Thermodynamics of hybrid quantum rotor devices

We investigate the thermodynamics of a hybrid quantum device consisting of two qubits collectively interacting with a quantum rotor and coupled dissipatively to two equilibrium reservoirs at different temperatures. By modeling the dynamics and the resulting steady state of the system using a collision model, we identify the functioning of the device as a thermal engine, a refrigerator, or an accelerator. In addition, we also look into the device's capacity to operate as a heat rectifier and optimize both the rectification coefficient and the heat flow simultaneously. Drawing an analogy to heat rectification and since we are interested in the conversion of energy into the rotor's kinetic energy, we introduce the concept of angular momentum rectification, which may be employed to control work extraction through an external load.

Active transport nanochelators for the reduction of liver iron burden in iron overload

Liver dysfunction and failure account for a major portion of premature deaths in patients suffering from various iron associated pathogeneses, particularly primary and secondary iron overload disorders, despite intensive treatment. The liver is a central player in iron homeostasis and a major iron storage organ, and currently, there are no active approaches for the excretion of excess liver iron. Herein, we report a new method for the rapid reduction of iron burden in iron overload diseases by developing a new class of liver targeted nanochelators with favorable pharmacokinetics and biodistribution. The new nanochelators bypass the reticuloendothelial system and specifically target hepatocytes without non-specific accumulation in other organs. The targeted nanochelators bound and neutralized excess iron in the liver and from the vasculature and, eventually leading to rapid hepatobiliary excretion of labile iron. Further, these rapidly excreted nanochelators did not induce toxicity in the liver, were highly cytocompatible in both iron overload and non-loaded conditions, and were promising in mitigating iron triggered free radical oxidative damage. These studies provide key insights into the development of organ targeted nanochelating systems and the rapid reduction of iron burden in vivo. This methodology allows for further development of nanotherapeutics for specific iron overload diseases.

Cross-sectional survey on physician burnout during the COVID-19 pandemic in Vancouver, Canada: the role of gender, ethnicity and sexual orientation

OBJECTIVE

To determine the prevalence of physician burnout during the pandemic and differences by gender, ethnicity or sexual orientation.

DESIGN, SETTING AND PARTICIPANTS

We conducted a cross-sectional survey (August-October in 2020) of internal medicine physicians at two academic hospitals in Vancouver, Canada.

PRIMARY AND SECONDARY OUTCOMES

Physician burnout and its components, emotional exhaustion, depersonalisation and personal accomplishment were measured using the Maslach Burnout Inventory.

RESULTS

The response rate was 38% (n=302/803 respondents, 49% women,). The prevalence of burnout was 68% (emotional exhaustion 63%, depersonalisation 39%) and feeling low personal accomplishment 22%. In addition, 21% reported that they were considering quitting the profession or had quit a position. Women were more likely to report emotional exhaustion (OR 2.00, 95% CI: 1.07 to 3.73, p=0.03) and feeling low personal accomplishment (OR 2.26, 95% CI: 1.09 to 4.70, p=0.03) than men. Visible ethnic minority physicians were more likely to report feeling lower personal accomplishment than white physicians (OR 1.81, 95% CI: 1.28 to 2.55, p=0.001). There was no difference in emotional exhaustion or depersonalisation by ethnicity or sexual orientation. Physicians who reported that COVID-19 affected their burnout were more likely to report any burnout (OR: 3.74, 95% CI: 1.99 to 7.01, p<0.001) and consideration of quitting or quit (OR: 3.20, 95% CI: 1.34 to 7.66, p=0.009).

CONCLUSION

Burnout affects 2 out of 3 internal medicine physicians during the pandemic. Women, ethnic minority physicians and those who feel that COVID-19 affects burnout were more likely to report components of burnout. Further understanding of factors driving feelings of low personal accomplishment in women and ethnic minority physicians is needed.

Insufficient evidence exists to use histopathologic subtype to guide treatment of idiopathic multicentric Castleman disease

Idiopathic multicentric Castleman disease (iMCD) is a rare immunologic disorder characterized by systemic inflammation, multicentric lymphadenopathy, and organ dysfunction. Enlarged lymph nodes demonstrate a spectrum of characteristic but variable histopathologic features historically categorized into hyaline vascular (HV) (or hypervascular [HyperV] more recently), plasmacytic, or "mixed." Though the etiology is unknown, a pro-inflammatory cytokine storm, often involving interleukin-6 (IL-6), contributes to pathogenesis. Anti-IL-6 therapy with siltuximab is the only FDA- or EMA-approved treatment based on efficacy and safety in multiple studies. Importantly, no patients considered to have HV histopathology achieved the primary endpoint in the Phase II study. NCCN currently recommends siltuximab first-line for iMCD, except for patients considered to have HV histopathology. We investigated whether histopathologic subtype should guide siltuximab treatment decisions. Secondary analyses of clinical trial and real-world data revealed similar clinical benefit across histopathologic subtypes. Notably, only 18 of 79 patients in the Phase II study were consistently classified into histopathologic subtype by three independent review panels, demonstrating limited reliability to guide treatment decisions. Real-world data further demonstrate siltuximab's effectiveness in patients considered to have HV (or HyperV). Though histopathology is a critical component for diagnosis, there is insufficient evidence to guide treatment based solely on lymph node histopathologic subtype.

Improved survival outcomes with the addition of rituximab to initial therapy for chronic lymphocytic leukemia: a comparative effectiveness analysis in the province of British Columbia, Canada

Chemoimmunotherapy with rituximab improves survival in clinical trials in upfront chronic lymphocytic leukemia (CLL) treatment. This study compared clinical outcomes with and without rituximab added to first-line chemotherapy in a provincial cohort of CLL patients. Between 1973 and 2014, 1345 patients received CLL treatment: 48% with rituximab, 52% chemotherapy alone. Median overall survival (OS) and treatment-free survival (TFS) were significantly longer with rituximab: OS 8.9 vs. 6.2 years, p < .0001; TFS 3.6 vs. 2.1 years, p < .0001. Addition of rituximab to chemotherapy was a strong independent predictor of mortality with a 32% mortality reduction after controlling for co-variates (age, sex, stage, and treatment with purine analogs). This large population-based study complements clinical trial and registry data demonstrating the benefit of adding rituximab to first-line CLL therapy and adds further evidence of the efficacy of rituximab-based chemoimmunotherapy in a real-world setting.

ITACA: A new validated international erythropoietic stimulating agent-response score that further refines the predictive power of previous scoring systems

BACKGROUND

In 'real-life', the Nordic score guides Erythropoietic stimulating agent (ESA) use in lower-risk myelodysplastic syndrome (MDS) with predicted response rates of 25% or 74%. As new treatments emerge, a more discriminating score is needed.

OBJECTIVES

To validate existing ESA predictive scores and develop a new score that identifies non-responders.

METHODS

ESA-treated patients were identified in 3 MDS registries in Italy and Canada (FISM 555, GROM 233, and MDS-CAN 208). Clinical and disease-related variables were captured. Nordic, MDS-CAN, and IPSS-R-based ESA scores were calculated and documented ESA responses compared.

RESULTS

996 ESA-treated patients were identified. Overall response rate (ORR) was 59%. The database was randomly divided into balanced derivation (n = 463) and validation (n = 462) cohorts. By multivariate analysis, transfusion independence, erythropoietin (EPO) level <100 IU/L, and IPSS low-risk were independently predictive of response. Assigning a score of 1 to each resulted in a scoring system of 0-3 with response rates of 23%, 43%, 67%, and 85%. ORR was concordant in the validation cohort. The 'ITACA' score had the highest discriminating power of response.

CONCLUSION

ITACA is an internally-validated predictive SS of ESA response in real-life 'good risk' MDS patients derived from a large international dataset that surpasses others. The incorporation of biologic markers to better identify non-responders is still needed.

Plasmablastic lymphoma in the ano-rectal junction presenting in an immunocompetent man: a case report

Introduction

Plasmablastic lymphoma is an aggressive non-Hodgkin lymphoma classically occurring in individuals infected with HIV. Plasmablastic lymphoma has a predilection for the oral cavity and jaw. However, recent case reports have shown lymphoma in the stomach, lung, nasal cavity, cervical lymph nodes and jejunum in HIV-negative individuals. We report what is, to the best of our knowledge, the first case of plasmablastic lymphoma occurring in the ano-rectal junction of an HIV-negative man.

Case Presentation

A previously healthy 59-year-old Caucasian man presented with painless rectal bleeding. Colonoscopy revealed a lesion in the ano-rectal junction, with pathological examination demonstrating atypical lymphoid cells consisting primarily of plasmablasts with rounded nuclei, coarse chromatin, small nucleoli and multiple mitotic figures. Immunohistochemical analysis showed the atypical cells were negative for CD45, CD20, CD79a and immunoglobulin light chains, but were strongly positive for CD138 and EBV-encoded RNA. The results were consistent with a diagnosis of plasmablastic lymphoma. Aggressive systemic chemotherapy and involved field radiation therapy resulted in complete clinical and pathological remission.

Conclusion

Increasing awareness of plasmablastic lymphoma in HIV-negative individuals and in this location is warranted.

Array comparative genomic hybridization of peripheral blood granulocytes of patients with myelodysplastic syndrome detects karyotypic abnormalities

The diagnosis of myelodysplastic syndromes (MDSs) relies largely on morphologic and karyotypic abnormalities, present in about 50% of patients with MDS. Array-based genomic platforms have identified copy number alterations in 50% to 70% of bone marrow samples of patients with MDS with a normal karyotype, suggesting a diagnostic role for these platforms. We investigated whether blood granulocytes harbor the same copy number alterations as the marrow of affected patients. Of 11 patients, 4 had cytogenetic abnormalities shown by conventional karyotyping involving chromosomes 5, 8, 11, 20, and X, and these changes were seen in the granulocytes of all 4 patients by using array comparative genomic hybridization (aCGH). Cryptic alterations were identified at a significantly higher level in marrow CD34+ cells compared with granulocytes (P < .0001). These data suggest that aCGH analysis of circulating granulocytes may be useful in detecting gross karyotypic alterations in patients with MDS when marrow examination has failed or not been done.

Effect of protease inhibitor-based highly active antiretroviral therapy on survival in HIV-associated advanced Kaposi's sarcoma patients treated with chemotherapy

OBJECTIVE

To determine whether the use of protease inhibitor (PI)-based antiretroviral (ARV) therapy had an impact on the survival of patients with human immunodeficiency virus (HIV) infection-associated Kaposi's sarcoma (KS) who were receiving systemic chemotherapy.

METHOD

Records of 48 AIDS patients with extensive KS who received chemotherapy from 1995 to 1999 were reviewed. Analysis by presence or absence of PI treatment was undertaken, and patients who were receiving nonnucleoside reverse transcriptase inhibitors (NNRTIs) were excluded from the analysis.

RESULTS

Median age was 38 years, and 47 patients were men having sex with men. Half of the patients (54%) had at least one prior AIDS-defining event. Median CD4 count at diagnosis of KS was 28 cells/microL (range, 1-625). Visceral KS was present in 33 patients (69%), and the remainder of patients had extensive and symptomatic cutaneous and/or mucous membrane involvement. All patients received at least one cycle of chemotherapy, including vincristine/bleomycin or an anthracycline-containing regimen. There was a significant difference in the median survival (MS) between the 28 patients (58%) treated with PI-based antiretroviral therapy (31 months [range, 1.8-48]) and the group not receiving PI (7 months [range, 1-28], p =.0001). In addition, 81% of patients in the PI group were alive at 18 months from initiation of chemotherapy versus 12% in the non-PI group. Twenty patients (71%) in the PI-treated group were able to discontinue chemotherapy for at least 1 month after remission of KS, in comparison to 3 of 20 (15%) patients in the group of patients who did not receive PI (p =.00001). Death due to KS occurred in 6 of 28 (21%) patients (total 9 deaths) in the PI group and 14 of 20 (70%) patients (total 18 deaths) in the non-PI group (p =.001).

CONCLUSION

In a nonselected group of patients with advanced and extensive KS in a real-life clinical setting, our results show a survival benefit and a decrease in KS-related death for patients receiving chemotherapy and PI-based ARV therapy when compared to patients not receiving PI-based therapy. Discontinuation of chemotherapy in patients receiving PI-based antiretroviral therapy appears to be feasible in patients who attain remission of KS.