macroH2A1 drives nucleosome dephasing and genome instability in histone humanized yeast.

In addition to replicative histones, eukaryotic genomes encode a repertoire of non-replicative variant histones, providing additional layers of structural and epigenetic regulation. Here, we systematically replace individual replicative human histones with non-replicative human variant histones using a histone replacement system in yeast. We show that variants H2A.J, TsH2B, and H3.5 complement their respective replicative counterparts. However, macroH2A1 fails to complement, and its overexpression is toxic in yeast, negatively interacting with yeast's native histones and kinetochore genes. To isolate yeast with macroH2A1 chromatin, we uncouple the effects of its macro and histone fold domains, revealing that both domains suffice to override native nucleosome positioning. Furthermore, both uncoupled constructs of macroH2A1 exhibit lower nucleosome occupancy, decreased short-range chromatin interactions (<20 kb), disrupted centromeric clustering, and increased chromosome instability. Our observations demonstrate that lack of a canonical histone H2A dramatically alters chromatin organization in yeast, leading to genome instability and substantial fitness defects.

Update of biomarkers to diagnose diabetic foot osteomyelitis: A meta-analysis and systematic review.

The aim of this study was to evaluate the diagnostic characteristics of biomarker for diabetic foot osteomyelitis (DFO). We searched PubMed, Scopus, Embase and Medline for studies who report serological markers and DFO before December 2022. Studies must include at least one of the following diagnostic parameters for biomarkers: area under the curve, sensitivities, specificities, positive predictive value, negative predictive value. Two authors evaluated quality using the Quality Assessment of Diagnostic Accuracy Studies tool. We included 19 papers. In this systematic review, there were 2854 subjects with 2134 (74.8%) of those patients being included in the meta-analysis. The most common biomarkers were erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and procalcitonin (PCT). A meta-analysis was then performed where data were evaluated with Forrest plots and receiver operating characteristic curves. The pooled sensitivity and specificity were 0.72 and 0.75 for PCT, 0.72 and 0.76 for CRP and 0.70 and 0.77 for ESR. Pooled area under the curves for ESR, CRP and PCT were 0.83, 0.77 and 0.71, respectfully. Average diagnostic odds ratios were 16.1 (range 3.6-55.4), 14.3 (range 2.7-48.7) and 6.7 (range 3.6-10.4) for ESR, CRP and PCT, respectfully. None of the biomarkers we evaluated could be rated as 'outstanding' to diagnose osteomyelitis. Based on the areas under the curve, ESR is an 'excellent' biomarker to detect osteomyelitis, and CRP and PCT are 'acceptable' biomarkers to diagnose osteomyelitis. Diagnostic odds ratios indicate that ESR, CRP and PCT are 'good' or 'very good' tools to identify osteomyelitis.

Success of transmetatarsal amputation for limb salvage in patients with peripheral artery disease.

Limb salvage is a difficult path for patients to travel as there is no guarantee of the outcome, often the major factor is perfusion. For patients who underwent transmetatarsal amputation (TMA), success rate is crucial as the next option is most likely a major amputation. We performed a 10 years (2010-2020) retrospective review of patients that underwent a TMA and had an angiogram or computed tomography angiography (CTA) perioperatively at the Dallas VA Medical Center. Failure after TMA was defined as a patient requiring a proximal amputation within 1 year. There were 125 TMAs performed between 2010 and 2020 at the institution. Forty-four (35.2%) patients had an angiogram/CTA peri-operative and met the inclusion criteria. Seventeen subjects (38.6%) had a higher level of amputation. Of the 17 failures, 2 (11.8%) patients had no patent vessel runoff to the foot, 9 (52.9%) had one vessel, 4 (23.5%) had two vessels, and 2 (11.8%) had three vessels runoff. One vessel runoff to the foot yielded a high rate of poor outcomes (56.3%) defined as a higher level of amputation. Two or more vessels runoff to the foot had over 75% success of limb salvage with a TMA.

Does antibiotic treatment before bone biopsy affect the identification of bacterial pathogens from bone culture?

There is a common belief and practice that any exposure to oral or parenteral antibiotics prior to bone biopsy makes culture results unreliable. The aim of this article was to evaluate the effect of antibiotic exposure on bacterial yield in DFO microbiology specimens. The authors retrospectively evaluated 114 patients with DFO confirmed by histology. The primary outcome measurement was the proportion of bone biopsies with positive bacterial cultures. There was no statistically significant difference in culture yield in patients who received antibiotics (77.9%) and patients who did not (85.7%, P = .58). This study demonstrates that there were no differences in bacterial yield whether antibiotics were withheld or administered before bone cultures were obtained. The duration of antibiotic use prior to bone biopsy did not change the bacterial yield.

Human macroH2A1 drives nucleosome dephasing and genome instability in histone-humanized yeast.

In addition to replicative histones, eukaryotic genomes encode a repertoire of non-replicative variant histones providing additional layers of structural and epigenetic regulation. Here, we systematically replaced individual replicative human histones with non-replicative human variant histones using a histone replacement system in yeast. Variants H2A.J, TsH2B, and H3.5 complemented for their respective replicative counterparts. However, macroH2A1 failed to complement and its expression was toxic in yeast, negatively interacting with native yeast histones and kinetochore genes. To isolate yeast with "macroH2A1 chromatin" we decoupled the effects of its macro and histone fold domains, which revealed that both domains sufficed to override native yeast nucleosome positioning. Furthermore, both modified constructs of macroH2A1 exhibited lower nucleosome occupancy that correlated with decreased short-range chromatin interactions (<20 Kb), disrupted centromeric clustering, and increased chromosome instability. While supporting viability, macroH2A1 dramatically alters chromatin organization in yeast, leading to genome instability and massive fitness defects.

DASH/Dam1 complex mutants stabilize ploidy in histone-humanized yeast by weakening kinetochore-microtubule attachments.

Forcing budding yeast to chromatinize their DNA with human histones manifests an abrupt fitness cost. We previously proposed chromosomal aneuploidy and missense mutations as two potential modes of adaptation to histone humanization. Here, we show that aneuploidy in histone-humanized yeasts is specific to a subset of chromosomes that are defined by their centromeric evolutionary origins but that these aneuploidies are not adaptive. Instead, we find that a set of missense mutations in outer kinetochore proteins drives adaptation to human histones. Furthermore, we characterize the molecular mechanism underlying adaptation in two mutants of the outer kinetochore DASH/Dam1 complex, which reduce aneuploidy by suppression of chromosome instability. Molecular modeling and biochemical experiments show that these two mutants likely disrupt a conserved oligomerization interface thereby weakening microtubule attachments. We propose a model through which weakened microtubule attachments promote increased kinetochore-microtubule turnover and thus suppress chromosome instability. In sum, our data show how a set of point mutations evolved in histone-humanized yeasts to counterbalance human histone-induced chromosomal instability through weakening microtubule interactions, eventually promoting a return to euploidy.

High-Risk Patients with Infected Puncture Wounds and Appropriate Tetanus Prophylaxis.

BACKGROUND: We sought to evaluate clinicians' compliance with national guidelines for tetanus vaccination prophylaxis in patients with high-risk feet. METHODS: We retrospectively evaluated 114 consecutive patients between June 1, 2011, and March 31, 2019, who presented to the emergency department with a foot infection resulting from a puncture injury. Eighty-three patients had diabetes mellitus and 31 patients did not have diabetes mellitus. Electronic medical records were used to collect a broad range of study data on patient demographics, medical history, tetanus immunization history and tetanus status on presentation to the emergency department, peripheral arterial disease, sensory neuropathy, laboratory values, and clinical/surgical outcomes. RESULTS: Of the 114 patients who presented to the emergency department with a puncture wound, 53 (46.5%) did not have up-to-date tetanus immunization. Of those patients, 79.2% received a tetanus-containing vaccine booster, 3.8% received intramuscular tetanus immunoglobulin, 3.8% received both a tetanus-containing vaccine booster and tetanus immunoglobulins, and 20.8% received no form of tetanus prophylaxis. Comparing data between patients with and without diabetes mellitus, there were no statistically significant differences in tetanus prophylaxis. CONCLUSIONS: Guidelines for tetanus prophylaxis among high-risk podiatric medical patients in this study center are not followed in all patients. Patients with diabetes mellitus are at high risk for exposure to tetanus; therefore, we recommend that physicians take a detailed tetanus immunization history and vaccinate patients if the tetanus history is unclear.

Brief Report: Effect of Antiretroviral Switch From Tenofovir Disoproxil fumarate to Tenofovir Alafenamide on Alanine Aminotransferase, Lipid Profiles, and Renal Function in HIV/HBV-Coinfected Individuals in a Nationwide Canadian Study.

OBJECTIVE: Tenofovir alafenamide (TAF) achieves increased renal safety and improved alanine aminotransferase (ALT) normalization but increased lipid profile in hepatitis B virus (HBV)-monoinfected patients switched from tenofovir disoproxil fumarate (TDF). It is unclear whether HIV coinfection perturbs these biochemical changes. To this end, we assessed these parameters in HIV/HBV-coinfected patients switched from TDF to TAF. DESIGN: Retrospective, multicenter, observational study. METHODS: HIV/HBV-coinfected patients switched from TDF to TAF-based antiretroviral therapy (ART) at 6 Canadian Hepatitis B Network (CanHepB) academic sites were included. Changes in lipid profile, estimated glomerular filtration rate (eGFR), and ALT were evaluated using linear mixed effect model regression. RESULTS: Eighty-two HIV/HBV-coinfected patients with a mean 103-week follow-up duration were identified. At time of TAF switch, 80 of 82 (98%) were HBV virally suppressed, 29 of 82 (35%) had elevated ALT levels, and 63 of 82 (77%) had eGFR of ≥60 mL/min per 1.73 m 2 . Twenty-six/Eighty-two (32%) had preexisting renal comorbidities. There were no changes in total cholesterol, high-density lipoprotein, low-density lipoprotein, and triglyceride levels 2 years after TAF switch. Those with elevated ALT levels achieved greater ALT normalization after TAF switch (-0.004 [-0.008 to 0.0] log 10 U/L/mo, P = 0.03). eGFR decline rate while on TDF (-0.66 [-0.23 to -1.08] mL/min/month, P < 0.005) was diminished after switching to TAF (-0.02 [-0.16 to 0.11] mL/min/mo, P = 0.7) and those with eGFR of <60 mL/min experienced increase in eGFR after TAF switch (0.45 [0.03-0.87] mL/min/mo, P = 0.04). CONCLUSIONS: Our study supports switching from TDF to TAF with positive influence on overall long-term biochemical profile in HIV/HBV-coinfected individuals.

Nationwide retrospective study of hepatitis B virological response and liver stiffness improvement in 465 patients on nucleos(t)ide analogue.

BACKGROUND: Hepatitis B virus (HBV) nucleos(t)ide analog (NA) therapy reduces liver disease but requires prolonged therapy to achieve hepatitis B surface antigen (HBsAg) loss. There is limited North American real-world data using non-invasive tools for fibrosis assessment and few have compared 1st generation NA or lamivudine (LAM) to tenofovir disoproxil fumarate (TDF). AIM: To assess impact of NA on virological response and fibrosis regression using liver stiffness measurement (LSM) (i.e., FibroScan®). METHODS: Retrospective, observational cohort study from the Canadian HBV Network. Data collected included demographics, NA, HBV DNA, alanine aminotransferase (ALT), and LSM. Patients were HBV monoinfected patients, treatment naïve, and received 1 NA with minimum 1 year follow-up. RESULTS: In 465 (median 49 years, 37% female, 35% hepatitis B e antigen+ at baseline, 84% Asian, 6% White, and 9% Black). Percentage of 64 (n = 299) received TDF and 166 were LAM-treated with similar median duration of 3.9 and 3.7 years, respectively. The mean baseline LSM was 11.2 kPa (TDF) vs 8.3 kPa (LAM) (P = 0.003). At 5-year follow-up, the mean LSM was 7.0 kPa in TDF vs 6.7 kPa in LAM (P = 0.83). There was a significant difference in fibrosis regression between groups (i.e., mean -4.2 kPa change in TDF and -1.6 kPa in LAM, P < 0.05). The last available data on treatment showed that all had normal ALT, but more TDF patients were virologically suppressed (< 10 IU/mL) (n = 170/190, 89%) vs LAM-treated (n = 35/58, 60%) (P < 0.05). None cleared HBsAg. CONCLUSION: In this real-world North American study, approximately 5 years of NA achieves liver fibrosis regression rarely leads to HBsAg loss.

Meta-Analysis: Outcomes of Surgical and Medical Management of Diabetic Foot Osteomyelitis.

Background: The aim of this study was to evaluate clinical outcomes in the published literature on medical and surgical management of diabetic foot osteomyelitis (DFO). Methods: A PubMed and Google Scholar search of articles relating to DFO was performed over the dates of January 1931 to January 2020. Articles that involved Charcot arthropathy, case reports, small case series, review articles, commentaries, nonhuman studies, and non-English articles were excluded. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used to rate the bias of each study. A meta-analysis was performed using random-effects and inverse variance methods. The search yielded 1192 articles. After review and the removal of articles that did not meet inclusion criteria, 28 articles remained. Eighteen articles were related to the medical management of DFO and 13 articles were related to surgical management. Three articles looked at a combination of medical and surgical management and were included in both groups. Heterogeneity was evaluated using Cochran Q, I 2, τ2, and τ. Results: The average success rate was 68.2% (range, 17.0%-97.3%) for medical treatment and 85.7% (range, 65.0%-98.8%) for surgical and medical treatment. There were significant inconsistencies in accounting for peripheral arterial disease and peripheral neuropathy. There was significant heterogeneity in outcomes between studies. However, there was a high rate of successful treatment and a wide range between patients with medical treatment and combined surgical and medical treatment. Conclusions: Additional properly designed prospective studies with gold-standard references for diagnosing osteomyelitis are needed to help determine whether medical management of DFO can be successful without surgical intervention.

A Comparison of Pathogens in Skin and Soft-Tissue Infections and Pedal Osteomyelitis in Puncture Wound Injuries Affecting the Foot.

BACKGROUND: To compare pathogens involved in skin and soft-tissue infections (SSTIs) and pedal osteomyelitis (OM) in patients with and without diabetes with puncture wounds to the foot. METHODS: We evaluated 113 consecutive patients between June 1, 2011, and March 31, 2019, with foot infection (SSTIs and OM) from a puncture injury sustained to the foot. Eighty-three patients had diabetes and 30 did not. We evaluated the bacterial pathogens in patients with SSTIs and pedal OM. RESULTS: Polymicrobial infections were more common in patients with diabetes mellitus (83.1% versus 53.3%; P = .001). The most common pathogen for SSTIs and OM in patients with diabetes was Staphylococcus aureus (SSTIs, 50.7%; OM, 32.3%), whereas in patients without diabetes it was Pseudomonas (25%) for SSTIs. Anaerobes (9.4%) and fungal infection (3.1%) were uncommon. Pseudomonas aeruginosa was identified in only 5.8% of people with diabetes. CONCLUSIONS: The most common bacterial pathogen in both SSTIs and pedal OM was S aureus in patients with diabetes. Pseudomonas species was the most common pathogen in people without diabetes with SSTIs.

The Impact of Hospitalization for Diabetic Foot Infection on Health-Related Quality of Life: Utilizing PROMIS.

Diabetic foot infections (DFI) are an increasingly common cause of hospitalizations. Once hospitalized with DFI, many patients require some level of amputation, often undergoing multiple operations. With increasing importance on patient-centered metrics, self-reported health-related quality of life (HRQOL) tools have been developed. This prospective cohort study aimed assessed the impact of DFI on HRQOL. Two hundred twenty-four patients completed the 29-item Patient-Reported Outcome Measurement Information System (PROMIS) and 12-Item Short Form (SF-12) survey. Secondary outcomes using the Foot and Ankle Ability Measures survey were obtained and included in the analysis. The study group was comprised of hospitalized patients with DFIs (n = 120), and the control group was comprised of patients with diabetes who were evaluated for routine outpatient foot care (n = 104); diabetic foot screening, wound care, onychomycosis, and/or callosities. Using this cohort, a propensity score-matched sample of hospitalized patients with DFI (n = 35) and control group patients (n = 35) was created for comparative analysis. The 2-independent sample t test was used to test for group differences on each of the PROMIS subscale outcomes. Using PROMIS, we found that hospitalized patients with DFI reported significantly worse HRQOL in 6 of 7 subscales (physical function, anxiety, depression, fatigue, social role, pain intensity; p value range: .0001-.02) compared to outpatients with diabetes evaluated for routine foot care. There was no significant difference between the 2 groups on sleep disturbance (p = .22). Patients hospitalized for DFI report lower HRQOL compared to patients with diabetes receiving routine outpatient foot care.

A versatile platform for locus-scale genome rewriting and verification.

Routine rewriting of loci associated with human traits and diseases would facilitate their functional analysis. However, existing DNA integration approaches are limited in terms of scalability and portability across genomic loci and cellular contexts. We describe Big-IN, a versatile platform for targeted integration of large DNAs into mammalian cells. CRISPR/Cas9-mediated targeting of a landing pad enables subsequent recombinase-mediated delivery of variant payloads and efficient positive/negative selection for correct clones in mammalian stem cells. We demonstrate integration of constructs up to 143 kb, and an approach for one-step scarless delivery. We developed a staged pipeline combining PCR genotyping and targeted capture sequencing for economical and comprehensive verification of engineered stem cells. Our approach should enable combinatorial interrogation of genomic functional elements and systematic locus-scale analysis of genome function.

Regulation of the Dot1 histone H3K79 methyltransferase by histone H4K16 acetylation.

Dot1 (disruptor of telomeric silencing-1), the histone H3 lysine 79 (H3K79) methyltransferase, is conserved throughout evolution, and its deregulation is found in human leukemias. Here, we provide evidence that acetylation of histone H4 allosterically stimulates yeast Dot1 in a manner distinct from but coordinating with histone H2B ubiquitination (H2BUb). We further demonstrate that this stimulatory effect is specific to acetylation of lysine 16 (H4K16ac), a modification central to chromatin structure. We provide a mechanism of this histone cross-talk and show that H4K16ac and H2BUb play crucial roles in H3K79 di- and trimethylation in vitro and in vivo. These data reveal mechanisms that control H3K79 methylation and demonstrate how H4K16ac, H3K79me, and H2BUb function together to regulate gene transcription and gene silencing to ensure optimal maintenance and propagation of an epigenetic state.

Efficacy of Auricular Acupuncture in Chemotherapy-Induced Peripheral Neuropathy: A Case Series of 73 Cases.

Background: Chemotherapy-induced peripheral neuropathy (CIPN) can adversely affect completion of systemic anticancer treatment and cause long-term morbidity. To date, its physiopathology remains unclear, and treatments are rare and poorly performed. Auricular acupuncture has already offered interesting results in several symptoms. Objective: This study (AACIPN2020) assessed the efficacy of auriculotherapy in CIPN. Design: We used patients' systematically collected data of 2014-2016 in a medical oncology practice. The treatment was made according to guidelines of the interuniversity diploma and the cartography of the World Health Organization. Pain assessment according to the Common Terminology Criteria for Adverse Event scale was orally collected. Results: Seventy-three cancer patients were treated for CIPN. They had finished chemotherapy 24 weeks prior on average. They received on average 23 punctures at each appointment. Sixty-five percent of patients met satisfaction, with 31% with a real impact on their daily life. Efficacy appeared after one or two treatments for 96% of cases. Some patients continued treatment to maximize benefits. Conclusions: Auricular acupuncture is a safe and inexpensive method of CIPN treatment. It may be applied earlier in chemotherapy administration, and in a large variety of other symptoms. Clinical trial registration number: COS RGDS 2019 09 001.

Quality of palliative care in identified palliative care beds.

BACKGROUND: Dedicated identified palliative care beds (IPCB) are unique to France. AIMS: This study aimed to assess their use and advantages in a medical oncology department of a private provincial hospital. FINDINGS: Of the last 100 patients who died in the medical oncology department, 57 had an IPCB. Those with an IPCB had a longer final hospital stay and significant advantages for them were access to pain evaluation by nurses and professional psychological support. Opioid use was higher, but not significantly so. There were no significant differences for the presence of close relatives, physiotherapy interventions, social workers or specific anti-cancer treatment in the last 15 days of life. CONCLUSION: This study shows some advantages for IPCB (treatment of pain, psychologist), which should be further explored. The length of the final hospital stay is controversial.

Nonhealing Wounds with Verrucous Presentation in the Neuropathic Patient: A Report of Two Cases.

Verrucous skin lesions on the feet of diabetic patients in conjunction with a neuropathic foot ulcer is an uncommon incident. Currently, there are approximately 20 reported cases in the literature. Herein we report two cases of verrucous lesions superimposing a chronic diabetic ulcer. Patients failed several conservative treatments, and several biopsies were performed with inconclusive results, suggesting possible underlying verrucous carcinoma. Given the possibility of underlying malignancy, both patients were treated with wide excision, and both were negative for malignancy, thus confirming verrucous skin lesions on the feet in diabetic neuropathy. We also summarize the current literature on verrucous skin lesions on the feet in diabetic neuropathy.