OR], 0.59; 95% confidence interval [CI], 0.47-0.74; P < .0001), increased risk for liberation from MV (hazard ratio [HR], 1.20; 95% CI, 1.09-1.33; P = .0003), and reduced LOS (HR, 1.11; 95% CI, 1.01-1.22; P = .033). Exposure to early dexmedetomidine was not associated with odds of HD (OR, 1.14; 95% CI, 0.73-1.78; P = .56), vasopressor utilization (OR, 1.10; 95% CI, 0.78-1.55; P = .60), or increased hospital costs (relative cost ratio, 1.98; 95% CI, 0.93-1.03; P = .66). CONCLUSIONS: Dexmedetomidine is being utilized increasingly as a sedative for mechanically ventilated patients with msTBI. Early dexmedetomidine exposure may lead to improved patient outcomes in this population.

The live biotherapeutic SYNB1353 decreases plasma methionine via directed degradation in animal models and healthy volunteers.

Methionine is an essential proteinogenic amino acid, but its excess can lead to deleterious effects. Inborn errors of methionine metabolism resulting from loss of function in cystathionine ß-synthase (CBS) cause classic homocystinuria (HCU), which is managed by a methionine-restricted diet. Synthetic biotics are gastrointestinal tract-targeted live biotherapeutics that can be engineered to replicate the benefits of dietary restriction. In this study, we assess whether SYNB1353, an E. coli Nissle 1917 derivative, impacts circulating methionine and homocysteine levels in animals and healthy volunteers. In both mice and nonhuman primates (NHPs), SYNB1353 blunts the appearance of plasma methionine and plasma homocysteine in response to an oral methionine load. A phase 1 clinical study conducted in healthy volunteers subjected to an oral methionine challenge demonstrates that SYNB1353 is well tolerated and blunts plasma methionine by 26%. Overall, SYNB1353 represents a promising approach for methionine reduction with potential utility for the treatment of HCU.

Quantifying forms and functions of intestinal bile acid pools in mice.

Bile acids (BAs) are gastrointestinal metabolites that serve dual functions in lipid absorption and cell signaling. BAs circulate actively between the liver and distal small intestine (i.e., ileum), yet the dynamics through which complex BA pools are absorbed in the ileum and interact with intestinal cells in vivo remain ill-defined. Through multi-site sampling of nearly 100 BA species in individual wild type mice, as well as mice lacking the ileal BA transporter, Asbt/Slc10a2, we calculate the ileal BA pool in fasting C57BL/6J mice to be ~0.3 µmoles/g. Asbt-mediated transport accounts for ~80% of this pool and amplifies size, whereas passive absorption explains the remaining ~20%, and generates diversity. Accordingly, ileal BA pools in mice lacking Asbt are ~5-fold smaller than in wild type controls, enriched in secondary BA species normally found in the colon, and elicit unique transcriptional responses in cultured ileal explants. This work quantitatively defines ileal BA pools in mice and reveals how BA dysmetabolism can impinge on intestinal physiology.

Network analysis-guided drug repurposing strategies targeting LPAR receptor in the interplay of COVID, Alzheimer's, and diabetes.

The COVID-19 pandemic caused by the SARS-CoV-2 virus has greatly affected global health. Emerging evidence suggests a complex interplay between Alzheimer's disease (AD), diabetes (DM), and COVID-19. Given COVID-19's involvement in the increased risk of other diseases, there is an urgent need to identify novel targets and drugs to combat these interconnected health challenges. Lysophosphatidic acid receptors (LPARs), belonging to the G protein-coupled receptor family, have been implicated in various pathological conditions, including inflammation. In this regard, the study aimed to investigate the involvement of LPARs (specifically LPAR1, 3, 6) in the tri-directional relationship between AD, DM, and COVID-19 through network analysis, as well as explore the therapeutic potential of selected anti-AD, anti-DM drugs as LPAR, SPIKE antagonists. We used the Coremine Medical database to identify genes related to DM, AD, and COVID-19. Furthermore, STRING analysis was used to identify the interacting partners of LPAR1, LPAR3, and LPAR6. Additionally, a literature search revealed 78 drugs on the market or in clinical studies that were used for treating either AD or DM. We carried out docking analysis of these drugs against the LPAR1, LPAR3, and LPAR6. Furthermore, we modeled the LPAR1, LPAR3, and LPAR6 in a complex with the COVID-19 spike protein and performed a docking study of selected drugs with the LPAR-Spike complex. The analysis revealed 177 common genes implicated in AD, DM, and COVID-19. Protein-protein docking analysis demonstrated that LPAR (1,3 & 6) efficiently binds with the viral SPIKE protein, suggesting them as targets for viral infection. Furthermore, docking analysis of the anti-AD and anti-DM drugs against LPARs, SPIKE protein, and the LPARs-SPIKE complex revealed promising candidates, including lupron, neflamapimod, and nilotinib, stating the importance of drug repurposing in the drug discovery process. These drugs exhibited the ability to bind and inhibit the LPAR receptor activity and the SPIKE protein and interfere with LPAR-SPIKE protein interaction. Through a combined network and targeted-based therapeutic intervention approach, this study has identified several drugs that could be repurposed for treating COVID-19 due to their expected interference with LPAR(1, 3, and 6) and spike protein complexes. In addition, it can also be hypothesized that the co-administration of these identified drugs during COVID-19 infection may not only help mitigate the impact of the virus but also potentially contribute to the prevention or management of post-COVID complications related to AD and DM.

A machine learning-based algorithm to identify U-500R insulin candidates among adults with type 2 diabetes mellitus in US retrospective databases.

OBJECTIVE: To develop a machine learning-based predictive algorithm to identify patients with type 2 diabetes mellitus (T2DM) who are candidates for initiation of U-500R insulin (U-500R). METHODS: A retrospective cohort of patients with T2DM was used from a large US administrative claims and electronic health records (EHR) database affiliated with Optum. Predictor variables derived from the data were used to identify appropriate supervised machine learning models including least absolute shrinkage and selection operator (LASSO) and extreme gradient boosted (XGBoost) methods. Predictive performance was assessed using precision-recall (PR) and receiver operating characteristic (ROC) area under the curve (AUC). The clinical interpretation of the final model was supported by fitting the final set of variables from the LASSO and XGBoost models to a traditional logistic regression model. Model choice was determined by comparing Akaike Information Criterion (AIC), residual deviances, and scaled Brier scores. RESULTS: Among 81,242 patients who met the study eligibility criteria, 577 initiated U-500R and were assigned to the positive class. Predictors of U-500R initiation included overweight/obesity, neuropathy, HbA1c ≥9% and 8%-9%, BUN 23.8 to <112 mg/dl, ALT 35.9-2056.2 U/L, no radiological chest exams, no GFR labs, and gait/mobility abnormalities. The best performing model was the LASSO model with an ROC AUC of 0.776 on the hold-out test set. CONCLUSION: This study successfully developed and validated a machine learning-based algorithm to identify U-500R candidates among patients with T2DM. This may help health care providers and decision-makers to understand important characteristics of patients who could use U-500R therapies which in turn could support policies and guidelines for optimal patient management.

Editorial Commentary: Revision Meniscal Allograft Transplantation is a Bridge Option for Appropriately Indicated Patients With Realistic Patient Expectations in the Hands of Experienced Knee Surgeons Able to Perform All Necessary Concomitant Procedures.

Primary meniscal allograft transplantation (PMAT) is an effective yet sometimes short-term solution to postmeniscectomy syndrome. Survivorship beyond 10 years can carry a guarded prognosis. Alternatives after failure of PMAT are typically total or unicompartmental arthroplasty, which, depending on desired activity level, can be reasonable options for older patients. However, when faced with younger, otherwise healthy patients, revision meniscal allograft transplantation (RMAT) shows outcomes in appropriately indicated patients when concomitant pathology is also addressed. Patient expectations must be tempered (i.e., they should not expect to achieve an International Knee Documentation Committee score of 70 to 100, but rather 40 to 70 meaning that a patient can function reasonably well in activities of daily living). Thus RMAT is a viable "salvage" or "bridge" option in the hands of experienced high-volume knee surgeons (to ensure meticulous surgical technique and the ability to perform all necessary concomitant procedures). Patients must have appropriate expectations and be appropriately indicated.

CTCF regulates hepatitis B virus cccDNA chromatin topology.

Hepatitis B Virus (HBV) is a small DNA virus that replicates via an episomal covalently closed circular DNA (cccDNA) that serves as the transcriptional template for viral mRNAs. The host protein, CCCTC-binding factor (CTCF), is a key regulator of cellular transcription by maintaining epigenetic boundaries, nucleosome phasing, stabilisation of long-range chromatin loops and directing alternative exon splicing. We previously reported that CTCF binds two conserved motifs within Enhancer I of the HBV genome and represses viral transcription, however, the underlying mechanisms were not identified. We show that CTCF depletion in cells harbouring cccDNA-like HBV molecules and in de novo infected cells resulted in an increase in spliced transcripts, which was most notable in the abundant SP1 spliced transcript. In contrast, depletion of CTCF in cell lines with integrated HBV DNA had no effect on the abundance of viral transcripts and in line with this observation there was limited evidence for CTCF binding to viral integrants, suggesting that CTCF-regulation of HBV transcription is specific to episomal cccDNA. Analysis of HBV chromatin topology by Assay for Transposase Accessible Chromatin Sequencing (ATAC-Seq) revealed an accessible region spanning Enhancers I and II and the basal core promoter (BCP). Mutating the CTCF binding sites within Enhancer I resulted in a dramatic rearrangement of chromatin accessibility where the open chromatin region was no longer detected, indicating loss of the phased nucleosome up- and down-stream of the HBV enhancer/BCP. These data demonstrate that CTCF functions to regulate HBV chromatin conformation and nucleosomal positioning in episomal maintained cccDNA, which has important consequences for HBV transcription regulation.