Enhanced atmospheric oxidation toward carbon neutrality reduces methane's climate forcing

The hydroxyl radical (OH), as the central atmospheric oxidant, controls the removal rates of methane, a powerful greenhouse gas. It is being suggested that OH levels would decrease with reductions of nitrogen oxides and ozone levels by climate polices, but this remains unsettled. Here, we show that driven by the carbon neutrality pledge, the global-mean OH concentration, derived from multiple chemistry-climate model simulations, is projected to be significantly increasing with a trend of 0.071‒0.16% per year during 2015-2100. The leading cause of this OH enhancement is dramatic decreases in carbon monoxide and methane concentrations, which together reduce OH sinks. The OH increase shortens methane's lifetime by 0.19‒1.1 years across models and subsequently diminishes methane's radiative forcing. If following a largely unmitigated scenario, the global OH exhibits a significant decrease that would exacerbate methane's radiative forcing. Thus, we highlight that targeted emission abatement strategies for sustained oxidation capacity can benefit climate change mitigation in the Anthropocene.

Threefold reduction of modeled uncertainty in direct radiative effects over biomass burning regions by constraining absorbing aerosols

Absorbing aerosols emitted from biomass burning (BB) greatly affect the radiation balance, cloudiness, and circulation over tropical regions. Assessments of these impacts rely heavily on the modeled aerosol absorption from poorly constrained global models and thus exhibit large uncertainties. By combining the AeroCom model ensemble with satellite and in situ observations, we provide constraints on the aerosol absorption optical depth (AAOD) over the Amazon and Africa. Our approach enables identification of error contributions from emission, lifetime, and MAC (mass absorption coefficient) per model, with MAC and emission dominating the AAOD errors over Amazon and Africa, respectively. In addition to primary emissions, our analysis suggests substantial formation of secondary organic aerosols over the Amazon but not over Africa. Furthermore, we find that differences in direct aerosol radiative effects between models decrease by threefold over the BB source and outflow regions after correcting the identified errors. This highlights the potential to greatly reduce the uncertainty in the most uncertain radiative forcing agent.

Financial incentives for infection prevention and antimicrobial stewardship to reduce antibiotic use: Japan's nationwide observational study

BACKGROUND

The Japanese government introduced financial incentives to reduce nationwide antibiotic use in hospital settings.

AIM

This study aimed to determine whether the nationwide financial incentives for creating infection prevention and control (IPC) teams introduced in 2012 and antimicrobial stewardship (ASP) teams introduced in 2018 were associated with changes in antibiotic use and health resource utilization at a national level.

METHODS

We conducted time-series analyses and a difference-in-differences study consisting of 3,057,517 inpatients with infectious diseases from 472 medical facilities during fiscal years 2011-2018 using a nationally representative inpatient database in Japan. The primary outcome was the days of therapy (DOT) of antibiotic use per 100 patient-days (PDs). The secondary outcomes consisted of types of antibiotic used, health resource utilization, and mortality.

RESULTS

A total of 5,201,304 financial incentives were observed during 2012-2018, which resulted in a total of 12.1 billion JPY (≈110 million USD). Time-series analyses found decreasing trends in total antibiotic use (79.3-72.5 DOTs/100 PDs (8.6% reduction)) and carbapenem use (9.0-7.0 DOTs/100 PDs (7.8% reduction)) from 2011 to 2018 without adversely affecting other healthcare outcomes (e.g., mortality). In the difference-in-differences analyses, we did not observe meaningful changes in total antibiotic use between the incentivized and unincentivized hospitals for ASP teams, except for the northern part of Japan. No dose-response relationships were observed between the amount of financial incentives and reductions in antibiotic use during 2011-2019.

CONCLUSIONS

Further research and efforts are needed to accelerate antimicrobial stewardship in hospital settings in Japan.

A pregnant woman with thymoma-associated pure red cell aplasia

Background

Pure red cell aplasia (PRCA) is a hematological disorder characterized by anemia with severe reticulocytopenia caused by a marked reduction in erythroid precursors in the bone marrow. PRCA is known to be associated with pregnancy, but thymoma-associated PRCA during pregnancy is very rare, and its successful management has not been reported.

Case presentation

A 37-year-old primiparous woman with severe anemia was referred to our center at 27 weeks’ gestation. She was diagnosed with PRCA based on bone aspiration findings at 33 weeks’ gestation. Magnetic resonance imaging (MRI) revealed an anterior mediastinal mass 4 cm in size suspected of being thymoma. She was therefore diagnosed with thymoma-associated PRCA during pregnancy. Surgery for thymoma was planned after delivery, since the imaging findings were suggestive of early-stage thymoma (Masaoka stage I or II). With transfusion of a total 3,360 ml of red blood cells (RBCs) during pregnancy, the patient gave birth to a baby girl weighing 2,548 g at 40 weeks’ gestation. The baby showed transient congenital cutaneous candidiasis. The placental pathology revealed subamniotic inflammation with a fungal structure. Treatment with topical anti-fungal cream immediately ameliorated the baby’s skin lesion. Maternal anemia did not improve after delivery; however, the thymoma did not increase in size. At five months after delivery, the mother underwent thymectomy with oral cyclosporine A. A pathological examination revealed Masaoka stage II-a thymoma. She completely had recovered from anemia at six months after surgery. Cyclosporine A treatment was discontinued three years after surgery. Remission has been sustained for four years since surgery.

Conclusions

A very rare case of thymoma-associated PRCA during pregnancy was diagnosed without any subjective symptoms and was expectantly managed, resulting in a good prognosis. Although bone marrow aspiration during pregnancy is an invasive test, it is important to confirm the diagnosis. Conservative management with blood transfusion was possible for early-stage thymoma-associated PRCA during pregnancy. Active surveys, including MRI, for PRCA during pregnancy led to the detection of thymoma at an early stage and the achievement of a preferable pregnancy outcome.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-05145-5.

Risk factors and outcomes of abnormal bleeding after external cephalic version

OBJECTIVES

To present the consequences of and risk factors for abnormal bleeding after ECV (external cephalic version).

METHODS

We conducted a retrospective chart review at a single center in Japan. Abnormal bleeding was defined as vaginal bleeding and/or intrauterine hemorrhage. We descriptively assessed birth outcomes among women with abnormal bleeding, and investigated the risk factors using a logistic regression analysis.

RESULTS

Of 477 women who received ECV, 39 (8.2%) showed abnormal bleeding, including 16 (3.4%) with intrauterine hemorrhage. Of the 16 women with intrauterine hemorrhage, 14 required emergency cesarean section; none experienced placental abruption, a low Apgar score at 5 min (<7), or low umbilical cord artery pH (<7.1). Among 23 women who had vaginal bleeding without intrauterine hemorrhage, four cases underwent emergency cesarean section and one case of vaginal delivery involved placental abruption. The risk of abnormal bleeding was higher in women with a maximum vertical pocket (MVP) of <40 mm in comparison to those with an MVP of >50 mm (adjusted odds ratio [OR]: 3.48, 95% confidence interval [CI]: 1.23-9.90), as was higher in women with unsuccessful ECV than in those with successful ECV (aOR: 4.54, 95% CI: 1.95-10.6).

CONCLUSIONS

A certain number of women who underwent ECV had abnormal bleeding, including vaginal bleeding and/or intrauterine hemorrhage, many of them resulted in emergency cesarean section. Although all of cases with abnormal bleeding had good birth outcomes, one case of vaginal bleeding was accompanied by placental abruption. Small amniotic fluid volume and unsuccessful ECV are risk factors for abnormal bleeding.

Comparison of postoperative infection after emergency inguinal hernia surgery with enterectomy between mesh repair and non-mesh repair: a national database analysis

PURPOSE

Synthetic non-absorbable mesh is used for elective inguinal hernia repair but is not commonly used for incarcerated or strangulated inguinal hernia requiring enterectomy to reduce the risk of surgical-site infection. This study aimed to evaluate the safety of synthetic non-absorbable mesh repair in patients with incarcerated or strangulated inguinal hernia requiring enterectomy versus non-mesh repair.

METHODS

We analyzed patients with incarcerated or strangulated inguinal hernia with enterectomy from April 2012 to March 2017 using a nationwide inpatient database in Japan. We conducted overlap propensity score-weighted analyses to compare surgical-site infection (SSI), duration of anesthesia, antibiotic use at > 3 days after surgery, postoperative hospital stay, and 30 day readmission. Two sensitivity analyses were performed. First, we compared the proportions of patients requiring wound culture at ≥ 3 days after surgery. Second, we performed overlap propensity score-weighted logistic regression analyses for surgical-site infection.

RESULTS

We identified 668 eligible patients, comprising 223 patients with mesh repair and 445 with non-mesh repair. Overlap propensity score-weighted analyses showed no significant differences between the mesh repair and non-mesh repair groups for SSI (2.5 vs. 2.8%, P = 0.79). Secondary outcomes did not differ significantly between the groups. Proportion of wound culture at ≥ 3 days after surgery was similar in the two groups (11.1 vs. 14.6%, P = 0.18). Logistic regression analysis showed no significant association between mesh repair and SSI (odds ratio, 0.93; 95% confidence interval, 0.34-2.57).

CONCLUSION

Synthetic non-absorbable mesh use may be safe for incarcerated or strangulated inguinal hernia requiring enterectomy.

Breast cancer surgery in patients with schizophrenia: short-term outcomes from a nationwide cohort

BACKGROUND

Although patients with schizophrenia have a higher risk of developing breast cancer than the general population, studies that have investigated postoperative complications after breast cancer surgery in patients with schizophrenia are scarce. This study examined associations between schizophrenia and short-term outcomes following breast cancer surgery.

METHODS

Patients who underwent surgery for stage 0-III breast cancer between July 2010 and March 2017 were identified from a Japanese nationwide inpatient database. Multivariable analyses were conducted to compare postoperative complications and hospitalization costs between patients with schizophrenia and those without any psychiatric disorder. Three sensitivity analyses were performed: a 1 : 4 matched-pair cohort analysis with matching for age, institution, and fiscal year at admission; analyses excluding patients with schizophrenia who were not taking antipsychotic medication; and analyses excluding patients with schizophrenia who were admitted to hospital involuntarily.

RESULTS

The study included 3660 patients with schizophrenia and 350 860 without any psychiatric disorder. Patients with schizophrenia had a higher in-hospital morbidity (odds ratio (OR) 1.37, 95 per cent c.i. 1.21 to 1.55), with more postoperative bleeding (OR 1.34, 1.05 to 1.71) surgical-site infections (OR 1.22, 1.04 to 1.43), and sepsis (OR 1.20, 1.03 to 1.41). The total cost of hospitalization (coefficient €743, 95 per cent c.i. 680 to 806) was higher than that for patients without any psychiatric disorder. All sensitivity analyses showed similar results to the main analyses.

CONCLUSION

Although causal inferences remain premature, multivariable regression analyses showed that schizophrenia was associated with greater in-hospital morbidity and higher total cost of hospitalization after breast cancer surgery than in the general population.

Age in months and birth order in infant nonfatal injuries: A retrospective cohort study

Objective

To examine the age in months at which infants visited outpatient clinics or emergency rooms for the first time for nonfatal injuries and to identify risk factors for the occurrence of these injuries.

Study design

Retrospective cohort study.

Methods

We used a health insurance claims database in Japan. Infants born between April 2012 and December 2014 were identified and followed until 12 months of age. We identified their first visit to outpatient clinics or emergency rooms because of nonfatal injuries (wounds/fractures, foreign bodies, and burns). Cox regression analysis was used to examine the association of nonfatal injuries with infants’ sex, birth order, and parental age.

Results

We identified 46,431 eligible infants. Of these, 7606 (16.4%) were brought to an outpatient clinic or emergency room for nonfatal injuries within 12 months of birth. Of the 7,606, 21.7% were aged ≤4 months and 44.7% ​≤ ​7 months. First-born infants were more likely to have wounds/fractures and burns.

Conclusion

One-fifth of first nonfatal infant injuries occurred within 4 months of age. Healthcare providers should provide early education about injury prevention, especially to caregivers of first-born infants.

•

Nonfatal injuries within first year of birth occurred in 16% of infants.

•

22% of first injuries occurred within 4 months of birth.

•

First-born infants were more likely to have wounds/fractures and burns.

Rechallenge of voriconazole successfully tolerated after hepatic toxicity

Infections caused by Aspergillus species are often life-threatening. Drugs effective for Aspergillus infection are limited. Voriconazole is one of the most important drugs, however, considerable portion of patients experience liver toxicity and have to stop the drug administration. We frequently experience liver toxicity even though the serum concentration of voriconazole is within the target range. Historically, in some life-threatening situations like tuberculosis, where a suitable alternative is unavailable, rechallenge has been attempted. However, there have been no report on the rechallenge of voriconazole. We report cases of successful re-administration of voriconazole after liver toxicity.

Stent as a bridge to surgery or immediate colectomy for malignant right colonic obstruction: propensity-scored, national database study

Background

The aim of this study was to compare perioperative outcomes of urgent colectomy and placement of a self-expanding metallic stent followed by colectomy for patients with malignant right colonic obstruction. Right-sided malignant obstruction is less common than left-sided. Stenting for malignant left colonic obstruction has been reported to reduce postoperative complications. However, the impact of stenting for malignant right colonic obstruction remains undefined.

Methods

The study included patients with right-sided malignant obstruction or stenosis undergoing colectomy between April 2012 and March 2017 identified from a nationwide database. Propensity score matching analysis was used to compare mortality and morbidity rates, proportion receiving a stoma and postoperative stay between urgent colectomy and stent groups.

Results

From 9572 patients, 1500 pairs were generated by propensity score matching. There was no significant difference in in-hospital mortality between the urgent colostomy and stent groups (1·6 versus 0·9 per cent respectively; P = 0·069). Complications were more common after urgent colectomy than stenting (22·1 versus 19·1 per cent; P = 0·042). Surgical-site infection was more likely with urgent colectomy (7·1 versus 4·4 per cent; P = 0·001). There was no significant difference between the two groups in anastomotic leakage (3·8 versus 2·6 per cent; P = 0·062). The proportion of patients needing a stoma was higher with urgent colectomy than primary treatment with stents (5·1 versus 1·7 per cent; P &lt; 0·001). Postoperative stay was longer after urgent colectomy (15 versus 13 days; P &lt; 0·001).

Conclusion

Stenting followed by colectomy in patients with malignant right colonic obstruction may provide more favourable perioperative outcomes than urgent colectomy.

Evaluation of an amplicon-based custom gene panel for the diagnosis of hereditary tumors

Genetic testing based on next-generation sequencing (NGS) analysis has recently been used to diagnose hereditary diseases. In this study, we explored the usefulness of our custom amplicon panel that targeted 23 genes related to hereditary tumors given in the American College of Medical Genetics and Genomics recommendations. We applied our custom NGS panel to samples from 12 patients previously diagnosed by Sanger sequencing as having the diseases or diagnosed clinically by meeting the diagnostic criteria in this study. Our gene panel not only successfully identified all variants detected by Sanger sequencing but also identified previously unrecognized variants that resulted in confirmation of the disease, or even in the revision of the diagnosis. For instance, a patient identified with an SDHD gene mutation actually had von Hippel-Lindau (VHL) syndrome, as determined by the presence of a pathogenic VHL gene variant. We also identified false-positive results that were generated by amplification of genome regions that are not intended to be investigated. In conclusion, NGS-based amplicon sequencing is a highly effective method to detect germline variants, as long as they are also carefully reviewed by manual inspection.

Liver resection with thrombectomy for patients with hepatocellular carcinoma and tumour thrombus in the inferior vena cava or right atrium

Background

Hepatocellular carcinoma (HCC) with tumour thrombus (TT) in the inferior vena cava (IVC) or right atrium (RA) is a rare advanced disease state with a poor prognosis. The aim of this study was to examine survival after surgical resection.

Methods

Patients with HCC and TT of either the IVC or RA, who underwent liver resection between February 1997 and July 2017, were included. Their short‐ and long‐term outcomes and surgical details were analysed retrospectively.

Results

Thirty‐seven patients were included; 16 patients had TT in the IVC below the diaphragm, eight had TT in the IVC above the diaphragm, and 13 had TT entering the RA. Twelve patients had advanced portal vein TT (portal vein invasion (Vp) greater than Vp3 and Vp4), ten had bilobar disease, and 12 had extrahepatic disease. There were no in‐hospital deaths, although two patients died within 90 days. Median survival did not differ between patients who had resection with curative intent (18·7 months) and those with residual tumour in the lung only (20·7 months), but survival was poor for patients with residual tumour in the liver (8·3 months).

Conclusion

Liver resection with thrombectomy for advanced HCC with TT in the IVC or RA is safe and feasible, leading to moderate survival.

Secretory IgA accumulated in the airspaces of idiopathic pulmonary fibrosis and promoted VEGF, TGF-β and IL-8 production by A549 cells

Secretory IgA (SIgA) is a well-known mucosal-surface molecule in first-line defense against extrinsic pathogens and antigens. Its immunomodulatory and pathological roles have also been emphasized, but it is unclear whether it plays a pathological role in lung diseases. In the present study, we aimed to determine the distribution of IgA in idiopathic pulmonary fibrosis (IPF) lungs and whether IgA affects the functions of airway epithelial cells. We performed immunohistochemical analysis of lung sections from patients with IPF and found that mucus accumulated in the airspaces adjacent to the hyperplastic epithelia contained abundant SIgA. This was not true in the lungs of non-IPF subjects. An in-vitro assay revealed that SIgA bound to the surface of A549 cells and significantly promoted production of vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β and interleukin (IL)-8, important cytokines in the pathogenesis of IPF. Among the known receptors for IgA, A549 cells expressed high levels of transferrin receptor (TfR)/CD71. Transfection experiments with siRNA targeted against TfR/CD71 followed by stimulation with SIgA suggested that TfR/CD71 may be at least partially involved in the SIgA-induced cytokine production by A549 cells. These phenomena were specific for SIgA, distinct from IgG. SIgA may modulate the progression of IPF by enhancing synthesis of VEGF, TGF-β and IL-8.

Evaluation of global simulations of aerosol particle and cloud condensation nuclei number, with implications for cloud droplet formation

A total of 16 global chemistry transport models and general circulation models have participated in this study; 14 models have been evaluated with regard to their ability to reproduce the near-surface observed number concentration of aerosol particles and cloud condensation nuclei (CCN), as well as derived cloud droplet number concentration (CDNC). Model results for the period 2011-2015 are compared with aerosol measurements (aerosol particle number, CCN and aerosol particle composition in the submicron fraction) from nine surface stations located in Europe and Japan. The evaluation focuses on the ability of models to simulate the average across time state in diverse environments and on the seasonal and short-term variability in the aerosol properties. There is no single model that systematically performs best across all environments represented by the observations. Models tend to underestimate the observed aerosol particle and CCN number concentrations, with average normalized mean bias (NMB) of all models and for all stations, where data are available, of -24% and -35% for particles with dry diameters > 50 and > 120nm, as well as -36% and -34% for CCN at supersaturations of 0.2% and 1.0%, respectively. However, they seem to behave differently for particles activating at very low supersaturations (< 0.1 %) than at higher ones. A total of 15 models have been used to produce ensemble annual median distributions of relevant parameters. The model diversity (defined as the ratio of standard deviation to mean) is up to about 3 for simulated N3 (number concentration of particles with dry diameters larger than 3 nm) and up to about 1 for simulated CCN in the extra-polar regions. A global mean reduction of a factor of about 2 is found in the model diversity for CCN at a supersaturation of 0.2% (CCN0.2) compared to that for N3, maximizing over regions where new particle formation is important. An additional model has been used to investigate potential causes of model diversity in CCN and bias compared to the observations by performing a perturbed parameter ensemble (PPE) accounting for uncertainties in 26 aerosol-related model input parameters. This PPE suggests that biogenic secondary organic aerosol formation and the hygroscopic properties of the organic material are likely to be the major sources of CCN uncertainty in summer, with dry deposition and cloud processing being dominant in winter. Models capture the relative amplitude of the seasonal variability of the aerosol particle number concentration for all studied particle sizes with available observations (dry diameters larger than 50, 80 and 120 nm). The short-term persistence time (on the order of a few days) of CCN concentrations, which is a measure of aerosol dynamic behavior in the models, is underestimated on average by the models by 40% during winter and 20% in summer. In contrast to the large spread in simulated aerosol particle and CCN number concentrations, the CDNC derived from simulated CCN spectra is less diverse and in better agreement with CDNC estimates consistently derived from the observations (average NMB -13% and -22% for updraft velocities 0.3 and 0.6 ms-1, respectively). In addition, simulated CDNC is in slightly better agreement with observationally derived values at lower than at higher updraft velocities (index of agreement 0.64 vs. 0.65). The reduced spread of CDNC compared to that of CCN is attributed to the sublinear response of CDNC to aerosol particle number variations and the negative correlation between the sensitivities of CDNC to aerosol particle number concentration (∂N d/∂N a) and to updraft velocity (∂N d/∂w). Overall, we find that while CCN is controlled by both aerosol particle number and composition, CDNC is sensitive to CCN at low and moderate CCN concentrations and to the updraft velocity when CCN levels are high. Discrepancies are found in sensitivities ∂N d/∂N a and ∂N d/∂w; models may be predisposed to be too "aerosol sensitive" or "aerosol insensitive" in aerosol-cloud-climate interaction studies, even if they may capture average droplet numbers well. This is a subtle but profound finding that only the sensitivities can clearly reveal and may explain inter-model biases on the aerosol indirect effect.

Nationwide observational study of mortality from complicated intra-abdominal infections and the role of bacterial cultures

BACKGROUND

The benefit of taking intra-abdominal cultures during source control procedures in patients with complicated intra-abdominal infection (CIAI) is unknown. The aim of this study was to evaluate whether intra-abdominal cultures reduce the mortality rate of CIAI.

METHODS

The Japanese Diagnosis Procedure Combination database was used to identify adult patients with CIAI who had undergone source control procedures on the first day of admission to hospital between April 2014 and March 2016. In-hospital mortality was compared between patients who did and those who did not have intra-abdominal cultures taken. A generalized linear mixed-effect logistic regression model and a random intercept per hospital were used to adjust for baseline confounders and institutional differences. Subgroup analyses were also performed according to disease cause, site of onset and severity of CIAI.

RESULTS

Intra-abdominal cultures were taken from 16 303 of 41 495 included patients. Multivariable logistic regression analysis showed that patients with intra-abdominal cultures had a significantly lower mortality than those without (odds ratio 0·85, 95 per cent c.i. 0·77 to 0·95). Subgroup analyses revealed statistically significant differences in mortality between patients with and without cultures among those with lower intestinal perforation, biliary tract infection/perforation, healthcare-associated CIAI and high-risk community-acquired CIAI.

CONCLUSIONS

Intra-abdominal cultures obtained during source control procedures may reduce in-hospital mortality, especially in patients with lower intestinal perforation, biliary tract infection/perforation, or healthcare-associated or high-risk community-acquired CIAI.

Secretory immunoglobulin A induces human lung fibroblasts to produce inflammatory cytokines and undergo activation

Immunoglobulin (Ig)A is the most abundant immunoglobulin in humans, and in the airway mucosa secretory IgA (sIgA) plays a pivotal role in first-line defense against invading pathogens and antigens. IgA has been reported to also have pathogenic effects, including possible worsening of the prognosis of idiopathic pulmonary fibrosis (IPF). However, the precise effects of IgA on lung fibroblasts remain unclear, and we aimed to elucidate how IgA activates human lung fibroblasts. We found that sIgA, but not monomeric IgA (mIgA), induced interleukin (IL)-6, IL-8, monocyte chemoattractant protein (MCP)-1 and granulocyte-macrophage colony-stimulating factor (GM-CSF) production by normal human lung fibroblasts (NHLFs) at both the protein and mRNA levels. sIgA also promoted proliferation of NHLFs and collagen gel contraction comparable to with transforming growth factor (TGF)-β, which is involved in fibrogenesis in IPF. Also, Western blot analysis and real-time quantitative polymerase chain reaction (PCR) revealed that sIgA enhanced production of α-smooth muscle actin (α-SMA) and collagen type I (Col I) by NHLFs. Flow cytometry showed that NHLFs bound sIgA, and among the known IgA receptors, NHLFs significantly expressed CD71 (transferrin receptor). Transfection of siRNA targeting CD71 partially but significantly suppressed cytokine production by NHLFs co-cultured with sIgA. Our findings suggest that sIgA may promote human lung inflammation and fibrosis by enhancing production of inflammatory or fibrogenic cytokines as well as extracellular matrix, inducing fibroblast differentiation into myofibroblasts and promoting human lung fibroblast proliferation. sIgA's enhancement of cytokine production may be due partially to its binding to CD71 or the secretory component.

Black carbon radiative effects highly sensitive to emitted particle size when resolving mixing-state diversity

Post-industrial increases in atmospheric black carbon (BC) have a large but uncertain warming contribution to Earth's climate. Particle size and mixing state determine the solar absorption efficiency of BC and also strongly influence how effectively BC is removed, but they have large uncertainties. Here we use a multiple-mixing-state global aerosol microphysics model and show that the sensitivity (range) of present-day BC direct radiative effect, due to current uncertainties in emission size distributions, is amplified 5-7 times (0.18-0.42 W m-2) when the diversity in BC mixing state is sufficiently resolved. This amplification is caused by the lifetime, core absorption, and absorption enhancement effects of BC, whose variability is underestimated by 45-70% in a single-mixing-state model representation. We demonstrate that reducing uncertainties in emission size distributions and how they change in the future, while also resolving modeled BC mixing state diversity, is now essential when evaluating BC radiative effects and the effectiveness of BC mitigation on future temperature changes.

Preoperative oral care and effect on postoperative complications after major cancer surgery

Background

Improving patients' oral hygiene is an option for preventing postoperative pneumonia that may be caused by aspiration of oral and pharyngeal secretions. Whether preoperative oral care by a dentist can decrease postoperative complications remains controversial. A retrospective cohort study was undertaken to assess the association between preoperative oral care and postoperative complications among patients who underwent major cancer surgery.

Methods

The nationwide administrative claims database in Japan was analysed. Patients were identified who underwent resection of head and neck, oesophageal, gastric, colorectal, lung or liver cancer between May 2012 and December 2015. The primary outcomes were postoperative pneumonia and all-cause mortality within 30 days of surgery. Patient background was adjusted for with inverse probability of treatment weighting using propensity scoring.

Results

Of 509 179 patients studied, 81 632 (16·0 per cent) received preoperative oral care from a dentist. A total of 15 724 patients (3·09 per cent) had postoperative pneumonia and 1734 (0·34 per cent) died within 30 days of surgery. After adjustment for potential confounding factors, preoperative oral care by a dentist was significantly associated with a decrease in postoperative pneumonia (3·28 versus 3·76 per cent; risk difference − 0·48 (95 per cent c.i. −0·64 to−0·32) per cent) and all-cause mortality within 30 days of surgery (0·30 versus 0·42 per cent; risk difference − 0·12 (−0·17 to −0·07) per cent).

Conclusion

Preoperative oral care by a dentist significantly reduced postoperative complications in patients who underwent cancer surgery.

Anthropogenic combustion iron as a complex climate forcer

Atmospheric iron affects the global carbon cycle by modulating ocean biogeochemistry through the deposition of soluble iron to the ocean. Iron emitted by anthropogenic (fossil fuel) combustion is a source of soluble iron that is currently considered less important than other soluble iron sources, such as mineral dust and biomass burning. Here we show that the atmospheric burden of anthropogenic combustion iron is 8 times greater than previous estimates by incorporating recent measurements of anthropogenic magnetite into a global aerosol model. This new estimation increases the total deposition flux of soluble iron to southern oceans (30-90 °S) by 52%, with a larger contribution of anthropogenic combustion iron than dust and biomass burning sources. The direct radiative forcing of anthropogenic magnetite is estimated to be 0.021 W m^-2 globally and 0.22 W m^-2 over East Asia. Our results demonstrate that anthropogenic combustion iron is a larger and more complex climate forcer than previously thought, and therefore plays a key role in the Earth system.

Anthropogenic combustion iron as a complex climate forcer

Atmospheric iron affects the global carbon cycle by modulating ocean biogeochemistry through the deposition of soluble iron to the ocean. Iron emitted by anthropogenic (fossil fuel) combustion is a source of soluble iron that is currently considered less important than other soluble iron sources, such as mineral dust and biomass burning. Here we show that the atmospheric burden of anthropogenic combustion iron is 8 times greater than previous estimates by incorporating recent measurements of anthropogenic magnetite into a global aerosol model. This new estimation increases the total deposition flux of soluble iron to southern oceans (30–90 °S) by 52%, with a larger contribution of anthropogenic combustion iron than dust and biomass burning sources. The direct radiative forcing of anthropogenic magnetite is estimated to be 0.021 W m⁻² globally and 0.22 W m⁻² over East Asia. Our results demonstrate that anthropogenic combustion iron is a larger and more complex climate forcer than previously thought, and therefore plays a key role in the Earth system.

As a source of soluble iron, anthropogenic combustion iron is considered less important than natural sources. Here, the authors combine new measurements with a global aerosol model and show the atmospheric burden of anthropogenic combustion iron to be 8 times greater than previous estimates.

Abstract P1-05-05: Hyperthermia regulates transporter expression via ROS production and enhances the cytotoxicity of doxorubicin

Introduction: Hyperthermia (HT) is a non-invasive cancer therapy. Treatment temperature between 41°C to 44°C has no cytotoxic damage in normal cells, however shows cytotoxicity in cancer cells because of the underdeveloped vascular system. HT often used with other cancer therapy such as radiation therapy and chemotherapy. However mechanism of synergistic effect using these therapies remains unclear. Compared to 37°C, 42°C is mild heat stress for cells, thus superoxide anion is released from tissue. Superoxide anion is produced by mitochondrial electron transport chain. Reactive oxygen species (ROS), produced by mild heat stress, can be released from mitochondria. We have previously reported that ATP-binding cassette sub-family G member 2 (ABCG2) expression was suppressed by increasing mitochondrial ROS, and induction of the cancer specific porphyrin accumulation. ABCG2 is a transporter of doxorubicin (DOX), therefore we hypothesized that synergistic effect of HT and chemotherapy would be induced by down-regulation of ABCG2 expression via intracellular ROS increase. In this study, we investigated if cytotoxic effect of breast cancer cell using DOX can be enhance by HT via intracellular ROS increase.

Materials and methods: The murine breast cancer cell line, 4T1E was incubated at 37°C or 42°C for 1h. Intracellular ROS generation after HT treatment was detected by electron spin resonance (ESR). Twenty four hours after HT treatment, cells were incubated in medium containing 0, 0.1 and 1 μM DOX for 24 h. Cell viability was measured using the Cell Counting Kit 8, a water-soluble tetrazolium-8 based colorimetric assay. ABCG2 expression in whole cells was analyzed by Western blotting.

Results and discussion: ESR signal peak with HT treatment became high as compared to without HT treatment, indicating intracellular ROS level was increased by HT treatment. Cell viability and ABCG2 expression were decreased by DOX exposure and by HT treatment. The enhancement of HT treatment effect by DOX is considered to be result of down-regulation of ABCG2 expression by ROS. When cells were exposed to DOX with 5-aminolevulinic acid (ALA), cell viability reduced further. Since it is known that porphyrin is introduced by ALA and is transported by ABCG2, we speculate that ALA worked as a competitive inhibitor of DOX excretion transporter to enhance cell death. ESR signal peak in ALA treatment cells was higher than that in non-ALA treatment cells. Significant increase in cellular damage by HT treatment was shown by adding ALA, but not without ALA. Moreover, cell death induced by HT and ALA treatment was suppressed by adding N-acetylcysteine (NAC), which is an antioxidant. These results suggest that cellular damage of HT treatment is due to ROS production induced by ALA.

Conclusion: HT treatment involved intracellular ROS production and down-regulated the expression of ABCG2 protein. HT treatment also enhanced the cell damage by DOX. Cell death by DOX was enhanced by combination with HT and ALA treatment, possibly via intracellular ROS generation, and was suppressed by additing antioxidant.

Citation Format: Terasaki A, Kurokawa H, Terasaki M, Ito H, Matsui H, Ichioka E, Tsushima Y, Manaka-Iguchi A, Bando H, Hara H. Hyperthermia regulates transporter expression via ROS production and enhances the cytotoxicity of doxorubicin [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-05-05.

Association between hospital volume and in-hospital mortality following radiofrequency ablation for hepatocellular carcinoma

Background

Radiofrequency ablation (RFA) is a minimally invasive treatment for hepatocellular carcinoma (HCC). There is increasing evidence of an association between increasing hospital volume and lower postoperative mortality for many surgical procedures, but this is difficult to establish with minimally invasive treatments, where postoperative mortality is low. The aim of this study was to investigate the relationship between hospital volume and in-hospital mortality following RFA using a Japanese nationwide database.

Methods

Data from the Diagnostic Procedure Combination database were analysed from 1 July 2010 to 31 March 2012. Multivariable logistic regression was used to analyse the relationship between hospital volume and in-hospital mortality following RFA, with adjustment for patient background.

Results

Some 36 675 patients with HCC were identified in the database. The overall in-hospital mortality rate from RFA was 0·31 per cent. In-hospital mortality was significantly higher in low-volume than high-volume hospitals (odds ratio 2·57, 95 per cent c.i. 1·61 to 4·09; P < 0·001). Higher in-hospital mortality was significantly associated with older age and a higher Charlson Co-morbidity Index score.

Conclusion

RFA for HCC was associated with acceptably low mortality in Japan, but in-hospital mortality following RFA was affected by hospital procedural volume.

Epidural analgesia is infrequently used in patients with acute pancreatitis : a retrospective cohort study

BACKGROUNDS AND AIMS

Epidural analgesia is an option for pain control in patients with acute pancreatitis. The aim of this study is to describe characteristics, morbidity and mortality of patients with acute pancreatitis treated with epidural analgesia.

PATIENTS AND METHODS

Data was extracted from a national inpatient database in Japan on patients hospitalized with acute pancreatitis between July 2010 and March 2013. A total of 44,146 patients discharged from acute care hospitals were included in this retrospective cohort study. The patient background, timing and duration of epidural analgesia, complications (epidural hematoma or abscess), surgery (for cholelithiasis / cholecystitis or complications) and mortality were verified.

RESULTS

Epidural analgesia was used in 307 patients (0.70 %). The mean age was 64.0 years (standard deviation, 15.4 years) and 116 (37.8%) of the patients were female. The median duration of epidural analgesia was four days (interquartile range, 3-5 days). No patient underwent surgery for epidural hematoma or abscess. Six (2.0%) patients died during hospitalization. Most likely causes of death were pulmonary embolism, multiple organ failure, sepsis, and methicillin-resistant staphylococcus aureus enterocolitis. The responsible physician for 250 of the patients (81.4%) was a gastroenterological surgeon. Epidural analgesia was started on the day of surgery in 278 (90.6%) patients.

CONCLUSION

Epidural analgesia is rarely used in patients with acute pancreatitis. None of the patients included in the study required surgery for epidural hematoma or abscess. Further research to evaluate the efficacy and safety of epidural analgesia in patients with acute pancreatitis is warranted.

Effectiveness of early administration of tranexamic acid in patients with severe trauma

BACKGROUND

A reduction in mortality with the early use of tranexamic acid has been demonstrated in severely injured patients who are bleeding. However, the modest treatment effect with no reduction in blood transfusion has raised concerns. The aim of the present study was to estimate the effectiveness of regular use of tranexamic acid in severely injured patients.

METHODS

This multicentre observational study used retrospectively collected data from consecutive injured patients (Injury Severity Score at least 16) treated in 15 Japanese academic institutions in 2012. A propensity score-matched analysis compared patients who did or did not receive tranexamic acid administration within 3 h of injury. Study outcomes included 28-day all-cause and cause-specific mortality, and need for blood transfusion.

RESULTS

Of 796 eligible subjects, 281 were treated with tranexamic acid. Propensity score matching selected a total of 500 matched subjects (250 in each group). Tranexamic acid administration was associated with lower 28-day mortality (10·0 versus 18·4 per cent; difference -8·4 (95 per cent c.i. -14·5 to -2·3) per cent) and lower 28-day mortality from primary brain injury (6·0 versus 13·2 per cent; difference -7·2 (-12·3 to -2·1) per cent). However, there was no significant difference between groups in the need for blood transfusion (33·2 versus 34·8 per cent; difference -1·6 (-9·9 to 6·7) per cent).

CONCLUSION

Early tranexamic acid use was associated with reduced mortality in severely injured patients, in particular those with a primary brain injury.

A novel LSD1 inhibitor NCD38 ameliorates MDS-related leukemia with complex karyotype by attenuating leukemia programs via activating super-enhancers

Lysine-specific demethylase 1 (LSD1) regulates gene expression by affecting histone modifications and is a promising target for acute myeloid leukemia (AML) with specific genetic abnormalities. Novel LSD1 inhibitors, NCD25 and NCD38, inhibited growth of MLL-AF9 leukemia as well as erythroleukemia, megakaryoblastic leukemia and myelodysplastic syndromes (MDSs) overt leukemia cells in the concentration range that normal hematopoiesis was spared. NCD25 and NCD38 invoked the myeloid development programs, hindered the MDS and AML oncogenic programs, and commonly upregulated 62 genes in several leukemia cells. NCD38 elevated H3K27ac level on enhancers of these LSD1 signature genes and newly activated ~500 super-enhancers. Upregulated genes with super-enhancer activation in erythroleukemia cells were enriched in leukocyte differentiation. Eleven genes including GFI1 and ERG, but not CEBPA, were identified as the LSD1 signature with super-enhancer activation. Super-enhancers of these genes were activated prior to induction of the transcripts and myeloid differentiation. Depletion of GFI1 attenuated myeloid differentiation by NCD38. Finally, a single administration of NCD38 causes the in vivo eradication of primary MDS-related leukemia cells with a complex karyotype. Together, NCD38 derepresses super-enhancers of hematopoietic regulators that are silenced abnormally by LSD1, attenuates leukemogenic programs and consequently exerts anti-leukemic effect against MDS-related leukemia with adverse outcome.

Developing a Practical Method for Validation of Computerized Systems Integrated With Smart and/or Wearable Devices for Regulatory Compliance of Clinical Trials

BACKGROUND

The use of smart and/or wearable devices for collection of electronic data in clinical trials has recently become a strong tool with which to collect patients' data in a timely manner. Electronic collection of patient data will necessitate comprehensive data analysis involving huge-scale datasets in the future. However, it is still unclear how to validate and qualify computerized systems used to collect and/or manage electronic clinical data when smart and/or wearable devices are involved.

METHODS

We (a special interest group of Good Automated Manufacturing Practice Japan Forum [GAMP Japan]) investigated and designed a data-flow model for a clinical data management system involving smart and/or wearable devices, and suggested an approach for the validation of such a computerized system. The appropriateness of applying GAMP5 to the validation of a clinical data management system involving smart and/or wearable devices was also reviewed.

RESULTS

A regulated company should have policies and standard procedures for validating computerized systems in clinical systems. When a sponsor engages a contract research organization (CRO) for clinical data management, the sponsor should assess the CRO to confirm their capabilities. The sponsor also needs to check whether the CRO assesses device manufacturers as sub-suppliers. When the CRO intends to conduct sub-supplier assessment with a device manufacturer, a risk-based approach can be taken.

CONCLUSIONS

We believe our method of system validation will be applicable to and will facilitate various clinical trials that involve smart and/or wearable devices.