3D microscopy at the nanoscale reveals unexpected lattice rotations in deformed nickel.

In polycrystalline metals, plastic deformation is accompanied by lattice rotations resulting from dislocation glide. Following these rotations in three dimensions requires nondestructive methods that so far have been limited to grain sizes at the micrometer scale. We tracked the rotations of individual grains in nanograined nickel by using three-dimensional orientation mapping in a transmission electron microscope before and after in situ nanomechanical testing. Many of the larger-size grains underwent unexpected lattice rotations, which we attributed to a reversal of rotation during unloading. This inherent reversible rotation originated from a back stress-driven dislocation slip process that was more active for larger grains. These results provide insights into the fundamental deformation mechanisms of nanograined metals and will help to guide strategies for material design and engineering applications.

Predictors of Non-Transport for Older Adult EMS Patients Encountered for Falls.

BACKGROUND: Emergency medical services (EMS) encounters for falls among older adults have been linked to poor outcomes when the patient is not transported by EMS to a hospital. However, little is known regarding characteristics of this patient population. Our primary objective was to describe characteristics associated with non-transport among older adult EMS patients encountered for falls. METHODS: We performed a national retrospective cross-sectional study of 9-1-1 patient contacts from the 2019 ESO Data Collaborative. We included patients who had 9-1-1 encounters for ground-level falls and were aged 60 years or older. Patients residing in congregate living facilities, interfacility transports, cardiac arrests, and suspected drowning patients were excluded. Potential predictors of non-transport included patient demographics, initial vital signs, who requested 9-1-1 service, incident location, alcohol/substance use, and urbanicity. We used multivariable logistic regression to determine associations between non-transport and potential predictors. RESULTS: We identified 195,204 EMS encounters for older adults who fell in 2019, including 27,563 (14.1%) non-transports. Most patients were female (62.4%), non-Hispanic White (85.4%), and fell at a home or residence (80.4%). Greater odds of non-transport were identified among males (OR 1.37, 95% CI 1.32-1.42) and Hispanic/Latino patients (OR 1.24, 95% CI 1.14-1.35). Older age was associated with greater odds of non-transport compared to patients aged 60-69 years (70-79 [OR 1.42, 95% CI 1.35-1.49], 80-89 [OR 1.51, 95% CI 1.42-1.59], ≥90 [OR 1.45, 95% CI 1.35-1.55]). Patients residing in Census tracts with larger percentages of the population living in poverty had lower odds of non-transport compared to those in areas with ≤5% in poverty (6-15% poverty [OR 0.82, 95% CI 0.78-0.84), 15-25% poverty [OR 0.78, 95% CI 0.73-0.82], and >25% poverty [OR 0.78, 95% CI 0.72-0.84]). CONCLUSION: Males, older age groups, and Hispanic/Latino patients had higher odds of non-transport among this population of community-dwelling adults age 60 or greater. These findings may inform development of future targeted falls-related mobile integrated health or community paramedic services and referrals to community intervention programs. Future work is needed to understand underlying patient and clinician perspectives driving non-transport decisions among these patients to better equip EMS clinicians with tools and information on tailored risk/benefit discussions.

Antivenom Does Not Cause Snakebite Complications, Withholding It Does.

We read with interest the retrospective chart review "Crotalidae Polyvalent Immune Fab and Cost-Effective Management of Hospital Admission for Snakebites" by Bowden, et al. The efficacy of US snake antivenoms has been well established for decades. A randomized double-blind placebo-controlled clinical trial (RCT) has demonstrated Fab antivenom efficacy using patient-centered outcomes such as return of functionality and other patient-reported outcomes. These benefits occurred in a predominantly mildly envenomated patient population in a time-dependent manner. The cost-effectiveness of snake antivenom has been demonstrated globally, but no US cost-effectiveness studies have been published. Based on the evidence hierarchy of evidence-based medicine, the discordance between this study and the RCT merits discussion.

Risk of methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) acquisition during ambulance transport: A retrospective propensity-score-matched cohort analysis.

OBJECTIVE: To estimate the relative risk (RR) of developing methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) colonization or infection within 30 days of ambulance transport. METHODS: We performed a retrospective cohort study of patients with a principal diagnosis of chest pain presenting to our emergency department (ED) over a 4-year period. Patients were included if they presented from and were discharged to nonhealthcare locations without being admitted. Encounters were stratified by arrival mechanism: ambulance versus private vehicle. We performed propensity score matching and multivariable logistic regression to estimate the RR for the primary outcome. RESULTS: In total, 321,229 patients had ED encounters during the study period. After applying inclusion criteria and propensity score matching, there were 11,324 patients: 3,903 in the ambulance group and 7,421 in the unexposed group. Among them, 12 patients (0.11%) had the outcome of interest, including 9 (0.08%) with MRSA and 3 (0.03%) with VRE. The 30-day prevalence of MRSA or VRE was larger in the ambulance group than in the unexposed group: 8 (0.20%) and 4 (0.05%), respectively (P = .02). Patients who presented to the ED via ambulance were almost 4 times more likely to have MRSA or VRE within 30 days of their encounter (RR, 3.72; 95% CI, 1.09-12.71; P = .04). CONCLUSIONS: Our cohort study is the first to demonstrate an association between ambulance exposure and pathogen incidence, representing the first step in evaluating medical-transport-associated infection burden to eventually develop interventions to address it.

Increase in COVID-19 inpatient survival following detection of Thromboembolic and Cytokine storm risk from the point of admission to hospital by a near real time Traffic-light System (TraCe-Tic)

Abstract Introduction Our goal was to evaluate if traffic-light driven personalized care for COVID-19 was associated with improved survival in acute hospital settings. Methods Discharge outcomes were evaluated before and after prospective implementation of a real-time dashboard with feedback to ward-based clinicians. Thromboembolism categories were "medium-risk" (D-dimer >1000 ng/mL or CRP >200 mg/L); "high-risk" (D-dimer >3000 ng/mL or CRP >250 mg/L) or "suspected" (D-dimer >5000 ng/mL). Cytokine storm risk was categorized by ferritin. Results 939/1039 COVID-19 positive patients (median age 67 years, 563/939 (60%) male) completed hospital encounters to death or discharge by 21st May 2020. Thromboembolism flag criteria were reached by 568/939 (60.5%), including 238/275 (86.6%) of the patients who died, and 330/664 (49.7%) of the patients who survived to discharge, p < 0.0001. Cytokine storm flag criteria were reached by 212 (22.6%) of admissions, including 80/275 (29.1%) of the patients who died, and 132/664 (19.9%) of the patients who survived, p < 0.0001. The maximum thromboembolism flag discriminated completed encounter mortality (no flag: 37/371 [9.97%] died; medium-risk: 68/239 [28.5%]; high-risk: 105/205 [51.2%]; and suspected thromboembolism: 65/124 [52.4%], p < 0.0001). Flag criteria were reached by 535 consecutive COVID-19 positive patients whose hospital encounter completed before traffic-light introduction: 173/535 (32.3% [95% confidence intervals 28.0, 36.0]) died. For the 200 consecutive admissions after implementation of real-time traffic light flags, 46/200 (23.0% [95% confidence intervals 17.1, 28.9]) died, p = 0.013. Adjusted for age and sex, the probability of death was 0.33 (95% confidence intervals 0.30, 0.37) before traffic light implementation, 0.22 (0.17, 0.27) after implementation, p < 0.001. In subgroup analyses, older patients, males, and patients with hypertension (p ≤ 0.01), and/or diabetes (p = 0.05) derived the greatest benefit from admission under the traffic light system. Conclusion Personalized early interventions were associated with a 33% reduction in early mortality. We suggest benefit predominantly resulted from early triggers to review/enhance anticoagulation management, without exposing lower-risk patients to potential risks of full anticoagulation therapy.

Increase in COVID-19 inpatient survival following detection of Thromboembolic and Cytokine storm risk from the point of admission to hospital by a near real time Traffic-light System (TraCe-Tic).

INTRODUCTION: Our goal was to evaluate if traffic-light driven personalized care for COVID-19 was associated with improved survival in acute hospital settings. METHODS: Discharge outcomes were evaluated before and after prospective implementation of a real-time dashboard with feedback to ward-based clinicians. Thromboembolism categories were "medium-risk" (D-dimer >1000ng/mL or CRP >200mg/L); "high-risk" (D-dimer >3000ng/mL or CRP >250mg/L) or "suspected" (D-dimer >5000ng/mL). Cytokine storm risk was categorized by ferritin. RESULTS: 939/1039 COVID-19 positive patients (median age 67 years, 563/939 (60%) male) completed hospital encounters to death or discharge by 21st May 2020. Thromboembolism flag criteria were reached by 568/939 (60.5%), including 238/275 (86.6%) of the patients who died, and 330/664 (49.7%) of the patients who survived to discharge, p<0.0001. Cytokine storm flag criteria were reached by 212 (22.6%) of admissions, including 80/275 (29.1%) of the patients who died, and 132/664 (19.9%) of the patients who survived, p<0.0001. The maximum thromboembolism flag discriminated completed encounter mortality (no flag: 37/371 [9.97%] died; medium-risk: 68/239 [28.5%]; high-risk: 105/205 [51.2%]; and suspected thromboembolism: 65/124 [52.4%], p<0.0001). Flag criteria were reached by 535 consecutive COVID-19 positive patients whose hospital encounter completed before traffic-light introduction: 173/535 (32.3% [95% confidence intervals 28.0, 36.0]) died. For the 200 consecutive admissions after implementation of real-time traffic light flags, 46/200 (23.0% [95% confidence intervals 17.1, 28.9]) died, p=0.013. Adjusted for age and sex, the probability of death was 0.33 (95% confidence intervals 0.30, 0.37) before traffic light implementation, 0.22 (0.17, 0.27) after implementation, p<0.001. In subgroup analyses, older patients, males, and patients with hypertension (p≤0.01), and/or diabetes (p=0.05) derived the greatest benefit from admission under the traffic light system. CONCLUSION: Personalized early interventions were associated with a 33% reduction in early mortality. We suggest benefit predominantly resulted from early triggers to review/enhance anticoagulation management, without exposing lower-risk patients to potential risks of full anticoagulation therapy.

Visceral leishmaniasis presenting as haemophagocytic lymphohistiocytosis.

A 53-year-old man presented with a number of hospital admissions for investigation of fever of unknown origin. He became gradually weaker with significant weight loss, pancytopenia and progressive splenomegaly over a 6-month period of extensive investigation. This was undertaken at different NHS hospitals with involvement of multiple medical specialists. Clinical criteria for haemophagocytic lymphohistiocytosis were met. Following investigation, this was felt likely secondary to a low-grade lymphoma of the spleen, necessitating splenectomy for diagnostic and therapeutic purposes. Ultimately, this risky surgical procedure was avoided when positive L eishmania serology led to successful treatment with amphotericin B.

Corneal oedema in a unilateral corneal graft patient induced by high Dk mini-scleral contact lens.

INTRODUCTION: Scleral contact lenses are increasingly becoming accepted as the method of choice for visual correction of the irregular cornea. As such, cases have surfaced which demonstrate complications arising from mini-scleral lenses. Identification of these issues and adjusting fitting techniques accordingly is necessary for reducing the risks associated with mini-scleral lens wear. CASE REPORT: A 58 year old Caucasian female was referred for rigid gas permeable contact lens fitting for correction of right irregular astigmatism post penetrating keratoplasty. After four months of successful mini-scleral contact lens wear, the patient experienced a graft rejection episode and treated accordingly, then refit with a new mini-scleral lens. Five months after the lens refit, the patient presented with complaints of hazy vision, and a diagnosis of lens-induced corneal oedema made. DISCUSSION: Increased awareness of the potential complications of mini-scleral lenses is necessary to encourage and enforce mini-scleral lens fitting techniques that meet the requirements of minimum vault but adequate protection of the compromised cornea.

Direct observation of nucleation in the bulk of an opaque sample.

Remarkably little is known about the physical phenomena leading to nucleation of new perfect crystals within deformed metals during annealing, in particular how and where volumes with nearly perfect lattices evolve from structures filled with dislocations, and how local variations at the micrometer length scale affect this nucleation process. We present here the first experimental measurements that relate directly nucleation of recrystallization to the local deformation microstructure in the bulk of a sample of cold rolled aluminum, further deformed locally by a hardness indentation. White beam differential aperture X-ray microscopy is used for the measurements, allowing us to map a selected gauge volume in the bulk of the sample in the deformed state, then anneal the sample and map the exact same gauge volume in the annealed state. It is found that nuclei develop at sites of high stored energy and they have crystallographic orientations from those present in the deformed state. Accordingly we suggest that for each nucleus the embryonic volume arises from a structural element contained within the voxels identified with the same orientation. Possible nucleation mechanisms are discussed and the growth potentials of the nuclei are also analyzed and discussed.

Using routinely gathered data to empower locally led health improvements.

Data are routinely used throughout the NHS to report on and monitor performance. For example, detailed information regarding hospital episodes is reported via the Secondary Use Services (SUS) programme. Local commissioners use this data to monitor hospital contracts. In primary care, data such as glycaemic control of diabetes patients is extracted from general practice clinical systems to calculate practice payments for the 'Quality and Outcomes Framework' (QOF). We suggest that this routinely gathered data should also be used to help clusters of practices to learn from locally led innovation and to motivate long-term partnerships for interorganisational health improvement. Following the recent NHS reforms, the number of data sources that could facilitate this is likely to increase in size, variety and complexity. In this paper, we describe some of the existing data sources that could be used to do this; we also describe some of the dangers of using data in this way, and our conclusions about the best way forward.

Pyruvate kinase M2 is a novel diagnostic marker and predicts tumor progression in human biliary tract cancer.

BACKGROUND: The early diagnosis of biliary tract cancer (BTC) remains challenging, and there are few effective therapies. This study investigated whether the M2 isotype of pyruvate kinase (M2-PK), which serves as the key regulator of cellular energy metabolism in proliferating cells, could play a role in the diagnosis and therapy of BTC. METHODS: Plasma and bile M2-PK concentrations were measured by enzyme-linked immunosorbent assay in 88 patients with BTC, 79 with benign biliary diseases, and 17 healthy controls. M2-PK expression was assayed in a BTC tissue array by immunohistochemistry. The role of M2-PK in tumor growth, invasion, and angiogenesis was evaluated in BTC cell lines by retrovirus-mediated M2-PK transfection and short hairpin RNA silencing techniques. RESULTS: Sensitivity (90.3%) and specificity (84.3%) of bile M2-PK for malignancy were significantly higher than those for plasma M2-PK and serum carbohydrate antigen 19-9. M2-PK expression was specific for cancer cells and correlated with microvessel density. M2-PK positivity was a significant independent prognostic factor by multivariable analysis. Transfection of M2-PK in a negatively expressed cell line (HuCCT-1 cells) increased cell invasion, whereas silencing in an M2-PK-positive cell line (TFK cells) decreased tumor nodule formation and cellular invasion. A significant increase in endothelial tube formation was noted when supernatants from M2-PK-transfected cells were added to an in vitro angiogenesis assay, whereas supernatants from silenced cells negated endothelial tube formation. CONCLUSIONS: Bile M2-PK is a novel tumor marker for BTC and correlates with tumor aggressiveness and poor outcome. Short hairpin RNA-mediated inhibition of M2-PK indicates the potential of M2-PK as a therapeutic target.

Novel N-linked aminopiperidine inhibitors of bacterial topoisomerase type II with reduced pK(a): antibacterial agents with an improved safety profile.

Novel non-fluoroquinolone inhibitors of bacterial type II topoisomerases (DNA gyrase and topoisomerase IV) are of interest for the development of new antibacterial agents that are not impacted by target-mediated cross-resistance with fluoroquinolones. N-Linked amino piperidines, such as 7a, generally show potent antibacterial activity, including against quinolone-resistant isolates, but suffer from hERG inhibition (IC(50) = 44 µM for 7a) and QT prolongation in vivo. We now disclose the finding that new analogues of 7a with reduced pK(a) due to substitution with an electron-withdrawing substituent in the piperidine moiety, such as R,S-7c, retained the Gram-positive activity of 7a but showed significantly less hERG inhibition (IC(50) = 233 µM for R,S-7c). This compound exhibited moderate clearance in dog, promising efficacy against a MRSA strain in a mouse infection model, and an improved in vivo QT profile as measured in a guinea pig in vivo model. As a result of its promising activity, R,S-7c was advanced into phase I clinical studies.

Using routinely gathered data to empower locally led health improvements.

Data are routinely used throughout the NHS to report on and monitor performance. For example, detailed information regarding hospital episodes is reported via the Secondary Use Services (SUS) programme. Local commissioners use this data to monitor hospital contracts. In primary care, data such as glycaemic control of diabetes patients is extracted from general practice clinical systems to calculate practice payments for the 'Quality and Outcomes Framework' (QOF). We suggest that this routinely gathered data should also be used to help clusters of practices to learn from locally led innovation and to motivate long-term partnerships for interorganisational health improvement. Following the recent NHS reforms, the number of data sources that could facilitate this is likely to increase in size, variety and complexity. In this paper, we describe some of the existing data sources that could be used to do this; we also describe some of the dangers of using data in this way, and our conclusions about the best way forward.

The preparation of (-)-grandisine B from (+)-grandisine D; a biomimetic total synthesis or formation of an isolation artefact?

An efficient new alkyne-acetal cyclization procedure has been developed to prepare enantiopure indolizidine building blocks from l-proline and then applied to prepare the Elaeocarpus-derived alkaloids grandisine B and grandisine D in an efficient manner. However, evidence is presented which indicates that grandisine B does not occur naturally but is formed by reaction of grandisine D with ammonia during the extraction/purification process.

Efficacy of loco-regional ablation therapy of HCC in a population of liver transplanted patients.

BACKGROUND AND OBJECTIVE: Loco-ablation therapy (LAT) has become standard treatment for patients with HCC who are candidates for liver transplantation (LT). The aim of this study was: to evaluate if LAT was able to induce complete necrosis of tumour mass; to determine the tumour recurrence rate after LT and factors associated with recurrence. PATIENTS: The percentage and the distribution of necrosis in 116 HCC nodules of 61 patients with (26 patients) and without (35 patients) previous types of LAT were examined in explanted livers. RESULTS: Total necrosis was found only in 7% of treated nodules, and 42% of these showed absence of necrosis. The amount of necrosis was significantly related to the gross appearance of HCC: a single nodule with smaller adjacent satellite nodules showed a higher percentage of necrosis. No relation was found between the amount of necrosis and the type of LAT. Recurrence was observed in 11.5% and 8.5% of patients with and without previous LAT, respectively (P = ns). CONCLUSIONS: LAT very rarely induces complete necrosis; the amount of necrosis seems to depend on the growth pattern of the tumour and not on the type of previous LAT; the tumour size, measured at explant, is the only variable significantly related to recurrence.

Lentiviral manipulation of gene expression in human adult and embryonic stem cells.

Human stem cells could revolutionize the field of medicine by providing a diverse range of cell types for tissue replacement therapies and drug discovery. To achieve this goal, genetic tools need to be optimized and developed for controlling and manipulating stem cells ex vivo. Here we describe a lentiviral delivery system capable of high infection rates in human mesenchymal and embryonic stem cells. The lentiviral backbone was modified to express mono- and bi-cistronic transgenes and was also used to deliver short hairpin ribonucleic acid for specific silencing of gene expression in human stem cells. We show that lentiviral transduction can be used to alter gene expression without altering the genes' ability to differentiate in vitro. These vectors will enable rapid analysis of gene function in stem cells and permit the generation of knock-in / knock-out models of human disease in the rapidly developing field of gene therapy.

Mitochondria as signaling organelles in the vascular endothelium.

Vascular endothelial cells are highly glycolytic and consume relatively low amounts of oxygen (O(2)) compared with other cells. We have confirmed that oxidative phosphorylation is not the main source of ATP generation in these cells. We also show that at a low O(2) concentration (<1%) endogenous NO plays a key role in preventing the accumulation of the alpha-subunit of hypoxia-inducible factor 1. At higher O(2) concentrations (1-3%) NO facilitates the production of mitochondrial reactive oxygen species. This production activates the AMP-activated protein kinase by a mechanism independent of nucleotide concentrations. Thus, the primary role of mitochondria in vascular endothelial cells may not be to generate ATP but, under the control of NO, to act as signaling organelles using either O(2) or O(2)-derived species as signaling molecules. Diversion of O(2) away from endothelial cell mitochondria by NO might also facilitate oxygenation of vascular smooth muscle cells.

Inhibiting primary effusion lymphoma by lentiviral vectors encoding short hairpin RNA.

We use lentiviral-delivered RNA interference (RNAi) to inhibit the growth of a model of primary effusion lymphoma (PEL) in vitro and in vivo. RNAi is a phenomenon allowing the sequence-specific targeting and silencing of exogenous and endogenous gene expression and is being applied to inhibit viral replication both in vitro and in vivo. We show that silencing of genes believed to be essential for the Kaposi sarcoma-associated herpesvirus (KSHV) latent life cycle (the oncogenic cluster) has a varied effect in PEL cell lines cultured in vitro, however, concomitant silencing of the viral cyclin (vcyclin) and viral FLICE (Fas-associating protein with death domain-like interleukin-1beta-converting enzyme) inhibitory protein (vFLIP) caused efficient apoptosis in all PEL lines tested. We demonstrate that in a murine model of PEL, lentiviral-mediated RNA interference both inhibits development of ascites and can act as a treatment for established ascites. We also show that the administered lentiviral vectors are essentially limited to the peritoneal cavity, which has advantages for safety and dosage in a therapeutic setting. This shows the use of lentiviral-mediated RNA interference in vivo as a potential therapeutic against a virally driven human cancer.

RNA interference: a potential tool against Kaposi's sarcoma-associated herpesvirus.

PURPOSE OF REVIEW: RNA interference is a conserved cellular function that controls viral infection, the expression of transposable elements, repetitive sequences and genes in embryonic development. Originally described as an antiviral mechanism in plants, known as posttranscriptional gene silencing, it is now appreciated that this phenomenon occurs in all living cells. Double-stranded RNA, when acting as part of RNA interference, reduces expression of genes with sequence similarity, but has no effect on the expression of genes of unrelated sequence. Studies of RNA interference in mammalian cells have demonstrated that exogenous genes delivered by DNA transfection as well as endogenous gene expression can be suppressed by the delivery of RNA interference. We discuss here the potential for exploiting this phenomenon to prevent or treat viral infections, in particular Kaposi's sarcoma-associated herpesvirus. RECENT FINDINGS: There have been several studies showing that RNA interference can be exploited to target a wide range of human viruses, including HIV-1, human T cell leukaemia virus-1, human papillomavirus, hepatitis B, hepatitis C and the polio virus. RNA interference is effective in mammalian cells and can be delivered by various methods. Double-stranded RNA has been injected into the tail veins of mice to block both virally and chemically induced hepatitis. SUMMARY: A greater understanding of RNA interference allows us to exploit this phenomenon in order to study the functions of genes in mammalian cells, and also to target the expression of mutated cellular or viral genes. New delivery techniques should be developed to allow the process to be used as a therapeutic tool against viruses and malignancies in humans.